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1.
The excessive generation of reactive oxygen species (ROS) by abnormal spermatozoa and contaminating leukocytes has been defined as one of the few etiologies for male infertility. Administration of antioxidants in patients with ‘male factor’ infertility has begun to attract considerable interest. The main difficulty of such an approach is our incomplete understanding of the role of free radicals in normal and abnormal sperm function leading to male infertility. Mammalian spermatozoa membranes are very sensitive to free radical induced damage mediated by lipid peroxidation, as they are rich in polyunsaturated fatty acids. Limited endogenous mechanisms exist to reverse these damages. ROS attacks the fluidity of the sperm plasma membrane and the integrity of DNA in the sperm nucleus. ROS induced DNA damage accelerate the germ cell apoptosis. Unfortunately spermatozoa are unable to repair the damage induced by excessive ROS as they lack the cytoplasmic enzymes required to accomplish the repair. Assessment of such oxidative stress status (OSS) may help in the medical treatment. Treatment strategies must be directed toward lowering of ROS levels to keep only a small amount necessary to maintain normal cell function.  相似文献   

2.
Defective sperm function is the most common cause of infertility. A prospective study was carried out to correlate the concentration of nitrite (the stable metabolite of nitric oxide) in seminal plasma with leukocytospermia, and sperm membrane integrity. Total Fifty-seven normozoospermic subjects with and without leukocytospermia visiting the Infertility clinic at KH and MRC, Karad, were included in the present study. Semen samples were checked for sperm concentration, total sperm count, sperm motility, seminal leukocyte concentration and sperm membrane integrity as Hypoosmotic Swelling Test. Similarly the concentration of nitrite in seminal plasma was measured by Griess reaction and total antioxidant power measured as ferric reducing ability of plasma. The concentration of nitrite in seminal plasma was found to be raised with significantly increased leukocyte concentration in semen. Also significantly lowered levels of total antioxidant power along with defective sperm function was observed. Our results suggest that supplementary treatment of antioxidants with antibiotic for leukocytospermic infertile male patients may improve the sperm membrane integrity.  相似文献   

3.
张云 《大众科技》2016,(5):96-97
随着"全面二胎"政策的开放,群众对不孕的关注不断提高。生活节奏的加快,不孕的患者也越来越多。中医药在治疗不孕症方面有着丰富的经验,且疗效优于西药,给患者带来的经济和精神压力较小,能有效增加患者的妊娠率,安全可靠。  相似文献   

4.
The objective of this study was to evaluate acrosin activity in spermatozoa of infertile Nigerian men and to compare with those of the fertile men. The acrosin activity was evaluated using the Acroscreen reagent kit. The acrosin activity of the fertile men was 40.7±5.2 mIU/106 sperm (range 30.1–51.3) and those of the infertile men was 22.4±8.33 mIU/106 sperm (range 5.7–39.1). The difference in the mean was statistically significant (P<0.001). There was a subpopulation of the infertile men who had their acrosin activity within normal range of the fertile men, 32.9±1.57 mIU/106 sperm. But the difference in the mean was statistically significant (P<0.001). Acrosin activity decreased with increased morphological changes in the spermatozoa. It is concluded that acrosin activity in the infertile Nigerian men is significantly lower than that in the fertile men. Acrosin activity may also be affected by morphological changes in the spermatozoa.  相似文献   

5.
The objective of the study was to estimate the serum concentrations of oxidative stress markers-lipid hydroperoxide (MDA-Malondialdehyde), lactate dehydrogenase (LDH), nitrite; and ferric reducing antioxidant power (FRAP) — a measure of total antioxidant capacity in serum. Serum nitrite levels were high in fertile women than in infertile women (p<0.001), whereas MDA was high in infertile women than in fertile group (p<0.018). On classifying the entire group of women with infertility based on the etiology, serum MDA and LDH levels were higher in women with infertility due to unexplained factor than in women with other causes contributing to infertility compared to controls (p<0.001, p<0.02). A positive correlation among serum prolactin and nitrite suggested that hyperprolactinemia could contribute to infertility by inducing oxidative damage. Serum FRAP levels showed no significant difference in the groups studied. Lipid peroxidation was high in women with unexplained infertility which may be due to hyperprolactinemia.  相似文献   

