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排序方式: 共有10000条查询结果,搜索用时 640 毫秒
981.
982.
Increased production of peroxidation products associated with cardiac operations. Evidence for free radical generation 总被引:7,自引:0,他引:7
D Royston J S Fleming J B Desai S Westaby K M Taylor 《The Journal of thoracic and cardiovascular surgery》1986,91(5):759-766
We investigated the degree and time course of neutrophil sequestration into human lungs during cardiac operations. At the same time, measurement of the concentration of peroxidation products in the plasma was used as an index of oxidant free radical activity. The study was performed in two groups of patients. Group A (n = 11) had studies extending over the entire operative period and showed a highly significant sequestration of neutrophils into the lung, together with a highly significant (p less than 0.001) rise in peroxidation products from 2.8 +/- 0.12 nmol/ml(mean +/- standard error of the mean)before bypass to a peak of 5.05 +/- 0.13 nmol/ml at the end of bypass. As these changes occurred only during the time after release of the aortic cross-clamp, we investigated this period in more detail in a second group of patients (Group B, n = 7). Results from this group showed that significant release of peroxidation products occurred at the same time as pulmonary neutrophil sequestration. This study has produced evidence of increased oxidant activity in the lung associated with cardiac operations. Nevertheless, it is not known whether the neutrophils sequestered into the lung alone induced the increased activity. Similarly, whether neutrophil-derived oxidant species are the sole cause of lung tissue injury remains unproved. 相似文献
983.
A 6-week-old child with esophageal perforation secondary to a misplaced gastrostomy Foley balloon is described. She was treated successfully with chest tube drainage, antibiotics, and total parental nutrition. This may be an alternative method of treating this rare complication of gastrostomy. 相似文献
984.
985.
K Murata H Itoh G Todo T Itoh M Kanaoka M Furuta K Torizuka 《Investigative radiology》1986,21(1):24-30
This study was undertaken to clarify the microvascular anatomy of the normal human bronchial circulation, focusing on the bronchial venous system and its communication with the pulmonary circulation. Ten normal lungs obtained at autopsy were studied. Bronchial arteriography was performed in six lungs, pulmonary arteriography in two lungs, and pulmonary venography in another two. Using radiologic methods, including microradiography, and serial histologic sections, we found numerous bronchial venous plexuses around the airways and blood vessels into which the bronchial capillaries drained. Frequent communications of the venous plexuses with the pulmonary veins and neighboring alveolar capillaries were also demonstrated. The bronchial venous plexus and its close connection with the pulmonary circulation may be important in various pathologic conditions involving the interstitial space, such as interstitial pulmonary edema. 相似文献
986.
Approach to early diagnosis of acute mesenteric ischemia: evaluation in canine model 总被引:1,自引:0,他引:1
K Kido A Maenosone N Takasu M Nishina K Tokuda C Fujii A Kohama 《Nihon Geka Gakkai zasshi》1986,87(10):1352-1358
The high mortality rate of patients with acute mesenteric ischemia may be mainly due to the difficulty of making an early diagnosis. Many clinical and experimental studies have been attempted to make an early diagnosis in the view of history, physical examination, laboratory data, X-rays and angiographies. This study was undertaken to estimate the diagnostic value of twenty one laboratory parameters and three clinical parameters measured after superior mesenteric artery occlusion (SMAO) in the mongrel dogs. Consequently, the valuable diagnostic indicators of SMAO that statistically had significant difference were serum CPK isoenzyme-BB, serum CPK isoenzyme-MB, serum inorganic phosphate, serum calcium and base excess of arterial blood gas analysis. In these indicators, serum CPK isoenzyme-BB, serum inorganic phosphate and serum calcium were especially valuable indicators of its early diagnosis, because they showed significant change in the early phase after SMAO. However, other indicators showed significant change within eighteen hours after SMAO. Therefore, if these indicators are able to be examined in a case of abdominal emergency, they are considered to play a valuable role in the diagnosis of acute mesenteric ischemia. 相似文献
987.
This study measured the pressures under the three most commonly used digital tourniquets--the Penrose drain, the rolled rubber glove, and the rubber band. A miniature pressure transducer and a digital strain indicator were used to measure pressures generated by the various tourniquets. The rolled rubber glove technique was highly consistent, irrespective of the clinical experience of the subject, and uniformly generated pressures of less than 500 mm Hg. Pressures generated by Penrose drains and rubber bands were highly variable and were significantly greater than 500 mm Hg. The so-called calibrated Penrose drain generated the highest pressures in the study. The relationship between tourniquet pressures and neurovascular injury in the human digit is not clearly defined. 相似文献
988.
989.
990.
In experiments on mice and rats quipazine exerts a moderate and short-term anorexigenic activity. N-acyl quipazine derivatives are markedly less toxic, do not exert anorexigenic action and influence weakly the serotoninergic and adrenergic systems. 相似文献