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51.
目的:了解延边地区朝鲜族和汉族居民的脂肪分布特征及其与血压、血脂及血糖的关系。方法:于2006-08-8/17在延边地区九龙和翁声社区随机选择40~60岁朝鲜族和汉族常住居民2378名进行内脏脂肪率和体脂肪率以及血压、血脂、血糖等生化指标的检测。调查以健康体检形式进行,①内脏脂肪和体脂肪率测定采用日本TANITA株式会社生产的BC-600型体成分计测定,并且按其判定标准确定超过标准者[内脏脂肪率≥15%(男)、≥10%(女),体脂肪率(40~59岁)≥23%(男)、≥36%(女),体脂肪率(≥60岁)≥25%(男)、≥37%(女)]。②取清晨空腹(禁食12h)静脉血,采用日立-7600-010全自动生化分析仪测量血清总胆固醇、三酰甘油、高密度脂蛋白胆固醇、空腹血糖等指标。③高血压的诊断标准:收缩压≥140mmHg(1mmHg=0.133kPa)及或舒张压≥90mmHg。④血脂异常的诊断标准:总胆固醇≥5.72mmol/L,三酰甘油≥1.7mmol/L,高密度脂蛋白胆固醇<0.90mmol/L(男)、<1.0mmol/L(女)。⑤高血糖的诊断标准:空腹血糖≥6.1mmol/L。结果:①汉族男性的内脏脂肪率和体脂肪率均值分别为(10.51±3.66)%和(22.70±4.85)%,朝鲜族男性分别为(9.16±3.81)%和(20.28±5.02)%,汉族均高于朝鲜族(P<0.01);汉族女性的内脏脂肪率和体脂肪率分别为(6.22±2.27)%和(35.31±5.65)%,朝鲜族女性分别为(5.88±2.19)%和(34.00±5.72)%,汉族均高于朝鲜族(P<0.01)。②汉族男性的内脏脂肪率和体脂肪率超标率分别为12.1%和45.8%,朝鲜族男性分别为7.8%和28.6%,汉族均高于朝鲜族(P<0.05);汉族女性的内脏脂肪率和体脂肪率超标率分别为6.7%和47.9%,朝鲜族女性分别为3.8%和37.3%,汉族均高于朝鲜族(P<0.05)。③Logistic逐步回归分析结果表明,内脏脂肪率与民族、性别、年龄、高血压、高三酰甘油血症和高血糖有密切关系;体脂肪率与民族、性别、高血压、高三酰甘油血症、低高密度脂蛋白血症和高血糖有密切的关系。结论:①延边地区汉族居民内脏脂肪率和体脂肪率平均水平及其超标率明显高于朝鲜族。②内脏脂肪率和体脂肪率均与民族、性别、年龄(体脂肪率除外)、高血压、高三酰甘油血症和高血糖相关。 相似文献
52.
The Cobas TaqMan MTB test, based on real-time PCR technology, was evaluated for direct detection of Mycobacterium tuberculosis complex (MTBC) in respiratory specimens. A total of 1,093 samples from 446 patients, including 118 acid-fast smear-positive and 975 acid-fast smear-negative specimens, were investigated. Diagnostic cultures performed with 7H11 agar, Löwenstein-Jensen medium, and the Bactec MGIT 960 system were considered the reference methods. When discrepant results between the Cobas TaqMan MTB test and culture occurred, additional results from the BD MGIT TBc identification test and the GenoType Mycobacterium CM test performed on growth-positive and acid-fast-stain-positive MGIT tubes and review of the patient''s medical history were used for discrepancy analysis. The overall sensitivity, specificity, positive predictive value, and negative predictive value for the Cobas TaqMan MTB test were 91.5%, 98.7%, 91.5%, and 98.7%, respectively. In general, the performance of the new Cobas TaqMan MTB test was comparable to that of the replaced Cobas Amplicor MTB system. The most prominent feature of the new system was its extraordinarily high sensitivity (79.5%) for detecting MTBC in smear-negative specimens; out of 44 smear-negative but culture-positive specimens, 35 were positive by the new system. The Cobas TaqMan MTB assay, including DNA extraction, can be completed within 3 h. 相似文献
53.
54.
