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排序方式: 共有524条查询结果,搜索用时 19 毫秒
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R Zachariah AD Harries MP Spielmann V Arendt D Nchingula R Mwenda O Courtielle P Kirpach B Mwale FML Salaniponi 《Malawi medical journal : the journal of Medical Association of Malawi》2002,14(2):10-12
In Thyolo district, Malawi, an operational research study is being conducted on the efficacy and feasibility of co-trimoxazole prophylaxis in preventing deaths in HIV-positive patients with tuberculosis (TB). A series of cross-sectional studies were carried out to determine i) whether faecal Escherichia coli (E.coli) resistance to co-trimoxazole in TB patients changed with time and ii) whether the resistance pattern was different in HIV positive TB patients who were taking co-trimoxazole prophylaxis. Co-trimoxazole resistance among E.coli isolates in TB patients at the time of registration was 60% in 1999 and 77% in 2001 (p<0.01). Resistance was 89% among HIV-infected TB patients (receiving co-trimoxazole), while in HIV negative patients (receiving anti-TB therapy alone) it was 62% (p<0.001). The study shows a significant increase of E.coli resistance to co-trimoxazole in TB patients which is particularly prominent in HIV infected patients on co-trimoxazole prophylaxis. Since a high degree of plasmid-mediated transfer of resistance exists between E.coli and the Salmonella species, these findings could herald limitations on the short and long term benefits to be anticipated from the use of co-trimoxazole prophylaxis in preventing non-typhoidal salmonella bacteraemia and enteritis in HIV infected TB patients in Malawi. 相似文献
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Safety of outpatient peripheral angioplasty 总被引:2,自引:0,他引:2
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Summary— Beta-adrenergic receptors (β/-AR) belong to the large multigenic family of receptors coupled to GTP-binding proteins. Three subtypes have been identified: β1 -, β2 - and β3 -AR. Much of the work delineating the precise pharmacological comparison of the three β-ARs has come from investigations with stably transfected Chinese hamster ovary cells (CHO cells). This review discusses the structure and function of β3 -AR in various species and presents new findings on a number of β3 -AR ligands including carazolol, tertatolol and CL 316,243 which were found to be selective and potent β3 -AR agonists and ZD 2079 and salmeterol which appear to display full but non-subtype selective agonistic activity. Species-related variations of the β3 -AR pharmacology have been shown for propranolol and bupranolol. With the ongoing characterization of the β3 -AR at the molecular and cellular level, and with the advent of computer-assisted molecular modelling to aid in the determination of the three-dimensional structure of the receptor, it is thought that novel β3 -AR compounds will become available with improved selectivity and potency. 相似文献
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IM Balfour-Lynn B Valman M Silverman AD Webster 《Archives of disease in childhood》1993,68(4):472-476
It is unknown why some infants wheeze during upper respiratory tract infections. One possibility is that secretory IgA, which has a major role in mucosal defence against viral infection, might be deficient in wheezy infants. The nasal IgA response to upper respiratory tract infection in 32 wheezy infants (median age 5.8 months) was compared with nine siblings (median age 2.6 years) who had nasal symptoms only. Nasal lavage was performed during infections and on follow up when free from symptoms, using inulin as a marker of dilution to determine absolute concentrations of IgA in the nasal secretions. The two groups showed a similar increase in total IgA and total protein levels during infection, but secretory IgA concentrations were unchanged. This study shows that wheezy infants have a normal nasal IgA response to infection and that the increase in total IgA during early infection is due to plasma exudation rather than increased production of secretory IgA. 相似文献
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