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排序方式: 共有573条查询结果,搜索用时 46 毫秒
81.
82.
阿魏酸钠对乙醇所致小鼠肝脏抗氧化功能改变的拮抗作用 总被引:19,自引:0,他引:19
研究了不同剂量乙醇对小鼠抗氧化和解毒功能的影响以及阿魏酸钠的拮抗作用。结果表明,大剂量乙醇(11.4g·kg-1ig)引起肝脏GSH-Px活性升高的同时,肝脏GSH-Re,SOD和GST活性降低,GSH耗竭,而血清GST升高;阿魏酸钠(100mg·kg-1ig,qd×10)预处理则明显拮抗大剂量乙醇所致的上述改变。表明阿魏酸钠对急性乙醇所致肝损害具有良好保护作用,其机理可能与提高GSH氧化还原酶功能、增加SOD活性和增强GSH结合反应有关。研究结果还提示,血清GST水平是反映乙醇性肝损害的灵敏指标。 相似文献
83.
Visibility of gallstone fragments at US and fluoroscopy: implications for monitoring gallstone lithotripsy 总被引:1,自引:0,他引:1
To assess the value of ultrasound (US), fluoroscopy, and spot radiography in the detection, counting, and measurement of gallstone fragments during lithotripsy, in vitro visibility studies were conducted on fragments from 20 stones. Fluoroscopic visibility was evaluated during and after lithotripsy on 185 fragments placed in an anthropomorphic phantom. Three US experiments were performed on the fragments to study the visibility of fragments as a function of size, the accuracy of the count with large numbers of fragments, and the ability of observers to detect and count fragments larger than both 4 mm and 5 mm. With fluoroscopy, fragment detection rates ranged from 20% (fragments larger than 2.5 mm) to 80% (fragments larger than 4.5 mm). With US, all fragments larger than 1.5 mm were detected, and US was significantly better than fluoroscopy and spot radiography for detection of fragments 2.5 mm or smaller. US was also more accurate than fluoroscopy (11% vs 59% error) in the assessment of the number of fragments. When fragments larger than 4 mm or 5 mm were being counted with US, 92% of the fragments were visualized. The results suggest that US is more accurate for monitoring gallstone lithotripsy than fluoroscopy or spot radiography. 相似文献
84.
U PODDAR Y CHAWLA RK DHIMAN K VAIPHEI RK VASISHTA JB DILAWARI 《Journal of gastroenterology and hepatology》1998,13(1):109-111
Ascites may be associated with fulminant hepatic failure (FHF), but spontaneous bacterial peritonitis (SBP) is an extremely rare complication. We report on two patients with FHF who developed SBP. One patient died and the other recovered. 相似文献
85.
86.
1. Ketamine has a number of effects that suggest that it may interact with α- and β-adrenoceptors. To date, the experimental evidence for this has been indirect and has been based on physiological studies using competitive blocking agents. In the present study we sought to determine from receptor binding studies whether ketamine binds directly to α- and β-adrenoceptors. 2. Membrane preparations o. α1- and β2-adrenergic binding sites were obtained from urinary bladder and urethrae of sheep. These binding sites were characterized by saturation analyses using [3H]-prazosin for α1-adrenoceptor binding sites and [125I]-cyanopindolol (CYP) for the β2-adrenoceptor binding sites. The receptors were further characterized by displacement studies using selective and non-selective antagonists. 3. Studies in which ketamine was used to displac. [3H]-prazosin revealed a Kd of 3.40±1.23× 10?3 mol/L for ketamine binding to ai-adrenoceptors. Displacement studies of [125I]-CYP by ketamine showed a Kd of 0.35±0.03× 10?3 mol/L for ketamine binding to β2-adrenoceptors. 4. We conclude that ketamine interacts directly with both ai- an. β2-adrenoceptors and that such interactions probably explain the reported effects of this agent on the vasculature and the bronchial tree. 相似文献
87.
88.
89.
Computed tomographic study of hormone-secreting microadenomas 总被引:1,自引:0,他引:1
Hemminghytt S; Kalkhoff RK; Daniels DL; Williams AL; Grogan JP; Haughton VM 《Radiology》1983,146(1):65
90.
The advantages of delayed imaging and radiographic correlation in scintigraphic localization of gastrointestinal bleeding 总被引:1,自引:0,他引:1
Two cases in which gastrointestinal bleeding was localized by serial scintigraphic imaging with red blood cells labeled in vivo with 99mTc-PYP are reported. The importance of both early serial imaging and delayed imaging and of the correlation with other radiographic techniques is demonstrated. Reflux of blood from the sigmoid into the proximal colon was observed in both cases. In one case, contrast material injected into a resected specimen confirmed the scintigraphic localization of the site of bleeding. 相似文献