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排序方式: 共有775条查询结果,搜索用时 31 毫秒
721.
The present experiment was conducted to study the impact of portal-drained visceral (PDV) metabolism of arterial 3-OH-butyrate on estimates of the portal recovery of intraruminally infused butyrate. Three multicatheterized and rumen-fistulated Leicester ewes were subjected to three intraruminal infusion protocols in a Latin square design: control (C; water), butyrate (B; 20 mmol x h(-1)), and butyrate (20 mmol x h(-1)) + propionate (40 mmol x h(-1)) (BP). During the experiments, the sheep were infused with 1,2,3,4-13C4-D-3-OH-butyrate in a mesenteric vein. Portal recoveries of intraruminally infused butyrate and propionate were obtained by comparing Treatments B and BP, respectively, with Treatment C. The portal net appearance of butyrate and the portal net appearance of butyrate + 3-OH-butyrate accounted for 20 +/- 2% and 48 +/- 14% of intraruminally infused butyrate, respectively. Metabolism by the PDV tissues accounted for 32 to 44% of the whole-body irreversible loss rate of 3-OH-butyrate (12.0 to 24.7 +/- 0.5 mmol x h(-1)). The portal net appearance of butyrate plus the unidirectional PDV output of 3-OH-butyrate accounted for 62 +/- 5% of the intraruminally infused butyrate, and this estimate was comparable to the portal recovery of intraruminally infused propionate (62 +/- 7%). The results from the present study show that the extent of epithelial butyrate oxidation is overestimated and the portal recovery of butyrate carbon underestimated if only portal net appearance rates of butyrate and 3-OH-butyrate are considered. 相似文献
722.
K K Kristensen 《Nordisk veterinaermedicin》1974,26(3):188-196
723.
Virginia Buechner-Maxwell Michael A. Scott Leanne Godber Annemarie Kristensen 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》1997,11(5):304-308
Neonatal alloimmune thrombocytopenia is recognized as a spontaneous disease of human infants, piglets, and possibly mules, but it has not been previously reported in horses. A 1–day-old Quarter Horse foal presented to Michigan State University Large Animal Clinic with severe thrombocytopenia of unknown origin. Immunoglobulins that bound to the foal's platelets were identified in the mare's plasma, serum, and milk by indirect assays. The immunoglobulins were further shown to recognize platelets from the foal's full brother, born 1 year earlier. These findings, coupled with the clinical course of the foal during its period of hospitalization, strongly suggest that neonatal alloimmune thrombocytopenia can spontaneously occur in neonatal horses. This diagnosis should be considered for foals with severe thrombocytopenia when other causes can be excluded, and platelet antibody assays should be used to support this diagnosis. 相似文献
724.
725.
Immunofluorescence studies of canine distemper encephalitis on paraffin-embedded tissue. 总被引:1,自引:0,他引:1
A paraffin-embedding technique for fluorescent antibody studies of canine distemper encephalitis was developed. Specific fluorescence was demonstrated in all brain tissue from dogs with canine distemper, and when compared with tissue on cryostat sections, the paraffin-embedded tissue showed superior preservation of tissue architecture. The preservation of viral antigen was good, and the appearance of fluorescence in gray- and white-matter lesions was described. In gray matter, extensive fluorescence was found mainly in neurons; fluorescence in white matter was less extensive and was mainly associated with astrocytes. 相似文献
726.
727.
728.
Organic beef production from steers demands several decisions concerning grazing strategy, feeding level in the winter and aspects as slaughter weight and length of the finishing period. A model has been developed to optimise these strategies. The objective of this study was (1) to find optimal strategies for organic beef production from steers regarding grazing strategy, feeding level in winter, finishing and slaughter in organic beef production from steer concerning economic output per time unit using a multi-level hierarchic Markov process and (2) to analyse the stability of these results by sensitivity analysis. The results showed that in general the optimal strategy only changes slightly depending on the criterion (net returns per steer versus per time unit). An optimization per time unit in some cases favours a more intensive production based on high feeding level in winter and finishing of steers as well as earlier slaughtering compared to an optimization per steer. Finishing of steers seemed not to be an optimal strategy from an economic point of view and price changes in feed, beef and premiums did not favour finishing of steers. Beef prices as well as prices for ryegrass/white clover pasture and low feeding level seemed to be the most important factors that influence net return. 相似文献
729.
