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1.
Reprod Biol Endocrinol ; 10: 115, 2012 Dec 24.
Artículo en Inglés | MEDLINE | ID: mdl-23265183

RESUMEN

BACKGROUND: Poor sperm quality can negatively affect embryonic development and IVF outcome. This study is aimed at investigating the influence of various lifestyle factors on semen quality according to MSOME (motile sperm organelle morphology examination) criteria. METHODS: 1683 male patients undergoing assisted reproductive technologies (ART) in our clinic were surveyed about their age, BMI (body mass index), ejaculation frequency, nutrition, sports, sleeping habits and social behavior. Semen samples were collected and evaluation of semen parameters according to MSOME and WHO criteria was performed. Results were grouped and statistically analyzed. RESULTS: Although single parameters had minor effects on sperm parameter, the combination of age, BMI, coffee intake, ejaculatory frequency and duration of sexual abstinence were identified as factors having a negative effect on sperm motility. Additionally, we could demonstrate that MSOME quality was reduced. The negative impact of age, BMI and coffee intake on sperm quality could be compensated if patients had a high ejaculation frequency and shorter periods of sexual abstinence. CONCLUSIONS: Combinations of adverse lifestyle factors could have a detrimental impact on sperm, not only in terms of motility and sperm count but also in terms of sperm head vacuolization. This negative impact was shown to be compensated by higher ejaculation frequency and a shorter period of sexual abstinence. The compensation is most likely due to a shorter storage time in the male gonads, thus reducing the duration of sperms' exposure to reactive oxygen species (ROS).


Asunto(s)
Estilo de Vida , Análisis de Semen , Motilidad Espermática , Espermatozoides/fisiología , Adulto , Factores de Edad , Índice de Masa Corporal , Café , Eyaculación , Ejercicio Físico , Femenino , Humanos , Masculino , Persona de Mediana Edad , Estado Nutricional , Estrés Oxidativo , Técnicas Reproductivas Asistidas , Abstinencia Sexual , Sueño , Conducta Social , Recuento de Espermatozoides , Cabeza del Espermatozoide/ultraestructura , Espermatozoides/ultraestructura , Factores de Tiempo , Vacuolas/ultraestructura
2.
Food Chem Toxicol ; 46(5): 1474-87, 2008 May.
Artículo en Inglés | MEDLINE | ID: mdl-18215450

RESUMEN

Ethanolic whole plant extract of Chelidonium majus, extensively used in traditional systems of medicine against various liver ailments, has been tested for its possible anti-tumor, hepato-protective and anti-genotoxic effects in p-dimethylaminoazobenzene (p-DAB) induced hepatocarcinogenesis in mice through multiple assays: cytogenetical, biochemical, histological and electron microscopical. Different sets of mice, 5 (for 7, 15 and 30 days' treatment) or 10 (for 60, 90 and 120 days) each, were chronically fed a diet suitably mixed with p-DAB and phenobarbital to develop liver tumors. One sub-group of carcinogen fed mice was also fed C. majus extract; 0.1 ml daily (drug-treated) while the other equal amount of dilute ethyl alcohol ("vehicle" of plant extract) (positive control). A separate group of mice was maintained with normal diet without any carcinogen treatment (negative control). Data of several cytogenetical endpoints and biochemical assay of some toxicity marker enzymes at all fixation intervals and histology of liver sections through ordinary, scanning and transmission electron microscopy at 60 and 120 days and that of spleen and kidney at 90 days were critically analyzed in the treated lots vis-a-vis controls. The results suggest anti-tumor, anti-genotoxic and hepato-protective effects of the plant extract, showing potentials for use in cancer therapy.


