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51.
We report two clinical pregnancies occurring after intracytoplasmic sperm injection (ICSI) using cryopreserved spermatozoa obtained from testicular biopsy, made in two different infertility situations in our clinic. The first patient showed a secretory azoospermia associated with elevated serum follicular stimulating hormone (FSH) level and spermiogenesis maturation arrest. The second patient was affected by azoospermia resulting from bilateral epididymal obstruction. Spermatozoa present in the wet preparation of testicular biopsy made on the day of scrotal exploration were cryopreserved within the testicular tissue for both men. Intracytoplasmic injections were performed at a later date, using spermatozoa prepared from frozen-thawed tissues. In each case, three embryos were obtained and transferred in utero. The transfers resulted in a twin pregnancy for the first case, and in a singleton pregnancy for the second. Living foetuses were seen in the ultrasound scan at the 7th week and both pregnancies are proceeding to date beyond 30 weeks without complications.   相似文献   
52.
Donor insemination (DI) using cryopreserved semen commenced at The Royal Women's Hospital in 1976. Over the next 15 years we performed 5953 treatment cycles to achieve 816 pregnancies (13.7% per cycle) and 706 live births. In-vitro fertilization (IVF) using donor spermatozoa commenced in 1986. Over the next 5 years we performed 303 treatment cycles for 185 couples. Including subsequent transfer of cryopreserved embryos, a total of 33% of couples achieved a successful pregnancy by IVF. Statistical analysis indicated that, for DI pregnancies, the most important semen variable was the percentage post-thaw motility, whilst for normal fertilization in IVF it was the pre-freeze motility. These results may be explained by the compensatory effects of post-thaw processing of spermatozoa for IVF, but not for DI in our clinic.   相似文献   
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康继超  魏树礼 《药学学报》1997,32(7):536-541
为制备能用于清除骨髓中癌细胞的磁性微球,首先合成了单分散、大粒径的多孔聚苯乙烯交联微球,借助微球多孔结构对其进行磁化。探讨了影响磁化效果的主要因素。为使其与单抗连接紧密,在微球表面聚合了一层聚丙烯醛膜,使其表面带上易与单抗反应的醛基。同时测定了所制微球的磁响应性。X-射线衍射证明磁性物质为γ-Fe2O3。  相似文献   
55.

Background  

Cancer metastasis contributes significantly to cancer mortality and is facilitated by lymphangiogenesis and angiogenesis. A new splicing variant, endogenous soluble vascular endothelial growth factor receptor-2 (esVEGFR-2) that we recently identified is an endogenous selective inhibitor of lymphangiogenesis. To evaluate the antimetastatic potential of esVEGFR-2, gene therapy with vector expressing esVEGFR-2 (pesVEGFR-2) or endostatin (pEndo) as a positive control was conducted on murine metastatic mammary cancer.  相似文献   
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Dellagi  K; Brouet  JC; Schenmetzler  C; Praloran  V 《Blood》1981,57(1):189-191
Immunologic studies performed in a case of autoimmune chronic hemolytic anemia with low titer cold agglutinins (1/16) demonstrated that the cold agglutinins corresponded to monoclonal IgG with anti-Pr specificity. This antibody had a large thermal amplitude, being active at 37 degrees C. These unusual characteristics may define a distinct subset of chronic cold agglutinin disease.  相似文献   
59.
Objectives This follow-up study was planned to establish the frequency with which women miss their contraceptive pill, and to observe their behavior when they forget it. In those women who changed from a continuous cycle to an interrupted type of cycle, or vice versa, the study also aimed to evaluate the impact of this change on the pattern of omission of pills. Methods The longitudinal, prospective cohort study included healthy women of child-bearing age for whom a change of pill was being prescribed by their gynecologist. Data were recorded during the 6 months preceding inclusion in the study, and for the 6 months of follow-up; the women were asked to complete a diary in which they recorded the number and exact times of pill omission, and their behavior at each omission. Results A total of 617 gynecologists included 3316 women into the study; of these, a group of 2418 (73%) revisited the same gynecologist at follow-up. The groups who either visited the same or a different gynecologist were similar with respect to age, oral contraception type, omission type and frequency. A large non-compliance rate and women's difficulties in maintaining safe contraception after missing a pill were observed in the group with follow-up. Women were never risk-free when they missed a pill; they turned to numerous sources for discordant or conflicting information; 15% of 'not-forgetting' women at the pre-inclusion cycle recorded at least one omission at the last cycle of the 6-month follow-up period. Omission fluctuations during the observational period make it difficult to designate 'forgetful' or 'non-forgetful' classes of women. Administration of the pill in a continuous cycle, and probably 'study' and 'auto-questionnaire' effects, contributed to an improvement in compliance. In the group taking the continuous cycle pill, the omission number slightly decreased, particularly on the first day and week of the cycle, irrespective of the initial cycle type. Conclusions The importance of the phenomenon of non-compliance rate is confirmed as well as women's difficulties in knowing how to maintain contraceptive safety. The continuous cycle regimen is likely to improve women's compliance during the critical period of the cycle.  相似文献   
60.
Magnetic resonance (MR) imaging with a whole-body imager was performed in 10 fresh, unfixed whole human brains selected randomly from cadavers. All subjects were neurologically intact before death. T2 time constants were measured within the caudate nucleus, putamen, globus pallidus, cortical gray matter, subcortical white matter, and optic radiation. These regions were then excised, and T2 values were measured again with a 1.5-T MR spectrometer. Quantitative assays of iron, ferritin, and protein from these areas were then performed. Iron concentration varied significantly among brain regions, whereas ferritin and protein concentrations were constant among brain regions and among individuals. Neither iron nor ferritin concentration showed any consistent correlation with T2 values. Histologic examination of brain micro-sections with iron- and ferritin-specific stains of demonstrated poor correlation with biochemical assays of ferritin and iron concentrations. Results indicate that T2 values correlate poorly with iron and ferritin concentrations found in neurologically intact brains.  相似文献   
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