We investigate the population and several properties of radio pulsars whose emission does not null(non-nulling)through simulation of a large pulsar sample.Emission from a pulsar is identified as non-nulling if(i)the e...We investigate the population and several properties of radio pulsars whose emission does not null(non-nulling)through simulation of a large pulsar sample.Emission from a pulsar is identified as non-nulling if(i)the emission does not cease across the whole pulse profile,and(ii)the emission is detectable.For(i),we adopt a model for switching in the plasma charge density,and emission persists if the charge density is non-zero.For(ii),we assume that detectable emission originates from source points where it is emitted tangentially to the magnetic field-line and parallel to the line-of-sight.We find that pulsars exhibiting non-nulling emission possess obliquity angles with an average of 42°.5,and almost half the samples maintain a duty cycle between 0.05 and 0.2.Furthermore,the pulsar population is not fixed but dependent on the obliquity angle,with the population peaking at 20°.In addition,three evolutionary phases are identified in the pulsar population as the obliquity angle evolves,with the majority of samples having an obliquity angle between 20°and 65°.Our results also suggest that emission from a pulsar may evolve between nulling and non-nulling during its lifetime.展开更多
Polycystic ovary syndrome(PCOS) is a common endocrine disorder that affects up to 6.8% of reproductive age women.Experimental research and clinical observations suggest that PCOS may originate in the very early stages...Polycystic ovary syndrome(PCOS) is a common endocrine disorder that affects up to 6.8% of reproductive age women.Experimental research and clinical observations suggest that PCOS may originate in the very early stages of development,possibly even during intrauterine life.This suggests that PCOS is either genetically-transmittedor is due to epigenetic alterations that develop in the intrauterine microenvironment.Although familial cases support the role of genetic factors,no specific genetic pattern has been defined in PCOS.Several candidate genes have been implicated in its pathogenesis,but none can specifically be implicated in PCOS development.Hypotheses based on the impact of the intrauterine environment on PCOS development can be grouped into two categories.The first is the "thrifty" phenotype hypothesis,which states that intrauterine nutritional restriction in fetuses causes decreased insulin secretion and,as a compensatory mechanism,insulin resistance.Additionally,an impaired nutritional environment can affect the methylation of some specific genes,which can also trigger PCOS.The second hypothesis postulates that fetal exposure to excess androgen can induce changes in differentiating tissues,causing the PCOS phenotype to develop in adult life.This review aimed to examine the role of fetal programming in development of PCOS.展开更多
The manuscript titled "Vacuoles of Candida yeast behave as a specialized niche for Helicobacter pylori(H.pylori)" not only has not been prepared in a scientific manner but the methodology used was not adequa...The manuscript titled "Vacuoles of Candida yeast behave as a specialized niche for Helicobacter pylori(H.pylori)" not only has not been prepared in a scientific manner but the methodology used was not adequate, and therefore the conclusion reached was not correct. First of all, "yeast" is a broad terminology covering a great number of genera and species of unicellular micro-organisms. The authors should have defined the organism with its binary scientific name. This measure would allow experiment reproduction by the scientific community. Moreover, the criteria established by Robert Koch to identify a specific microorganism or pathogen was not adopted in the methodology used. Regarding the methodology applied, use of the chicken eggyolk(Ig Y) antibody and PCR of the apparently tainted yeast population to prove H. pylori existence in the yeast vacuoles might be main factors for their wrong conclusions. Bacterial tropism toward yeast extract is a known phenomenon, and yeast extract is one of the main ingredients in culture media. Their internalization through phagocytosis or similar pathways does not seem possible or practical because of the thick and cellulosic yeast wall. While the small size of yeast cells does not support their ability in harboring several H. pylori, other observations such as inefficiency of antifungal therapy as anti-Helicobacter therapy strongly reject the conclusion reached by the above-mentioned article.展开更多
The aim of this study was to evaluate the relationship between lower urinary tract symptoms (LUTSs), erectile dysfunction (ED) and symptomatic late-onset hypogonadism (SLOH) in ageing men in the Aegean region of...The aim of this study was to evaluate the relationship between lower urinary tract symptoms (LUTSs), erectile dysfunction (ED) and symptomatic late-onset hypogonadism (SLOH) in ageing men in the Aegean region of Turkey. Five hundred consecutive patients 〉40 years old who had been in a steady sexual relationship for the past 6 months and were admitted to one of six urology clinics were included in the study. Serum prostate-specific antigen and testosterone levels and urinary flow rates were measured. All patients filled out the International Prostate Symptom Score and Quality of Life (IPSS-QoL), International Index of Erectile Function (IIEF) and Aging Males' Symptoms (AMS) scale forms. Of the patients, 23.9% had mild LUTSs, 53.3% had moderate LUTSs and 22.8% had severe LUTSs. The total testosterone level did not differ between groups. Additionally, 69.6% had ED. The presence of impotence increased with increasing LUTS severity. Symptomatic late-onset hypogonadism (AMS 〉27) was observed in 71.2% of the patients. The prevalence of severe hypogonadism symptoms increased with the IPSS scores. A correlation analysis revealed that all three questionnaire scores were significantly correlated. In conclusion, LUTS severity is an age-independent risk factor for ED and SLOH. LUTS severity and SLOH symptoms appear to have a strong link that requires etiological and biological clarification in future studies.展开更多
