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排序方式: 共有2074条查询结果,搜索用时 359 毫秒
91.
R. Adomaitis B. Vincel A. Eidukaite E. Ostaneviciute R. Kirka V. Bilius D. Malcius G. Verkauskas F. Hadziselimovic 《Andrologia》2016,48(9):1021-1026
Bilateral cryptorchidism treatment results are often shadowed by the majority of unilateral cases. We report the long‐term follow‐up results of boys treated for bilateral cryptorchidism during childhood. Patients treated in two main paediatric surgery centres were selected from medical registries and invited for a clinical examination including scrotal ultrasound, salivary testosterone measurement and a semen sample. Thirty‐six men (38.3%) replied to the written invitation, and 21 agreed to be examined. The mean age at orchidopexy was 74 months (range 24–138). Sperm count was 0.42 × 106 (SD ± 0.64 × 106) ml?1. The correlation between total testicular volume and total sperm count was statistically significant (r = 0.481; P = 0.032). These results show that surgical treatment of bilateral cryptorchidism after the age of 2 years does not prevent infertility. Sperm count and endocrine evaluation advocated after the treatment of bilateral cryptorchidism in all adult patients. 相似文献
92.
Ferdinando Antonio Gulino Emanuela Leonardi Ilaria Marilli Giulia Musmeci Salvatore Giovanni Vitale Vito Leanza 《Gynecological endocrinology》2016,32(1):65-68
Introduction: Myo-inositol (MI) is a precursor for the synthesis of phosphatidylinositol polyphosphates (PIPs). The aim of the study is to evaluate the effect of its administration on semen parameters of male patients undergoing an in vitro fertilization cycles.Methods: In vivo study. Samples were semen of 62 patients divided into three different groups: healthy fertile patients (Group A); patients with oligoasthenospermia (OA) (Group B); control group (CTR). The collected samples were analyzed by optic microscopy in order to evaluate semen’s volume, spermatozoa’s number and motility before and after density-gradient separation method. These parameters were evaluated before and after administration of 4000?mg/die of MI and 400?µg of folic acid for 2 months. The results were analyzed statistically with Student's t-test.Results: After treatment there was a significant increase of basal and after density-gradient separation method spermatozoa concentration in Group B, and a significant increase of spermatozoa count after density-gradient separation method in Group A. The motility values were higher in healthy men than patients with OA before treatment, but there was no improvement in both groups after treatment.Conclusions: Exogenous administration of MI significantly improves semen’s parameters both in patients with OA and in normal fertile men. 相似文献
93.
94.
Swan SH Liu F Overstreet JW Brazil C Skakkebaek NE 《Human reproduction (Oxford, England)》2007,22(6):1497-1502
BACKGROUND To look at possible long-term risks from anabolic steroids and other xenobiotics in beef, we examined men's semen quality in relation to their mother's self-reported beef consumption during pregnancy. METHODS: The study was carried out in five US cities between 1999 and 2005. We used regression analyses to examine semen parameters in 387 partners of pregnant women in relation to the amount of beef their mothers reported eating while pregnant. Mothers' beef consumption was also analysed in relation to the son's history of previous subfertility. RESULTS Sperm concentration was inversely related to mothers' beef meals per week (P = 0.041). In sons of "high beef consumers" (>7 beef meals/week), sperm concentration was 24.3% lower (P = 0.014) and the proportion of men with sperm concentration below 20 x 10(6)/ml was three times higher (17.7 versus 5.7%, P = 0.002) than in men whose mothers ate less beef. A history of previous subfertility was also more frequent among sons of "high beef consumers" (P = 0.015). Sperm concentration was not significantly related to mother's consumption of other meat or to the man's consumption of any meat. CONCLUSIONS These data suggest that maternal beef consumption, and possibly xenobiotics in beef, may alter a man's testicular development in utero and adversely affect his reproductive capacity. 相似文献
95.
