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81.
82.
Poly(2-vinylpyridine-b-methylmethacrylate) coated gold nanoparticles [P(2VP-MMA)-AuNPs] were prepared and characterized by UV-Vis, FTIR, AFM, and zetasizer analysis. Investigation of the potential of the synthesized poly(2-vinylpyridine-b-methylmethacrylate) coated gold nanoparticles [P(2VP-MMA)-AuNPs] for detection of nicotine is the main focus of the current study. P(2VP-MMA)-AuNPs were coated on a glassy carbon electrode (GCE) for electrochemical detection of nicotine by cyclic voltammetry. The effect of molar mass of individual P2VP blocks and total molar mass of the block copolymer is evaluated in the context of an enhanced electrochemical response of the modified GCE for its sensing ability of nicotine in both aqueous and organic media. The electrochemical detection of nicotine is significantly enhanced by modification of the GCE with P(2VP-MMA)-AuNPs.

Poly(2-vinylpyridine-b-methylmethacrylate) coated gold nanoparticles [P(2VP-MMA)-AuNPs] are employed for enhancement of electrochemical response of glassy carbon electrode for nicotine.  相似文献   
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Obstructive sleep apnea (OSA) and increased left atrial volume (LAV) both independently increase cardiovascular mortality. We hypothesized that treatment of OSA with continuous positive airway pressure (CPAP) may decrease LAV. We retrospectively identified 47 OSA patients receiving CPAP who had echocardiograms done before and after polysomnography. Compliance was defined as CPAP use at-least five nights weekly and 5 h per night. The compliant group (n = 23) had a significant decrease in diastolic blood pressure (DBP; 4.4 ± 8.9 mmHg, p < 0.05) and mean arterial pressure (MAP; 4.7 ± 10.3 mmHg, p < 0.05), while no significant changes were observed in the noncompliant group (n = 24). LAV data were available in 13 compliant and 20 noncompliant patients. LAV decreased nonsignificantly (3.54 ± 16.6 mL, n = 13, p = 0.65) in CPAP-compliant patients, while it increased (15.47 ± 22.3 mL, n = 20, p < 0.006) in noncompliant patients. Similar changes were seen in the LAV index. Untreated OSA was associated with an increase in LAV and LAV index without significant changes in blood pressure. Treatment of OSA was associated with a decrease in DBP and MAP with a nonsignificant decrease in LAV. Treatment of OSA may prevent adverse left atrial remodeling. There are no conflicts of interest or financial disclosures for any of the authors.  相似文献   
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Child marriage (before 18 years) is prevalent in Pakistan, which disproportionately affects young girls in rural, low income and low education households. Our study aims to determine the association between early marriage and high fertility and poor fertility health indicators among young women in Pakistan beyond those attributed to social vulnerabilities. Nationally representative data from Pakistan Demographic and Health Survey, 2006–2007, a cross-sectional observational survey, were limited to ever-married women aged 20–24 years (n = 1,560; 15 % of 10,023) to identify differences in poor fertility outcomes [high fertility (three or more childbirths); rapid repeat childbirth (<24 months between births); unwanted pregnancy (any ever); pregnancy termination (any stillbirth, miscarriage or abortion ever)] by early (<18) versus adult (≥18) age at marriage. Associations between child marriage and fertility outcomes were assessed by calculating adjusted odds ratios (AORs) using logistic regression models after controlling for demographics, social equity indicators (education, wealth index, rural residence), contraception use, marriage duration and culture-specific factors (husband’s desire for more children, son preference). Overall, 50 % of ever-married women aged 20–24 years in Pakistan were married before the age of 18 years. Girl child marriage was significantly (p < 0.001) associated with low social equity indicators (poverty, rural residence, and no formal education). Adjusted logistic regression models showed that girl child marriage was significantly associated with high fertility (AOR 6.62; 95 % CI 3.53–12.43), rapid repeat childbirth (AOR 2.88; 95 % CI 1.83–4.54), unwanted pregnancy (AOR 2.90; 95 % CI 1.75–4.79), and pregnancy termination (AOR 1.75; 95 % CI 1.10–2.78). Girl child marriage affects half of all ever-married women aged 20–24 years in Pakistan, and increases their risk for high fertility and poor fertility health indicators, highlighting the need of increasing the age of marriage among women in Pakistan. Efforts to eliminate girl child marriage by strict law enforcement, promoting civil, sexual and reproductive health rights for women can help eliminate girl child marriage in Pakistan.  相似文献   
87.
Dementia is one of the major causes of personal, societal and financial dependence in older people and in today’s ageing society there is a pressing need for early and accurate markers of cognitive decline. There are several subtypes of dementia but the four most common are Alzheimer’s disease, Lewy body dementia, vascular dementia and frontotemporal dementia. These disorders can only be diagnosed at autopsy, and ante-mortem assessments of “probable dementia (e.g. of Alzheimer type)” are traditionally driven by clinical symptoms of cognitive or behavioural deficits. However, owing to the overlapping nature of symptoms and age of onset, a significant proportion of dementia cases remain incorrectly diagnosed. Misdiagnosis can have an extensive impact, both at the level of the individual, who may not be offered the appropriate treatment, and on a wider scale, by influencing the entry of patients into relevant clinical trials. Magnetic resonance imaging (MRI) may help to improve diagnosis by providing non-invasive and detailed disease-specific markers of cognitive decline. MRI-derived measurements of grey and white matter structural integrity are potential surrogate markers of disease progression, and may also provide valuable diagnostic information. This review summarises the latest evidence on the use of structural and diffusion MRI in differentiating between the four major dementia subtypes.  相似文献   
88.