Asunto(s)
Anticarcinógenos/farmacología , Chelidonium/química , Neoplasias Hepáticas Experimentales/prevención & control , Alanina Transaminasa/sangre , Animales , Aspartato Aminotransferasas/sangre , Células de la Médula Ósea/efectos de los fármacos , Células de la Médula Ósea/ultraestructura , Carcinógenos/toxicidad , Aberraciones Cromosómicas/efectos de los fármacos , Peroxidación de Lípido/efectos de los fármacos , Masculino , Ratones , Pruebas de Micronúcleos , Microscopía Electrónica de Rastreo , Microscopía Electrónica de Transmisión , Índice Mitótico , Extractos Vegetales/uso terapéutico , Cabeza del Espermatozoide/efectos de los fármacos , Cabeza del Espermatozoide/ultraestructura , Fijación del Tejido , p-Dimetilaminoazobenceno/toxicidad
3.
Ecotoxicol Environ Saf ; 58(2): 194-201, 2004 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-15157573

RESUMEN

The genotoxic effects of cadmium chloride (CdCl(2)) and azadirachtin (Aza) were assessed singly and conjointly in a fish, Oreochromis mossambicus, with endpoints such as chromosome aberrations, abnormal red cell nuclei, abnormal sperm morphology, and protein content (both qualitative and quantitative) of selected tissues, namely, muscle, heart, eye, brain, gill, liver, spleen, and kidney. The primary objectives were, first, to examine if CdCl(2), a common pollutant, and Aza, a natural product of the neem plant used extensively as an 'ecofriendly' agent for many purposes, had any genotoxic effect of their own on nontarget aquatic organisms of economic importance; and second, if Aza could have any ameliorating effect on CdCl(2)-induced genotoxicity in O. mossambicus tissues. As compared with distilled water-treated controls, both CdCl(2) and Aza induced genotoxicity in O. mossambicus, the former in greater quantity than that produced by Aza. However, Cd-induced toxicity in O. mossambicus appeared to be ameliorated to some extent by Aza.


Asunto(s)
Cloruro de Cadmio/toxicidad , Aberraciones Cromosómicas/inducido químicamente , Insecticidas/toxicidad , Limoninas/toxicidad , Tilapia/genética , Animales , Azadirachta , Cloruro de Cadmio/antagonistas & inhibidores , Núcleo Celular/efectos de los fármacos , Combinación de Medicamentos , Electroforesis en Gel de Poliacrilamida , Eritrocitos/efectos de los fármacos , Eritrocitos/ultraestructura , Inyecciones Intramusculares , Cariotipificación , Masculino , Micronúcleos con Defecto Cromosómico/efectos de los fármacos , Pruebas de Mutagenicidad , Extractos Vegetales/toxicidad , Proteínas/análisis , Proteínas/química , Cabeza del Espermatozoide/efectos de los fármacos , Cabeza del Espermatozoide/ultraestructura , Tilapia/sangre , Distribución Tisular , Contaminantes Químicos del Agua/toxicidad
4.
Food Chem Toxicol ; 41(10): 1325-8, 2003 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-12909265

RESUMEN

The cytogenetic toxicity of the leaf extract of neem was evaluated in murine germ cells. The extract was found to induce structural and numerical changes in the spermatocyte chromosomes as well as synaptic disturbances in them at their first metaphase. A significant increase in the frequency of sperms with abnormal head morphology and the decrease in mean sperm count were also observed. This spermatotoxic effect of the neem extract corroborates its germ cell mutagenicity. The possible role of azadirachtin, the most active principle present in the neem extract, in producing the observed genotoxic effect is discussed.


Asunto(s)
Azadirachta/toxicidad , Carcinógenos/toxicidad , Mutágenos/toxicidad , Animales , División Celular/efectos de los fármacos , Cromosomas/efectos de los fármacos , Cromosomas/ultraestructura , Técnicas In Vitro , Masculino , Meiosis/efectos de los fármacos , Ratones , Extractos Vegetales/toxicidad , Hojas de la Planta/química , Recuento de Espermatozoides , Cabeza del Espermatozoide/efectos de los fármacos , Cabeza del Espermatozoide/ultraestructura , Espermatogonias/efectos de los fármacos
5.
Mol Reprod Dev ; 65(4): 446-53, 2003 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-12840818

