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排序方式: 共有2322条查询结果,搜索用时 186 毫秒
961.
Gaertner H Lebeau O Borlat I Cerini F Dufour B Kuenzi G Melotti A Fish RJ Offord R Springael JY Parmentier M Hartley O 《Protein engineering, design & selection : PEDS》2008,21(2):65-72
The HIV coreceptor CCR5 is a validated target for both the prevention and therapy of HIV infection. PSC-RANTES, an N-terminally modified analogue of one of the natural chemokine ligands of CCR5 (RANTES/CCL5), is a potent inhibitor of HIV entry into target cells. Here, we set out to engineer the anti-HIV activity of PSC-RANTES into another natural CCR5 ligand (MIP-1beta/CCL4), by grafting into it the key N-terminal pharmacophore region from PSC-RANTES. We were able to identify MIP-1beta/CCL4 analogues that retain the receptor binding profile of MIP-1beta/CCL4, but acquire the very high anti-HIV potency and characteristic inhibitory mechanism of PSC-RANTES. Unexpectedly, we discovered that in addition to N-terminal structures from PSC-RANTES, the side chain of Lys33 is also necessary for full anti-HIV potency. 相似文献
962.
Reviews the book, Economics and psychology: A promising new cross-disciplinary field edited by Bruno S. Frey and Alois Stutzer (see record 2007-00637-000). The editors' goal in this book was to review some recent applications of psychological theories in the field of economics. Given economics' high reliance on agency theory, this book provides a fresh look into what standard economics has had a difficult time explaining: what economists have called "errors" in individual behaviour and decision making. The gist of the book focuses on showing that these errors are in fact part of the human make-up, and the contributors use psychological theories and evidence to build a new economics paradigm. The book purports to question the assumption of the human as a rational being, to show the value of experimental methods in economics, and to make well-being a worthy outcome in economics. This book is of interest to economists who have an interest in microeconomics and want to break free from the narrow focus of agency theory. It is also of interest to psychologists who want to extend their work on prosocial behaviour and well-being to include economic and institutional considerations as part of their accounts. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
963.
964.
Teixeira Nunes F de Campos G Xavier de Paula SM Merhi VA Portero-McLellan KC da Motta DG de Oliveira MR 《Hemodialysis international. International Symposium on Home Hemodialysis》2008,12(1):45-51
To characterize the nutritional status of renal failure patients and its relationship with hemodialysis adequacy measured by Kt/V, a study was carried out with a population of 44 adult patients with renal failure and mean age 51+/-15 years. Anthropometric data, such as dry weight, height, arm circumference, triceps skinfold thickness, mid-arm muscle circumference, and body mass index were assessed, and biochemical tests were conducted for urea, potassium, creatinine, serum albumin, and phosphorus levels, in addition to hemogram and quarterly urea reduction rate average (Kt/V). In order to evaluate calorie intake, a dietary questionnaire on habitual daily food ingestion was administered, taking into consideration the hemodialysis date. The patients were divided into 2 separate groups for the statistical analysis, with 50% of the patients in each group: A (Kt/V<1.2) and B (Kt/V>1.2). The data were tabulated as mean and standard deviation, with differences tested by Student's t test. The correlations between variables were established by the coefficient p of Pearson. Most of the patients (43%) were considered eutrophic, based on the BMI, and presented inadequate calorie intake, corresponding to 88.5+/-24% (30.8 kcal/kg actual weight) of the total energy required and adequate protein intake, reaching 109.9+/-40% of the recommended daily allowance (1.24 g/kg of actual weight). There was a correlation of Kt/V with anthropometric parameters such as body mass index, arm circumference, and mid-arm muscle circumference. The biochemical parameters related to dialysis adequacy were albumin, ferritin, and urea (predialysis). Well-dialyzed patients presented better levels of serum albumin. There was an influence of gender and age on correlations of the analyzed variables. Female and younger patients presented better dialysis adequacy. The dialysis adequacy was related to the nutritional status and influenced by the protein intake and body composition. Gender and age had an important influence in the dialysis adequacy, as men presented lower dialysis adequacy and younger adults presented better dialysis adequacy. Further research is necessary to understand better how to facilitate effective and efficient techniques for the nutritional status assessment of hemodialysis patients. 相似文献
965.
Warakulwit C Nguyen T Majimel J Delville MH Lapeyre V Garrigue P Ravaine V Limtrakul J Kuhn A 《Nano letters》2008,8(2):500-504
Short carbon nanotubes have been modified selectively on one end with metal using a bulk technique based on bipolar electrochemistry. A stabilized suspension of nanotubes is introduced in a capillary containing an aqueous metal salt solution, and a high electric field is applied to orientate and polarize the individual tubes. During their transport through the capillary under sufficient polarization (30 kV), each nanotube is the site of water oxidation on one end and the site of metal ion reduction on the other end with the size of the formed metal cluster being proportional to the potential drop along the nanotube. 相似文献
966.
