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1.
Nonsperm cells in human semen and their relationship with semen parameters   总被引:3,自引:0,他引:3  
The prevalence and clinical significance of leukocytes (WBC) and immature germ cells in semen is currently a matter of controversy. The aim of this work was to assess the prevalence of leukocytospermia in semen samples from Venezuelan men and its possible effects on sperm parameters. The concentration of WBC and round cells (RC) was evaluated in 118 semen samples from 19 fertile subjects (group 1), 62 infertile patients (group II), and 37 men with varicocele (group III). Semen WBC concentration was assessed by peroxidase assay. Twenty-six (22%) of the total samples had more than 10 WBC/mL semen. Twenty of the infertile men had leukocytospermia (32%) compared with 16% in the fertile group and 8% in the varicocele group. Semen RC concentration was lower than 5 x 10(6)/mL in all groups but, in groups II and III was significantly higher compared with group I. Infertile men had the highest WBC concentration. WBC concentration was negatively correlated with progressive motility, percentage of morphologically normal sperm, and hypoosmotic swelling test in infertile men but not in the varicocele group. In this group a negative correlation was obtained between immature germ cells and normal sperm morphology. The data show that leukcytospermia occurs frequently in infertile patients and is associated with poor semen quality parameters. In contrast, in men with varicocele, the increased number of immature germ cells might play a pivotal role in the pathogenesis of abnormal spermatozoa.  相似文献   

2.
Varicocele occurs in approximately 15% to 20% of the general male population and it is the most common cause of poor semen production and decreased semen quality. It has been demonstrated that patients with varicocele have a significantly higher DNA fragmentation index (DFI) and spermatozoa with nuclear anomalies than healthy fertile men. Therefore, the aim of this study was to evaluate sperm chromatin integrity in these patients. Sixty men referring to the andrology laboratory were categorised into three different groups: 20 infertile men with varicocele, 20 infertile men with abnormal semen parameters and 20 fertile men who had normal spermatogram were considered as control group. Semen analysis was performed according to WHO criteria. To evaluate sperm chromatin quality and DNA integrity, after fixation of sperm smears, aniline blue, toluidine blue, chromomycin A3 and acridine orange staining were applied in three groups. The slides were analysed by light and fluorescent microscopy and to determine the percentage of mature or immature spermatozoa, 200 spermatozoa were counted in each slide. The results showed that the rates of aniline blue-reacted spermatozoa were significantly higher in infertile and varicocele patients than in the normal group ( P  < 0.001). In addition, with regard to chromomycin A3, acridine orange and toluidine blue staining, there was a significant difference between the three groups ( P  < 0.001). The results showed that the varicocele samples contain a higher proportion of spermatozoa with abnormal DNA and immature chromatin than those from fertile men as well as infertile men without varicocele. Therefore, varicocele results in the production of spermatozoa with less condensed chromatin and this is one of the possible causes of infertility due to varicocele.  相似文献   

3.
Increased DNA fragmentation is found in sperm from infertile men. Varicocele is an important cause of male infertility, even though it is present in 15% of men who father children. Semen analysis does not always identify infertility in these patients. Sperm motility is strongly correlated with male fertility potential. The goal of this study was to determine the correlation between apoptosis and kinematics in the ejaculated spermatozoa of patients affected by varicocele. Fresh semen samples were obtained from 30 patients with varicocele and 15 fertile controls. These samples were compared using computer-assisted semen analysis and were assayed to determine the degree of sperm apoptosis. The apoptotic index (AI) was calculated by dividing the number of terminal deoxynucleotidyl transferase-mediated deoxyuridine-5'-triphosphate nick end labeling (TUNEL) stained spermatozoa by the total number of Hoechst 33258-stained sperm cells for 300 sperm. Five microscopic fields were analyzed to obtain 5 AIs for each individual. Results demonstrated no significant difference in semen quality and sperm motion characteristics; however, a significantly higher AI (23.05% +/- 4.07%: mean difference +/- SE, 95% CI, 15.06%-31.03%, P <.0001) was identified in the varicocele group than in the fertile controls. We concluded that sperm apoptosis does not seem to correlate with semen quality and sperm kinematics and that apoptosis is increased in ejaculated spermatozoa in patients with varicocele compared to normal fertile men.  相似文献   

