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1.
BACKGROUND: Recently, intracytoplasmic sperm injection (ICSI) of testicular spermatozoa retrieved surgically from patients with non-mosaic Klinefelter's syndrome resulted in several deliveries. The aim of this study was to evaluate the outcome of ICSI using fresh and cryopreserved-thawed testicular spermatozoa in these patients. METHODS AND RESULTS: Following informed consent regarding the genetic risks of their potential offspring, mature testicular spermatozoa were found in five out of 12 (42%) patients who underwent testicular sperm extraction, and ICSI was performed while excess tissue was cryopreserved. The mean age of the patients was 28.7 +/- 3.6 (range 23-36 years). Their baseline FSH was elevated (mean 38.3 +/- 11.4; range 22-58 mIU/ml). All patients had small testicles of 2-4 ml in volume. The outcome of ICSI using fresh or cryopreserved-thawed testicular spermatozoa during five cycles in each group, was compared. No statistical significant difference was found in the two pronuclear fertilization rate (66 versus 58%), embryo cleavage rate (98 versus 90%) and embryo implantation rate (33.3 versus 21.4%) for fresh or cryopreserved sperm accordingly. The clinical outcome after using fresh testicular sperm included two singleton pregnancies (one delivered and one ongoing) and a triplet pregnancy resulting in a twin delivery (after reduction of an 47,XXY embryo). After using cryopreserved-thawed testicular spermatozoa, two pregnancies were obtained resulting in one delivery of twins and one early spontaneous abortion. CONCLUSIONS: Outcome of ICSI using cryopreserved-thawed testicular spermatozoa of patients with non-mosaic Klinefelter's syndrome is comparable with that following the use of fresh spermatozoa. The genetic implications for the future offspring should be explained to the patients.  相似文献   

2.
Klinefelter's syndrome in the male infertility clinic   总被引:11,自引:0,他引:11  
The clinical features of patients with Klinefelter's syndrome attending a male infertility clinic have been investigated in order to consider their assisted reproduction treatment options. Over 12 years, a total of 148 patients with sterility due to azoospermia had Klinefelter's syndrome. Eight patients were shown by fluorescence in-situ hybridization (FISH) on metaphase spreads to be mosaic (46,XY/47,XXY), and 140 patients showed only 47,XXY. Small testes were observed in 95% of patients and gynaecomastia was seen in 12.4%. Half of the patients showed hypergonadotrophic hypogonadism, while others showed normogonadism (usually hypergonadotrophic). Spermatozoa were observed in semen from one patient with mosaicism and one without. Three-colour FISH revealed hyperploidy in 2.7% and 2.3% of these spermatozoa respectively. Multiple-site testicular biopsies in five recent patients were performed and yielded a specimen with round and elongated spermatids in one patient with 47,XXY karyotype. This sample was cryopreserved for future intracytoplasmic sperm injection. At follow-up, 46% of couples had chosen artificial insemination with donor sperm, and none had chosen adoption. Two patients developed testicular tumours, one a mature teratoma and the other a Leydig cell tumour. Two patients required androgen replacement therapy.  相似文献   

3.
Klinefelter's syndrome is a major contributor to male infertility. Recent reports of births after ICSI with especially testicular spermatozoa from infertile men with this syndrome are promising. The birth of a healthy girl after ICSI treatment with ejaculated spermatozoa from a man with non-mosaic Klinefelter's syndrome is reported. The non-mosaic karyotype was confirmed by chromosome analysis of both peripheral blood leukocytes and fibroblasts from a skin biopsy. In conclusion, in a very few cases, men with apparently non-mosaic Klinefelter's syndrome have ejaculated spermatozoa that can result in a birth of a healthy child following ICSI.  相似文献   

