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A study was undertaken to assess the health, nutrition and psychosocial profile of Institutionalized children in four States--Uttar Pradesh, Andhra Pradesh, Karnataka and West Bengal. A sample of 3,822 children from 70 institutions in 6-18 years age group formed the subjects of the study. It was observed that the destitute children were mainly taken care of in three types of institutions, viz, Voluntary, Government Aided and Government run institutions. Calorie deficiency and deficiency of Vitamins and minerals characterized the diets of these children. In general, there was no deficit of protein in their diets. Growth wise, these children were retarded both in height and weight compared to standards. However, they fared better in comparison to their age and sex counterparts in the rural and urban poor. Psychosocial profile of these children indicated that the prevailing environment in the institutions is less conducive for intellectual stimulation but not so for the development of skills of self-help, locomotion, socialization and imagery.  相似文献   
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We have previously hypothesized that an effective vaccine against HIV should elicit cell-mediated immunity without antiviral antibody production. As a first step towards this goal we have identified potential T-cell epitopes, without B-cell activity against the native protein, from the first and second conserved sequences, and from three functionally important regions of the HIV-1 envelope protein gp160. For this approach, short peptide sequences selected by established computer programs were synthesized and chemically modified to generate either polymers with disulfide bonds, or micelles with two palmitic acid residues attached to the amino-terminal lysine. In both configurations several peptides were immunogenic without the need for coupling to carrier molecules. Of the 19 peptides we tested in our present studies, seven induced good T-cell proliferative response in mice representing four major histocompatibility complex haplotypes. None of these seven peptides produced antibodies that could recognize the envelope protein gp160.  相似文献   
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P-glycoprotein, a 170-kd glycoprotein encoded by theMDR 1 gene, is a member of a highly conserved superfamily of ATP-binding cassette (ABC) transport proteins. It shares extensive homology with numerous bacterial and eukaryotic ABC transport proteins. P-glycoprotein acts as an energy-dependent efflux pump that appears to transport structurally diverse agents ranging from ions to peptides. P-glycoprotein (P-gP) has been implicated as playing a role in multidrug (MDR) resistance in cancer, chloroquine-resistantPlasmodium falciparum infection, and possibly human immunodeficiency virus-1 (HIV-1) resistance to nucleoside compounds. A number of normal tissues in humans and rodents have been shown to express high levels of P-gp. The expression and function of P-gp in cells of the immune system have been explored in the past 2 years. This review presents a state of the art regarding the expression, regulation, and function of Pgp in cells of the immune system. In addition, its alteration in aging and HIV-1 infection is reviewed. A possible physiologic role of P-gp in cytokine secretion, antigen processing/presentation, and effector functions is also discussed.  相似文献   
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The Pseudomonas aeruginosa PAK pilus is capable of mediating the binding of this strain to human respiratory epithelial cells. We have produced monoclonal antibodies (MAbs) to the PAK pilus in order to elucidate the location of the binding domain of the pilus for human buccal epithelial cells (BECs). Four MAbs are described. MAbs PK41C and PK34C were found to react with P. aeruginosa pilins produced by a large number of strains. The epitope recognized by PK41C was determined to lie within the N-terminal region of the pilin and is likely constituted by amino acid residues 22 through 33. The epitope for PK34C was located in the C-terminal region of the pilin and was partially dependent on an intact intrachain disulfide bridge between cysteine residues 129 and 142. PK99H and PK3B were found to react specifically with PAK pilin. The epitope for PK99H was also localized in the C-terminal region of the pilin protein and appears to reside between amino acid residues 130 and 138. The epitope for PK3B was not localized by using the methods of this study, but it is likely dependent on the three-dimensional structure of the pilin. Fab fragments of PK99H inhibited adhesion of strains PAK and 492c to BECs, but the adherence of five other strains was not affected. Fab fragments of PK34C inhibited adhesion of all piliated strains examined. Fab fragments from both of these antibodies inhibited PAK pilus binding to BECs. Fab fragments of PK41C and PK3B had no effect on P. aeruginosa binding to BECs. These results confirm that the C-terminal region of the pilin has adhesin qualities and that a conserved epitope lies within this region.  相似文献   
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Hepatic veno-occlusive disease (VOD) is the second most common cause of death after autologous bone marrow transplantation (ABMT). A patient with multiple myeloma undergoing ABMT developed classic features of hepatic VOD. He responded to treatment with pentoxiphyllin. Serum tumor necrosis factor (TNF) levels showed remarkable correlation with the severity of VOD and response to therapy.  相似文献   
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AIMS: To estimate the incidence of active tuberculosis (TB) and study the use of chemoprophylaxis for latent TB in children in Wales, and to identify potential areas for improving prevention and management. METHODS: Active surveillance for TB in children aged 0-15 years from July 1996 to December 2003, using the Welsh Paediatric Surveillance Scheme. RESULTS: A total of 232 children, 102 with active TB (2.3 per 100 000) and 130 with latent TB (2.9 per 100 000), were identified. Nearly half (45%) belonged to ethnic minorities (19% were of black African origin), a much higher proportion than the base population. Pulmonary disease was the most common presentation (47%), including six (9%) children who were sputum smear positive. There were 10 cases of disseminated TB, nearly all in white children under 10 years of age. Less than two thirds of eligible children (27/46, 59%) were known to have received BCG immunisation. The source of infection was an adult household contact in most cases, but was not known in 44 cases, particularly among teenagers. Four community outbreaks occurred during the surveillance period, including three in high schools. CONCLUSION: TB incidence in children in Wales remains low, but the epidemiology is changing with an increasing proportion of cases in black African children. The high proportion of patients with disseminated TB is of particular concern. TB in teenagers was often associated with school outbreaks. Many eligible children do not receive BCG immunisation, indicating further scope for prevention.  相似文献   
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