6.
There is growing evidence that damage to spermatozoa by reactive oxygen species play a key role in male infertility. The aim of this study was to assess seminal plasma free 8-Isoprostane levels in men with asthenozoospermia, asthenoteratozoospermia and oligoasthenoteratozoospermia compared to normozoospermic males and its correlation with seminal parameters. The case group consisted of men with asthenozoospermia (n=15), asthenoteratozoospermia (n=16) and oligoasthenoteratozoospermia (n=15). The control group consisted of 16 males with normozoospermia. After Purification of Free 8-Isoprostane by affinity column, its concentration was measured by enzyme immunoassay method. Free 8-Isoprostane evaluation showed significantly greater values in the total case group (n=46) versus control group (18.23±3.56 vs 2.6±0.38 ng/ml). In each case group free 8-Isoprostane also showed a significant increasing compared to normozoospermic males. Free 8-Isoprostane showed an inversely significant correlation with sperm motility and sperm morphology. Lipid peroxidation could have significant role in etiology of sperm abnormalities. Measurement of 8-Isoprostane can be used as a specific biomarker for assessing lipid peoxidation in sperm.  相似文献   

7.
Methylenetetrahydrofolate reductase (MTHFR) is a critical enzyme of folate pathway and required for DNA synthesis and methylation. MTHFE C677T polymorphisms is reported as risk factors for various diseases and disorders like birth defects, metabolic, neurological, psychiatric disorders, and cancers. Several studies have investigated association between the MTHFR C677T polymorphism and male infertility. To assess the risk associated with MTHFR C677T polymorphism in Asian population, a meta-analysis was performed. Included articles were collected from the following electronic databases: PubMed, Google Scholar, and Science direct up to March 2015. Risk was estimated as pooled odds ratios (ORs) with confidence intervals (CIs) for assessment. Seventeen case–control studies involving 4392 breast infertile males and 3667 fertile males were found suitable for the inclusion in the present meta-analysis. Results showed that the C677T polymorphism was significantly associated with male infertility in Asian population using all the five genetic models (ORT vs. C (allele contrast model) = 1.86, 95% CI 1.7–2.0; ORTT vs. CC (homozygote model) = 1.96, 95% CI 1.67–2.30; ORCT vs. CC (co-dominant model) = 1.40, 95% CI 1.18–1.62; ORTT+CT vs. CC (dominant model) = 1.53, 95% CI 1.30–1.77; ORTT vs. CT+CC (recessive model) = 1.67, 95% CI 1.44–1.92). In conclusion, results of present meta-analysis strongly supported an association between C677T polymorphism and male infertility in Asians.  相似文献   

8.
经济与管理类大学生课堂参与研究--以太原科技大学为例   总被引：1，自引：0，他引：1  
随着高等教育扩招政策的实施,高校教育质量出现下滑,这一问题引起了越来越多人们的重视。于此同时,大学生的课堂参与也出现下滑趋势,课堂参与对于教育质量的影响很大。以经济与管理类大学生作为调查对象,研究了大学生课堂参与的现状和影响因素,并提出针对性的解决对策。希望通过提高大学生的课堂参与度,进而提高高等教育的教育服务质量。  相似文献   

9.
Cystic fibrosis is a common autosomal recessive disorder usually found in population of white Caucasian descent. Now it is well documented the presence of CF disease in India with the advancement of laboratory testing. As once it was thought non existence of this disease in our population. Most of the phenotype of CF disease was in accordance of western population. Genetic analysis of CFTR gene in Indian CF patients revealed that most common mutation was delta F508 mutation. However, it was less than Caucasian population. CFTR mutations are also a causative factor in the pathogenesis of male infertility due to obstructive azoospermia. There are two most common mutation viz. IVS8-T5 and delta F508 which are responsible for congenital absence of vas deferens in male infertility patients. Elevated levels of sweat chloride at two occasions along with the presence of two mutations in CFTR gene was gold standard method for diagnosis of CF disease. It is noteworthy here that due to magnitude of Indian population, the total CF disease load would be more than many European countries. Clinical data demonstrate the prevalence of both classical and genetic form of CF in India.  相似文献   

