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1.
This study represents a continuation of part 1 of a study of the development of the bovine stomach. Material and methods are more fully described in part i of the study. In this part 2 of the study further developmental stages and morphometric analysis is presented.  相似文献   

2.
Retinal vascular patterns in domestic animals   总被引:8,自引:0,他引:8  
In this paper a morphological study of the retinal vascular patterns in various species of domestic animals is reported. A classification of these patterns into four well-defined groups is described. In the domestic ruminants, pigs and carnivores the retina contains a compact plexus of blood vessels located in the major part of the light-sensitive portion of the retina (euangiotic or holangiotic pattern). In other domestic animals blood vessels are present only in a smaller part of the retina. In the rabbit, vessels are confined to a broad horizontal band coincident with the area of dispersion of the myelinated nerve fibres. The larger of these vessels are readily visible macroscopically (merangiotic pattern). In the horse and the guinea pig the retinal blood vessels are minute and restricted to the direct neighbourhood of the optic disc (paurangiotic pattern). The avian retina is completely avascular (anangiotic pattern), but a densely vascularised pecten oculi is attached to the linear optic nerve head and protrudes far into the inferior part of the vitreous body.  相似文献   

3.
Transmissible Spongiform Encephalopathies are a group of chronic, always fatal diseases affecting the central nervous system of humans and animals. They occur in all species and are probably caused by agents called prions. In this minireview, a first part provides an overview of the various disease forms, a second part is devoted to the molecular biology of transmissible spongiform encephalopathies, and a last part deals with the specific problems of the Bovine Spongiform Encephalopathy.  相似文献   

4.
Clinicians are frequently presented with laboratory test results that are not consistent with preconceived expectations for a given case. One important reason for such results is the occurrence of preanalytical errors. In this article preanalytical errors are discussed in 2 parts. The first part covers the steps of sample collection, preparation, and transportation, in which preanalytical errors often occur. This part would be most useful if read in full before collecting a sample. The second part of this article includes a systematic review of preanalytical errors divided according to individual analytes or parameters or, when appropriate, groups of analytes and parameters that represent the same biological system. This part will hopefully serve the clinician as a quick and user friendly guide for identification of possible pitfalls when presented with unexpected laboratory test results for a given case. This article is limited to errors that can affect the complete blood count, chemistry, and coagulation panels.  相似文献   

5.
影响动物肠道锌吸收因素的研究进展   总被引:1,自引:0,他引:1  
锌可作为体内300多种酶的必需组分或激活因子而广泛参与体内的多种代谢活动。锌代谢的稳衡调节对于维持机体正常十分必要,其中,锌的吸收及其内源分泌是调节锌稳态的关键环节。本文综述了影响锌吸收的多种因素,并探讨了这些因素与锌吸收之间的关系,为畜牧业生产应用高效锌制剂提供参考。  相似文献   

6.
Distribution of cholinergic nerves in the oviduct wall in rabbits was investigated by a neurohistochemical method after El Badawi and Schenk (1967). Higher density of cholinergic nerve fibres was confirmed to occur mainly in the isthmic part, but in contrast with literary data it was also found in the ampullar part of oviducts. In the basal parts of oviduct mucosa there were only few cholinergic nerve fibres unlike their density in woman's oviduct. A major part of cholinergic nerves are concentrated in a thick muscular tissue; this is probable to be related with its influence on oviduct motility. In the course of pregnancy, progesterone reduces the number of cholinergic nerves in rabbit oviducts, the number is largely reduced in all layers. These results are considered as preliminary with respect to the number of test rabbits; they indicate that the rabbit oviduct is not any ideal model to study the development of cholinergic innervation in dependence on oestrous cycle phase and pregnancy duration and that they should not be applied to changes in the functional neuromorphology of tuba uterina in woman.  相似文献   

7.
In most mammals, the optic nerve fibers are myelinated in its extraocular part (EON) but not in its intraocular part (ION) and also in the retina. Transitional zone from the myelinated to unmyelinated optic nerve usually lies in the central part to the lamina cribrosa. It has been known that dogs contain exceptionally myelinated fibers in ION by light microscopy. The aim of this study was to investigate electron microscopically the retino-optic nerve junction in dogs and re-evaluate the barrier to migration of oligodendroblasts into ION. Fourteen adult dogs were used. EON was largely myelinated. In ION the percentage of myelinated fibers decreased gradually toward the retina. A narrow area of ION adjoining the retina was completely unmyelinated. In most mammalian optic nerves, oligodendrocytes are not found in ION. It has been suggested that oligodendroblasts are prevented from migrating from EON into ION; that is to say, there is a barrier to migration of oligodendroblasts. The lamina cribrosa, a dense meshwork of fibrous astrocytic processes, and a defect in the blood optic nerve barrier have been proposed as a candidate for the barrier to migration. Our results suggest, however, that these factors, at least in dogs, would be not involved in the formation of a barrier to migration of oligodendroblasts.  相似文献   

