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1.
31 to 37 localities were examined in the small and large intestines of 48 calves spontaneously infected with cryptosporidiosis. It was found that cryptosporidia occurred the most frequently in the distal part of small intestine, within the range of six metres of small intestine, in front of the ostium ileocecale (OIC); at the ileocecal valve the incidence of cryptosporidia dropped rapidly. In none case were the protozoans revealed in duodenum and in the adjacent four to six metres of proximal jejunum. The small intestine was invaded by cryptosporidia in a variable manner, in some cases a major part was continuously invaded, in other cases only one or two metres of distal jejunum without any changes in the ileum and vice versa. Approximately half the calves had cryptosporidia in the cecum, fewer cryptosporidia were found in the transverse colon. Cryptosporidia in the rectum were found in about 25% of cases. Some calves had cryptosporidia only in the large intestine. The intensity of the mucous membrane invasion varied: mass incidence of cryptosporidia was found only in caudal parts of small intestine, with high variability of the extent and with sudden cases of negative findings. In the large intestine only the cecum was invaded more intensively and in a diffusive manner, in the transverse colon and in the rectum the groups of parasites were usually found at the openings and in the wall of Lieberk uhn 's crypts.  相似文献   

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This study was carried on the tongues of ten normal, healthy and adult fruit bats (Rousettus amplexicaudatus, also known as the nyap biasa bat) in Yogyakarta, Java Island, Indonesia. The tongue was protrusible, elongated and flat with a rounded apex, and its width and thickness increased gradually towards to lingual root. There were two main types of lingual papillae, mechanical (filiform) and gustatory (fungiform and circumvallate). The tongue was divided into three parts (apex, corpus and radix), and then, each part was subdivided into three regions (two lateral regions and a median region). There were six subtypes of the filiform papillae—three types on the anterior part (small, scale-like and giant), one type on the middle part (leaf-like papillae) and two types on the posterior part (rosette-shaped filiform and conical filiform papillae)—in addition to transitional papillae presented on the corpus and radix. Two types of gustatory papillae were represented by a small number of fungiform papillae that are scattered among the filiform papillae on the lingual apex and corpus, while three circumvallate papillae on the posterior part are arranged in a “V” shape pointing directly at the larynx.  相似文献   

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Uterine biopsies from normal cyclic cows were optimally prepared for examination in a scanning electron microscope. After examination in the scanning electron microscope the same tissues were routinely processed for paraffin sectioning and reexamined with the light microscope. Results indicate that the scanning electron microscope is satisfactory for examination of the fine surface structure of the endometrium and the light microscope for subsurface structures of the bovine uterus.  相似文献   

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Gastrointestinal segments from 4 healthy, 17-, 21-, 22- and 23-day-old calves fed on whole cow’s milk were examined. Scanning electron microscopy showed that the anterior duodenum had short villi varying in shape from leaf-shaped to nodular; the middle duodenum had broad, tongue-shaped villi and the anterior, middle, and parts of the posterior jejunum had slender, finger-shaped or leaf-shaped villi. The villi of the mucosa covering Peyer’s patches in the posterior jejunum were short and either conical or tongue-shaped; there were also small “pseudovilli” caused by bulges in the lymphoid tissue. Morphometry showed that the villi were longer in the anterior jejunum than in the duodenum and the posterior parts of the jejunum (P < 0.005). Morphologically fat absorption was most heavy in the anterior third of the small intestine. Moderate amounts of fat were also found in the epithelium of the posterior jejunum and of the abomasum. Large fat droplets were seen in apical duodenal enterocytes, in contrast to the small epithelial droplets in other areas with fat absorption. Nile blue staining indicated that the fat in the large droplets was esterified.  相似文献   

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In this study, we investigated the morphological identification of Toxocara canis and T. cati eggs on the basis of light and scanning electron microscopic (SEM) observations. T. canis and T. cati eggs used in this study were recovered from the uteri of respective gravid female worms. Measurement of egg size was not helpful in the differentiation of these species, because approximately 90% of eggs measured were of similar size. Using SEM, we were able to differentiate T. canis eggs from T. cati eggs based on their respective characteristic surface structures. Both species have subspherical eggs with markedly pitted surfaces like those of a golf ball, but the surface pitting in T. canis is more coarse than that in T. cati. In this study, however, these differences were not absolute, as 16% of T. canis and 29% of T. cati eggs showed surface pitting that was uncharacteristic of their species. Of the 16% of T. canis eggs that could not be differentiated by surface structure, 3% had pitting resembling T. cati, and the remaining 13% showed intermediate type surface pitting. Similarly, 5% of T. cati eggs resembled T. canis, and 25% of these were of intermediate type. Light microscopic observation yielded results similar to those of SEM, indicating that light microscopy is also a useful tool for the identification of Toxocara eggs.  相似文献   

