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Polycythaemia vera was diagnosed in a three-year-old domestic shorthaired cat referred because of seizures and a high packed cell volume (PCV). Laboratory examination revealed severe erythrocytosis (PCV 79 per cent). Diagnosis was reached by excluding causes for relative and secondary absolute polycythaemia. As phlebotomy proved impossible for initial treatment due to hyperviscosity, four leeches were used to suck blood and the PCV was consequently reduced to 64 per cent. A further 24 hours later, when bleeding at the sites of sucking had stopped, the PCV was 56 per cent. Long-term management of the condition was achieved with hydroxyurea (100 mg/cat once daily) and intermittent phlebotomy. Initial treatment using leeches in cases of polycythaemia vera is a simple, non-invasive, well tolerated and effective method where phlebotomy is not possible.  相似文献   
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OBJECTIVE: To evaluate disposition of butorphanol after i.v. and i.m. administration, effects on physiologic variables, and analgesic efficacy after i.m. administration in llamas. DESIGN: Nonrandomized crossover study. ANIMALS: 6 healthy adult male llamas. PROCEDURE: Butorphanol (0.1 mg/kg [0.045 mg/lb] of body weight) was administered i.m. first and i.v. 1 month later. Blood samples were collected intermittently for 24 hours after administration. Plasma butorphanol versus time curves were subjected to pharmacokinetic analysis. Two months later, butorphanol (0.1 mg/kg) was administered i.m., and physiologic variables and analgesia were assessed. RESULTS: Extrapolated peak plasma concentrations after i.v. and i.m. administration were 94.8 +/- 53.1 and 34.3 +/- 11.6 ng/ml, respectively. Volume of distribution at steady state after i.v. administration was 0.822 +/- 0.329 L/kg per minute and systemic clearance was 0.050 +/- 0.014 L/kg per minute. Slope of the elimination phase was significantly different, and elimination half-life was significantly shorter after i.v. (15.9 +/- 9.1 minutes) versus i.m. (66.8 +/- 13.5 minutes) administration. Bioavailability was 110 +/- 49% after i.m. administration. Heart rate decreased and rectal temperature increased. Somatic analgesia was increased for various periods. Two llamas became transiently sedated, and 2 became transiently excited after butorphanol administration. CONCLUSIONS AND CLINICAL RELEVANCE: Although i.v. administration of butorphanol results in a short half-life that may limit its analgesic usefulness, the elimination half-life of butorphanol administered i.m. is likely to be clinically useful. The relationship among plasma butorphanol concentration, time, and analgesia differed with the somatic analgesia model; clinically useful analgesia may occur at lower plasma concentrations than those reported here.  相似文献   
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The intracellular dynamics of norsalsolinol, a neurotoxin candidate causing parkinsonism-like symptoms, in PC12 cells was studied. We found that dopamine and norsalsolinol are co-localized to secretory granule layer by sucrose density gradient in norsalsolinol-treated PC12 cells. The norsalsolinol was actively taken up into isolated secretory vesicle fraction from PC12 cells with a Km value of 41.5+/-6.8 microM. The uptake of 10 microM of norsalsolinol was sensitive to reserpine (1 microM), an inhibitor of vesicular dopamine transporter, and dopamine, an endogenous substrate, but insensitive to GBR-12909, an inhibitor of dopamine transporter on plasma membrane. In norsalsolinol-treated PC12 cells, exposure to high K+ or ATP resulted in simultaneous release of norsalsolinol and dopamine. Time course of a release of dopamine and that of norsalsolinol evoked by 50 mM KCl or 100 microM ATP corresponded to each other. These releases were dependent on the concentrations of secretagogues. These data suggest that norsalsolinol is taken up with dopamine into secretory vesicle via vesicular catecholamine transporter.  相似文献   
137.