This study reports new N-isopropylacrylamide (NIPAM) polymer gel recipes with increased dose sensitivity and improved dose resolution for x-ray CT readout. NIPAM can be used to increase the solubility of N, N'-methylenebisacrylamide (Bis) in aqueous solutions from approximately 3% to 5.5% by weight, enabling the manufacture of dosimeters containing up to 19.5%T, which is the total concentration of NIPAM and Bis by weight. Gelatin is shown to have a mild influence on dose sensitivity when gels are imaged using x-ray CT, and a stronger influence when gels are imaged optically. Phantoms that contain only 3% gelatin and 5 mM tetrakis hydroxymethyl phosphonium chloride are sufficiently stiff for dosimetry applications. The best cosolvent-free gel formulation has a dose sensitivity in the linear range (~0.88 H Gy(-1)) that is a small improvement compared to the best NIPAM-based gels that incorporate isopropanol as a cosolvent (~0.80 H Gy(-1)). This new gel formulation results in enhanced dose resolution (~0.052 Gy) for x-ray CT readout, making clinical applications of this imaging modality more feasible. 相似文献
55.
Sheng‐Hsiung Yang Chun‐Hao Huang Chiu‐Hsiang Chen Chain‐Shu Hsu 《Macromolecular chemistry and physics.》2009,210(1):37-47
A new series of disubstituted polyacetylene derivatives that contain multi‐fluorine atoms on the pendent phenyl ring have been synthesized and characterized. The results reveal a greater red‐shift in UV‐vis absorption and PL emission upon incorporating more fluorine atoms on the pendent phenyl ring. Among them, disubstituted polyacetylene with a difluorophenyl group ( PDPA‐2F ) showed the highest luminescent efficiency. The device performance can be promoted by blending a hole‐transporting material TM‐TPD into PDPA‐2F as the active layer or by using a light‐emitting copolymer in which PDPA‐2F was copolymerized with a carbazole group ( PDPA‐2Fcab ). A light‐emitting diode of ITO/PEDOT/ PDPA‐2Fcab /Ca/Al revealed a maximum luminescence of 4230 cd · m?2 at 14 V and a maximum current efficiency of 3.37 cd · A?1 at 7 V.
56.
Hsun-Pi Su Seng-Kai Tung Lei-Ron Tseng Wen-Cherng Tsai Tung-Ching Chung Tsung Chain Chang 《Journal of clinical microbiology》2009,47(5):1386-1392
The genus Legionella contains a diverse group of motile, asaccharolytic, nutritionally fastidious gram-negative rods. Legionella pneumophila is the most important human pathogen, followed by L. micdadei, L. longbeachae, L. dumoffii, and other rare species. Accurate identification of Legionella spp. other than L. pneumophila is difficult because of biochemical inertness and phenotypic identity of different species. The feasibility of using an oligonucleotide array for identification of 18 species of Legionella was evaluated in this study. The method consisted of PCR amplification of the macrophage infectivity potentiator mip gene, followed by hybridization of the digoxigenin-labeled PCR products to a panel of 30 oligonucleotide probes (16- to 24-mers) immobilized on a nylon membrane. A collection of 144 target strains (strains we aimed to identify) and 50 nontarget strains (44 species) were analyzed by the array. Both test sensitivity (144/144 strains) and specificity (50/50 strains) of the array were 100%. The whole procedure for identification of Legionella species by the array can be finished within a working day, starting from isolated colonies. It was concluded that species identification of clinically relevant Legionella spp. by the array method is very reliable and can be used as an accurate alternative to conventional or other molecular methods for identification of Legionella spp.The genus Legionella currently contains 50 validly named species (http://www.dsmz.de/bactnom/bactname.htm), and among them, 20 have been found to be human pathogens (6, 10). Legionnaires'' disease (LD) is caused mainly by inhalation of aerosols generated from water sources contaminated with Legionella spp. (6, 40). While most species of Legionella are normal environmental flora, many are implicated in opportunistic infections in immunocompromised patients (14). Pulmonary infections caused by Legionella may be subclinical or severe (27), and the fatality rate can approach 50% in immunocompromised patients (49).Legionella