Objective To introduce the modeling method of pendulum-like modified rat abdominal heart heterotopic transplantation model and evaluate the quality of the model. Methods An operator without transplantation experience performed 15 consecutive models, recorded the time of each step, changes in body weight and modified Stanford scores, and calculated the surgical success rate, postoperative 1-week survival rate and technical success rate. Ultrasound examinations was performed in 1 week postoperatively. Results The times for donor heart acquisition, donor heart processing, recipient preparation and transplantation anastomosis were (14.3±1.4) min, (3.5±0.6) min, (13.6±2.1) min and (38.3±5.2) min respectively. The surgical success rate was 87% (13/15), and the survival rate 1 week after operative was 100% (13/13). The improved Stanford score indicated a technical success rate of 92% (12/13), and the postoperative 1-week ultrasound examination showed that grafts with Stanford scores ≥3 had detectable pulsation and blood flow signals. Conclusions The pendulum-like modified rat abdominal heart heterotopic transplantation improved model further optimizes the operational steps with a high success rate and stable quality, may be chosen as a modeling option for basic research in heart transplantation in the future.

Objective:The study aimed to investigate the factors of pregnancy failures in patients with low ser-um anti-Müllerian hormone(AMH)level after in vitro fertilization(IVF)or intracytoplasmic sperm injection(ICSI).Method:The clinical outcome of 1184 cycles in 931 patients with serum AMH＜1.1 ng/ml undergoing IVF/ICSI at the Department of Reproductive Medicine of West China Second Hospital,Sichuan University between January 1,2020 and December 31,2020,was retrospectively studied.In total,503 patients(525 cycles)underwent embryo transfer,including clinical pregnant group in 193 patients(193 cycles)and clinical non-pregnant group in 310 pa-tients(332 cycles).All of the patients were divided into three different groups according to their chronological age(＜35,35-＜40,40-51 years old)and five different serum AMH levels(＜0.06 ng/ml,0.06-＜0.20 ng/ml,0.20-＜0.50 ng/ml,0.50-＜0.80 ng/ml,0.80-＜1.10 ng/ml),to explore the relationship with IVF pregnancy outcomes.Multivariate Logistic regression analysis was carried out to explore factors affecting pregnancy out-comes afer IVF/ICSI.Results:①Compared with the clinical pregnancy group,the clinical non-pregnant patients were older,AMH level and antral follicle count(AFC)were lower,the number of MII,2PN,available embryos and top quality embryos were also lower,and endometrial thickness at oocyte pickup(OPU)was thinner,and differ-ences above were statistically significant(P＜0.05).②AMH level,AFC,BMI,total Gn and MII number were signifi-cantly different among different age groups(P＜0.05).The clinical pregnancy rate per transplantation cycle,per oocyte pickup cycle and per ovulation induction cycle also had statistically significant differences(P＜0.001),and the pregnancy rate showed a decreasing trend with the increase of age.③There were significant differences in clinical pregnancy rate per transplantation cycle,per oocyte pickup cycle and per ovulation induction cycle among different ranges of low level AMH(P＜0.05).④Multivariable Logistic regression analysis confirmed that the prob-ability of pregnancy in patients with low AMH level after transfering embryo was significantly affected by patients'age(P=0.002).Receiver operating characteristic(ROC)curve showed that the best cut-off value for predicting clinical pregnancy was 35.5 years,the area under the curve(AUC)was 0.634(95%CI 0.586-0.682,P＜0.001).Conclusions:Patients with low AMH level(＜1.1 ng/ml)still have a good chance of pregnancy after IVF/ICSI treatment,and the most notable influencing factor is the patient's chronological age,rather than AMH.When the actual age of patients is less than 35.5 years,the clinical pregnancy outcome after transferring embryo is better e-ven with low AMH level.

