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941.
Samples of normal bovine palatine tonsils were examined by light and electron microscopy. Like human tonsils, they were composed of crypts, subepithelial areas, follicles, and T-dependent zones, but their well-developed capsule subdivided the lymphoid tissue by connective septa. B cells formed the major lymphoid component. The follicles and T-dependent zones had morphological and histochemical features typical of peripheral lymph organs. Follicular dendritic cells were isolated and shown to be similar to human follicular dendritic cells.  相似文献   
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Retrograde ejaculation was diagnosed in a 10-year-old Arabian stallion. Despite behavioral signs consistent with ejaculation, the collection receptacle of an artificial vagina remained devoid of semen on numerous occasions. Catheterization of the urinary bladder yielded large numbers of spermatozoa, even when an ejaculate was obtained, whereas low numbers (< 1 X 10(6)/ml) of spermatozoa are found in the bladder of clinically normal stallions after ejaculation. Endoscopic examination of the urethra, seminal colliculus, and bladder failed to reveal abnormalities. Medical treatment with imipramine hydrochloride apparently resulted in improvement initially, but was not curative. Further diagnostic and treatment measures were declined and the stallion was castrated. For stallions that seemingly fail to ejaculate or for ejaculates that contain lower seminal volumes or numbers of spermatozoa than expected, obtaining a urine sample after ejaculation via bladder catheterization is a simple diagnostic procedure that may be used to investigate the possibility of retrograde ejaculation.  相似文献   
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Twenty feline vaccine-associated sarcomas were examined by transmission electron microscopy. Tumors contained pleomorphic spindle cells, histiocytoid cells, and giant cells. Most tumors contained myofibroblasts, which had morphologic features similar to those of fibroblasts. These cells were further distinguished by subplasmalemmal dense plaques and thin cytoplasmic actin myofilaments organized as elongated bundles concentrated at irregular intervals forming characteristic dense bodies. Intracellular crystalline particulate material was found in 5 of the 20 tumors. Energy dispersive X-ray spectroscopy was used to identify the crystalline material within one tumor as aluminum-based. One tumor from a feline leukemia virus-infected cat contained budding and immature retroviral particles.  相似文献   
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An indirect sandwich enzyme-linked immunosorbent assay (ELISA) has been used for vesicular stomatitis virus (VSV) typing using sets of monovalent and polyvalent rabbit/guinea pig antisera for identification of VSV types New Jersey (VNJ) and Indiana (VIND). The VIND polyvalent antiserum (VIND-P) detects any strain of the 3 subtypes of the VIND type (VIND-1, VIND-2, and VIND-3) with the same strong reactivity. It is also possible to subtype the VIND strains using VIND-P rabbit antiserum as capture antibody and monovalent VIND-1, VIND-2, or VIND-3 guinea pig antisera as detector. The ELISA proposed has about 10 times more sensitivity and provides 10% more positive results than does the complement fixation 50% (CF50) test when epithelial samples are tested.  相似文献   
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