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In order to evaluate the effects of pentoxifylline on sperm motility and longevity, a controlled in-vitro study was conducted on normozoospermic donor semen samples using the Cellsoft automated system for sperm motility analysis. After incubation and selection, pentoxifylline was found to improve the recovery of spermatozoa and to increase their velocity. In the subgroup of progressively motile spermatozoa, curvilinear velocity was also enhanced. It is concluded that pentoxifylline has an effect on the vigour, but not on the pattern, of sperm motion. Pentoxifylline did not improve the motility characteristics of senescent spermatozoa in normozoospermic sperm samples. Sperm survival, as shown by supra-vital staining, and motility longevity both decreased with time after pentoxifylline treatment.  相似文献   
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BACKGROUND: Blastomyces dermatitidis, the etiologic agent of blastomycosis, causes severe disease and substantial mortality in those immunocompromised by acquired immunodeficiency syndrome or malignancy. In solid organ transplant recipients, the epidemiology, clinical features, and outcomes have not been fully described. METHODS: We conducted a retrospective case-series at the University of Wisconsin Hospital and Clinics. Case patients were solid organ transplant recipients with blastomycosis. RESULTS: From 1986 to 2004, we identified 11 cases of post-transplant blastomycosis with 64% occurring between 2000 and 2004. Onset of infection occurred a median of 26 months post transplantation with near equal distribution before and after the first year of transplantation. Rejection did not precede any case of post-transplant blastomycosis. Opportunistic co-infections were common, occurring in 36% of patients. Pneumonia was the most common clinical presentation and was frequently complicated by acute respiratory distress syndrome (ARDS). Extrapulmonary disease predominantly involved the skin and spared the central nervous system. The overall mortality rate was 36%; however, this increased to 67% in those with ARDS. None of the surviving patients relapsed or received routine secondary antifungal prophylaxis. CONCLUSION: Blastomycosis is an uncommon infection following solid organ transplantation that is frequently complicated by ARDS, dissemination, and opportunistic co-infection. After cure, post-transplant blastomycosis may not require lifelong antifungal suppression.  相似文献   
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A study of 17 patients with autoimmune axonal or demyelinating peripheral neuropathy in combination with M-component is described. The M-component was associated with MGUS (monoclonal gammopathy of undetermined significance) in 12 patients, CLL in one patient, WaldenstrÖm's disease in one patient, and myeloma in three patients. Immunohistological examination with direct and indirect fluorescence showed binding of antibodies to nerve structures of the same class and light chain as seen in the M-component. In five cases of IgM M-component, the demyelinating neuropathy was caused by binding of the IgM M-protein and complement C3b to myelin-associated glycoproteins (MAG). In 12 cases with axonal neuropathy, binding of IgG to the connective tissue of the peri- and endoneurium was found in 50% of cases, IgM in five cases, and IgD in one case. None of the patients had central nervous system (CNS) symptoms. The clinical and therapeutic difficulties are discussed; only two patients with an acute course responded to immunosuppression. A marked co-expression of other autoimmune phenomena is interpreted in the light of cross-reactions between the autoantibody and similar tissue autoantigens.  相似文献   
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Listeriosis is a serious complication in patients undergoing treatment for cancer. We present antimicrobial susceptibility profiles of 84 clinical Listeria monocytogenes isolates. During 1955 to 1997, in vitro susceptibility for penicillin (97.6%), ampicillin (90.7%), erythromycin (98.8%), tetracycline (96.9%), and gentamicin (98.0%) remained unchanged. All isolates were susceptible to amikacin, ciprofloxacin, imipenem, rifampin, trimethoprim-sulfamethoxazole (TMP-SMX), and vancomycin. High prevalence of clindamycin resistance (96.2%) was unexpected. Ampicillin plus gentamicin is standard therapy for systemic listerosis, and TMP-SMX may be used for patients with beta-lactam intolerance. In vitro susceptibility profiles for carbapenem and fluoronated quinolone are promising, although clinical validation is critically needed before routine use is advocated, especially for listeric patients with severe cellular immune defects.  相似文献   
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Recently, in-vitro maturation (IVM) of immature human oocytes recovered from non-stimulated follicles has been applied in the treatment of infertility. However, in previous reports, very few embryos cultured in conventional medium have reached the expanded blastocyst stage following in-vitro maturation and fertilization (IVM/IVF). The objective of this study was to investigate whether the developmental competence of human embryos following IVM/IVF could be enhanced by the use of a human ampullary cell co-culture system. Immature human oocytes were aspirated from small follicles at Caesarean section and then cultured in medium containing human menopausal gonadotrophin for 36 to 48 h, followed by insemination. Zygotes were randomly cultured either in conventional culture medium alone or in the co-culture system. Of 48 embryos cultured in conventional medium alone, all arrested at the 2-16- cell stage on day 3 after insemination. Of 46 embryos cultured in the co-culture system, 26 embryos (56.5%) arrested at the 2-16-cell stage. Six embryos (13%) developed to the morula stage. Fourteen embryos (30.4%) developed to expanded blastocysts and two blastocysts were hatching on day 7 after insemination. We conclude that co-culture significantly enhances the development of blastocysts in embryos resulting from IVM/IVF.   相似文献   
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