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1.
Hysterosalpingography was performed in 31 patients by means of a low-dose scanning-beam digital radiographic system. The technique permits adequate evaluation of gynecologic abnormalities while allowing significant reduction in radiation: 2.4-mR (6.1 X 10(-7) C/kg) exposure to the skin and 0.7-mrad (7 X 10(-6) Gy) mean dose to the ovaries per image obtained. Sixteen patients demonstrated readily recognizable and documented abnormalities, corroborated by laparoscopy, laparotomy, or other supportive evidence.  相似文献   
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This book is designed as a guide to practical obstetric anaesthesiaand aims to be a quick reference for trainees and consultantanaesthetists working in this area. The contents section showsclearly the chapters together  相似文献   
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Isolated sperm from normo-, oligo- and astheno-spermic men were incubated for 20 h in medium supplemented with 8% heat-inactivated or untreated human serum, and in medium with heated or untreated serum deficient in complement factor C3. Before and after incubation, sperm motility was assessed by means of a computer-assisted semen analyser. The results did not show significant differences between the motility of sperm incubated in heated or untreated serum. It is concluded that heating of homologous serum is not necessary for preserving sperm motility and in some cases may even be disadvantageous.  相似文献   
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Thalidomide is an inhibitor of angiogenesis.   总被引:33,自引:0,他引:33       下载免费PDF全文
Thalidomide is a potent teratogen causing dysmelia (stunted limb growth) in humans. We have demonstrated that orally administered thalidomide is an inhibitor of angiogenesis induced by basic fibroblast growth factor in a rabbit cornea micropocket assay. Experiments including the analysis of thalidomide analogs revealed that the antiangiogenic activity correlated with the teratogenicity but not with the sedative or the mild immunosuppressive properties of thalidomide. Electron microscopic examination of the corneal neovascularization of thalidomide-treated rabbits revealed specific ultrastructural changes similar to those seen in the deformed limb bud vasculature of thalidomide-treated embryos. These experiments shed light on the mechanism of thalidomide's teratogenicity and hold promise for the potential use of thalidomide as an orally administered drug for the treatment of many diverse diseases dependent on angiogenesis.  相似文献   
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OBJECTIVE: To examine hemodynamic changes following endovascular embolization in newborn infants with vein of Galen malformation and severe cardiac failure in the first week of life. STUDY DESIGN: Over a recent 5-year period, nine such infants were identified. In seven of these infants, changes in arterial blood pressure were analyzed in relation to the timing of embolization procedures. RESULTS: A significant increase in arterial blood pressure was noted after most embolizations. In two infants, this systemic hypertension was severe and treated using intravenous antihypertensive drugs. Both infants subsequently developed complete infarction of both cerebral hemispheres with sparing of the brainstem and cerebellum. Mortality in the nine infants was 33%, and 83% of the survivors were neurologically normal or near normal at follow-up. CONCLUSION: The systemic hypertension observed following endovascular embolizations may provide a protective mechanism to maintain cerebral blood flow after reperfusion injury. Lowering blood pressure in this situation may therefore be detrimental.  相似文献   
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Image-directed percutaneous biopsies with a biopsy gun   总被引:3,自引:0,他引:3  
Core tissue for histologic study is believed by many pathologists to be more diagnostic than material from needle aspiration. Recently, a biopsy "gun" has been introduced, which simplifies core biopsies. With this device, 182 biopsies of multiple anatomic sites were performed with ultrasonic, computed tomographic, and fluoroscopic guidance and 18-gauge needles. High-quality histopathologic specimens were obtained in 177 of the biopsies, and diagnostic target tissue was obtained in 167. Only three significant complications occurred: one bleeding complication that required transfusion and two cases of pneumothorax that necessitated placement of chest tubes. The biopsy gun eliminated the disjointed movements of conventional "skinny" needle biopsies, and none of the samples demonstrated significant "crush" artifact or obscuring blood, problems that are commonly associated with manual biopsy techniques. Patient discomfort was decreased with this system compared with that of manual biopsies, and the total procedure time was reduced. Because of these distinct advantages, the authors now use the biopsy gun exclusively for all percutaneous biopsies and recommend that other institutions consider the use of this biopsy method.  相似文献   
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Cone snails use venom containing a cocktail of peptides ('conopeptides') to capture their prey. Many of these peptides also target mammalian receptors, often with exquisite selectivity. Here we report the discovery of two new classes of conopeptides. One class targets alpha1-adrenoceptors (rho-TIA from the fish-hunting Conus tulipa), and the second class targets the neuronal noradrenaline transporter (chi-MrIA and chi-MrIB from the mollusk-hunting C. marmoreus). rho-TIA and chi-MrIA selectively modulate these important membrane-bound proteins. Both peptides act as reversible non-competitive inhibitors and provide alternative avenues for the identification of inhibitor drugs.  相似文献   
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