High precision and long-lasting Kepler data enabled us to estimate stellar properties with asteroseismology as an accurate tool. We performed asteroseismic analysis on six solar-like stars observed by the Kepler miss...High precision and long-lasting Kepler data enabled us to estimate stellar properties with asteroseismology as an accurate tool. We performed asteroseismic analysis on six solar-like stars observed by the Kepler mission: KIC 6064910, KIC 6766513, KIC 7107778, KIC 10079226, KIC 10147635 and KIC 12069127. The extraction of seismic information includes two parts. First, we obtained two global asteroseismic parameters, mean large separation ?_ν and frequency of maximum power ν_(max),with autocorrelation function and collapsed autocorrelation function. Second, we extracted individual oscillation modes ν_(nl) with low-l degree using a least-squares fit. Stellar grid models were built with Yale Rotating Stellar Evolution Code(YREC) to analyze stellar properties. They covered the range of M = 0.8 ~ 1.8 M_⊙with a step of 0.02 M_⊙ and [Fe/H] =-0.3 ~ 0.4 dex with a step of 0.1 dex.We used a Bayesian approach to estimate stellar fundamental parameters of the six stars, under the constraints of asteroseismic parameters(?_ν, ν_(max)) and non-asteroseismic parameters(Teff, [Fe/H]). We discover that the six targets include five sub-giant stars with 1.2 ~1.5 M_⊙ and one main-sequence star with 1.08 M_⊙, and with ages in the range of 3 ~5 Gyr.展开更多
It is a fact that performing endoscopy using conventional methods requires substantial time and development of alternative diagnostic modalities. Replacement of rigid endoscopes with flexible and digital devices in ti...It is a fact that performing endoscopy using conventional methods requires substantial time and development of alternative diagnostic modalities. Replacement of rigid endoscopes with flexible and digital devices in time, faster performance of the procedures and reduced time for them to turn back to work brought about the expectancy. It was possible that easier and more reliable methods could exist. Idea of capsule endoscopy was born following examination of the gastrointestinal tract with an endoscope with shape of a capsule. Although idea of capsule endoscopy was suggested long years ago, it fell behind the advances in conventional step of the endoscopy, especially developmental speed of the flexible devices. Furthermore, three-dimensional (3D) organ views can be processed digitally by means of sophisticated software in the fields of computerized tomography and magnetic resonance imaging. Thus, virtual cystoscopy of high resolution and specificity is possible by means of both methods. Wireless capsule endoscopy is still in the experimental stage. “Steerable independent intracorporeal endoscope” with feature of consecutive instillation in addition to its diagnostic utility is not a dream.展开更多
It is widely accepted that solar flares involve release of magnetic energy stored in the solar corona above an active region, but existing models do not include the explicitly time-dependent electrodynamics needed to ...It is widely accepted that solar flares involve release of magnetic energy stored in the solar corona above an active region, but existing models do not include the explicitly time-dependent electrodynamics needed to describe such energy release. A flare paradigm is discussed that includes the electromotive force (EMF) as the driver of the flare, and the flare-associated current that links different regions where magnetic reconnection, electron acceleration, the acceleration of mass motions and current closure occur. The EMF becomes localized across regions where energy conversion occurs, and is involved in energy propagation between these regions.展开更多
St.John's Wort(SJW) is an old herb which has long been consumed widely for its anti-inflammatory,antiviral,and anti-depressive properties.Here we present a detailed clinical evaluation of three cases(two colon and...St.John's Wort(SJW) is an old herb which has long been consumed widely for its anti-inflammatory,antiviral,and anti-depressive properties.Here we present a detailed clinical evaluation of three cases(two colon and one duodenal adenocarcinoma) with remarkable and intensive lymphoplasmocytic host reaction,at the basal part of tumor,intensive fibrosis,giant cells,plasma cell increase in lymph nodes and few giant cells in germinal centers in resection specimens.The observation of similar host reaction in those tumors having otherwise usual appearance was interesting.None of the cases received neoadjuvant chemoradiotherapy or additional treatment before surgery but only SJW.These cases are presented to increase the awareness about such cases.Further research is needed to reveal the possible effect of SJW,which has long been consumed for different treatment purposes,on human tumors.展开更多
Dear Editor, Among the sex cord tumours, Sertoli cell tumours constitute 1% of all testicular tumours. The association between Sertoli cell tumours and azoospermia is not well defined, and the patient described in th...Dear Editor, Among the sex cord tumours, Sertoli cell tumours constitute 1% of all testicular tumours. The association between Sertoli cell tumours and azoospermia is not well defined, and the patient described in this letter is the second case reported in the literature.展开更多
We investigate relations in the emission properties as revealed by drifting subpulses detected at different observing frequencies based on the method that incorporates the rotating carousels in pulsar magnetospheres o...We investigate relations in the emission properties as revealed by drifting subpulses detected at different observing frequencies based on the method that incorporates the rotating carousels in pulsar magnetospheres of multiple emission states.An emission state is associated with particular emission properties as determined by the drifting subpulses at a particular frequency,and different emission states obtained at different frequencies reveal the variation of emission properties across the emission region.The method allows the determination of the essential radio emission properties such as the relative emission height,subpulse number,charge density and the plasma flow relative to corotation in an emission region for a particular frequency.We apply the method to seven pulsars that exhibit subpulse drifting along single drift-band at 326 MHz and 1429 MHz.Our results show that drifting subpulses observed at different frequencies correspond to particular emission states suggesting that the pulsar emission properties are frequency dependent.We show that emission follows the frequency-to-radius mapping for pulsars with obliquity angle?30°regardless of the sign and magnitude of the drift-rate.For pulsars with long rotation periods in our sample,the circulation time for the plasma to revolve once around the magnetosphere relative to corotation increases as the rotation period increases at both frequencies,but exhibits irregularity for pulsars with short rotation periods.Our results suggest that evolution of the obliquity angles in subpulse drifting pulsars is from large to small,and the emission region tends to be’thicker’in younger pulsars.展开更多
