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641.
Background
Pelodera (Rhabditis) strongyloides is a small saprophytic nematode that lives in decaying organic matter. On rare occasions, it can invade the mammalian skin, causing a pruritic, erythematous, alopecic and crusting dermatitis on skin sites that come into contact with the ground. Diagnosis of the disease is based on case history (a dog living outdoors on damp straw bedding) with characteristic skin lesions and on the demonstration of typical larvae in skin scrapings or biopsy. Pelodera (rhabditic) dermatitis cases have been reported mainly from Central European countries and the United States. 相似文献642.
Fernando Carrasquedo Mario Glanc Cesar G.Fraga 《Free radical biology & medicine》1999,26(11-12):1587-1590
A growing amount of scientific evidence supports the participation of oxygen radicals in heart disease and, consequently, a protective effect of vitamin E (VE), beta-carotene (BC), and other antioxidants. The aim of this study was to correlate plasma VE and BC concentration with the clinical course of the acute myocardial infarction (AMI). We evaluated 120 patients that were admitted at the coronary units within 12 h after the development of AMI symptoms. The AMI was diagnosed by clinical and biochemical criteria and by electrocardiography and echocardiography. Plasma VE and BC concentration was determined by high performance liquid chromatography. The patients were separated according to the plasma concentration of VE (group H, VE > 17.5 microM; group L, VE < 17.5 microM). Clinical history of patients, age, sex, associated cardiovascular risk factors, AMI localization, hemodynamic class, and the treatment received were similar between different groups. The blood levels of creatine phosphokinase (CK) evaluated either 24- or 48-h after admittance, were higher in group L than in group H (24 h: H = 436 +/- 31 U/ml vs. L = 642 +/- 84 U/ml; p < .005; 48 h: H = 242 +/- 21 U/ml; L = 423 +/- 82 U/ml, p < 0.005). The number of deflexions in the electrocardiogram at admittance (ECG-D) was significantly higher in group L than in group H (4.7 +/- 0.3 vs. 3.7 +/- 0.2; p < .005). The number of new Q waves in the ECG of release (ECG-Q) was higher in group L than in group H (2.9 +/- 0.3 vs. 2.2 +/- 0.2; p < .05). The number of segments affected in the echocardiograms (EC-S) was: L = 5.3 +/- 0.6 vs. H = 4.4 +/- 0.2; p = 0.11. No significant differences in CK levels, ECG-D, ECG-Q, and EC-S were observed when the patients were separated according their plasma BC levels. These results indicate that a high concentration of plasma VE, but not BC, was associated with a diminution in the creatine phosphokinase release and with the AMI extension. 相似文献
643.
644.
Two novel dihydroanthracenones, menamesone A and menamesone B, and two known hydronaphthalenones of a rare type, rubiasins B and C, have been isolated from the roots of Plocama pendula, a paleoendemism of the Canary Islands. 相似文献
645.
Amanda Fraga Jorge Moraes José Roberto da Silva Evenilton P. Costa Jackson Menezes Itabajara da Silva Vaz Jr Carlos Logullo Rodrigo Nunes da Fonseca Eldo Campos 《International journal of biological sciences》2013,9(8):842-852
The physiological roles of polyphosphates (poly P) recently found in arthropod mitochondria remain obscure. Here, the possible involvement of poly P with reactive oxygen species generation in mitochondria of Rhipicephalus microplus embryos was investigated. Mitochondrial hexokinase and scavenger antioxidant enzymes, such as superoxide dismutase, catalase, and glutathione reductase were assayed during embryogenesis of R. microplus. The influence of poly P3 and poly P15 were analyzed during the period of higher enzymatic activity during embryogenesis. Both poly Ps inhibited hexokinase activity by up to 90% and, interestingly, the mitochondrial membrane exopolyphosphatase activity was stimulated by the hexokinase reaction product, glucose-6-phosphate. Poly P increased hydrogen peroxide generation in mitochondria in a situation where mitochondrial hexokinase is also active. The superoxide dismutase, catalase and glutathione reductase activities were higher during embryo cellularization, at the end of embryogenesis and during embryo segmentation, respectively. All of the enzymes were stimulated by poly P3. However, superoxide dismutase was not affected by poly P15, catalase activity was stimulated only at high concentrations and glutathione reductase was the only enzyme that was stimulated in the same way by both poly Ps. Altogether, our results indicate that inorganic polyphosphate and mitochondrial membrane exopolyphosphatase regulation can be correlated with the generation of reactive oxygen species in the mitochondria of R. microplus embryos. 相似文献
646.
The calcium/calmodulin-regulated Ca-ATPase of the plasma membraneis implicated in Paramecium chemosensory transduction. Calmodulinantisense oligonucleotides electroporated into Paramecium disruptchemosensory responses to sodium acetate but not to ammoniumchloride. Chem. Senses 21: 5558, 1996. 相似文献
647.
Bases and spaces: resources on the web for accessing the draft human genome - II - After publication of the draft 下载免费PDF全文
Colin AM Semple 《Genome biology》2001,2(6):reviews2001.1-reviews20016
The volume of human genome sequence and the variety of web-based tools to access it continue to grow at an impressive rate, but a working knowledge of certain key resources can be sufficient to get the most from your genome. This article provides an update to Genome Biology 2000, 1(4):reviews2001.1-2001.5. 相似文献
648.
Anapaula Sommer Vinagre Ana Paula Nunes do Amaral Fabiana Pinto Ribarcki Eliane Fraga da Silveira Eduardo Prico 《Comparative biochemistry and physiology. Part A, Molecular & integrative physiology》2007,146(4):514
The aim of this study was to analyze the seasonal variations of carbohydrate and lipid metabolism of the ghost crab Ocypode quadrata (Fabricius, 1787) on a sandy beach in the southern region of Brazil. Crabs and hemolymph samples were collected monthly in the field. Hepatopancreas, gills, gonads and claw muscles were used for glycogen determination. In males, blood glucose levels increased in the summer and in the winter. The glycogen values increased significantly in the hepatopancreas in the winter, but remained constant in the muscle, gonads and gills. In females, hemolymph glucose levels, glycogen values in the hepatopancreas and in the gills remained constant throughout the year; however, muscular glycogen increased in the spring and gonad glycogen decreased in the summer. Hemolymph triglyceride levels of males and females and total cholesterol of males decreased significantly in the spring. In females, a significant increase of total cholesterol levels was found in the winter. The findings suggest that in O. quadrata lipids seem to be an important reserve of energy used during reproduction, both in males and females, while glycogen may be used during periods of intense activity or fasting. 相似文献