Aim: To study the relationship between Ureaplasma urealyticum (UU) infection and apoptosis of human spermato-genic cells. Methods: Spermatogenic cells were observed under light microscope with Wright-Giemsa staining a...Aim: To study the relationship between Ureaplasma urealyticum (UU) infection and apoptosis of human spermato-genic cells. Methods: Spermatogenic cells were observed under light microscope with Wright-Giemsa staining andby means of terminal deoxynucleotidyl transferase-mediated deoxyuridine triphosphate (dUTP)-biotin nick-end labeling(TUNEL) technique. Results: Apoptotic rate of UU-infected males (15.5 % ± 6.8 % ) was significantly higherthan that of controls (5.2 % ± 2.3 % ). Conclusion: Apoptosis of spermatogenic cells can be caused by UU in-fection, which provides further evidence for UU-induced male infertility. (Asian J Androl 1999 Sep ; 1: 127 - 129)展开更多
A novel diffusion couple method was used to investigate the interface diffusion of arsenic into a Nb-Ti microalloyed low carbon steel and its effects on phase transformation at the interface. It is discovered that the...A novel diffusion couple method was used to investigate the interface diffusion of arsenic into a Nb-Ti microalloyed low carbon steel and its effects on phase transformation at the interface. It is discovered that the content of arsenic has great effect on grain growth and phase transformation at high temperature. When the arsenic content is no more than lwt%, there is no obvious grain growth and no obvious ferrite transitional region formed at the diffusion interface. However, when the arsenic content is no less than 5wt%, the grain grows very rapidly. In addition, the arsenic-enriched ferrite transitional layer forms at the diffusion interface in the hot-rolling process, which results from a slower diffusion rate of arsenic atoms than that of carbon in ferrite.展开更多
Auger electron spectroscopy (AES) was used to investigate the grain boundary segregation of arsenic and nitrogen in a kind of microalloyed steel produced by a compact strip production (CSP) technology at 950 to 1...Auger electron spectroscopy (AES) was used to investigate the grain boundary segregation of arsenic and nitrogen in a kind of microalloyed steel produced by a compact strip production (CSP) technology at 950 to 1100℃, which are similar to the hot working temperature of the steel on a CSP production line. It was discovered that arsenic segregated on grain boundaries when the steel was annealed at 950℃ for 2 h. When the annealing temperature increased to 1100℃, arsenic was also found to have segregated on grain boundaries in the early annealing stage, for instance, within the first 5 min annealing time. However, if the holding time of the steel at this temperature increased to 2 h, arsenic diffused away from grain boundaries into the matrix again. Nitrogen was not found to have segregated on grain boundaries when the steel was annealed at a relatively low temperature, such as 950℃. But when the annealing temperature increased to 1100℃, nitrogen was detected to have segregated at grain boundaries in the steel.展开更多
A chaos control strategy for chaotic current-mode boost converter is presented by using inductor current sampled feedback control technique.The quantitative analysis of control mechanism is performed by establishing a...A chaos control strategy for chaotic current-mode boost converter is presented by using inductor current sampled feedback control technique.The quantitative analysis of control mechanism is performed by establishing a discrete alterative map of the controlled system.The stability criterion,feedback gain,and corresponding critical duty ratio are obtained from the eigenvalue of the map.The simulation results verify the t heoretical analysis results of the control strategy.展开更多
BACKGROUND Data that assess maternal and infant outcomes in hepatitis C virus(HCV)-infected mothers are limited.AIM To investigate the frequency of complications and the associated risk factors.METHODS We performed a ...BACKGROUND Data that assess maternal and infant outcomes in hepatitis C virus(HCV)-infected mothers are limited.AIM To investigate the frequency of complications and the associated risk factors.METHODS We performed a cohort study to compare pregnancy and fetal outcomes of HCVviremic mothers with those of healthy mothers.Risk factors were analyzed with logistic regression.RESULTS Among 112 consecutive HCV antibody-positive mothers screened,we enrolled 79 viremic mothers.We randomly selected 115 healthy mothers from the birth registry as the control.Compared to healthy mothers,HCV mothers had a significantly higher frequency