The objective of the current study was to evaluate the effect of unrepresentative sampling of digesta particulate matter entering the omasal canal on the accuracy of fiber flow measurements. The experimental design comprised one period, one diet, and three cows as experimental units. Within each cow, the physical and chemical composition of digesta particulate matter was assessed at seven sites within the digestive tract. Three Finnish Ayshire dairy cows, equipped with ruminal and simple-T duodenal cannulas, in extended lactation were offered grass silage twice daily on an ad libitum basis. Digesta samples were collected from the rumen (dorsal and ventral sac), reticulum, omasal canal, omasum, duodenum, and rectum to determine particle size distribution in digesta, chemical composition of various particle size fractions, and distribution of two flow markers (Cr-labeled straw and indigestible NDF [INDF]) among particle size fractions. Digesta samples were wet-sieved using sieves of 2.50, 1.25, 0.630, 0.315, 0.160, and 0.080 mm. Particulate matter was analyzed for OM, NDF, and Cr concentrations, and INDF concentration was determined based on 12-d ruminal incubation. The particle size of digesta entering the omasal canal was larger compared with the omasum or the duodenum, suggesting that omasal canal samples were not representative of particle size distribution truly escaping the rumen. The concentration of potentially digestible NDF (PDNDF) decreased with decreasing particle size. The PDNDF concentration of particulate matter retained on all sieves was greatest in the rumen and gradually decreased along the digestive tract. From the reticulorumen to the omasum, the decrease was associated with decreased particle size, reflecting selective passage of particulate matter. In contrast, from the omasum to the duodenum and rectum, the PDNDF concentration decreased within each particle size fraction without effect on particle size, indicating a nonselective passage of particulate matter between these sites. Variation between particle size fractions was slightly greater for Cr concentration than for INDF concentration, indicating that unrepresentative sampling of particulate matter had a greater effect on Cr concentration compared with that of INDF. Owing to unrepresentative sampling, NDF entering the omasal canal was overestimated by 5% using INDF and underestimated by 7% using Cr as a particle phase marker. Of total NDF digestibility, proportionally 0.90, 0.07, and 0.03 occurred in the reticulorumen, omasum, and intestines, respectively. The current results indicate that, despite unrepresentative sampling of digesta particulate matter entering the omasal canal, the errors in determined NDF flow were small. The omasum may have a greater role in postruminal NDF digestion than the intestines.  相似文献   
138.
For the evaluation of hormonal control of spermiation in fish, a method to quanify the spermiation response of mature Rhynchocypris oxycephalus (Sauvage and Dabry) to hormonal therapy is described. Spermatocrit was determined after 7 min centrifugation at 18,000 ± g and sperm density was estimated by a standard hemocytomer method. Sperm density can be predicted from spermatocrit since their relationship is linear as described by the regression equation, Y = 3.68X - 27.18 ( R 2 = 0.82, N = 50). where Y is spermatocrit and × is sperm density. Milt production by mature R. oxycephalus was highest at 24 h after injection of 1,000 IU human chorionic gonadotropin (HCG) and 50 μg luteinizing hormone-releasing hormone analogue (LHRHa) per kg body weight. Increased milt production coincided with low spermatocrit and sperm density levels. These results demonstrate that spermiation in mature R. oxycephalus can be reliably evaluated by a spermatocrit method and that HCG and LHRHa are effective in stimulating of spermiation in this species.  相似文献   
139.
The stomach of the lesser mouse deer (Tragulus javanicus) was observed macroscopically. It consisted of only three compartments, rumen, reticulum and abomasum without omasum. The rumen was S-shaped with large ventral and caudoventral blind sacs and the reticulum was larger than the abomasum. Internally, the rumen was covered with numerous ruminal papillae even on the pillars and the ruminoreticular fold. These papillae were leaf- or tongue-like shaped and varied in size and density. The reticulum had honey-combed crests and the secondary crests were found rarely. The lips of the reticular groove were prominent and more developed in the aboral part than in the oral one. A sac-like transition zone, which had more prominent mucosal folds than had the floor of the reticular groove, was observed between the caudal end of the reticular groove and the abomasum. Mucosal folds of the abomasum were spiral, low but rather thick. These findings were discussed in view of comparison with other ruminants and of possible functional implications.  相似文献   
140.
Recent advances in uroendoscopy have allowed diagnostic evaluation of the lower urinary tract in most of our canine and feline patients. By providing a magnified view of the luminal surfaces of the lower urinary tract, uroendoscopy provides useful diagnostic information that is not readily available even by more invasive techniques.  相似文献   
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