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71.
Trevor A. Hart David M. Moore Syed W. Noor Nathan Lachowsky Daniel Grace Joseph Cox Shayna Skakoon-Sparling Jody Jollimore Abbie Parlette Allan Lal Herak Apelian Jordan M. Sang Darrell H. S. Tan Gilles Lambert the Engage Study Team 《Canadian journal of public health. Revue canadienne de santé publique》2021,112(6):1020
ObjectivesThe last Canadian biobehavioural surveillance study of HIV and other sexually transmitted and blood-borne infections (STBBI) among gay, bisexual and other men who have sex with men (GBM) was conducted in 2010. We designed a study to measure STBBI prevalence among GBM in metropolitan Montreal, Toronto and Vancouver and to document related preventive and risk behaviours.MethodsThe Engage Cohort Study used respondent-driven sampling (RDS) to recruit GBM who reported sex with another man in the past 6 months. At baseline, we examined recruitment characteristics of the samples, and the RDS-II-adjusted distributions of socio-demographics, laboratory-confirmed HIV and other STBBI prevalence, and related behaviours, with a focus on univariate differences among cities.ResultsA total of 2449 GBM were recruited from February 2017 to August 2019. HIV prevalence was lower in Montreal (14.2%) than in Toronto (22.2%) or Vancouver (20.4%). History of syphilis infection was similar across cities (14–16%). Vancouver had more HIV-negative/unknown participants who reported never being HIV tested (18.6%) than Toronto (12.9%) or Montreal (11.5%). Both Montreal (74.9%) and Vancouver (78.8%) had higher proportions of men who tested for another STBBI in the past 6 months than Toronto (67.4%). Vancouver had a higher proportion of men who used pre-exposure prophylaxis (PrEP) in the past 6 months (18.9%) than Toronto (11.1%) or Montreal (9.6%).ConclusionThe three largest cities of Canada differed in HIV prevalence, STBBI testing and PrEP use among GBM. Our findings also suggest the need for scale-up of both PrEP and STI testing among GBM in Canada. 相似文献
72.
In vitro cellular immune responses to recombinant antigens of Mycobacterium avium subsp. paratuberculosis
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Shin SJ Chang CF Chang CD McDonough SP Thompson B Yoo HS Chang YF 《Infection and immunity》2005,73(8):5074-5085
Five recombinant antigens (Ags; 85A, 85B, 85C, superoxide dismutase [SOD], and 35-kDa protein) were purified from Mycobacterium avium subsp. paratuberculosis and evaluated for their ability to stimulate peripheral blood mononuclear cells (PMBCs) from fecal-culture-positive cows (low and medium shedders) and culture-negative healthy cows. Recombinant Ags 85A, 85B, and 85C induced significant lymphocyte proliferation as well as the production of gamma interferon (IFN-gamma), interleukin-2 (IL-2), IL-12, and tumor necrosis factor alpha (TNF-alpha), but not IL-4, from low and medium shedders. The 85 antigen complex did not stimulate PMBC proliferation from culture-negative healthy cows. The 35-kDa protein also induced significant lymphocyte proliferation as well as the production of IFN-gamma and IL-4 from low and medium shedders. CD4(+) T cells and CD25(+) (IL-2R) T cells were stimulated the most by 85A and 85B, while the 35-kDa protein primarily stimulated CD21(+) B cells involved in humoral immune responses. Interestingly, SOD was less immunostimulatory than other antigens but strongly induced gammadelta(+) T cells, which are thought to be important in the early stages of infection, such as pathogen entry. These data provide important insight into how improved vaccines against mycobacterial infections might be constructed. 相似文献
73.
74.
Kim Sang Geon; Kedderis Gregory L.; Batra Renu; Novak Raymond F. 《Carcinogenesis》1993,14(8):1665-1670
Liver microsomal epoxide hydrolase (mEH) is active in the detoxificationof epoxide-containing carcinogens. The effects of thiazole andpyrazine, constituents of tobacco and tobacco smoke as wellas of a variety of foods, on the expression and regulation ofmEH were examined in rats (200 mg/kg body wt/day, i.p., 1/emdash3 days). Immunoblot analyses using rabbit anti-rat mEH antibodyrevealed a significant increase in mEH levels in hepatic microsomesisolated from either thiazole- or pyrazine-treated animals.Another protein (43 kd) cross-reacting with polyclonal mEH antibodywas found to be increased concomitantly following pyrazine treatment.Northern and slot blot analyses showed substantial increasesin mEH mRNA following either thiazole or pyrazine treatment.The level of mEH mRNA increased 17-fold at 24 h following thiazoletreatment, relative to control. Approximately 20- and 16-foldincreases in mEH mRNA were also observed at 48 and 72 h respectivelyfollowing treatment with pyrazine. The level of polymerase chainreaction (PCR)-amplified mEH DNA derived from poly(A)+ RNA wasclearly elevated following either thiazole or pyrazine treatmentrelative to that from untreated animals. Both sense and antisensestrands of PCR-amplified mEH DNA were cloned into an M13mpl9phage vector in order to examine the nucleotide sequences ofPCR-amplified mEH DNA derived from the poly(A)+ RNA isolatedfrom thiazole- or pyrazine-treated animals. Sequence analysesrevealed that the sequence of PCR-amplified DNA from the inducedmRNA was identical to that published for mEH cDNA. Epoxide hydrolaseactivity toward the hydrolysis of 2-cyanoethylene oxide (CEO),the epoxide metabolite of the rat carcinogen acrylonitrile,was not significant in hepatic microsomes from untreated rats,but was substantially induced by treatment with thiazole orpyrazine. Microsomal hydrolysis activity was heat-sensitiveand potently inhibited by l, l, l-trichloropropene-2, 3-oxide,indicating that mEH was the catalyst. The Vmax for the hydrolysisof CEO by hepatic microsomes from thiazole-treated rats (13.4nmol/min/mg protein) was 1.5-fold greater than that with microsomesfrom pyrazine-treated rats, whereas similar Km values ( 1 mM)were observed for both microsomal preparations. These kineticdata correlate well with the increases in mEH mRNA observedafter administration of thiazole or pyrazine to rats. Theseresults provide evidence that administration of thiazole orpyrazine induces mEH with a large increase in mEH mRNA, andthat the induced mEH catalyzes the hydrolysis of CEO. 相似文献
75.