RESUMEN

The low number of embryos produced from in vitro matured, fertilized, and cultured (IVM-IVF-IVC) oocytes of prepubertal goat is mainly due to a low incidence of sperm head decondensation at fertilization (Martino et al., 1995: Theriogenology 43:473-485; Mogas et al., 1997: Theriogenology 48:815-829). Thiol compounds stimulate glutathione (GSH) synthesis and improve the rates of male pronucleus (MPN) formation and embryo development. The present study was carried out to determine whether supplementation of the IVM medium with 100 microM of cysteamine, 100 microM of beta-mercaptoethanol, 0.57 mM of cysteine, and 0.57 mM cystine might improve the embryo development and intracellular GSH level of prepubertal goat oocytes. After 27 hr post IVM, a sample of oocytes was frozen and the intracytoplasmic GSH content was evaluated by spectrophotometry. IVM-oocytes were inseminated with fresh semen and cultured in SOF medium. Only the addition of cysteamine to IVM media significantly improved the percentage of the morula plus blastocyst yield compared to the control group (oocytes matured in absence of thiol compounds) (22.2 vs. 6.4%, respectively; P < 0.05). The percentage of expanded blastocysts in cysteamine and control groups was 13.0 and 2.6%, respectively, and the mean cell number per blastocyst was 86.8 and 60.5, respectively. None of the other thiol compounds studied significantly improved the percentage of embryos obtained. It has been demonstrated that prepubertal goat oocytes synthesize GSH during IVM and that thiol compounds increase this GSH synthesis. In conclusion, only the addition of 100 microM of cysteamine to the maturation medium improves embryo development from prepubertal goat oocytes although all the thiol compounds used in this study increased intracellular GSH content.


Asunto(s)
Cisteamina/farmacología , Desarrollo Embrionario y Fetal/efectos de los fármacos , Fertilización In Vitro/veterinaria , Glutatión/metabolismo , Cabras/embriología , Oocitos/fisiología , Animales , Blastocisto/fisiología , Cisteína/farmacología , Cistina/farmacología , Masculino , Mercaptoetanol/farmacología , Oocitos/efectos de los fármacos , Oocitos/metabolismo , Cabeza del Espermatozoide/fisiología , Cabeza del Espermatozoide/ultraestructura , Compuestos de Sulfhidrilo/farmacología
6.
J Basic Clin Physiol Pharmacol ; 13(4): 311-28, 2002.
Artículo en Inglés | MEDLINE | ID: mdl-12751899

RESUMEN

The present work was designed to study the effect of Azadirachta indica (Neem) powder on rat testis using the electron microscope. Male albino rats received 100 mg each A. indica leaf powder orally (by gavage). On alternate days, a second group of rats received 0.125 mg testosterone dipropionate intramuscularly. A third group received both A. indica leaf powder by gavage and testosterone dipropionate intramuscularly. Suitable controls were maintained. After autopsy, ultrastructural analysis of the testis revealed that animals treated with testosterone dipropionate showed well-developed Sertoli cells and germ cells with well-developed cytoplasmic organelles. By contrast, in A. indica-treated rats, intracellular spaces and vacuolization were observed in Sertoli cells; whereas in Leydig cells, cytoplasmic inclusions appeared diminished, and the configuration of granular endoplasmic reticulum appeared as a single unbranched tubule. In late spermatids, defects were observed in the mitochondrial sheath. The ultrastructural changes seen in the A. indica-treated group provide a clue that A. indica leaves might affect spermatogenesis through antispermatogenic and antiandrogenic properties.


Asunto(s)
Azadirachta/química , Testículo/ultraestructura , Animales , Núcleo Celular/efectos de los fármacos , Núcleo Celular/ultraestructura , Citoplasma/efectos de los fármacos , Citoplasma/ultraestructura , Células Intersticiales del Testículo/efectos de los fármacos , Células Intersticiales del Testículo/ultraestructura , Masculino , Tamaño de los Órganos/efectos de los fármacos , Extractos Vegetales/farmacología , Hojas de la Planta/química , Ratas , Ratas Wistar , Células de Sertoli/efectos de los fármacos , Células de Sertoli/ultraestructura , Cabeza del Espermatozoide/efectos de los fármacos , Cabeza del Espermatozoide/ultraestructura , Cola del Espermatozoide/efectos de los fármacos , Cola del Espermatozoide/ultraestructura , Espermátides/efectos de los fármacos , Espermátides/ultraestructura , Espermatogénesis/efectos de los fármacos , Testículo/efectos de los fármacos , Testosterona/farmacología , Fijación del Tejido , Vacuolas/efectos de los fármacos , Vacuolas/ultraestructura
7.
Reprod Nutr Dev ; 37(5): 481-92, 1997.
Artículo en Inglés | MEDLINE | ID: mdl-9436249