4.
The objective of the present study was to evaluate the association between the expression of sperm mannose-ligand receptors and sperm morphology. Sperm samples were obtained from 45 men, 30 fertile sperm donors and 15 infertile men. Sperm concentration, motility and morphology were evaluated and then incubated with control medium (Ham's F-10 + 1% HSA) for 4 h. Expression of mannose-ligand receptors was evaluated by mannosylated-BSA-FITC (subdivided into 3 patterns: I, for uncapacitated sperm; II, for capacitated; and III, for acrosome-reacted sperm). The mean (+/- SE) frequencies of sperm cells of the total sperm population that expressed patterns I, II, and III were 88 +/- 2.1%, 7 +/- 1.6%, and 5 +/- 0.8%, respectively, for fertile men, and 90 +/- 2.1%, 7 +/- 1.3%, and 3 +/- 0.5%, respectively, for infertile men. The rate of pattern III expression of mannose-ligand receptors was significantly higher in the fertile group compared to the infertile patients (p <.01). A poor but significant correlation was observed between the rate of pattern III and the percentage of normal-forms sperm cell in the ejaculate (r =.35, p =.018). Fertile sperm samples express more advanced patterns of mannose-ligand receptors compared to infertile men. This phenomenon is related to the morphology of human sperm cell in the ejaculate more than to any other basic sperm characteristics.  相似文献   

5.
This retrospective study evaluated the correlation between the sperm DNA integrity results and infertile male age or sperm motility in 654 infertile men undergoing infertility evaluations from 2013 to 2016. The correlation between the results of sperm DNA integrity and male age was positive, while a negative correlation was detected between sperm DNA integrity and sperm motility in all subjects. According to age (≤30, 30–35 and ≥35), men with normozoospermia or abnormal semen parameters were, respectively, divided into groups 1, 2 and 3, or groups A, B and C. The sperm DNA fragmentation index (DFI) and DFI abnormality rates in groups 3 and C were highest among their respective cohorts. But they were not significantly different between groups within the same age range. Statistically significant differences were found in male age, progressive motility, as well as total motility between patients with normal DFIs and those with abnormal DFIs in group C, but not in group 3. Older (≥35 years) infertile men have increased sperm DNA fragmentation, independent of conventional semen parameters. Male age is more critical to sperm DNA integrity than routine semen parameters.  相似文献   

6.
The present study was carried out on semen samples of human fertile and infertile subjects, teratozoospermics (TZs) and idiopathics (IDs), with neat semen and sperm prepared by swim up or Percoll density gradient centrifugation procedures. Sperm morphology analysis revealed that only head and midpiece defects in TZs and IDs were significantly (P < 0.001) higher compared to fertile subjects. Infertile subjects indicated significantly higher (P < 0.001) sperm DNA damage compared to fertile subjects. Fertile subjects with sperm prepared from neat and Percoll density gradient centrifugation exhibited a comet tail DNA percentage of 20% and 15%, respectively. The TZs and IDs infertile subjects had higher levels of comet tail DNA of 33% and 25% and 25% and 19%, respectively. A significant (F = 24.01; P = 0.0059) decrease in mean comet head DNA percentage or sperm DNA integrity was observed in neat samples from fertile and infertile subjects by Repeated Measures ANOVA. In Percoll prepared samples from fertile, TZs, and IDs, there was a significant increase in sperm DNA integrity. Similarily, there was a decrease in abnormal sperm morphology in swim up and Percoll prepared sperm compared to neat samples. The Percoll density gradient centrifugation procedure yields sperm with an increase in sperm DNA integrity relative to swim up. Sperm DNA damage of TZs with both sperm preparation methods was significantly (P < 0.01) higher when compared to fertile and IDs. But the level of DNA damage was higher in IDs compared to fertile subjects. Compared to the other methods tested, the Percoll method yielded sperm with improved DNA integrity. In conjunction with semen analysis, the assessment of nuclear integrity improves the characterization of the semen sample and may be used as a tool for allocating the patients to specific assisted reproductive treatments.  相似文献   