4.
During puberty, normal somatic Sertoli cells undergo dramatic morphological changes due to the differentiation of immature pre-Sertoli cells in functionally active adult Sertoli cells. Sertoli cell maturation is accompanied with loss of their mitotic activity before onset of spermatogenesis and loss of pre-pubertal and occurrence of adult immunohistochemical Sertoli cell differentiation markers. Testes of infertile adult patients often exhibit numerous histological signs of testicular dysgenesis syndrome (TDS) such as microliths, Sertoli cell only (SCO) tubules, tubules containing carcinoma in situ and immature seminiferous tubules (Sertoli cell nodules). Sertoli cell tumours, however, are very rare neoplasms possibly due to the fact that the mechanism and temporal origin of neoplastic Sertoli cells underlying Sertoli cell tumourigenesis still remain unknown. To clarify the state of Sertoli cell differentiation in both immature seminiferous tubules of adult patients with TDS and Sertoli cell tumour, we compared the expression of the Sertoli cell differentiation markers vimentin, inhibin-α, anti-Muellerian-hormone, cytokeratin 18, M2A-antigen, androgen receptor and connexin43 with that of SCO tubules with hyperplasia. In addition, we demonstrated for the first time the existence of proliferating Sertoli cells by Ki67- and PCNA-immunostaining in Sertoli cell nodules of the adult human testis. Our data indicate that mitotically active Sertoli cells in Sertoli cell nodules will be arrested prior to puberty and, contrary to dogma, do not represent foetal or neonatal cells. Since all markers in Sertoli cell nodules revealed a staining pattern identical to that in neoplastic Sertoli cells, but different to that in Sertoli cells of SCO tubules with hyperplasia, it may be speculated that Sertoli cell tumours in adult men may originate from Sertoli cell nodules.  相似文献   

5.
The birth of 12 healthy infants to fathers with non-mosaic Klinefelter's syndrome has been reported so far. The spermatozoa for these pregnancies was obtained from frozen-thawed ejaculate in one pregnancy (twins) and from the testis in the remaining 10 infants. All of them had a normal karyotype. We describe a patient with non-mosaic Klinefelter's syndrome from whom a testicular biopsy was obtained and motile spermatozoa were collected. Of 16 oocytes that were injected, 14 fertilized and cleaved. Three embryos were transferred, resulting in a triplet pregnancy. Karyotype analysis from chorionic villous sampling revealed 46,XX, 46,XY and 46,XXY from the three fetuses. The affected 46,XXY fetus was reduced on the 14th gestational week. The pregnancy culminated with the birth of a healthy male and female, on the 36th gestational week, weighing 3600 and 2660 g respectively. This case report proves the presence of hyperploid spermatozoa in the seminiferous lumen, and strengthens the necessity of genetic diagnosis of the embryos or fetuses in such pregnancies to fathers with non-mosaic Klinefelter's syndrome.  相似文献   

6.
BACKGROUND: Germ cell elimination and sperm DNA fragmentationin men with primary testiculopathies involve apoptosis-relatedprocesses whose mechanisms are poorly understood. This studyexamines the participation of typical (caspase-dependent) andatypical (caspase-independent) pathways in these processes.METHODS: Caspase activity and DNA fragmentation were evaluatedin Sertoli and germ cells from 63 men with non-obstructive azoospermiaand with different histological diagnoses who were undergoingtesticular biopsy for an assisted reproduction attempt. In eightof these men, phosphatidylserine externalization was also examined.RESULTS: The percentage of Sertoli cells showing caspase activityand DNA fragmentation was low and uniform in all diagnoses.In germ cells that remained tightly associated with Sertolicells despite vigorous mechanical treatment, the incidence ofboth caspase activity and DNA fragmentation was high, particularlyin men with maturation arrest. In Sertoli cell-free germ cells,high incidence of DNA fragmentation contrasted with low incidenceof caspase activity and phosphatidylserine externalization.CONCLUSIONS: In men with primary testicular failure, apoptosisof Sertoli cells is insignificant. Some germ cells undergo caspase-dependentapoptosis, show phosphatidylserine externalization and are tightlyassociated with Sertoli cells. Other germ cells show caspase-independentDNA fragmentation, do not externalize phosphatidylserine andlack a tight association with Sertoli cells.  相似文献   

7.
The involvement of Sertoli cells in different spermatogenic impairments has been studied by an immunohistomorphometric technique using cytokeratin-18 (CK-18) as a marker for immature Sertoli cells. CK-18 is known to be expressed in Sertoli cells during prenatal and prepubertal differentiation and is normally lost at puberty. Forty-nine azoospermic men were included in the current study. Quantitative measurements on testicular biopsies revealed the highest CK-18 expression in the mixed atrophy biopsies (22 men), a lower expression in the Sertoli cell-only (SCO) biopsies (12 men), and minimal residual staining in the group considered as representing normal spermatogenesis (six obstructive azoospermia patients). The cytokeratin immunopositive-stained tubules were associated either with arrest in spermatogenesis or with SCO. Examination of sections from nine men with microdeletions in the AZF region of the Y chromosome revealed that these men were either negative for CK-18 expression or showed only weak residual staining. This may suggest that the spermatogenic defect in the AZF-deleted men originates in the germ cell and has no impact on Sertoli cell maturation. The cause that determined the spermatogenic defect in the other cases of male infertility with high CK-18 expression may have damaged both the Sertoli and the germ cells.  相似文献   