of anemia[2.6%(3/115)vs 19.0%(15/79),P<0.001]during pregnancy,medical conditions that required caesarian section[27.8%(32/115)vs 48.1%(38/79),P=0.004],and nuchal cords[9.6%(11/115)vs 34.2%(27/79),P<0.001].In addition,the mean neonatal weight in the HCV group was significantly lower(3278.3±462.0 vs 3105.1±459.4 gms;P=0.006),and the mean head circumference was smaller(33.3±0.6 vs 33.1±0.7 cm;P=0.03).In a multivariate model,HCV-infected mothers were more likely to suffer anemia[adjusted odds ratio(OR):18.1,95%confidence interval(CI):4.3-76.6],require caesarian sections(adjusted OR:2.6,95%CI:1.4-4.9),and have nuchal cords(adjusted OR:5.6,95%CI:2.4-13.0).Their neonates were also more likely to have smaller head circumferences(adjusted OR:2.1,95%CI:1.1-4.3)and lower birth weights than the average(≤3250 gms)with an adjusted OR of 2.2(95%CI:1.2-4.0).The vertical transmission rate was 1%in HCV-infected mothers.CONCLUSION Maternal HCV infections may associate with pregnancy and obstetric complications.We demonstrated a previously unreported association between maternal HCV viremia and a smaller neonatal head circumference,suggesting fetal growth restriction.展开更多
A deconpling control strategy of inverter parallel system is proposed based on the equivalent output impedance of single phase voltage source SPWM (sinusoidal pulse width modulation) inverter. The active power and r...A deconpling control strategy of inverter parallel system is proposed based on the equivalent output impedance of single phase voltage source SPWM (sinusoidal pulse width modulation) inverter. The active power and reactive power are calculated in terms of output voltage and current of the inverter, and sent to the other inverters in the parallel system via controller area network (CAN) bus. By calculating and decoupling the circumfluence of the active power and reactive power, the inverters can share load current via the regulation of the reference-signal phase and amplitude. Experimental results of an 110V/2kVA inverter parallel system show the feasibility of the decoupling control strategy.展开更多
Fungi of the family Boletaceae are of great importance in both ecology and economy.Our previous molecular phylogenetic studies have shown this family to have an extremely high species diversity in China.To further doc...Fungi of the family Boletaceae are of great importance in both ecology and economy.Our previous molecular phylogenetic studies have shown this family to have an extremely high species diversity in China.To further document the Chinese boletes,morphological studies and phylogenetic analyses were conducted including species of Boletaceae from China and other parts of the world.The results indicate that seven subfamily-level major clades and 62 generic clades can be retrieved,52 of which are found in China.Furthermore,100 species(comprising 32 genera)common in China are illustrated and described here in detail.Among them,four genera and 46 species are new to science,and 26 new combinations are proposed.To interpret the species concepts consistently,epitypes for five species are designated based on collections made from or near the type localities.Notes on eight extralimital species are also provided.Among the species reported here,most of the species are known only from East Asia.Only Leccinum scabrum(Bull.)Gray,Porphyrellus porphyrosporus(Fr.&Hok)E.-J.Gilbert and Tylopilus felleus(Bull.)P.Karst.are widely distributed in the Holarctic,and Buchwaldoboletus lignicola(Kallenb.)Pila´t;Strobilomyces strobilaceus(Scop.)Berk.are in Eurasia;while Aureoboletus mirabilis(Murrill)Halling,Harrya chromapes(Frost)Halling et al.,and Sutorius eximius(Peck)Halling et al.are found throughout East Asia-North America based on morphological and molecular phylogenetic evidences.展开更多
Background: Recent studies have indicated that an imbalance of gut microbiota is associated with the development of type 1 diabetes mellitus (TI DM) and there is no literature regarding it in Chinese children yet. ...Background: Recent studies have indicated that an imbalance of gut microbiota is associated with the development of type 1 diabetes mellitus (TI DM) and there is no literature regarding it in Chinese children yet. The aim of this study was to evaluate the alteration of gut microbiota between children with newly diagnosed T 1DM and healthy controls and to determine if gut microbiota could partly explain the etiology of this disease. Methods: A case-control study was carried out with 15 children with T 1 DM and 15 healthy children. The fecal bacteria composition was investigated by high-throughput sequencing of the V3-V4 region of the 16S rDNA gene