2012年以来,MOOC受到了国内外学者的广泛关注,涌现出大量的研究成果。为了深入分析国内外MOOC研究的整体情况以及研究重点的异同,本研究从国内外认可度较高的数据库Web of Science和CSSCI收集MOOC研究的相关文献,并采用CitespaceⅢ可视...2012年以来,MOOC受到了国内外学者的广泛关注,涌现出大量的研究成果。为了深入分析国内外MOOC研究的整体情况以及研究重点的异同,本研究从国内外认可度较高的数据库Web of Science和CSSCI收集MOOC研究的相关文献,并采用CitespaceⅢ可视化软件生成科学知识图谱,进行统计和可视化分析。着重讨论了国内外MOOC研究的发文量、研究热点、知识基础及前沿3个方面的异同,以期为我国MOOC的进一步发展提供参考。展开更多
The pathogenesis of autoimmune hepatitis (AIH) is complex. However,it is believed that a susceptible individual,owing to his genetic background,sex and age,can develop the disease following exposure to an environmenta...The pathogenesis of autoimmune hepatitis (AIH) is complex. However,it is believed that a susceptible individual,owing to his genetic background,sex and age,can develop the disease following exposure to an environmental trigger. Autoimmune hepatitis does not follow a Mendelian pattern of inheritance; hence no single causative genetic locus has been identified. However,several genes,inside and outside the HLA locus,have been linked to an increased susceptibility to AIH. Epidemiological evidence also suggests that the sex and age of the patient plays a role in AIH pathogenesis as the disease onset occurs mainly in the two first decades of life and a higher disease incidence is observed in females. No environmental trigger has been identified,but several have been proposed,mainly viruses and xenobiotics. This article aims at reviewing the current knowledge on susceptibility factors leading to AIH and putative triggers,emphasizing fundamental mechanisms responsible for the break of liver immunological tolerance.展开更多
This is a retrospective,observational study to evaluate the effect of maternal age on the outcomes of in vitro fertilization and embryo transfer(IVF-ET).11830 IVF-ET cycles from 10268 women were included.Four groups o...This is a retrospective,observational study to evaluate the effect of maternal age on the outcomes of in vitro fertilization and embryo transfer(IVF-ET).11830 IVF-ET cycles from 10268 women were included.Four groups of different maternal age periods were compared.The groups were 21 30 years old group(4549 cycles),31-35 years old group(4424 cycles),36-40 years old group(2429 cycles),and over 40 years old group(428 cycles).The mean starting dose of Gn and mean total dose of Gn in each cycle were significantly higher(P<0.01),while the mean retrieved oocyte number was significantly lower(P<0.01) in groups of higher maternal age period than those in each of the lower groups.The biochemical pregnancy rate and the clinical pregnancy rate were significantly lower(P<0.01),while the miscarriage rate was significantly higher(P<0.01) in groups of higher maternal age period than those in the lower groups.No difference was found in two-pronuclear zygotes(2PN) rate and good quality embryo rate among different groups.Birth defect rate was also comparable in the born babies in different groups.In the group with patients' age over 40 years old,the pregnancy rate was 26.87%,the clinical pregnancy rate was 19.39%,while the miscarriage rate after clinical pregnancy was 36.14%.To draw the conclusion,patients with higher maternal age had worse IVF outcomes.In women of fertile age,patients between 20 and 30 years old have the best IVF outcomes.Patients over 40 years old have poor IVF outcome and high miscarriage rate,which suggested the necessity of preimplantation genetic screening(PGS).展开更多
文摘2012年以来,MOOC受到了国内外学者的广泛关注,涌现出大量的研究成果。为了深入分析国内外MOOC研究的整体情况以及研究重点的异同,本研究从国内外认可度较高的数据库Web of Science和CSSCI收集MOOC研究的相关文献,并采用CitespaceⅢ可视化软件生成科学知识图谱,进行统计和可视化分析。着重讨论了国内外MOOC研究的发文量、研究热点、知识基础及前沿3个方面的异同,以期为我国MOOC的进一步发展提供参考。
文摘The pathogenesis of autoimmune hepatitis (AIH) is complex. However,it is believed that a susceptible individual,owing to his genetic background,sex and age,can develop the disease following exposure to an environmental trigger. Autoimmune hepatitis does not follow a Mendelian pattern of inheritance; hence no single causative genetic locus has been identified. However,several genes,inside and outside the HLA locus,have been linked to an increased susceptibility to AIH. Epidemiological evidence also suggests that the sex and age of the patient plays a role in AIH pathogenesis as the disease onset occurs mainly in the two first decades of life and a higher disease incidence is observed in females. No environmental trigger has been identified,but several have been proposed,mainly viruses and xenobiotics. This article aims at reviewing the current knowledge on susceptibility factors leading to AIH and putative triggers,emphasizing fundamental mechanisms responsible for the break of liver immunological tolerance.
文摘This is a retrospective,observational study to evaluate the effect of maternal age on the outcomes of in vitro fertilization and embryo transfer(IVF-ET).11830 IVF-ET cycles from 10268 women were included.Four groups of different maternal age periods were compared.The groups were 21 30 years old group(4549 cycles),31-35 years old group(4424 cycles),36-40 years old group(2429 cycles),and over 40 years old group(428 cycles).The mean starting dose of Gn and mean total dose of Gn in each cycle were significantly higher(P<0.01),while the mean retrieved oocyte number was significantly lower(P<0.01) in groups of higher maternal age period than those in each of the lower groups.The biochemical pregnancy rate and the clinical pregnancy rate were significantly lower(P<0.01),while the miscarriage rate was significantly higher(P<0.01) in groups of higher maternal age period than those in the lower groups.No difference was found in two-pronuclear zygotes(2PN) rate and good quality embryo rate among different groups.Birth defect rate was also comparable in the born babies in different groups.In the group with patients' age over 40 years old,the pregnancy rate was 26.87%,the clinical pregnancy rate was 19.39%,while the miscarriage rate after clinical pregnancy was 36.14%.To draw the conclusion,patients with higher maternal age had worse IVF outcomes.In women of fertile age,patients between 20 and 30 years old have the best IVF outcomes.Patients over 40 years old have poor IVF outcome and high miscarriage rate,which suggested the necessity of preimplantation genetic screening(PGS).