Object?ves: As we known that the internal thoracic artery (ITA) has an excellent patency rate in coronary artery bypass grafting (CABG). However, early graft failure due to occlusion and spasm is still the major probl...Object?ves: As we known that the internal thoracic artery (ITA) has an excellent patency rate in coronary artery bypass grafting (CABG). However, early graft failure due to occlusion and spasm is still the major problem after coronary artery bypass surgery. We examined histopathologic findings of the clipped internal thoracic artery (ITA) in patients undergoing CABG using transmission electron microscope (TEM). Methods: To investigate the histopathololojic ITA examination, 60 patients were randomly selected. The ITA was harvested in a standart fashion with the use of low voltage electrocotery and its distal end was cut prior to bifurcation and clipped. Just before the ITA anastomosis 1 mm lenght of ITA ring was cut and saved in 2.5% Glutaraldehide solution for fixation and examination of transmission electron microscope (TEM). One blinded anatomopatholog examined all specimens and described the endothelial integrity according to the score system proposed by Fischlein et al. Results: In ten cases (17.5%) different degree of histopathologic findings (endothelial cells, intercellular and intracellular organels and adventitia) were recorded The most important histopatholojic findings of ITA were as follows: endothelial vacuolisation, intimal thickening and/or intimal seperation, suben-dothelial edema, swallowing of cytoplasma and mito-condria. Conclusion: Our results showed that the endothelial pathology is high when the ITA clipped. Unfortunataly, because our study did not include the non-clipped ITA we have not concluded the comparison or statistical results. In our opinion, for absolute definition of the effects of the clipping the ITA it should be planned the comparative results between the clipped and non-clipped ITA histologic examinations.展开更多
Modification of a surface of strontium titanate single crystals as pure as doped with Mn (Ni) or Nd (Sm) ions after plasma treatment was studied by combination of scanning electron microscopy and atomic force microsco...Modification of a surface of strontium titanate single crystals as pure as doped with Mn (Ni) or Nd (Sm) ions after plasma treatment was studied by combination of scanning electron microscopy and atomic force microscopy techniques. Valence shift method for characteristic X ray lines was used for study of stoichiometry violation and oxidation state of ions on the crystals surface after plasma treatment. One-and two-level ordered systems of unit crystallites sized of about 10-7 – 10-10 m were discovered on samples surface after plasma treatment with energy density of about 5 - 20 (40) J.cm-2. Oxidation state of Ti ions and stoichiometry of the surface changed essentially on background of high stability of strontium ions valence.展开更多
Purpose: To compare perioperative and postoperative outcomes of the first and following 50 cases of transcanalicular laser dacryocystorhinostomy performed by a surgeon team. Methods: Results of 124 eyes of 115 patient...Purpose: To compare perioperative and postoperative outcomes of the first and following 50 cases of transcanalicular laser dacryocystorhinostomy performed by a surgeon team. Methods: Results of 124 eyes of 115 patients who had a diagnosis of distal obstruction of the lacrimal drainage system and underwent transcanalicular laser dacryocystorhinostomy procedures were retrospectively detected. Initial 50 eyes were considered as group 1;74 following eyes were accepted as group 2. Groups were compared regarding age, gender, total surgical time, time for creation of osteotomy, pain score, bleeding score, anatomic and functional success rates. Results: The average total surgical time was 43.2 ± 6.0 minutes (range: 31 to 65 minutes) in group 1, and 30.0 ± 6.4 minutes (range: 21 to 57 minutes) in group 2 (p < 0.001). Laser osteotomy creation required 25.0 ± 4.2 minutes (range: 14 to 34 minutes) in group 1, and 14.6 ± 3.6 months (range: 9 to 28 minutes) (p < 0.001). Intraoperative pain and bleeding scores were significantly better in group 2 (p < 0.001 and p < 0.001 respectively). Success rate was 54.0% in group 1, and 85.1% in group 2 (p < 0.001). Conclusion: The results of current study clearly showed that increased experience of a surgeon results with improvement of better surgical outcomes. Initial studies about a novel technique should make clear if the study cases are the beginning cases of the authors.展开更多
The change of sound speed has been found at the base of the convection during the solar cycles,which can be used to constrain the solar internal magnetic field.We aim to check whether the magnetic field generated by t...The change of sound speed has been found at the base of the convection during the solar cycles,which can be used to constrain the solar internal magnetic field.We aim to check whether the magnetic field generated by the solar dynamo can lead to the cyclic variation of the sound speed detected through helioseismology.The basic configuration of magnetic field in the solar interior was obtained by using a Babcock-Leighton(BL)type flux transport dynamo.We reconstructed one-dimensional solar models by assimilating magnetic field generated by an established dynamo and examined their influences on the structural variables.The results show that magnetic field generated by the dynamo is able to cause noticeable change of the sound speed profile at the base of the convective zone during a solar cycle.Detailed features of this theoretical prediction are also similar to those of the helioseismic results in solar cycle 23 by adjusting the free parameters of the dynamo model.展开更多
Percutaneous nephrolithotomy (PCNL) is very popular and an efficient method as a gold standard in management of renal calculi. It is the first-choice method in management of renal calculi larger than 2 cm. Our patient...Percutaneous nephrolithotomy (PCNL) is very popular and an efficient method as a gold standard in management of renal calculi. It is the first-choice method in management of renal calculi larger than 2 cm. Our patient underwent PCNL upon observing multiple renal calculi larger than 10 mm in a lower pole of the right kidney. Biopsy was performed during PNCL because morphology and endoscopic view of the calyx were irregular, calcific and pale white in color. The patient developed prolonged urinary leakage from the lumbar region and J-stent was inserted after the re-entry catheter had been removed following successful PCNL. Prolonged urinary leakage persisted although location of the J-stent was normal. Tuberculosis of the urinary tract should be the first option in the dif ferential diagnosis of fistula discharge following PCNL. In our patient, the biopsy taken at the time of PCNL revealed renal tuberculosis. Urinary tract tuberculosis must definitely be considered in the fistula tract persisted and not closed fol lowing PCNL as in the present case. Diagnosis of tuberculosis was made early in this case owing to tissue sampling during operation, and thus the treatment was begun early. So we consider this patient as a special case.展开更多
