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991.
臂踝脉搏波传播速度(brachial-ankle pulse wave velocity,baPWV)测量是一种便捷、无创的方法,可用于人体动脉硬化度的评估,在临床和科学研究中广泛应用于血管早期病变的筛查和心血管系统风险的评估。本文设计开发了人体上臂和踝部脉搏波波形采集系统,并利用该系统对59名健康成年人进行实验,研究了目前三种最常用的脉搏波时标(pulse timing mark,PTM)定义方法对baPWV测量的影响。实验结果表明,选用不同的PTM方法所测得的baPWV结果具有显著的差异性(P0.001)。而且,PTM方法的不同还影响到了baPWV与年龄、血压的相互关系。 相似文献
992.
香青兰(Dracocephalum MoldavicaL.)为传统维吾尔族药材,具有补益心脑之功效,现代研究表明其对冠心病、心绞痛等病具有治疗作用。该文作者采用大鼠离体胸主动脉灌流技术,观察了香青兰总黄酮的血管舒张作用,旨在为阐明其活性物质基础和作用机制提供依据。结果表明:1)10.0~40.0mg/L香青兰总黄酮对内皮完整和去内皮大鼠主动脉环的基础张力没有明显影响。2)10.0~40.0mg/L香青兰总黄酮对去甲肾上腺素(NE,10μmol/L)所致的内皮完整和去内皮血管均有浓度依赖性的舒张作用,对内皮完整血管的舒张作用更强;一氧化氮合酶抑制剂左旋硝基精氨酸甲酯L-NAME(0.1mmol/L)、鸟苷酸环化酶抑制剂亚甲蓝(10μmol/L)和环氧合酶抑制剂吲哚美辛(10μmol/L)预处理均可一定程度上抑制香青兰总黄酮的血管舒张作用,表明血管内皮合成的一氧化氮(NO)信号通路和前列环素(PGI2)信号通路参与了香青兰总黄酮的血管舒张作用。3)香青兰总黄酮预处理去内皮血管环可以抑制细胞外钙内流所致的血管收缩,但对细胞内钙释放所致的血管收缩没有影响,香青兰总黄酮对高钾(60mmol/L KCl)所致血管收缩没有... 相似文献
993.
基于景观生态的城市土地开发适宜性评价——以丹东市为例 总被引:7,自引:0,他引:7
城市土地开发适宜性评价是城市总体规划中的一项重要基础性工作,其核心是合理分配利用有限的土地资源。在进行耕地适宜性评价和建设用地适宜性评价的基础上,针对丹东市不同的发展目标,提出3个城市土地开发适宜性评价方案,包括经济发展优先方案、生态保护优先方案以及协调发展方案,并按照3个方案对丹东市进行城市土地开发适宜性评价。通过选择适当指标,构建了由景观稳定度和景观干扰度组成的景观生态质量评价体系,并对3个适宜性方案进行对比与优选。结果表明,丹东市按照经济发展优先的城市土地开发适宜性方案进行开发,则景观干扰程度最高,景观稳定程度最低,景观生态质量最低;按照生态保护优先方案进行开发,则景观干扰程度居中,景观稳定程度最高,而景观生态质量居中;按照协调发展方案进行开发,则景观干扰程度最低,景观稳定程度居中,并且具有最高的景观生态质量。通过综合比较,应选择协调发展方案作为丹东市城市建设空间布局的首选方案。 相似文献
994.
