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11.
Hemodynamic, respiratory, and regional blood flow measurements were carried out in two groups of monkeys at three roughly equivalent stages of endotoxin and hemorrhagic shock. Comparisons revealed characteristic differences at the two early stages, particularly in systemic vascular resistance and the pattern of distribution of cardiac output. However, at the final stage of shock, these patterns had merged and there were no characteristic differences between the two groups. The pathologic significance of these findings, in terms of the endotoxin theory of irreversible hemorrhagic shock and the realtive contributions of vasoactive humoral substances at various stages of the two forms of shock, is discussed.  相似文献   
12.
Fusion of capacitated spermatozoa with the vitelline membrane, but not actual penetration, appears to initiate the cortical reaction in hamster eggs. The reaction can be artificially induced by the application of positively charged particles to the vitelline surface, a situation which may normally be prevented by the zona pellucida. Exposure of hamster eggs to neuraminidase, to lectins (concanavalin A and phytohaemagglutinin-P), to a monovalent ionophore (boromycin) and to 1,3-bis(4-chlorocinnamylideneamino)guanidine elicits a cortical granule discharge resulting in a block to fertilization. These agents all appear to act by inducing depolarization of the vitelline membrane.  相似文献   
13.
Two passive haemagglutination methods for detecting HBsAg were compared. In general, the method using turkey erythrocytes was found preferable to the method employing sheep cells since it is more rapid and more sensitive, and less frequently gave rise to false positive reactions with sera from staff, blood donors, and patients not receiving haemodialysis. The turkey cell test gives rise to more false positive screen tests than the sheep cell test when monitoring renal dialysis patients since approximately 10% of the sera of these patients were found to contain turkey cell agglutinins, but this presents no particular difficulty if the recommended absorption procedures are used.  相似文献   
14.
AUTOGRP is an interactive computer system designed to facilitate rapid analysis of complex medical information. AUTOGRP allows the clinical or administrative expertise of the user to be combined with sophisticated computer techniques to permit rapid information retrieval, hypothesis testing, development of norms, and identification of deviant cases. This interaction yields results of a uniquely high statistical and medical quality. AUTOGRP has been used to aid in understanding the process of patient care management in a variety of settings in order to enhance the effectiveness of decision-making from both a medical and management point of view.  相似文献   
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The relationship of education to both actual blood pressure and the prevalence of high blood pressure, based on a systolic pressure of 160 mm Hg or greater or a diastolic pressure of 95 mm Hg or greater, was analyzed among 27,033 men and women, white and black, age 25-44 and 45-64, from the Chicago Heart Association Detection Project in Industry. The educational status of each individual was categorized as not a high school graduate, high school graduate, some college, or college graduate. A statistically significant inverse association between education and high blood pressure was present in all groups of whites. This association could not be "accounted for" by differences in age, relative weight, and heart rate among the educational strata. Controlling for these variables did, however, lessen the association. Among black males a significant inverse association between education level and blood pressure was found for the younger group. For the older black males there was a clear inverse association although with the small numbers it did not achieve statistical significance. For black females there was no clear association.  相似文献   
17.
beta,beta-Dichloro- and beta,beta,beta-trifluoroalanine irreversibly inactivate a number of pyridoxal phosphate dependent enzymes which catalyze beta- or gamma-elimination reactions. The inactivation is time dependent and the rate of inactivation is first order in enzyme concentration. This suggests that inactivation is due to covalent modification of the enzyme by a species generated at the active site from the polyhaloalanine (i.e., suicide inactivation). Monohaloalanines are substrates and do not inactivate. For gamma-cystathionase, covalent and stoichiometric attachment of [1-14C]beta,beta,beta-trifluoroalanine was shown. It is proposed that the mechanism of inactivation involves Schiff base formation between inactivator and enzyme-bound pyridoxal and subsequent elimination of HC1 from dichloroalanine or HF from trifluoroalanine. This results in the formation of a beta-halo-alpha,beta unsaturated imine, an activated Michael acceptor. Michael addition of a nucleophile at the active site leads to covalent labeling of the enzyme and inactivation. Alanine racemase is also inactivated by the two polyhaloalanines. Glutamate-pyruvate and gultamate-oxaloacetate transaminase are inactivated by monohaloalanines but not by polyhaloalanines.  相似文献   
18.
Karyotypes were prepared from peripheral blood leukocytes in 77 couples in whom there was no apparent cause for recurrent spontaneous abortion. In addition to conventional staining, chromosomes were stained by the new technics for Q-, G-, or C-banding. Translocations were found in 5 of 154 persons (3.25% or 1:31 individuals). The frequency of translocations in the general adult population is 0.4% (1:255). Two translocations were apparent only with the new technics for banding. The incidence of chromosomal microanomalies was 7.79% (2.6% in the general population). Karyotyping of couples with recurrent abortion is recommended, with use of the new staining technics.  相似文献   
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20.
Seven obese and five normal weight patients were studied before, during and after one hour of methoxyflurane-nitrous oxide anaesthesia during peripheral surgical operations and compared with eight patients of normal weight anaesthetized with nitrous oxide-meperidine and d-tubocurare. Estimates were made of renal function, including serum and urinary electrolytes, osmolarity, uric acid, urea and creatinine. Renal clearances for the latter three substances were also calculated. Serum and urinary inorganic and organic fluoride concentrations were measured, as were renal clearances. This low dose methoxyflurane anaesthesia resulted only in a decrease in uric acid clearance among all the measures, when compared to the meperidine-nitrous oxide controls. The clearance of uric acid remained depressed for longer in the obese patients, but otherwise they did not differ from the normal weight patients. It is possible but not proven that depressed uric acid clearance may be related to the organic fluoride metabolite and an early indicator of methoxyflurane renal toxicity. The previously documented biotransformation of methoxyflurane was seen in this study. A double peak in serum inorganic fluoride was shown in all patients but one. Rather large differences in peak levels of serum inorganic fluoride occurred. The only significant difference between the obese and normal weight patients as far as fluoride metabolism was concerned was a greater variability in the serum inorganic fluoride levels in the obese patients. It would appear that the obese patient metabolizes methoxyflurane in a quantitatively if not qualitatively different fashion than the normal weight patient, perhaps because of fatty infiltration of the liver. Caution is advised in the use of methoxyflurane for more than 90 minutes of low concentration administration in view of the unpredictability of the biotransformation.  相似文献   
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