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排序方式: 共有489条查询结果,搜索用时 31 毫秒
101.
Eva Román Cristina García-Galcerán Teresa Torrades Silvia Herrera Ana Marín Maite Do?ate Edilmar Alvarado-Tapias Jorge Malouf Laura Nácher Ricard Serra-Grima Carlos Guarner Juan Cordoba German Soriano 《PloS one》2016,11(3)
Patients with cirrhosis often have functional limitations, decreased muscle mass, and a high risk of falls. These variables could improve with exercise. The aim was to study the effects of moderate exercise on functional capacity, body composition and risk of falls in patients with cirrhosis. Twenty-three cirrhotic patients were randomized to an exercise programme (n = 14) or to a relaxation programme (n = 9). Both programmes consisted of a one-hour session 3 days a week for 12 weeks. At the beginning and end of the study, we measured functional capacity using the cardiopulmonary exercise test, evaluated body composition using anthropometry and dual energy X-ray absorptiometry, and estimated risk of falls using the Timed Up&Go test. In the exercise group, cardiopulmonary exercise test showed an increase in total effort time (p<0.001) and ventilatory anaerobic threshold time (p = 0.009). Upper thigh circumference increased and mid-arm and mid-thigh skinfold thickness decreased. Dual energy X-ray absorptiometry showed a decrease in fat body mass (-0.94 kg, 95%CI -0.48 to -1.41, p = 0.003) and an increase in lean body mass (1.05 kg, 95%CI 0.27 to 1.82, p = 0.01), lean appendicular mass (0.38 kg, 95%CI 0.06 to 0.69, p = 0.03) and lean leg mass (0.34 kg, 95%CI 0.10 to 0.57, p = 0.02). The Timed Up&Go test decreased at the end of the study compared to baseline (p = 0.02). No changes were observed in the relaxation group. We conclude that a moderate exercise programme in patients with cirrhosis improves functional capacity, increases muscle mass, and decreases body fat and the Timed Up&Go time.Trial Registration: ClinicalTrials.gov NCT01447537相似文献
102.
Structure and chromosomal mapping of a highly polymorphic repetitive DNA sequence from the pseudoautosomal region of the mouse sex chromosomes 总被引:5,自引:0,他引:5
K Harbers U Francke P Soriano R Jaenisch U Müller 《Cytogenetics and cell genetics》1990,53(2-3):129-133
The pseudoautosomal region of the Mov15 mouse strain is marked by a Moloney murine leukemia provirus. The sequences flanking the Mov15 provirus were molecularly cloned and shown to consist of a tandemly repeated sequence of 31 nucleotides. Copy number variation of this repeat most likely accounts for the polymorphism in the mouse pseudoautosomal region detected with a probe from the flanking sequences. In situ hybridization to metaphase chromosomes showed heavy labeling of the pairing region of the X and Y chromosomes. The repetitive sequence was also found at the subtelomeric region of three autosomes. A similar level of amplification as the one seen on the sex chromosomes seems to be present on chromosomes 9 and 13. Lower copy number appear to be present on chromosome 4. 相似文献
103.
S ummary . Ammonia oxidizing autotrophic nitrifying bacteria in soil samples from 3 classical Rothamsted fields and elsewhere were counted by a modified 2-layered silica gel plating method. Counts ranged from 0-18000/g of dry soil, the maximum number being found in the Broadbalk farmyard manure plot. Nitrosomonas europaea was isolated in pure culture and detected only in soils treated with dung or other organic fertilizer. Nitrosocystis coccoides and Nitrosospira spp. were found in other soils. Nitrobacter spp. were present in many soils and of the 18 pure cultures isolated there seemed to be 3, or possibly 4, different colony types. 相似文献
104.
Isolation of ammonia-oxidizing autotrophic bacteria 总被引:18,自引:0,他引:18
105.