11.
刘鹏  马利超  王宇  刘志鹏 《草业学报》2015,24(1):107-114
野豌豆属牧草适宜在高寒和高海拔地区栽培,是我国高原牧区重要的蛋白饲料来源。该属有190个物种,4个亚属:Vicia,Cracca,Ervum和Faba。本研究从中国、美国、土耳其和叙利亚等11个国家收集了16份野豌豆属牧草种质,利用扫描电镜对这16份材料的花粉形态进行观察。结果表明,野豌豆属植物花粉均以单粒形式存在,极面观为三裂圆形和三角形,赤道面观为扁圆形、长椭圆形和椭圆形。三沟萌发孔,沟长深入两端;极轴长为(9.60±1.52)(30.40±2.07) μm,赤道轴长为(11.80±0.84)(38.20±0.84) μm。花粉的表面纹饰呈3种类型:网状纹饰,脑状纹饰和疣状纹饰。网状纹饰根据外壁纹饰疏松程度不同,又可分为2种亚类型:粗网状纹饰和细网状纹饰。本研究较为系统地观察了16个野豌豆属牧草的花粉形态,探讨了其系统分类学特性,为揭示野豌豆属种质资源的遗传多样性奠定了基础。  相似文献   

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The aim of this investigation was to describe the normal ultrasonic appearance of the intestinal loops of calves at different stages of their adolescence and at various intervals after suckling and to determine reliable reference values. Therefore the abdomen of 20 clinically healthy calves have been examined with a 5 MHz sector probe on the right and left flank of each animal and the exact position, the largest diameter, the thickness of the walls, the peristaltic activity and the appearance of the contents of each part of the intestines described. Most often, the pars cranialis duodeni could be seen ventral of the right costal arch as well as in the right flank, with younger calves it also showed in the left flank sometimes. The position could be changed considerably depending on the period elapsed since the last suckling time.The duodenum descendens and the duodenum ascendens could be traced in the right flank. The thickness of the wall was found to measure between 2 and 3 mm throughout the whole duodenum. The examination of the jejunum and the ileum was basically done in the right flank. In cases where the rumen was not yet fully developed visualization was also possible in the left flank. Most often these parts were seen in cross-section displaying permanent peristaltic activity. With the younger calves the large intestine could equally be traced in both flanks. In older animals it could be recognized as voluminous hollow organ filled with gas, or in case of the colon ascendens as garlandshape. In the jejunum and ileum as well as in the large intestine the thickness of the wall measured between 1 and 2 mm. Each part of the intestine showed an increase in diameter as the calves grew older. The peristaltic activity increased during two hours after suckling and during this time the echoing level of the contents was lower.  相似文献   

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Feline monocytes and neutrophils functioned as effector cells in antibody-dependent cellular cytotoxicity (ADCC) against antibody-coated chicken erythrocytes. Using light microscopy, effector cell populations were identified in effector-target cell interactions, with further characterization of these identical individual effector cells by histochemical evaluations and scanning electron microscopy. Monocytes and neutrophils, but not lymphocytes, were observed attacking target cells. Carbonyl iron depletion of monocytes and neutrophils from peripheral blood leukocytes caused a marked reduction from a mean of 62% to 3.6% lysis in ADCC as measured by a 4-hour 51Cr release assay. Effector cells functioning in the ADCC reaction were visualized, using sequential analysis and light microscopy, histochemistry, and scanning electron microscopy.  相似文献   

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Immunosorption has become a very important biochemical and serological tool and it is the purpose of this paper to visualize this process qualitatively using the scanning electron microscope. Different carriers (i.e. CNBr activated cellulose and Sepharose, glutaraldehyde treated acrylamide-agarose beads Magnogel, and polystyrene cover slips) were coated with different antibodies and incubated with their homologous antigens such as pneumococci, ferritin, polymeric Salmonella flagellin and mechanically detached flagella, as well as tetanus toxoid, E. coli bacteriophage T4 and Rota virus particles. As negative controls the sorbents were incubated with heterologous antigens.  相似文献   

