BACKGROUND Colorectal cancer(CRC)is the third most common cancer and a significant cause of cancer-related mortality globally.Resistance to chemotherapy,especially during CRC treatment,leads to reduced effectiveness o...BACKGROUND Colorectal cancer(CRC)is the third most common cancer and a significant cause of cancer-related mortality globally.Resistance to chemotherapy,especially during CRC treatment,leads to reduced effectiveness of drugs and poor patient outcomes.Long noncoding RNAs(lncRNAs)have been implicated in various pathophysiological processes of tumor cells,including chemotherapy resistance,yet the roles of many lncRNAs in CRC remain unclear.AIM To identify and analyze the lncRNAs involved in oxaliplatin resistance in CRC and to understand the underlying molecular mechanisms influencing this resistance.METHODS Gene Expression Omnibus datasets GSE42387 and GSE30011 were reanalyzed to identify lncRNAs and mRNAs associated with oxaliplatin resistance.Various bioinformatics tools were employed to elucidate molecular mechanisms.The expression levels of lncRNAs and mRNAs were assessed via quantitative reverse transcription-polymerase chain reaction.Functional assays,including MTT,wound healing,and Transwell,were conducted to investigate the functional implications of lncRNA alterations.Interactions between lncRNAs and trans-cription factors were examined using RIP and luciferase reporter assays,while Western blotting was used to confirm downstream pathways.Additionally,a xenograft mouse model was utilized to study the in vivo effects of lncRNAs on chemotherapy resistance.RESULTS LncRNA prion protein testis specific(PRNT)was found to be upregulated in oxaliplatin-resistant CRC cell lines and negatively correlated with homeodomain interacting protein kinase 2(HIPK2)expression.PRNT was demonstrated to sponge transcription factor zinc finger protein 184(ZNF184),which in turn could regulate HIPK2 expression.Altered expression of PRNT influenced CRC cell sensitivity to oxaliplatin,with overexpression leading to decreased sensitivity and decreased expression reducing resistance.Both RIP and luciferase reporter assays indicated that ZNF184 and HIPK2 are targets of PRNT.The PRNT/ZNF184/HIPK2 axis was implicated in promoting CRC progression and oxaliplatin resistance both in vitro and in vivo.CONCLUSION The study concludes that PRNT is upregulated in oxaliplatin-resistant CRC cells and modulates the expression of HIPK2 by sponging ZNF184.This regulatory mechanism enhances CRC progression and resistance to oxaliplatin,positioning PRNT as a promising therapeutic target for CRC patients undergoing oxaliplatin-based chemotherapy.展开更多
Objective:To observe the effects of moxibustion at different temperatures(38℃,46℃)on blood lipids,endothelial morphology of the thoracic aorta,serum endothelin-1(ET-1),calcitonin gene-related peptide(CGRP),nitric ox...Objective:To observe the effects of moxibustion at different temperatures(38℃,46℃)on blood lipids,endothelial morphology of the thoracic aorta,serum endothelin-1(ET-1),calcitonin gene-related peptide(CGRP),nitric oxide(NO),and endothelial NO synthase(eNOS)in hyperlipidemic rats.Methods:Using the random number table method,60 Sprague Dawley rats were randomly and evenly divided into blank,model,38℃-moxibustion,and 46℃-moxibustion groups.Rats in the 3 experimental groups were fed a high-fat feed to model hyperlipidemia in rats.Rats in the 38℃-moxibustion and 46℃-moxibustion groups were moxibustion on the Shenque and bilateral Zusanli acupoints for 10 minutes each,once every other day for 4 weeks,at temperatures of 38±1℃ and 46±1℃.After that,rat blood samples were collected to detect blood lipids and ET-1,CGRP,eNOS and NO.Take the endotheal tissue of the thoracic aorta to do HE staining.Results:(1)The serum total cholesterol,triglycerides,and low-density lipoprotein cholesterol of rats in the 46℃-moxibustion group were significantly lower than those in the model and 38℃-moxibustion groups.(2)Revealed by hematoxylin and eosin staining,showed necrosis in the local vascular endothelial cells and mild inflammatory cell infiltration in the tunica adventitia of the hyperlipidemic rats.These endothelial morphologies did not improve significantly after moxibustion at 38℃ but did improve at 46℃.(3)Compared with the blank group,serum ET-1 was significantly higher and serum CGRP,NO,eNOS were significantly lower in the model group.Compared with the model and the 38℃-moxibustion groups,serum ET-1 was significantly lower and serum CGRP,NO,eNOS were significantly higher in 46℃-moxibustion groups.Conclusion:Moxibustion at 46℃ effectively regulated blood lipids,improved the morphology of the vascular endothelium,and protected vascular endothelial function.展开更多
