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81.
血管紧张素转换酶基因多态性与高血压微量蛋白尿的关系   总被引:1,自引:1,他引:1  
为研究血管紧张素转换酶基因插入/缺失(I/D)多态性与高血压微量蛋白尿的关系。应用聚合酶链反应方法扩增50例正常人,50例高血压伴有微量蛋白尿患者和49例高血压不伴有微量蛋白尿患者的白细胞血管紧张素转换酶基因上287bp片段,根据插入(Ⅰ)或/缺失(D)来判断其多态性,用放射免疫法测定所有对象的尿微量白蛋白。结果发现,微量蛋白尿组与健康对照组相比,其D等位基因及DD基因型显著升高。微量蛋白尿组与单纯高血压组相比,其D等位基因及DD基因型显著程式高。单纯高血压组与健康对照组相比,血管紧张素转换酶基因型和等位基因频率无显著性差异。以上提示,血压紧张素转换酶基因多态性与高血压微量蛋白尿有关联性,DD基因型可能与高血压早期肾脏损害有关。  相似文献   
82.
This paper presents for the first time a p-type 4H silicon carbide (4H-SiC) van der Pauw strain sensor by utilizing the strain induced effect in four-terminal devices. The sensor was fabricated from a 4H-SiC (0001) wafer, using a 1 μm thick p-type epilayer with a concentration of 1018 cm−3. Taking advantage of the four-terminal configuration, the sensor can eliminate the need for resistance-to-voltage conversion which is typically required for two-terminal devices. The van der Pauw sensor also exhibits an excellent repeatability and linearity with a significantly large output voltage in induced strain ranging from 0 to 334 ppm. Various sensors aligned in different orientations were measured and a high sensitivity of 26.3 ppm−1 was obtained. Combining these performances with the excellent mechanical strength, electrical conductivity, thermal stability, and chemical inertness of 4H-SiC, the proposed sensor is promising for strain monitoring in harsh environments.

This paper presents for the first time a p-type 4H silicon carbide (4H-SiC) van der Pauw strain sensor by utilizing the strain induced effect in four-terminal devices.  相似文献   
83.
We present the immunoassay of tau proteins (total tau and phosphorylated tau) in human sera using surface plasmon resonance (SPR) fiber sensors. This assay aimed at harvesting the advantages of using both SPR fiber sensors and a blood-based assay to demonstrate label-free point-of-care-testing (POCT) patient-friendly assay in a compact format for the early diagnosis of Alzheimer''s disease (AD). For conducting the assay, we used human sera of 40 subjects divided into halves, which were grouped into AD patients and control groups according to a number of neuropsychological tests. We found that on an average, the concentrations of both total tau and phosphorylated tau proteins (all known to be higher in cerebrospinal fluid (CSF) and the brain) turned out to be higher in human sera of AD patients than in controls. The limits of detection of total tau and phosphorylated tau proteins were 2.4 pg mL−1 and 1.6 pg mL−1, respectively. In particular, it was found that the AD group exhibited average concentration of total tau proteins 6-fold higher than the control group, while concentration of phosphorylated tau proteins was 3-fold higher than that of the control. We can attribute this inhomogeneity between both types of tau proteins (in terms of increase of control-to-AD in average concentration) to un-phosphorylated tau proteins being more likely to be produced in blood than phosphorylated tau proteins, which possibly is one of the potential key elements playing an important role in AD progress.