Objective:To analyze the genetic characteristics of the complete genome of a strain of human respiratory syncytial virus (HRSV) in Qinghai province in 2024.Methods:A total of 300 samples were collected during 2024 influenza surveillance in Qinghai province sentinel hospitals from patients with fever accompanied by severe respiratory infection symptoms. We used real-time fluorescent quantitative reverse transcription polymerase chain reaction RT-PCR) method to screen out HRSV subtype B (HRSVB) positive specimens, whole genome sequencing was performed on positivespecimens meeting the requirements for the sequencing. After downloading the global representative HRSVB genotypes at GenBank database, sequence alignment was performed, related evolutionary tree was built and the calculation and analyses of genetic distance were done, analyses of HRSVB sequencing of sequence homology of nucleotides, amino acids and amino acid mutation were performed.Results:The first strain in Qinghai, China/qinghai/2024-03 had a complete sequence of 15 140 bp nucleotides, with HRSV′s all structural characteristics, and subtype HRSVA prototype strain Long strains of nucleotide the lowest homology was 80.0%, and subtype HRSVB prototype strain nucleotide homology was above 94.7%. The result indicated that the first strain in Qinghai belonged to HRSVB subtype. Genetic evolution shows China/qinghai/2024-03 and USA/WA-S23450/2021 (OR326803.1) and Germany/2021 (OR795235.1) all belong to a branch, they have the closest relationship. Phylogenetic analysis of G gene showed that the strain belonged to BA9 genotype of HRSVB subtype, and the hypervariable regions of the genome were SH and G genes.Conclusions:In this study, the complete genome sequence of HRSV China/qinghai/2024-03 was obtained for the first time, and the basic molecular structural characteristics were elucidated, which filled the gaps in the gene and amino acid data of HRSV in our province, and also provided a basis for HRSV epidemiology.

The breakage pattern of unit particles during the production of oral solid dosage forms (OSD) is closely related to the quality of intermediate or final products. To accurately characterize the particles and study the evolution law of particle breakage, the Bonding model of the discrete element method (DEM) was used to investigate the breakage patterns of model parameters, particle shape and process conditions (loading mode and loading rate) on the dynamic breakage, force-time curve, breakage rate, maximum breakage size ratio and fracture strength of particles. The results showed that the particle breakage force was positively correlated with normal strength and bonded disk scale, negatively correlated with normal stiffness per unit area and tangential stiffness per unit area, and weakly correlated with tangential strength. The particle breakage rate was negatively correlated with the aspect ratio of the particles, and the maximum breakage size ratio was positively correlated with the aspect ratio of the particles; among the three loading modes, the breakage rate of compression breakage model was the largest, the breakage rate of shear breakage model was the second largest, and the breakage rate of wear breakage model was the smallest; the maximum breakage size ratio was positively correlated with the loading rate, the loading mode and the loading rate had no mutual influence on particle breakage rate, but had mutual influence on the maximum breakage size ratio. The research results will provide a theoretical basis for the shift of OSD from batch manufacturing to advanced manufacturing.

Objective:The study aimed to investigate the factors of pregnancy failures in patients with low ser-um anti-Müllerian hormone(AMH)level after in vitro fertilization(IVF)or intracytoplasmic sperm injection(ICSI).Method:The clinical outcome of 1184 cycles in 931 patients with serum AMH＜1.1 ng/ml undergoing IVF/ICSI at the Department of Reproductive Medicine of West China Second Hospital,Sichuan University between January 1,2020 and December 31,2020,was retrospectively studied.In total,503 patients(525 cycles)underwent embryo transfer,including clinical pregnant group in 193 patients(193 cycles)and clinical non-pregnant group in 310 pa-tients(332 cycles).All of the patients were divided into three different groups according to their chronological age(＜35,35-＜40,40-51 years old)and five different serum AMH levels(＜0.06 ng/ml,0.06-＜0.20 ng/ml,0.20-＜0.50 ng/ml,0.50-＜0.80 ng/ml,0.80-＜1.10 ng/ml),to explore the relationship with IVF pregnancy outcomes.Multivariate Logistic regression analysis was carried out to explore factors affecting pregnancy out-comes afer IVF/ICSI.Results:①Compared with the clinical pregnancy group,the clinical non-pregnant patients were older,AMH level and antral follicle count(AFC)were lower,the number of MII,2PN,available embryos and top quality embryos were also lower,and endometrial thickness at oocyte pickup(OPU)was thinner,and differ-ences above were statistically significant(P＜0.05).②AMH level,AFC,BMI,total Gn and MII number were signifi-cantly different among different age groups(P＜0.05).The clinical pregnancy rate per transplantation cycle,per oocyte pickup cycle and per ovulation induction cycle also had statistically significant differences(P＜0.001),and the pregnancy rate showed a decreasing trend with the increase of age.③There were significant differences in clinical pregnancy rate per transplantation cycle,per oocyte pickup cycle and per ovulation induction cycle among different ranges of low level AMH(P＜0.05).④Multivariable Logistic regression analysis confirmed that the prob-ability of pregnancy in patients with low AMH level after transfering embryo was significantly affected by patients'age(P=0.002).Receiver operating characteristic(ROC)curve showed that the best cut-off value for predicting clinical pregnancy was 35.5 years,the area under the curve(AUC)was 0.634(95%CI 0.586-0.682,P＜0.001).Conclusions:Patients with low AMH level(＜1.1 ng/ml)still have a good chance of pregnancy after IVF/ICSI treatment,and the most notable influencing factor is the patient's chronological age,rather than AMH.When the actual age of patients is less than 35.5 years,the clinical pregnancy outcome after transferring embryo is better e-ven with low AMH level.

