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1.
Decline in human immunodeficiency virus seropositivity and seroconversion in US Navy enlisted personnel: 1986 to 1989. Navy HIV Working Group.
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F C Garland E D Gorham S O Cunnion M R Miller L L Balazs 《American journal of public health》1992,82(4):581-584
The US Navy administered 1,795,578 enzyme-linked immunosorbent assay (ELISA) tests to 848,632 active-duty Navy enlisted personnel during 1986 to 1989. This study identified 2438 human immunodeficiency virus (HIV)-seropositive active-duty enlisted Navy personnel, including 778 seroconverters. Three types of quarterly rates of HIV seropositivity and seroconversion were determined. All three rates declined. This decline could not be explained by changes in the population tested according to age, race, sex, occupation, or geographic location of home port. 相似文献
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The evolution of a biodegradable membrane for use in urological surgery. A summary of 109 in vivo experiments 总被引:3,自引:0,他引:3
R Scott R Mohammed S D Gorham D A French M J Monsour A Shivas T Hyland 《British journal of urology》1988,62(1):26-31
The evolution of a collagen/vicryl composite membrane designed as a prosthetic material for use in urinary tract surgery is described. The early experiments in which collagen film alone was used to repair experimental ureterotomies are reviewed together with our first experiments with the collagen/vicryl prosthesis in the repair of partial nephrectomies and of full thickness defects created in the urinary bladder of experimental rabbits. These early results led to the preparation of a composite using a more highly purified collagen and employing a method of sterilisation (gamma irradiation) which would be acceptable for regular use in medical products. The results of a further series of partial nephrectomy and full thickness bladder repairs show that irradiation does not compromise the efficacy of the collagen/vicryl composite in vivo. 相似文献
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Jacquie A Shillis Beverly A Hall Gail G Sneden Nell H Gottlieb 《Health education & behavior》2003,30(6):771-788
This case study examines a nonlegislative task force as it struggled to reach internal consensus despite external political constraints. The study highlights the convergence of politics and science, revealing complex issues likely to be confronted by advocates and public health officials. Three themes capture participants' experiences: context, sizing up the opportunities and constraints; task force process, tacit strategy to operate outside the political context and play the science card; and aftermath, a glass half full. The task force took advantage of ambiguous parameters, crafting a comprehensive statewide plan to reduce tobacco use and breaking out of the common public health paradigm of allowing budget considerations to drive program design. These internal victories could not sustain a policy success in the legislature. However, the group's product sets science-based standards for future program development, and the task force's process provides valuable insights into other states developing tobacco prevention and control policies. 相似文献
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Macrophages in immunity to syphilis: suppressive effect of concurrent infection with Mycobacterium bovis BCG on the development of syphilitic lesions and growth of Treponema pallidum in tuberculin-positive rabbits.
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Paired groups of male rabbits were challenged with Treponema pallidum and Mycobacterium bovis BCG. One group had been sensitized to BCG by inoculation 3 weeks before challenge. All animals were challenged intradermally at multiple sites with T. pallidum alone, BCG alone, and both organisms into the same sites. The resulting lesions were followed clinically and histologically. BCG lesions enlarged more rapidly in sensitized rabbits, but they were otherwise no different from those in the controls. T. pallidum lesions enlarged and regressed simultaneously in both groups, but in the BCG-sensitized animals they became twice as large as those in the unsensitized rabbits. Mixed BCG-T. pallidum lesions showed the greatest differences in the two groups of animals. Like the pure BCG lesions, they enlarged more rapidly in the sensitized rabbits but began to recede after 1 week. The corresponding lesions in the controls enlarged more slowly and reached their maximum size after 3 weeks when the receding lesions in the sensitized animals were much smaller. The most marked histological-histochemical difference between the two groups of animals was in the number and activation of macrophages. These cells were more numerous in the mixed lesions of BCG-sensitized animals than in similar lesions of the controls and more activated as determined by beta-galactosidase staining. Although sparsely distributed, activated macrophages were more numerous in the pur T. pallidum lesions of sensitized animals than in those of control animals. Silver-stained sections revealed fewer treponemes in mixed lesions of sensitized animals than in the mixed lesions of control animals. Quantitation of treponemes in pure T. pallidum versus mixed lesions was determined in two groups of rabbits challenged intratesticularly. The total number of treponemes per testis in the mixed lesions of BCG-sensitized rabbits was significantly less than the number in the mixed lesions of control animals, and also less than the number in pure T. pallidum lesions of both groups of animals. 相似文献
7.
Isolation and Purification of Treponema pallidum from Syphilitic Lesions in Rabbits 总被引:1,自引:5,他引:1
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Treponema pallidum were extracted from testicular syphilomas of corticosteroid-treated rabbits and purified by differential centrifugation. The steroid therapy allowed a longer holding time for infected rabbits, which produced greater treponeme yields, averaging 1.58 × 1010 treponemes per rabbit. The treatment, which also diminished cellular infiltration and increased the extracellular mucoid material in lesions, produced much cleaner suspensions than preparations from nontreated animals. Most of the treponemes in the purified suspensions were still motile, and none carried demonstrable host immunoglobulin. The preparations were free of recognizable host tissue debris and they contained, on the average, 1.9 × 10−7 μg of protein per treponeme. 相似文献
8.
Summary Monoclonal antibodies (MAbs) and polyclonal immune sera were produced and used to identify the major antigens of bovine herpesvirus type 4 (BHV-4). SDS-polyacrylamide gel electrophoresis of immunoprecipitates of radiolabeled lysates from infected cells resolved 24 peptide bands varying from 12kDa to over 300kDa. Six peptides were identified as major viral antigens by immunoprecipitation. Based on the pattern of radioimmunoprecipitation, MAbs were assigned into four groups. Group 1 precipitated a tunicamycinsensitive glycoprotein complex which contained six components (245, 190, 152, 123, and 48/46kDa). Deglycosylation with endoglycosidase F revealed two peptides with Mr of 93 and 38kDa as the basic peptides of the glycoprotein complex. In addition, a 115kDa glycopeptide containing glycan-peptide bonds of mixed type was identified. Group 2 precipitated a non-glycosylated protein complex consisting of three monomers (33/31/30kDa). Groups 3 and 4 reacted with single monomeric non-glycosylated peptides with Mr of 48 and 14kDa, respectively. Although none of the MAbs exhibited significant neutralizing activity, some reacted strongly in immunosorbent and/or immunohistochemical assays, suggesting they may be good candidates for use in diagnostic assays. 相似文献
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