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101.
Obstruction of the small intestine: accuracy and role of CT in diagnosis 总被引:17,自引:0,他引:17
Maglinte DD; Gage SN; Harmon BH; Kelvin FM; Hage JP; Chua GT; Ng AC; Graffis RF; Chernish SM 《Radiology》1993,188(1):61
102.
我们成功地建立了一个新的层析等电点聚焦的三步程序.细菌培养液首先以CG-50吸附,洗脱出的粗毒素溶液在PBE_(94)柱上进行层析等电点聚焦.分别用5mMTris-Base pH9.4和Buffalyte_(8-4) pH5.4缓冲液洗脱,出现多个洗脱峰,即刻测定pH值.收集pH6.8~7.1的洗脱液,混合、浓缩,最后通过Sephacryl s-200过滤,以0.05M PBS pH6.8洗脱,出现3个峰,毒素在第1峰.毒素纯度为98%,回收率89%,p17.6,MW28500,SDS-PAGE上1条带.以~(125)I标记SED作探针的电泳转移和放射自显影均证明了提纯SED的免疫学特异性.免疫扩散试验,即使200μg/ml SED与不产毒素的FRI-184抗血清,也未有可见沉淀线. 相似文献
103.
104.
Primary thoracic sarcomas. 总被引:8,自引:0,他引:8
Gregory W Gladish Bradley M Sabloff Reginald F Munden Mylene T Truong Jeremy J Erasmus Marvin H Chasen 《Radiographics》2002,22(3):621-637
Primary sarcomas of the thorax are rare. The diagnosis is established only after sarcomalike primary lung malignancies and metastatic disease have been excluded. Primary sarcomas of the thorax are classified according to their histologic features and constitute a large group of tumors that occur in the lung, mediastinum, pleura, and chest wall. Angiosarcoma, leiomyosarcoma, rhabdomyosarcoma, and mesothelioma (sarcomatoid variant) are the most common primary intrathoracic sarcomas. Ewing sarcoma, primitive neuroectodermal tumor, chondrosarcoma, malignant fibrous histiocytoma, osteosarcoma, synovial sarcoma, and fibrosarcoma usually arise in the chest wall. Although primary thoracic sarcomas commonly manifest as large, heterogeneous masses, they have a wide spectrum of radiologic manifestations, including solitary pulmonary nodules, central endobronchial tumors, and intraluminal masses within the pulmonary arteries. The different histologic types of sarcomas are frequently indistinguishable at radiologic analysis. However, differences in clinical presentation and the location of the tumor, as well as morphologic features such as calcification within the mass and rib involvement, can be useful in suggesting the appropriate diagnosis. For example, a large rib mass in a child with fever and malaise indicates a Ewing sarcoma, a mass with a calcified matrix is likely a chondrosarcoma or osteosarcoma, and a pulmonary artery mass is likely a leiomyosarcoma. 相似文献
105.
We investigated whether cigarette smoking, measured by follicular fluid
concentrations of cotinine (a major metabolite of nicotine), affects the
maturity of oocytes from women undergoing in-vitro fertilization (IVF) and
embryo transfer. In 234 women, follicular fluid samples were assessed for
cotinine and their 2020 oocytes were assessed for maturity stage. Data on
individual proportions of oocytes which were mature (OM) and were
fertilized (OF) were analysed by regression in relation to age and
follicular fluid cotinine. OF gave an independent assessment of oocyte
maturity. Both age and follicular fluid cotinine entered the OM and OF
regressions and were significant. The age-adjusted regression coefficients
for log cotinine were positive; greater cotinine concentrations usually
accompanied greater OM and OF. The cotinine effect on OM was positive in
younger women, but it became negative (decreased OM with increasing
cotinine concentrations) in older women (> or = 40 years). We further
found in older women an average reduction of approximately 50% in the
number of mature oocytes; this reduced number was lower than the number of
embryos usually transferred. Smoking can reduce the number of mature
oocytes even further, therefore risking a negative IVF-embryo transfer
outcome. This may be the reason why the negative effects of smoking become
clinically detectable in older women.
相似文献
106.
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108.
Overdistraction and derotation of the scoliotic spine during surgery represent potential complications that could lead to spinal cord dysfunction and paralysis. Neuronal loss and, consequently, the inability to regain function may be attributable to primary damage (eg, mechanical), secondary cell death (eg, such as that produced by ischemia) or a combination of both. Beyond intraoperative recognition and removal of the rods, effective strategies to prevent this neuronal loss have yet to be developed. This emphasizes the need for a clearer understanding of the molecular events that contribute to neuronal injury in the central nervous system. Considerable evidence has indicated that the excitatory transmitter L-glutamate and the N-methyl-D-aspartate (NMDA) excitatory amino acid receptor may contribute to the secondary neuronal death observed in a wide variety of neurological insults, including ischemia. The current investigation was undertaken to elucidate the potential role of the NMDA receptor in spinal cord pathology. Isolated rat spinal cords were exposed to anoxic physiologic solutions in the presence and absence of Ca++, NMDA receptor agonists, and a noncompetitive NMDA receptor antagonist. The extent of neuronal damage was assessed by quantitating the degradation of the cytoskeletal neurofilament protein. A substantial increase in the loss of neurofilament protein was observed in spinal cords exposed to anoxic conditions in the presence of Ca++ as compared with the absence of Ca++. Exposure to excitatory amino acid agonists (L-glutamate or NMDA) further potentiated the degradation of the neurofilament protein; an effect that was reversed by a noncompetitive NMDA receptor antagonist.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
109.
Papillary endolymphatic sac tumors: CT, MR imaging, and angiographic findings in 20 patients 总被引:6,自引:0,他引:6
110.