Isolated tricuspid valve infective endocarditis (TVIE) is a rare clinical condition. Thus, there is no common consensus for the treatment options for TVIE. Vege-tectomy and valvulectomy, valve repair, and valve replac...Isolated tricuspid valve infective endocarditis (TVIE) is a rare clinical condition. Thus, there is no common consensus for the treatment options for TVIE. Vege-tectomy and valvulectomy, valve repair, and valve replacement, which are controversial in regard to hemodynamic consequences in right-sided low-pressure system and long-term prognosis. We present 2 young intravenous drug users with TVIE and our surgical strategy.展开更多
Objective: The internal thoracic artery (ITA) is the conduit of choice for coronary artery bypass grafting (CABG). To avoid spasm of the ITA various topical vasodilators have been suggested either intraluminally or by...Objective: The internal thoracic artery (ITA) is the conduit of choice for coronary artery bypass grafting (CABG). To avoid spasm of the ITA various topical vasodilators have been suggested either intraluminally or by topical application. In order to describe the best vasodilating agent for preparation of the ITA, a randomized double-blind placebo controlled clinical work was performed in a group of CABG patients. Methods: Three hundred consecutive patients submitted for elective first time coronary artery bypass grafting were randomly subdivided into five groups. The first measurement was performed shortly after the internal thoracic artery was dissected from the chest wall and the second just prior to performing distal anastomosis to the left anterior descending coronary artery. During the time interval between the two measurements topical vasodilator has been injected into the endothoracic fascia of the ITA using the following drugs: papaverine 2 mg/ml, nitrogly-cerin 1 mg/ml, nitroprusside 0.5 mg/ml, mixed solution include sodium nitroprusside (1 mg/ml) and diltiazem (0.5 mg/ml) and normal saline 0.9%. Results: No statistically significant differences were found between the groups in respect to age, body surface area, cardiopulmonary bypass time, cross clamping time, and time interval between the two flow measurements. Mean arterial pressure at the time of the first and second internal thoracic artery flow measurements did not show statistically significant differences either within or between the groups. In all five groups, the free flow of the internal thoracic artery increased significantly with time. However, no statistically significant differences were shown between the five groups with respect to second flow. Conclusions: We suggest that preparation of the ITA by topical vasodilators injection into the endothoracic fascia does not result in a significantly superior free flow than placebo.展开更多
Background: The radial artery (RA) is being used as a second arterial conduit in coronary artery bypass grafting (CABG) patients. Vasospasm during the harvesting is the most common problem, yet. Our goal of this resea...Background: The radial artery (RA) is being used as a second arterial conduit in coronary artery bypass grafting (CABG) patients. Vasospasm during the harvesting is the most common problem, yet. Our goal of this research is to evaluate the effects of different vasodilators on RA blood flow. Material and Method: In our 250 CABG patients who were included into the study, patients were divided into five groups which have the same number of the patients. Before the harvesting of the RA, Allen test and modified Allen test were performed. In group 1, sodium nitroprusside (SNP) was administered via central line. In group 2, nitrogliceryne was applied as a vasodilator agent. In group 3, diltiazem as a calcium channel blocker was used. In group 4, dobutamine was used with a dose of 3micro./kg/min. In the remaining patients, as a control group (CG), normal saline solution was used with the same protocol. RA length and radial artery flow, mean arterial blood pressure, central venous pressure, and heart rate were measured before and 10 minutes after drug administration. Results: No significant differences were found between the groups in respect to age, body surface area, cardiopulmonary bypass time, aortic cross clamp time. A multivariate general linear model was created and revealed the drug (specifically SNP and nitroglycerin) as a predictor to increase flow in the radial artery (p = 0.001 and p = 0.002), respectively. SNP has significantly decreased mean arterial pressure when we compared to nitroglycerin (p 0.05). Conclusions: Our study showed that SNP and nitroglycerin are very effective agents to provide the increasing of RA blood flow. However, statistical comparisons exhibited that intravenous SNP was a very effective vasodilating agent for RA than nitroglycerin.展开更多
Background: Although the radial artery (RA) is mostly selected for the creating of arterio-venous fistula (AVF) in end-stage renal disease patients (ESRDP), it still represents a suitable site to simply assess systemi...Background: Although the radial artery (RA) is mostly selected for the creating of arterio-venous fistula (AVF) in end-stage renal disease patients (ESRDP), it still represents a suitable site to simply assess systemic calcification. Our goal of this study was to research the RA before the arteriovenous fistula creation in ESRDP and evaluate the risk factor determinants. Material and Methods: The RA has been determined to estimate vascular calcification in 67 ESRDPs on dialysis by doppler ultrasonography (USG). If there was any pathologic conditions, direct examination of the forehand soft tissue roentgenograms as a simply method was made. Preoperative spectral Doppler sonography measured radial artery peak systolic velocity during tight fist clenching for 3 minutes and after fist relaxation. Vessel diameters and peak systolic velocity were assessed for predictive value based on subsequent fistula adequacy. RA calcification was scored from Grade 0 which was defined as no calcification to Grade 4 which was described as severe calcification from proximal to distal end of RA. Results: Doppler USG has shown that the major or minor RA calcification was detected in 11 patients (16.5%). In these patients, direct roentgenogram also demonstrated RA calcific disease. Total and LDL cholesterol levels, gender and smoking status have no influence on calcification scores. When the dialysis periods are concerned, there was no correlation with the RA calcification. Serum calcium and phosphate levels, rather than calcium-phosphate products, and age were correlated with high calcification scores. The highest prevalence of RA calcification was also found in diabetic group. Conclusion: Our data indicate that RA calcification is highly prevalent among ESRDP, with the highest prevalence among diabetics. The RA was used as an A-V fistual creation in ESRDPs, which may be risky since the calcification percentage is higher. Therefore, a simple roentgenographic survey may help to identify patients with severe calcified RA. Because our roengenographyc results were correlated with doppler USG, it can be used to determine RA calcific disease before the arteriovenous fistula creation.展开更多