Thanapol Nongbua Essraa M. Al-Essawe Anders Edman Anders Johannisson 《Systems biology in reproductive medicine》2018,64(3):183-190
Variations in fertility between bulls with comparable sperm quality could be due to differences in their seminal plasma (SP). The aim of this study was to investigate the effect of adding bovine SP from bulls of known fertility to SP-free sperm samples. After removal of SP by Single Layer Centrifugation, resuspended sperm pellets were treated with SP from high or low fertility bulls at 0% (control), 1%, or 5% before freezing. Sperm quality was evaluated after thawing. Data were analyzed using Proc MIXED, SAS®. Bovine SP at 1% or 5% SP1 and SP5, respectively, decreased average path velocity, curvilinear velocity, and amplitude of lateral head displacement whereas wobble and linearity were increased. In addition, the proportion of spermatozoa with high mitochondrial membrane potential (MMP) was lowest for treatment with SP5 compared to SP1 and control. The proportion of SP did not affect other parameters of sperm quality. Thus, adding 5% bovine SP produced a favorable effect on some sperm velocity parameters but had an unfavorable effect on MMP. There were no differences in effect between SP from high and low fertility bulls.
Abbreviations: AI: artificial insemination; BCF: beat cross frequency; CASA: computer-assisted sperm analysis; IVF: in vitro fertilization; MMP: mitochondrial membrane potential; SLC: single layer centrifugation; SP: seminal plasma 相似文献
96.
目的:分析携带乙肝病毒(HBV)的不育男性的精液质量,探讨HBV感染对男性精液质量的影响。方法:选择2018年门诊初诊的782例不育男性,年龄25~35岁,根据HBV感染情况分为小三阳组(血清学检查乙肝表面抗原、e抗体、核心抗体阳性,n=286)和大三阳组(血清学检查乙肝表面抗原、e抗原、核心抗体阳性,n=230),以未感染者作为对照组(n=266),对上述3组进行精液常规、精子顶体酶活性及精子染色质结构分析,比较3组结果是否有差异。结果:①小三阳组精子浓度[(71.49±60.03)×10^6/ml]、前向运动精子百分率[(30.70±14.79)%]、精子活率[(42.67±17.23)%]、精子存活率[(81.07±10.19)%]、正常形态精子百分率[(5.72±3.47)%]均低于大三阳组[(88.20±82.62)×10^6/ml、(34.88±15.60)%、(45.77±16.58)%、(82.55±7.55)%、(6.93±4.45)%]和对照组[(89.29±53.80)×10^6/ml、(37.82±13.63)%、(48.16±14.03)%、(85.26±6.39)%、(7.27±4.43)%],除精子存活率以外差异均有统计学意义(P<0.05);大三阳组精子浓度、前向运动精子百分率、精子活率、精子存活率、正常形态精子百分率均低于对照组,其中前向运动精子百分率、精子存活率的差异有统计学意义(P<0.05);②小三阳组的精子顶体酶活性[(57.07±26.38)μIU/10^6精子]显著低于大三阳组[(63.03±28.75)μIU/10^6精子,P<0.05]和对照组[(78.00±33.49)μIU/10^6精子,P<0.01];大三阳组的精子顶体酶活性显著低于对照组(P<0.01);③小三阳组精子DNA碎片指数[DFI,(14.79±9.46)%]和高可染性[HDS,(9.62±6.20)%]均高于大三阳组[(12.95±7.29)%、(8.43±4.72)%]和对照组[(11.60±5.98)%、(8.41±4.59)%],差异有统计学意义(P<0.05);大三阳组的DFI和HDS均高于对照组,仅DFI的差异有统计学意义(P<0.05)。结论:HBV携带者的男性精液质量显著低于未感染者,HBV感染可能是引起男性生育力降低的原因之一。 相似文献
97.
Saleem Ali Banihani 《Andrologia》2020,52(6):e13592
Statins are lipid-lowering medications widely used to reduce the risk of cardiovascular diseases. Biochemically, they act by decreasing synthesis of cholesterol via inhibiting 3-hydroxy-3-methyl-glutaryl-coenzyme A reductase. Since 1992, various research studies have investigated the effect of statins on semen quality characteristics; however, to date, there is no collective summary to such effect. Here, we have systematically discussed and abridged all research studies published in Scopus, PubMed and Web of Science databases that are directly linking statin to semen fertility characteristics using the keywords “statin” versus “sperm” and “semen”. In summary, considering the animal studies, statins, in general, were found to ameliorate semen quality characteristics in reproductive detrimental conditions, while, in human males or in in vivo systems with normal reproductive conditions, in general, statins showed negative to blunt effects against semen quality characteristics, mainly sperm motility. However, further research studies, in particular human studies, in this specific research setting is still needed to approve these effects. 相似文献
98.