8.
在我国南方地区,西部天然牧地的营养价值与东部比较接近;生产力后者较高;生产量前者显著高.中高山地带天然牧地的营养价值高于丘陵低山地带,但生产力和生物生产量低于后者;营养生产量,西部以前者高,东部以后者高.与北方牧区比较,南方地区天然牧地的生产力较高,营养价值和生产量较低.从开发潜力看,南方地区西部高海拔地带以人工牧地较大;东部以农林用地生产饲用植物的较大.  相似文献   

9.
Nutritional support of the foal during intensive care   总被引:1,自引:0,他引:1  
Provision of adequate nutritional support to the sick neonatal foal is a vital part of intensive care; frequently, however, it is very difficult to accomplish. In this article, current recommendations concerning both enteral and parenteral nutrition are discussed.  相似文献   

10.
In a random selection of 50 adult dogs (25 males and 25 females) and 50 adult cats (25 males and 25 females), the incidence of ossification of the sesamoid structure of the popliteus muscle was characterized through anatomical dissection and radiographic techniques. The incidence of ossification was 84% in the dogs and 100% in the cats. In both anatomical and radiologic studies, it was demonstrated that when the knee was fully extended, the sesamoid bone was adjacent to the caudodistal part of the articular surface of the lateral tibial condyle in both dogs and cats. When the knee was flexed, the sesamoid bone articulated progressively with the more craniodorsal part of the tibial articular surface and when full flexion is obtained, it articulated with the articular part of the lateral surface of the lateral meniscus. The probable functions of the sesamoid bone are discussed.  相似文献   

11.
In spite of recent electromyographic experiments and myotomy on the pylorus, a detailed morphological study of that region is still lacking. In this study the pyloric part of the abomasum and the first 15 cm. of the duodenum have been investigated macro- and microscopically in 20 veal calves and 20 adult cattle. The circular muscle layer of the terminal part of the pars pylorica thickens into a proximal and a distal sphincter. Two U-shaped muscle loops, one on the visceral and the other on the parietal surface, are fixed by their base to the sphincter pylori. Together with longitudinal fibers of the abomasum and the duodenum, they may form a dilator pylori. A fibrous septum, which separates the muscular coat of the stomach from that of the duodenum is absent. Some longitudinal fibers of the abomasum are continuous with those of the duodenum. The loose mucosal folds in the pars pylorica and also the torus pyloricus may act as a mucosal plug in closing the pylorus. These findings are discussed in view of possible functional implications.  相似文献   

12.
13.
In the dog, the blood from the antebrachial part of the cephalic vein is typically drained by three vessels: the axillobrachial, the omobrachial and the proximal segment of the cephalic vein. In this work, two anatomical variations affecting the omobrachial and the proximal part of the cephalic vein in dogs are reported. The bilateral absence of the omobrachial vein was observed in two adult mongrel dogs and the lack of the proximal segment of the cephalic vein in one dog. These differences suggest that a certain degree of variation is normal in the layout of the superficial veins of the thoracic limb in the dog and implies that the blood egress from the cephalic vein in the dog, as in other species, is sometimes accomplished by only two veins.  相似文献   

14.
Since January 1st 1999 the use of antimicrobial growth promoters is forbidden in Switzerland. In a short review, the history of the utilisation of these substances, their effects in animal nutrition and the mode of action are described. The consequences of the prohibition are in part higher use of important antibiotics in prophylaxis and therapy.  相似文献   

