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排序方式: 共有1517条查询结果,搜索用时 15 毫秒
1.
John A. Schneider Rakhi Dandona Shravani Pasupneti Vemu Lakshmi Chuanhong Liao Vijay Yeldandi Kenneth H. Mayer 《PloS one》2010,5(7)
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
2.
3.
Dsi-1, a region with frequent proviral insertions in Moloney murine leukemia virus-induced rat thymomas. 总被引:9,自引:5,他引:4
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Dsi-1 is a region of chromosomal DNA that underwent proviral insertion in 3 of 24 Moloney murine leukemia virus-induced rat thymomas. In one of these tumors, a provirus is also integrated adjacent to the proto-oncogene c-myc. The proviruses in Dsi-1 have been characterized and appear to be complete. The proviruses were located within a 2-kilobase region that contained four prominent DNase I-hypersensitive sites. These hypersensitive sites were observed in Moloney murine leukemia virus-induced thymomas but not in NRK cells. The region of Dsi-1 immediately 3' to the insertions cross-hybridized with human and chicken DNA, indicating that it contains highly conserved sequences. No evidence could be found for the expression of this highly conserved region. Dsi-1 was mapped to mouse chromosome 4. This location demonstrates that Dsi-1 is different from 16 of the known proto-oncogenes (c-abl, c-erbA c-erbB, c-ets-1, c-ets-2, c-fes, c-fos, c-myb, c-myc, c-raf, A-raf, c-Ha-ras, c-Ki-ras, N-ras, c-sis, and c-src) and 12 cellular regions of tumor-associated integrations in retrovirus-induced tumors (c-erbB, Fis-1, int-1, int-2, Mis-1/pvt-1, Mlvi-1, Mlvi-2, c-mos, c-myb, c-myc, Pim-1, and c-Ha-ras). Hybridization experiments indicated that Dsi-1 is probably different from five additional proto-oncogenes (c-fgr, c-fms, c-mos, neu, and c-yes) and from two additional frequent integration regions (lck and Mlvi-3). 相似文献
4.
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
5.
G Y Lakshmi 《Indian journal of experimental biology》1989,27(10):903-906
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
6.
Transport to the cell surface of a peptide sequence attached to the truncated C terminus of an N-terminally anchored integral membrane protein. 总被引:5,自引:0,他引:5
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Attempts to construct hybrid proteins that are transported to the plasma membrane are frequently unsuccessful because of perturbations in polypeptide folding. In seeking to minimize this problem, we have used the less common type of integral membrane protein, which has an uncleaved signal-anchor domain and an extracellular carboxyl portion, to transport a peptide sequence of interest to the cell surface. A set of plasmids was constructed that contained the gene encoding respiratory syncytial virus glycoprotein G (RSVG) interrupted immediately after one of several proline codons by a synthetic sequence containing unique restriction endonuclease sites and a stop codon. The shortened RSVG gene was flanked by vaccinia virus DNA to permit cloning and expression in a vaccinia virus vector. An open reading frame encoding four copies of the immunodominant repeating epitope of the circumsporozoite protein of Plasmodium falciparum was inserted into the tails of the truncated RSVG genes. Recombinant vaccinia viruses were isolated and shown to express hybrid proteins that reacted with a monoclonal antibody directed to the repeating circumsporozoite epitope. Moreover, immunofluorescence studies indicated that the peptide was on the external cell surface and available to react with antibodies. Expression of the hybrid protein also occurred in rabbits inoculated with the live recombinant vaccinia virus, as demonstrated by the generation of antibodies that bound to P. falciparum sporozoites in vitro. 相似文献
7.
Krishnan V 《Social biology》1991,388(3-4):249-257
This paper examines a number of demographic and sociocultural factors (e.g., age, marital status, family size, religion, religious assiduity, sex-role ideology) as predictors of women's attitudes toward abortion, using data from the Canadian Fertility Survey of 1984. The findings suggest that women's abortion attitudes are to a greater extent based on ideological positions. It appears that anti-abortion stance affects those women who are religious, presumably by increasing the relationship between their general sex-role ideological stances and abortion attitudes. Abortion attitudes also vary according to a woman's education, her size, and province/region of residence. 相似文献
8.
Lionel Sibold Dominique Pariot Lakshmi Bhatnagar Marc Henriquet Jean-Paul Aubert 《Molecular & general genetics : MGG》1985,200(1):40-46
Summary Using the Southern hybridization technique, homologies were examined between restricted DNA of four methanogenic bacteria (Methanobacterium ivanovi, Methanobacterium thermoautotrophicum, Methanococcus voltae, Methanosarcina barkeri) and the nif (nitrogen fixation) genes of Klebsiella pneumoniae and Anabaena strain 7120. With K. pneumoniae probes, no hybridization was observed with nifA, nifNE, and nifJ but positive results were obtained with the nifHDK genes coding for nitrogenase. Homology was detected, in the four strains, with K. pneumoniae and Anabaena nifH probes. In M. voltae and M. ivanovi, the homology found with nifH was estimated to be about 70% and a weaker hybridization was observed also with nifD and nifK. In M. voltae, the sequence homologous to nifH was found on a 3.0 kbp HindIII fragment and sequences homologous to nifD and nifK on a 3.8 kbp HindIII fragment. The 3.0 kbp fragment was cloned and the region homologous to nifH was localized more precisely. When this fragment was used as a probe against other DNAs, it behaved as a K. pneumoniae and Anabaena nifH probe. The results suggest that the structural genes for nitrogenase may be present in archaebacteria and raise interesting questions regarding their evolution. 相似文献
9.
Summary A major portion of the genomes of three millet species, namely, barn yard millet, fox tail millet and little millet has been shown to consist of interspersed repeat and single copy DNA sequences. The interspersed repetitive DNA sequences are both short (0.15–1.0 kilo base pairs, 62–64% and long (>1.5 kilo base pairs, 36–38%) in barn yard millet and little millet while in fox tail millet, only long interspersed repeats (>1.5 kilo base pairs) are present. The length of the interspersed single copy DNA sequences varies in the range of 1.6–2.6 kilo base pairs in all the three species. The repetitive duplexes isolated after renaturation of 1.5 kilo base pairs and 20 kilo base pairs long DNA fragments exhibit a high thermal stability with Tms either equal to or greater than the corresponding native DNAs. The S1 nuclease resistant repetitive DNA duplexes also are thermally stable and reveal the presence of only 1–2% sequence divergence.The present data on the modes of sequence arrangement in millets substantiates the proposed trend in plants, namely, plants with 1C nuclear DNA content of less than 5 picograms have diverse patterns of sequence organization while those with 1C nuclear DNA content greater than 5 picograms have predominantly a short period interspersion pattern.Abbreviations kbp
kilobase pairs
NCL Communication No. 3606. 相似文献
10.
Summary A mixed culture of Endomycopsis fibuligera NRRL 76 and Zymomonas mobilis ZM4 could directly and more efficiently ferment cassava starch (22.5% w/v) to ethanol (10.5% v/v) than the monocultures. The combination of culture filtrate of E.fibuligera containing amylases and Z.mobilis simultaneously saccharified and fermented the cassava starch to ethanol equally well. Glucoamylase (0.01%) added to the fermenting medium improved ethanol (13.2% v/v) production by the above mixed culture to almost the theoretical level (98%) indicating that this enzyme is a rate-limiting factor in E.fibuligera. Z. mobilis alone converted the enzymehydrolyzed starch only to almost theoretical level (98%). 相似文献