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61.
Gonococci that resist standard penicillin regimens by production of a penicillinase are now well established in certain areas of the world. Because cefoxitin, a semisynthetic cephamycin, resists gonococcal penicillinase in vitro, we compared procaine penicillin G and cefoxitin in treatment of gonorrhea in an area where 40 per cent of isolates produce penicillinase. One hundred and seven men with culture-proved gonococcal urethritis were given a single dose of either procaine penicillin G, 4.8 million U, or cefoxitin, 2 g, intramuscularly. Both groups took 1 g of probenecid orally; cefoxitin was given with lidocaine to reduce pain at the injection site. In men infected with penicillinase-negative gonococci, both cefoxitin and penicillin were highly effective. Penicillin failed in 77 per cent of men with penicillinase-positive strains, whereas cefoxitin was completely successful. Cefoxitin is an effective alternative to spectinomycin for single-session therapy of urethritis caused by penicillinase-producing Neisseria gonorrhoeae.  相似文献   
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BACKGROUND: Binding of allergens with IgE to the IgE receptors on mast cells and basophils results in the release of inflammatory mediators as sulfidoleukotrienes (SLTs), triggering allergic cascades that result in allergic symptoms, such as asthma and rhinitis. OBJECTIVE: We sought to investigate whether anti-IgE (Oma-lizumab), a humanized monoclonal anti-IgE antibody, in addition to specific immunotherapy (SIT) affects the leukotriene pathway. METHODS: Ninety-two children (age range, 6-17 years) with sensitization to birch and grass pollens and with seasonal allergic rhinitis were included in a phase III, placebo- controlled, multicenter clinical study. All subjects were randomized to one of 4 treatment groups. Two groups subcutaneously received birch SIT and 2 groups received grass SIT for at least 14 weeks before the start of the birch pollen season. After 12 weeks of SIT titration, placebo or anti-IgE was added for 24 weeks. The primary clinical efficacy variable was symptom load (ie, the sum of daily symptom severity score and rescue medication score during pollen season). Blood samples taken at baseline and at the end of study treatment after the grass pollen season were used for separation of leukocytes in this substudy. After in vitro stimulation of the blood cells with grass and birch pollen allergens, SLT release (LTC4, LTD4, and LTE4) was quantified by using the ELISA technique. RESULTS: Before the study treatment, SLT release to birch and grass pollen exposure did not differ significantly among the 4 groups. Under treatment with anti-IgE + SIT-grass (n = 23), a lower symptom load occurred during the pollen season compared to placebo + SIT-grass (n = 24, P =.012). The same applied to both groups receiving birch SIT (n = 23 and n = 22, respectively; P =.03). At the end of treatment, the combination of anti-IgE plus grass SIT, as well as anti-IgE plus birch SIT, resulted in significantly lower SLT release after stimulation with the corresponding allergen (416 ng/L [5th-95th percentile, 1-1168] and 207 ng/L [1-860 ng/L], respectively) compared with placebo plus SIT (2490 ng/L [384-6587 ng/L], P =.001; 2489 ng/L [1-5670 ng/L], P =.001). In addition, treatment with anti-IgE was also followed by significantly lower SLT releases to the allergens unrelated to SIT (grass SIT: 300 ng/L [1-2432 ng/L] in response to birch allergen; birch SIT: 1478 ng/L [1-4593 ng/L] in response to grass pollen) in comparison with placebo (grass SIT: 1850 ng/L [1-5499 ng/L], P =.001; birch SIT: 2792 ng/L [154-5839 ng/L], P =.04]. CONCLUSION: Anti-IgE therapy reduces leukotriene release of peripheral leukocytes stimulated with allergen in children with allergic rhinitis undergoing allergen immunotherapy independent of the type of SIT allergen used.  相似文献   
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Serum samples from 316 patients visiting the Dutch National Hemophilia Center were collected from 1979 to 1993 and stored at ?30°C. Patients were placed into three different groups: (1) patients ever treated with large pool non-hepatitis C virus (HCV)-safe concentrate (n=179); (2) patients treated with cryoprecipitate (n = 125); and (3) patients treated exclusively with HCV-save concentrate (n=12). In order to examine the prevalence of HCV infection in the different treatment groups serum samples were tested retrospectively for anti-HCV antibody using second generation enzyme-linked immunosorbent assay (ELISA) and recombinant immunoblot assay (RIBA-2). Significant differences in the prevalence of HCV infection were found between these 3 groups (group 1: 99%, group 2: 66%, group 3: 0%). The safety of currently administered clotting products is demonstrated in 57 patients who remained without HCV markers between 1989 and 1993. To examine the natural course of HCV infection fresh-frozen plasma samples were obtained recently from a subgroup of 277 hemophilia patients for HCV-RNA detection by a well-validated cDNA-PCR assay. In contrast to other reports, no evidence was found for seronegative HCV carriers. None of 52 patients without anti-HCV had detectable HCV-RNA. Of 225 patients with anti-HCV, 182 (81%) were HCV-RNA positive. None of 39 anti-HCV positive patients with a negative HCV-RNA reaction had serum alanine aminotransferase (ALT) levels above 50 U/l, whereas 44% of HCV-RNA positive patients had persistently elevated ALT levels above 50 U/l. These results indicate that 20% of hemophilia patients who have been infected with HCV in the past eliminated the virus or have viral replication below the detection limit of polymerase chain reaction (PCR) without biochemical evidence of liver damage. © 1995 Wiley-Liss, inc.  相似文献   
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Pål  Møller  Odd  Vinje Kåre  Berg 《Clinical genetics》1982,21(3):215-221
One hundred and twenty-two consecutively hospitalized patients with ankylosing spondylitis (AS) were reexamined. Ninety-two per cent were HLA B27 positive. Of the HLA B27 negative patients, 60% were found to have psoriasis, as opposed to 11 % of the HLA B27 positive patients. Acute anterior uveitis (AAU) was found only in HLA B27 positive patients, and more frequently in males than in females. The genetic and clinical heterogeneity of AS, together with the overlapping clinical criteria for AS and psoriatic spondylitis, may make the term "Bechterew's syndrome" preferable. Based on these findings and previous reports, we conclude that (i) AAU is a manifestation of Bechterew's syndrome in HLA B27 positive patients, (ii) HLA B27 negative patients without any obvious accompanying manifestations may suffer from psoriatic spondylitis, and (iii) genetic predisposition to psoriasis in persons who are HLA B13, B17 and B37 negative, may interact with the genetic predisposition to Bechterew's syndrome in HLA B27 positive persons and produce Bechterew's syndrome with psoriasis or psoriasis-like skin eruptions.  相似文献   
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Caspersson's method of labelling chromosomes with DNA-binding fluorescent agents has been applied to the study of human chromosomes. Fluorescence distribution curves of normal metaphase chromosomes treated with quinacrine mustard (QM) were obtained by scanning transparent pictures of the labelled chromosomes in a Beckman Analytrol® an instrument normally used for scanning electrophoresis strips. Representative fluorescence distribution curves of the different chromosomes, as well as one complete "QM karyotype", have been presented. The distribution curves of individual chromosomes appear to be characteristic and reproducible and it was concluded that the technique of fluorescent labelling holds great promise for identification of individual human chromosomes end chromosomal regions.  相似文献   
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