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A study of some antiparasitic properties of several homoallylamines and related tetrahydroquinolines and quinolines, previously described, was carried out using in vitro activity assays against the epimastigote form of Trypanosoma cruzi and against Trichomonas vaginalis. Unspecific cytotoxicity against murine macrophages was also studied. Although the antichagasic and trichomonacidal activities are not comparable to those of the standard drugs, nifurtimox and metronidazole, some of the compounds exhibit an interesting specific antiparasitic activity.  相似文献   
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OBJECTIVE: To determine the incidence of deep venous thrombosis (DVT) recurrence in young people, and its association with some genetic polymorphisms (FV G1691A, FII G20210A, MTHFR C677T, PAI-1 4G/5G). DESIGN: Prospective cohort study. METHODS: A database was established prospectively to follow-up a cohort of unselected patients who had had a first episode of objectively proven DVT under the age of 40 years. All patients had DNA analysis for heritable thrombophilia. We excluded patients with deficiency of antithrombin, protein C or protein S, malignant disease, antiphospholipid syndrome, or a requirement for long-term antithrombotic treatment. The end-point was objective evidence of symptomatic DVT recurrence. RESULTS: Eighty-seven patients were enrolled in the study. Mean duration of follow-up was 4.07 years. At 2 years, the cumulative recurrence rate was 19.3%. The risk of risk was not related to presence or absence of laboratory evidence of genetic polymorphisms: FV G1619A (HR 1.26 [95%CI: 0.64-2.46]; p = 0.51), FII G20210A (HR 0.81 [95%CI: 0.35-1.89]; p = 0.62), MTHFR C677T (HR 1.26 [95%CI: 0.56-2.81]; p = 0.58), PAI-1 4G/5G (0.84 [95%CI: 0.35-2.05]; p = 0.71). CONCLUSION: In this study, the risk of recurrent deep venous thrombosis in young people was not related with the presence of FV G1691A, FII G20210A, MTHFR C677T or PAI-1 4G/5G polymorphisms.  相似文献   
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We report the generation of murine triomas by fusing splenocytes from mice previously immunized with HBsAg ay-subtype and a hybridoma, secreting anti-HBsAg ad-subtype monoclonal antibody, which was rendered HGPRT- by induced mutagenesis with N-methyl-N'nitro-N-nitrosoguanidine. The fusion yielded a 83.8% of hybrids showing the antigen specificity of the parental hybridoma and a 16.1% of bi-specific monoclonal antibodies. One of them, coded as 1C8A5, showing a heavy chain isotype (IgG1/IgG2b) was used as capture reagent in an ultramicro-ELISA. As little as 0.78 I.U. of both HBsAg ad- and ay-subtypes could be realiably detected.  相似文献   
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Between 1965 and 1986 we saw 36 children with enuresis and urinary tract infection in association with “inversion” of facial expression when laughing. Urologic work-up of these patients disclosed characteristic findings of mild neuropathic bladder in all cases, with severe urinary tract damage in most of them. The clear association of distortion in facial expression and neuropathic bladder with resultant damage to the genitourinary tract should prompt urological evaluation of individuals with “inversion” of facial expression. About two thirds of the patients also had moderate to severe constipation. We suggest the term urofacial syndrome for this disorder. The occurrence of the disorder in multiple sibs, normal parents, increased parental consanguinity, and equal sex ratio indicate autosomal recessive inheritance.  相似文献   
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OBJECTIVE: We assessed the prevalence of HIV infection and associated risk behaviors among street-recruited young injection drug users (IDUs) in San Francisco. METHODS: In a cross-sectional study, 304 young (age <30 years) IDUs with a history of injecting in the previous 30 days were interviewed and tested for antibodies to HIV. Analyses assessing independent associations with HIV infection were limited to males only, due to the low number of infections in women. RESULTS: The prevalence of HIV infection was 5.3% overall but was highly stratified by gender and sexual preference (15.6% among homosexual/bisexual men vs. heterosexual men) and recruitment neighborhood (18% in the Polk Street area). Of 16 HIV infections, 14 (88%) were in males. Factors independently associated with HIV infection in males included sexual preference (homosexual/bisexual vs. heterosexual: adjusted odds ratio [AOR], 7.5; 95% confidence interval [CI], 1.5-36.6), recruitment neighborhood (Polk Street neighborhood vs. other neighborhoods: AOR, 4.8; 95% CI, 1.4-16.7), and duration of residence in San Francisco (>or=1 year vs. <1 year: AOR, 11.8; 95% CI, 1.4-95.8). CONCLUSIONS: The prevalence of HIV infection was highest among male IDUs who have sex with men. The strong associations between HIV infection and sexual orientation and HIV infection and recruitment locale suggest that risk may be attributable largely to sexual risk. In addition to successful prevention efforts aimed at reducing needle-associated risk, current intervention models aimed at young IDUs should target high-risk neighborhoods and emphasize sexual risk reduction measures, in particular among men who have sex with men.  相似文献   
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BACKGROUND: Despite the increasing use of currants in culinary recipes, currant allergy has rarely been reported. OBJECTIVES: To study a case of currant allergy and to explore cross-reactivity between grass pollen and Rosaceae family fruit allergens. METHODS: Skin prick tests to pollen and skin prick-to-prick tests with currants and peach were performed. Specific IgE levels were determined using the CAP method. We prepared a protein extract of 0.1 mg/mL in phosphate-buffered saline using red currant in the presence of protease inhibitors. Immunoblot inhibition studies were performed to explore cross-reactivity between grass pollen and currant allergens. RESULTS: Skin prick test results were positive to Dactylis, arizonic, and olive pollens. Results of skin prick-to-prick tests with fresh red and black currants were negative and positive, respectively, to peach. The specific IgE level was 5.7 KU/L to red currant and 2.92 KU/L to peach (CAP). Western blot analysis with red currant extract revealed specific IgE protein bands of 37 and 26 kDa. Preincubation of sera with extracts from red currant and peach inhibited both IgE bands, and preincubation with Dactylis pollen inhibited the 37-kDa band only. CONCLUSIONS: We report a case of allergy to grass pollen with an oral allergy syndrome involving several fruits from 2 different families of the Rosidae subclass confirmed by in vitro tests. Inhibition studies demonstrated cross-reactivity between different fruits (currant and raspberry) from the Rosidae subclass and were incomplete with grass pollen allergens.  相似文献   
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Summary A new technique is described for detecting nociceptor activity in microelectrode recordings from cutaneous fascicles of the human median nerve. The search strategy involves combined intraneural microstimulation and microneurographic recording in intrafascicular sites, where a critically low electrical stimulus amplitude evokes a threshold sensation of pain. From the subject's projection of pain to a small area of skin, the experimenter is guided to receptive fields of recordable nociceptor units. This technique has allowed, for the first time, to identify and study receptive properties of very high threshold nociceptors with A and C fibres in the glabrous skin of the human hand.  相似文献   
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