and analyzed by the estimators of community richness (Chao) indexes. Results: There was a notable lower richness of fecal bacteria in T1DM group than controls (156.53 ± 36.96 vs. 130.0 ± 32.85, P - 0.047). At the genus level, the composition of Blautia was increased in T 1 DM group than control group whereas the composition of Haemophilus, Lachnospira, Dialister, and Acidaminococcus was decreased. In addition, we found that the percentage of Blautia was correlated positively with HbA 1 c (p = 0.40, P - 0.031), the numbers of T1DM autoantibodies (p = 0.42, P = 0.023), and the titers of tyrosine phosphatase autoantibodies (IA-2) (p= 0.82, P = 0.000) in the study. Conclusions: This study showed that gut microbiota was associated with the development of T 1DM by affecting the autoimmunity, and the results suggested a potential therapy for T1DM via modulating the gut microbiota.展开更多
Background:The incidence of Ebstein's anomaly is extremely low,and except for the Mayo Clinic,no cardiac center has reported on a sufficient number of patients.The aim of our study was to report the outcomes of Ebst...Background:The incidence of Ebstein's anomaly is extremely low,and except for the Mayo Clinic,no cardiac center has reported on a sufficient number of patients.The aim of our study was to report the outcomes of Ebstein's anomaly patients treated with tricuspid valvuloplasty (TVP) or tricuspid valve replacement (TVR).Methods:TVP or TV R was performed in 245 patients from July 2006 to April 2016.We reviewed patients' records and contacted patients via outpatient service and over the telephone.Results:The mean follow-up time was 43.6 ± 32.6 months,and 224 (91.4%) patients underwent follow-up.The mean operative age was 31.2 ± 15.7 years.TVR was performed in 23 patients,and TVP was performed in 201 patients.The 30-day mortality rate was 1.3%,and the overall survival rate was 97.9% at 5 and l0 years.The early mortality rate of the TVP group was lower than that of the TVR group (0.5% vs.8.7%,P =0.028),and the overall mortality rate of the TVP group was lower than that of the TVR group,without statistical significance (1.0% vs.8.7%).After propensity score matching,the rates of mortality and New York Heart Association class ≥Ⅲ were lower in the TVP group than those in the TVR group without statistical significance.Seven patients with Type B Wolff-Parkinson-White (WPW) syndrome underwent one-stage surgery,and arrhythmias disappeared.Six patients suffered from episodes of left ventricular outflow tract obstruction (LVOTO) during surgery.Severe LVOTO could be treated with reoperation of the atrialized right ventricle.Conclusions:Ebstein's anomaly patients treated with TVP or TVR can experience optimal outcomes with midterm follow-up.However,TVP should be the first-choice treatment.Optimal outcomes can be obtained from one-stage operation in patients with Type B WPW syndrome.Severe LVOTO during surgery might be related to improper operation of the atrialized right ventricle.展开更多
文摘Aim: To study the relationship between Ureaplasma urealyticum (UU) infection and apoptosis of human spermato-genic cells. Methods: Spermatogenic cells were observed under light microscope with Wright-Giemsa staining andby means of terminal deoxynucleotidyl transferase-mediated deoxyuridine triphosphate (dUTP)-biotin nick-end labeling(TUNEL) technique. Results: Apoptotic rate of UU-infected males (15.5 % ± 6.8 % ) was significantly higherthan that of controls (5.2 % ± 2.3 % ). Conclusion: Apoptosis of spermatogenic cells can be caused by UU in-fection, which provides further evidence for UU-induced male infertility. (Asian J Androl 1999 Sep ; 1: 127 - 129)
基金supported by the National Natural Science Foundation of China (No.50874083)the China Postdoctoral Science Foundation (No.201104493)the China International Scientific and Technological Cooperation Projects (No.2010DFA52130)
文摘A novel diffusion couple method was used to investigate the interface diffusion of arsenic into a Nb-Ti microalloyed low carbon steel and its effects on phase transformation at the interface. It is discovered that the content of arsenic has great effect on grain growth and phase transformation at high temperature. When the arsenic content is no more than lwt%, there is no obvious grain growth and no obvious ferrite transitional region formed at the diffusion interface. However, when the arsenic content is no less than 5wt%, the grain grows very rapidly. In addition, the arsenic-enriched ferrite transitional layer forms at the diffusion interface in the hot-rolling process, which results from a slower diffusion rate of arsenic atoms than that of carbon in ferrite.