8.
The present study aims to evaluate the injection of testicular round spermatids from patients with complete failure of spermiogenesis compared with that of mature epididymal and testicular spermatozoa. Over a period of 8 months, 188 azoospermic patients were evaluated with a view to their inclusion in our intracytoplasmic sperm injection (ICSI) programme. All patients had had a previous testicular biopsy; 38 had pure obstructive azoospermia, while 150 had non-obstructive azoospermia. Mature spermatozoa were found in 93 patients, whereas spermatozoa were entirely absent, with a predominance of round spermatids in 87. In eight patients, spermatids could not be found and therefore their cycles were cancelled. There was an early appearance of the two pronuclei stage in the round spermatid group compared with the mature spermatozoa group of patients (10.2 and 16 h respectively). The fertilization rate was also significantly lower (P = 0.00001) in the round spermatid group. The numbers of embryos developed and of embryo transfers in the round spermatid injection group were significantly lower compared with the mature spermatozoa injection group (P = 0.05 and 0.0001 respectively). No pregnancies resulted from round spermatid injection, while 18 pregnancies were achieved from the injection of mature spermatozoa. In conclusion, injection of round spermatids from patients with complete failure of spermiogenesis resulted in a significantly lower fertilization rate and a higher developmental arrest compared with injection of mature spermatozoa. With no pregnancies achieved, one may question the unusual variability of reported success rates and stress the need for further research in order to improve the outcome of this novel technique.  相似文献   

9.
Klinefelter's syndrome is one of the known causes of azoospermia or cryptoazoospermia, and it may present in non-mosaic (47,XXY) or mosaic (47,XXY/46,XY) form. The likelihood of finding spermatozoa in the ejaculate or testicular tissue of patients with mosaic Klinefelter's syndrome is low, and with the non-mosaic form, even lower. We describe a patient with non-mosaic Klinefelter in whom initially non-motile spermatozoa were derived from searching the ejaculate. Ten mature oocytes were injected, but none was fertilized. Subsequently, testicular biopsy was undertaken in order to collect spermatozoa for oocyte injection. Fifteen motile sperm cells were found and injected. Nine oocytes were fertilized and cleaved; three embryos were transferred into the uterine cavity. The woman conceived and following a normal pregnancy delivered a healthy child. Genetic analysis of the neonate disclosed a normal 46,XY karyotype. Non-motile spermatozoa in the ejaculate did not prove their fertilization potential, but their presence did not exclude finding motile, fertile spermatozoa in the testicular tissue in a non-mosaic Klinefelter patient. This report is further evidence that normal spermatozoa with fertilization potential are produced in the testes of patients with Klinefelter's syndrome.  相似文献   

10.
The role of a telomerase assay in the recognition of Sertoli cell-only syndrome with testicular foci of haploid cells was evaluated. Men with Sertoli cell-only syndrome (n = 23) were given a new diagnostic testicular biopsy. Part of the biopsy was stained and the remainder was processed for the quantitative telomerase assay. After 3-13 months, a therapeutic testicular biopsy was performed. This material was minced and then examined using confocal laser scanning microscopy and fluorescent in-situ hybridization. Histology of diagnostic testicular biopsy material confirmed the diagnosis of Sertoli cell-only syndrome in all the participants. All seven men with a telomerase assay value in their diagnostic testicular biopsy of >42 total product generated (TPG) U/microg protein had haploid cells (i.e. spermatozoa and/or spermatids) in their therapeutic testicular biopsy. Among participants with telomerase assay values <42 TPG U/microg protein, only one man had haploid cells in his therapeutic testicular biopsy. Thus, telomerase assay values >42 TPG U/microg protein in the diagnostic biopsy identified 87.5% of the Sertoli cell-only syndrome men with haploid cells in their therapeutic testicular biopsy. Significantly higher values of the telomerase assay were found in men with testicular foci of haploid cells than in men without these foci. The use of a quantitative telomerase assay biopsy appears to be important for identifying those men with Sertoli cell-only syndrome who have foci of haploid cells and can be candidates for assisted reproduction techniques.  相似文献   