15.
The structure of the adrenal gland was studied in 11 bottlenose dolphins ( Tursiops truncatus ), and five striped dolphins ( Stenella coeruleoalba ). These species are legally protected in Croatia. All examined animals died of natural causes and were found stranded along eastern Adriatic coast. In both species the adrenal gland consists of a cortex and a medulla; the cortex is divided into three zones. Whereas in the bottlenose dolphin, there is a zona arcuata which contains columnar cells arranged in the form of arches; in the striped dolphin this zone is replaced by zona glomerulosa containing rounded clusters of polygonal cells. In both species, the zona fasciculata consists of radially oriented cords of polygonal cells, whereas in zona reticularis cells are arranged in branching and anastomosing cords. The adrenal medulla in both species contains dark, epinephrine-secreting cells and light norepinephrine-secreting cells. Epinephrine-secreting cells are localized in the outer part of the medulla, whereas norepinephrine-secreting cells are found in the inner part, arranged in clusters and surrounded by septa of thin connective tissue. The gland is surrounded by a thick connective-tissue capsule, from where thick trabeculae extend towards the interior. In the bottlenose dolphin, group of cells resembling both medullar and cortical cells can be seen within the capsule; whereas only groups of cells resembling cortical cells are found within the capsule of the striped dolphin. In the bottlenose dolphin invagination of the adrenal cortex into the medulla is obvious as well as medullary protrusions extending through cortex to the connective tissue capsule.  相似文献   

16.
Lipomatosis of lymph nodes is defined as the replacement of the lymphatic parenchyma by adipose tissue which grows in the node from the hilus toward the cortical zone. In humans, it is considered as part of the normal aging process and is common in obese patients, but there are no reports in non-human primates. In this report, we describe the first case of lymph node lipomatosis in the bilateral axillary lymph nodes of a young adult cynomolgus monkey. Macroscopically, there were no apparent abnormalities in the axillary lymph nodes on either side, and their volumes were unchanged. At the cut surface, pale yellow fat-like tissue was observed in the medullary area. Histopathologically, well differentiated adipocytes replaced a large part of the lymphatic parenchyma in the area from the hilus to the medulla without any malignant findings. Based on these findings, the patient was diagnosed with lipomatosis of the lymph nodes.  相似文献   

17.
随着饲料行业竞争的加剧,饲料企业依靠品牌占领市场是必由之路。但很多中小型饲料企业在品牌建设的过程中存在一些认识上和操作上的误区,如品牌理念不成熟、品牌传播途径单一等。针对这些情况,本文提出了一些对策建议,如树立品牌战略意识、品牌推广中的整合传播、宣传和维护品牌等。  相似文献   

18.
Temporal skin plastic surgery, a possible method for eyelid reconstruction   总被引:2,自引:0,他引:2  
Eyelid reconstruction of large defects is a difficult undertaking in small animal surgery. Instead of performing the well known Roberts and Bistner or Cuttler and Beard methods, we have introduced the following method for eyelid correction in case of large lid defects. On the temporal part, laterally (about the width of the eye) from the eye an uneffected skin flap is identified, mobilized, rotated and placed into the missing part of the eyelid. Conjunctiva (with slow resorbing) and skin (with non resorbing) 1 metric material are separately adapted. In a large number of patients this method has been proven to be superior to the other methods mentioned.  相似文献   

19.
The tongue in the adult European mole (Talpa europea L.) was examined by scanning electron microscope. The elongated tongue with a rounded apex is about 12-13 mm in length and 3-4 mm in width. On the apex the shallow median groove is present. On the dorsal surface of the lingual mucosa two types of mechanical papillae and two types of gustatory papillae were observed. Mechanical papillae are represented by numerous filiform papillae with a single process, covering the whole surface of the apex and body of the tongue, and massive conical papillae, found on the root of the tongue. The structure and density of filiform papillae varies in the anterior and posterior part of the tongue. A unique trait of the tongue in the European mole is the occurrence on the apex of the tongue of a single row of conical papillae. Gustatory papillae are represented by numerous fungiform papillae and one pair of vallate papillae. Dome-shaped fungiform papillae in the anterior part of the tongue are arranged linearly along both margins of the tongue, whereas in the posterior part of the body of the tongue flat fungiform papillae are distributed evenly among filiform papillae. Oval vallate papillae are surrounded by a continuous furrow and a single pad. In the posterior part of the root behind conical papillae the surface of the mucosa is flat with numerous orifices of lingual papillae located there. Observations on the distribution and structure of gustatory papillae in the common mole did not show the existence of special traits, differing them from those in terrestrial insectivores. The comparison of the morphology of the tongue, the distribution and structure of the lingual papillae in the European mole with those in the other species of Insectivores, indicated of a general similarity of features within the family Talpidae.  相似文献   

20.
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