基金supported by the National Natural Science Foundation of China (No.50874083)the Foundation of Hubei Educational Committee (No.Q20091110)
文摘Auger electron spectroscopy (AES) was used to investigate the grain boundary segregation of arsenic and nitrogen in a kind of microalloyed steel produced by a compact strip production (CSP) technology at 950 to 1100℃, which are similar to the hot working temperature of the steel on a CSP production line. It was discovered that arsenic segregated on grain boundaries when the steel was annealed at 950℃ for 2 h. When the annealing temperature increased to 1100℃, arsenic was also found to have segregated on grain boundaries in the early annealing stage, for instance, within the first 5 min annealing time. However, if the holding time of the steel at this temperature increased to 2 h, arsenic diffused away from grain boundaries into the matrix again. Nitrogen was not found to have segregated on grain boundaries when the steel was annealed at a relatively low temperature, such as 950℃. But when the annealing temperature increased to 1100℃, nitrogen was detected to have segregated at grain boundaries in the steel.
文摘A chaos control strategy for chaotic current-mode boost converter is presented by using inductor current sampled feedback control technique.The quantitative analysis of control mechanism is performed by establishing a discrete alterative map of the controlled system.The stability criterion,feedback gain,and corresponding critical duty ratio are obtained from the eigenvalue of the map.The simulation results verify the t heoretical analysis results of the control strategy.
基金Supported by The Ministry of Science and Technology of China for the National Five-Year Key Projects in Infectious Diseases,No. 2015ZX10004801
文摘BACKGROUND Data that assess maternal and infant outcomes in hepatitis C virus(HCV)-infected mothers are limited.AIM To investigate the frequency of complications and the associated risk factors.METHODS We performed a cohort study to compare pregnancy and fetal outcomes of HCVviremic mothers with those of healthy mothers.Risk factors were analyzed with logistic regression.RESULTS Among 112 consecutive HCV antibody-positive mothers screened,we enrolled 79 viremic mothers.We randomly selected 115 healthy mothers from the birth registry as the control.Compared to healthy mothers,HCV mothers had a significantly higher frequency of anemia[2.6%(3/115)vs 19.0%(15/79),P<0.001]during pregnancy,medical conditions that required caesarian section[27.8%(32/115)vs 48.1%(38/79),P=0.004],and nuchal cords[9.6%(11/115)vs 34.2%(27/79),P<0.001].In addition,the mean neonatal weight in the HCV group was significantly lower(3278.3±462.0 vs 3105.1±459.4 gms;P=0.006),and the mean head circumference was smaller(33.3±0.6 vs 33.1±0.7 cm;P=0.03).In a multivariate model,HCV-infected mothers were more likely to suffer anemia[adjusted odds ratio(OR):18.1,95%confidence interval(CI):4.3-76.6],require caesarian sections(adjusted OR:2.6,95%CI:1.4-4.9),and have nuchal cords(adjusted OR:5.6,95%CI:2.4-13.0).Their neonates were also more likely to have smaller head circumferences(adjusted OR:2.1,95%CI:1.1-4.3)and lower birth weights than the average(≤3250 gms)with an adjusted OR of 2.2(95%CI:1.2-4.0).The vertical transmission rate was 1%in HCV-infected mothers.CONCLUSION Maternal HCV infections may associate with pregnancy and obstetric complications.We demonstrated a previously unreported association between maternal HCV viremia and a smaller neonatal head circumference,suggesting fetal growth restriction.
基金supported by the National Natural Science Foundation of China under Grant No 50677056
文摘A deconpling control strategy of inverter parallel system is proposed based on the equivalent output impedance of single phase voltage source SPWM (sinusoidal pulse width modulation) inverter. The active power and reactive power are calculated in terms of output voltage and current of the inverter, and sent to the other inverters in the parallel system via controller area network (CAN) bus. By calculating and decoupling the circumfluence of the active power and reactive power, the inverters can share load current via the regulation of the reference-signal phase and amplitude. Experimental results of an 110V/2kVA inverter parallel system show the feasibility of the decoupling control strategy.
基金supported by the Funds for International Cooperation and Exchange of the National Natural Science Foundation of China(31210103919)the Fundamental Research Program of the Ministry of Science and Technology,China(2013FY110400)+4 种基金the CAS/SAFEA International Partnership Program for Creative Research Teamsthe National Natural Science Foundation of China(Nos.31370001,31570025,31560011)the National Natural Science Foundation for Young Scientists of China(31500023)the Natural Science Foundation of Yunnan Province(2013FB066)the Youth Innovation Promotion Association,CAS(2016348).
