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1.
Walking ability is significantly lower in hemodialysis patients compared to healthy people. Decreased walking ability characterized by slow walking speed is associated with adverse clinical events, but determinants of decreased walking speed in hemodialysis patients are unknown. The purpose of this study was to identify factors associated with slow walking speed in ambulatory hemodialysis patients. Subjects were 122 outpatients (64 men, 58 women; mean age, 68 years) undergoing hemodialysis. Clinical characteristics including comorbidities, motor function (strength, flexibility, and balance), and maximum walking speed (MWS) were measured and compared across sex-specific tertiles of MWS. Univariate and multivariate logistic regression analyses were performed to examine whether clinical characteristics and motor function could discriminate between the lowest, middle, and highest tertiles of MWS. Significant and common factors that discriminated the lowest and highest tertiles of MWS from other categories were presence of cardiac disease (lowest: odds ratio [OR] = 3.33, 95% confidence interval [CI] = 1.26–8.83, P<0.05; highest: OR = 2.84, 95% CI = 1.18–6.84, P<0.05), leg strength (OR = 0.62, 95% CI = 0.40–0.95, P<0.05; OR = 0.57, 95% CI = 0.39–0.82, P<0.01), and standing balance (OR = 0.76, 95% CI = 0.63–0.92, P<0.01; OR = 0.81, 95% CI = 0.68–0.97, P<0.05). History of fracture (OR = 3.35, 95% CI = 1.08–10.38; P<0.05) was a significant factor only in the lowest tertile. Cardiac disease, history of fracture, decreased leg strength, and poor standing balance were independently associated with slow walking speed in ambulatory hemodialysis patients. These findings provide useful data for planning effective therapeutic regimens to prevent decreases in walking ability in ambulatory hemodialysis patients.  相似文献   
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Angiotensin converting enzyme (ACE) of vascular endothelial cells is suggested to control vascular wall tonus through the conversion of angiotensin I (AI) to angiotensin II (AII) and the degradation of bradykinin. To obtain more insight into the pathophysiological significance of ACE of vascular endothelial cells, we studied the regulation of ACE produced by cultured human umbilical vein endothelial cells (EC). Phorbol 12-myristate 13-acetate (PMA) increased the cellular and medium ACE activity, accompanied by a marked morphological change in EC. N'-O'-dibutylyladenosine 3';5'-cyclic monophosphate (db-cAMP) increased only the cellular ACE activity and not the medium ACE activity. The effect of isoproterenol with 0.1mM theophylline mimicked that of db-cAMP. These findings suggest that PMA and cAMP-related agents participate in the control of vascular wall tonus through the positive regulation of ACE produced by vascular endothelial cells.  相似文献   
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In addition to the known triterpene motiol, hopenol-b (hop-22(29)-en-3β-ol) was isolated from the whole herb of Euphorbia supina. It has not been found previously in nature, though it has been prepared by both synthetic and biosynthetic methods.  相似文献   
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L C Strong  H Matsunaga 《Cytobios》1976,17(67-68):177-181
Spontaneous tumour-bearing mice of the C3H/St and subline C3HB/St inbred strains received injections of three nucleosides, adenosine, 6-methyl adenosine, and 5-methyl cytidine, prepared in the same molecular concentration as they had occurred in an alcohol-soluble liver extract which in previous work had suppressed tumour growth. Two transmissible entities appear to be present and they show different degrees of effect upon the growth and regression of spontaneous tumours of mammary gland origin (adenocarcinoma). The first transmissible entity (TE) occurred in the lineal descent of mice following injection of the liver extract. The second entity (TE2) appeared following injection of 5-methyl cytidine. TE manifested its maximum effect in suppressing cancer in mice during the 20th generation of a lineal descent following the injection of the original liver extract into a mother of the cancer proband. TE2 appears to be optimal in controlling cancer in the F11 generation of a second lineal descent derived from an original cancer proband of the C3H/St inbred strain injected with 5-methyl cytidine.  相似文献   
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Whole cells of Chlorella vulgaris and Clostridium butyricum were co-immobilized in 2% agar gel. NADP was suitable as an electron carrier. The rate of hydrogen evolution increased with increasing NADP concentration. The optimum conditions for hydrogen evolution were pH 7.0 and 37°C. The immobilized C. vulgaris-NADP-immobilized Cl. butyricum system continuously evolved hydrogen at a rate of 0.29–1.34 μmol/h per mg Chl for 6 days. On the other hand, the system without NADP evolved only a trace amount of hydrogen.  相似文献   
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1. Stomachs of adult teleosts and elasmobranchs reacted to an anti-embryonic chicken pepsinogen antiserum (anti-ECPg) as well as to an anti-adult chicken pepsinogen antiserum (anti-ACPg). 2. Zymograms and immunoblots of stomach extracts revealed that anti-ECPg- and anti-ACPg-reactive substances possess peptic activity. 3. The possible relationship between anti-ECPg-reactive pepsinogens in fish and prochymosins in higher vertebrates is discussed.  相似文献   
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Melanin concentrating hormone (MCH) is a heptadecapeptide synthesized by the hypothalamus and secreted by the neurohypophysis of the teleost pituitary gland. MCH stimulates melanosome aggregation within teleost melanocytes but also exhibits MSH-like (melanosome dispersing) activity on tetrapod (frog and lizard) melanocytes. We have synthesized a number of MCH analogues to determine the essential features of the primary structure necessary to stimulate either melanosome aggregation or dispersion in fish or tetrapod melanocytes, respectively. An analysis of the potencies and actions of these analogues on vertebrate melanocytes is provided and demonstrates that the two activities have different structural requirements.  相似文献   
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Listeria monocytogenes possessed glucose oxidase and NADH oxidase activities in whole cells and lysed protoplasts respectively. The NADH oxidase activity sedimented with the membrane fraction and was inhibited by the respiratory inhibitors rotenone, 2-heptyl-4-hydroxy-quinoline-N-oxide and cyanide, suggesting the presence of a membrane associated respiratory chain.  相似文献   
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