11.
In many species, including humans, chromatin remodelling during spermiogenesis is initiated with a marked increase in histone acetylation in elongating spermatids. We have investigated whether this process is disturbed when spermatogenesis is defective or in human testicular tumours. For this purpose, the presence of highly acetylated histone H4 was detected on testicular sections from men with a severe impairment of spermatogenesis of several origins, as well as in different types of testicular tumours. In most tubules devoid of germinal cells (including SCO, Sertoli cell only syndromes) or lacking spermatocytes and spermatids, the Sertoli cells' nuclei showed a global increase in histone H4 acetylation. A similar observation was made in the peritumoral seminiferous tubules of testicular tumour tissues, whenever they were lacking germinal cells, with carcinoma in situ (CIS) cells being hypoacetylated. The global hyperacetylation of elongating spermatids during spermatogenesis could be part of an intercellular signalling pathway involving Sertoli cells and germinal cells, which could be disturbed in cases of severe spermatogenesis impairment, as well as in tubes surrounding germ cells in testicular tumours.  相似文献   

12.
Klinefelter's syndrome and spinal cord injury are major causes of male infertility. Intracytoplasmic sperm injection (ICSI) is a relatively new method of assisted reproduction. A testicular biopsy was obtained from a patient with the double complications of non-mosaic 47,XXY Klinefelter's syndrome and spinal cord damage, and motile spermatozoa were collected. ICSI was then performed. Of the four sperm-injected oocytes, three became fertilized and cleaved. Two embryos were implanted, resulting in a single pregnancy with visible evidence of a heartbeat appearing at 6 weeks gestation. The pregnancy is now entering its 20th week. To the best of our knowledge, this is the first case of a pregnancy resulting from the sperm of a patient with double complications.  相似文献   

13.
BACKGROUND: Microdissection testicular sperm extraction (TESE) has provided new hope for successful sperm retrieval to patients with Sertoli cell-only syndrome (SCO). We determined expression of the inhibin alpha subunit, glial cell line-derived neurotrophic factor (GDNF) and stem cell factor (SCF) in Sertoli cells obtained from patients with SCO immunohistochemically and compared expression rates with rates of microdissection TESE sperm retrieval. METHODS: Testicular biopsy specimens were obtained from 52 men with non-obstructive azoospermia who underwent microdissection TESE and were diagnosed with SCO by histological analysis. RESULTS: All specimens showed intense staining for the inhibin alpha subunit. Moderate or intense staining for GDNF was observed in 65.8% of specimens. All but one showed moderate or intense staining for SCF. Among specimens negative for GDNF, the sperm retrieval rate was significantly higher (100%) for specimens with intense staining for SCF than for specimens with no or moderate staining (30.7%) (P<0.05) for SCF. CONCLUSION: GDNF expression differs among patients with SCO. The sperm retrieval rate was high in cases of no staining for GDNF and intense staining for SCF.  相似文献   

14.
BACKGROUND: Mutations of the androgen receptor (AR) gene give rise to a wide array of phenotypic abnormalities. A systematic analysis of the AR gene in patients with 47,XXY has not previously been performed. METHODS: Mutations of the AR gene and expansion of the CAG repeats in exon 1 of the AR gene were studied in 13 patients with Klinefelter's syndrome either with (n = 1) or without (n = 12) spermatogenesis. RESULTS: No abnormalities in the AR gene were detected by single strand conformational polymorphism analysis. The CAG lengths ranged from 17 to 27 (mean +/- SD 22.8 +/- 3.3, median 23) for Klinefelter patients or from 17 to 28 (mean +/- SD 23.2 +/- 2.6, median 23) for control subjects. X-inactivation analysis for the methylation status of the AR gene was performed in seven patients who were heterozygous for CAG repeats of different length, showing that the longer CAG repeat alleles underwent random but more frequent inactivation in five patients and skewed inactivation in two. CONCLUSIONS: An AR gene abnormality does not constitute an important factor for impaired spermatogenesis in patients with Klinefelter's syndrome.  相似文献   