7.
The aim of this study was to explore sperm chromosomal aneuploidy and DNA integrity in infertile patients with spinal cord injury (SCI). Semensamples were collected from 12 infertile menwith SCI by percutaneous vasal sperm aspiration (PVSA) and from 14 male SCI patients by penile vibratory stimulation (PVS). These semen samples as well as samples from 16 donors were analyzed using the hypo-osmotic swelling (HOS) test, the sperm chromatin dispersion test, terminal deoxynucleotidyl transferase-mediated terminal uridine nick-end labeling assay, and multicolor fluorescence in situ hybridization with probes specific for the chromosomes 13, 18, 21, X, and Y. There were significant differences in the percentages of motile sperm, normal morphologic sperm, normal HOS/eosin staining, and sperm DNA fragmentation between the infertile men with SCI and the control group (P < .05 and P < .01). The sperm forward motility was significantly greater in the PVSA group than in the PVS group (P < .01). The number of round cells per milliliter of semen obtained from the 14 SCI patients by PVS was between 1 million and 12 million. The rate of sperm DNA fragmentation, as identified by the sperm chromatin dispersion test, was higher in the PVS group than in the PVSA group (P < .05). The aneuploidy rates for the SCI patients were 1.5- to 1.6-fold higher for chromosomes 13, 18, and 21, and were 2.3- to 2.4-fold higher for chromosomes X and Y than for patients in the control group (P < .001). These results suggest that for men with SCI, the semen quality is poorer, the prevalence of abnormal HOS/eosin staining is greater, and sperm DNA fragmentation and sperm chromosomal aneuploidies are seen at a higher rate compared with healthy, fertile, and normospermic men.  相似文献   

8.
Oxidative stress is a well-established cause of male infertility, with reactive oxygen species (ROS) causing infertility principally by impairing sperm motility and DNA integrity. Currently, most clinics do not test their infertile patients for the presence of oxidative stress because the available tests are expensive or difficult to perform. As antioxidant therapy may improve sperm DNA integrity and pregnancy outcomes, it has become apparent that there is an unmet clinical need for an inexpensive and easy-to-perform assay to identify sperm oxidative stress. The aim of this study was to develop a standardized protocol for performing a photometric nitro blue tetrazolium (NBT) assay for the measurement of seminal ROS production via production of coloured formazan, whilst correlating these results with impaired sperm function (motility and DNA integrity). Semen samples from 21 fertile and 36 male aetiology infertile men were assessed for ROS production (NBT assay), sperm DNA integrity (TUNEL), apoptosis (Annexin V) and sperm motility. Infertile men's semen contained on average fourfold higher levels of ROS than fertile men. The production of ROS by sperm was positively correlated with sperm DNA fragmentation and apoptosis, whilst being negatively correlated with sperm motility. Receiver-operating characteristic plot analysis established a cut-off point of 24 μg formazan/107 sperm having a sensitivity of 91.7% and a specificity of 81% for determining the fertility status of an individual. This study has been successful in establishing a standardized protocol for performing a photometric seminal NBT assay that has significant clinical utility in identifying men with impaired fertility because of oxidative stress.  相似文献   

9.
计算机职业男性不育患者精液分析   总被引:7,自引:2,他引:5  
目的:探讨计算机职业与男性精液质量的相关性。方法:对兰州军区乌鲁木齐总医院男性不育门诊诊疗的不育男性224例,其中长期接触计算机职业的(计算机组)118例、不接触计算机职业的(非计算机组)106例与125例正常生育男性(正常对照组)精液从精液量、液化时间、精子总数、精子密度、精子活力、精子活率等参数方面进行分析。不育计算机组按每天接触计算机累计时间分为0~5h/d36例,6~10h/d44例,>10h/d38例。结果:①不育计算机组、不育非计算机组与正常对照组比较,精液量、精子密度、精子活力、精子活率等参数显著降低(P<0.05~0.01),液化时间延长(P<0.01)。②不育计算机组与不育非计算机组相比,精液量、精子活力、精子活率显著降低(P<0.05)。③计算机不同使用组:>10h/d组与0~5h/d和6~10h/d两组比较,精子密度、精子活力、精子活率均显著降低(P<0.05~0.01),而0~5h/d和6~10h/d两组精液各参数之间差异无显著性(P>0.05)。结论:①计算机职业可引起男性精液质量异常;②长时间使用计算机(>10h/d)可能是引起男性不育的原因之一。  相似文献   