Blood-based early diagnosis of Alzheimer''s disease using a plasmonic fiber sensor that detects immunoreaction of tau proteins.  相似文献   
84.
Viral hepatitis infection is a major global issue and a leading cause of liver disease and associated deaths. Over time, patients infected with hepatitis B (HBV) or C virus (HCV) develop cirrhosis and, eventually, hepatocellular carcinoma (HCC). For this reason, they need to be constantly monitored. Current Asian guidelines recommend the determination of serum alpha-fetoprotein (AFP) together with liver ultrasounds every six months to detect HCC nodules. However, both methods have several limitations, and other biomarkers have been studied for monitoring cirrhosis, including SCCA-IgM, an immune-complex formed by Squamous Cell Carcinoma Antigen and IgM. To date, SCCA-IgM has been validated as a novel biomarker for liver diseases only in European populations. The aim of our study was to analyze SCCA-IgM as a biomarker to monitor cirrhosis evolution in an Asian cohort of patients and to compare its performance to that of AFP. We analyzed the concentration of AFP and SCCA-IgM in serum samples obtained from a group of Asian adult patients with cirrhosis or HCC and a control group of patients admitted for gastrointestinal disorders. In untreated patients and similarly to AFP, SCCA-IgM levels were significantly higher in patients with cirrhosis compared to those with HCC. In addition, SCCA-IgM, but not AFP serological levels, were significantly lower in HCC patients who were treated with surgical resection compared to those who received a different therapy.  相似文献   
85.
In Vietnam, a pilot ‘smoke-free hospital’ model was implemented in nine hospitals in 2009–2010 to supply lessons learned that would facilitate a replication of this model elsewhere. This study aimed to assess smoking patterns among health professionals and to detect levels of second-hand smoke (SHS) exposure within hospital premises before and after the ‘smoke-free hospital’ model implementation. A pre- and post-intervention cross-sectional study was conducted in nine purposively selected hospitals. Air nicotine levels were measured using passive nicotine monitors; smoking evidence was collected through on-site observations; and smoking patterns were assessed through interviews with health workers. Despite the ‘smoke-free hospital’ intervention, smoking continued among health-care workers who were former smokers. Specifically, self-reported smoking prevalence significantly decreased post-intervention, but the number of daily cigarettes smoked at workplaces among male health workers remained unchanged. Post-intervention, smoking was more likely to take place outside buildings and cafeterias. However, air nicotine levels in the doctors' lounges and in emergency departments did not change post-intervention. Air nicotine levels at other sites decreased minimally. Tailored tobacco cessation programmes, targeting current smokers and mechanisms to enforce non-smoking, should be established to meet requirements of Vietnam's comprehensive National Tobacco Control Law effective in May 2013.  相似文献   
86.
Using the Attitude-Skills-Knowledge (ASK) model, this study examined the prevalence of, and factors associated with, human immunodeficiency virus (HIV) testing among male motorbike taxi drivers (MMTDs). In a cross-sectional design, using quantitative approaches, 291 MMTDs were recruited from 135 sites across 13 districts in Hanoi, Vietnam, for a face-to-face interview. Applying the ASK model modified as a central theory, logistic regression was used to identify determinants of HIV testing. Although many MMTDs engaged in multiple risk behaviours for HIV, only 20.6% had been tested for HIV during the past 12 months. The tested model included one factor of the ASK model, HIV prevention knowledge (adjusted odds ratio [AOR] = 4.76; 95% confidence interval [CI] = 2.12–10.7) and five additional factors: being married (AOR = 3.13; 95% CI = 1.25–4.78), preferring sex with men or with both men and women (AOR = 8.72; 95% CI = 1.48–51.5), having lower number of lifetime sex partners (AOR = 0.66; 95% CI = 0.49–0.88), higher number of past year sex partners (AOR = 2.97: 95% CI = 1.21–7.31) and discussing condom use when having sex with partners (AOR = 0.08; 95% CI = 0.01–7.31). This modified ASK model provided better fit than the ASK model, as it explained more variance in HIV testing (47 vs. 29.8%). Recognising factors associated with HIV testing among MMTDs enables us to create suitable public health intervention strategies.  相似文献   
87.
Accurate measurements of HIV prevalence and associated risk factors among hidden and high-risk groups are vital for program planning and implementation. However, only two sampling methods are purported to provide representative estimates for populations without sampling frames: time-location sampling (TLS) and respondent-driven sampling (RDS). Each method is subject to potential biases and questionable reliability. In this paper, we evaluate surveys designed to estimate HIV prevalence and associated risk factors among people who inject drugs (PWID) sampled through TLS versus RDS. In 2012, males aged ≥16 years who reported injecting drugs in the previous month and living in Haiphong, Vietnam, were sampled using TLS or RDS. Data from each survey were analyzed to compare HIV prevalence, related risk factors, socio-demographic characteristics, refusal estimates, and time and expenditures for field implementation. TLS (n = 432) and RDS (n = 415) produced similarly high estimates for HIV prevalence. Significantly lower proportions of PWID sampled through RDS received methadone treatment or met an outreach worker. Refusal estimates were lower for TLS than for RDS. Total expenditures per sample collected and number of person-days of staff effort were higher for TLS than for RDS. Both survey methods were successful in recruiting a diverse sample of PWID in Haiphong. In Vietnam, surveys of PWID are conducted throughout the country; although the refusal estimate was calculated to be much higher for RDS than TLS, RDS in Haiphong appeared to sample PWID with less exposure to services and required fewer financial and staff resources compared with TLS.  相似文献   
88.