AIM:To determine the expression and significance of filamin A(FLNa)in colorectal adenocarcinoma tissue.METHODS:The expression of FLNa in 46 colorectal cancer tissues and normal tissues was detected by immunohistochemi...AIM:To determine the expression and significance of filamin A(FLNa)in colorectal adenocarcinoma tissue.METHODS:The expression of FLNa in 46 colorectal cancer tissues and normal tissues was detected by immunohistochemistry,reverse transcription polymerase chain reaction(RT-PCR)and Western blotting,and its relationship with clinical parameters and prognosis was analyzed.RESULTS:The positive expression of FLNa in cancer tissues was lower than that in normal mucosa,and the difference was statistically significant.The expression of FLNa correlated with liver metastasis,lymph node metastasis and rectal invasion depth,regardless of sex,age,tumor location,tumor size,gross shape and histological type of colorectal carcinoma.Multivariate analysis showed that FLNa was an independent risk factor for postoperative survival of patients with colorectal adenocarcinoma.Moreover,survival analysis showed that the expression level of FLNa was closely related with survival of patients with colorectal adenocarcinoma.The results of RT-PCR and Western blotting were consistent with those of immunohistochemistry.CONCLUSION:FLNa showed low expression in colorectal adenocarcinoma,high correlation with the incidence and development of colorectal cancer,and was considered an indicator of prognosis.展开更多
The perovskite samples La1-x(Sr1-yKy)xMnO3 (y = 0.0, 0.2, 04, 0.6, 0.8) were prepared by the solid-state reaction method with comparatively low sintering tem- perature and with comparatively short sintering time, ...The perovskite samples La1-x(Sr1-yKy)xMnO3 (y = 0.0, 0.2, 04, 0.6, 0.8) were prepared by the solid-state reaction method with comparatively low sintering tem- perature and with comparatively short sintering time, and the electric transport property and temperature stability of MR of this system were studied. The p-T curves show the abnormal phenomenon that with the increase of K doping amount, resistivity increases, and the insulator-metal transition temperature decreases, which is because the influence of the occupation disorder degree of A-site ions σ2 on the electric transport property of perovskite manga- nites is larger than that of the radius of A-site ions (rA). In the temperature range below 225 K, MR increases contin- uously with the decrease of temperature, which is the characteristic of low-field magnetoresistance; in the com- paratively wide temperature range near 250 K, the MR- T curves of all the samples are comparatively fiat, and the value of MR almost does not change with temperature, which shows the temperature stability of magnetoresis- tance, and can be explained by the competition between the low-field magnetoresistance induced by spin-dependent tunneling of surface phase and the intrinsic magnetoresis- tance of grain phase. The magnetoresistance value of the sample with y = 0.8 keeps at (7.92 ±0.36) % in the very wide temperature range of 225-275 K, and this is a goodreference for the preparation of this kind of sample with practical application value in the future.展开更多
The samples ofLa8/9Sr1/45Na4/45MnO3 (LSNMO)/x/2(Sb2O3) were prepared by the solid-state reaction method. The electric transport properties and the temperature stabil-ity of magnetoresistance (MR) of the samples ...The samples ofLa8/9Sr1/45Na4/45MnO3 (LSNMO)/x/2(Sb2O3) were prepared by the solid-state reaction method. The electric transport properties and the temperature stabil-ity of magnetoresistance (MR) of the samples were studied through the measurements of X-ray diffraction patterns, resistivity-temperature (ρ-T) curves, mass magnetization-temperature (σ-T) curves, and magnetoresistance-temper-ature (MR-T) curves. The results indicate that the p-Tcurves of the original material LSNMO show two peaks, and the phenomenon of two peaks of ρ-T curves disappears for the composite samples, which can be explained by a competition between surface-phase resistivity induced by boundary-dependent scattering and body-phase resistivity induced by paramagnetism-ferromagnetism transition. For all the sam-ples in the low temperature range, MR increases continu-ously with the decrease of temperature, which shows a characteristic of low-field magnetoresistance. However, MR basically keeps the same in the high temperature range. The paramagnetism-ferromagnetism transition is observed in the high temperature range due to a composite between perov-skite manganite and insulator, which can enhance the tem-perature of MR appearance in the high temperature range and make it to appear near room temperature. For the sample with x = 0.12, MR remains constant at the value of 7.5 % in the temperature range of 300-260 K, which achieves a tem-perature stability of MR near room temperature. In addition,for the sample with x = 0.16, MR is above 6.8 % in the high temperature range of 318-252 K (△T = 66 K). MR almost remains constant in this temperature range, which favors the practical application of MR.展开更多
