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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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Mean subcutaneous tissue PO2 (PsqO2) measurements were obtained in dogs with an unheated electrode placed in an implanted Silastic tonometer, while PaO2 was increased in increments from 40 to 600 torr during normal, increased, and reduced blood volume. These changes reflect that the mean PsqO2 is approximately 10 torr below the PO2 of venous blood draining that tissue. Since PaO2 was already known, the oxygen content of arterial and venous blood entering and leaving this tissue could be determined by reference to blood-oxygen dissociation curves. Therefore, relative changes in blood flow could be calculated using the Fick principle. After a 20% blood loss, the PsqO2 measured during breathing of room air fell to 20% of baseline, corresponding to an 80% fall in sc blood flow; it remained low until the shed blood was returned despite compensatory changes in cardiac output. Rapid infusion of electrolyte solutions in normovolemic animals produced a temporary increase in local blood flow. Subcutaneous oximetry seems capable of quantifying peripheral perfusion and may be clinically useful.  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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Veno-arterial extracorporeal membrane oxygenation (ECMO) is a common modality of circulatory assist device used in children. We assessed the outcome of children who had ECMO following repair of congenital cardiac defects (CCD) and identified the risk factors associated with hospital mortality.  相似文献   
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