Objective:The study aimed to investigate the factors of pregnancy failures in patients with low ser-um anti-Müllerian hormone(AMH)level after in vitro fertilization(IVF)or intracytoplasmic sperm injection(ICSI).Method:The clinical outcome of 1184 cycles in 931 patients with serum AMH＜1.1 ng/ml undergoing IVF/ICSI at the Department of Reproductive Medicine of West China Second Hospital,Sichuan University between January 1,2020 and December 31,2020,was retrospectively studied.In total,503 patients(525 cycles)underwent embryo transfer,including clinical pregnant group in 193 patients(193 cycles)and clinical non-pregnant group in 310 pa-tients(332 cycles).All of the patients were divided into three different groups according to their chronological age(＜35,35-＜40,40-51 years old)and five different serum AMH levels(＜0.06 ng/ml,0.06-＜0.20 ng/ml,0.20-＜0.50 ng/ml,0.50-＜0.80 ng/ml,0.80-＜1.10 ng/ml),to explore the relationship with IVF pregnancy outcomes.Multivariate Logistic regression analysis was carried out to explore factors affecting pregnancy out-comes afer IVF/ICSI.Results:①Compared with the clinical pregnancy group,the clinical non-pregnant patients were older,AMH level and antral follicle count(AFC)were lower,the number of MII,2PN,available embryos and top quality embryos were also lower,and endometrial thickness at oocyte pickup(OPU)was thinner,and differ-ences above were statistically significant(P＜0.05).②AMH level,AFC,BMI,total Gn and MII number were signifi-cantly different among different age groups(P＜0.05).The clinical pregnancy rate per transplantation cycle,per oocyte pickup cycle and per ovulation induction cycle also had statistically significant differences(P＜0.001),and the pregnancy rate showed a decreasing trend with the increase of age.③There were significant differences in clinical pregnancy rate per transplantation cycle,per oocyte pickup cycle and per ovulation induction cycle among different ranges of low level AMH(P＜0.05).④Multivariable Logistic regression analysis confirmed that the prob-ability of pregnancy in patients with low AMH level after transfering embryo was significantly affected by patients'age(P=0.002).Receiver operating characteristic(ROC)curve showed that the best cut-off value for predicting clinical pregnancy was 35.5 years,the area under the curve(AUC)was 0.634(95%CI 0.586-0.682,P＜0.001).Conclusions:Patients with low AMH level(＜1.1 ng/ml)still have a good chance of pregnancy after IVF/ICSI treatment,and the most notable influencing factor is the patient's chronological age,rather than AMH.When the actual age of patients is less than 35.5 years,the clinical pregnancy outcome after transferring embryo is better e-ven with low AMH level.

Objective:The study aimed to investigate the factors of pregnancy failures in patients with low ser-um anti-Müllerian hormone(AMH)level after in vitro fertilization(IVF)or intracytoplasmic sperm injection(ICSI).Method:The clinical outcome of 1184 cycles in 931 patients with serum AMH＜1.1 ng/ml undergoing IVF/ICSI at the Department of Reproductive Medicine of West China Second Hospital,Sichuan University between January 1,2020 and December 31,2020,was retrospectively studied.In total,503 patients(525 cycles)underwent embryo transfer,including clinical pregnant group in 193 patients(193 cycles)and clinical non-pregnant group in 310 pa-tients(332 cycles).All of the patients were divided into three different groups according to their chronological age(＜35,35-＜40,40-51 years old)and five different serum AMH levels(＜0.06 ng/ml,0.06-＜0.20 ng/ml,0.20-＜0.50 ng/ml,0.50-＜0.80 ng/ml,0.80-＜1.10 ng/ml),to explore the relationship with IVF pregnancy outcomes.Multivariate Logistic regression analysis was carried out to explore factors affecting pregnancy out-comes afer IVF/ICSI.Results:①Compared with the clinical pregnancy group,the clinical non-pregnant patients were older,AMH level and antral follicle count(AFC)were lower,the number of MII,2PN,available embryos and top quality embryos were also lower,and endometrial thickness at oocyte pickup(OPU)was thinner,and differ-ences above were statistically significant(P＜0.05).②AMH level,AFC,BMI,total Gn and MII number were signifi-cantly different among different age groups(P＜0.05).The clinical pregnancy rate per transplantation cycle,per oocyte pickup cycle and per ovulation induction cycle also had statistically significant differences(P＜0.001),and the pregnancy rate showed a decreasing trend with the increase of age.③There were significant differences in clinical pregnancy rate per transplantation cycle,per oocyte pickup cycle and per ovulation induction cycle among different ranges of low level AMH(P＜0.05).④Multivariable Logistic regression analysis confirmed that the prob-ability of pregnancy in patients with low AMH level after transfering embryo was significantly affected by patients'age(P=0.002).Receiver operating characteristic(ROC)curve showed that the best cut-off value for predicting clinical pregnancy was 35.5 years,the area under the curve(AUC)was 0.634(95%CI 0.586-0.682,P＜0.001).Conclusions:Patients with low AMH level(＜1.1 ng/ml)still have a good chance of pregnancy after IVF/ICSI treatment,and the most notable influencing factor is the patient's chronological age,rather than AMH.When the actual age of patients is less than 35.5 years,the clinical pregnancy outcome after transferring embryo is better e-ven with low AMH level.