蝶窦囊肿诊治47例分析 总被引:5,自引:1,他引:4
目的:提高对蝶窦囊肿的认识,以利于其诊断和治疗,方法:回顾性分析蝶窦囊肿47例,总结其发病趋势、临床表现,影像学特征及治疗效果。结果:蝶窦囊肿最主要的临床症状为头痛,约占64%;其次为眼部症状,再次为鼻部症状。蝶窦囊肿最易易及视神经,影响者视力,早期手术有利于神经力的恢复。鼻内窥镜下蝶窦囊肿摘除了术有损伤小,出血少,痛苦轻,手术时间短、安全,术后恢复快等优点。结论:CT、MRI和鼻内窥镜的应用,提 相似文献
76.
Second part of an item featuring action research with four different trusts to investigate factors relating to the implementation of the local pay policy. Describes methodologies used, such as clinical team diagnosis and cognitive mapping. Looks at the way forward, listing critical factors in ensuring successful implementation. 相似文献
77.
The NADH reductase component of the steroid 9α-hydroxylase fromMycobacterium fortuitum was purified to homogeneity. Recovery of the enzyme from the 50≈60% ammonium sulfate saturated fraction was 49%, with a purification
factor of 100-fold. The NADH reductase has a relative molecular mass of 60 KDa as determined by SDS-PAGE. The absorption maxima
at 410 and 450 nm indicate the presence of iron-sulfur group and flavin. These prosthetic groups seemed to function as redox
groups that transfer electrons from NADH to the following protein. The KM value for NADH as substrate was 68 μM. The NH2-terminal amino acid sequence of the reductase was determined as Met-Asp-Ala-Ile-Thr-Asn-Val-Pro-Leu-Pro-Ala-Asn-Glu-Pro-Val-His-Asp-Tyr-Ala-Thr.
This sequence does not show a homology with the NH2-terminal sequences reported for the reductase component of other monooxygenases, suggesting that the NADH reductase component
of the steroid 9α-hydroxylase system is novel. 相似文献
78.
A. Vallcanera Calatayud C. Sangüsa Nebot M. Martinez Fernandez H. Cortina Orts 《Pediatric radiology》1994,24(1):74-75
Severe unilateral varus deformity of the distal end of the femur secondary to a focal fibrous lesion is reported. It is a malformative process rare at this level, this being the first report of it in the radiological literature. The conventional radiograph is pathognomonic and CT is useful in the confirmation of the fibrous tissue. Osteotomy is indicated only if the deformity progresses or the angle of varus is severe. 相似文献
79.
Three 1,2-benzothiazine derivatives were synthesized, and their analgesic/anti-inflammatory efficacy and their effects on gastric irritation were evaluated. Among the three compounds, 39 exhibited the most potent analgesic action, but the effect was weaker than that of piroxicam. Nonetheless, the compound showed 4 times more potent analgesic action with less gastric damage than did ibuprofen. These compounds did not show anti-inflammatory effect at an oral dose of 5 mg/kg. 相似文献
80.
Cytotoxicity of urushiols isolated from sap of Korean lacquer tree (Rhus vernicifera stokes) 总被引:1,自引:0,他引:1
Hong DH Han SB Lee CW Park SH Jeon YJ Kim MJ Kwak SS Kim HM 《Archives of pharmacal research》1999,22(6):638-641
Cytotoxicities of four urushiols, congeners isolated from the sap of Korean lacquer tree (Rhus vernicifera Stokes), to 29 human cancer cell lines originated from 9 organs were evaluated. Their values of 50% growth inhibition were below 4 microg/ml, and showed cell line specific cytotoxicity. The present result is the first report on the cytotoxicity of urushiols suggesting that they would have an anticancer activity to human cancer cells. 相似文献