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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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Acute myelocytic leukemia and prior allergies   总被引:1,自引:0,他引:1  
The relationship between prior allergies and adult acute myelocytic leukemia was investigated in a population-based case-control study. Based on data from personal interviews of 98 cases and 133 controls, a history of any type of allergy was associated with a significantly decreased risk of acute myelocytic leukemia (OR = 0.35, 95% CI = 0.20-0.60). Risk declined with the total number of specific allergies reported (p less than 0.001), and was reduced in relation to a history of prior asthma, eczema and hives. The implications of these findings in relation to natural immune surveillance against developing neoplasms are discussed.  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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OBJECTIVES. Primary care medical clinics are good settings for smoking interventions. This study extends this strategy with a smokeless tobacco intervention delivered by dentists and dental hygienists in the course of routine dental care. METHODS. Male users of moist snuff and chewing tobacco (n = 518) were identified by questionnaire in clinic waiting rooms and then randomly assigned to either usual care or intervention. The intervention included a routine oral examination with special attention to the part of the mouth in which tobacco was kept and an explanation of the health risks of using smokeless tobacco. After receiving unequivocal advice to stop using tobacco, each patient viewed a 9-minute videotape, received a self-help manual, and was briefly counseled by the dental hygienist. RESULTS. Long-term success was defined as no smokeless tobacco use at both 3- and 12-month follow-ups, with those lost to follow-up counted as smokeless tobacco users. The intervention increased the proportion of patients who quit by about one half (12.5% vs 18.4%, P < .05). CONCLUSIONS. These results demonstrate the efficacy of a brief dental office intervention for the general population of smokeless tobacco users.  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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Following its benchmark discovery, nitric oxide (NO) is nowknown to play important functional roles in a variety of physiologicalsystems. Within the vasculature, NO induces vasodilation, inhibitsplatelet aggregation, prevents neutrophil/platelet adhesionto endothelial cells, inhibits smooth muscle cell proliferationand migration, regulates programmed cell death (apoptosis) andmaintains endothelial cell barrier function. NO generated byneurons acts as a neurotransmitter, whereas NO generated bymacrophages in response to invading microbes acts as an antimicrobialagent. Because neurons, blood vessels and cells of the immunesystem are integral parts of the reproductive organs, and inview of the important functional role that NO plays in thosesystems, it is likely that NO is an important regulator of thebiology and physiology of the reproductive system. Indeed, inthe past 10 years, NO has established itself as a polyvalentmolecule which plays a decisive role in regulating multiplefunctions within the female as well as the male reproductivesystem. This review provides an overview of the role of NO invarious reproductive organs under physiological and pathologicalconditions.  相似文献   
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