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61.
范春明 《中国组织工程研究与临床康复》2007,11(24):4806-4809
目的:分析胚胎干细胞和胚胎生殖细胞的生物学特性、体外培养条件、周围微环境对其增殖分化的影响,了解胚胎干细胞和胚胎生殖细胞的关系和应用前景。方法:应用计算机检索万方数据库2000/2007有关生殖细胞、胚胎干细胞、胚胎生殖细胞的相关研究文章,检索词:生殖细胞,胚胎干细胞,胚胎生殖细胞,并限定文章语言种类为中文;同时应用计算机检索PUBMED2000/2006相关文章,检索词:Germ Cells,Primordial germ cells,Embryonic stem cells,Embryonic Germ Cells,限定文章语言种类为“English”。对资料进行初审,纳入标准为有关生殖细胞、胚胎干细胞、胚胎生殖细胞的生物学特性、体外培养及生长抑制因子的作用等相关文章,并查找全文。主要选择基础研究类文章,无论有无对照组均纳入。结果:共检索到相关文章59篇,排除比较陈旧的文章,最后纳入38篇进行总结分析。胚胎干细胞与胚胎生殖细胞分别从附置前早期胚胎内细胞团和早期胎儿生殖嵴原始生殖细胞分离克隆出来,均具有自我更新、无限增殖能力及多向分化潜能,在体外培养条件下可保持稳定的二倍体核型,诱导分化后可形成3种胚胎生殖层。饲养层细胞是人胚胎生殖细胞体外培养的必要条件,常用饲养层细胞有鼠STO细胞系、鼠胚胎成纤维细胞,体外生长所需主要细胞因子包括干细胞生长因子、碱性成纤维细胞生长因子和白血病抑制因子,然而只要在培养基中加入鼠成纤维细胞的上清液和碱性成纤维细胞生长因子,胚胎干细胞可在无饲养层的条件下进行体外培养。结论:胚胎干细胞和胚胎生殖细胞具有相似的增殖特性,一定条件下可以分化为包括生殖细胞在内的所有功能细胞,并可相互转变,在胚胎发育、基因治疗、药物筛选、新药开发、生殖医学及人类疾病的移植治疗中具有广泛的应用前景。 相似文献
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65.
Cleusa P Ferri Sandro S Mitsuhiro Marina CM Barros Elisa Chalem Ruth Guinsburg Vikram Patel Martin Prince Ronaldo Laranjeira 《BMC public health》2007,7(1):209
Background
Both violence and depression during pregnancy have been linked to adverse neonatal outcomes, particularly low birth weight. The aim of this study was to investigate the independent and interactive effects of these maternal exposures upon neonatal outcomes among pregnant adolescents in a disadvantaged population from Sao Paulo, Brazil. 相似文献66.
Savas M. Menticoglou MD CM Frank A. Manning MD Ian Morrison MB Chris R. Harman MD 《The Australian & New Zealand journal of obstetrics & gynaecology》1992,32(2):100-103
Because difficult vaginal delivery is more frequent with macrosomic fetuses, some writers recommend routine Caesarean section for the delivery of fetuses greater than or equal to 4,500 g. The purpose of this study was to evaluate the appropriateness of this recommendation. A retrospective review was undertaken to determine how many fetuses born in our hospital weighing greater than or equal to 4,500 g died or were permanently damaged as a consequence of mechanical difficulties at delivery. During a 10-year period, 590 (75%) of 786 cephalic babies weighing greater than or equal to 4,500 g and alive at the start of labour were born vaginally. No baby died or was permanently damaged as a consequence of mechanical difficulties at delivery. Routine Caesarean section for macrosomic fetuses to prevent death or damage from difficult delivery is not warranted by our results. 相似文献
67.
