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961.
Lai SW Li TC Lin CC Tan CK Ng KC Lai MM Liu CS 《The Yale journal of biology and medicine》2001,74(2):89-94
BACKGROUND: Our study used data collected in Chung-Hsing Village in May 1998 to evaluate the prevalence of hypertension and its correlates in Taiwanese elderly people. METHODS: All of individuals aged 65 and over were recruited as study subjects. A total of 1,093 persons, out of 1,774 registered residents, were contacted by face-to-face interview The response rate was 61.6 percent. However, only 586 respondents had blood tests and completed questionnaires. Analysis in this study was based on these 586 subjects. In order to study the significant correlates of hypertension, the t-test, chi-square analysis, and multivariate logistic regression were used. RESULTS: Our results showed that 66 percent were men and 34 percent were women. The mean age was 73.1 +/- 5.3 years. The proportions of hypertension were 53.09 percent in men and 56.06 percent in women (p > 0.05). After controlling the other covariates, the multivariate logistic regression analysis showed that the significant related factors of hypertension were obesity (OR = 1.88, 95 percent CI = 1.06-3.34, p < 0.05) and renalfunction impairment (OR = 1.69, 95 percent CI = 1.02-2.80, p < 0.05). CONCLUSIONS: The prevalence of hypertension was high in elderly people. Hypertension is significantly associated with obesity and renalfunction impairment in elderly people. 相似文献
962.
Water table management reduces tile nitrate loss in continuous corn and in a soybean-corn rotation 总被引:1,自引:0,他引:1
Drury CF Tan CS Gaynor JD Reynolds WD Welacky TW Oloya TO 《TheScientificWorldJournal》2001,1(Z2):163-169
Water table management systems can be designed to alleviate soil water excesses and deficits, as well as reduce nitrate leaching losses in tile discharge. With this in mind, a standard tile drainage (DR) system was compared over 8 years (1991 to 1999) to a controlled tile drainage/subirrigation (CDS) system on a low-slope (0.05 to 0.1%) Brookston clay loam soil (Typic Argiaquoll) in southwestern Ontario, Canada. In the CDS system, tile discharge was controlled to prevent excessive drainage, and water was pumped back up the tile lines (subirrigation) to replenish the crop root zone during water deficit periods. In the first phase of the study (1991 to 1994), continuous corn (Zea mays, L.) was grown with annual nitrogen (N) fertilizer inputs as per local soil test recommendations. In the second phase (1995 to 1999), a soybean (Glycine max L., Merr.)-corn rotation was used with N fertilizer added only during the two corn years. In Phase 1 when continuous corn was grown, CDS reduced total tile discharge by 26% and total nitrate loss in tile discharge by 55%, compared to DR. In addition, the 4-year flow weighted mean (FWM) nitrate concentration in tile discharge exceeded the Canadian drinking water guideline (10 mg N l(-1)) under DR (11.4 mg N l(-1)), but not under CDS (7.0 mg N l(-1)). In Phase 2 during the soybean-corn rotation, CDS reduced total tile discharge by 38% and total nitrate loss in tile discharge by 66%, relative to DR. The 4-year FWM nitrate concentration during Phase 2 in tile discharge was below the drinking water guideline for both DR (7.3 mg N l(-1)) and CDS (4.0 mg N l(-1)). During both phases of the experiment, the CDS treatment caused only minor increases in nitrate loss in surface runoff relative to DR. Hence CDS decreased FWM nitrate concentrations, total drainage water loss, and total nitrate loss in tile discharge relative to DR. In addition, soybean-corn rotation reduced FWM nitrate concentrations and total nitrate loss in tile discharge relative to continuous corn. CDS and crop rotations with reduced N fertilizer inputs can thus improve the quality of tile discharge water substantially. 相似文献
963.
Letavic MA Axt MZ Barberia JT Carty TJ Danley DE Geoghegan KF Halim NS Hoth LR Kamath AV Laird ER Lopresti-Morrow LL McClure KF Mitchell PG Natarajan V Noe MC Pandit J Reeves L Schulte GK Snow SL Sweeney FJ Tan DH Yu CH 《Bioorganic & medicinal chemistry letters》2002,12(10):1387-1390
A series of novel, selective TNF-alpha converting enzyme inhibitors based on 4-hydroxy and 5-hydroxy pipecolate hydroxamic acid scaffolds is described. The potency and selectivity of TACE inhibition is dramatically influenced by the nature of the sulfonamide group which interacts with the S1' site of the enzyme. Substituted 4-benzyloxybenzenesulfonamides exhibit excellent TACE potency with >100x selectivity over inhibition of matrix metalloprotease-1 (MMP-1). Alkyl substituents on the ortho position of the benzyl ether moiety give the most potent inhibition of TNF-alpha release in LPS-treated human whole blood. 相似文献
964.