15.
The effects of hypercholesterolaemia on testicular endocrine and exocrine function were evaluated. The influence of hypercholesterolaemia on sperm quality, quantity, and fertilizing potential was also determined. Ten mature rabbits (group A) were fed chow containing 3% cholesterol for 12 weeks. Ten control rabbits (group B) were fed normal chow for the same period. At the end of the experimental period testosterone profiles and sperm parameters were evaluated and the sperm reproductive potential was assessed by in vitro fertilization (IVF) techniques. Peripheral serum testosterone responses to testicular stimulation with human chorionic gonadotrophin, androgen-binding protein activity in testicular cytosols, sperm concentration, sperm motility, length of sperm midpiece, and IVF outcome were all significantly lower in group A than in group B. In contrast, serum cholesterol concentrations were significantly higher in group A. There were no significant differences in either testicular versus intra-abdominal temperature differences or cholesterol concentrations in seminal plasma or testicular tissue between groups A and B. The results suggest that hypercholesterolaemia has a detrimental effect on Leydig and Sertoli cell secretory function, spermatogenesis, epididymal sperm maturation process, and the overall sperm fertilizing capacity.  相似文献   

16.
This study was prompted by a hypothesis that testicular germ cell cancer may be aetiologically linked to other male reproductive abnormalities as a part of the so-called 'testicular dysgenesis syndrome' (TDS). To corroborate the hypothesis of a common association of germ cell cancer with testicular dysgenesis, microscopic dysgenetic features were quantified in contralateral testicular biopsies in patients with a testicular germ cell tumour. Two hundred and eighty consecutive contralateral testicular biopsies from Danish patients with testicular cancer diagnosed in 1998-2001 were evaluated retrospectively. Two hundred and eighteen specimens were subsequently included in this study, after 63 patients who did not meet inclusion criteria had to be excluded. The presence of carcinoma in situ (which is believed to originate from transformed gonocytes) was detected in 8.7% of biopsies. The incidence of other dysgenetic features was immature tubules with undifferentiated Sertoli cells, 4.6%; microcalcifications (microliths), 6.0%; and the presence of a Sertoli-cell-only pattern in at least a few tubules, 13.8%. The cumulative incidence of one or more signs of testicular dysgenesis was 25.2%. In a few patients, areas with immature and morphologically distorted tubules were also noted. Spermatogenesis was qualitatively normal in 51.4%, whereas 11.5% had very poor or absent spermatogenesis. It is concluded that microscopic testicular dysgenesis is a frequent feature in contralateral biopsies from patients presenting with testicular germ cell neoplasms of the adolescent and young type. The findings therefore support the hypothesis that this cancer is part of a testicular dysgenesis syndrome. The presence of contralateral carcinoma in situ was higher in the present study than previously reported.  相似文献   

17.
BACKGROUND. In vitro continuous stimulation of Sertoli cells with FSH leads to a desensitization of these cells to FSH action. To evaluate the presence of a desensitization of FSH receptor on Sertoli cells in vivo, we performed a controlled clinical study in 97 men affected by severe oligozoospermia. METHODS. On the basis of FSH and inhibin B plasma concentrations, these subjects were divided into three groups: group A, 33 subjects with high FSH and low inhibin B plasma levels; group B, 32 subjects with high FSH plasma levels and inhibin B concentrations at the lower limit of the normal range; and group C, 32 subjects with normal FSH and inhibin B plasma levels. Patients with high FSH plasma levels (groups A and B) were prospectively randomized into two subgroups, called A1, A2, B1 and B2. Patients of groups A1 and B1 were treated with a GnRH agonist, leuprolide acetate, to induce a hypogonadotrophic state and then were treated with recombinant human FSH (r-hFSH; 100 IU/day) and hCG (2000 IU/twice a week) for 2 months. Subjects of groups A2, B2 and C were treated only with r-hFSH for the same period. RESULTS. In patients of group A1, inhibin B remained unmodified during the whole period of study, whereas in subjects of group B1, we observed a significant reduction of this hormone during the hypogonadotrophic period and then an increase of inhibin B plasma levels that were higher that those observed before therapy. In patients of groups A2 and B2, FSH treatment did not induce a significant increase in inhibin B concentrations. In patients of group C, FSH induced a significant increase in inhibin B plasma levels. CONCLUSIONS. In infertile men, suppression of the high endogenous levels of plasma FSH associated with much lower exogenous FSH levels is able to evoke higher inhibin B production, which may indicate improved Sertoli cell function and the possibility that this could have a positive effect on spermatogenesis.  相似文献   