Nadia Hanum Valentina Cambiano Janey Sewell Alison J. Rodger Nneka Nwokolo David Asboe Richard Gilson Amanda Clarke Ada R. Miltz Simon Collins Valerie Delpech Sara Croxford Andrew N. Phillips Fiona C. Lampe for the AURAH Study Group 《PLoS medicine》2021,18(6)
BackgroundProspective cohort studies of incident HIV and associated factors among gay, bisexual, and other men who have sex with men (GBMSM) in the United Kingdom are lacking. We report time trends in and factors associated with HIV incidence between 2013 and 2019 among a cohort of GBMSM: the AURAH2 prospective study.Methods and findingsParticipants were recruited through 1 of 3 sexual health clinics in London and Brighton (July 2013 to April 2016) and self-completed a baseline paper questionnaire and subsequent 4-monthly and annual online questionnaires (March 2015 to March 2018), including information on sociodemographics, lifestyle, health and well-being, HIV status, sexual/HIV-related behaviours, and preexposure prophylaxis and postexposure prophylaxis (PrEP/PEP). Incident HIV was ascertained by linkage with national HIV surveillance data from Public Health England (PHE). We investigated the associations of HIV incidence with (1) baseline factors using mixed-effects Weibull proportional hazard models, unadjusted and adjusted for age, country of birth and ethnicity, sexuality, and education level; and (2) time-updated factors, using mixed-effects Poisson regression models.In total, 1,162 men (mean age 34 years, 82% white, 94% gay, 74% university-educated) were enrolled in the study. Thirty-three HIV seroconversions occurred over 4,618.9 person-years (PY) of follow-up: an overall HIV incidence rate (IR) of 0.71 (95% confidence interval (CI) 0.51 to 1.00) per 100 PY. Incidence declined from 1.47 (95% CI 0.48 to 4.57) per 100 PY in 2013/2014 to 0.25 (95% CI 0.08 to 0.78) per 100 PY in 2018/2019; average annual decline was 0.85-fold (p < 0.001). Baseline factors associated with HIV acquisition included the following: injection drug use (6/38 men who reported injection drug-acquired HIV; unadjusted conditional hazard ratio (HR) 27.96, 95% CI 6.99 to 111.85, p < 0.001), noninjection chemsex-related drug use (13/321; HR 6.45, 95% CI 1.84 to 22.64, p < 0.001), condomless anal sex (CLS) (26/741; HR 3.75, 95% CI 1.31 to 10·74, p = 0.014); higher number of CLS partners (HRs >10 partners [7/57]; 5 to 10 partners [5/60]; and 2 to 4 partners [11/293]: 14.04, 95% CI 4.11 to 47.98; 9.60, 95% CI 2.58 to 35.76; and 4.05, 95% CI 1.29 to 12.72, respectively, p < 0.001); CLS with HIV–positive partners (14/147; HR 6.45, 95% CI 3.15 to 13.22, p < 0.001), versatile CLS role (21/362; HR 6.35, 95% CI 2.18 to 18.51, p < 0.001), group sex (64/500; HR 8.81, 95% CI 3.07 to 25.24, p < 0.001), sex for drugs/money (4/55, HR 3.27, 95% CI 1.14 to 9.38, p = 0.027) (all in previous 3 months); previous 12-month report of a bacterial sexually transmitted infection (STI) diagnoses (21/440; HR 3.95, 95% CI 1.81 to 8.63, p < 0.001), and more than 10 new sexual partners (21/471, HRs 11 to 49, 50 to 99, and >100 new partners: 3.17, 95% CI 1.39 to 7.26; 4.40, 95% CI 1.35 to 14.29; and 4.84, 95% CI 1.05 to 22.4, respectively, p < 0.001). Results were broadly consistent for time-updated analysis (n = 622 men). The study’s main limitation is that men may not be representative of the broader GBMSM population in England.ConclusionsWe observed a substantial decline in HIV incidence from 2013 to 2019 among GBMSM attending sexual health clinics. Injection drug use, chemsex use, and measures of high-risk sexual behaviour were strongly associated with incident HIV. Progress towards zero new infections could be achieved if combination HIV prevention including Test and Treat strategies and routine commissioning of a PrEP programme continues across the UK and reaches all at-risk populations.Nadia Hanum and colleagues analyze trends in HIV incidence among gay, bisexual, and other Men Who Have Sex with Men attending sexual health clinics in England. 相似文献
995.
Sasisopin Kiertiburanakul Romanee Chaiwarith Sunee Sirivichayakul Rossana Ditangco Awachana Jiamsakul Patrick C. K. Li Pacharee Kantipong Christopher Lee Winai Ratanasuwan Adeeba Kamarulzaman Annette H. Sohn Somnuek Sungkanuparph for the TREAT Asia Studies to Evaluate Resistance Surveillance Monitoring Studies 《PloS one》2013,8(6)
996.