RESUMEN

The present study aims to ascertain whether dietary administration of a mixture of vitamins C and E may prevent the negative effects of paternal age on male fertility variables in the mouse. Experimental males were fed a standard diet supplemented with either a low or high dose of vitamins C and E. Oocytes enclosed in cumulus masses were inseminated using a 2 x 2 factorial design established according to whether males were young (3-4 months of age) or aged (22-24 months of age) and whether they were fed a control or antioxidant diet. Aged males showed a significant decrease in number of spermatozoa/mg epididymis when compared to young males. Dietary supplementation with low doses of vitamins C and E did not have any effect on sperm quality, fertilization and conceptus development in vitro. However, high doses of dietary vitamins C and E decreased the number of spermatozoa/mg epididymis, and increased the percentage of spermatozoa with misshapen heads distended in the distal part. These findings suggest that dietary supplementation with pharmacological doses of vitamins C and E may disturb spermatogenesis. The mechanism involved may be associated with either the antioxidant properties of vitamins C and E or their inhibitory action on steroidogenesis by Leydig and/or Sertoli cells.


Asunto(s)
Envejecimiento/fisiología , Antioxidantes/farmacología , Dieta , Cabeza del Espermatozoide/ultraestructura , Espermatogénesis/efectos de los fármacos , Espermatozoides/anomalías , Espermatozoides/fisiología , Animales , Antioxidantes/administración & dosificación , Ácido Ascórbico/administración & dosificación , Ácido Ascórbico/farmacología , Femenino , Fertilización In Vitro/efectos de los fármacos , Masculino , Ratones , Ratones Endogámicos C57BL , Ratones Endogámicos CBA , Espermatozoides/efectos de los fármacos , Vitamina E/administración & dosificación , Vitamina E/farmacología
8.
Hum Reprod ; 10(9): 2295-300, 1995 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-8530655

RESUMEN

The semen parameters and sperm ultrastructural morphology have been described in semen samples from two groups of Yemeni subjects. The first 'exposed' group comprised 65 khat addicts, while the second control group included 50 non-khat addict subjects. The mean age was 39.94 +/- 13.85 and 35.72 +/- 11.35 years in the exposed and control groups respectively, without a significant difference. The mean duration of khat addiction among the addicts was 25.34 +/- 12.96 years (range 6.00-48.00). Statistically significant differences were detected between the semen parameters of the two groups. Such parameters, including semen volume, sperm count, sperm motility, motility index and percentage of normal spermatozoa, were lower among addicts. Significant negative correlation was also found between the duration of khat consumption and all semen parameters (r ranged from -0.30 to -0.74). At the transmission electron microscopy level, a counting system was incorporated to compare the numbers of normal spermatozoa with deformed and dead spermatozoa in ultrathin plastic sections. The total mean percentage of deformed spermatozoa was approximately 65%. Different patterns of sperm deformation were demonstrated, and included both the head and flagella in complete spermatozoa, aflagellate heads, headless flagella and multiple heads and flagella. Deformed heads showed aberrated nuclei with immature nuclear chromatin and polymorphic intranuclear inclusions; these were associated with acrosomal defects. The deformed flagella demonstrated numeric aberrations of the axonemal 9 + 2 configuration and structural defects of their associated elements. Persistent cytoplasmic droplets were observed frequently. This study has shown for the first time the deleterious effects of khat addiction on semen parameters in general and sperm morphology in particular of all addicts, especially those who have consumed khat for longer periods of time.


Asunto(s)
Estimulantes del Sistema Nervioso Central , Infertilidad Masculina/inducido químicamente , Extractos Vegetales , Semen , Espermatozoides/ultraestructura , Trastornos Relacionados con Sustancias/complicaciones , Acrosoma/ultraestructura , Adulto , Axones/ultraestructura , Catha , Humanos , Infertilidad Masculina/patología , Infertilidad Masculina/fisiopatología , Masculino , Microtúbulos/ultraestructura , Persona de Mediana Edad , Mitocondrias/ultraestructura , Recuento de Espermatozoides , Cabeza del Espermatozoide/ultraestructura , Motilidad Espermática , Cola del Espermatozoide/ultraestructura , Espermatozoides/anomalías , Espermatozoides/fisiología , Yemen
9.
Exp Cell Res ; 219(2): 407-13, 1995 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-7641791

