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排序方式: 共有5245条查询结果,搜索用时 15 毫秒
41.
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
42.
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
43.
血氧饱和度和呼吸信号是人体重要的生理信号,呼吸的监测在临床以及生活中具有重要的意义。该研究建立了一套从光电容积脉搏波中提取呼吸信号的系统。包括脉搏波信号的采集、呼吸信号的提取以及从下位机中实时传输至上位机的呼吸率和脉率的计算。 相似文献
44.
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
45.
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
46.
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
47.
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
48.
目的 探究水-醇双提工艺下中药复方粉末影响颗粒流动性的关键物性参数。方法 以水-醇双提工艺下杏贝止咳颗粒(Xingbei Zhike Keli,XZK)、桂枝茯苓胶囊(Guizhi Fuling Jiaonang,GFJ)以及参乌益肾片(Shenwu Yishen Pian,SYP)3个中药复方品种的制粒前粉末与制粒后颗粒为研究对象,采用多元统计分析方法,绘制粉末物理指纹图谱,结合Pearson相关系数评价粉末质量一致性;采用主成分分析(principal component analysis,PCA)结合因子分析评价颗粒流动性;并构建以松装密度(Da)、振实密度(Dc)、休止角(α)、豪斯纳比(IH)、粒径<50μm百分比(Pf)、均匀性(HG)、均齐度(UN)、粒径(D10、D50、D60、D90)、分布宽度(span)、分布范围(width)、比表面积(SSA)、孔隙率(Ie)、卡尔指数(IC)、含水量(HR)、吸湿率(H... 相似文献
49.
目的:探讨脊柱-骨盆矢状位参数及关节突关节角度对退变性腰椎滑脱的影响及相关性研究。方法:以2016年7月至2019年9月确诊的120例L4-L5单节段退变性滑脱患者为观察对象(滑脱组),以性别和年龄相匹配的120例L4-L5节段退变性椎管狭窄患者为对照(对照组)。通过影像学资料测量如下参数:骨盆入射角(pelvic incidence,PI),骨盆倾斜角(pelvic tilt,PT),骶骨倾斜角(sacral slope,SS),腰椎前凸(lumbar lordosis,LL),胸椎后凸(thoracic kyphosis,TK),矢状面平衡(sagittal vertical axis,SVA),L4-L5头侧关节突关节角,尾侧关节突关节角及小关节不对称性。比较两组患者参数的差异并对有意义参数行Logistic回归分析。对退变性腰椎滑脱患者关节突关节方向与脊柱-骨盆参数进行相关性分析。结果:两组患者在PI、PT、LL、SVA、头侧关节突关节角、尾侧关节突关节角差异有统计学意义(P<0.05);Logistic回归分析发现PI、PT及头侧关节突关节角是腰椎滑脱程度的危险因素(P<0.05)。滑脱组头侧关节突关节矢状化与PI、PT呈现显著相关(P<0.05)。结论:高PI、PT及头侧关节突关节矢状化是腰椎滑脱的危险因素,并且关节突关节矢状化程度和大PI、PT密切相关。 相似文献
50.