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Acanthogyrus (Acanthosentis) tilapiae parasites were collected from the intestines of 300 fish belonging to three tilapia species sourced at the River Nile, Giza, Egypt. The proboscis of the parasite was characterized by three rows of hooks that curved towards the posterior of the body. The first row is supported by unmodified hooks. The parasite tegument has a series of alternative folds and a large number of pores. Sensory ganglia are located on the surface of the proboscis and body. Acanthogyrus (Acanthosentis) tilapiae provokes an aggressive host response indicated by hyperplasia of the intestinal goblet cells and focal eosinophil infiltrations. This acanthocephalan parasite shows a highly modified adaptation to its site of host infection.  相似文献   

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A method is presented for locating individual leukocytes and platelets in Wright's stained blood films for comparative study by light and scanning electron microscopy. The individual cells in the blood films were photographed and the field was circled with a diamond marker objective. The slide was scored and broken; pieces of the stained slide containing the numbered circles were fixed (with conductive cement) to a metal stub, air dried, and coated with metallic gold. The metal stub was placed in a scanning electron microscope, and the marked cells were readily located and photographed so that their three-dimensional surface morphology could be compared with the morphologic features of stained cells in the blood film photographed with the light microscope. Characteristics of individual cell types are discussed.  相似文献   

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Scanning electron microscopy was used to examine canine tracheal cartilage and to determine the relationship between the fibrous and amorphous matrix in this tissue. Collapsed tracheal (CT) cartilage was hypocellular, compared with normal tracheal cartilage. The amorphous matrix of CT cartilage had a porous, fissured texture and did not have the homogeneous appearance of normal tracheal cartilage. Capillaries were seen to pass through CT cartilage. Randomly distributed connective tissue fibers, evident in CT cartilage matrix, were frequently attached to irregular shapes and sizes of amorphous matrix.  相似文献   

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This research aimed at revealing the structural features of Tibetan sheep's testicular and ovarian vasculature and providing theoretical basis for Tibetan sheep's physiological adaptability in plateau and low-oxygen environments. Through scanning electron microscopy, corrosion casts of the feature of the gonad arterioles were observed and analysed. The results of this study found that centrifugal arteries, centrifugal and centripetal arterioles were distributed in a ‘dendritic’ fashion in the testis lobule, the ovarian arteries and arterioles, which had a spiral shape. Testicular Tibetan Sheep knot-like artery had a denser spiral structure, and there were more branches in the microarteries. On the testis lobule and arteriole of caput epididymidis, the arteriole surface shows the ‘fusiform’ indentation to be more shallower. The ovarian artery had a higher degree of helix; its surface was distributed like a ‘bark-like’ indentation; and the ring was narrower and denser. Nevertheless, the arteriole network had a high concentration and a wide number of branches, as that of the ovarian arteriole network which had more end branches, the surface of the arterioles of ovaries and testicles was scarred and denser. The studies indicate that the structural features of testicular lobule, epididymal arterioles and ovarian arterioles are more conducive to increase the oxygen supply to the gonads tissue and controlling blood flow velocity and metabolism to respond to high altitudes and low-oxygen environments.  相似文献   

19.
The aim of this study was to cast a spotlight on the topography and to point out the clinical importance of the gastroesophageal junction (GEJ) in Anatolian Shepherd dogs. Nine Anatolian Shepherd dogs were used to study the morphology of the GEJ. The esophagus was appeared has a portion within the thoracic cavity while no portion of the esophagus presented within the abdominal cavity that documented the absence of the intra-abdominal portion in all studied dogs. The topographic anatomy, scanning electron and light microscopic examinations revealed that the gastroesophageal junction was located at the level of the phrenico-esophageal ligament (PEL) inside the esophageal hiatus. Our results were distinguished the morphology of the esophageal and gastric cardiac mucosa at the level of the gastroesophageal junction by the scanning electron micrographs. The light microscopical examination was explained the PEL attached to the esophageal side in one dog and to the gastric cardiac side in three dogs.  相似文献   

20.
Morphologic features of the canine atrioventricular (AV) node were evaluated, using histochemical cholinesterase reactions and scanning electron microscopy. Three distinct regions of the AV node were observed: the transitional zone, superficial AV node, and deep AV node. The transitional zone lacked distinct cellular arrangement, and the cells were large and round with extensive branching on the ends. Superficial AV nodal cells were elongated, tightly packed, and smaller than were transitional cells. The superficial AV node was the densest zone of the AV node. Cell-to-cell contact was end-to-end. Deep AV nodal cells were long, formed laminated fascicles, were larger than the superficial AV nodal cells, and were continuous with the AV bundle.  相似文献   

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