BACKGROUND Recent evidence showed that combining endoscopic submucosal dissection(ESD)and laparoscopic sentinel lymph node dissection may avoid unnecessary gastrectomy in treating early mucinous gastric cancer(EMGC)pa...BACKGROUND Recent evidence showed that combining endoscopic submucosal dissection(ESD)and laparoscopic sentinel lymph node dissection may avoid unnecessary gastrectomy in treating early mucinous gastric cancer(EMGC)patients with risks of positive lymph node metastasis(pLNM).AIM To explore the predictive factors for pLNM in EMGC,and to optimize the clinical application of combing ESD and sentinel lymph node dissection in a proper subgroup of patients with EMGC.METHODS Thirty-one patients with EMGC who had undergone gastrectomy with lymph node dissection were consecutively enrolled from January 1988 to December 2016.Univariate and multivariate logistic regression analyses were used to estimate the association between the rates of pLNM and clinicopathological factors,providing odds ratio(OR)with 95%confidence interval.And the association between the number of predictors and the pLNM rate was also investigated.RESULTS Depth of invasion(OR=7.342,1.127-33.256,P=0.039),tumor diameter(OR=9.158,1.348-29.133,P=0.044),and lymphatic vessel involvement(OR=27.749,1.821-33.143,P=0.019)turned out to be significant and might be the independent risk factors for predicating pLNM in the multivariate analysis.For patients with 1,2,and 3 risk factors,the pLNM rates were 9.1%,33.3%,and 75.0%,respectively.pLNM was not detected in seven patients without any of these risk factors.CONCLUSION ESD might serve as a safe and sufficient treatment for intramucosal EMGC if tumor size≤2 cm,and when lymphatic vessel involvement is absent by postoperative histological examination.Combining ESD and sentinel lymph node dissection could be recommended as a safe and effective treatment for EMGC patients with a potential risk of pLNM.展开更多
Largescale vaporsolid synthesis of ultralong silicon nitride (Si3N4) nanowires was achieved by using simple thermal evaporation of mixture powders of active carbon and monoxide silicon. The products were charac teri...Largescale vaporsolid synthesis of ultralong silicon nitride (Si3N4) nanowires was achieved by using simple thermal evaporation of mixture powders of active carbon and monoxide silicon. The products were charac terized by Xray diffraction, scanning electron microscopy, energydispersive Xray spectroscopy, and transmission electron microscopy. The results suggest that the silicon nitride nanowires have a smooth surface, with lengths of up to several hundreds of microns and diameters of 100300 nm. A detailed study of both the chemical and structural composition was performed. Such ultralong sil icon nitride nanowires demonstrate potential applications as materials for constructing nanoscale devices and as reinforcement in advanced composites.展开更多
Objective: To study the impacts of exposure to electromagnetic radiation(EMR) on liver function in rats. Methods: Twenty adult male Sprague-Dawley rats were randomly divided into normal group and radiated group. The r...Objective: To study the impacts of exposure to electromagnetic radiation(EMR) on liver function in rats. Methods: Twenty adult male Sprague-Dawley rats were randomly divided into normal group and radiated group. The rats in normal group were not radiated, those in radiated group were exposed to EMR 4 h/d for 18 consecutive days. Rats were sacrificed immediately after the end of the experiment. The serum levels of alanine aminotransferase(ALT) and aspartate aminotransferase(AST), and those of malondialdehyde(MDA) and glutathione(GSH) in liver tissue were evaluated by colorimetric method. The liver histopathological changes were observed by hematoxylin and eosin staining and the protein expression of bax and bcl-2 in liver tissue were detected by immunohistochemical method. Terminal-deoxynucleotidyl transferase mediated nick and labelling(TUNEL) method was used for analysis of apoptosis in liver. Results: Compared with the normal rats, the serum levels of ALT and AST in the radiated group had no obvious changes(P>0.05), while the contents of MDA increased(P<0.01) and those of GSH decreased(P<0.01) in liver tissues. The histopathology examination showed diffuse hepatocyte swelling and vacuolation, small pieces and focal necrosis. The immunohistochemical results displayed that the expression of the bax protein was higher and that of bcl-2 protein was lower in radiated group. The hepatocyte apoptosis rates in radiated group was higher than that in normal group(all P<0.01). Conclusion: The exposure to 900 MHz mobile phone 4 h/d for 18 days could induce the liver histological changes, which may be partly due to the apoptosis and oxidative stress induced in liver tissue by electromagnetic radiation.展开更多
Polycrystalline samples of Lal-x(Srl-yAgy)x MnO3 (y = 0.0, 0.2, 0.4, 0.6, 1.0) were prepared by the solid-state reaction method. The temperature stability of magnetoresistance and magnetoresistance enhancement in ...Polycrystalline samples of Lal-x(Srl-yAgy)x MnO3 (y = 0.0, 0.2, 0.4, 0.6, 1.0) were prepared by the solid-state reaction method. The temperature stability of magnetoresistance and magnetoresistance enhancement in Lal_x(Srl_yAgy)~MnO3 system with both univalent and bivalent elements doped at A site and with unchanged value of Mn~+/Mn4+ ratio were explored through the measurements of X-ray diffraction patterns, magnetiza- tion-temperature (M-T) curves, resistivity-temperature (p-T) curves and magnetoresistance-temperature (MR-T) curves. The results are as follows: there are two peaks in the p-T curves of the samples with Ag doping, one is caused by resistance change during the paramagnetism- ferromagnetism transition, and the other is from boundary- dependent scattering of conduction electrons on the boundaries of grains. The peak value of MR increases with increasing Ag doping content, and it increases from 8.2 % for y ---- 0.2 to 29.6 % for y ---- 1.0 under the magnetic field of B = 0.8 T; MR remains a constant of 12 % in the temperature range of 218-168 K for the sample with y = 1.0, and the temperature stability of MR is in favor of the practical application of MR.展开更多
