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An RNA-binding motif (RBM) gene family has been identified on the human Y chromosome that maps to the same deletion interval as the 'azoospermia factor' (AZF). We have identified the homologous gene family (Rbm) on the mouse Y with a view to investigating the proposal that this gene family plays a role in spermatogenesis. At least 25 and probably >50 copies of Rbm are present on the mouse Y chromosome short arm located between Sry and the centromere. As in the human, a role in spermatogenesis is indicated by a germ cell-specific pattern of expression in the testis, but there are distinct differences in the pattern of expression between the two species. Mice carrying the deletion Yd1, that maps to the proximal Y short arm, are female due to a position effect resulting in non-expression of Sry ; sex-reversing such mice with an Sry transgene produces males with a high incidence of abnormal sperm, making this the third deletion interval on the mouse Y that affects some aspect of spermatogenesis. Most of the copies of Rbm map to this deletion interval, and the Yd1males have markedly reduced Rbm expression, suggesting that RBM deficiency may be responsible for, or contribute to, the abnormal sperm development. In man, deletion of the functional copies of RBM is associated with meiotic arrest rather than sperm anomalies; however, the different effects of deletion are consistent with the differences in expression between the two species.   相似文献   
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A 9.7 kb segment encompassing exons 7-10 of the adrenoleukodystrophy (ALD) locus of the X chromosome has duplicated to specific locations near the pericentromeric regions of human chromosomes 2p11,10p11, 16p11 and 22q11. Comparative sequence analysis reveals 92-96% nucleotide identity, indicating that the autosomal ALD paralogs arose relatively recently during the course of higher primate evolution (5-10 million years ago). Analysis of sequences flanking the duplication region identifies the presence of an unusual GCTTTTTGC repeat which may be a sequence-specific integration site for the process of pericentromeric- directed transposition. The breakpoint sequence and phylogenetic analysis predict a two-step transposition model, in which a duplication from Xq28 to pericentromeric 2p11 occurred once, followed by a rapid distribution of a larger duplicon cassette among the pericentromeric regions. In addition to facilitating more effective mutation detection among ALD patients, these findings provide further insight into the molecular basis underlying a pericentromeric-directed mechanism for non- homologous interchromosomal exchange.   相似文献   
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In-vitro fertilization patients (n = 15) at risk of ovarian hyperstimulation syndrome (OHSS) (oestradiol > or =4500 pg/ml on the day of human chorionic gonadotrophin administration and 25 or more follicles of intermediate or large size) underwent aspiration of all follicles and cryopreservation of all fertilized oocytes at the pronuclear stage. Patients were monitored for up to 2 weeks post- retrieval. Subsequent transfer of cryopreserved-thawed embryos was performed in programmed cycles using exogenous oestrogen and progesterone for endometrial preparation. Two patients (13%) developed OHSS necessitating hospitalization and vaginal aspiration of ascitic fluid. Two other patients (13%) developed moderate OHSS requiring ascitic fluid vaginal aspiration in the office setting, with dramatic improvement of the condition. Subsequent transfer of cryopreserved- thawed embryos yielded a clinical pregnancy rate of 58% per transfer and ongoing or delivery rates of 42 and 67% per transfer and per patient respectively. By eliminating pregnancy potential with cryopreservation of all prezygotes and examining the pregnancy potential with subsequent cryopreserved-thawed transfers, it is concluded that OHSS is reduced, but not eliminated for patients at risk. Subsequent transfer of cryopreserved-thawed prezygotes in a programmed cycle with exogenous steroids yields an excellent pregnancy rate.   相似文献   
15.
癌基因c-erbB-2在膀胱移行细胞癌中的扩增   总被引:2,自引:1,他引:1  
赵致广  张莉莉 《医学争鸣》2000,21(4):482-482
0 引言 为探讨癌基因 c- erb B- 2的扩增与膀胱移行细胞癌(TCC)的关系 ,我们以斑点杂交的方法对 40例膀胱 TCC标本中 c- erb B- 2的扩增情况进行了检测 ,以期明确 c- erb B- 2扩增与膀胱 TCC病理分级及患者预后的关系 .1 材料和方法  40例膀胱 TCC患者术后石蜡包埋标本 ,随访 5~ 10 a. 11例正常膀胱粘膜石蜡标本作为对照 . c- erb B-c DNA p CER2 0 4质粒由东京大学提供 ,Bothringer缺口平移 DNA标记试剂盒及 32 P标记 d CTP购于北京福瑞公司 .所有石蜡标本经脱蜡及蛋白酶消化 ,以酚 /氯仿抽提 DNA,乙醇沉淀 .每份样品取…  相似文献   
16.
