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排序方式: 共有5918条查询结果,搜索用时 15 毫秒
41.
Jochen Fahrenberg Fritz Foerster Hermann-Josef Schneider Wolfgang Müller Michael Myrtek 《Psychophysiology》1986,23(3):323-333
The predictability of individual differences in activation processes was investigated in a multi-method laboratory-field study. Male students of physical education (N=58) were examined under various emotionally activating and physically demanding conditions (mental arithmetic, reaction time, free speech, cold pressor test, bicycle ergometer). The assessment included multi-channel recordings of pre-start phases in an athletic stadium and performance on a 1000 m run. Basal heart rate was also recorded during sleep. This multi-situational assessment was repeated after three weeks, three months, and, for most (N=42) subjects, after one year. Significant relationships exist between scores from corresponding conditions of relaxation, anticipation, and performance of physical exercise. However, with the exception of heart rate, correlation coefficients are rather small and seem to be of questionable predictive validity. A generalizability study further supports the general conclusion: To increase the practical relevance in psychophysiological investigations of stress/strain phenomena, such studies should directly assess individual differences in the criterion situations themselves. 相似文献
42.
Vicari E 《Human reproduction (Oxford, England)》2000,15(12):2536-2544
To evaluate whether bacteriological cure, sperm outcome, spontaneous pregnancy rate and white blood cell (WBC)-related reactive oxygen species (ROS) production were related to the extent of the infection and to an intermittent and repetitive antimicrobial treatment, 122 patients with bacterial [>10(5) colony-forming units (CFU)/ml] male accessory gland infections (MAGI) were studied. According to ultrasound criteria, patients had prostatitis (PR, n = 52), prostatovesiculitis (PV, n = 32) or prostatovesiculoepididymitis (PVE, n = 38). Each group was further subdivided into two subsets: one subset (PR, n = 40; PV, n = 20; PVE, n = 25) was given ofloxacin or doxycycline for 14 consecutive days per month for 3 months; the other subset (PR, n = 12; PV, n = 12; PVE, n = 13) received no treatment. The female partners were also treated. All patients were evaluated before, during (1 and 3 months) and after (3 months) treatment. The bacteriological cure rate was the highest (92.5%) after the third antibiotic course in PR, followed by PV (70.4%), and the lowest in PVE (52.0%). At 3 months after therapy discontinuation, some sperm parameters, seminal WBC concentration and ROS generation (assessed in the 45% Percoll fraction) were ameliorated in PR and PV, whereas no improvement occurred in patients with PVE, except for the percentage of coiled tails. Antibiotic treatment in PR and PV patients led to positive effects on sperm output and spontaneous pregnancy rate (40%) by removing pro-oxidant noxae (microbial and/or WBC-related ROS production). The persistent infertility, dyspermia and sperm-derived ROS overproduction in PVE may relate to a significant percentage of antibiotic-independent re-infection and/or to low antioxidative epididymal properties, which persisted following antimicrobial treatment. 相似文献
43.
Summary A randomized, placebo-controlled, double-blind crossover investigation in 12 patients with non-asthmatic chronic obstructive lung disease and co-existing stable angina pectoris was done to compare two 1-selective adrenoceptor blocking agents, atenolol 100 mg and bisoprolol 20 mg. Systolic and diastolic blood pressures (SBP, DBP), heart rate (HR) as well as airway resistance (AWR, and less frequently forced expiratory volume in 1 s (FEV1) and intrathoracic gas volume (ITGV) were measured in the sitting position before and at various times up to 24 h after drug intake.During the first 4 h both beta-blockers produced a significant reduction in HR in comparison to placebo (p<0.01). Atenolol 100 mg significantly increased AWR relative to placebo and bisoprolol (p<0.05). After 24 h, a significant reduction in HR (p<0.01) could only be demonstrated after bisoprolol, whereas atenolol alone led to a significant elevation in AWR relative to placebo and bisoprolol (p<0.05) at that time.It is concluded that bisoprolol appears to have a high degree of beta1-selectivity, thus providing a wide split between beta1- and beta2-adrenoceptor blockade. Bisoprolol in its therapeutic dose range is expected to be relatively safe as regards bronchoconstriction in patients suffering both from hypertension and/or angina pectoris and chronic obstructive lung disease. 相似文献
44.
