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1.
Studies of HIV prevention interventions such as pre-exposure prophylaxis (PREP) and circumcision in India are limited. The present study sought to investigate Indian truck-drivers initial commitment to PREP and circumcision utilizing the AIDS Risk Reduction Model. Ninety truck-drivers completed an in-depth qualitative interview and provided a blood sample for HIV and HSV-2 testing. Truck-drivers exhibited low levels of initial commitment towards PREP and even lower for circumcision. However, potential leverage points for increasing commitment were realized in fear of infecting family rather than self, self-perceptions of risk, and for PREP focusing on cultural beliefs towards medication and physicians. Cost was a major barrier to both HIV prevention interventions. Despite these barriers, our findings suggest that the ARRM may be useful in identifying several leverage points that may be used by peers, health care providers and public health field workers to enhance initial commitment to novel HIV prevention interventions in India.  相似文献   
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Yamuna Narayanan 《Genetics》1973,73(2):319-350
The phylogenetic relationships among the species of the D. robusta group were investigated by the analysis of chromosomal differences. Six of the ten known members of the D. robusta group were available for the study: D. colorata and D. robusta from the United States, and D. sordidula, D. pseudosordidula, D. lacertosa, and D. moriwakii from Japan. Analysis of the metaphase chromosomes from larval ganglion cells suggests that D. moriwakii and D. colorata, with rod-shaped X-chromosomes, are the more ancestral species, while D. sordidula, D. pseudosordidula, D. robusta, and D. lacertosa, with V-shaped X-chromosomes, are derived. The ancestral position of D. colorata and D. moriwakii is further strengthened by the fact that these are the two species in the D. robusta group that are cytologically closest to D. nigromelanica of the related D. melanica group. Of the four derived species, D. sordidula was found to be the closest to the ancestral species. The phylogeny based on the analysis of the gene sequences in the homologous chromosomes agreed with that indicated by the metaphase chromosomes. Since all attempts to obtain hybrids were unsuccessful except for the cross involving D. moriwakii females and D. colorata males, photographic maps of the salivary chromosomes were used to determine homology between the chromosomes of the different species. Evidence is presented to indicate that the D. robusta group originated in Asia (Japan), and that there were two migrations to the New World, the first leading to D. robusta, and the second to D. colorata. It is suggested that the route of migrations was across the Bering Land Bridge, and further, that the migrations occurred during the period from late Oligocene to middle Miocene, 20-25 million years ago.  相似文献   
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Replication control genes of plasmid pE194.   总被引:28,自引:17,他引:11       下载免费PDF全文
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A method has been developed for immobilisation of antisera on fresh plastic tubes through an immunochemical bridge. This type of immobilisation has been shown to be more consistent than direct adsorption on plastic. Such immunochemically coated antisera on plastic tube has been used in the development of a noncentrifugation radioimmunoassay. This assay system has been found to be technically as sound as the conventional method.  相似文献   
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In the present study, the effects of the cytosolic Ca2+ transport inhibitor on ATP-dependent Ca2+ uptake by, and unidirectional passive Ca2+ release from, sarcoplasmic reticulum enriched membrane vesicles were examined in parallel experiments to determine whether inhibitor-mediated enhancement in Ca2+ efflux contributes to inhibition of net Ca2+ uptake. When assays were performed at pH 6.8 in the presence of oxalate, low concentrations (less than 100 micrograms/mL) of the inhibitor caused substantial inhibition of Ca2+ uptake by SR (28-50%). At this pH, low concentrations of the inhibitor did not cause enhancement of passive Ca2+ release from actively Ca2+-loaded sarcoplasmic reticulum. Under these conditions, high concentrations (greater than 100 micrograms/mL) of the inhibitor caused stimulation of passive Ca2+ release but to a much lesser extent when compared with the extent of inhibition of active Ca2+ uptake (i.e., twofold greater inhibition of Ca2+ uptake than stimulation of Ca2+ release). When Ca2+ uptake and release assays were carried out at pH 7.4, the Ca2+ release promoting action of the inhibitor became more pronounced, such that the magnitude of enhancement in Ca2+ release at varying concentrations of the inhibitor (20-200 micrograms/mL) was not markedly different from the magnitude of inhibition of Ca2+ uptake. In the absence of oxalate in the assay medium, inhibition of Ca2+ uptake was observed at alkaline but not acidic pH.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
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Effects of lithium in vivo and in vitro on the two molecular forms of Na+,K(+)-ATPase in rat brain were investigated. Inhibition by strophanthidin, affinity to monovalent cations and cellular localization of the enzyme were used to differentiate the two molecular forms. K+ dependent p-nitrophenylphosphatase activity and strophanthidin inhibition studies revealed selective increase in the activity of low affinity form but not high affinity form of the enzyme following lithium treatment. Na+ sensitivity of neither forms of Na+,K(+)-ATPase was changed but K+ sensitivity of low affinity form was increased due to lithium. Lithium showed biphasic effects on low affinity form of the enzyme; activation at low concentration and inhibition at high concentration. The results suggest that lithium in vivo regulates the concentration of extra cellular potassium by selectively acting at K+ site of low affinity form of the enzyme (astroglial) but not on high affinity form (neuronal enzyme) and leading to changes in neuronal depolarization.  相似文献   
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Skin-flap ischemia has been associated with the presence of free radicals. In this study, two enzyme systems involved in free-radical metabolism were used to compare a distal skin flap to a skin graft. Forty-two rats were divided into several test groups. A 10 X 3 cm dorsal rat flap was used, and tissue biopsies for xanthine oxidase and malonyldialdehyde (MDA) were obtained 2.5, 5.5, and 8.5 cm from the base of the flap at the hours given. In group I (control), the flap was outlined but not elevated, and biopsies were obtained. In group II, the flap was elevated, and biopsies were obtained at 6 hours. In group III, the flap was elevated, the distal 4 X 3 cm was amputated and replaced as a full-thickness skin graft, and biopsies were obtained at 6 hours. In group IV, the flap was elevated, and biopsies were obtained at 12 hours. In group V, the flap was treated as in group III, and biopsies were obtained at 12 hours. In group VI, the flap was elevated, and biopsies were obtained at 24 hours. In group VII, the flap was treated as in group III, and biopsies were obtained at 24 hours. Results: Xanthine oxidase was significantly higher in all distal biopsies compared to proximal biopsies. Xanthine oxidase also increased with time. Malonyldialdehyde increased over time as well as with distance from the flap base. Distal flap biopsies at 24 hours had greatly increased levels of malonyldialdehyde compared to skin grafts (p less than 0.001).(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
10.
Pt(IV)(dach)Cl4 (dach = cyclohexyldiamine) was reacted with guanosine and 9-methylguanine and their reaction products were analyzed by single-crystal x-ray diffraction. In both cases the resulting complexes, [Pt(dach)(guanosine)2]2+ and [Pt(dach)(9-methylguanine)2]2+ respectively, corresponded to an unanticipated reduction of the octahedral Pt(IV) starting material to a square planar Pt(II) species. The nature of the reducing agent is presently unknown.  相似文献   
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