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81.
We compared the performances of the Third Wave Technology Invader method and the Digene Hybrid Capture 2 assay to detect high-risk human papillomaviruses in 87 cervical brushing specimens submitted in Cytyc ThinPrep media. Two different methods for the extraction of DNA from squamous epithelial cells were also evaluated.  相似文献   
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Immunochemical Characterization of a Human Antibody to Factor XIII   总被引:1,自引:0,他引:1  
Dispersed and intact marrow fragmentshave been implanted in the omentum andsubcutaneous fat of irradiated and nonirradiated hosts. Osteogenesis and hemopoiesis in varying proportions wereobserved at 10 and 35 days. The subcutaneous site favored osteogenesis, theomental site and host irradiation prior totransplant resulted in predominance ofhemopoiesis. In dispersed and recompacted marrow grafts, only hemopoiesisdeveloped. Differentiation was predominantly granulocytic. Osteogenesis is notan obligatory prerequisite of hemopoiesisin extramedullary sites.

Submitted on January 31, 1973 Revised on April 23, 1973 Accepted on April 25, 1973  相似文献   
86.
Dichloroacetate activates the pyruvate dehydrogenase complex of many tissues by inhibiting the kinase responsible for phosphorylation and inactivation of the complex. Dichloroacetate also activates the myocardial branched-chain α-keto acid dehydrogenase complex but apparently not by direct inhibition of the analogous kinase. Oxalate and glyoxylate, metabolites of dichloroacetate, are responsible for some in vitro effects of dichloroacetate. Dichloroacetate stimulates leucine oxidation by isolated hepatocytes because glyoxylate transaminates with leucine. Dichloroacetate inhibits lactate gluconeogenesis by hepatocytes incubated in low bicarbonate buffer because oxalate inhibits pyruvate carboxylase under such conditions. In vivo, dichloroacetate decreases blood glucose by limiting the supply of gluconeogenic precursors to the liver. This effect is a consequence of pyruvate dehydrogenase activation in peripheral tissues. Dichloroacetate lowers blood cholesterol in hyperlipidemic patients by uncertain means. Dichloroacetate has been tried experimentally in treatment of diabetes, hypercholesterolemia, and hyperlactatemia, but it has neurotoxicity, can cause cataracts, and may be mutagenic.  相似文献   
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Evidence for Boundary Lipid in Membranes   总被引:13,自引:18,他引:13       下载免费PDF全文
Cytochrome oxidase (EC 1.9.3.1) isolated from beef-heart mitochondria with an appropriate phospholipid content forms vesicular structures. Lipid-protein interactions in this model membrane system were studied with the lipid spin label, 16-doxylstearic acid. As the phospholipid/protein ratio is varied, two spectral components are observed. At low phospholipid/protein ratios (相似文献   
88.
Lymphocytes from a patient with severe combined immunodeficiency (SCID) of the X-linked adenosine deaminase-positive type were studied in detail. Eighty per cent of peripheral blood cells were positive for surface immunoglobulins, the predominant fluorescence being immunoglobulin G (IgG). Double-labeling experiments showed 30 per cent of cells to be positive for γ and μ; all μ-staining cells also had γ. Few δ-positive cells were found. Both the γ- and μ-bearing cells contained either κ and λ light chains, the ratio of κ to λ being 4:1. These high percentages of immunoglobulin-bearing cells are in contrast to the very low or absent serum immunoglobulin concentrations and suggest failure of differentiation into actively-secreting lymphocytes or plasma cells. No evidence for circulating suppressor cells was found. An unusual subpopulation of B cells, previously termed B2, predominated in that complement receptors C3b and C3d were absent by EAC and Raji technics.Thymus-derived lymphocytes were absent in this patient, and T-cell functions were severely impaired as measured by skin test anergy, and mitogen and allogeneic responses in vitro. An increased tridiated thymidine (3H-TdR) incorporation and a normal percentage of cells entering interploid S phase and tetraploid G2 and M phase of the cell cycle (S-G2-M) (by cytofluorographic analysis) followed the incubation of lymphocytes with calcium ionophore A23187. These membrane findings suggest possible pathogenetic mechanisms for the deficiencies in patients with this specific subset of SCID disease. The absence of a putative endogenous membrane ionophore, a defect in cytoskeleton, for example, a defect in microtubules or microfilaments, or impaired intracellular cyclic nucleotide activation or distribution, or defects in protein phosphorylation or sialation could all explain these observations.  相似文献   
89.
A family consisting of eight members in three generations (age 10 months to 53 years) affected with chronic mucocutaneous candidiasis was studied along with three unaffected relatives. Dermatophytosis, loss of teeth and recurrent viral infections were present in some members. Results of tests for endocrinologic, muscle or liver disease, thymoma, iron deficiency, antitissue antibodies and malabsorption were normal in all patients. Antibody function and levels, B cell counts, serum complement, leukocyte enzymes, chemotaxis, phagocytosis and adherence were normal in all members. Plasma inhibitors to lymphocyte transformation and leukocyte inhibitory factor were not found. No unique HLA haplotype or antigen segregated in this family. Evaluation of cell-mediated immunity revealed total cutaneous anergy in three of eight whereas four of the other five had negative lymphocyte transformation and skin tests to Candida but responded normally to other antigens. Leukocyte inhibitory factor was not produced to Candida antigen in all four patients tested. T cell counts were within normal limits in all. Extensive evaluation of all limbs of the immune system in this family revealed a defect in cell-mediated immunity to Candida that appeared to be inherited as a dominant characteristic.  相似文献   
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