pneumophila accounts for about 85 to 90% of cases of LD (6, 26, 49). Other Legionella spp. implicated in human infections include L. micdadei, L. longbeachae, L. dumoffii, and some less encountered species, such as L. anisa, L. bozemanae, L. feeleii, and L. wadsworthii (49). L. pneumophila is normally identified by immunofluorescent-antibody assay. A specific FDA-cleared fluorescein isothiocyanate-labeled monoclonal antibody (Bio-Rad, Hercules, CA) for all serogroups of L. pneumophila and fluorescein isothiocyanate-labeled polyclonal antisera specific for L. pneumophila serogroup 1 (m-TECH, Atlanta, GA) are commercially available (6). Accurate identification of Legionella spp. other than L. pneumophila and L. pneumophila serogroup 1 can be quite difficult due to serological cross-reactivities between serogroups and species, biochemical inertness, and phenotypic identity of different species (6). Legionella isolates which fail to react with L. pneumophila antibodies are recommended to be identified by public health or reference laboratories (6). Antigen detection in urine specimens is also commonly used in hospitals for diagnosing infection caused by L. pneumophila (46).Molecular approaches have been developed to provide more rapid and accurate identification of Legionella spp. These methods include PCR (20, 25, 34), gene probe hybridization (24, 41), restriction fragment length polymorphism analysis (21, 38), and sequence analysis of the rRNA gene (47) and the macrophage infectivity potentiator gene mip (35, 41). Since diagnostic delay may result in increased mortality for patients with LD (15), real-time PCR assay has been a focus of many studies in recent years (5, 13, 14, 17, 19, 34, 36, 41, 48). However, with real-time PCR assay, only L. pneumophila and a very limited number of Legionella spp. can be detected or identified.Recently, DNA array technology has been applied to identify a wide variety of bacteria that are difficult to be differentiated by phenotypic traits or whose identification may take a long time (12, 31, 43). This study aimed to develop an oligonucleotide array based on mip gene sequences to identify 18 species of Legionella that have been found to cause human infections in the literature (10). 相似文献
57.
Nitrosopumilus maritimus genome reveals unique mechanisms for nitrification and autotrophy in globally distributed marine crenarchaea 总被引:1,自引:0,他引:1
C. B. Walker J. R. de la Torre M. G. Klotz H. Urakawa N. Pinel D. J. Arp C. Brochier-Armanet P. S. G. Chain P. P. Chan A. Gollabgir J. Hemp M. Hügler E. A. Karr M. K?nneke M. Shin T. J. Lawton T. Lowe W. Martens-Habbena L. A. Sayavedra-Soto D. Lang S. M. Sievert A. C. Rosenzweig G. Manning D. A. Stahl 《Proceedings of the National Academy of Sciences of the United States of America》2010,107(19):8818-8823
58.
Dendritic cells (DCs) are key antigen-presenting cells (APCs), which link innate and adaptive immunity, ultimately activating antigen-specific T cells. This review examines the relationship between the acute and chronic myeloid leukaemias and cells with DC properties. DCs are non-dividing terminally differentiated cells, and ex vivo leukaemic cells or cell lines show little similarity to DCs. However, many leukaemias differentiate further in response to defined stimuli, and retain a degree of lineage plasticity. Therefore, several studies have explored the response of leukaemic cells to the in vitro regimens used to differentiate ex vivo primary DCs. Recent data suggest that the most 'dendritic-like' cells can be derived from more undifferentiated myeloid leukaemias, such as the myelomonocytic Mutz-3 cell line. These findings have important implications for understanding the developmental origins of DCs, for harnessing the APC properties of this class of tumour to stimulate the therapeutic anti-tumour immunity, and for developing useful models for the study of human DC physiology and pathology. There is a strong rationale for further exploration of this class of tumour and its relationship to the normal DC. 相似文献
59.
60.
冠状动脉搭桥术早期并发症及死亡率(附196例报告) 总被引:1,自引:0,他引:1
1985年1月~1987年12月作者于荷兰格罗宁根医学科学院心胸外科主做了196例冠状动脉搭桥术。术后早期死亡2例(1.0%)、内出血3例(1.5%)、胸骨裂开2例(1.0%)、心律紊乱40例(20.4%)、围手术期心肌梗塞5例(2.6%),本文就术后早期并发症进行了讨论。 相似文献