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941.
Calcium fluxes were measured, in vivo, in both directions across the ovine reticulorumen wall of four sheep when the luminal potassium concentration was either 30 mmol litre-1 or 90 mmol litre-1. Neither fluxes were affected by an increased potassium concentration although net magnesium absorption was decreased (PO less than 0.05) and the transmural potential difference was increased (P less than 0.01) under these conditions. The results obtained suggest that, unlike magnesium, calcium is transported bidirectionally across ovine ruminal tissue independently of the transmural potential difference across the rumen wall.  相似文献   
942.
943.
944.
Epidural nerve block with 0.75% bupivacaine (1 ml/4 kg of body weight) was performed in 17 goats tranquilized by IM administration of acetylpromazine (0.07 mg/kg). For comparison, epidural nerve block with 2% lidocaine containing 1:100,000 epinephrine (1 ml/5 kg) was performed in 7 goats. Transient signs of CNS stimulation were observed during injection of bupivacaine in 5 goats and of lidocaine in 2 goats. Analgesia of the flank was inadequate for laparotomy in 4 goats given bupivacaine (including 1 goat given a two-thirds dose) and in 2 goats given lidocaine. Analgesia for these goats was provided by local infiltration of the operative site with lidocaine. With bupivacaine, the onset of analgesia was up to 40 minutes, and the duration of analgesia was several hours; most goats were unable to stand for at least 11 hours. In comparison, epidural nerve block with lidocaine had a more rapid onset and much shorter duration. For both anesthetic drugs, despite adequate analgesia for laparotomy, response to manipulation of abdominal viscera was observed in 12 goats. Arterial blood pressure and blood gas tensions were measured in 8 goats given bupivacaine; 3 goats had mean arterial blood pressure less than 70 mm of Hg. Seven goats had normal PaCO2 but 2 goats had low PaO2; 1 goat sedated with xylazine had increased PaCO2 and hypoxemia.  相似文献   
945.
Generally obese and lean pigs in both the fed and fasted states were anesthetized and then acutely infused with increasing concentrations of the beta-adrenergic agonist isoproterenol. Plasma free fatty acid (FFA), blood glycerol, glucose and lactate, and heart rate were monitored during the infusion period. Data were reduced by estimating the parameters of the generalized logistic function (minimum, maximum, ED50 and slope) and subsequently analyzed to compare the lean and obese genotypes within nutritional state. Lactate data could not be fitted to this function because the upper asymptote was not approached during the experiment. The minimum plasma concentration of FFA tended (P less than .1) to be less in obese than in lean pigs. The maximum, ED50 and slope for the responses of FFA were similar for obese and lean pigs in fed pigs and in fasted pigs. In fed pigs, the minimum glycerol concentration was greater in obese than in lean pigs, and the ED50 for heart rate tended to be lower in lean than in obese pigs. All other estimated parameters for the variables were similar in fed obese and lean pigs. In fasted pigs, the maximum glucose concentration was greater in obese than in lean pigs. All other parameters for the variables were similar in fasted obese and lean pigs. The results suggest that there was no major defect in lipid mobilization in these obese pigs (only a lower minimum FFA concentration was detected) and that an increased maximum blood glucose concentration in the fasting state might contribute to the obesity.  相似文献   
946.
The state of mucus synthesis in the goblet cells of the small intestine was studied in conventional piglets infected with a dose of 200,000 oocytes of the coccidium Isospora suis the first and fifth day after parturition. The synthesis of mucus and its chemical characteristics undergo significant changes during the third and fourth day after infection. The activity of acid and neutral mucous substances declines; their level and the physiological synthetic function of goblet cells begin to return to the normal during the period starting on the eight to tenth day after infection. However, there were no fully functioning goblet cells in the broken numerical ratio even at the end of the period of investigation, i.e. the 13th day after infection. The thin surface layer of mucus remained almost unchanged within the whole extent of the small intestine parts studied.  相似文献   
947.
Toxicity of Haemophilus pleuropneumoniae to porcine lung macrophages   总被引:10,自引:0,他引:10  
Viable Haemophilus pleuropneumoniae bacteria were toxic for porcine alveolar macrophages in vitro. This cytotoxic effect proved to be dose-related. A cell-free extract of H. pleuropneumoniae, heat-killed bacteria, and a Pasteurella multocida field strain were nontoxic. When macrophages were cultured with H. pleuropneumoniae bacteria in a ratio of 100 macrophages to six bacteria, ultrastructural signs of cellular degeneration were observed within 1 h. This degeneration was observed in macrophages with or without phagosomes containing H. pleuropneumoniae. A cytotoxic substance was filtered from a H. pleuropneumoniae culture in Eagle's minimal essential medium supplemented with Earle's salts (EMEM) and 10% foetal calf serum that was incubated for 10 h at 37 degrees C. This substance was destroyed by heating at 65 degrees C for 30 min. Macrophages were less susceptible to the toxic effect of H. pleuropneumoniae when serum of convalescent pigs was added.  相似文献   
948.
949.
A 3‐year‐old Burmese cat was presented with a history of nonresolving crusted and papular lesions of the face and prior treatment with prednisolone. Skin biopsies revealed typical pox lesions with hyperplasia and ulceration of the epidermis and eosinophilic cytoplasmic inclusion bodies in the epidermal cells. In the upper dermis there was prominent diffuse mast cell infiltration and mild neutrophilic and eosinophilic inflammation. Rare cytoplasmic inclusion bodies were also present in swollen endothelial cells of dermal venules, which showed no other degenerative changes. Histological diagnosis was confirmed by electron microscopic evidence of pox virus particles in inclusion bodies of epidermal cells. The lesions resolved within 6 weeks with systemic antibiotic therapy and supportive care. A 2‐year‐old domestic short‐haired cat was presented with multiple disseminated papular and ulcerative pox lesions with central eschar over the entire body. Histologically, large epidermal inclusion bodies (up to 6 μm in diameter) were present. Widespread haemorrhage and vascular wall necrosis was visible in the dermis and subcutis. Some subcutaneous vessels showed neutrophilic vasculitis. In addition to diffuse dermal neutrophilic and eosinophilic inflammation, a lymphohistiocytic panniculitis was also present. The cat died as a result of massive haemorrhage and lymphedema, despite supportive care. Funding: Self‐funded.  相似文献   
950.
This article presents important clinical pharmacologic aspects of drug therapy during pregnancy. It reviews the potential adverse effects on the mother and conceptus caused by drugs and includes specific recommendations for therapy. Extensive tables are included that list drugs that are safe and those that are contraindicated during pregnancy.  相似文献   
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