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41.
The sperm duct epithelium of brook trout (Salvelinus fontinalis), mountedin vitro in Ussing-style epithelial chambers actively absorbs Na+ (measured as the short-circuit current, Isc) and secretes K+ (measured using86Rb+ as tracer). Dibutyryl-cyclic-adenosine monophosphate (db-cAMP) and 3-isobutyl-1-methylxanthine (IMX) produce a rapid, sustained stimulation of both ion transport processes, but the hormone connected to the response is unknown. Purified sockeye salmon CON A2 gonadotropin (GtH) produces a dose-dependent, rapid and sustained rise in Na+ uptake and K+ secretion. The time course, electrophysiological and transport characteristics are similar to those evoked by IMX. Carbohydrate-poor (chum salmon CON A1) GtH is ineffective. Pretreatment of fish with 17α,20β-dihydroxy-4-pregnen-3-one (17α,20β-P) significantly increases milt volume but is without effect on resting or stimulated (IMX + db-cAMP) levels of sperm duct ion transport. This is the first indication of a direct, rapid action of GtH on ion transport by the vertebrate blood-testis barrier. The results suggest direct involvement of GtH in control of later stages of sperm maturation.  相似文献   
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Clownfish, Amphiprion ocellaris Cuvier, produced and grown in an experimental indoor aquaculture facility, presented with lipomatous tumours. A total of 14 affected fish were examined. Based on the total number of fish at the aquaculture facility at the time of outbreak of this pathology, the scope of the incident is estimated to be 1 of 300 fish. The tumours were characterized by the presence of mature adipocytes of variable sizes, lipoblasts and by an invasive behaviour, which affected internal organs, muscle, central nervous system and, in one case, an eye. Detailed macroscopic and histopathological features are presented. The suggested diagnosis is that of a well‐differentiated liposarcoma, a diagnosis so far never applied to fish. The limited outbreak of the neoplasm lasted a few months in 2011 and did not recur. Possible factors leading to this phenomenon, notably the metastasis, are discussed.  相似文献   
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The records of 31 cats and eight dogs undergoing surgical correction of peritoneopericardial diaphragmatic hernia (PPDH) from 2000 through 2007 were reviewed. Weimaraners and long-haired cats of varying breeds, particularly Maine Coon cats, appear to be at higher risk of PPDH. Presenting complaints were most commonly related to the respiratory and gastrointestinal tracts in both dogs and cats, although respiratory signs were more prevalent in cats, and gastrointestinal signs were more common in dogs. The most common herniated organs were liver, gallbladder, and small intestine. Mortality associated with surgical repair of PPDH in cats and dogs was low in the first 2 weeks postoperatively, and prognosis for return to normal function was excellent. Peri-and postoperative complications were typically minor and self-limiting.  相似文献   
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A 6-yr-old maned wolf (Chrysocyon brachyurus) was diagnosed with an extraosseous osteosarcoma on the lateral aspect of the right thigh. Antemortem radiography revealed a calcified mass with no skeletal involvement. The mass was excised, but visible regrowth of the tumor was evident within 5 wk. Histologic examination and immunohistochemistry, including staining for p53 tumor suppression gene protein, were performed on the excised mass. The maned wolf was euthanized 13 wk after the initial diagnosis. The neoplasm was located in a site commonly used for the delivery of intramuscular injections, including vaccinations. Although no definitive association can be made, it is worth noting this relationship, as vaccine-site neoplasias have been observed in other species, most notably the domestic cat (Felis domesticus).  相似文献   
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Bronchial-associated immune development is critically important to protect neonates from respiratory infections. Herein, bronchial-associated immune development in formula-fed and sow-reared pigs is described. Colostrum-fed newborn piglets were fed medicated sow milk replacer formula beginning at 48 h of life or remained with the sow. Blood and tissues were sampled at one-week (d7) and three-weeks (d21) of age. Lymphocyte subpopulations, including T helper 2, cytotoxic T, memory T, and NK cells, in peripheral blood, mediastinal lymph nodes, and thoracic lymph nodes were identified using flow cytometry. Additionally, IL-1β, IL-6, IL-12, TNFα, TGF-β1, TGF-β2, IFNα, IFNβ, and dectin gene expression were analyzed by quantitative RT-PCR. Total IgG, IgM, and IgA concentrations in serum were analyzed. Dietary and developmental effects were observed. This set of baseline measurements provides a framework for future respiratory challenge studies where the effects of diet on the neonate's ability to resist and/or recover from infection can be tested.  相似文献   
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