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OBJECTIVE: Varicocele is the most common treatable cause of male infertility and is associated with progressive decline in testicular function. Varicocelectomy, a commonly performed operation, is indicated in infertile males with varicoceles who have oligospermia, asthenospermia, teratospermia or a combination of these factors. It is not clear if varicocelectomy is indicated if the patients have normal sperm density associated with asthenospermia or teratospermia. METHODS: We reviewed 167 patients with varicocele-associated male infertility over a 7-year period (December 1999-November 2005). Pre- and post-varicocelectomy seminal fluid analyses, assessed using the World Health Organization criteria, were obtained at intervals of 4-6 months. Wilcoxon signed rank tests were used to evaluate for statistical significance and P < or = 0.05 was considered significant. RESULTS: The mean age of the patients and their spouses were 35 and 28 years, respectively. The mean duration of infertility was 3.2 years (range, 1.5-7.5). Oligospermia, teratospermia, asthenospermia, oligospermia, asthenospermia and teratospermia (OAT) syndrome and azoospermia were found preoperatively in 106 (63.5%), 58 (34.7%), 154 (92%), 118 (71%) and 15 (9%) patients, respectively. Overall, significant improvements in semen volume (P < 0.001), sperm density (P < 0.001), sperm motility (P < 0.001) and sperm vitality (P < 0.001) were obtained after varicocelectomy. There was, however, no significant improvement in sperm morphology after varicocelectomy (P = 0.220). When patients with preoperative oligospermia (sperm density, <20 million/mL) were considered separately, varicocelectomy led to significant improvement in all the semen parameters except the sperm morphology (P = 0.183). Conversely, when varicocele patients with a sperm density of > or =20 million/mL (normospermia) associated with asthenospermia and/or teratospermia were considered separately, they did not show significant improvement in any of the semen parameters after varicocelectomy (P > 0.05). In addition, azoospermic patients did not show significant improvement in any of the semen parameters (P > 0.05) CONCLUSION: No significant improvement in semen parameters may be obtained in patients with clinical varicocele and preoperative normospermia. It is possible that only patients with preoperative oligospermia may benefit from varicocelectomy. Larger multi-institutional studies are needed to determine more definitively if asthenospermia or teratospermia in normospermic subfertile males with clinical varicoceles are in fact indications for varicocelectomy.  相似文献   
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A total of 28 staphylococcal isolates from human clinical specimens belonging to the Staphylococcus sciuri group were identified and characterized. The API Staph and ID32 STAPH correctly identified S. sciuri and S. lentus but not S. vitulinus strains. Identification to the subspecies level was possible only by a PCR-based method.  相似文献   
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Tropical pyomyositis (TP) is a life‐threatening bacterial infection of the skeletal muscle that occurs particularly among children, young adults and those with immunocompromised conditions. The appropriate diagnosis and treatment are often delayed due to its non‐specific signs, leading to fatal consequences. Staphylococcus aureus, especially methicillin‐susceptible S. aureus, is responsible for most TP cases. However, other bacteria (i.e. streptococci, Pseudomonas aeruginosa, Escherichia coli, Klebsiella spp., Candida spp., Mycobacterium spp.) have been reported. This narrative review provides an update on the epidemiology and clinical course of TP. A special focus is laid on the role of toxins (i.e. Panton‐Valentine Leucocidin and α‐toxin) in the pathogenesis of TP and their implication for the clinical management of infection.  相似文献   
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Development of homogenous metal matrix nanocomposites with uniform distribution of nanoreinforcement, preserved matrix nanostructure features, and improved properties, was possible by means of innovative processing techniques. In this work, Al-SiC nanocomposites were synthesized by mechanical milling and consolidated through spark plasma sintering. Field Emission Scanning Electron Microscope (FE-SEM) with Energy Dispersive X-ray Spectroscopy (EDS) facility was used for the characterization of the extent of SiC particles’ distribution in the mechanically milled powders and spark plasma sintered samples. The change of the matrix crystallite size and lattice strain during milling and sintering was followed through X-ray diffraction (XRD). The density and hardness of the developed materials were evaluated as function of SiC content at fixed sintering conditions using a densimeter and a digital microhardness tester, respectively. It was found that milling for 24 h led to uniform distribution of SiC nanoreinforcement, reduced particle size and crystallite size of the aluminum matrix, and increased lattice strain. The presence and amount of SiC reinforcement enhanced the milling effect. The uniform distribution of SiC achieved by mechanical milling was maintained in sintered samples. Sintering led to the increase in the crystallite size of the aluminum matrix; however, it remained less than 100 nm in the composite containing 10 wt.% SiC. Density and hardness of sintered nanocomposites were reported and compared with those published in the literature.  相似文献   