10.
It remains unknown whether human papillomaviruses (HPVs) in semen affect sperm DNA integrity. We investigated whether the presence of these viruses in semen was associated with an elevated sperm DNA fragmentation index. Semen samples of 22 normozoospermic patients undergoing infertility treatment, nine fertile donors and seven fertile men with a risk of HPV infection (genital warts or condylomas) were included in the study. The samples were examined by an INNO‐LiPA test PCR‐based reverse hybridisation array that identifies 28 types of HPVs as simple or multiple infections. Sperm DNA integrity was determined by sperm chromatin dispersion assay (SCD). Our preliminary findings demonstrate an increase in HPV infection in infertile men with respect to fertile men. However, the sperm DNA fragmentation index was not increased in semen containing these viruses.  相似文献   

11.
目的:应用荧光染料SYBR-14/PI双色标记法进行流式细胞术检测不育患者精子质膜完整性,分析吸烟对精子质膜完整性的影响并探讨其临床意义。方法:收集202例男性精液标本,其中132例为本院就诊男性不育患者,分为大烟量组(n=68)与小烟量组(n=64),正常生育男性为正常对照组(n=70)。通过计算机辅助精液分析系统进行精液常规分析。精液标本经PBS洗涤处理后用荧光染料SYBR-14/碘化丙锭(PI)双染后上流式细胞仪分析,用SYBR-14+/PI-(绿)表示质膜完整精子(PMI);SYBR-14-/PI+(红)表示质膜破损而坏死的精子;SYBR-14+/PI+(绿,红)表示正处于由活到死过度状态的精子。检测精子质膜完整性,并对精子质膜完整性与部分精液参数做相关性分析。结果:大烟量组与小烟量组质膜破损的坏死精子(SYBR-14-/PI+%)、过渡态的精子(SYBR-14+/PI-%)与正常对照组存在显著差异(P<0.01或0.05)。大烟量组SYBR-14+/PI-%明显低于小烟量组,SYBR-14-/PI+%明显高于小烟量组。所有202例标本SYBR14+/PI-%与精子活动率呈显著正相关(r=0.938,P=0.000)。结论:应用流式细胞术SYBR-14/PI双染法能快速、准确地检测精子质膜完整性。吸烟会导致精子质膜完整性下降,引起精子活力下降,可能是导致男性不育的重要原因之一。  相似文献   

12.
Lead and copper concentrations were determined by atomic absorption spectroscopy in semen from 18 fertile and 172 infertile men. Significant correlations between copper concentrations in semen and sperm concentration (r = 0.32, P less than 0.001), percentage progressive motility (r = 0.23, P less than 0.005) and normal morphology (r = 0.22, P less than 0.005) were observed, while no such correlation existed for lead. However, semen copper concentrations of infertile men (194.99 +/- 5.70 micrograms l-1) and fertile men (183.39 +/- 14.37 micrograms l-1) did not differ significantly. Mean lead concentration in semen of fertile men was 11.18 +/- 0.62 micrograms l-1 and significantly higher than lead concentration in semen of fertile men (5.61 +/- 0.53 micrograms l-1, P less than 0.006). Reinvestigation of 18 infertile men after 2 years showed a significant drop of lead concentrations in semen from 17.31 +/- 1.41 to 6.94 +/- 1.32 micrograms l-1 (P less than 0.0002), which might be related to the decreasing use of leaded petrol in the Federal Republic of Germany.  相似文献   

13.
BackgroundMale-factor infertility plays a role in approximately 50% of infertile couples. In at least 30% of cases, repeated standard semen analyses of the male partner of an infertile couple reveal normal results. When diagnostic work-up of the female partner is also normal, they are classified as idiopathic. The objective of this study was to evaluate the levels of sperm nuclear DNA fragmentation in a population of infertile men with normal standard semen parameters and to compare their results with those from men who had abnormal semen parameters, as well as with a control group of fertile men.MethodsSemen samples were obtained from 202 infertile men and 30 fertile donors. Standard semen analysis was performed according to the World Health Organization guidelines. Flow cytometry has been extensively used to study sperm DNA fragmentation and the results are expressed as the percentage of sperm DNA fragmentation index (DFI).ResultsOf the 202 patients, 48 (23.8%) had normal standard sperm parameters, while 154 (76.2%) had an abnormality in one or more of these parameters. DFI in infertile men with normal sperm parameters was significantly higher than in fertile donors (p = 0.03), but not significantly different from infertile men with abnormal sperm parameters (p = 0.10). There were statistically significant negative correlations between DFI and the percentage of motile sperm from infertile men with abnormal and normal semen parameters, but not in fertile donors (r = ?0.26, p = 0.001 and r = ?0.48, p = 0.0001, respectively).ConclusionSperm from infertile men with normal standard sperm parameters may have significant levels of DNA fragmentation that are comparable to levels in infertile men with abnormal sperm parameters. Sperm DNA fragmentation analysis is an independent test of sperm quality and has an important diagnostic value in the evaluation of male infertility.  相似文献   

