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Intravascular pulmonary artery sarcomas in combination with myocardial metastasis are rare in dogs. We describe the radiographic, echocardiographic, and electrocardiographic‐gated (ECG‐gated) computed tomographic angiography (CTA) findings in a dog with pulmonary artery sarcoma. All imaging studies demonstrated severe main pulmonary artery enlargement. Echocardiography and ECG‐gated CTA revealed a mass occluding the lumen of the right pulmonary artery. In addition, CTA revealed focal left ventricular myocardial contrast enhancement and parenchymal lung changes. Postmortem examination confirmed the presence of a large thrombus associated with arteriosclerosis and an intravascular sarcoma in the right pulmonary artery with metastases to the myocardium, lungs and brain.  相似文献   
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<正>近期伊利诺伊大学的J.A.Almeida博士、 Hans H.Stein博士以及Carsten Pedersen博士联手展开体重对于标准化回肠蛋白质和氨基酸吸收率的影响试验,结论证明,20 kg以下的仔猪回肠对于粗蛋白和氨基酸的吸收率比20~50 kg的育成猪和50~110 kg的育肥猪低。而且同一猪群的不同猪只也表现出吸收率的差异性。例如,在测定的300只仔猪中粗蛋白和氨基酸的吸收率  相似文献   
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An experiment was conducted to investigate the effects of BW, feed intake, and the physiological condition of the animal on the loss and amino acid composition of endogenous protein in swine. Ten growing barrows and five multiparous sows were equipped with a T-cannula in the distal ileum for digesta collection. A protein-free diet was fed to all animals. The barrows were given free access to the experimental diet. The sows also were allowed to consume the diet on an ad libitum basis, and digesta were collected during lactation and in the following gestation period. In addition, digesta from the gravid sows were collected after restricting the sows to 2 kg of feed per day. For each animal group, the endogenous losses of protein and amino acids were calculated in relation to DMI, and the amino acid composition of endogenous protein was calculated. The total endogenous gut protein loss at the distal ileum of growing pigs, lactating sows, and gestating sows, given free access to feed, was 12.4, 9.4, and 11.2 g/kg DMI, respectively. These values were not different (P > .10). However, when gestating sows were fed only 2 kg/d, 17.8 g of endogenous protein was lost per kilogram of DMI, which was higher (P < .05) than for any of the other groups. This difference was mainly caused by higher (P < .05) losses of glycine, proline, and serine. There were no differences (P > .05) in amino acid composition of endogenous protein between growing pigs, lactating sows, and gestating sows given free access to feed, but restricted-fed gestating sows had an amino acid composition of endogenous protein that was significantly different from that of the other groups. The results from the experiment showed that age, BW, and the physiological condition of the animal have little or no effect on the amount of endogenous protein and amino acids lost at the distal ileum of hogs if calculated in relation to DMI. Likewise, the amino acid composition was not affected by the BW or physiological condition of the animal. However, DMI had a significant effect on endogenous protein losses in sows as well as on amino acid composition of endogenous protein.  相似文献   
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In the pathogenesis of epilepsy aberrant synaptic plasticity plays an important role. Matrix metalloproteinases (MMPs) and their inhibitors (TIMPs) are responsible for nervous tissue remodelling resulting in synaptic plasticity in the central nervous system (CNS) and might therefore be crucially involved in epileptogenesis. To assess the potential pathogenetic role of microglial MMPs and TIMPs in seizure induction, twenty-four dogs suffering from different intracranial diseases with and without seizure activity were comparatively examined. Microglial cells were isolated by density gradient centrifugation and their expression profiles of MMP-2, MMP-9, MMP-12, MMP-13, MMP-14, TIMP-1, TIMP-2, and RECK (reversion-inducing cysteine-rich protein with Kazal motifs) were examined via quantitative real-time PCR (qPCR). Interestingly, a significant up-regulation of TIMP-2 expression was found for the first time in dogs suffering from seizures. In conclusion, microglial TIMP expression might be involved in seizure generation.  相似文献   
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An N-balance experiment was conducted to test the hypothesis that d-Methionine (d-Met) has the same bioavailability and efficacy as l-Methionine (l-Met) when fed to weanling pigs. A Met-deficient basal diet containing 0.24% standardized ileal digestible (SID) Met was formulated. Six additional diets were formulated by adding 0.036%, 0.072%, or 0.108% d-Met or l-Met to the basal diet, and these diets, therefore, contained 77%, 87%, or 97% of the requirement for SID Met. Fifty-six barrows (10.53 ± 1.17 kg) were housed in metabolism crates and allotted to the seven diets with eight replicate pigs per diet. Feces and urine were collected quantitatively with 7-d adaptation and 5-d collection periods. Blood and tissue samples from pigs fed the basal diet and pigs fed diets containing 0.108% supplemental Met were collected on the last day. Results indicated that N retention (%) linearly increased (P < 0.01) as supplemental d-Met or l-Met increased in diets. Based on N retention (%) as a response, the linear slope-ratio regression estimated the bioavailability of d-Met relative to l-Met to be 101% (95% confidence interval: 57%–146%). The villus height and crypt depth in the jejunum were not affected by the Met level or Met source. Total antioxidant capacity or thiobarbituric acid reactive substance concentrations in plasma or tissue samples from pigs fed the control diet or diets containing 0.108% supplemental d-Met or l-Met were not different. Abundance of mRNA for some AA transporters analyzed in intestinal mucosa of pigs also did not differ. Therefore, it is concluded that d-Met and l-Met are equally bioavailable for weanling pigs.  相似文献   
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