In a double blind study, 40 infants with cows' milk intolerance of various causes were randomised to receive a nutritionally complete formula in which nitrogen was supplied either as whey hydrolysate or amino acids. The median age of infants was 10 weeks (range 36 weeks' gestation to 108 weeks' postnatal age). After a median follow up period of 25 weeks there was no significant difference in dietary intake between the formulas. Twenty four weeks after entry, weight and weight for length improved equally on both formulas. Plasma albumin improved significantly on the hydrolysed whey formula but not in the amino acid group. Both milks were palatable and normal intakes of formula were maintained. Biochemical and haematological indices remained within normal limits. There was no difference in stool frequency and vomiting between the two formulas. Two infants developed a probable allergic colitis while receiving hydrolysed whey. Amino acid formula may have a role in the management of atopic infants with severe cows' milk intolerance who have already reacted to whey or casein hydrolysate formula. 相似文献
68.
The Significance of Mild Squamous Atypia on Cytology 总被引:2,自引:0,他引:2
J. E. Dew FRACOG P. Athanasatos B AppSc CT CM N. F. Hacker MD FRACOG 《The Australian & New Zealand journal of obstetrics & gynaecology》1995,35(4):443-445
Summary: Between January, 1991 and February, 1993 inclusive, 396 Papanicolaou smears were reported to show Mild Squamous Atypia with or without Human Papilloma Virus (MSA ± HPV). All women with MSA ± HPV smears were routinely recalled for colposcopy. To determine the significance of MSA ± HPV on routine smear screening, the records of all patients were reviewed.
Three hundred and thirty-seven women (85.1%) attended the colposcopy clinic and are the subjects analyzed for this report. The remaining 59 (14.9%) failed to attend. Intraepithelial neoplasia was found in 61 patients (18.1%), of whom 27 (8.0%) had a high grade lesion (CIN 2 or 3 or GIN 2). No patient had invasive cancer of the cervix. Only 1 of the 45 pregnant women had a significant lesion.
It is concluded that all asymptomatic women with MSA ± HPV on cervical smear may be managed in accordance with the current NH and MRC recommendations (1) and have a repeat smear in 6 months and colposcopy if the abnormality persists at 12 months. 相似文献
Three hundred and thirty-seven women (85.1%) attended the colposcopy clinic and are the subjects analyzed for this report. The remaining 59 (14.9%) failed to attend. Intraepithelial neoplasia was found in 61 patients (18.1%), of whom 27 (8.0%) had a high grade lesion (CIN 2 or 3 or GIN 2). No patient had invasive cancer of the cervix. Only 1 of the 45 pregnant women had a significant lesion.
It is concluded that all asymptomatic women with MSA ± HPV on cervical smear may be managed in accordance with the current NH and MRC recommendations (1) and have a repeat smear in 6 months and colposcopy if the abnormality persists at 12 months. 相似文献
69.
Several studies have found a significant increase in the prevalence of some personality disorders in the first-degree relatives of patients with schizophrenia; other studies have found subtle neuropsychological deficits in these relatives. However, little is known about the specificity of the personality traits reported or about the relationship between these traits and the neuropsychological deficits. One hundred first-degree relatives of patients with schizophrenia (AS) and 88 first-degree relatives of affective psychotic (APA) patients completed the Eysenck Personality Questionnaire which measures extraversion, neuroticism, psychoticism. They were also administered the National Adult Reading Test (NART), the Trail Making Test (TMT) and a Verbal Fluency Test (VFT). In the AS group, the male relatives scored significantly higher on the psychoticism scale than the male relatives in the APA group. There were no significant differences in personality between female relatives of the 2 patients groups. In the AS group, the NART scores were superior when the psychoticism scores were lower and the TMT performance was better when the extraversion scores were higher. These results seem to indicate some specificity as well as sex differences of the psychoticism dimension. Moreover, the relationship between the personality dimensions and the neuropsychological performance could indicate that psychoticism increases vulnerability to schizophrenia whereas extraversion decreases it. 相似文献
70.
Esther STF Smeulders Jolanda CM van Haastregt Elisabeth FM van Hoef Jacques ThM van Eijk Gertrudis IJM Kempen 《BMC health services research》2006,6(1):91