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In a large collaborative screening project, 370 men with idiopathic azoospermia or severe oligozoospermia were analysed for deletions of 76 DNA loci in Yq11. In 12 individuals, we observed de novo microdeletions involving several DNA loci, while an additional patient had an inherited deletion. They were mapped to three different subregions in Yq11. One subregion coincides to the AZF region defined recently in distal Yq11. The second and third subregion were mapped proximal to it, in proximal and middle Yq11, respectively. The different deletions observed were not overlapping but the extension of the deleted Y DNA in each subregion was similar in each patient analysed. In testis tissue sections, disruption of spermatogenesis was shown to be at the same phase when the microdeletion occurred in the same Yq11 subregion but at a different phase when the microdeletion occurred in a different Yq11 subregion. Therefore, we propose the presence of not one but three spermatogenesis loci in Yq11 and that each locus is active during a different phase of male germ cell development. As the most severe phenotype after deletion of each locus is azoospermia, we designated them as: AZFa, AZFb and AZFc. Their probable phase of function in human spermatogenesis and candidate genes involved will be discussed.   相似文献   
63.
Fifty-eight migraineurs were. studied by intermediate frequency steady-state visual evoked potentials (SSVEPs) during headache-free periods. Sex, age, age of onset of migraine, duration of illness, type of migraine, side of pain, sleep .wake disorders, and frequency of migraine attacks did not correlate with any SSVEP abnormalities. On the other hand, visual responsiveness was significantly increased in subjects with family history of migraine, and in those with autonomic symptoms. Our results may indicate that a genetic predisposition to migraine underlies the observed abnormal visual response in migraineurs.  相似文献   
64.
Hall  FM; Storella  JM; Silverstone  DZ; Wyshak  G 《Radiology》1988,167(2):353-358
Carcinoma was found in 30% (119 of 400) of biopsy specimens obtained for mammographically suspicious but nonpalpable findings. The authors reviewed the mammograms of these 400 cases without knowledge of the biopsy results and placed each examination into one of four groups based on their suspicion for carcinoma: minimal (n = 82), slight (n = 91), moderate (n = 174), and high (n = 53). In 127 cases, mammograms showed either minimally suspicious calcifications (n = 33) or minimally (n = 49) or slightly (n = 45) suspicious masses. A 4.7% (six of 127) rate of carcinoma was found in these groups; five of the six cancers were in situ. Had follow-up mammography been done rather than biopsy for these 127 less suspicious lesions, it is probable that the delay in diagnosis would not have altered overall prognosis. In the remaining 273 patients, the positive predictive value of mammography for carcinoma would have risen from 30% (119 of 400) to 41% (113 of 273). The authors conclude that in the management of suspicious nonpalpable mammographic findings, the rate of carcinoma for lesions at biopsy can approximate 40%. This is almost double the rate of most published series.  相似文献   
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5种解热镇痛药的胶束电动毛细管色谱分离研究   总被引:1,自引:0,他引:1  
陈勇  韩凤梅  袁倬斌 《药学学报》1996,31(8):637-640
报告了5种解热镇痛药——安替比林、4-氨基安替比林、安基比林、安乃近和保泰松的胶束电动毛细管色谱分离、紫外吸收检测法。研究了pH值、有机改性剂(甲醇)和十二烷基硫酸钠(SDS)浓度对分离的影响。在40mmol·L-1SDS—25mmol·L-1硼砂—15%甲醇(pH10.5)电泳介质中电泳,上述5组分可达基线分离。迁移时间批内和批间的RSD值分别小于1.3%和2.1%(n=5)。分离的理论塔板数在1.83×104~4.15×104之间。  相似文献   
67.

Objective

TAP is a regional anaesthetic technique where local anaesthesic (LA) is injected between the internal oblique and the transversus abdominis muscles in order to block intercostal nerves. The technique originally described, is based on the identification of the lumbar triangle of Petit as the area where to insert the needle before the LA injection. We performed a study to determine, using ultrasonography, the actual location of the LA when TAP block was performed using landmark-based technique.

Study design

Prospective and observational study.

Methods

Fifty-two patients scheduled for ileostomy closure surgery under general anaesthesia received a TAP block (20 mL 0.75% ropivacaine) based on standard anatomical landmarks technique. Ultrasonography was used immediately after the block to determine the LA placement. Failed blocks were considered when the patient required intravenous morphine in the immediate postoperative period for pain localised at the operative site.

Results

LA solution was injected in the right place in 14 cases out of 52. Only one of these patient received morphine in the postoperative period. In the remaining 38 blocks, the LA was administered in adjacent anatomical structures and 25 failed. Two injections in the peritoneum were observed.

Conclusion

The localization of LA after the TAP block being performed by landmark-based techniques is highly variable. In the majority of patients, the LA was injected in adjacent anatomical structures with unpredictable block results. This may promote the use of ultrasound-guided technique to perform the TAP block.  相似文献   
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