Objective:The study aimed to investigate the factors of pregnancy failures in patients with low ser-um anti-Müllerian hormone(AMH)level after in vitro fertilization(IVF)or intracytoplasmic sperm injection(ICSI).Method:The clinical outcome of 1184 cycles in 931 patients with serum AMH＜1.1 ng/ml undergoing IVF/ICSI at the Department of Reproductive Medicine of West China Second Hospital,Sichuan University between January 1,2020 and December 31,2020,was retrospectively studied.In total,503 patients(525 cycles)underwent embryo transfer,including clinical pregnant group in 193 patients(193 cycles)and clinical non-pregnant group in 310 pa-tients(332 cycles).All of the patients were divided into three different groups according to their chronological age(＜35,35-＜40,40-51 years old)and five different serum AMH levels(＜0.06 ng/ml,0.06-＜0.20 ng/ml,0.20-＜0.50 ng/ml,0.50-＜0.80 ng/ml,0.80-＜1.10 ng/ml),to explore the relationship with IVF pregnancy outcomes.Multivariate Logistic regression analysis was carried out to explore factors affecting pregnancy out-comes afer IVF/ICSI.Results:①Compared with the clinical pregnancy group,the clinical non-pregnant patients were older,AMH level and antral follicle count(AFC)were lower,the number of MII,2PN,available embryos and top quality embryos were also lower,and endometrial thickness at oocyte pickup(OPU)was thinner,and differ-ences above were statistically significant(P＜0.05).②AMH level,AFC,BMI,total Gn and MII number were signifi-cantly different among different age groups(P＜0.05).The clinical pregnancy rate per transplantation cycle,per oocyte pickup cycle and per ovulation induction cycle also had statistically significant differences(P＜0.001),and the pregnancy rate showed a decreasing trend with the increase of age.③There were significant differences in clinical pregnancy rate per transplantation cycle,per oocyte pickup cycle and per ovulation induction cycle among different ranges of low level AMH(P＜0.05).④Multivariable Logistic regression analysis confirmed that the prob-ability of pregnancy in patients with low AMH level after transfering embryo was significantly affected by patients'age(P=0.002).Receiver operating characteristic(ROC)curve showed that the best cut-off value for predicting clinical pregnancy was 35.5 years,the area under the curve(AUC)was 0.634(95%CI 0.586-0.682,P＜0.001).Conclusions:Patients with low AMH level(＜1.1 ng/ml)still have a good chance of pregnancy after IVF/ICSI treatment,and the most notable influencing factor is the patient's chronological age,rather than AMH.When the actual age of patients is less than 35.5 years,the clinical pregnancy outcome after transferring embryo is better e-ven with low AMH level.

