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As part of a series of studies designed to evaluate usual and potential functions of epithelial cells in the avian epididymis under varying circumstances, adult, sexually active male Japanese quails were vasectomised for 3, 6 and 8 weeks. The testes, epididymides and deferent ducts were studied histologically and ultrastructurally. Testicular lesions were minimal, but epididymal response was profound. Non-ciliated (type I) cells of the proximal efferent duct (PED) actively phagocytized spermatozoa and their fragments. An especially noteworthy and apparently novel observation was the proliferation of the lining epithelium in parts of the PED to form additional adluminal sheets of spermiophagic epithelium which did not lie directly on basal laminae. These sheets were composed exclusively of non-ciliated cells. Spermatozoal dissolution and macrophage activity were also important mechanisms for the disposal of superfluous and incarcerated spermatozoa in the epididymis of this bird.  相似文献   
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The response of the epithelial cells of the various ducts of the avian epididymis, whose function is poorly understood, to intraluminal bacteria was evaluated by the injection of an avirulent strain of Salmonella gallinarium into the RT for 24 h. Ultrastructurally, bacteria and invading mononuclear cells were present in the lumina of the RT, proximal efferent ducts (PED) and distal efferent ducts. However, only the non-ciliated (Type I) cells of the PED epithelium ingested bacteria from the lumen. Fragments of bacteria also occurred in several intercellular spaces in the epithelium of the PED. Some mononuclear cells also contained fragments of bacteria. Neither cell death in the various epithelia nor mononuclear infiltration of the periductal tissue occurred. Therefore, in addition to the established function of absorbing most of the testicular fluid entering the epididymis, the Type I cells also appear capable of recognising and removing foreign particulate matter from the epididymal through-flow in the proximal part of the epididymis.  相似文献   
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The macroscopic features of the arterial supply to the reproductive system of the male ostrich was studied in 16 pre-pubertal and eight sexually mature and active birds. The left and right cranial renal arteries arise from the aorta, between the cranial divisions of the kidneys. These vessels supply the cranial divisions of the kidneys, the testes, the epididymides and the cranial segments of the ducti deferentia. Accessory testicular arteries which arise directly from the aorta are present in 45.8% of the specimens. They supply the testes and cranial parts of the ducti deferentia. They are variable in number and origin, and four variants are identified. A cranial ureterodeferential branch originates from the cranial renal artery, supplies the cranial portion of the ductus deferens and ureter, and runs caudally to anastomose with the middle renal artery. The sciatic artery arises laterally from the aorta, just caudal to the acetabulum, and gives rise, ventrally, to a common trunk, the common renal artery, which divides into the middle and caudal renal arteries. The middle renal artery gives rise to the middle ureterodeferential branch which supplies the middle part of the ductus deferens and ureter. A few centimetres caudal to the kidney, the aorta terminates in three branches, namely, the left and right internal iliac arteries and the median caudal artery. The internal iliac artery divides into the lateral caudal artery and the pudendal artery; the latter gives off caudal ureterodeferential branches that supply the caudal segments of the ductus deferens and ureter. In addition, the pudendal artery gives off vessels that supply the cloaca, some of which continue to the base of the phallus, where they form an arterial network. In conclusion, the pattern of the blood supply to the reproductive organs of the male ostrich is, in general, similar to that of the domestic fowl and pigeon, although there are a few highlighted distinctive features.  相似文献   
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A microtubular mass (MM) defect was found in the spermatozoa of 7 Standardbred stallions; 3 stallions were sons of the same sire. Two of these 3 stallions and 2 other stallions (for a total of 4 out of the 7 stallions) were considered subfertile when the defect was first observed. Fertility improved with time, either during the first breeding season or when a given stallion was used less frequently; however, the MM defect persisted, consisting of tortuous arrays of small abnormal microtubules visible only by transmission electron microscopy. The MM probably contained the protein tubulin as indicated by immunofluorescence. Microtubules of the MM were different from normal microtubules in being highly coiled, rather than straight, without interconnecting bridges or arms and had a 20% smaller cross-sectional diameter than did normal microtubules. Synthesis of the MM may occur near areas of the nuclear membranes normally associated with the manchette of the developing spermatid.  相似文献   
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The various ducts of the epididymides of four gallinaceous birds, the turkey (Meleagris gallopavo), domestic fowl (Gallus gallus), guinea-fowl (Numida meleagris) and Japanese quail (Coturnix coturnix japonica) were studied at the scanning and transmission electron microscopy levels. The tissues were fixed either by immersion or vascular perfusion, for comparative purposes. Each duct system, save for a few details, presented similar morphological features in all species. The epithelial surface of the rete testis was regular and each cell bore a single cilium, as well as numerous, or in some parts, very few, short, regular microvilli. Each of the Types I and II non-ciliated cells of the proximal and efferent ducts displayed abundant, moderately long and regular microvilli, and a solitary cilium. The ciliated cells exhibited tufts of cilia. The Type III non-ciliated cell of the connecting and epididymal ducts exhibited a solitary cilium, and numerous microvilli which were intermediate in length between those of the rete testis and those of the efferent ducts. Vascular perfusion of the avian epididymal tissue was the superior method of fixation because it minimised the developments of fixation artefacts. Apocrine secretion did not appear to occur in the epididymis of these birds as the apical blebs of Types I, II and III cells, which have previously been reported, only manifest in this study in inadequately fixed tissues, and were therefore viewed as being artefacts. The present findings suggest that the current terminology, as applied to the avian epididymis, be retained.  相似文献   
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In a study of the absorptive activities of the excurrent ducts of the testis of birds, six adult cocks of the Ovambo breed of domestic fowl were deeply anaesthetised and intravascularly perfused with buffered 3 per cent glutaraldehyde. Epididymal tissue was prepared conventionally for electron microscopy. In favourable sections in three of these birds avid ingestion of spermatozoa was revealed in the non-ciliated (Type I) cells of the epithelial lining of the initial part of the proximal efferent duct, at and a little beyond its junction with the rete testis. No obvious defects were detected in luminal spermatozoa. The testicular excurrent ducts were neither distended nor obstructed, and mononuclear cell mobilisation was absent in both the ductal and periductal tissue. The significance of this observation with regard to the specific segment of the efferent duct system involved and how certain spermatozoa are identified for elimination from the duct lumen, must await precise studies.  相似文献   
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It remains a major concern that sperm structure has continued to be poorly investigated and reported in avian species. To our knowledge, sperm structure in the order Pelecaniforme has not been reported. Although McFarlane (1963; Proceedings of the XIII International Ornithological Congress; Ithaca, NY; American Ornithologists’ Union) reported the study of spermatozoa in two genera and two species of the family Ardeidae, he did not provide an account, or the names of the species examined. The present report on the sperm structure of the cattle egret, Bubulcus ibis, is, thus, the first in the order Pelecaniformes (this bird has been placed variably under the order Ciconiiformes, or the order Pelecaniformes). Five sexually mature and reproductively active male cattle egrets were obtained from the wild, humanely euthanized, the reproductive organs dissected out, and tissues from the ducti deferentia were prepared for transmission electron microscopy. The sperm structure of this bird is generally similar to that described for most non-passerine birds. However, the acrosome is a short, conical or bullet-shaped, blunt-ending organelle that lacks a perforatorium. The base of the acrosome is flat and makes contact with the nucleus along, a correspondingly flat plane. The nucleus, thus, ends anteriorly in a flat plane devoid of a concavity or a rostrum, and an endonuclear canal. The acrosomal and nuclear features of this bird are, therefore, main deviations from the situation in the non-passerine clade of birds.  相似文献   
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