Summary The plasma protein binding of amitriptyline, imipramine, clomipramine, and their primary demethylated metabolites were studied by means of a method combining dialysis and gas chromatography. Equilibrium in dialysis of serum containing amitriptyline and its metabolite nortriptyline was attained in about 0.5 h with the drug dissolved in the serum compartment, and in about 2 h with the drug passing from the buffer to the serum compartment.The calculation of free fractions was influenced by variations with dialysis time in the volumes of serum and buffer. Increase of pH in serum increased the protein binding of the weakly basic drugs studied, and made the Donnan distribution effects more pronounced. At pH 7.4, the Donnan effect was negligible.Binding parameters for the 6 tricyclic antidepressant substances studied were estimated for the binding to 1-acid glycoprotein and for total binding in serum. For 1-acid glycoprotein, the k-values ranged from 1·105 to 8·105 M–1, and for pooled serum from 0.4·105 to 8·105 M–1. The determined number of binding sites on the 1-acid glycoprotein was, on average 0.87 for the 6 substances. In serum, the binding capacity was 2–14 times the concentration of 1-acid glycoprotein. 相似文献
45.
目的探讨前列地尔辅助硫辛酸治疗糖尿病足溃疡合并感染对患者胰岛素样生长因子-1(IGF-1)、纤维连接蛋白(FN)、血管内皮生长因子(VEGF)水平及足背血流动力学的影响。方法选取2017年5月-2019年5月新疆医科大学第一附属医院收治的104例糖尿病足溃疡合并感染患者,采用随机数字表法将所选患者分为研究组(n=52)和对照组(n=52)。对照组给予硫辛酸进行治疗,研究组在此基础上给予前列地尔进行治疗,两组均治疗4周。比较两组治疗4周后的下肢静息疼痛改善情况,治疗前、治疗4周后的血清IGF-1、FN、VEGF水平及足背动脉血流速度和足背动脉内径,统计两组治疗期间的不良反应发生率。结果治疗4周后,研究组下肢静息疼痛总改善率为96.15%,高于对照组(P<0.05)。与治疗前比,治疗4周后,两组血清IGF-1、FN、VEGF水平及足背动脉血流速度、足背动脉内径均升高,且研究组均高于对照组(P<0.05)。治疗期间,研究组不良反应发生率为5.77%,低于对照组(P<0.05)。结论前列地尔辅助硫辛酸治疗糖尿病足溃疡合并感染,可显著提高患者血清IGF-1、FN、VEGF水平,改善其足背血流动力学,并能缓解患者下肢静息疼痛,降低不良反应发生率。 相似文献
46.
尼卡地平和硝酸甘油在体外循环中血压控制的比较 总被引:1,自引:0,他引:1
目的比较尼卡地平和硝酸甘油在体外循环中控制高血压的效果及对血流动力学的影响。方法40例冠状动脉旁路术(CABG)病人在体外循环(CPB)中平均动脉压升至10.7kPa时给予尼卡地平或硝酸甘油。将病人随机分为尼卡地平和硝酸甘油组,每组20例。观察两药起效时间,维持平均动脉压(MAP)在665~9.31kPa时所需剂量,开放升主动脉后心脏自动复跳情况以及停机后血流动力学的变化。结果将MAP从10.7kPa降至6.65~9.31kPa时,应用尼卡地平0.5mg,所需时间为(3.8±1.3)min,维持MAP在6.65~9.31kPa时所需剂量为(1.2±0.4)μg·kg 相似文献
47.
Shayan Taheri Farshid Davoodi Abbas Raisi Amir Zakian Asghar Rajabzadeh Mohammad Hassan Hablolvarid Abdolrahman khezri Hassan Ahmadvand 《Andrologia》2021,53(6):e14049
Testicular torsion/detorsion is one of the important emergencies that requires fast surgical intervention. This study aimed to investigate the effects of Salvia miltiorrhiza hydroalcoholic extract combined with verapamil on testicular ischaemia/reperfusion damage in Wistar albino rats. All animals were distributed in 3 groups (n = 8), including the sham-operated group, torsion/detorsion (TD) group and torsion/detorsion + pretreatment with 200 mg/kg Salvia miltiorrhiza extract combined with 0.3 mg/kg verapamil (SMV) group. Oxidative stress biomarkers (MDA, GPx, CAT and TAC) both in plasma and testicular tissue, sperm parameters (motility, vitality, concentration and morphology) and histopathological parameters (MSTD, GECT, Johnson's score, Cosentino's score and testicular cell thickness) were assessed in all groups. Ischaemia/reperfusion significantly increased MDA and decreased GPx, CAT and TAC levels (p < .05). Pretreatment with SMV significantly increased GPx, CAT and TAC levels (p < .05). SMV group increased progressive sperm motility and vitality and reduced non-progressive motility of spermatozoon (p < .05). Testicular torsion significantly decreased all histopathological parameters compared to the sham group (p < .05). SMV pretreatment remarkably increased MSTD, GECT and Cosentino's score in comparison with the TD group (p < .05). A combination of Salvia miltiorrhiza with verapamil could reduce damages triggered by testicular torsion detorsion and improve sperm functionality parameters and oxidative stress defence systems. 相似文献
48.