文摘Fungi of the family Boletaceae are of great importance in both ecology and economy.Our previous molecular phylogenetic studies have shown this family to have an extremely high species diversity in China.To further document the Chinese boletes,morphological studies and phylogenetic analyses were conducted including species of Boletaceae from China and other parts of the world.The results indicate that seven subfamily-level major clades and 62 generic clades can be retrieved,52 of which are found in China.Furthermore,100 species(comprising 32 genera)common in China are illustrated and described here in detail.Among them,four genera and 46 species are new to science,and 26 new combinations are proposed.To interpret the species concepts consistently,epitypes for five species are designated based on collections made from or near the type localities.Notes on eight extralimital species are also provided.Among the species reported here,most of the species are known only from East Asia.Only Leccinum scabrum(Bull.)Gray,Porphyrellus porphyrosporus(Fr.&Hok)E.-J.Gilbert and Tylopilus felleus(Bull.)P.Karst.are widely distributed in the Holarctic,and Buchwaldoboletus lignicola(Kallenb.)Pila´t;Strobilomyces strobilaceus(Scop.)Berk.are in Eurasia;while Aureoboletus mirabilis(Murrill)Halling,Harrya chromapes(Frost)Halling et al.,and Sutorius eximius(Peck)Halling et al.are found throughout East Asia-North America based on morphological and molecular phylogenetic evidences.
文摘Background: Recent studies have indicated that an imbalance of gut microbiota is associated with the development of type 1 diabetes mellitus (TI DM) and there is no literature regarding it in Chinese children yet. The aim of this study was to evaluate the alteration of gut microbiota between children with newly diagnosed T 1DM and healthy controls and to determine if gut microbiota could partly explain the etiology of this disease. Methods: A case-control study was carried out with 15 children with T 1 DM and 15 healthy children. The fecal bacteria composition was investigated by high-throughput sequencing of the V3-V4 region of the 16S rDNA gene and analyzed by the estimators of community richness (Chao) indexes. Results: There was a notable lower richness of fecal bacteria in T1DM group than controls (156.53 ± 36.96 vs. 130.0 ± 32.85, P - 0.047). At the genus level, the composition of Blautia was increased in T 1 DM group than control group whereas the composition of Haemophilus, Lachnospira, Dialister, and Acidaminococcus was decreased. In addition, we found that the percentage of Blautia was correlated positively with HbA 1 c (p = 0.40, P - 0.031), the numbers of T1DM autoantibodies (p = 0.42, P = 0.023), and the titers of tyrosine phosphatase autoantibodies (IA-2) (p= 0.82, P = 0.000) in the study. Conclusions: This study showed that gut microbiota was associated with the development of T 1DM by affecting the autoimmunity, and the results suggested a potential therapy for T1DM via modulating the gut microbiota.
文摘Background:The incidence of Ebstein's anomaly is extremely low,and except for the Mayo Clinic,no cardiac center has reported on a sufficient number of patients.The aim of our study was to report the outcomes of Ebstein's anomaly patients treated with tricuspid valvuloplasty (TVP) or tricuspid valve replacement (TVR).Methods:TVP or TV R was performed in 245 patients from July 2006 to April 2016.We reviewed patients' records and contacted patients via outpatient service and over the telephone.Results:The mean follow-up time was 43.6 ± 32.6 months,and 224 (91.4%) patients underwent follow-up.The mean operative age was 31.2 ± 15.7 years.TVR was performed in 23 patients,and TVP was performed in 201 patients.The 30-day mortality rate was 1.3%,and the overall survival rate was 97.9% at 5 and l0 years.The early mortality rate of the TVP group was lower than that of the TVR group (0.5% vs.8.7%,P =0.028),and the overall mortality rate of the TVP group was lower than that of the TVR group,without statistical significance (1.0% vs.8.7%).After propensity score matching,the rates of mortality and New York Heart Association class ≥Ⅲ were lower in the TVP group than those in the TVR group without statistical significance.Seven patients with Type B Wolff-Parkinson-White (WPW) syndrome underwent one-stage surgery,and arrhythmias disappeared.Six patients suffered from episodes of left ventricular outflow tract obstruction (LVOTO) during surgery.Severe LVOTO could be treated with reoperation of the atrialized right ventricle.Conclusions:Ebstein's anomaly patients treated with TVP or TVR can experience optimal outcomes with midterm follow-up.However,TVP should be the first-choice treatment.Optimal outcomes can be obtained from one-stage operation in patients with Type B WPW syndrome.Severe LVOTO during surgery might be related to improper operation of the atrialized right ventricle.