Thromboelastographic evaluation of hemostatic function in dogs with disseminated intravascular coagulation 总被引:2,自引:0,他引:2
Wiinberg B Jensen AL Johansson PI Rozanski E Tranholm M Kristensen AT 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》2008,22(2):357-365
BACKGROUND: There is considerable variation in the coagulation profile of dogs with disseminated intravascular coagulation (DIC), making it difficult to assess overall hemostatic function. OBJECTIVES: To characterize the overall hemostatic state in dogs with DIC, by use of tissue factor-activated thromboelastography (TF-TEG), and to determine whether there is an association between hemostasis and outcome. ANIMALS: 50 dogs with DIC. METHODS: Dogs admitted to the intensive care units, with an underlying disease known to predispose to DIC, were prospectively assessed with TF-TEG. Citrated blood samples were collected daily during hospitalization and an extended coagulation panel and TF-TEG were performed. Diagnosis of DIC was based on expert opinion. RESULTS: Hemostatic dysfunction was observed on the TF-TEG profile in 33/50 of the dogs, of which 22/50 were hypercoagulable and 11/50 were hypocoagulable based on the TF-TEG G value alone. There were significant differences in k, alpha, and MA values (P < .0001) among hypo-, normo-, and hypercoagulable dogs. There was a significant difference in case fatality rate between hypo- (64%) and hypercoagulable (32%) dogs (relative risk = 2.38; P= .04). Dogs that died had significantly lower antithrombin activity (P= .03) and higher d-dimer concentration (P= .03) than survivors. CONCLUSIONS: The most common overall hemostatic abnormality in dogs diagnosed with DIC was hypercoagulability, and there was significant difference in survival between hyper- and hypocoagulable dogs. The results suggest TF-TEG is valuable in the assessment of hemostatic function in dogs diagnosed with DIC. 相似文献
730.
Rauch A Krüger L Miyamoto A Bollwein H 《The Journal of reproduction and development》2008,54(6):447-453
The goals of the present study were to investigate whether colour Doppler sonography can be used to differentiate temporary from persistent ovarian follicles and follicles with luteal tissue from follicles without luteal tissue and to assess the response of follicular cysts to administration of a gonadotropin releasing hormone (GnRH) analogue. Fifty-four cows having ovarian follicular structures with a diameter of >15 mm but no corpus luteum were included. These cows were examined via B-mode and colour Doppler sonography. The same examinations were repeated 10 to 12 days later, and the cows with follicular cysts (n=17) received a GnRH analogue. Blood flow was measured before and 30 min after treatment. Ten to 12 days later, the response to treatment was assessed using B-mode sonography. While 31 of 54 follicles disappeared spontaneously (temporary follicles), 23 follicles persisted and were diagnosed as cystic ovarian follicles (COFs). There was no difference between temporary follicles and COFs in regard to total area, wall thickness or the perfused area. In the luteinized follicles (n=13), based on the plasma progesterone concentration, total area was twice as large, wall thickness was three times greater and the perfused area was 4.5 times larger than those of the non-luteinized follicles (n=41). The sensitivity of diagnosing luteinized follicles was 61.5% using B-mode sonography and 92.3% using colour Doppler sonography. Twelve cows responded to GnRH, and five cows did not. There was a trend (P=0.07) toward higher (59.3%) blood flow in the cyst wall 30 min after treatment in the responding cows compared with the non-responding cows. Our results showed that the perfused area more accurately reflects active luteal tissue than wall thickness. Thus, colour Doppler sonography is superior to B-mode sonography for differentiating follicular and luteal cysts and aids in the selection of treatment. However, exact prediction of COFs destined to regress or persist and the response of COFs to treatment with a GnRH analogue were not possible using colour Doppler sonography. 相似文献