Pregnancy in women with mechanical prosthetic heart valves is associated with an increased risk of maternal and fetal complications. Managing of the anticoagulation of these patients is very important for life saving ...Pregnancy in women with mechanical prosthetic heart valves is associated with an increased risk of maternal and fetal complications. Managing of the anticoagulation of these patients is very important for life saving of mother and fetus. Unfortunately, throm- boembolic complications in some pregnant women with mechanical mitral valve can be seen. Herein, we present urgent mechanical mitral valve replacement in a 27 year old pregnant woman due to stuck mecha- nical valve.展开更多
基金supported by the National SKA Program of China No.2020SKA0120200the National Key Program for Science and Technology Research and Development No.2022YFC2205201+2 种基金the National Natural Science Foundation of China(NSFC,grant Nos.12288102,12041303,and 12041304)the Major Science and Technology Program of Xinjiang Uygur Autonomous Region No.2022A03013-2the open program of the Key Laboratory of Xinjiang Uygur Autonomous Region No.2020D04049。
文摘We investigate the population and several properties of radio pulsars whose emission does not null(non-nulling)through simulation of a large pulsar sample.Emission from a pulsar is identified as non-nulling if(i)the emission does not cease across the whole pulse profile,and(ii)the emission is detectable.For(i),we adopt a model for switching in the plasma charge density,and emission persists if the charge density is non-zero.For(ii),we assume that detectable emission originates from source points where it is emitted tangentially to the magnetic field-line and parallel to the line-of-sight.We find that pulsars exhibiting non-nulling emission possess obliquity angles with an average of 42°.5,and almost half the samples maintain a duty cycle between 0.05 and 0.2.Furthermore,the pulsar population is not fixed but dependent on the obliquity angle,with the population peaking at 20°.In addition,three evolutionary phases are identified in the pulsar population as the obliquity angle evolves,with the majority of samples having an obliquity angle between 20°and 65°.Our results also suggest that emission from a pulsar may evolve between nulling and non-nulling during its lifetime.
文摘Polycystic ovary syndrome(PCOS) is a common endocrine disorder that affects up to 6.8% of reproductive age women.Experimental research and clinical observations suggest that PCOS may originate in the very early stages of development,possibly even during intrauterine life.This suggests that PCOS is either genetically-transmittedor is due to epigenetic alterations that develop in the intrauterine microenvironment.Although familial cases support the role of genetic factors,no specific genetic pattern has been defined in PCOS.Several candidate genes have been implicated in its pathogenesis,but none can specifically be implicated in PCOS development.Hypotheses based on the impact of the intrauterine environment on PCOS development can be grouped into two categories.The first is the "thrifty" phenotype hypothesis,which states that intrauterine nutritional restriction in fetuses causes decreased insulin secretion and,as a compensatory mechanism,insulin resistance.Additionally,an impaired nutritional environment can affect the methylation of some specific genes,which can also trigger PCOS.The second hypothesis postulates that fetal exposure to excess androgen can induce changes in differentiating tissues,causing the PCOS phenotype to develop in adult life.This review aimed to examine the role of fetal programming in development of PCOS.
文摘The manuscript titled "Vacuoles of Candida yeast behave as a specialized niche for Helicobacter pylori(H.pylori)" not only has not been prepared in a scientific manner but the methodology used was not adequate, and therefore the conclusion reached was not correct. First of all, "yeast" is a broad terminology covering a great number of genera and species of unicellular micro-organisms. The authors should have defined the organism with its binary scientific name. This measure would allow experiment reproduction by the scientific community. Moreover, the criteria established by Robert Koch to identify a specific microorganism or pathogen was not adopted in the methodology used. Regarding the methodology applied, use of the chicken eggyolk(Ig Y) antibody and PCR of the apparently tainted yeast population to prove H. pylori existence in the yeast vacuoles might be main factors for their wrong conclusions. Bacterial tropism toward yeast extract is a known phenomenon, and yeast extract is one of the main ingredients in culture media. Their internalization through phagocytosis or similar pathways does not seem possible or practical because of the thick and cellulosic yeast wall. While the small size of yeast cells does not support their ability in harboring several H. pylori, other observations such as inefficiency of antifungal therapy as anti-Helicobacter therapy strongly reject the conclusion reached by the above-mentioned article.
文摘The aim of this study was to evaluate the relationship between lower urinary tract symptoms (LUTSs), erectile dysfunction (ED) and symptomatic late-onset hypogonadism (SLOH) in ageing men in the Aegean region of Turkey. Five hundred consecutive patients 〉40 years old who had been in a steady sexual relationship for the past 6 months and were admitted to one of six urology clinics were included in the study. Serum prostate-specific antigen and testosterone levels and urinary flow rates were measured. All patients filled out the International Prostate Symptom Score and Quality of Life (IPSS-QoL), International Index of Erectile Function (IIEF) and Aging Males' Symptoms (AMS) scale forms. Of the patients, 23.9% had mild LUTSs, 53.3% had moderate LUTSs and 22.8% had severe LUTSs. The total testosterone level did not differ between groups. Additionally, 69.6% had ED. The presence of impotence increased with increasing LUTS severity. Symptomatic late-onset hypogonadism (AMS 〉27) was observed in 71.2% of the patients. The prevalence of severe hypogonadism symptoms increased with the IPSS scores. A correlation analysis revealed that all three questionnaire scores were significantly correlated. In conclusion, LUTS severity is an age-independent risk factor for ED and SLOH. LUTS severity and SLOH symptoms appear to have a strong link that requires etiological and biological clarification in future studies.