Background: An artificial intelligence system of Faster Region-based Convolutional Neural Network (Faster R-CNN) is newly developed for the diagnosis of metastatic lymph node (LN) in rectal cancer patients. The primar...Background: An artificial intelligence system of Faster Region-based Convolutional Neural Network (Faster R-CNN) is newly developed for the diagnosis of metastatic lymph node (LN) in rectal cancer patients. The primary objective of this study was to comprehensively verify its accuracy in clinical use. Methods: Four hundred fourteen patients with rectal cancer discharged between January 2013 and March 2015 were collected from 6 clinical centers, and the magnetic resonance imaging data for pelvic metastatic LNs of each patient was identified by Faster R-CNN. Faster R-CNN based diagnoses were compared with radiologist based diagnoses and pathologist based diagnoses for methodological verification, using correlation analyses and consistency check. For clinical verification, the patients were retrospectively followed up by telephone for 36 months, with post-operative recurrence of rectal cancer as a clinical outcome;recurrence-free survivals of the patients were compared among different diagnostic groups, by methods of Kaplan-Meier and Cox hazards regression model. Results: Significant correlations were observed between any 2 factors among the numbers of metastatic LNs separately diagnosed by radiologists, Faster R-CNN and pathologists, as evidenced by rradiologist-Faster R-CNN of 0.912, rPathologist-radiologist of 0.134, and rPathologist-Faster R-CNN of 0.448 respectively. The value of kappa coefficient in N staging between Faster R-CNN and pathologists was 0.573, and this value between radiologists and pathologists was 0.473. The 3 groups of Faster R-CNN, radiologists and pathologists showed no significant differences in the recurrence-free survival time for stage N0 and N1 patients, but significant differences were found for stage N2 patients. Conclusion: Faster R-CNN surpasses radiologists in the evaluation of pelvic metastatic LNs of rectal cancer, but is not on par with pathologists.展开更多
The samples of La0.80Sr0.15Ag0.05MnO3/x(CuO) (x = 0, 0.05, 0.10, 0.15, 0.20) were prepared by the solid-state reaction method, and the structure of the sampies was detected by X-ray diffraction (XRD), scanning e...The samples of La0.80Sr0.15Ag0.05MnO3/x(CuO) (x = 0, 0.05, 0.10, 0.15, 0.20) were prepared by the solid-state reaction method, and the structure of the sampies was detected by X-ray diffraction (XRD), scanning electron microscope (SEM) equipped with energy dispersive spectroscopy (EDS), electric transport mechanism, and magnetoresistance enhancement, and the temperature stability of magnetoresistance of the samples was studied through resistivity-temperature (ρ-T) curves, ρ-T fitted curves, and magnetoresistance-temperature (MR-T) curves. The results indicate that ρ-T data can be fitted by the formula ρ = ρ0 + AT^2 very well, and the electric transport mechanism of all the samples in metal-like area is the scattering of single magneton upon spin electron; the magnetoresistance of composite samples is far larger than that of the original material, and the MR peak value of the sample with x = 0.20 is nearly 4 times as large as that of the sample with x = 0; composite samples have comparatively good temperature stability of magnetoresistance in the temperature range of 200-260 K, and the magnetoresistance of the sample with x = 0.15 almost does not change with temperature and keeps at (5.03 ± 0.20) % in the temperature range of 210-260 K.展开更多
Development and Application of Artificial Intelligence Recognition Systems in Rectal Cancer Staging Whether for surgical treatment or for neoadjuvant chemoradiotherapy,imaging evaluation has become an important basis ...Development and Application of Artificial Intelligence Recognition Systems in Rectal Cancer Staging Whether for surgical treatment or for neoadjuvant chemoradiotherapy,imaging evaluation has become an important basis to perform the treatment plans.[1]The reading of imaging results requires a large number of experienced radiologists to complete,but shortages and uneven distributions of personnel cause delays and biases in imaging results.Therefore,independent research and development of automatic recognition systems of rectal cancer staging based on artificial intelligence(AI)platforms aim to partially replace practitioners’work and achieve rapid and accurate identification of rectal cancer staging.展开更多
基金Supported by Hebei Provincial Health Commission Youth Science and Technology Project,No.20210027.
