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991.
992.
993.
A method of instituting hydrolysis by using enzymes of the examined liver is proposed as an adjunct to the formerly elaborated fluorometric procedure of determining folacin in the liver. The fermentative hydrolysis is conducted in two stages. The purpose of the first of them is to split the combined form of folacin under the effect of the examined liver conjugases; the second stage involves transformation of xanthopterin contained in the liver into leucopterin by xanthinoxidase of the liver. When utilizing enzymes of the examined liver the need for producing and application of the enzymatic preparation made of the pig kidneys falls away, this simplifying the fluorometric determination of folacin in the liver and increasing its accuracy.  相似文献   
994.
An operant technique was used to train 10-wk.-old infants on a simultaneous discrimination task with a checkerboard cube and a bull's-eye sphere presented in a stationary form. Discrimination testing with the objects in motion and with the objects stationary indicated that infants are able to discriminate between simultaneously presented objects whether stationary or in motion. The results are contrasted to T. G. R. Bower's assessment of infants' utilization of features in perceiving moving objects.  相似文献   
995.
Decrease in the constrictive reaction of the intra- and extracranial vessels to noradrenaline was observed in animals with cardiogenic shock; in acute experiments on anesthetized cats by resistography and rehoencephalography. Under these conditions the rise of the systemic arterial pressure under the influence of noradrenaline promoted passive dilatation of the cerebral vessels and an increase of their blood filling.  相似文献   
996.
997.
An analysis of 16 cases of secondary hemorrhages in injuries of bones and soft tissues of the extremities is presented. The secondary hemorrhages occurred within the period from 16 hours to 27 days after the trauma. Angiographic study is a valuable adjunct for establishing the correct diagnosis. Arrosion of large arterial trunks was the adjunct for establishing the correct diagnosis. Arrosion of large arterial trunks was the basic cause of the secondary hemorrhage. In the prophylaxis of the latter a special importance is attached to a wide wound dissection in primary surgical treatment and to secure hemostasis, especially in the body portions having multilayer musculature.  相似文献   
998.
The line spread function (LSF) and modulation transfer function (MTF) of 9 rare-earth screen/film systems were measured and compared with those of two fast calcium tungstate systems, using double-emulsion films sandwiched between two screens and mounted in regular cassettes. The LSFs were found to fit exponential functions. These results indicate that the increased sensitivity of rare-earth phosphors over calcium tungstate can be used to construct screens with a higher MTF or increased speed. The fast rare-earth systems allow the use of smaller focal spots for increased resolution while reducing the radiation dose to the patient.  相似文献   
999.
Twenty cases of immature teratoma of the ovary with a neural component are analyzed. A plea is made for use of the nomenclature adopted from the new World Health Organization classification of ovarian tumors, the past confusion over terminology and histogenesis of this rare tumor is discussed. All the primary tumors in the present series contained at least some immature tissues (predominantly of neural origin) and were thus graded from 1 to 3 according to the criteria of Thurlbeck and Scully. No grade 0 tumors ("benign solid teratomas") were identified. We believe that thorough sectioning almost always insures the identification of immature elements. The prognosis was closely related to the histologic grade, but correlated poorly withthe clinical stage, the latter being influenced by the common finding (25 per cent of the cases in this series) of peritoneal implants composed exclusively of mature glial tissue, which is associated with a benign clinical evolution. This phenomenon of maturation or differentiation appears to be the rule rather than the exception in this tumor, since implants are usually of better or equal differentiation when compared with their primary tumors and older patients tend to have lower grade tumors than younger patients. Since the majority of patients with this tumor are young, primary surgical therapy should be conservative, unilateral salpingooophorectomy often being sufficient. Spontaneous or operative rupture of the tumor capsule carries an increased risk of subsequent dissemination. We have noted impressive clinical responses in patients with disseminated tumors of a high histologic grade after treatment with triple chemotherapy (vincristine, actinomycin D, and cyclophosphamide) but do not recommend adjuvant therapy in patients with only grade 0 implants.  相似文献   
1000.
通过对多原子分子配分函数在常温情况下的具体讨论,详细分析了O2和CO2气体分子定压摩尔热容理论值与实验值差异的原因。  相似文献   
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