RESUMEN

In the mammalian sperm head the nucleus is tightly associated, in many species in its posterior part, with a large and dense nonfilamentous cytoskeletal structure, the calyx, whose major proteins are basic, representing a novel category of cytoskeletal element. Using specific antibodies, biochemical methods, and cDNA cloning we have characterized one of these calyx proteins, previously termed calicin, in bull and man. The polypeptide of 588 amino acids (Mr of 66,889; IEP 8.1) is very similar in the two species and is encoded by a approximately 2.2-kb mRNA that has been detected only in testis but not in any other tissue or cell culture examined. Sequence analysis has revealed that calicin is homologous to the kelch protein of the ring canal structure of Drosophila ovaries. In particular, it contains three consecutive repeating units of 48 amino acids each which are homologous to the so-called "beta-strand folds" occurring in proteins of the kelch family, including the actin cross-linking protein scruin of Limulus sperm and a series of other eukaryotic, bacterial, and viral proteins. Moreover, the amino terminal domain of calicin contains a region of about 100 amino acids homologous to an extended motif shared by the kelch protein as well as various zinc finger and poxvirus proteins. The possible role of calicin as a morphogenic cytoskeletal element in spermiogenic differentiation is discussed, also in relation to the demonstrated absence or altered arrangement of calicin in frequent forms of human teratozoospermia such as "round-headed" or other "postacrosomal sheath defect" sperm malformations.


Asunto(s)
Proteínas del Citoesqueleto/análisis , Cabeza del Espermatozoide/química , Secuencia de Aminoácidos , Animales , Secuencia de Bases , Bovinos , Clonación Molecular , ADN Complementario , Humanos , Masculino , Datos de Secuencia Molecular , Pliegue de Proteína , Homología de Secuencia de Aminoácido , Cabeza del Espermatozoide/ultraestructura
10.
Fertil Steril ; 57(3): 699-702, 1992 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-1740222

RESUMEN

Addiction is a major problem confronting the whole world today. Disruption of interpersonal relationships, economic loss, and crimes against property are frequent consequences. Harm to the individual himself extends to all physiological systems. In the present study, we examined semen samples of six addicts by light and electron microscopy. Oligoasthenospermia was demonstrated in five patients, and necrospermia was observed in one patient. Severe degenerative changes of the sperm heads were noted. Granular condensation of the chromatin with nuclear vacuoles was demonstrated. Persistent cytoplasmic droplets were frequently observed. Degenerated tails showing fragmentation of the plasma membranes and numerical aberrations of the 9 + 2 configuration were also present, together with thickened and disorganized fibrous sheaths. These results confirm the deleterious effects of addiction on the entire sperm structure.


Asunto(s)
Espermatozoides/ultraestructura , Trastornos Relacionados con Sustancias/fisiopatología , Adulto , Dependencia de Heroína/patología , Dependencia de Heroína/fisiopatología , Humanos , Masculino , Abuso de Marihuana/patología , Abuso de Marihuana/fisiopatología , Microscopía Electrónica , Trastornos Relacionados con Opioides/patología , Trastornos Relacionados con Opioides/fisiopatología , Opio , Cabeza del Espermatozoide/ultraestructura , Cola del Espermatozoide/ultraestructura , Espermatozoides/anomalías , Trastornos Relacionados con Sustancias/patología
11.
Acta Eur Fertil ; 18(3): 217-20, 1987.
Artículo en Inglés | MEDLINE | ID: mdl-3439410

RESUMEN

Effects of alcoholic seed extract of Abrus precatorius Linn. were investigated at a dose of 100 mg/Kg body wt./day/rat for 60 days on fertility, semen profile and sperm metabolism of orally administered sexually mature male albino rats using WHO protocols. Serum testosterone levels were also measured using RIA technique. The data revealed that the cauda epididymal sperm motility was significantly lowered with no effect in its sperm concentration by 60 days of feeding. The scanning electron microscopic study on sperm morphology exhibited decapitation, acrosomal damage and formation of bulges on midpiece region of sperms in treated rats. The biochemical studies on epididymal spermatozoa indicated alterations in their energy and/or oxidative metabolism as evidenced by a fall in succinate dehydrogenase and ATPase levels by extract allocation. It did not exert any effect in body and organ weights. But an average number of implantation sites in females after mating with the treated male rats markedly declined. Contrarily, a significant increase in serum testosterone levels was noted by 60 days of administration. Thus, the decrease in fertility rate in extract receiving animals is correlated with reduced sperm motility, metabolism and altered sperm morphology in epididymis.