文摘BACKGROUND Colorectal cancer(CRC)is the third most common cancer and a significant cause of cancer-related mortality globally.Resistance to chemotherapy,especially during CRC treatment,leads to reduced effectiveness of drugs and poor patient outcomes.Long noncoding RNAs(lncRNAs)have been implicated in various pathophysiological processes of tumor cells,including chemotherapy resistance,yet the roles of many lncRNAs in CRC remain unclear.AIM To identify and analyze the lncRNAs involved in oxaliplatin resistance in CRC and to understand the underlying molecular mechanisms influencing this resistance.METHODS Gene Expression Omnibus datasets GSE42387 and GSE30011 were reanalyzed to identify lncRNAs and mRNAs associated with oxaliplatin resistance.Various bioinformatics tools were employed to elucidate molecular mechanisms.The expression levels of lncRNAs and mRNAs were assessed via quantitative reverse transcription-polymerase chain reaction.Functional assays,including MTT,wound healing,and Transwell,were conducted to investigate the functional implications of lncRNA alterations.Interactions between lncRNAs and trans-cription factors were examined using RIP and luciferase reporter assays,while Western blotting was used to confirm downstream pathways.Additionally,a xenograft mouse model was utilized to study the in vivo effects of lncRNAs on chemotherapy resistance.RESULTS LncRNA prion protein testis specific(PRNT)was found to be upregulated in oxaliplatin-resistant CRC cell lines and negatively correlated with homeodomain interacting protein kinase 2(HIPK2)expression.PRNT was demonstrated to sponge transcription factor zinc finger protein 184(ZNF184),which in turn could regulate HIPK2 expression.Altered expression of PRNT influenced CRC cell sensitivity to oxaliplatin,with overexpression leading to decreased sensitivity and decreased expression reducing resistance.Both RIP and luciferase reporter assays indicated that ZNF184 and HIPK2 are targets of PRNT.The PRNT/ZNF184/HIPK2 axis was implicated in promoting CRC progression and oxaliplatin resistance both in vitro and in vivo.CONCLUSION The study concludes that PRNT is upregulated in oxaliplatin-resistant CRC cells and modulates the expression of HIPK2 by sponging ZNF184.This regulatory mechanism enhances CRC progression and resistance to oxaliplatin,positioning PRNT as a promising therapeutic target for CRC patients undergoing oxaliplatin-based chemotherapy.
基金This work was supported by National Natural Science Foundation of China(NO.81603695).
文摘Objective:To observe the effects of moxibustion at different temperatures(38℃,46℃)on blood lipids,endothelial morphology of the thoracic aorta,serum endothelin-1(ET-1),calcitonin gene-related peptide(CGRP),nitric oxide(NO),and endothelial NO synthase(eNOS)in hyperlipidemic rats.Methods:Using the random number table method,60 Sprague Dawley rats were randomly and evenly divided into blank,model,38℃-moxibustion,and 46℃-moxibustion groups.Rats in the 3 experimental groups were fed a high-fat feed to model hyperlipidemia in rats.Rats in the 38℃-moxibustion and 46℃-moxibustion groups were moxibustion on the Shenque and bilateral Zusanli acupoints for 10 minutes each,once every other day for 4 weeks,at temperatures of 38±1℃ and 46±1℃.After that,rat blood samples were collected to detect blood lipids and ET-1,CGRP,eNOS and NO.Take the endotheal tissue of the thoracic aorta to do HE staining.Results:(1)The serum total cholesterol,triglycerides,and low-density lipoprotein cholesterol of rats in the 46℃-moxibustion group were significantly lower than those in the model and 38℃-moxibustion groups.(2)Revealed by hematoxylin and eosin staining,showed necrosis in the local vascular endothelial cells and mild inflammatory cell infiltration in the tunica adventitia of the hyperlipidemic rats.These endothelial morphologies did not improve significantly after moxibustion at 38℃ but did improve at 46℃.(3)Compared with the blank group,serum ET-1 was significantly higher and serum CGRP,NO,eNOS were significantly lower in the model group.Compared with the model and the 38℃-moxibustion groups,serum ET-1 was significantly lower and serum CGRP,NO,eNOS were significantly higher in 46℃-moxibustion groups.Conclusion:Moxibustion at 46℃ effectively regulated blood lipids,improved the morphology of the vascular endothelium,and protected vascular endothelial function.