Purpose

To describe total fluid intake (TFI) according to socio-demographic characteristics in children and adolescents worldwide.

Methods

Data of 3611 children (4–9 years) and 8109 adolescents (10–18 years) were retrieved from 13 cross-sectional surveys (47 % males). In three countries, school classes were randomly recruited with stratified cluster sampling design. In the other countries, participants were randomly recruited based on a quota method. TFI (drinking water and beverages of all kinds) was obtained with a fluid-specific record over 7 consecutive days. Adequacy was assessed by comparing TFI to 80 % of adequate intake (AI) for total water intake set by European Food Safety Authority. Data on height, weight and socio-economic level were collected in most countries.

Results

The mean (SD) TFI ranged from [1.32 (0.68)] to [1.35 (0.71)] L/day. Non-adherence to AIs for fluids ranged from 10 % (Uruguay) to >90 % (Belgium). Females were more likely to meet the AIs for fluids than males (4–9 years: 28 %, OR 0.72, p = 0.002; 10–18 years: 20 %, OR 0.80, p = 0.001), while adolescents were less likely to meet the AI than children (OR 1.645, p < 0.001 in males and OR 1.625, p < 0.001 in females).

Conclusions

A high proportion of children and adolescents are at risk of an inadequate fluid intake. This risk is especially high in males and adolescents when compared with females or children categories. This highlights water intake among young populations as an issue of global concern.
  相似文献   
89.
<正>多重耐药菌即1种微生物对3类(比如氨基糖苷类、红霉素、β-内酰胺类)或3类以上抗菌药物同时耐药。随着抗菌药物应用日益广泛,细菌耐药性已成为国际、国内医院感染和社区感染普遍存在的问题。对于难治性(多重耐药菌感染)创口的治疗,某中医院普通外科采取中医特色自制黄连纱条对难治性感染创口进行治疗。2010—2014年共治疗25例难治性创口感染患者,均已进行分泌物细菌培  相似文献   
90.
To assess the place of allogeneic hematopoietic stem cell transplantation (HSCT) in the advanced stage of acute myeloid leukemia (AML), we retrospectively analyzed 379 consecutive patients who underwent allogeneic HSCT for advanced AML. The median follow-up of the entire cohort was 7.5 years. Sixty-nine patients (18%) were transplanted with primary resistant disease. Three hundred and ten (82%) were relapsed patients, 94 (30%) of whom were in untreated relapse, 67 (22%) in refractory relapse and 149 (48%) in 2nd or 3rd complete remission at time of transplantation. The 5-year probabilities of overall survival (OS), disease-free survival (DFS), and transplant-related mortality (TRM) were 22 +/- 4%, 20 +/- 4%, 45 +/- 6%, respectively. In multivariate analysis, we demonstrated the favorable impact on OS, DFS and TRM of two factors over which we have no control (age <15 years, complete remission achievement) and three factors over which we have some control (female donor, acute and chronic graft-versus-host disease). The results of this study suggest that the graft-versus-leukemia effect is important in advanced AML and that new HSCT modalities are needed for some patients with this indication.  相似文献   
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