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The annular ligament constriction is characterized by a disproportion between the available space and the contents within the fetlock tunnel. The main symptoms are a persisting lameness, distention of the tendon sheath, a typical "notch" when the fetlock is viewed from the side and a hyperflexion pain in the fetlock. The surgical treatment consists of the transection of the fetlock annular ligament. The conservative management can be considered as a independent therapy or as a preparation for a subsequent desmotomy. The medical records of 75 horses suffering from fetlock tunnel syndrome presented at the Veterinary Surgery Clinic of the University of Zurich were studied. 39 horses with 41 affected limbs were reexamined clinically and ultrasonographically. 70% of the surgical cases and 82% of the conservatively treated cases were judged to be sound. Altogether it can be said that the surgical case group had a success rate of 62% while the conservatively treated group showed a success rate of 58%.  相似文献   
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Neutral glycosphingolipids (GSLs) are considered activation markers on human lymphocytes, which are fundamental for studying the immune system. For cattle, only a limited number of activation markers has yet been identified. We recently showed that Shiga toxin 1, known to use globotriaosylceramide (Gb(3) syn. CD77) as a cellular receptor, depresses proliferation of activated bovine lymphocytes [Infect. Immunol. 67 (1999b) 2209]. In order to confirm the expression of Gb(3)/CD77 on bovine lymphocytes, we flowcytometrically examined a bovine B-lymphoma cell line (BL-3) and bovine peripheral blood mononuclear cells (PBMC) before and after mitogenic stimulation and biochemically characterized neutral GSLs extracted from PBMC. CD77 was detected on the surface of BL-3 cells and cultured PBMC essentially after mitogenic stimulation. Although expressed by all PBMC subpopulations identified, the portion of CD7+ cells was highest for BoCD8+ cells, followed by B-cells and BoCD4+ cells at day 4 of cultivation. Ceramide trihexoside of stimulated PBMC was structurally determined as Gal(alpha1-4)Gal(1-4)Glc(1-1)ceramide (Gb(3)). Biochemically, Gb(3) was also detected within unstimulated PBMC which contained ceramide monohexoside (CMH) and Gb(3) in a ratio of about 4:1. However, stimulation induced an increase of CMH and Gb(3) by a factor of 2.5 and 10, respectively, implicating that bovine lymphocytes regulate surface expression of Gb(3)/CD77 predominantly by quantitative changes in the Gb(3) metabolism. This report presents Gb(3)/CD77 as the first GSL identified on bovine immune cells and highly recommends this activation dependent antigen as a useful tool to investigate lymphocyte activation within the bovine immune system.  相似文献   
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The study in Wistar rats attempted to improve the occlusion technique of the middle cerebral artery (MCA) as a precise method for initiating stroke. In a first part it was necessary to study the exact anatomy of blood vessels of the brain in seven rats of 170-410 g body weight by corrosion cast. The lengths and diameters of defined locations of the blood vessels were measured. The temporary as well as the permanent methods were refined or replaced. The first one was completed in main training the physiological blood flow after temporary occlusion, while the permanent occlusion was performed by positioning a silicone cap in the MCA. A filament guide was introduced from the common carotid artery (CCA) via internal carotid artery (ICA) to guide the silicon cap at the branch of the MCA. Histological sections of the brain of rats showed 24 h after the permanent occlusion a reproducible infarct in the brain. This area corresponded very well with the supply of the MCA. The new occlusion method with a silicon cap was compared with the occlusion methods of CCA route and external carotid artery (ECA) route. The total infarct volume was significantly larger in the CCA route and ECA route groups than in the silicon cap group (means: CCA route 261 mm3; ECA route 191 mm3 vs. 128 mm3 silicon cap group; P  < 0,05). It could be demonstrated that the new silicon cap occlusion technique imitates the pathological situation of a cerebral infarct in man. Moreover it is less invasive for the animals and more precise and reproducible regarding the infarcted area in comparison to the other occlusion methods. Based on anatomical measurements of the blood vessels the described silicon cap method can be recommended for rats of a body weight between 340–370 g.  相似文献   
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苏丹草种子生产及市场浅析   总被引:3,自引:0,他引:3  
张鸿书  马福 《草业科学》1997,14(3):37-39
对当前苏丹草种子生产,市场出现的问题,提出了解决途径和方法,以法制化制约市场,保护生产者,经营者和消费者的合法权益。  相似文献   
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Ohne Zusammenfassung  相似文献   
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This study reports on the purification of an antigen predominant within the vesicular fluid (VF) of T. crassiceps metacestodes and shown to share identity with the major vesicular fluid protein of the T. saginata larval stage. Purification was achieved by gel filtration of the VF on Sephacryl S-300 superfine, followed by ion exchange HPLC. The antigen represents a single polypeptide chain (Mr appr. 37,000) with carbohydrate moieties without affinity to ConA. Isoelectric focusing of the electrophoretical and immunological homogeneous antigen resulted in five bands focusing at pH 4.0, 4.2, 4.4, 4.6 and 4.8, respectively. In ELISA, the purified antigen detected serum IgG-antibodies in all 21-35 weeks old calves (n = 10) with experimental cysticercosis (70 to 6,000 viable larvae recovered). When compared to T. saginata metacestode VF the antigen was the better reagent for discriminating between infected and non-infected animals. As shown by immunodiffusion and ELISA the antigen is also common to the T. saginata adult stage and obviously to other taeniid metacestodes where it is accumulated in the VF or hydatid fluid.  相似文献   
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The rare case of a meningioma with pulmonary metastases in a dog is described. Clinically, the ten-year-old boxer bitch showed generalized seizures, strabismus and deficient proprioception. The post-mortem examination revealed a basically localized meningeal tumor, having the light- and electron-microscopic appearance of a malignant meningotheliomatous meningioma. Immunohistochemically, the tumor cells did not show any positive reaction with antibodies to GFAP, S-100 protein, NSE, vimentin, cytokeratin, desmin, and von Willebrand factor (factor VIII related antigen). Immunohistochemical examination of seven other canine meningiomas showed an identical pattern. The results and the relevant literature are discussed.  相似文献   
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