Objective:The study aimed to investigate the factors of pregnancy failures in patients with low ser-um anti-Müllerian hormone(AMH)level after in vitro fertilization(IVF)or intracytoplasmic sperm injection(ICSI).Method:The clinical outcome of 1184 cycles in 931 patients with serum AMH＜1.1 ng/ml undergoing IVF/ICSI at the Department of Reproductive Medicine of West China Second Hospital,Sichuan University between January 1,2020 and December 31,2020,was retrospectively studied.In total,503 patients(525 cycles)underwent embryo transfer,including clinical pregnant group in 193 patients(193 cycles)and clinical non-pregnant group in 310 pa-tients(332 cycles).All of the patients were divided into three different groups according to their chronological age(＜35,35-＜40,40-51 years old)and five different serum AMH levels(＜0.06 ng/ml,0.06-＜0.20 ng/ml,0.20-＜0.50 ng/ml,0.50-＜0.80 ng/ml,0.80-＜1.10 ng/ml),to explore the relationship with IVF pregnancy outcomes.Multivariate Logistic regression analysis was carried out to explore factors affecting pregnancy out-comes afer IVF/ICSI.Results:①Compared with the clinical pregnancy group,the clinical non-pregnant patients were older,AMH level and antral follicle count(AFC)were lower,the number of MII,2PN,available embryos and top quality embryos were also lower,and endometrial thickness at oocyte pickup(OPU)was thinner,and differ-ences above were statistically significant(P＜0.05).②AMH level,AFC,BMI,total Gn and MII number were signifi-cantly different among different age groups(P＜0.05).The clinical pregnancy rate per transplantation cycle,per oocyte pickup cycle and per ovulation induction cycle also had statistically significant differences(P＜0.001),and the pregnancy rate showed a decreasing trend with the increase of age.③There were significant differences in clinical pregnancy rate per transplantation cycle,per oocyte pickup cycle and per ovulation induction cycle among different ranges of low level AMH(P＜0.05).④Multivariable Logistic regression analysis confirmed that the prob-ability of pregnancy in patients with low AMH level after transfering embryo was significantly affected by patients'age(P=0.002).Receiver operating characteristic(ROC)curve showed that the best cut-off value for predicting clinical pregnancy was 35.5 years,the area under the curve(AUC)was 0.634(95%CI 0.586-0.682,P＜0.001).Conclusions:Patients with low AMH level(＜1.1 ng/ml)still have a good chance of pregnancy after IVF/ICSI treatment,and the most notable influencing factor is the patient's chronological age,rather than AMH.When the actual age of patients is less than 35.5 years,the clinical pregnancy outcome after transferring embryo is better e-ven with low AMH level.

Objective:The study aimed to investigate the factors of pregnancy failures in patients with low ser-um anti-Müllerian hormone(AMH)level after in vitro fertilization(IVF)or intracytoplasmic sperm injection(ICSI).Method:The clinical outcome of 1184 cycles in 931 patients with serum AMH＜1.1 ng/ml undergoing IVF/ICSI at the Department of Reproductive Medicine of West China Second Hospital,Sichuan University between January 1,2020 and December 31,2020,was retrospectively studied.In total,503 patients(525 cycles)underwent embryo transfer,including clinical pregnant group in 193 patients(193 cycles)and clinical non-pregnant group in 310 pa-tients(332 cycles).All of the patients were divided into three different groups according to their chronological age(＜35,35-＜40,40-51 years old)and five different serum AMH levels(＜0.06 ng/ml,0.06-＜0.20 ng/ml,0.20-＜0.50 ng/ml,0.50-＜0.80 ng/ml,0.80-＜1.10 ng/ml),to explore the relationship with IVF pregnancy outcomes.Multivariate Logistic regression analysis was carried out to explore factors affecting pregnancy out-comes afer IVF/ICSI.Results:①Compared with the clinical pregnancy group,the clinical non-pregnant patients were older,AMH level and antral follicle count(AFC)were lower,the number of MII,2PN,available embryos and top quality embryos were also lower,and endometrial thickness at oocyte pickup(OPU)was thinner,and differ-ences above were statistically significant(P＜0.05).②AMH level,AFC,BMI,total Gn and MII number were signifi-cantly different among different age groups(P＜0.05).The clinical pregnancy rate per transplantation cycle,per oocyte pickup cycle and per ovulation induction cycle also had statistically significant differences(P＜0.001),and the pregnancy rate showed a decreasing trend with the increase of age.③There were significant differences in clinical pregnancy rate per transplantation cycle,per oocyte pickup cycle and per ovulation induction cycle among different ranges of low level AMH(P＜0.05).④Multivariable Logistic regression analysis confirmed that the prob-ability of pregnancy in patients with low AMH level after transfering embryo was significantly affected by patients'age(P=0.002).Receiver operating characteristic(ROC)curve showed that the best cut-off value for predicting clinical pregnancy was 35.5 years,the area under the curve(AUC)was 0.634(95%CI 0.586-0.682,P＜0.001).Conclusions:Patients with low AMH level(＜1.1 ng/ml)still have a good chance of pregnancy after IVF/ICSI treatment,and the most notable influencing factor is the patient's chronological age,rather than AMH.When the actual age of patients is less than 35.5 years,the clinical pregnancy outcome after transferring embryo is better e-ven with low AMH level.