基金provided by National College Students Innovation Training Programsupported by the National Natural Science Foundation of China (NSFC, Grant Nos. 11273007 and 10933002)+1 种基金the Joint Research Fund in Astronomy (U1631236) under cooperative agreement between the NSFC and Chinese Academy of Sciences (CAS)the Fundamental Research Funds for the Central Universities
文摘High precision and long-lasting Kepler data enabled us to estimate stellar properties with asteroseismology as an accurate tool. We performed asteroseismic analysis on six solar-like stars observed by the Kepler mission: KIC 6064910, KIC 6766513, KIC 7107778, KIC 10079226, KIC 10147635 and KIC 12069127. The extraction of seismic information includes two parts. First, we obtained two global asteroseismic parameters, mean large separation ?_ν and frequency of maximum power ν_(max),with autocorrelation function and collapsed autocorrelation function. Second, we extracted individual oscillation modes ν_(nl) with low-l degree using a least-squares fit. Stellar grid models were built with Yale Rotating Stellar Evolution Code(YREC) to analyze stellar properties. They covered the range of M = 0.8 ~ 1.8 M_⊙with a step of 0.02 M_⊙ and [Fe/H] =-0.3 ~ 0.4 dex with a step of 0.1 dex.We used a Bayesian approach to estimate stellar fundamental parameters of the six stars, under the constraints of asteroseismic parameters(?_ν, ν_(max)) and non-asteroseismic parameters(Teff, [Fe/H]). We discover that the six targets include five sub-giant stars with 1.2 ~1.5 M_⊙ and one main-sequence star with 1.08 M_⊙, and with ages in the range of 3 ~5 Gyr.
文摘It is a fact that performing endoscopy using conventional methods requires substantial time and development of alternative diagnostic modalities. Replacement of rigid endoscopes with flexible and digital devices in time, faster performance of the procedures and reduced time for them to turn back to work brought about the expectancy. It was possible that easier and more reliable methods could exist. Idea of capsule endoscopy was born following examination of the gastrointestinal tract with an endoscope with shape of a capsule. Although idea of capsule endoscopy was suggested long years ago, it fell behind the advances in conventional step of the endoscopy, especially developmental speed of the flexible devices. Furthermore, three-dimensional (3D) organ views can be processed digitally by means of sophisticated software in the fields of computerized tomography and magnetic resonance imaging. Thus, virtual cystoscopy of high resolution and specificity is possible by means of both methods. Wireless capsule endoscopy is still in the experimental stage. “Steerable independent intracorporeal endoscope” with feature of consecutive instillation in addition to its diagnostic utility is not a dream.
文摘It is widely accepted that solar flares involve release of magnetic energy stored in the solar corona above an active region, but existing models do not include the explicitly time-dependent electrodynamics needed to describe such energy release. A flare paradigm is discussed that includes the electromotive force (EMF) as the driver of the flare, and the flare-associated current that links different regions where magnetic reconnection, electron acceleration, the acceleration of mass motions and current closure occur. The EMF becomes localized across regions where energy conversion occurs, and is involved in energy propagation between these regions.
文摘St.John's Wort(SJW) is an old herb which has long been consumed widely for its anti-inflammatory,antiviral,and anti-depressive properties.Here we present a detailed clinical evaluation of three cases(two colon and one duodenal adenocarcinoma) with remarkable and intensive lymphoplasmocytic host reaction,at the basal part of tumor,intensive fibrosis,giant cells,plasma cell increase in lymph nodes and few giant cells in germinal centers in resection specimens.The observation of similar host reaction in those tumors having otherwise usual appearance was interesting.None of the cases received neoadjuvant chemoradiotherapy or additional treatment before surgery but only SJW.These cases are presented to increase the awareness about such cases.Further research is needed to reveal the possible effect of SJW,which has long been consumed for different treatment purposes,on human tumors.
文摘Dear Editor, Among the sex cord tumours, Sertoli cell tumours constitute 1% of all testicular tumours. The association between Sertoli cell tumours and azoospermia is not well defined, and the patient described in this letter is the second case reported in the literature.
基金supported by the National Natural Science Foundation of China(grant Nos.U1838109,11873080 and 12041301)the open program of the Key Laboratory of Xinjiang Uygur Autonomous Region under grant No.2020D04049+2 种基金the 2018 Project of Xinjiang Uygur Autonomous Region of China for Flexibly Fetching in Upscale Talentspartly supported by Xiaofeng Yang’s Xinjiang Tianchi Bairen projectCAS Pioneer Hundred Talents Program。
文摘We investigate relations in the emission properties as revealed by drifting subpulses detected at different observing frequencies based on the method that incorporates the rotating carousels in pulsar magnetospheres of multiple emission states.An emission state is associated with particular emission properties as determined by the drifting subpulses at a particular frequency,and different emission states obtained at different frequencies reveal the variation of emission properties across the emission region.The method allows the determination of the essential radio emission properties such as the relative emission height,subpulse number,charge density and the plasma flow relative to corotation in an emission region for a particular frequency.We apply the method to seven pulsars that exhibit subpulse drifting along single drift-band at 326 MHz and 1429 MHz.Our results show that drifting subpulses observed at different frequencies correspond to particular emission states suggesting that the pulsar emission properties are frequency dependent.We show that emission follows the frequency-to-radius mapping for pulsars with obliquity angle?30°regardless of the sign and magnitude of the drift-rate.For pulsars with long rotation periods in our sample,the circulation time for the plasma to revolve once around the magnetosphere relative to corotation increases as the rotation period increases at both frequencies,but exhibits irregularity for pulsars with short rotation periods.Our results suggest that evolution of the obliquity angles in subpulse drifting pulsars is from large to small,and the emission region tends to be’thicker’in younger pulsars.
