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41.
We identified a 685-nucleotide gene fragment that codes for the transmembrane and cytoplasmic domains of glycoprotein of the LEP strain rabies virus and carried out experiments designed to express a novel fusion protein on the cell surface. The cDNA encoding the membrane anchor sequence was fused in the correct reading frame to the 3' end of the cDNA encoding the beta subunit of human chorionic gonadotropin (beta(h)CG), a secretory glycoprotein that is used as an antigen for a contraceptive vaccine being developed in our laboratory. The fusion gene cassette was placed under the control of a vaccinia virus early promoter and cloned in a host-restricted fowlpox viral vector. The recombinants, when used to infect mammalian cells that do not allow the replication of fowlpox virus, expressed the N-terminal 135 amino acid residues of beta(h)CG anchored in the cell membrane by the 75-amino acid C-terminal sequence derived from rabies virus glycoprotein. This hybrid protein is correctly processed post-translationally and transported efficiently to the plasma membrane of non-permissive cells such that the anchored beta(h)CG molecule retains the correctly folded native antigenic epitope(s).  相似文献   
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From epithelial layer of rat intestinal were selected water soluble substances which influenced on Na+,K(+)-ATPase activity in 2 different ways: substances with molecular weight 220 Da, 400 Da were its activators, substance with weight 150 Da-inhibitor. Na+,K(+)-ATPase activators preincubated previously with Na+ acquire properties of inhibitors. Bivalent cations Ca, Mg remove this effect of Na-ions.  相似文献   
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Physicians for Human Rights/Denmark visited Kashmir three times in 1993 and 1994. In Indian-held Kashmir we examined victims of torture and gunshots and we assessed similar evidence collected by local lawyers and doctors. In refugee camps for Indian Kashmiries we examined ten children, who were reported to have been tortured at the age of 5-14 years, and ten other children who allegedly had been ill-treated. Furthermore, 17 adults, who reported that they had been tortured, were examined. In nearly all cases there were physical findings in accordance with the histories of torture. In many cases, including those of the children, the findings were highly remarkable by their shape and localization. We interpret them as evidence of intentionally inflicted injuries. In the refugee camps we carried out a prevalence study of exposure to organized violence. Approximately 95% of all families had been exposed to violence; 35% reported that their children had been ill-treated. The physical findings indicate that intentional traumatization of civilians including children in Indian-held Kashmir takes place; the results of the prevalence study suggest that exposure to violence is widespread.  相似文献   
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Kaposi's sarcoma (KS) is a malignancy suspected of having an infectious etiology. Unique viral DNA sequences were recognized in KS lesions, using a novel technique that identifies small differences between two complex genomes. The virus had homology with the herpesvirus family, especially Epstein Barr virus (EBV), yet it was distinct from the known herpesviridae, and was appropriately named human herpesvirus 8 (HHV-8) or Kaposi's sarcoma-associated herpesvirus (KSHV). HHV-8 DNA sequences were present in AIDS-associated KS, classic KS, African endemic KS, Mediterranean KS, iatrogenic KS, and KS in homosexual men without HIV infection. HHV-8 DNA sequences were also present in peripheral blood mononuclear cells (PBMC) of KS+ patients; body-cavity-based lymphomas in HIV positive patients without KS; and in tissue from a number of malignant and non-malignant lesions in patients without HIV infection. The role of HHV-8 in KS and other malignancies is not known. Viruses are notoriously trophic for lesional tissue. Therefore, in order to determine the role of HHV-8 in KS pathogenesis, HHV-8 needs to be isolated and shown to induce immortalization in a suitable system. Regardless of its role in KS, another human herpesvirus has been discovered, and the extent of its pathogenicity needs to be uncovered.  相似文献   
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The authors present their experience gained in the training of ophthalmologists at the Chair of Ocular Diseases of the Krasnoyarsk Medical Institute. In 1991 the interns, instead of traditional state examinations, maintained their diploma research, which was assessed as their skills and knowledge in the field of ocular diseases, social hygiene, and public health organization. The authors prove that such diploma research is an integral part of undergraduate training and one of the types of individual work at higher educational institutions, and enumerate the topics of diploma research.  相似文献   
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NMR (1H and 31P) and HPLC techniques were used to study the partitioning of phosphoramide mustard (PM) and its aziridinium ions among alkylation and P-N bond hydrolysis reactions as a function of the concentration and strength of added nucleophiles at 37 degrees C and pH 7.4. With water as the nucleophile, bisalkylation accounted for only 10-13% of the product distribution given by PM. The remainder of the products resulted from P-N bond hydrolysis reactions. With 50 mM thiosulfate or 55-110 mM glutathione (GSH), bisalkylation by a strong nucleophile increased to 55-76%. The rest of the PM was lost to either HOH alkylation or P-N bond hydrolysis reactions. Strong experimental and theoretical evidence was obtained to support the hypothesis that the P-N bond scission observed at neutral pH does not occur in the parent PM to produce nornitrogen mustard; rather it is an aziridinium ion derived from PM which undergoes P-N bond hydrolysis to give chloroethylaziridine. In every buffer studied (bis-Tris, lutidine, triethanolamine, and Tris), the decomposition of PM (with and without GSH) gave rise to 31P NMR signals which could not be attributed to products of HOH or GSH alkylation or P-N bond hydrolysis. The intensities of these unidentified signals were dependent on the concentration of buffer.  相似文献   
49.
We report the occurrence of a relapsing, severe predominantly motor neuropathy in a 75-year-old man with an IGM-K M-protein binding to gangliosides GM2, GM3, GM4, GD1a, GT1b and LM1. Motor nerve conduction velocities were slowed with conduction block. A superficial peroneal nerve biopsy specimen revealed segmental demyelination and remyelination. The patient improved after repeated plasma exchanges, and the antibody titer decreased in association with clinical recovery. This IgM M-protein has a unique, previously unreported binding specificity for terminal NeuAcalpha2-3Galbeta- moiety in common to all gangliosides bound by the antibody except GM2. M-proteins with this affinity may be involved in the pathogenesis of this and other cases of motor-dominant demyelinating neuropathy.  相似文献   
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