10.
综述了科技期刊编辑部自行研制计算机现代化信息管理的主要进展、使用特点和应用现状，结合研究与实践所取得的阶段性成果和产生的新认识、新经验，提出了应该继续普及和更加完善科技期刊现代化计算机管理的建议及推广思路，旨在推进我国科技期刊编辑部的稿件管理等工作尽快达到国内外先进管理水平。  相似文献   

11.
用DAPI荧光染色方法检测了旋花科4属4种植物——空心菜Ipomoea aquatica Forsk. 、茑萝 Qua- moclit pennata (Desr．)Boj．、月光花 Calonyction aculeatum(L．)House和日本菟丝子Cuscuta japonica Choisy 中生殖细胞和精细胞中细胞质DNA存在的状况。证明除日本菟丝子外，其余3种植物的雄性细胞中都 存在细胞质DNA。此外，在我们曾研究过的5种旋花科种植物的生殖细胞和精细胞中亦显示含有细胞质 DNA，因而可认为这是旋花科较普遍的特性，日本菟丝子精细胞中缺少细胞质DNA，可作为—个新的胚胎学证据，支持此属从旋花科分出独立为菟丝子科。  相似文献   

12.
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13.
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14.
Epithelial ovarian cancer accounts for more than 90% of ovarian tumours and continues as a leading cause of death from gynaecological malignancies. It is often difficult to differentiate a benign ovarian mass from malignant ones. Invasive histopathological biopsy is used as the gold standard diagnostic tool to diagnose cancer in patients with ovarian mass. A wide spectrum of Biomarkers were tried in various studies to develop a non invasive diagnostic tool, out of which HE4 and CA 125 remain the only clinically useful biomarker. Consequently various Biomarker based algorithms i.e. Risk of Malignancy Index, risk of ovarian cancer algorithm, OVA1, risk of malignancy algorithm were generated that have been developed to assess the risk of a mass being malignant. These algorithms help in timely triage of patients. Recently in 2016 FDA cleared Ova1 test (OVERA) with CA 125-II, HE4, apolipoprotein A-1, FSH, and transferring (Sensitivity 91% and Specificity 69%) as a referral or Triage test in patients presenting with ovarian mass. Combination of protein and circulating Micro RNA analysis in blood, could provide a comprehensive screening and diagnostic panel, in management of patients presenting with ovarian mass in one clinical setting.  相似文献   

15.
In sexual assault cases, forensic samples are a mixture of sperm from the perpetrator and epithelial cells from the victim. To obtain an independent short tandem repeat (STR) profile of the perpetrator, sperm cells must be separated from the mixture of cells. However, the current method used in crime laboratories, namely, differential extraction, is a time-consuming and labor-intensive process. To achieve a rapid and automated sample pretreatment process, we fabricated a microdevice for hydrodynamic and size-based separation of sperm and epithelial cells. When cells in suspension were introduced into the device''s microfluidic channels, they were forced to flow along different streamlines and into different outlets due to their different diameters. With the proposed microdevice, sperm can be separated within a short period of time (0.5 h for a 50-μl mock sample). The STR profiles of the products in the sperm outlet reservoir demonstrated that a highly purified male DNA fraction could be obtained (94.0% male fraction). This microdevice is of low-cost and can be easily integrated with other subsequent analysis units, providing great potential in the process of analyzing sexual assault evidence as well as in other areas requiring cell sorting.  相似文献   