基金Supported by Hebei Province Health Department of China,No.14277710D and No.GL2012050
文摘AIM:To determine the expression and significance of filamin A(FLNa)in colorectal adenocarcinoma tissue.METHODS:The expression of FLNa in 46 colorectal cancer tissues and normal tissues was detected by immunohistochemistry,reverse transcription polymerase chain reaction(RT-PCR)and Western blotting,and its relationship with clinical parameters and prognosis was analyzed.RESULTS:The positive expression of FLNa in cancer tissues was lower than that in normal mucosa,and the difference was statistically significant.The expression of FLNa correlated with liver metastasis,lymph node metastasis and rectal invasion depth,regardless of sex,age,tumor location,tumor size,gross shape and histological type of colorectal carcinoma.Multivariate analysis showed that FLNa was an independent risk factor for postoperative survival of patients with colorectal adenocarcinoma.Moreover,survival analysis showed that the expression level of FLNa was closely related with survival of patients with colorectal adenocarcinoma.The results of RT-PCR and Western blotting were consistent with those of immunohistochemistry.CONCLUSION:FLNa showed low expression in colorectal adenocarcinoma,high correlation with the incidence and development of colorectal cancer,and was considered an indicator of prognosis.
基金financially supported by the National Natural Science Foundation of China (No. 19934003)the Key Program of Natural Science Foundation of Anhui Province (Nos. KJ2011A259 and KJ2013A245)+1 种基金the Program of Professors and Doctors' Research Startup Foundation of Suzhou College (Nos. 2011jb01 and 2011jb02)the Program of Cultivating Base of Anhui Key Laboratory of Spintronics and Nano-materials Research (No. 2012YKF09)
文摘The perovskite samples La1-x(Sr1-yKy)xMnO3 (y = 0.0, 0.2, 04, 0.6, 0.8) were prepared by the solid-state reaction method with comparatively low sintering tem- perature and with comparatively short sintering time, and the electric transport property and temperature stability of MR of this system were studied. The p-T curves show the abnormal phenomenon that with the increase of K doping amount, resistivity increases, and the insulator-metal transition temperature decreases, which is because the influence of the occupation disorder degree of A-site ions σ2 on the electric transport property of perovskite manga- nites is larger than that of the radius of A-site ions (rA). In the temperature range below 225 K, MR increases contin- uously with the decrease of temperature, which is the characteristic of low-field magnetoresistance; in the com- paratively wide temperature range near 250 K, the MR- T curves of all the samples are comparatively fiat, and the value of MR almost does not change with temperature, which shows the temperature stability of magnetoresis- tance, and can be explained by the competition between the low-field magnetoresistance induced by spin-dependent tunneling of surface phase and the intrinsic magnetoresis- tance of grain phase. The magnetoresistance value of the sample with y = 0.8 keeps at (7.92 ±0.36) % in the very wide temperature range of 225-275 K, and this is a goodreference for the preparation of this kind of sample with practical application value in the future.
基金financially supported by the National Natural Science Foundation of China(No.19934003)the Natural Science Foundation of the Education Bureau of Anhui Province,China(Nos.KJ2011A259 and KJ2012Z404)+1 种基金Anhui Key Laboratory of Spintronics and Nano-materials Program(Nos.2010YKF01 and 2010YKF04)the Professors’and Doctors’ Research Startup Foundation of Suzhou University(Nos.2011jb01 and 2010jb02)
文摘The samples ofLa8/9Sr1/45Na4/45MnO3 (LSNMO)/x/2(Sb2O3) were prepared by the solid-state reaction method. The electric transport properties and the temperature stabil-ity of magnetoresistance (MR) of the samples were studied through the measurements of X-ray diffraction patterns, resistivity-temperature (ρ-T) curves, mass magnetization-temperature (σ-T) curves, and magnetoresistance-temper-ature (MR-T) curves. The results indicate that the p-Tcurves of the original material LSNMO show two peaks, and the phenomenon of two peaks of ρ-T curves disappears for the composite samples, which can be explained by a competition between surface-phase resistivity induced by boundary-dependent scattering and body-phase resistivity induced by paramagnetism-ferromagnetism transition. For all the sam-ples in the low temperature range, MR increases continu-ously with the decrease of temperature, which shows a characteristic of low-field magnetoresistance. However, MR basically keeps the same in the high temperature range. The paramagnetism-ferromagnetism transition is observed in the high temperature range due to a composite between perov-skite manganite and insulator, which can enhance the tem-perature of MR appearance in the high temperature range and make it to appear near room temperature. For the sample with x = 0.12, MR remains constant at the value of 7.5 % in the temperature range of 300-260 K, which achieves a tem-perature stability of MR near room temperature. In addition,for the sample with x = 0.16, MR is above 6.8 % in the high temperature range of 318-252 K (△T = 66 K). MR almost remains constant in this temperature range, which favors the practical application of MR.