18.
Testicular germ cell cancer is aetiologically linked to genital malformations and male infertility and is most probably caused by a disruption of embryonic programming and gonadal development during fetal life. In some cases, germ cell neoplasia is associated with a relative reduction of Y chromosomal material (e.g. 45,X/46,XY) or other abnormalities of the Y chromosome. The euchromatic long arm of the human Y chromosome (Yq11) contains three azoospermia factors (AZFa, AZFb, AZFc) functionally important in human spermatogenesis. Microdeletions encompassing one of these three AZF loci result in the deletion of multiple genes normally expressed in testis tissue and are associated with spermatogenic failure. The aim of our study was to investigate whether AZF microdeletions, in addition to causing infertility, predispose also to germ cell neoplasia, since subjects with poor spermatogenesis have an increased risk of testicular cancer. We screened for putative deletions of AZF loci on the Y chromosome in DNA isolated from white blood cells of 160 Danish patients with testicular germ cell neoplasia. Interestingly, although AZF microdeletions are found frequently in patients with idiopathic infertility, in all cases studied of testicular germ cell cancer the Yq region was found to be intact. We conclude that the molecular aetiology of testicular germ cell neoplasia of the young adult type most likely does not involve the same pathways as male infertility caused by AZF deletions. Malignant transformation of germ cells is thus caused by the dysfunction of some other genes that still need to be identified.  相似文献   

19.
BACKGROUND: While (partial) recovery of spermatogenesis, observed by means of standard semen analysis, has been seen in testicular cancer patients after chemotherapy with cisplatin, sperm genomic integrity and its implication for the patient's fertility are poorly understood. METHODS: Semen and serum from 22 patients treated for testicular cancer were analysed pre- and post-chemotherapy. Besides routine semen analysis, sperm samples were evaluated by computerized karyometric image analysis (CKIA), chromomycin-A3 assay (CMA3, chromatin condensation) and TdT-mediated dUTP nick-end labelling assay (TUNEL, DNA damage). Serum FSH, LH and testosterone concentrations were measured. RESULTS: Ejaculate volume decreased post-chemotherapy (P<0.05). External sperm characteristics (CKIA morphometry) and sperm counts did not deteriorate after chemotherapy. An improvement in DNA condensation was assessed after chemotherapy (37 versus 50% and 47.5 versus 63.7% for CMA3 and CKIA respectively; both P<0.005); yet a high percentage of TUNEL-positive sperm was found in the samples (21 versus 25% for pre- and post-chemotherapy samples respectively). These values were significantly higher than those of a convenience sample of normozoospermic males attending pre-IVF screening. Serum FSH and LH (IU/l) increased after chemotherapy compared with pretreatment levels (8.1 versus 16.7 and 4.5 vs 6.8; both P<0.05, respectively). CONCLUSIONS: Despite the improvement in sperm chromatin packaging after chemotherapy, an abnormally high percentage of DNA-damaged sperm was found in these samples. As sperm quality does not reach normal levels after treatment, it remains difficult to outline the best strategy and guidance concerning fertility potential of testicular cancer patients.  相似文献   

20.
A comparison has been made between the morphological dimensionsof motile spermatozoa in subfertile men demonstrating a persistentexcess of non-sperm cells in their semen and those found inspematozoa from fertile controls. Scanning electron microscopyand image analysis were used to make a morphometric assessmentof defined sperm parameters in the study and control subjects.Half of the study cohort had an excess (>5 X 106/ml) of seminalleukocytes and the remainder an excess of sperm precursors inthe ejaculate. In subjects with a sperm precursor excess, themotile spermatozoa had several significantly larger head parametersthan those from both the fertile controls and those men witha leukocyte excess. Mid-piece and tail measurements did notdiffer significantly between groups. These findings suggestthat, where there are large numbers of immature germinal elementspresent in semen, there is aberrant morphological developmentof the motile, apparently mature, spermatozoa which may representdisordered spermatogenesis.  相似文献   

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