Purpose To characterize and predict cycles generating slowcleaving embryos in in vitro fertilization, 86 cycles were retrospectively divided into two groups (slow, n=41, and fast, n=45 according to whether the number of blastomeres per embryo on day 3 was or > than the mean of the distribution, respectively.Results Cycles generating slowcleaving embryos were treated with luteinizing hormonereleasing hormone agonist before ovarian stimulation for a shorter period (12.1±0.5 versus 15.6±1.1 days; P0.01) and had higher immaturity grade of oocyte-corona-cumulus complexes which resulted in embryos (1.6±0.1 vs 1.3±0.1; P0.05) when compared to cycles producing fastcleaving embryos. Both variables entered in a logistic regression model applied in order to predict the probability of a cycle generating slowcleaving embryos (goodness-of-fit chisquare=180.0, degrees of freedom (df)=80, P=0.4786. This model predicted correctly 86.7% (13 of 15) of cycles generating slowcleaving embryos and 83.3% (10 of 12) of cycles producing fastcleaving embryos when the estimated probability of a cycle producing slowcleaving embryos was 0.7 or 0.3, respectively.Conclusion Shorter treatment with hormone-releasing hormone agonist before ovarian stimulation and higher immaturity grade of oocyte-corona-cumulus complexes which result in embryos are predictive characteristics of in vitro fertilization cycles generating slow-cleaving embryos.  相似文献   
17.
Sadowski E  Demos TC  Lomasney LM  Rabin SI 《Orthopedics》1999,22(3):372, 363-372, 366
An ankle radiographic series frequently is obtained when a patient presents with an acute ankle and foot injury. Although many fractures are confined to the ankle and are readily apparent, fractures of the foot can mimic ankle injuries. It is important to differentiate these fractures of the foot from the more common ankle sprain. Most ankle sprains are treated with ice, compression, and elevation, followed by range-of-motion exercises and progressive weight bearing as tolerated. When foot fractures are not identified, however, lack of appropriate treatment can result in late complications. Concentration on key areas as described here will reduce the incidence of missed fractures of the foot in these patients.  相似文献   
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19.
银杏叶提取物改善反复脑缺血再灌注小鼠血液流变学的作用   总被引:34,自引:0,他引:34  
目的:研究银杏叶提取物(EGB)改善反复脑缺血再灌注小鼠血液流这的作用。方法:采用反复脑缺血再注模型鼠,应用毛细管微量热沉法和毛细管微量法分别检测血纤维蛋白原含量和红细胞压积数值,并将结果输入全自动血液流变仪得出血浆粘度、血液粘度、血细胞聚集系数,血栓形成系数及微循环滞留时间(MST)。结果:EBG25 ̄100mg/kg均可不同程度地降低Fib、HCT、降低ηb、ηp、ηh,缩小VAL及TWEL,  相似文献   
20.
邹立  陈声池 《吉林医学》2014,(35):7786-7788
目的:比较甲地孕酮联合NP方案和单用NP方案化疗对晚期非小细胞肺癌生活质量的影响,评价甲地孕酮的临床疗效。方法:将60例晚期非小细胞肺癌患者随机分为治疗组与对照组。治疗组30例,于化疗前2天口服甲地孕酮160 mg,2次/d,同时予NP方案化疗。对照组30例仅接受NP方案化疗。于化疗4周期后评价患者的食欲、体重变化、KPS评分及不良反应。结果:经过4个周期后治疗组食欲、体重、KPS评分改善情况与对照组相比差异有统计学意义(P<0.05)。治疗组主要不良反应为高血压、便秘、血糖升高、皮疹、阴道流血、踝部水肿等反应,经对症处理后可缓解。结论:甲地孕酮可改善晚期非小细胞肺癌患者的生活质量,减轻其不良反应,不良反应可耐受。  相似文献   
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