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1.
Abstract: Background : Despite extensive literature on the topic, it is uncertain if grand (para ≥ 5) and great grand (para ≥ 10) multiparity are associated with adverse birth outcomes. We critically evaluate the evidence for and against the existence of adverse maternal and/or fetal outcomes in high parity women. Methods : An electronic search of MEDLINE and other bibliographic databases (Current Contents, EMBASE, and CAB) was conducted, and all relevant articles in English language were retrieved. Results : Findings on the association between high parity and maternal‐fetal birth outcomes are not consistent. Although the older literature tends to suggest that multiparity is a risk factor for negative birth outcomes, more recent reports are not supportive. Comparison across studies was further complicated by confounding factors like maternal age, socioeconomic status, and levels of prenatal care, as well as by variations in study designs and in the definition of parity itself. Furthermore, most studies that examined women of extreme parity (para ≥ 10) were handicapped by inadequate power. Conclusions : After accounting for quality, culture, and degrees of associations, the preponderance of evidence seems to point to possible existence of heightened risk for certain medical complications and placental pathologies among women of extreme parity. The literature also provides reasonable evidence for a higher‐than‐expected likelihood for occurrence of fetal macrosomia with advanced parity.  相似文献   
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BACKGROUND: The diagnosis of hepatitis B virus (HBV) has until recently been based on traditional serologic methods targeting viral antigens and antibodies to viral proteins. The development of molecular methods allowing for the quantitation of HBV DNA is proving clinically valuable for monitoring therapy and detecting early treatment failures. OBJECTIVES: Here we report a new real-time (LightCycler) quantitative PCR for the detection of HBV DNA based on sequence specific hybridisation probes (designed in-house), targeting the HBV surface antigen. STUDY DESIGN: The assay was evaluated using a 10-fold dilution series of standard HBV DNA [Eurohep standard reference 1, genotype A, HBsAg subtype adw with a unitage of 10(6) WHO. i.u./ml] and 89 clinical serum samples. The performance was measured against a quantified standard HBV DNA working reagent (NIBSC code 98/780) and the sensitivity compared with our conventional thermal-block PCR. RESULTS AND CONCLUSION: Real-time PCR detected HBV DNA in 45% (40/89) and thermal-block PCR in 16% (14/75) of clinical samples. Results for 26 samples were below the detection limit of the thermal-block PCR but could be quantified by real-time (LightCycler) PCR. The LightCycler assay was at least 5 logs more sensitive than thermal-block PCR and could detect HBV in a linear range between 5 and 10(7) i.u. per reaction. The broad generic nature of the PCR primers coupled with the enhanced sensitivity and specificity of the fluorescent hybridisation probes makes this assay potentially valuable for both routine diagnostic and epidemiological work.  相似文献   
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Healthcare for the elderly population presents enormous challenges, which are further complicated by ethnicity-related socioeconomic disparities in the United States. We set out to determine the predictors of hospital admissions in the elderly by conducting a retrospective cohort analysis of a nationally representative sample of community-dwelling individuals aged 70 and older in 1984 (n = 7541). Multivariate logistic regression analysis of data from the Longitudinal Study on Aging revealed that race, health status, type of family relationship, and activities of daily living (ADL) are significant predictors of hospitalization among the elderly. Older blacks are less likely to be admitted into the hospital, compared to their white counterparts (OR 0.68, 95%CI 0.52-0.89). Elderly persons who perceive their health status as being fair or poor are three times as likely to be hospitalized than those who perceived their health status as excellent (OR 2.99, 95%CI 2.15-4.15). Those with impairment in activities of daily living are twice as likely to be confined to the hospital than those without impairment (OR 1.78, 95%CI 1.64-1.96). Elderly persons living with nonrelatives are three times as likely to be admitted for short hospital stays than those living with spouses (OR 2.90, 95%CI 1.44-5.82). Future identification of predictors of hospital admissions in the elderly may help characterize those at risk and perhaps allow for focused and timely intervention.  相似文献   