The declining trend of male fecundity is a major global health and social concern. Among numerous other confounding factors, variations in male fertility parameters in different regions have repeatedly been suggested to be influenced by geographic locations. The impact of overall lifestyle, behavioural patterns, ethnicity, work stress and associated factors upon health differ greatly between developed and developing countries. These factors, individually or in combination, affect male reproductive functions ensuing the discrepancies in semen qualities in connection with geographic variations. However, reports comparing semen characteristics between developed and developing countries are sparse. The present study finds its novelty in presenting a comparison in semen parameters of infertile men in the United States (n = 76) that fairly represents the population of a highly developed region and Iraq (n = 102), the representative of male populations of a developing region. Samples were collected and analysed according to WHO (WHO laboratory manual for the examination and processing of human semen, WHO; 2010) criteria by means of the Mann–Whitney test. The US population demonstrated lower sperm concentration, total count, and total and progressive sperm motility with a higher seminal total antioxidant capacity (TAC) as compared to the Iraqi population. This report encourages further investigations concerning the confounding factors leading to such alterations in semen qualities between these two geographic areas. 相似文献
99.
Effect of lansoprazole on DNA integrity of human spermatozoa and activity of seminal creatine kinase
Although lansoprazole (brand name Prevacid) is a commonly used dug to manage various acid-related gastrointestinal diseases, little is known about its effects on human semen quality and sperm parameters. Here, we aimed to investigate the effect of lansoprazole on DNA integrity of human spermatozoa and activity of seminal creatine kinase. DNA integrity of human spermatozoa was assessed by the Apo-Direct™ kit followed by flow cytometry. The activity of creatine kinase was measured by kinetic spectrophotometric method using commercially available kits following the International Federation of Clinical Chemistry recommendations. Lansoprazole at 3 µg/ml, after 1-hr incubation period, did not show any significant increase in fluorescein isothiocyanate fluorescence (p > .05) and hence on the content of DNA breaks of human spermatozoa. In addition, there was no significant change (p = .8113) in the activity of seminal creatine kinase by the effect of lansoprazole. In conclusion, lansoprazole at 3 µg/ml did not alter DNA integrity of human spermatozoa or activity of seminal creatine kinase after 1-hr incubation period. 相似文献
100.
Seyma Ozer Kaya Fatih Mehmet Kandemir Seyfettin Gur Mine Erisir Fulya Benzer Emre Kaya Gaffari Turk Mustafa Sonmez 《Andrologia》2020,52(1):e13439
The purpose of this study is to investigate the effects of L-arginine on spermatological parameters, seminal plasma nitric oxide levels and arginase enzyme activities. Fertile rams that are 2–3 years old and weighing 50–60 kg were used as material. The semen was collected by artificial vagina at 1st, 4th, 24th, 48th, 72nd, 96th and 120th hours for the control group before L-arginine administration. For treatment groups, L-arginine was administered intraperitoneally at a dose of 5 mg kg−1 bw−1 and semen was collected at the time point described for the control group. Spermatological characteristics of semen samples (semen volume, pH, sperm motility, concentration and abnormal sperm rate), seminal plasma nitric oxide levels and arginase enzyme activities were determined. Increased seminal plasma nitric oxide level (p < .01), seminal plasma arginase activity (p < .01), semen volume (p < .05), semen mass activity (p < .05), sperm motility (p < .05) and concentration (p < .01) and decreased abnormal sperm rate (p < .05 and p < .01) were observed by L-arginine administration. In conclusion, it may be concluded that L-arginine application in rams during the breeding season may have positive effects on rams' reproductive performance. 相似文献