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Background and aims: Trachoma is a sight-threatening process triggered by the infection of the conjunctiva with Chlamydiae. Blindness associated with trachoma was reported in Sahelian areas of Cameroon. However, data on the prevalence of this neglected infection in the Far North Region are not available. The aim of this study was a) to assess clinical trachoma and b) to detect Chlamydia in the conjunctiva of trachomatous populations living in the Far North Regions of Cameroon.Methods: A total of 2,423 randomly selected children (1–10 years) and 1,590 women over 14 from randomly selected villages from the Kolofata Health District (115,000 inhabitants) were included in a cross-sectional study in February 2009. Trained staff examined and obtained conjunctival swabs from trachomatous subjects. DNA was extracted and amplified to detect Chlamydia DNA by real-time PCR. The quality of sampling was assessed by quantifying the number of epithelial cells.Results: Children (2,397 or 98.9% of the predicted number) and women (1,543; 97.0%) were examined. The prevalence of follicular trachoma (TF) in children was 21% (95% CI 17.8–24.5) and of intense inflammatory trachoma (TI) 5.2% (95% CI 3.6–7.3). Among the women, trichiasis (TT) was observed in 3.4% (95% CI 2.4–4.7), corneal opacities (CO) in 1.4% (95% CI 0.8–2.3) and trachoma-related blindness in 0.9% (95% CI 0.4–1.8). Conditions related to income, illiteracy, latrines, water supply and animals wandering close to dwellings were similar in all the villages. PCR was positive in 35% of children with active trachoma and in 6% of adult females presenting TT and/or related corneal opacities.Conclusion: The prevalence of trachoma and the severe trachoma sequelae found during this survey underline the urgent need to implement efficient blindness prevention interventions to improve the visual future of the people in the Sahelian region.  相似文献   
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OBJECTIVE: To evaluate the sociodemographic and clinicopathological characteristics of patients with cervical cancer seen in a tertiary referral center in northern Nigeria. MATERIALS AND METHODS: Between January 2002 and December 2004, 70 consecutive patients with histologically confirmed cervical cancer, with a median age of 48 years (range, 30-75 years), were interviewed on the basis of a structured pro forma. RESULTS: Of these patents, 39 (56%) had had no formal education, and 36 (51%) were unemployed housewives. Sixty (86%) had become sexually active before 17 years of age; 44 (63%) were in polygamous families, and 25 (36%) patients were in at least a second marriage. There was an average of 6.8 live births per patient. Vaginal bleeding was seen in all patients, and 55 (79%) had vaginal discharges; 50 (71%) had a bulky cervical mass, and 46 (66%) presented with at least Stage IIIA disease. Squamous cell carcinoma was the commonest histology. The three HIV-seropositive patients were young and had advanced disease. CONCLUSION: Sociodemographic factors, such as low socioeconomic level, early age at first sexual intercourse and multiple sexual partners, place women at high risk of developing cervical cancer in northern Nigeria. Late presentation with advanced disease predominates.  相似文献   
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BACKGROUND: Concentric intimal thickening and the infiltration of inflammatory cells in cardiac allografts are the pathological hallmark characteristics of chronic vascular rejection (CVR), the leading cause of long-term graft failure. The precise mechanisms involved in the development and pathogenesis of CVR remain elusive. In the PVG-R23 to PVG-RT1u rat model of CVR, prior administration of a donor-specific transfusion (DST) was previously shown to prolong graft survival indefinitely and abolish the vascular lesions associated with CVR. The present study investigates in more depth the underlying mechanisms involved in the subsequent prolongation of allograft survival and inhibition of CVR by DST. METHODS: R23 heart grafts were monitored in nontransfused and transfused RT1u recipients injected 2 weeks before transplantation with 1.5 ml of R23 blood. Severity of arteriosclerosis, transplant infiltrate, transforming growth factor (TGF)-beta1 protein expression within the graft, plasma TGF-beta1 levels, class II MHC expression, tenascin protein expression, and serum alloantibody levels were measured. RESULTS: There was no significant difference in donor MHC class II, myocardial TGF-beta1, or tenascin expression between DST and non-DST-treated recipients. However, DST-pretreated recipients showed greatly reduced histological evidence of CVR and had lower titers of R23-specific IgG subclasses. Furthermore, DST-treated allograft recipients showed significant decreases in circulating TGF-beta1 levels and a reduction in TGF-beta1 and tenascin expression within coronary arteries of the allografts. CONCLUSION: The results suggested that DST inhibited CVR by altering and regulating the expression of TGF-beta1, thereby preventing the fibrogenic effects associated with TGF-beta1.  相似文献   
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