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31.
A familial lymphoproliferative disorder presented in three male siblings with primary pulmonary involvement manifested as either lymphoid interstitial pneumonia or an angiodestructive polymorphous infiltrate morphologically resembling lymphomatoid granulomatosis. The polymorphous infiltrate consisted chiefly of mature T-cells with a few B-cells and plasma cells, and gene rearrangement studies failed to show clonality. Epstein-Barr virus, frequently associated with proliferative lesions in males in the X-linked lymphoproliferative syndrome, was not demonstrated in any of the pulmonary lesions. An HLA haplotype shared among the affected siblings was A1, B8, DR4. The unusual clinical presentation plus the lack of involvement by EBV in the pulmonary lesions suggests that this is a previously undescribed familial lymphoproliferative disorder.  相似文献   
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Studies to detect ultrastructural changes in testicular tissues after a fifteen-minute exposure to ultrasonic waves were done in 10 men undergoing bilateral orchiectomies for prostatic carcinoma. Examination of Sertoli cells and germ cells in different stages of differentiation failed to reveal significant differences between exposed and control testes.  相似文献   
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Three muscle biopsies were performed in 53 overt type 2 diabetics over a period of approximately 2 years. At baseline, 21 (40%) had an increased capillary basement membrane width in muscle. Thirty-five patients received glipizide and 18 received placebo. In the patients receiving placebo, the mean of the muscle capillary basement membrane width increased from 158.7 +/- 11.5 nm (SEM) to 170.9 +/- 14.7 nm (P = NS), but in those receiving glipizide the value decreased from 192.9 +/- 13.2 nm to 161.0 +/- 10.2 nm (P = 0.02). Plasma glucose and glycosylated hemoglobin A1 decreased significantly (P less than 0.001) after 2 years in patients receiving glipizide. In 15, mean glycosylated hemoglobin A1 reached a normal range, and mean basement membrane width decreased to a level close to that found in subjects without diabetes (P = NS). These findings are consistent with the hypothesis that effective response to oral medication can decrease the basement membrane thickening, suggesting that diabetic microangiopathy is not necessarily progressive.  相似文献   
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In this study, we have used time-lapse video cinematography to study fertilization in 50 human oocytes that had undergone intracytoplasmic sperm injection (ICSI). Time-lapse recording commenced shortly after ICSI and proceeded for 17-20 h. Oocytes were cultured in an environmental chamber which was maintained under standard culture conditions. Overall, 38 oocytes (76%) were fertilized normally, and the fertilization rate and embryo quality were not significantly different from 487 sibling oocytes cultured in a conventional incubator. Normal fertilization followed a defined course of events, although the timing of these events varied markedly between oocytes. In 35 of the 38 fertilized oocytes (92%), there were circular waves of granulation within the ooplasm which had a periodicity of 20-53 min. The sperm head decondensed during this granulation phase. The second polar body was then extruded, and this was followed by the central formation of the male pronucleus. The female pronucleus formed in the cytoplasm adjacent to the second polar body at the same time as, or slightly after, the male pronucleus, and was subsequently drawn towards the male pronucleus until the two abutted. Both pronuclei then increased in size, the nucleoli moved around within the pronuclei and some nucleoli coalesced. During pronuclear growth, the organelles contracted from the cortex towards the centre of the oocyte, leaving a clear cortical zone. The oocyte decreased in diameter from 112 to 106 microm (P < 0.0001) during the course of the observation period. The female pronucleus was significantly smaller in diameter than the male pronucleus (24.1 and 22.4 microm respectively, P = 0.008) and contained fewer nucleoli (4.2 and 7.0 respectively, P < 0.0001). After time-lapse recording, oocytes were cultured for 48 h prior to embryo transfer or cryopreservation. Embryo quality was related to fertilization events and periodicity of the cytoplasmic wave, and it was found that good quality embryos arose from oocytes that had more uniform timing from injection to pronuclear abuttal and tended to have a longer cytoplasmic wave. In conclusion, we have shown that time-lapse video cinematography is an excellent tool for studying fertilization and early embryo development, and have demonstrated that human fertilization comprises numerous complex dynamic events.   相似文献   
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As more mutations are identified in genes of known sequence, there is a crucial need in the areas of medical genetics and genome analysis for rapid, accurate and cost-effective methods of mutation detection. We have developed a multiplex allele-specific diagnostic assay (MASDA) for analysis of large numbers of samples (> 500) simultaneously for a large number of known mutations (> 100) in a single assay. MASDA utilizes oligonucleotide hybridization to interrogate DNA sequences. Multiplex DNA samples are immobilized on a solid support and a single hybridization is performed with a pool of allele-specific oligonucleotide (ASO) probes. Any probes complementary to specific mutations present in a given sample are in effect affinity purified from the pool by the target DNA. Sequence-specific band patterns (fingerprints), generated by chemical or enzymatic sequencing of the bound ASO(s), easily identify the specific mutation(s). Using this design, in a single diagnostic assay, we tested samples for 66 cystic fibrosis (CF) mutations, 14 beta-thalassemia mutations, two sickle cell anemia (SCA) mutations, three Tay-Sachs mutations, eight Gaucher mutations, four mutations in Canavan disease, four mutations in Fanconi anemia, and five mutations in BRCA1. Each mutation was correctly identified. Finally, in a blinded study of 106 of these mutations in > 500 patients, all mutations were properly identified. There were no false positives or false negatives. The MASDA assay is capable of detecting point mutations as well as small insertion or deletion mutations. This technology is amenable to automation and is suitable for immediate utilization for high-throughput genetic diagnostics in clinical and research laboratories.   相似文献   
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