Corde S Adam JF Biston MC Joubert A Charvet AM Estève F Le Bas JF Elleaume H Balosso J 《Radiation protection dosimetry》2005,117(4):425-431
An experimental binary radiotherapy proposes the concomitant use of a high-Z compound and synchrotron X rays for enhancing radiation dose selectively in tumours by a photoelectric effect. This study aimed at measuring the resulting dose enhancement in irradiated material. A doped Fricke gel dosemeter model was manufactured with 10 mg ml(-1) of iodine (Telebrix) or barium (Micropaque). Samples were irradiated with a monochromatic synchrotron beam at 33.5, 50, 65 and 80 keV. The ensuing enhancement of the sensitivity of the dosemeter was derived from the nuclear magnetic resonance relaxation rates measured at different X-ray doses. Our results demonstrate (1) the preservation of a linear relationship between relaxation rates and X-ray doses for dosemeters doped with high-Z atoms and (2) a clear energy-dependent sensitivity enhancement for barium-doped Fricke gels. This enhancement was neither reproducible with iodinated compounds nor clearly related to the expected dose enhancement factor. However 1% barium sulphate in the gel could significantly improve the gel's response when it was irradiated by low-energy X rays. 相似文献
967.
Terrier N Senécal L Dupuy AM Jaussent I Delcourt C Leray H Rafaelsen S Bosc JY Maurice F Canaud B Cristol JP 《Hemodialysis international. International Symposium on Home Hemodialysis》2005,9(2):159-168
Background: Inflammation and malnutrition are recognized as important risk factors for cardiovascular disease (CVD) in hemodialysis (HD) patients. Owing to substantial short‐term variability of serum C‐reactive protein (CRP), more reliable markers of malnutrition–inflammation complex syndrome should be sought with stronger associations with the risk of CVD in HD patients. We therefore explored the clinical relevance of a composite inflammatory index (prognostic inflammatory and nutritional index [PINI]) and of muscle protein mass indicators, derived from creatinine kinetics. Methods: This cross‐sectional study included 177 HD patients (89 women and 88 men; median age, 67.73 years). CVD and risk factors were assessed using medical charts, clinical examination, and biochemical measurements performed at inclusion. Lean body mass (LBM) was derived from creatinine kinetic modeling, whereas PINI was calculated as the ratio (CRP ×α1‐acid‐glycoprotein)/(albumin × transthyretin). Patients were divided according to the presence or absence of established CVD. Results: The traditional risk factors diabetes (odds ratio [OR], 5.83; p = 0.0045) and smoking (OR, 3.50; p < 0.02) were associated with an increase in prevalent CVD. Low transthyretin (OR, 3.79; p < 0.02) and high levels of CRP (OR, 2.70; p < 0.05), PINI (OR, 3.44; p < 0.02), observed LBM (OR, 3.01; p < 0.05), and the ratio of observed/expected LBM (OR, 4.24; p < 0.01) were associated with CVD after adjustment for age, sex, dialysis center, and dialysis vintage. After additional adjustment for diabetes and smoking, only PINI (OR, 2.85; p = 0.0446) and observed/expected LBM (OR, 2.96; p = 0.0361) were still significant. Conclusion: PINI and LBM are associated with increased relative risk for having CVD and could be used routinely to examine the degree of severity of malnutrition inflammation complex syndrome. 相似文献
968.
Flow cytometry (FCM), combined with staining using two fluorochromes (propidium iodide, PI, or SYBR Green II RNA gel stain, SYBR-II), was used to assess nucleic acid injuries to chlorinated drinking water bacteria. Highly fluorescent SYBR-II-stained bacteria were converted to bacteria with low fluorescence after chlorination. PI staining of bacteria exposed to different doses of chlorine showed membrane permeabilisation ([Cl2] < 0.2 mg L(-1)) and nucleic acid damage at higher doses ([Cl2] > 0.3 mg L(-1)). Above a threshold dose (between 1.5 and 3 mg Cl2 L(-1)), nucleic acids appeared severely damaged and incapable of being stained by PI or SYBR-II. These results constitute evidence that FCM is a promising tool for assessing drinking water bacteria injuries and for controlling chlorine disinfection efficiency much more rapidly than the standard sensitive but time-consuming heterotrophic plate count method. 相似文献
969.
Some studies of long term rice storage are presented. Swelling properties, consistency, gelatinisation and sensory properties are separately evaluated. 相似文献
970.
Many drugs used during resuscitations, are mighty oxidants able to induce intravascular hemolysis in patient with G6PD deficiency. Reversible and not immediately recurrent, hemolysis should be avoided by systematic (prevention) using specific blood tests. This paper was suggested by the case of a 37-year-old (Malgache) patient, with no history sustaining an acute hemolysis with kidney failure, appearing after intra-operative phenothiazine injection. 相似文献