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201.
Besides a thermolabile inhibitor of tissue thromboplastin a thermostable inhibitor was found in human blood serum; molecular weight of the inhibitor (estimated by gel filtration) is 210000-235000 daltons, while molecular weight of a thermolabile inhibitor--480000 daltons. Inhibition of the thrombin formation system by the termostable inhibitor was reversible and was characterized kinetically as a mixed type of inhibition. Both inhibitors were found in blood of rats. Their content varied irrespectively of the state of hemocoagulation. Content of the thermostable inhibitor was distinctly decreased in blood serum after the blockade of reticuloendothelial system by administration of tripane blue.  相似文献   
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Annually, numerous couples prepare for childbirth through Lamaze childbirth education classes. Research on various portions of the Lamaze method has used the cold pressor as an analogue for labor. In this experiment, pregnant women who had attended either (a) Lamaze classes which taught pain control methods (n = 22), or (b) Red Cross parenting classes which did not teach pain control methods (n = 7), and students who received either (c) brief Lamaze training (n = 10), or (d) no training (n = 10), were tested on the cold pressor. Pregnant women were also interviewed after the delivery of their children. On the cold pressor, clinically trained Lamaze women were superior (longer tolerance, less pain and/or distress) to clinical control (Red Cross) women, which were equal to student Lamaze trained women. All groups performed better than student controls. Post hoc analyses showed that women who managed labor pain well performed better on the cold pressor task than women who did not manage labor pain well. This experiment established some limits for applying analogue results to childbirth. Moreover, it showed that women who attended Lamaze classes received less medication during labor than women who attended Red Cross classes; however, it was not clear whether this difference was due to the Lamaze classes per se, or to other uncontrolled variables.  相似文献   
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The epidemicity of poliomyelitis in Israel since 1950 is reviewed, and the influence of the mass immigration which took place between 1948 and 1952 is discussed. Age distribution and attack-rates among Arabs, among Jewish population-groups originating in different countries, and among old residents and new immigrants, are examined. It is suggested that the change from endemicity to epidemicity of the disease may have been due to general overcrowding during the pre-epidemic period, and to enhanced circulation of virus (type 1), and a resulting increase in its pathogenicity.  相似文献   
206.
Tumor cells from eight adult patients with T-cell chronic malignancies were investigated with a series of monoclonal antibodies recognizing T-cell differentiation antigens. This series allowed definition of discrete subpopulations of mature T cells with functional specialization. All six patients with Sézary syndrome and one patient with T-chronic lymphocytic leukemia had cells with the same phenotype as normal helper/inducer T cells, whereas the other patient with T-chronic lymphocytic leukemia had cell with the same phenotype as normal cytotoxic/suppressor T cells. Some clinical manifestations observed in these patients may reflect retention of functional activities by their malignant cells.  相似文献   
207.
Fifty extracted human maxillary anterior teeth were biomechanically instrumented and divided into five equal groups, four experimental and a control. The teeth in the experimental groups had their root surface coated with one of four sealants; epoxy, casting resin, sticky wax, or nail polish. The roots of the remaining teeth were not coated and served as controls. All of the teeth were mounted in the caps of scintillation vials. Five microliters of [3H]uridine were deposited in the root canal space and disintegration counts were obtained over time periods of 1, 4, 8, 12, and 36 wk. At the conclusion of the experiment, sticky wax was demonstrated to provide a superior seal (p < 0.0001).  相似文献   
208.
A statistical method is proposed to establish milk discard time for the data set described in Part I (preceding paper). Results are compared with those from the Food and Drug Administration (FDA)-recommended method. The milk discard time is established on the basis of a calculated tolerance limit. This limit provides 95% confidence that 99% of the population residue would assay below the permitted concentration (10 ppb for SDM). Unlike the FDA method, the proposed method allows easy calculation and requires no assumptions in drug depletion rate over time. For a permitted concentration of 10 ppb, both methods confirm the present 60-h discard time for SDM when it is assumed that no more than 1/3 of the milk came from treated cows.  相似文献   
209.
The extent of loss of hydrocyanic acid during the fermentation of cassava tubers selected from both sweet and bitter varieties in the traditional method (whole unpeeled tubers) compared with the fermentation of peeled tubers and crushed pulps with or without the addition of water. Although the traditional fermentation is terminated after 3–4 days, in this study the fermentation was allowed to proceed for 8 days. Loss of cyanide from the whole tubers was 8047% after 8 days and was only 51–53% after 4 days. Loss of cyanide from the whole sweet tuber was not significant after 5 days. The loss of cyanide from the peeled tubers was comparable to the whole tubers after 8 days of fermentation. However, there was a marked decrease in free cyanide in the 1st day of fermentation of the peeled tubers compared to whole tubers. The loss in cyanide in the crushed pulp, which occurred primarily in the 1st day, appears to be due to the action of endogenous linamarase rather than hydrolysis by fermentation. When water is added to the crushed pulp the reduction in cyanide was 83–91% with marked decrease in bound cyanide in the 1st day of fermentation. It seems that autohydrolysis is enhanced by addition of water to the crushed pulp.  相似文献   
210.
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