文摘BACKGROUND Recent evidence showed that combining endoscopic submucosal dissection(ESD)and laparoscopic sentinel lymph node dissection may avoid unnecessary gastrectomy in treating early mucinous gastric cancer(EMGC)patients with risks of positive lymph node metastasis(pLNM).AIM To explore the predictive factors for pLNM in EMGC,and to optimize the clinical application of combing ESD and sentinel lymph node dissection in a proper subgroup of patients with EMGC.METHODS Thirty-one patients with EMGC who had undergone gastrectomy with lymph node dissection were consecutively enrolled from January 1988 to December 2016.Univariate and multivariate logistic regression analyses were used to estimate the association between the rates of pLNM and clinicopathological factors,providing odds ratio(OR)with 95%confidence interval.And the association between the number of predictors and the pLNM rate was also investigated.RESULTS Depth of invasion(OR=7.342,1.127-33.256,P=0.039),tumor diameter(OR=9.158,1.348-29.133,P=0.044),and lymphatic vessel involvement(OR=27.749,1.821-33.143,P=0.019)turned out to be significant and might be the independent risk factors for predicating pLNM in the multivariate analysis.For patients with 1,2,and 3 risk factors,the pLNM rates were 9.1%,33.3%,and 75.0%,respectively.pLNM was not detected in seven patients without any of these risk factors.CONCLUSION ESD might serve as a safe and sufficient treatment for intramucosal EMGC if tumor size≤2 cm,and when lymphatic vessel involvement is absent by postoperative histological examination.Combining ESD and sentinel lymph node dissection could be recommended as a safe and effective treatment for EMGC patients with a potential risk of pLNM.
基金supported by the Key Program of the National Natural Science Foundation of China(No.19934003)the Grand Program of Natural Science Research of Anhui Education Department(No.ZD2007003-1)+1 种基金the Natural Science Research Program of Universities and Colleges of Anhui Province(No.KJ2008A19ZC)the Opening Program of Cultivating Baseof Anhui Key Laboratory of Spintronics and Nano-materials(No.2012YKF10)
文摘Largescale vaporsolid synthesis of ultralong silicon nitride (Si3N4) nanowires was achieved by using simple thermal evaporation of mixture powders of active carbon and monoxide silicon. The products were charac terized by Xray diffraction, scanning electron microscopy, energydispersive Xray spectroscopy, and transmission electron microscopy. The results suggest that the silicon nitride nanowires have a smooth surface, with lengths of up to several hundreds of microns and diameters of 100300 nm. A detailed study of both the chemical and structural composition was performed. Such ultralong sil icon nitride nanowires demonstrate potential applications as materials for constructing nanoscale devices and as reinforcement in advanced composites.
基金supported by the Natural Science Foundation of Hebei Province(201220123)Youth Fund Project of He Bei University of Chinese Medicine(QNZ2014015)
文摘Objective: To study the impacts of exposure to electromagnetic radiation(EMR) on liver function in rats. Methods: Twenty adult male Sprague-Dawley rats were randomly divided into normal group and radiated group. The rats in normal group were not radiated, those in radiated group were exposed to EMR 4 h/d for 18 consecutive days. Rats were sacrificed immediately after the end of the experiment. The serum levels of alanine aminotransferase(ALT) and aspartate aminotransferase(AST), and those of malondialdehyde(MDA) and glutathione(GSH) in liver tissue were evaluated by colorimetric method. The liver histopathological changes were observed by hematoxylin and eosin staining and the protein expression of bax and bcl-2 in liver tissue were detected by immunohistochemical method. Terminal-deoxynucleotidyl transferase mediated nick and labelling(TUNEL) method was used for analysis of apoptosis in liver. Results: Compared with the normal rats, the serum levels of ALT and AST in the radiated group had no obvious changes(P>0.05), while the contents of MDA increased(P<0.01) and those of GSH decreased(P<0.01) in liver tissues. The histopathology examination showed diffuse hepatocyte swelling and vacuolation, small pieces and focal necrosis. The immunohistochemical results displayed that the expression of the bax protein was higher and that of bcl-2 protein was lower in radiated group. The hepatocyte apoptosis rates in radiated group was higher than that in normal group(all P<0.01). Conclusion: The exposure to 900 MHz mobile phone 4 h/d for 18 days could induce the liver histological changes, which may be partly due to the apoptosis and oxidative stress induced in liver tissue by electromagnetic radiation.
