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11.
A series of 100 cases of pelvic fracture secondary to violent trauma were reviewed and divided into two anatomic groups, those with pure anterior arch fractures (57 patients) and those with posterior fractures (43 patients). By this classification, mortality and associated injury are shown to be markedly increased in those patients with posterior fractures. A detailed study of the major complications has shown that a conservative approach to these injuries is probably the safest for the patient. Major blood loss is the rule rather than the exception and restoration of an adequate circulating volume by transfusion should precede operative attempts to control continuing retroperitoneal hemorrhage.  相似文献   
12.
Some unsaturated fatty acids were found to inhibit the growth of Staphylococcus aureus. Their effectiveness was related both to the degree of unsaturation and to the configuration of the molecule about the double bonds. Both linoleic acid and linolenic acid increased the proportion of plasmid-negative bacteria in a growing culture of bacteria containing a penicillinase plasmid. This was not due to a 'curing' effect of the fatty acids but was the result of greater sensitivity of the growth of bacteria containing penicillinase plasmid to inhibition by the unsaturated fatty acids. The presence of a plasmid conferring resistance to tetracycline, however, did not make the bacterium more sensitive to inhibition by linoleic or linolenic acids.  相似文献   
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A high frequency of meningeal lesions was found at autopsy in foals dying perinatally. Such lesions are considered an index of injury to the fetal central nervous system, from trauma and/or hypoxia during birth. Their incidence in the sample examined (26 foals) is similar to that observed in the perinatal mortality of lambs and calves.  相似文献   
14.
1. Isolated rat kidneys were perfused at a constant pressure of 90 mmHg in a single-pass system with either a cell-free medium or a suspension of washed bovine red blood cells, free of the components of the renin-angiotensin system. In red blood cell perfused kidneys renal haemodynamics and sodium reabsorption corresponded closer to values observed in the intact rat than in cell-free perfused kidneys. 2. In red blood cell-perfused kidneys in the absence of plasma renin substrate autoregulation of renal blood flow was almost complete at pressures above 90 mmHg, provided that perfusion pressure was changed rapidly. 3. Renin release varied inversely with perfusion pressure within a pressure range from 50 to 150 mmHg; the greatest changes of renin release occurred, when perfusion pressure was reduced from 90 to 70 mmHg; maximal stimulation of renin release was observed at 50 mmHg. After reduction of perfusion pressure, renin release immediately started to rise and reached a new level within 5 min. Local reduction of perfusion pressure in small arteries and arterioles by the injection of microspheres induced a short-lasting decrease in renal plasma flow and a transient stimulation of renin release. 4. High concentrations of furosemide stimulated renin release by a direct intrarenal mechanism. 5. Isoproterenol stimulated renin release in low concentrations without a concomitant vasodilation, whereas high concentrations induced an increase in both renal plasma flow and renin release. The effects of isoproterenol were completely blocked by propranolol. 6. Sodium nitroprusside induced similar increases in renal plasma flow, as did high concentrations of isoproterenol, but only a small and slow increase in renin release was observed. 7. Angiotensin II (AII) suppressed renin release in concentrations corresponding to plasma levels measured in the intact rat independently of its vasoconstrictor effects, whereas vasopressin in antidiuretic concentrations did not affect renin release. 8. AII, AI, synthetic tetradecapeptide renin substrate (TDP), crude and purified rat plasma renin substrate induced a dose-dependent reduction in renal plasma flow. SQ 20 881, a competitive inhibitor of converting enzyme, and low doses of 1-Sar-8-Ala-AII (saralasin), a competitive antagonist of AII, did not change renal plasma flow, whereas high concentrations of saralasin had a vasoconstrictor effect on their own. 9. Saralasin inhibited the vasoconstrictor effects of AII and TDP to a similar degree. SQ 20 881 inhibited the vasoconstrictor effects of AI and purified renin substrate, but did not influence the actions of TDP and the crude renin substrate preparation. 10. From these data it is concluded, that AI is converted into AII within the kidney at a rate of 1-2%. The vasoconstriction induced by the crude renin substrate probably does not involve the AII receptors. TDP may act by itself on the AII receptors or via the direct intrarenal formation of AII...  相似文献   
15.
The effect of catheter placement in the abdominal aorta on the blood flow and oxygenation of lower extremities was evaluated in 30 New Zealand rabbits, weighing 0.55-3.5 kg, by inserting 3.5 and 5.0 French polyvinyl chloride catheters, of the type commonly used for umbilical artery catheterization, through the femoral artery, advancing 15-20 cm, and leaving in place for 10-30 min. Arterial blood pressure (BP), common iliac artery blood flow (BF), gracilis muscle tissue oxygen availability (O2a), and subcutaneous temperature (T) in the foot were continuously monitored before and during catheter placement and after withdrawal. There were no changes in the physiologic variables measured in the contralateral leg when the catheter remained below the aortic bifurcation; however, when the catheter was advanced 15-20 cm into the abdominal aorta, a decrease in lower extremity BF, O2a, and T occurred. Because the length of catheter insertion was maintained constant in each animal, the decreases in BF, O2a, and T are related to the relative dimensions of the vessel and the catheter. The ratio of catheter to vessel diamter, in addition to the site of catheter placement, should be considered during the clinical application of arterial catheters. Reduction in blood flow could be detected by continuous differential monitoring of core and extremity temperature or extremity muscle oxygen availability.  相似文献   
16.
More than 600 cases of ovarian tumors were analyzed for histological type, age of patient, bilateral occurrence, mobility and malignant degeneration in restant ovaries. Tumors of germinal epithelial origin show the highest incidence (24%) of malignant degeneration, tumors of germ cells the lowest (3,5%). Incidence of malignant degeneration increases in relation to the age of the patient from 2% (and under 30 years) to 36,5% (60-70 years). Each form of tumor has its typical age peak, which is about 20 years higher for carcinomas than for their benign counterpart. Bilateral ovarian tumors are malignant in 29%, one-sided only in 13%. Among freely movable ovarian tumors, only 6% enclose a malignant tumor, among adhaerent ones 34%. The examination of the prognosis of granulosacell-tumors, dysgerminomas and teratoblastomas is based on a larger material.  相似文献   
17.
An attempt has been made to study the desizing of polyvinyl alcohol (PVA) starch-based organic cotton fabric using alpha-amylase enzyme with various process parameters such as enzyme concentration, temperature and reaction time. These process variables are selected based on the Box–Behnken design of experiment and the output of experiment resulted in weight loss of the fabric and their results are optimized with minimum error. The test results are analyzed using Design-Expert software 8.0 to predict the optimum process parameters to achieve the required desizing efficiency and their results are compared with actual trials. The alpha-amylase enzyme kinetics are studied at various concentrations, temperatures and reaction times to optimize the desizing process parameters. The performance of desizing was assessed by an iodine test and FTIR results to confirm the degradation of PVA starch in the desized organic cotton fabrics.  相似文献   
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19.
Food Science and Biotechnology - Despite centuries of developing strategies to prevent food-associated illnesses, food safety remains a significant concern, even with multiple technological...  相似文献   
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