Kaysia T. Ludford Panagiotis Vagenas Javier R. Lama Jesus Peinado Pedro Gonzales Rene Leiva Monica Pun Jorge Sanchez Frederick L. Altice for the Peruvian HIV Sentinel Surveillance Working Group 《PloS one》2013,8(8)
Background
Peru''s HIV epidemic is concentrated among men who have sex with men (MSM). The contribution of alcohol use disorders (AUDs) to known high-risk behaviors associated with HIV transmission in this context has not been well characterized.Methods
Between June and October 2011, 5,148 sexually active MSM were recruited using convenience sampling in five cities to participate in a cross-sectional bio-behavioral survey. Five high-risk sexual criteria previously associated with incident HIV infection in this setting were selected a priori as the dependent outcomes. Screening for AUDs used the validated Alcohol Use Disorders Identification Test (AUDIT) and AUDS were stratified by severity. Unadjusted and adjusted odds ratios (AOR) were computed to establish the independent correlates of the five dependent outcomes.Results
The majority (62.8%) of participants met screening criteria for having an AUD, which were independently correlated with each of the following high-risk sexual risk behaviors in the previous 6 months: 1) >5 sexual partners [AOR = 1.76; (1.54–2.02)]; 2) sex with an HIV-infected partner [AOR = 1.29; (1.03–1.62)]; 3) having a sexually transmitted infection [AOR = 1.38; (1.13–1.68)]; 4) being a sex worker [AOR = 1.61; (1.40–1.87)]; and 5) unprotected sex during last encounter [AOR = 1.22; (1.09–1.38)]. Recent drug use was also correlated with having >5 sexual partners [AOR = 1.42 (1.19–1.71)], sex work [AOR = 1.97 (1.63–2.39)] and unprotected sex during last encounter [AOR = 1.31 (1.11–1.54)]. For each dependent variable, the association with AUDs significantly increased with increasing AUD severity.Conclusions
AUDs are highly prevalent among MSM in Peru and are associated with increased HIV risk-taking behaviors that are associated with HIV transmission. Strategies that target problematic drinking such as medication-assisted therapy, behavioral counseling and structural interventions could potentially reduce risky behaviors and ultimately reduce HIV transmission among MSM in Peru. 相似文献997.
Chuey Yan Lee Noran N. Hairi Wan Azman Wan Ahmad Omar Ismail Houng Bang Liew Robaayah Zambahari Rosli Mohd Ali Alan Yean Yip Fong Kui Hian Sim for the NCVD-PCI Investigators 《PloS one》2013,8(8)
Objectives
To assess whether gender differences exist in the clinical presentation, angiographic severity, management and outcomes in patients with coronary artery disease (CAD).Methods
The study comprised of 1,961 women and 8,593 men who underwent percutaneous coronary intervention (PCI) and were included in the Malaysian NCVD-PCI Registry from 2007–2009. Significant stenosis was defined as ≥70% stenosis in at least one of the epicardial vessels.Results
Women were significantly older and had significantly higher rates of diabetes mellitus, hypertension, chronic renal failure, new onset angina and prior history of heart failure whereas smokers and past history of myocardial infarction were higher in men. In the ST-elevation myocardial infarction (STEMI) cohort, more women were in Killip class III-IV, had longer door-to-balloon time (169.5 min. vs 127.3 min, p<0.052) and significantly longer transfer time (300.4 min vs 166.3 min, p<0.039). Overall, women had significantly more left main stem (LMS) disease (1.3% vs 0.6%, p<0.003) and smaller diameter vessels (<3.0 mm: 45.5% vs 34.8%, p<0.001). In-hospital mortality rates for all PCI, STEMI, Non-STEMI (NSTEMI) and unstable angina for women and men were 1.99% vs 0.98%, Odds ratio (OR): 2.06 (95% confidence interval (CI): 1.40 to 3.01), 6.19% vs 2.88%, OR: 2.23 (95% CI: 1.31 to 3.79), 2.90% vs 0.79%, OR: 3.75 (95% CI: 1.58 to 8.90) and 1.79% vs 0.29%, OR: 6.18 (95% CI: 0.56 to 68.83), respectively. Six-month adjusted OR for mortality for all PCI, STEMI and NSTEMI in women were 2.18 (95% CI: 0.97 to 4.90), 2.68 (95% CI: 0.37 to 19.61) and 2.66 (95% CI: 0.73 to 9.69), respectively.Conclusions
Women who underwent PCI were older with more co-morbidities. In-hospital and six-month mortality for all PCI, STEMI and NSTEMI were higher due largely to significantly more LMS disease, smaller diameter vessels, longer door-to-balloon and transfer time in women. 相似文献998.