14.
The phospholipid and fatty acid composition of sperm was studied in 8 healthy and 16 infertile men. Infertile men randomly formed from the patients with normal semen parameters according to WHO criterion. Therefore, all semen parameters of infertile patients were similar to the same characteristics of the semen of healthy men, except the abnormal forms. The amount of abnormal forms in infertile men was significantly higher than in healthy men. Sperm from infertile men show a drastic loss of phosphatidyl ethanolamine. At the same time, the significant increase of phosphatidyl serine in the sperm and seminal plasma of sterile patients was found. Lysophosphatidyl serine in the sperm of the infertile men was detected. Fatty acid composition of the semen of infertile men was altered. The levels of stearic and n-3 polyunsaturated fatty acids (eicosopentaenoic and docosahexaenoic acids) was dramatically lowered, but the values of some n-6 polyunsaturated fatty acids (linolenic and docosatetraenoic) acids increased. There was significant positive correlation between docosahexaenoic acid and sperm motility (r = .82, p < .001) and negative correlation between linolenic acid and spermatozoa motility (r = -0.58. p < .05). Infertility of men with normal semen quality can originate from the disorder of sperm lipid metabolism. The drastic loss of phosphatidyl ethanolamine and n-3 polyunsaturated fatty acids with simultaneous enhancement of phosphatidyl serine and some n-6 polyunsaturated fatty acids in sperm could be an important cause of male infertility.  相似文献   

15.
流式细胞计检测人精子顶体及其与精液其他参数的关系   总被引:1,自引:0,他引:1  
运用流式细胞计及人精子顶体特异性标记物结合异硫氰酸荧光素的花生凝集素检测了34例精液精子顶体结构的完整性。其中正常生育精液12例,弱精症精液12例,畸形弱精症精液10例。并且进一步检测了20例精液在体外诱导下精子发生顶体反应的能力,其中正常生育精液10例,不育精液10例。结果表明人精子顶体结构的完整性与精于正常形态百分率,存活率,前向运动百分率显著正相关(P<0.001)。不育组精子在体外诱导下发生顶体反应的能力明显低于生育组(P<0.01),说明流式细胞计能用于预测生育力。  相似文献   

16.
精子线粒体琥珀酸脱氢酶的检测及意义   总被引:6,自引:3,他引:3  
目的 :采用一种简便、快速的检测精子线粒体琥珀酸脱氢酶 (SDH)的改良方法检测精子SDH ,并评价其与精子活动率及存活率的关系。 方法 :4 6例年龄为 2 5~ 36岁 (平均 31岁 )生育与不育男性精液标本 ,采用计算机辅助精液分析系统检测精子活动率 ,应用改良SDH检测法检测精子SDH ,通过死、活精子荧光分子探针染色检测精子存活率 ,分析精子活动率、存活率及精子SDH阳性率之间的关系。 结果 :4 6例生育与不育男性精子活动率为( 6 7.33± 7.37) % ,存活率为 ( 79.78± 7.6 5 ) % ,精子SDH阳性率为 ( 74 .74± 8.2 9) % ;精子活动率、存活率及精子SDH阳性率 3者之间均存在显著相关性 (P均 <0 .0 1)。 结论 :精子线粒体SDH检测对评价精子线粒体功能具有重要意义 ,还可作为精子存活率的辅助指标  相似文献   