Background

The Glasgow Coma Scale (GCS) is the most widely accepted scale for assessing levels of consciousness, clinical status, as well as prognosis of traumatic brain injury (TBI) patients. The Full Outline of UnResponsiveness (FOUR) score is a new coma scale developed addressing the limitations of the GCS. The aim of this prospective cohort study was to compare the performance of the FOUR score vs. the GCS in predicting TBI outcomes.

Methods

From April to July 2011, 60 consecutive adult patients with TBI admitted to the Alexandria Main University Hospital intensive care units (ICU) were enrolled in the study. GCS and FOUR score were documented on arrival to emergency room. Outcomes were in-hospital mortality, unfavorable outcome [Glasgow outcome scale extended (GOSE) 1–4], endotracheal intubation, and ICU length of stay (LOS).

Results

Fifteen (25 %) patients died and 35 (58 %) had unfavorable outcome. When predicting mortality, the FOUR score showed significantly higher area under receiver operating characteristic curve (AUC) than the GCS score (0.850 vs. 0.796, p = 0.025). The FOUR score and the GCS score were not different in predicting unfavorable outcome (AUC 0.813 vs. 0.779, p = 0.136) and endotracheal intubation (AUC 0.961 vs. 0.982, p = 0.06). Both scores were good predictors of ICU LOS (r 2 = 0.40 [FOUR score] vs. 0.41 [GCS score]).

Conclusions

The FOUR score was superior to the GCS in predicting in-hospital mortality in TBI patients. There was no difference between both scores in predicting unfavorable outcome, endotracheal intubation, and ICU LOS.  相似文献   
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Objectives: Global burden of childhood asthma has increased in the past few decades, particularly in low-income countries. In Pakistan, there is a lack of community-based epidemiological studies estimating the burden of asthma among children. This study determined the prevalence and predictors of asthma among children 3–17 years of age in Karachi, Pakistan. Methods: A two-stage community-based representative cross-sectional survey was conducted in Karachi from March 2012 to April 2013 comprising 1046 children aged 3–17 years. Of 7500 clusters, 80 were randomly selected, and of these, 15 children per cluster were enrolled randomly. A translated and pre-tested version of International Study of Asthma and Allergies in Children questionnaire was administered. Results: The overall prevalence of asthma among study participants was 10.2% (95% CI: 8.4–12.0). Asthma was more likely to occur among boys (adj. OR: 2.5, 95% CI: 1.6–4.0), children in the younger age group (3–7 years) (adj. OR: 2.9, 95% CI: 1.7–4.8), those living in households with ill-ventilated kitchens (adj. OR: 1.8, 95% CI: 1.1–3.1), having family history of asthma (adj. OR: 2.3, 95% CI: 1.3–3.9) and those of the Sindhi ethnicity (adj. OR: 2.2, 95% CI: 1.1–4.4). Conclusion: This study is the first robust evidence regarding asthma among children in Pakistan, reporting a high burden in this group. Family history, male gender, Sindhi ethnicity and ill-ventilated kitchen were identified as important predictors of asthma. Targeted preventive measures and intervention studies are required to better understand and reduce the burden of asthma among children in Pakistan.  相似文献   
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