Chia-Jung Chang Ho-Chang Kuo Jeng-Sheng Chang Jong-Keuk Lee Fuu-Jen Tsai Chiea Chuen Khor Li-Ching Chang Shih-Ping Chen Tai-Ming Ko Yi-Min Liu Ying-Ju Chen Young Mi Hong Gi Young Jang Martin L. Hibberd Taco Kuijpers David Burgner Michael Levin Jane C. Burns Sonia Davila International Kawasaki Disease Genetics Consortium? Korean Kawasaki Disease Genetics Consortium? Taiwan Kawasaki Disease Genetics Consortium? Yuan-Tsong Chen Chien-Hsiun Chen Jer-Yuarn Wu Yi-Ching Lee 《PloS one》2013,8(8)
The BLK and CD40 loci have been associated with Kawasaki disease (KD) in two genome-wide association studies (GWAS) conducted in a Taiwanese population of Han Chinese ancestry (Taiwanese) and in Japanese cohorts. Here we build on these findings with replication studies of the BLK and CD40 loci in populations of Korean and European descent. The BLK region was significantly associated with KD susceptibility in both populations. Within the BLK gene the rs2736340-located linkage disequilibrium (LD ) comprising the promoter and first intron was strongly associated with KD, with the combined results of Asian studies including Taiwanese, Japanese, and Korean populations (2,539 KD patients and 7,021 controls) providing very compelling evidence of association (rs2736340, OR = 1.498, 1.354–1.657; P = 4.74×10−31). We determined the percentage of B cells present in the peripheral blood mononuclear cell (PBMC) population and the expression of BLK in the peripheral blood leukocytes (leukocytes) of KD patients during the acute and convalescent stages. The percentage of B cells in the PBMC population and the expression of BLK in leukocytes were induced in patients in the acute stage of KD. In B cell lines derived from KD patients, and in purified B cells from KD patients obtained during the acute stage, those with the risk allele of rs2736340 expressed significantly lower levels of BLK. These results suggest that peripheral B cells play a pathogenic role during the acute stage of KD. Decreased BLK expression in peripheral blood B cells may alter B cell function and predispose individuals to KD. These associative data suggest a role for B cells during acute KD. Understanding the functional implications may facilitate the development of B cell-mediated therapy for KD. 相似文献
999.
Bixia Gao Luxia Zhang Haiyan Wang the China National Survey of Chronic Kidney Disease Working Group 《PloS one》2013,8(6)
Background
Previous studies indicated that lifestyle-related cardiovascular risk factors tend to be clustered in certain individuals. However, population-based studies, especially from developing countries with substantial economic heterogeneity, are extremely limited. Our study provides updated data on the clustering of cardiovascular risk factors, as well as the impact of lifestyle on those factors in China.Methods
A representative sample of adult population in China was obtained using a multistage, stratified sampling method. We investigated the clustering of four cardiovascular disease (CVD) risk factors (defined as two or more of the following: hypertension, diabetes, dyslipidemia and overweight) and their association with unhealthy lifestyles (habitual drinking, physical inactivity, chronic use of non-steroidal anti-inflammatory drugs (NSAIDs) and a low modified Dietary Approaches to Stop Hypertension (DASH) score).Results
Among the 46,683 participants enrolled in this study, only 31.1% were free of any pre-defined CVD risk factor. A total of 20,292 subjects had clustering of CVD risk factors, and 83.5% of them were younger than 65 years old. The adjusted prevalence of CVD risk factor clustering was 36.2%, and the prevalence was higher among males than among females (37.9% vs. 34.5%). Habitual drinking, physical inactivity, and chronic use of NSAIDs were positively associated with the clustering of CVD risk factors, with ORs of 1.60 (95% confidence interval [CI] 1.40 to1.85), 1.20 (95%CI 1.11 to 1.30) and 2.17 (95%CI 1.84 to 2.55), respectively. The modified DASH score was inversely associated with the clustering of CVD risk factors, with an OR of 0.73 (95%CI 0.67 to 0.78) for those with modified DASH scores in the top tertile. The lifestyle risk factors were more prominent among participants with low socioeconomic status.Conclusion
Clustering of CVD risk factors was common in China. Lifestyle modification might be an effective strategy to control CVD risk factors. 相似文献1000.
Hanna Leicht Hans-Helmut K?nig Nina Stuhldreher Cadja Bachmann Horst Bickel Angela Fuchs Kathrin Heser Frank Jessen Mirjam K?hler Melanie Luppa Edelgard M?sch Michael Pentzek Steffi Riedel-Heller Martin Scherer Jochen Werle Siegfried Weyerer Birgitt Wiese Wolfgang Maier for the AgeCoDe study group 《PloS one》2013,8(7)