文摘Object?ves: As we known that the internal thoracic artery (ITA) has an excellent patency rate in coronary artery bypass grafting (CABG). However, early graft failure due to occlusion and spasm is still the major problem after coronary artery bypass surgery. We examined histopathologic findings of the clipped internal thoracic artery (ITA) in patients undergoing CABG using transmission electron microscope (TEM). Methods: To investigate the histopathololojic ITA examination, 60 patients were randomly selected. The ITA was harvested in a standart fashion with the use of low voltage electrocotery and its distal end was cut prior to bifurcation and clipped. Just before the ITA anastomosis 1 mm lenght of ITA ring was cut and saved in 2.5% Glutaraldehide solution for fixation and examination of transmission electron microscope (TEM). One blinded anatomopatholog examined all specimens and described the endothelial integrity according to the score system proposed by Fischlein et al. Results: In ten cases (17.5%) different degree of histopathologic findings (endothelial cells, intercellular and intracellular organels and adventitia) were recorded The most important histopatholojic findings of ITA were as follows: endothelial vacuolisation, intimal thickening and/or intimal seperation, suben-dothelial edema, swallowing of cytoplasma and mito-condria. Conclusion: Our results showed that the endothelial pathology is high when the ITA clipped. Unfortunataly, because our study did not include the non-clipped ITA we have not concluded the comparison or statistical results. In our opinion, for absolute definition of the effects of the clipping the ITA it should be planned the comparative results between the clipped and non-clipped ITA histologic examinations.
文摘Modification of a surface of strontium titanate single crystals as pure as doped with Mn (Ni) or Nd (Sm) ions after plasma treatment was studied by combination of scanning electron microscopy and atomic force microscopy techniques. Valence shift method for characteristic X ray lines was used for study of stoichiometry violation and oxidation state of ions on the crystals surface after plasma treatment. One-and two-level ordered systems of unit crystallites sized of about 10-7 – 10-10 m were discovered on samples surface after plasma treatment with energy density of about 5 - 20 (40) J.cm-2. Oxidation state of Ti ions and stoichiometry of the surface changed essentially on background of high stability of strontium ions valence.
文摘Purpose: To compare perioperative and postoperative outcomes of the first and following 50 cases of transcanalicular laser dacryocystorhinostomy performed by a surgeon team. Methods: Results of 124 eyes of 115 patients who had a diagnosis of distal obstruction of the lacrimal drainage system and underwent transcanalicular laser dacryocystorhinostomy procedures were retrospectively detected. Initial 50 eyes were considered as group 1;74 following eyes were accepted as group 2. Groups were compared regarding age, gender, total surgical time, time for creation of osteotomy, pain score, bleeding score, anatomic and functional success rates. Results: The average total surgical time was 43.2 ± 6.0 minutes (range: 31 to 65 minutes) in group 1, and 30.0 ± 6.4 minutes (range: 21 to 57 minutes) in group 2 (p < 0.001). Laser osteotomy creation required 25.0 ± 4.2 minutes (range: 14 to 34 minutes) in group 1, and 14.6 ± 3.6 months (range: 9 to 28 minutes) (p < 0.001). Intraoperative pain and bleeding scores were significantly better in group 2 (p < 0.001 and p < 0.001 respectively). Success rate was 54.0% in group 1, and 85.1% in group 2 (p < 0.001). Conclusion: The results of current study clearly showed that increased experience of a surgeon results with improvement of better surgical outcomes. Initial studies about a novel technique should make clear if the study cases are the beginning cases of the authors.
基金supported by the Joint Research Fund in Astronomy(Grant Nos.U1631236,U2031203)under cooperative agreement between the National Natural Science Foundation of China(NSFC)and Chinese Academy of Sciences(CAS)NSFC(Grant No.11522325)the European Research Council(ERC)under the European Union’s Horizon 2020 research and innovation programme(CartographY GA.804752)。
文摘The change of sound speed has been found at the base of the convection during the solar cycles,which can be used to constrain the solar internal magnetic field.We aim to check whether the magnetic field generated by the solar dynamo can lead to the cyclic variation of the sound speed detected through helioseismology.The basic configuration of magnetic field in the solar interior was obtained by using a Babcock-Leighton(BL)type flux transport dynamo.We reconstructed one-dimensional solar models by assimilating magnetic field generated by an established dynamo and examined their influences on the structural variables.The results show that magnetic field generated by the dynamo is able to cause noticeable change of the sound speed profile at the base of the convective zone during a solar cycle.Detailed features of this theoretical prediction are also similar to those of the helioseismic results in solar cycle 23 by adjusting the free parameters of the dynamo model.
文摘Percutaneous nephrolithotomy (PCNL) is very popular and an efficient method as a gold standard in management of renal calculi. It is the first-choice method in management of renal calculi larger than 2 cm. Our patient underwent PCNL upon observing multiple renal calculi larger than 10 mm in a lower pole of the right kidney. Biopsy was performed during PNCL because morphology and endoscopic view of the calyx were irregular, calcific and pale white in color. The patient developed prolonged urinary leakage from the lumbar region and J-stent was inserted after the re-entry catheter had been removed following successful PCNL. Prolonged urinary leakage persisted although location of the J-stent was normal. Tuberculosis of the urinary tract should be the first option in the dif ferential diagnosis of fistula discharge following PCNL. In our patient, the biopsy taken at the time of PCNL revealed renal tuberculosis. Urinary tract tuberculosis must definitely be considered in the fistula tract persisted and not closed fol lowing PCNL as in the present case. Diagnosis of tuberculosis was made early in this case owing to tissue sampling during operation, and thus the treatment was begun early. So we consider this patient as a special case.