Tan P Mitchell DA Buss TN Holmes MA Anasetti C Foote J 《Journal of immunology (Baltimore, Md. : 1950)》2002,169(2):1119-1125
Humanized Abs are created by combining, at the genetic level, the complementarity-determining regions of a murine mAb with the framework sequences of a human Ab variable domain. This leads to a functional Ab with reduced immunogenic side effects in human therapy. In this study, we report a new approach to humanizing murine mAbs that may reduce immunogenicity even further. This method is applied to humanize the murine anti-human CD28 Ab, 9.3. The canonical structures of the hypervariable loops of murine 9.3 were matched to human genomic V gene sequences whose hypervariable loops had identical or similar canonical structures. Framework sequences for those human V genes were then used, unmodified, with the 9.3 complementarity-determining regions to construct a humanized version of 9.3. The humanized 9.3 and a chimeric 9.3 control were expressed in Escherichia coli as Fab. The humanized Fab showed a moderate loss in avidity in a direct binding ELISA with immobilized CD28-Ig fusion protein (CD28-Ig). Humanized 9.3 blocked ligation of CD28-Ig to cells expressing the CD28 receptor CD80. Lastly, the humanized 9.3 showed biological activity as an immunosuppressant by inhibiting a MLR. 相似文献
965.
966.
967.
Akbar Ali M Mirza AH Butcher RJ Tarafder MT Keat TB Ali AM 《Journal of inorganic biochemistry》2002,92(3-4):141-148
Palladium(II) and platinum(II) complexes of general empirical formula, [M(NS)(2)] (NS=uninegatively charged acetone Schiff bases of S-methyl- and S-benzyldithiocarbazate; M=Pt(II) and Pd(II)) have been prepared and characterized by a variety of physicochemical techniques. Based on conductance, IR and electronic spectral evidence, a square-planar structure is assigned to these complexes. The crystal and molecular structure of the [Pd(asme)(2)] complex (asme=anionic form of the acetone Schiff base of S-methyldithiocarbazate) has been determined by X-ray diffraction. The complex has a distorted cis-square planar structure with the ligands coordinated to the palladium(II) ions as uninegatively charged bidentate NS chelating agents via the azomethine nitrogen and the mercaptide sulfur atoms. The distortion from a regular square-planar geometry is attributed to the restricted bite angles of the ligands. Antimicrobial tests indicate that the Schiff bases exhibit strong activities against the pathogenic bacteria, Bacillus subtilis (mutant defective DNA repair), methicillin-resistant Staphylococcus aureus, B. subtilis (wild type) and Pseudomonas aeruginosa and the fungi, Candida albicans (CA), Candida lypotica (2075), Saccharomyces cerevisiae (20341) and Aspergillus ochraceous (398)-the activities exhibited by these compounds being greater than that of the standard antibacterial and antifungal drugs, streptomycin and nystatin, respectively. The palladium(II) and platinum(II) complexes are inactive against most of these organisms but, the microbe, Pseudomonas aeruginosa shows strong sensitivity to the platinum(II) complexes. Screening of the compounds for their cytotoxicities against T-lymphoblastic leukemia cancer cells has shown that the acetone Schiff base of S-methyldithiocarbazate (Hasme) exhibits a very weak activity, whereas the S-benzyl derivative (Hasbz) is inactive. However, the palladium(II) complexes exhibit strong cytotoxicities against this cancer; their activities being more than that of the standard anticancer drug, tamoxifen. The [Pt(asme)(2)] complex exhibits a very weak cytotoxicity, whereas [Pt(asbz)(2)] is inactive against leukemic cells. 相似文献
968.
969.
970.
Genetic algorithms applied to multi-class prediction for the analysis of gene expression data 总被引:9,自引:0,他引:9
MOTIVATION: An important challenge in the use of large-scale gene expression data for biological classification occurs when the expression dataset being analyzed involves multiple classes. Key issues that need to be addressed under such circumstances are the efficient selection of good predictive gene groups from datasets that are inherently 'noisy', and the development of new methodologies that can enhance the successful classification of these complex datasets. METHODS: We have applied genetic algorithms (GAs) to the problem of multi-class prediction. A GA-based gene selection scheme is described that automatically determines the members of a predictive gene group, as well as the optimal group size, that maximizes classification success using a maximum likelihood (MLHD) classification method. RESULTS: The GA/MLHD-based approach achieves higher classification accuracies than other published predictive methods on the same multi-class test dataset. It also permits substantial feature reduction in classifier genesets without compromising predictive accuracy. We propose that GA-based algorithms may represent a powerful new tool in the analysis and exploration of complex multi-class gene expression data. AVAILABILITY: Supplementary information, data sets and source codes are available at http://www.omniarray.com/bioinformatics/GA. 相似文献