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31.
The objective of this study was to determine the effects of cellobiose and monensin on the in vitro fermentation of organic acids (L-aspartate, fumarate, and DL-malate) by mixed ruminal bacteria. Ruminal fluid was collected from a steer fed 36.7 kg of forage and 4.5 kg of concentrate supplement once per day. Ruminal fluid was centrifuged to sediment feed particles and protozoa, and the resulting supernatant, which contained bacteria, was added (33%, vol/vol) to anaerobic media (500 ml). Incubations (n = 2) were performed in batch culture at 39 degrees C and sampled at 0, 2, 4, 6, 8, 12, and 24 h. Organic acids were added to achieve a final concentration of 7.5 mM. Cellobiose was added to obtain a final concentration of 5 mM, and monensin dissolved in ethanol was included at concentrations of 0 or 5 ppm. Addition of cellobiose to organic acid fermentations increased the rate of organic acid utilization by the mixed bacterial population. Total concentrations of volatile fatty acids were increased by the addition of cellobiose to all fermentations. A lag period (< or = 8 h) occurred in fermentations that were treated with monensin before organic acids were utilized. Total concentrations of volatile fatty acids were increased, and the acetate to propionate ratio was decreased, by monensin treatment. When cellobiose and monensin were added together, propionate production and organic acid utilization were increased. Both cellobiose and monensin affected the in vitro fermentation of organic acids by mixed ruminal bacteria by providing a carbon and energy source and by influencing electron disposal.  相似文献   
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Endoscopic treatment of acute pancreatitis has been proposed in different conditions: acute biliary pancreatitis, pancreatitis related to pancreas divisum or in case of pseudocysts. The efficacy of such endoscopic procedure is discussed.  相似文献   
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In a study of 32 unrelated Arab patients with juvenile myoclonic epilepsy (JME), we compared the frequencies of human leukocyte antigen (HLA) class I and II alleles with those of unrelated healthy controls. A significant difference between the phenotypic frequencies in JME patients and controls was observed for DRW13, the split of DRW6 (37.5 vs 11% of controls). The strength of association as measured by the relative risk was 4.85 for this antigen (p = 0.002). The possible association of JME with HLA-DRW6 recently reported in Caucasians was confirmed in this study. This finding speaks for the homogeneity of the disease among Arabic and Caucasian JME patients. The existence of this association is evidence of a locus in the HLA region that influences expression of JME.  相似文献   
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We analyzed 79 consecutive patients with aneurysms and found a patient who lacked type III collagen. Collagen was extracted from the skin, and the lack of type III collagen was determined by means of sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE). Only 1 of the 79 patients was found to lack type III collagen. This patient was a 55-year-old man who had sustained an abdominal aortic aneurysm and aortic dissection. He did not show any of the typical clinical symptoms of Ehlers-Danlos syndrome type IV, such as hyperextensible skin and joints. He had none of the usual risk factors nor any clear family history of the syndrome. Furthermore, his collagen fibrils demonstrated a homogeneous appearance. This case may represent a new form of type III collagen deficiency.  相似文献   
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Contents of lipids (cholesterol CS, triglycerides) as well as levels of CS of lipoproteins of different density and of apolipoproteins A1 and B were measured in blood serum of 31 patients in different periods after of ischemic stroke. The majority of the indices studied were significantly decreased in men in acute periods of the stroke, especially in 8-21 days after the stroke development. Meanwhile, the levels of lipids, CS lipoproteins of both low and very low densities were increased later. Contents of CS of antiatherogenic lipoproteins of high density (HDLP) was low in different periods after the development of disorders of cerebral circulation. This confirms the concept that low level of HDLP is one of the risk factors of ischemic stroke. Decrease of the levels of both lipids and CS of lipoproteins of different density was more pronounced in patients with more severe atherosclerotic damages of the main cerebral arteries. Disorders of metabolism of lipoproteins in ischemic disorders of cerebral circulation are discussed with reference to literary data taking into consideration their heterogeneity. Genetically determined pathology of certain apolipoproteins plays a key role factor in the development of early atherosclerosis and in the elucidation of biochemical markers of the primary damages of cerebral vessels.  相似文献   
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The expression of membrane immunoglobulin (mIg) was examined in three cloned MPC11-derived mouse myeloma cell lines. Membrane immunofluorescence studies demonstrated that IgG2b producer cells (P1) had complete IgG molecules, L-chain producer (L1) had only L-chain determinants and nonproducer (NP2) did not have any Ig determinants on the cell surface. An Ig receptor, with characteristics different from B lymphocyte Fc receptor, has been found to be present on secreting cells (P1 or L1), but not on the NP2 cell variant. The data reported in the present paper indicate that the expression of mIg and of the Ig receptor molecule is clearly correlated with the process of secretion. In the light of previous data reported on Ig secretion, a model is proposed which correlates the process of secretion with the expression not only of mIg, but also of the receptor for Ig.  相似文献   
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