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51.
H Biran JL Moake RC Reed JU Gutterman EM Hersh EJ Freireich GM Mavligit 《Canadian Metallurgical Quarterly》1976,34(5):493-499
Serum complement levels were assayed in 26 patients with disseminated cancer, who received immunotherapy with infusion of C. parvum. Complement activation, indicated by the consumption of C3 or C4 or both, was found in 46% of the patients. Serum samples showed direct correlation between decreased C3 and conversion of C3 proactivator, whereas such conversion did not occur when C4 alone was decreased. It is concluded that the bypass (properdin) pathway was activated in patients in whom C3 consumption was detected, while the classical (C1) pathway was activated in the patients with C4 consumption unaccompanied by C3 decrease. Direct correlation was observed between delayed cutaneous hypersensitivity reactions to recall antigens and the incidence of C. parvum-associated complement activation. 相似文献
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A longitudinal study evaluating the degree of rotation of the bimalleolar axis of tibia and fibula at birth, 6 month, 12 months and 24 months revealed a gradual statistically significant external rotation from a mean of 4 degrees at birth to a mean of 11 degrees at 24 months. There was no correlation with the sex or race of the child or with the age at which the child began independent walking. It is concluded that this external rotation is a part of normal growth and development of the infants' lower extremities. 相似文献
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The uni-arterial vascularisation of the lateral bilary duct makes it impossible to systematise the arteries which supply the common bile duct. Only the cystic artery is seen at coelio-mesenteric catheterization. The techniques essential for visualisation of the cystic artery are discussed, on the basis of one hundred coelio-mesenteric arteriograms: frequency of demonstration, origin, course, termination, calibre and length. The frequent finding of opacification of the wall of the gall bladder under normal conditions is stressed. 相似文献
56.
DP Wolf T Nishihara DM West RE Wyrick JL Hedrick 《Canadian Metallurgical Quarterly》1976,15(17):3671-3678
As a step toward defining in molecular terms the sperm-triggered block to polyspermy reaction established by the egg at fertilization, vitelline (VE) and fertilization (FE) envelopes were isolated from eggs of the Sounth African clawed toad Xenopus laevis and some of their physicochemical properties determined. Envelopes were isolated after lysis of the fertilized or unfertilized eggs by sieving techniques; isolated envelopes retained their in situ morphology as determined by electron microscopy. The isolated envelopes had different solubility properties and, in general, VE was more readily dissolved by aqueous solvents than FE, although both could be completely dissolved by detergents or chaotropic agents. Changes in envelope solubility correlated with the progression of the cortical reaction implicating a role for cortical granule material in modifying the solubility properties of the envelope. The VE and FE were composed of protein and carbohydrate with no lipid components detected. As determined by immunodiffusion experiments, the FE contained the same antigens as the VE plus components derived from the cortical granules and the innermost jelly layer, J. The macromolecular composition of the envelopes was determined by sodium dodecyl sulfate gel electrophoresis. The VE contained at least 11 glycoproteins with molecular weights ranging from 125 000 to less than 16 000 with two components (40 000 and 33 000) accounting for almost two-thirds of the total stainable material. The FE contained ten glycoproteins that had the same molecular weights as those in the VE. One glycoprotein component underwent a reduction in molecular weight from 77 000 to 67 500 when the VE was converted to the FE. This molecular weight change was interpreted as the probable result of limited proteolysis. In addition, the FE gel electrophoresis patterns contained macromolecular components derived from the cortical granules and jelly layer, J, consistent with the immunodiffusion experiments. These components were absent when the FE was prepared in the absence of Ca2+, suggesting a role for Ca2+ in binding the VE, cortical granules, and J components together. We concluded that the conversion of the glycoproteinaceous VE to FE at fertilization is caused by interaction of the VE with components from the cortical granules and jelly layer J. These interactions are of both a chemical and physical nature. 相似文献
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Allyl isothiocyanate (AITC) was given in doses of 0, 10, 20, or 40 mg/kg (5 days/week) by oral intubation to male rats for up to 6 weeks. The highest dosage level caused a decrease in body weight, thymus weight, blood glucose and serum globulin levels. Haematological examination revealed an increased percentage of neutrophils and a decreased percentage of lymphocytes after treatment for 2 weeks. Increased liver and adrenal weights were found in all test groups. Renal dysfunction was indicated by increased urinary aspartate amino-transferase activity, reduced urine volume and changes in the specific gravity of the urine. Histopathological changes were observed in the kidneys of animals at dosages of 20 and 40 mg/kg and in the livers of animals at the highest dosage level. 相似文献
60.
The study of cooperative ligand binding among the four subunits of haemoglobin has played a central role in the understanding of allosteric transitions in a large number of enzymes. Haem iron out-of-plane motion has been suggested to be the trigger for the cooperative transition of haemoglobin. To function as a trigger in a dynamic sense, haem-iron doming must be the first conformational change to occur following ligand dissociation. Here we present the first direct demonstration that haem-iron doming occurs on the same time scale as the breaking of the iron-ligand bond, thus establishing haem-iron doming as the primary event which lead to the R-->T transition in haemoglobin. 相似文献