17.
Sperm chromatin integrity is vital for successful pregnancy and transmission of genetic material to the offspring. We evaluated chromatin integrity in sperm from 60 infertile men and 7 fertile donors comparing the sperm chromatin structure assay (SCSA), TdT-mediated-dUTP nick end labeling (TUNEL), the sperm chromatin dispersion (SCD) test, and acridine orange staining technique (AOT). The TUNEL and SCD assays showed a strong relationship with the SCSA (r > .866; P < .001) for sperm DNA fragmentation, both in infertile men and donors of known fertility. AOT did not show any relationship with SCSA. The breakdown of the DNA fragmentation index (DFI) into 3 categories (< or =15%, >15%-<30%, and > or =30%) showed that the SCSA, TUNEL, and SCD test predict the same levels of DNA fragmentation. AOT consistently showed higher levels of DNA fragmentation for each DFI category. DNA fragmentation in sperm between infertile men and donor sperm was significantly different (P < .05) under SCSA (22.0 +/- 1.6 vs 11.8 +/- 1.4), TUNEL (19.5 +/- 1.3 vs 11.1 +/- 0.9) and SCD (20.4 +/- 1.3 vs 10.8 +/- 1.1), respectively. DNA fragmentation in sperm evaluated by AOT did not differ (P > .05) between infertile men (31.3 +/- 2.4) and donors (32.7 +/- 4.8). AOT showed extreme variations for sperm DNA fragmentation in semen from both infertile men and donors. The problems of indistinct colors, rapid fading, and the heterogeneous staining were also faced. In conclusion, SCSA, TUNEL, and SCD show similar predictive values for DNA fragmentation, and AOT shows variable and increased levels of DNA fragmentation, which makes it of questionable value in clinical practice.  相似文献   

18.
Idiopathic oligozoospermia is one of the most important problems in Andrology, but up to now it is poorly understood because the often routine conventional semen parameters, unquestionably are not directly related to the evaluation of the morphological and functional integrity that determines the spermatozoan fertilizing capacity. A non complex strategy was designed to determine the presence of alterations in the functional integrity of the spermatozoa from infertile men with idiopathic oligozoospermia and from euspermic fertile men, by the quantitative analysis of the spermatozoan motility and the acrosome reaction. There was a lower percentage of acrosome reacted spermatozoa within the semen of the infertile men, accompanied with a significant decrease in the motility percentage, sperm velocity and motility index in comparison with semen from fertile men. These data strongly support a possible detrimental structural and functional integrity of the spermatozoa from the oligozoospermic men.  相似文献   

19.
We measured the seminal plasma levels of tissue factor (TF) and interleukin-6 (IL-6) in men and examined their relationship with sperm concentration and motility. The study comprised 71 patients in three groups: an infertile group with ( n=11) and without ( n=50) leukocytospermia and a fertile group ( n=10). The seminal plasma levels of TF were significantly higher in the infertile patients than in the fertile ones. The seminal plasma levels of both TF and IL-6 were significantly higher in the infertile patients with leukocytospermia than in those without leukocytospermia. In 54 nonazoopermic cases the seminal plasma levels of TF were significantly correlated with the sperm concentration and sperm motility. Further studies are necessary to clarify the role of TF in human fertilization.  相似文献   

20.
Summary. Complete semen analyses including computer-assisted sperm motility and morphology assessments were performed to determine if semen and sperm differed between HIV-seropositive men and fertile controls, or differed with symptoms, or CD4+ peripheral cell count categories. Previous studies included small numbers of men and presented conflicting conclusions. Two hundred and fifty non-vasectomized HIV-seropositive men and 38 fertile controls each provided one semen sample. Non-parametric statistics were used to analyse both continuous and nominal data. Fertile men had significantly greater semen volume, sperm concentration, percent motility, percent rapid and linear motility and total strictly normal spermatozoa than HIV seropositive men. Neither total number nor subtypes of leukocytes in semen differed between the two groups. Among the HIV seropositive men, significant differences in semen analyses were found between CD4+ cell count, clinical, and AIDS categories. Lower CD4+ cell counts (<200 mm−3) were associated with significantly lower percent motility, percent normal sperm morphology by strict criteria, significantly more spermatids in semen, and higher percentages of teratozoospermia, oligoasthenoteratozoospermia and leukocytospermia. Healthier men, based on clinical categories, had significantly more normal shaped spermatozoa and fewer had azoospermia, oligoasthenoteratozoospermia or leukocytospermia. Many HIV-seropositive men have normal semen analyses, but as the disease progresses more defects are found, particularly in strict criteria sperm morphology.  相似文献   

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