Asunto(s)
Fertilidad/efectos de los fármacos , Lectinas/farmacología , Extractos Vegetales/farmacología , Animales , Masculino , Lectinas de Plantas , Ratas , Semillas , Recuento de Espermatozoides/efectos de los fármacos , Cabeza del Espermatozoide/efectos de los fármacos , Cabeza del Espermatozoide/ultraestructura , Motilidad Espermática/efectos de los fármacos , Testosterona/sangre
12.
Drug Chem Toxicol ; 6(4): 379-95, 1983.
Artículo en Inglés | MEDLINE | ID: mdl-6617532

RESUMEN

DEET (N,N-Diethyltoluamide) was applied dermally to groups of 80 Sprague Dawley rats 5 days/week for 9 weeks (63 days), at three dose levels, (100, 300, and 1000 mg/kg). The undiluted material was applied with micropipettes to shaved patches. There was no run off and the material wet out onto the skin. Dose levels were calculated based on mean weights and adjusted weekly by reweighing half the animals in each group and calculating a mean body weight. Animals were scheduled for kill at three times; days 36-37, 65-66 and 95-96 after initiation of treatment. Data collected at each kill included sperm count, viability as assessed by ATP levels and morphology; testes histopathology (control and high-dose groups only) and body and organ weights (liver, kidneys and testes). DEET, when applied dermally, did not alter sperm count, sperm morphology, sperm viability, body weight or food consumption at any dose level tested.


Asunto(s)
Benzamidas/farmacología , Supervivencia Celular/efectos de los fármacos , DEET/farmacología , Recuento de Espermatozoides/efectos de los fármacos , Espermatozoides/efectos de los fármacos , Adenosina Trifosfato/análisis , Administración Tópica , Animales , Peso Corporal/efectos de los fármacos , DEET/administración & dosificación , Ingestión de Alimentos/efectos de los fármacos , Masculino , Tamaño de los Órganos/efectos de los fármacos , Ratas , Ratas Endogámicas , Cabeza del Espermatozoide/ultraestructura , Testículo/efectos de los fármacos
13.
Mutat Res ; 74(5): 379-87, 1980 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-7207475

RESUMEN

The results of testing 54 compounds including 19 carcinogen/non-carcinogen pairs from a wide range of chemical classes are reported. Many carcinogens did not induce increases in abnormal sperm heads. In contrast compounds known to induce transmissible genetic damage in whole animals invariably induced dose-dependent large increases in the incidence of abnormal sperm heads. The test may be useful in assisting discrimination between compounds that only cause mutations in isolated cell systems from those which constitute a real genetic hazard for whole mammals.


Asunto(s)
Carcinógenos/farmacología , Evaluación Preclínica de Medicamentos/métodos , Mutágenos/farmacología , Cabeza del Espermatozoide/ultraestructura , Espermatozoides/ultraestructura , Animales , Relación Dosis-Respuesta a Droga , Masculino , Ratones , Pruebas de Mutagenicidad/métodos , Cabeza del Espermatozoide/efectos de los fármacos
14.
Arch Androl ; 3(1): 1-11, 1979.
Artículo en Inglés | MEDLINE | ID: mdl-485654

RESUMEN

Scanning electron microscopy (SEM) combined with x-ray analysis has been utilized to investigate the distribution of several elements within the head of human spermatozoon. Despite minor individual variations, a preferential localization of elements (Ca, K, S, P) has been found in the head portion of the cell that corresponds to the post-acrosomal cap and is involved in the fusion of gametes during fertilization.


Asunto(s)
Cabeza del Espermatozoide/análisis , Cabeza del Espermatozoide/ultraestructura , Espermatozoides/análisis , Espermatozoides/ultraestructura , Calcio/análisis , Microanálisis por Sonda Electrónica , Humanos , Masculino , Microscopía Electrónica de Rastreo , Fósforo/análisis , Potasio/análisis , Azufre/análisis
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