J Tor J M Llibre M Carbonell R Muga A Ribera V Soriano B Clotet M Sabriá M Foz 《BMJ (Clinical research ed.)》1990,301(6761):1130-1133
OBJECTIVE--To determine the extent of transmission of hepatitis C virus in sexual partners of intravenous drug misusers and to examine the relation between the prevalences of HIV, hepatitis B virus, and hepatitis C virus infections in homosexual men and intravenous drug misusers and their sexual partners. DESIGN--Serum samples collected between 1984 and 1988 were tested for hepatitis B virus markers and antibodies against hepatitis C virus by enzyme linked immunosorbent assay (ELISA) and for HIV antibody by enzyme immune analysis and western blotting. SETTING--Large referral university hospital with an external AIDS clinic in the metropolitan area of Barcelona, Spain. SUBJECTS--243 Intravenous drug misusers, 143 of their regular heterosexual partners, and 105 homosexual men. MAIN OUTCOME MEASURES--Prevalences of hepatitis C virus, hepatitis B virus, and HIV infections. RESULTS--In all, 178 of the 243 (73%) intravenous drug misusers, 16 out of 143 (11%) of their partners, and 17 of the 105 (16%) homosexual men had antibodies against hepatitis C virus. The presence of hepatitis C virus infection was unrelated to sex, age, the presence of HIV or hepatitis B virus infections, or the Centers for Disease Control stage of HIV. In sexual partners of intravenous drug misusers there were strong correlations between the presence of hepatitis C virus infection and that of HIV (p = 0.001) and hepatitis B virus (p = 0.013) infections. CONCLUSIONS--Intravenous drug misusers have a high risk of acquiring hepatitis C virus, hepatitis B virus, and HIV infections, but the presence of hepatitis C virus infection seems to be unrelated to the presence of the other two viruses. Homosexual men have a high prevalence of HIV and hepatitis B virus infections with a low prevalence of hepatitis C virus infection, the presence of which is not related to that of the other two infections. Conversely, heterosexual partners of intravenous drug misusers have low prevalences of the three virus infections, but the presence of hepatitis C virus infection correlates significantly with the presence of HIV and hepatitis B infections. The rate of sexual transmission of hepatitis C virus seems to be low, even in partners of people known to be seropositive for this virus. 相似文献
106.
Monique Gabriela das Chagas Faustino Alves Celina Maria Pinto G. Dore Allisson Jhonatan G. Castro Marília Silva do Nascimento Ana Katarina M. Cruz Eliane M. Soriano Norma M. Barros Benevides Edda Lisboa Leite 《Journal of applied phycology》2012,24(5):1217-1227
Polysaccharides, galactans, obtained from edible red seaweed Hypnea musciformis were characterized by molecular weight and infrared spectroscopy analysis and were evaluated for antioxidant activity in vitro and for their effects on cell viability. The main components were galactose and sulfate presenting low protein contamination. These sulfated galactans (F1.0) showed a polydisperse profile, and signs in infrared analysis were attributed to a sulfate ester S?=?O bond, the presence of a 3,6-anhydrogalactose C–O bond, nonsulfated β-d-galactose, and a C–O–SO4 bond in galactose C4. The NMR analysis showed signals at about 95 and 92 attributed to anomeric carbon of 4-linked 3,6-anhydro-α-d-galactopyranose residue of κ-carrageenans and 4-linked 3,6-anhydro-α-d-galactopyranose2-sulfate of ι-carrageenans. Sulfated galactan F1.0 showed strong antioxidant activity under lipid peroxidation assay where F1.0 at 8 mg mL?1 promoted 57.92% peroxidation inhibition and displayed the scavenging activity on hydroxyl radicals in a dose-dependent manner leading to 32.5% scavenging of these radicals when 5 mg mL?1 of sulfated galactan F1.0 was used. The sulfated galactan fraction also exhibited strong inhibition on the H2O2-induced hemolysis model. Sulfated galactan F1.0 displayed low cytotoxic action in 3 T3 cells and moderate antitumoral action in HeLa cells. These results suggest that sulfated galactan F1.0 from H. musciformis has antioxidant potential, which is a great effect for a compound used as food and in the food industry. 相似文献
107.