Clomiphene, a selective oestrogen receptor modulator, has been utilised in managing male sub-fertility since 1967. Numerous controlled and uncontrolled studies have been published regarding the efficacy of clomiphene citrate in male sub-fertility cohorts. Although the primary intention of treating men with clomiphene citrate is to improve sperm parameters and testosterone levels, some studies have reported paradoxical decline in semen parameters. The information available on decline in sperm parameters following treatment with clomiphene is sparse. We conducted a systemic review using PubMed, Embase, Cochrane Library and Scopus databases for original studies reporting adverse effects of clomiphene citrate therapy on sperm parameters. This systematic review includes 384 men from 11 different studies that reported adverse effects of clomiphene citrate therapy. Of the men included in these studies, 19%, 21%, 17% and 24% of clomiphene-treated men demonstrated a decrease in sperm count, concentration, motility and total motile sperm count respectively. In up to 17% of patients, deterioration of semen parameters did not recover following discontinuation of therapy. In the future, more studies should report on this aspect so the magnitude of this effect can be more clearly understood. 相似文献
49.
Luca Boeri Federico Belladelli Paolo Capogrosso Walter Cazzaniga Luigi Candela Edoardo Pozzi Luca Valsecchi Enrico Papaleo Paola Viganò Costantino Abbate Filippo Pederzoli Massimo Alfano Francesco Montorsi Andrea Salonia 《Andrologia》2021,53(1):e13861
A proportion of men are infertile despite having normal medical history/physical examination and normal semen analysis. We aimed to assess whether normal sperm parameters per se account for male factor fertility. 1,957 infertile men were compared with 103 age-comparable fertile controls. Semen analysis was based on 2010 World Health Organization reference criteria. Of all, 12.1% of infertile men and 40.8% of fertile men presented with normal sperm parameters. Among fertile men, 36.9% had isolated sperm abnormalities and 22.3% men showed two or more concomitant sperm abnormalities. Serum total testosterone was higher in infertile men with normal sperm parameters compared to those with ≥2 sperm abnormalities or azoospermia, but similar to those with isolated sperm abnormalities (p ≤ .001). Circulating hormones were similar among sperm parameters groups in fertile men. At multivariable analyses, testicular volume (OR 1.12, p ≤ .001) and FSH (OR 0.8, p ≤ .001) were associated with normal sperm parameters. Overall, the longer the infertility period, the greater the number of sperm parameters abnormalities (p < .01). In conclusion, we found that 12% of infertile men and only 41% of fertile men present with normal sperm parameters. Normal sperm parameters per se do not reliably account for fertility in the real-life setting. 相似文献
50.
Carlo Giulioni Valentina Maurizi Simone Scarcella Manuel Di Biase Valerio Iacovelli Andrea Benedetto Galosi Daniele Castellani 《Andrologia》2021,53(11):e14215
Our purpose was to review and analyse the impact of pyrethroids and organophosphates exposure on human semen parameters. A comprehensive literature search was performed through MEDLINE via PubMed, Scopus and Webscience. Only cohort studies examining semen parameters in workers or general populations exposed to pyrethroids or organophosphates were included. Ejaculate volume, sperm count, concentration, motility, viability, normal morphology and seminal pH alterations were pooled using the Cochran–Mantel–Haenszel Method with the random effect model and expressed as weighted mean difference, risk ratios, 95% confidence intervals and p-values. Seven cross-sectional studies regarding pyrethroids were included. Four of them were eligible for meta-analysis. The only parameter affected by pyrethroid exposure was normal sperm morphology (WMD-7,61%, 95%CI –11,92 to −3,30;p = 0,0,005). Nine studies were selected to evaluate the impact of organophosphates on semen parameters with six of them eligible for meta-analysis. A significant reduction was detected for the following: ejaculate volume (WMD −0,47ml, 95%CI −0,69 to −0,25; p < 0,0001), sperm count (WMD-40,03, 95%CI −66,81 to −13,25;p = 0,003), concentration (WMD-13,69 x10⁶/mL, 95%CI −23, 27 to-4,12;p = 0,005) and motility (WMD −5,70%, 95%CI −12,89 to 1,50;p = 0,12). Despite the increase in sperm abnormality, it has been shown that pyrethroids are unrelated to reduced sperm quality. However, the negative association of organophosphates with spermatogenesis is noteworthy. 相似文献