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In this prospective study, we investigated the impact of SARS-CoV-2 infection on semen parameters in a cohort of men who had recently recovered from COVID-19. A total of 24 men who had recently recovered from mild COVID-19 were included in the study. Their semen parameters were normal before COVID-19 according to the World Health Organization 2010 reference values. Semen samples were collected from these participants in the recovery phases of COVID-19. To determine the effect of SARS-CoV-2 infection on semen parameters, the patients' pre-COVID-19 and post-COVID-19 semen analyses were compared. The mean age of the participants was 34.7 ± 6.4 years. The median interval between the positive nasopharyngeal swab test and obtaining semen samples was 111.5 (158) days. There was no significant difference in semen parameters before and after COVID-19 in terms of semen volume (p = .56), sperm concentration (p = .06), and progressive motility (p = .14). Total motility (p = .01) and total motile sperm count (p = .02) decreased significantly after SARS-CoV-2 infection compared to the pre-infection values. This study demonstrated that sperm motility and total motile sperm count were the semen parameters which showed a significant reduction in cases with a history of mild COVID-19.  相似文献   
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BackgroundArtificial insemination with the husband’s semen (AIH) is an economical and noninvasive method of infertility treatment. However, AIH’s pregnancy rate is much lower than in vitro fertilization (IVF) as its multiple and complex uncertainty factors. Semen quality has been one of the main factors which affect the pregnancy outcome of AIH.MethodsThe relevant parameters of 1,142 AIH cycles were retrospectively studied, including the general parameters and the semen quality parameters among clinical pregnancy, biochemical pregnancy, non-pregnancy group, age, infertility duration, infertility type, body mass index (BMI), cycle count, morphology in previously semen examination, and semen quality parameters on the day of AIH.ResultsThe statistically significant difference was only found on processed total non-forward and non-motile sperm count (N-TFMSC). The mean processed N-TFMSC in the biochemical pregnancy group was 6.37±4.27 million, significantly higher than the other two groups (vs. 4.40±3.15 million or vs. 4.48±3.60 million, P<0.05). The study was then divided into two groups according to processed N-TFMSC, Group 1 ≤5.0 million, and Group 2 >5.0 million. A statistical increase in biochemical pregnancy rate was observed when the processed N-TFMSC was >5.0 million (2.72% vs. 0.90%).ConclusionsProcessed N-TFMSC may be one of the independent factors on AIH’s outcome; it should be given equal attention the same as processed total forward motile sperm count (TFMSC).  相似文献   
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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   

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目的:分析和鉴定王不留行、决明子、酸枣仁3种药材炒制前后脂肪油类成分的变化,为探索种子类药材"逢子必炒"的炮制机制奠定基础。方法:以石油醚为溶剂,采取索氏提取器提取脂肪油,甲酯化后用气相色谱-质谱联用技术(GCMS)分离、鉴定其组成和相对质量分数。HP-5毛细管柱(0.25 mm×30 m,0.25μm),载气99.999%高纯氮,流速1 mL·min~(-1),采用程序升温方式(初始温度50℃,以5℃·min~(-1)升至170℃,停留4 min,5℃·min~(-1)升至190℃,0.5℃·min~(-1)升至200℃,10℃·min~(-1)升至240℃,保持4 min),进样量1μL,电子轰击离子源(EI),离子源温度220℃,电子能量70 eV。结果:王不留行、决明子、酸枣仁3种药材生品脂肪油提取率分别为3.34%,6.16%,20.66%,炒制品脂肪油提取率分别为4.67%,7.40%,26.35%。王不留行生品鉴定出7个化合物,炒制品鉴定出10个化合物;决明子生品鉴定出8个化合物,炒制品鉴定出9个化合物;酸枣仁生品鉴定出10个化合物,炒制品鉴定出14个化合物。结论:炒制能提高脂肪油的提取效率,炒制后3种药材脂肪油的组成出现了一些共性变化。  相似文献   
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The effects of freezing technique and thawing protocol on thawed semen viability and fertility were studied. Ejaculates from 5 stallions (= 25) were frozen by conventional or a fast‐freezing technique. Frozen semen was thawed by two thawing protocols (37 °C 30 s?1 or 75 °C 7 s?1). Thawed semen was evaluated by progressive motility, vigour, morphology and plasma membrane integrity. Mares (= 25) were inseminated with 300 (= 11) or 150 (= 14) million spermatozoa. A greater (P < 0.05) vigour and progressively motile spermatozoa were detected, respectively, at thawing and after 20 min post‐thawing in the fast‐freezing technique than in the conventional one. Plasma membrane integrity was also greater (P < 0.05) in semen frozen with the fast‐freezing technique. Semen viability was not affected by thawing protocol. Pregnancy rate using the fast‐freezing technique was 76% (19/25), and did not differ (P > 0.05) between insemination doses. We concluded that the 150 million progressively motile spermatozoa per dose using a deep‐horn insemination maximises the use of equine semen. The fast‐freezing technique, as compared to the conventional one, efficiently preserves the viability and fertilising capacity of spermatozoa, indicating a new method to improve the fertility of frozen equine semen.  相似文献   
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