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Earlier studies have demonstrated that pentoxifylline (PTX) and platelet-activating factor (PAF) can significantly improve the motion parameters of post-thaw human spermatozoa. This study has investigated the effects of PAF, PTX and their combination on cyclic adenosine monophosphate (cAMP) concentrations and membrane lipid peroxidation (LPO) in post-thaw human spermatozoa. Washed spermatozoa from normal volunteers (n = 10) were cryopreserved in Test-yolk buffer using a standard protocol. After 2 weeks the sperm samples were thawed, washed and incubated with either 1 microM PAF, 3 mM PTX or 0.5 microM PAF plus 1.5 mM PTX. Video sequences were recorded at 0, 30, 60, and 120 min for analysis of sperm motion parameters using the Cell Track Sperm Analysis System. Concentrations of cAMP were assessed by radioimmunoassay, and LPO levels were measured by malondialdehyde-thiobarbituric acid reactivity. Our studies indicate a time-course stimulatory effect with overall maximal stimulation observed in samples treated with the combination of PAF and PTX. The maximal stimulation of percentage motility compared to control was observed at 60 min in samples treated with PAF, PTX, or PAF plus PTX. PAF plus PTX stimulated straight-line velocity (VSL), curvilinear velocity (VCL) and lateral head displacement (ALH) after 30 min incubation. The primary effect of PAF was observed on VSL, while the main effect of PTX was on VCL. cAMP concentrations were 3-fold higher than controls in samples treated with PTX or PAF plus PTX. cAMP concentrations in PAF-treated samples did not differ significantly from controls. No significant differences were observed between any groups for LPO.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
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Streptokinase-streptodornase (SK-SD) induced immediate and delayed skin test reactions in a high proportion of patients with disorders in which beta-streptococcal infection may be involved. The P-K test and absorption experiments with antigen or anti-IgE suggested that the immediate reaction was mediated by specific IgE antibody against SK-SD. Furthermore, the ratio of specific IgE antibody against SK-SD to total IgE was roughly calculated to be 20 percent. Finally, the RAST technique was applied to detect specific IgE antibody against SK-SD which showed high radiocounts bound to SK-SD-coupled particles in the sera of nephrotic patients who had a strong immediate reaction against SK-SD and a severe disease state. 相似文献
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JW Taylor AJ McLean RG Leonard TM Ludden U Clibon BP du Souich SC Harris D Lalka RL Talbert N Vicuna CA Walton JL McNay 《Canadian Metallurgical Quarterly》1979,19(1):1-7
International statistics indicate that there is a close correlation between the consumption of saturated fats (dairy fats and meat fats) and the mortality from coronary heart disease (CHD), and this conception has been confirmed by many epidemiological studies. Such studies alone, however, cannot prove the existence of a cause-and-effect relationship between these two variables; dietary intervention trials are needed. The Finnish Mental Hospital Study was such a trial, conducted in two hospitals near Helsinki in 1959--1971. Practically total replacement of dairy fats by vegetable oils in the diets of these hospitals was followed by a substantial reduction in the mortality of men from CHD. Total mortality also appeared to be reduced. As to the causes of death other than CHD, none was significantly influenced by dietary change. This was also true for malignant neoplasms. To alleviate the burden of CHD on public health, many investigators have recommended important changes in the quantity and quality of dietary fats. 相似文献
89.
The frequency and severity of CNSLD was studied in workers of an Hungarian firm (Ganz-Mavag) by means of questionnaire. Symptoms of CNSLD can be found more frequently in workers with air pollution than in those without. The symptoms of CNSLD show an age-dependence with regard to frequency and grade of severity, the single symptoms of CNSLD not occurring simultaneously and changing in their proportional frequency. 相似文献
90.
Fourteen women with amenorrhea-galactorrhea were treated with bromo-ergocryptine. Serum prolactin hPRL, hLH, hFSH, estradiol 17-beta (E2), and progesterone values were determined before and during treatment. No consistent pretreatment hormonal pattern was found. During treatment hPRL levels fell in 13 of 14 patients, and E2 rose in 12 of 14 patients. Levels of hLH became normal, and amounts of hFSH did not change. Galactorrhea lessened in all cases and ceased in 11. Menses resumed in 11 patients and 3 women became pregnant. Cessation of galactorrhea and resumption of menses occurred irrespective of initial hPRL or hLH levels. It is suggested that improvement of galactorrhea and resumption of menses in some patients with normal hPRL values are the result of increased serum E2 levels and may be due to a direct action of bromo-ergocryptine on the ovary. Bromo-ergocryptine may also be effective in treatment of amenorrhea, unassociated with galactorrhea or elevated hPRL levels. 相似文献