文摘Isolated tricuspid valve infective endocarditis (TVIE) is a rare clinical condition. Thus, there is no common consensus for the treatment options for TVIE. Vege-tectomy and valvulectomy, valve repair, and valve replacement, which are controversial in regard to hemodynamic consequences in right-sided low-pressure system and long-term prognosis. We present 2 young intravenous drug users with TVIE and our surgical strategy.
文摘Objective: The internal thoracic artery (ITA) is the conduit of choice for coronary artery bypass grafting (CABG). To avoid spasm of the ITA various topical vasodilators have been suggested either intraluminally or by topical application. In order to describe the best vasodilating agent for preparation of the ITA, a randomized double-blind placebo controlled clinical work was performed in a group of CABG patients. Methods: Three hundred consecutive patients submitted for elective first time coronary artery bypass grafting were randomly subdivided into five groups. The first measurement was performed shortly after the internal thoracic artery was dissected from the chest wall and the second just prior to performing distal anastomosis to the left anterior descending coronary artery. During the time interval between the two measurements topical vasodilator has been injected into the endothoracic fascia of the ITA using the following drugs: papaverine 2 mg/ml, nitrogly-cerin 1 mg/ml, nitroprusside 0.5 mg/ml, mixed solution include sodium nitroprusside (1 mg/ml) and diltiazem (0.5 mg/ml) and normal saline 0.9%. Results: No statistically significant differences were found between the groups in respect to age, body surface area, cardiopulmonary bypass time, cross clamping time, and time interval between the two flow measurements. Mean arterial pressure at the time of the first and second internal thoracic artery flow measurements did not show statistically significant differences either within or between the groups. In all five groups, the free flow of the internal thoracic artery increased significantly with time. However, no statistically significant differences were shown between the five groups with respect to second flow. Conclusions: We suggest that preparation of the ITA by topical vasodilators injection into the endothoracic fascia does not result in a significantly superior free flow than placebo.
文摘Background: The radial artery (RA) is being used as a second arterial conduit in coronary artery bypass grafting (CABG) patients. Vasospasm during the harvesting is the most common problem, yet. Our goal of this research is to evaluate the effects of different vasodilators on RA blood flow. Material and Method: In our 250 CABG patients who were included into the study, patients were divided into five groups which have the same number of the patients. Before the harvesting of the RA, Allen test and modified Allen test were performed. In group 1, sodium nitroprusside (SNP) was administered via central line. In group 2, nitrogliceryne was applied as a vasodilator agent. In group 3, diltiazem as a calcium channel blocker was used. In group 4, dobutamine was used with a dose of 3micro./kg/min. In the remaining patients, as a control group (CG), normal saline solution was used with the same protocol. RA length and radial artery flow, mean arterial blood pressure, central venous pressure, and heart rate were measured before and 10 minutes after drug administration. Results: No significant differences were found between the groups in respect to age, body surface area, cardiopulmonary bypass time, aortic cross clamp time. A multivariate general linear model was created and revealed the drug (specifically SNP and nitroglycerin) as a predictor to increase flow in the radial artery (p = 0.001 and p = 0.002), respectively. SNP has significantly decreased mean arterial pressure when we compared to nitroglycerin (p 0.05). Conclusions: Our study showed that SNP and nitroglycerin are very effective agents to provide the increasing of RA blood flow. However, statistical comparisons exhibited that intravenous SNP was a very effective vasodilating agent for RA than nitroglycerin.
文摘Background: Although the radial artery (RA) is mostly selected for the creating of arterio-venous fistula (AVF) in end-stage renal disease patients (ESRDP), it still represents a suitable site to simply assess systemic calcification. Our goal of this study was to research the RA before the arteriovenous fistula creation in ESRDP and evaluate the risk factor determinants. Material and Methods: The RA has been determined to estimate vascular calcification in 67 ESRDPs on dialysis by doppler ultrasonography (USG). If there was any pathologic conditions, direct examination of the forehand soft tissue roentgenograms as a simply method was made. Preoperative spectral Doppler sonography measured radial artery peak systolic velocity during tight fist clenching for 3 minutes and after fist relaxation. Vessel diameters and peak systolic velocity were assessed for predictive value based on subsequent fistula adequacy. RA calcification was scored from Grade 0 which was defined as no calcification to Grade 4 which was described as severe calcification from proximal to distal end of RA. Results: Doppler USG has shown that the major or minor RA calcification was detected in 11 patients (16.5%). In these patients, direct roentgenogram also demonstrated RA calcific disease. Total and LDL cholesterol levels, gender and smoking status have no influence on calcification scores. When the dialysis periods are concerned, there was no correlation with the RA calcification. Serum calcium and phosphate levels, rather than calcium-phosphate products, and age were correlated with high calcification scores. The highest prevalence of RA calcification was also found in diabetic group. Conclusion: Our data indicate that RA calcification is highly prevalent among ESRDP, with the highest prevalence among diabetics. The RA was used as an A-V fistual creation in ESRDPs, which may be risky since the calcification percentage is higher. Therefore, a simple roentgenographic survey may help to identify patients with severe calcified RA. Because our roengenographyc results were correlated with doppler USG, it can be used to determine RA calcific disease before the arteriovenous fistula creation.
文摘Pregnancy in women with mechanical prosthetic heart valves is associated with an increased risk of maternal and fetal complications. Managing of the anticoagulation of these patients is very important for life saving of mother and fetus. Unfortunately, throm- boembolic complications in some pregnant women with mechanical mitral valve can be seen. Herein, we present urgent mechanical mitral valve replacement in a 27 year old pregnant woman due to stuck mecha- nical valve.