نتایج جستجو برای: sperm head
تعداد نتایج: 203185 فیلتر نتایج به سال:
Eukaryotic flagella are responsible for the motile organelles that cause the migration of mammalian sperms. The lashing force and torque of the sperm flagellum contain critical information regarding the sperm health, as important evaluation factors for sperm screening. The objective of the study was to investigate the lashing force and torque of a sperm under physiological conditions using at...
Little is known about the genetic basis of evolutionary changes in sperm phenotype. Postcopulatory sexual selection is associated with differences in protamine gene sequences and promoters and is a powerful force acting on sperm form and function, although links between protamine evolution and sperm phenotype are scarce. Protamines are involved in sperm chromatin condensation, and protamine def...
Techniques for fertilizing golden hamster eggs in vitro have recently been developed (4, 14). Consequently, sperm entry into the egg can be followed with the phase-contrast microscope, and after semination eggs can be fixed at desired intervals for subsequent examination with the electron microscope. The probability of obtaining thin sections that demonstrate sperm penetration of an egg is enha...
Little detailed information is currently available on the incidence and morphological characteristics of abnormal sperm in the emu (Dromaius novaehollandiae) and of ratites in general. This situation is further compounded by the lack of a uniform system for the morphological classification of avian sperm defects. Considering the important role that sperm morphology plays in the assessment of se...
STUDY QUESTION Are urinary phthalate concentrations associated with altered semen quality parameters among males recruited from the general population? SUMMARY ANSWER Urinary levels of metabolites of phthalate diesters are associated with lower total sperm counts, larger sperm head sizes, and higher percentages of morphologically abnormal sperm. WHAT IS KNOWN ALREADY High dose experiments i...
During mammalian spermatogenesis, the diploid spermatogonia mature into haploid spermatozoa through a highly controlled process of mitosis, meiosis and post-meiotic morphological remodeling (spermiogenesis). Despite important progress made in this area, the molecular mechanisms underpinning this transformation are poorly understood. Our analysis of the expression and function of the putative se...
BACKGROUND Sperm proteins are important for the sperm cell function in fertilization. Some of them are involved in the binding of sperm to the egg. We characterized the acrosomal sperm protein detected by a monoclonal antibody (MoAb) (Hs-8) that was prepared in our laboratory by immunization of BALB/c mice with human ejaculated sperms and we tested the possible role of this protein in the bindi...
Sperm morphological analysis (SMA) is an essential step in diagnosing male infertility. Using images of human sperm cells, this research proposes a unique sequential deep-learning method to detect abnormalities semen samples. The proposed technique identifies and examines several components sperm. In order conduct study, we used the online Modified Human Morphology Analysis (MHSMA) dataset cont...
We have developed an assay for detecting the acrosome reaction in mouse sperm using chlortetracycline (CTC) as a fluorescent probe . Sperm known to be intact with nonreacted acrosomes show CTC fluorescence in the presence of Ca" over the anterior portion of the sperm head on the plasma membrane covering the acrosome . Sperm which have undergone the acrosome reaction do not show fluorescence on ...
OBJECTIVE To compare label-free interferometric phase microscopy (IPM) to label-free and label-based bright-field microscopy (BFM) in evaluating sperm cell morphology. This comparison helps in evaluating the potential of IPM for clinical sperm analysis without staining. DESIGN Comparison of imaging modalities. SETTING University laboratory. PATIENT(S) Sperm samples were obtained from heal...
نمودار تعداد نتایج جستجو در هر سال
با کلیک روی نمودار نتایج را به سال انتشار فیلتر کنید