基金financially supported by the National Natural Science Foundation of China(NSFC)(No.19934003)the Key Program of Natural Science Foundation of Anhui Province(No.KJ2011A259)+1 种基金the Program of Professors and Doctors'Research Startup Foundation of Suzhou College(Nos.2011jb01 and 2011jb02)the Cultivating Base of Anhui Key Laboratory of Spintronics and Nano-materials Research Program(No.2010YKF04)
文摘Polycrystalline samples of Lal-x(Srl-yAgy)x MnO3 (y = 0.0, 0.2, 0.4, 0.6, 1.0) were prepared by the solid-state reaction method. The temperature stability of magnetoresistance and magnetoresistance enhancement in Lal_x(Srl_yAgy)~MnO3 system with both univalent and bivalent elements doped at A site and with unchanged value of Mn~+/Mn4+ ratio were explored through the measurements of X-ray diffraction patterns, magnetiza- tion-temperature (M-T) curves, resistivity-temperature (p-T) curves and magnetoresistance-temperature (MR-T) curves. The results are as follows: there are two peaks in the p-T curves of the samples with Ag doping, one is caused by resistance change during the paramagnetism- ferromagnetism transition, and the other is from boundary- dependent scattering of conduction electrons on the boundaries of grains. The peak value of MR increases with increasing Ag doping content, and it increases from 8.2 % for y ---- 0.2 to 29.6 % for y ---- 1.0 under the magnetic field of B = 0.8 T; MR remains a constant of 12 % in the temperature range of 218-168 K for the sample with y = 1.0, and the temperature stability of MR is in favor of the practical application of MR.
文摘Background: An artificial intelligence system of Faster Region-based Convolutional Neural Network (Faster R-CNN) is newly developed for the diagnosis of metastatic lymph node (LN) in rectal cancer patients. The primary objective of this study was to comprehensively verify its accuracy in clinical use. Methods: Four hundred fourteen patients with rectal cancer discharged between January 2013 and March 2015 were collected from 6 clinical centers, and the magnetic resonance imaging data for pelvic metastatic LNs of each patient was identified by Faster R-CNN. Faster R-CNN based diagnoses were compared with radiologist based diagnoses and pathologist based diagnoses for methodological verification, using correlation analyses and consistency check. For clinical verification, the patients were retrospectively followed up by telephone for 36 months, with post-operative recurrence of rectal cancer as a clinical outcome;recurrence-free survivals of the patients were compared among different diagnostic groups, by methods of Kaplan-Meier and Cox hazards regression model. Results: Significant correlations were observed between any 2 factors among the numbers of metastatic LNs separately diagnosed by radiologists, Faster R-CNN and pathologists, as evidenced by rradiologist-Faster R-CNN of 0.912, rPathologist-radiologist of 0.134, and rPathologist-Faster R-CNN of 0.448 respectively. The value of kappa coefficient in N staging between Faster R-CNN and pathologists was 0.573, and this value between radiologists and pathologists was 0.473. The 3 groups of Faster R-CNN, radiologists and pathologists showed no significant differences in the recurrence-free survival time for stage N0 and N1 patients, but significant differences were found for stage N2 patients. Conclusion: Faster R-CNN surpasses radiologists in the evaluation of pelvic metastatic LNs of rectal cancer, but is not on par with pathologists.
基金financially supported by the Key Program of National Natural Science Foundation of China(No.19934003)the Program of Natural Science Foundation of Anhui Province(No.1308085MA11)+1 种基金the Key Programs of Natural Science Research of Anhui Education Department(Nos.KJ2013A245 and KJ2012Z404)the Open Projects of Anhui Key Laboratory of Spintronic and Nanometric Materials(Nos.2012YKF09,2012YKF10,and 2012YKF08)
文摘The samples of La0.80Sr0.15Ag0.05MnO3/x(CuO) (x = 0, 0.05, 0.10, 0.15, 0.20) were prepared by the solid-state reaction method, and the structure of the sampies was detected by X-ray diffraction (XRD), scanning electron microscope (SEM) equipped with energy dispersive spectroscopy (EDS), electric transport mechanism, and magnetoresistance enhancement, and the temperature stability of magnetoresistance of the samples was studied through resistivity-temperature (ρ-T) curves, ρ-T fitted curves, and magnetoresistance-temperature (MR-T) curves. The results indicate that ρ-T data can be fitted by the formula ρ = ρ0 + AT^2 very well, and the electric transport mechanism of all the samples in metal-like area is the scattering of single magneton upon spin electron; the magnetoresistance of composite samples is far larger than that of the original material, and the MR peak value of the sample with x = 0.20 is nearly 4 times as large as that of the sample with x = 0; composite samples have comparatively good temperature stability of magnetoresistance in the temperature range of 200-260 K, and the magnetoresistance of the sample with x = 0.15 almost does not change with temperature and keeps at (5.03 ± 0.20) % in the temperature range of 210-260 K.
基金International Practice Guideline Registry(No.IPGRP-2020CN175).
文摘Development and Application of Artificial Intelligence Recognition Systems in Rectal Cancer Staging Whether for surgical treatment or for neoadjuvant chemoradiotherapy,imaging evaluation has become an important basis to perform the treatment plans.[1]The reading of imaging results requires a large number of experienced radiologists to complete,but shortages and uneven distributions of personnel cause delays and biases in imaging results.Therefore,independent research and development of automatic recognition systems of rectal cancer staging based on artificial intelligence(AI)platforms aim to partially replace practitioners’work and achieve rapid and accurate identification of rectal cancer staging.