Raquel Cunill Joan-Manuel Soriano Marie-Claude Bal Albert Pèlachs Ramon Pérez-Obiol 《Vegetation History and Archaeobotany》2012,21(4-5):373-384
The principal objective of this research is to determine the maximum elevation reached by the treeline, as well as its altitudinal variations and composition throughout the Holocene, in a high mountain zone of the Pyrenean range. The temporal intervals of pedoanthracological data begin in 11000?cal. b.p. with the oldest dated charcoal, permitting a study of the entire Holocene period with the capacity to analyze climatic and anthropic situations. This is the first study to apply analysis of soil charcoals to the meridional slope of the Pyrenees for this purpose, and also its first use in research on the Iberian Peninsula. Eight pedoanthracological sites were sampled in a transect from 2,000 to 2,600?m altitude, with an altitudinal resolution of 100?m. The spatial precision provided by this proxy allows us to show that the maximum extension of the upper forest line was 400?m above the current line. This suggests a complete change in the landscape of a zone that is now covered with pasture from 2,000?m to the peak (2,593?m). Although pre-Neolithic fires appear to have a primarily climatic component, the fire origins during and after this period are more complex and far from being explained by a single, unequivocal cause. 相似文献
108.
The objective of this work was to produce doubled haploid plants from durum wheat through the induction of androgenesis. A
microspore culture technique was developed and used to produce fertile doubled haploid plants of agronomic interest. Five
cultivars, one selected line, plus a collection of 20 F1 crosses between different genotypes of high breeding value were used. Studies on several factors such as pre-treatments and
media components were carried out in order to develop a protocol to regenerate green haploid plantlets. Anthers were pre-treated
in 0.7 M mannitol. Microspores, from anther maceration, were plated on a C17 induction culture medium with ovary co-culture. The optimum regeneration medium J25–8 was used. From 35 microspore isolations,
407 green plantlets were obtained. With this technique mature embryos were obtained. Green plants were regenerated from all
genotypes used and approximately 67% of them were spontaneously doubled haploids. Some haploids and a very few polyploids
plants were obtained. From the 407 plants, 275 were completely fertile and gave enough seeds to be assayed in the field. This
protocol could be used complementary to or instead of the intergeneric crossing with maize as an economically feasible method
to obtain doubled haploids from most durum wheat genotypes. 相似文献
109.
Cliff C. Cheng Gerald W. Shipps Zhiwei Yang Binyuan Sun Noriyuki Kawahata Kyle A. Soucy Aileen Soriano Peter Orth Li Xiao Paul Mann Todd Black 《Bioorganic & medicinal chemistry letters》2009,19(23):6507-6514
The biotin carboxylase (AccC) is part of the multi-component bacterial acetyl coenzyme-A carboxylase (ACCase) and is essential for pathogen survival. We describe herein the affinity optimization of an initial hit to give 2-(2-chlorobenzylamino)-1-(cyclohexylmethyl)-1H-benzo[d]imidazole-5-carboxamide (1), which was identified using our proprietary Automated Ligand Identification System (ALIS).1 The X-ray co-crystal structure of 1 was solved and revealed several key interactions and opportunities for further optimization in the ATP site of AccC. Structure Based Drug Design (SBDD) and parallel synthetic approaches resulted in a novel series of AccC inhibitors, exemplified by (R)-2-(2-chlorobenzylamino)-1-(2,3-dihydro-1H-inden-1-yl)-1H-imidazo[4,5-b]pyridine-5-carboxamide (40). This compound is a potent and selective inhibitor of bacterial AccC with an IC50 of 20 nM and a MIC of 0.8 μg/mL against a sensitized strain of Escherichia coli (HS294 E. coli). 相似文献
110.
The prediction of gains from selection allows the comparison of breeding methods and selection strategies, although these estimates may be biased. The objective of this study was to investigate the extent of such bias in predicting genetic gain. For this, we simulated 10 cycles of a hypothetical breeding program that involved seven traits, three population classes, three experimental conditions and two breeding methods (mass and half-sib selection). Each combination of trait, population, heritability, method and cycle was repeated 10 times. The predicted gains were biased, even when the genetic parameters were estimated without error. Gain from selection in both genders is twice the gain from selection in a single gender only in the absence of dominance. The use of genotypic variance or broad sense heritability in the predictions represented an additional source of bias. Predictions based on additive variance and narrow sense heritability were equivalent, as were predictions based on genotypic variance and broad sense heritability. The predictions based on mass and family selection were suitable for comparing selection strategies, whereas those based on selection within progenies showed the largest bias and lower association with the realized gain. 相似文献