16.
Myasthenia gravis (MG) is an autoimmune disease that results from antibody mediated damage of Acetylcholine receptor (AChR) at the neuromuscular junction. The autoimmune character of MG and pathogenic role of AChR antibodies have been established by several workers i.e., the demonstration of anti-AChR antibodies in about 90 % of MG patients. It has been demonstrated that patients with MG also have antibodies against a second protein named presynaptic membrane receptor (PsmR), which is identified by utilizing β-Bgtx, a ligand which binds to PsmR. Using β-Bgtx Sepharose 4B affinity matrix, the PsmR was purified from different regions of human cadaver brain by affinity chromatography. Purified receptor was characterized both by biochemical and immunological procedures. PsmR purified from different regions of the brain shows a specific activity of 0.37 ± 0.01, 0.39 ± 0.02 and 0.43 ± 0.005 nM/ μg of protein in Parietal lobe, Occipital lobe and Frontal lobe respectively. The affinity purified PsmR from the brain of 87 and 68 kd (parietal lobe, occipital lobe and frontal lobe) shows immunoreactivity with myasthenic sera. These findings suggest that PsmR from brain is another antigen against which autoantibodies are developed in Myasthenia gravis patients. Upon treatment with various enzymes we concluded that PsmR from brain is a glycoprotein in which the immunoreactivity resides in the carbohydrate as well as the peptide epitopes. In conclusion the PsmR is another antigen against which autoantibodies are formed in different regions of brain. These can be used as a diagnostic tool for detecting antibodies in the sera or cerebrospinal fluid of MG patients.  相似文献   

17.
This study evaluated the extent of oxidative stress by measuring malondialdehyde and ascorbic acid in the seminal plasma of human subjects with different fertility potential. Semen samples from 148 subjects were evaluated (48 normozoospermics, 34 oligoasthenoteratozoospermics, 34 asthenoteratozoospermics and 32 azoospermics). malondialdehyde level was found to be significantly higher in the abnormal groups (oligoasthenoterato and asthenoterato-zoospermics) than normozoospermics (P < 0.01). Negative correlation was also found between malondialdehyde level, sperm concentration, sperm motility and sperm morphology. Level of ascorbic acid was found to be significantly higher in normozoospermics than other abnormal groups (P < 0.01). It was found to be correlated positively with all seminogram parameters and negatively with malondialdehyde level. The study revealed that, excess lipid peroxidation reflected by high malondialdehyde level with reduced ascorbic acid in human seminal plasma is associated with poor semen quality where as ascorbic acid content has positive correlation with fertility potential.  相似文献   

18.
Urine may be a waste product, but it contains an enormous amount of information. Well-standardized procedures for collection, transport, sample preparation and analysis should become the basis of an effective diagnostic strategy for urinalysis. As reproducibility of urinalysis has been greatly improved due to recent technological progress, preanalytical requirements of urinalysis have gained importance and have become stricter. Since the patients themselves often sample urine specimens, urinalysis is very susceptible to preanalytical issues. Various sampling methods and inappropriate specimen transport can cause important preanalytical errors. The use of preservatives may be helpful for particular analytes. Unfortunately, a universal preservative that allows a complete urinalysis does not (yet) exist. The preanalytical aspects are also of major importance for newer applications (e.g. metabolomics). The present review deals with the current preanalytical problems and requirements for the most common urinary analytes.  相似文献   

19.
王志敏 《科教文汇》2021,(13):48-49
文章以扎兰屯职业学院推行实施线上教学为例,从制定线上教学管理制度、指导教师选择教学平台进行资源整合,到学生对教师线上教学满意度的调研,采取的一系列措施保障了线上教学的有效实施。在线上教学的实施过程中,有大力推广的经验,也有亟待解决的问题,更是开启了对今后"线上+线上"混合式教学模式的探究,从而提升高职学生的人才培养质量。  相似文献   

20.
技术事实的查明是知识产权诉讼案件中难以回避的问题,新设置的技术调查官制度为破解相关技术难题提供了保障,有助于发掘知识产权诉讼的案件真实,进而提升纠纷解决质效。在司法实践中,技术调查官制度遭遇了选任与管理不明、参与诉讼活动的程序不规范、与司法鉴定制度不协调等困境。为克服上述不足,有必要从选任标准与管理办法的构建、诉讼程序的法定和公开、从内而外协调与司法鉴定制度的关系等三个层面加以完善,充分发挥该制度在查明案件技术事实方面的积极性,以助益知识产权诉讼在科技创新领域有效发挥司法保障职能。  相似文献   

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