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The anti-Trypanosoma brucei brucei activity in vitro and in vivo of a lactone-rich fraction of Vernonia blumeoides leaves (VBLF) and its potential in alleviating trypanosome-induced anemia and organ damage were investigated. Gas chromatography–mass spectrometry (GC–MS) analysis of VBLF revealed the presence of a number of lactone-containing compounds. In an in vitro study, VBLF showed concentration-dependent activity and was further used to treat T. brucei brucei-infected rats. The VBLF treatments, especially at 300 mg/kg body weight (BW), significantly (P < 0.05) kept the parasites reduced during the entire experimental period compared with the infected untreated group. At the end of the experiment, the trypanosome-induced anemia and hepatic damage were significantly (P < 0.05) alleviated in all the VBLF treatment groups, but renal damage was only prevented in the 200 and 300 mg/kg BW treatment groups. Furthermore, the trypanosome-induced increase in the relative weights of liver, spleen and kidney were significantly (P < 0.05) alleviated by the 300 mg/kg BW VBLF treatment. It was concluded that orally administered VBLF, especially at 300 mg/kg BW, possessed antitrypanosomal activity and could alleviate parasite-induced anemia and organ damage.  相似文献   
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Objective: To determine if there was any difference in SpO2 readings during exchange blood transfusion (EBT).Methods: A prospective cross-sectional study of neonates with severe neonatal jaundice requiring EBT was conducted. Oxygen saturation was recorded before, immediately and 15 minutes after EBT by using a pulse oximeter. Results: This study included 30 neonates with 20 males and 10 females. The age ranged from 1 to 12 days with a mean of (5.4 ± 2.9) days. Pre-EBT SpO2 ranged from 90% to 98% with a mean value of (94.3 ± 2.2)%; SpO2 in the end of EBT ranged from 85% to 99% with a mean value of (94.1 ± 3.2)%; SpO2 at 15 minutes after EBT ranged from 77% to 99% with a mean value of (94.8 ± 4.1)%. There was no significant difference between SpO2 values at onset of EBT and either immediately or 15 minutes after EBT (P=0.770 and 0.422, respectively). SpO2 showed no significant difference between neonates who were infused with blood of different storage times (<24 h or ≥24 h) at the onset of EBT (P=0.584), immediately (P>0.999) and 15 minutes after EBT (P=0.887). Besides, SpO2 values were compariable in neonates with hematocrit <45% or ≥45% at the onset of EBT (P=0.284), immediately (P=0.118) and 15 minutes after EBT (P=0.868). Conclusions: EBT does not affect SpO2 in neonates.  相似文献   
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Development of homogenous metal matrix nanocomposites with uniform distribution of nanoreinforcement, preserved matrix nanostructure features, and improved properties, was possible by means of innovative processing techniques. In this work, Al-SiC nanocomposites were synthesized by mechanical milling and consolidated through spark plasma sintering. Field Emission Scanning Electron Microscope (FE-SEM) with Energy Dispersive X-ray Spectroscopy (EDS) facility was used for the characterization of the extent of SiC particles’ distribution in the mechanically milled powders and spark plasma sintered samples. The change of the matrix crystallite size and lattice strain during milling and sintering was followed through X-ray diffraction (XRD). The density and hardness of the developed materials were evaluated as function of SiC content at fixed sintering conditions using a densimeter and a digital microhardness tester, respectively. It was found that milling for 24 h led to uniform distribution of SiC nanoreinforcement, reduced particle size and crystallite size of the aluminum matrix, and increased lattice strain. The presence and amount of SiC reinforcement enhanced the milling effect. The uniform distribution of SiC achieved by mechanical milling was maintained in sintered samples. Sintering led to the increase in the crystallite size of the aluminum matrix; however, it remained less than 100 nm in the composite containing 10 wt.% SiC. Density and hardness of sintered nanocomposites were reported and compared with those published in the literature.  相似文献   
10.
Apparent resistant hypertension (ARH) is rife among people living with hypertension and is associated with significant morbidity and mortality. There is however paucity of data from sub‐Saharan Africa on the burden of ARH. We sought to report on the frequency and factors associated with ARH among a cohort of Ghanaians with hypertension. A cross‐sectional study involving 2912 participants with hypertension enrolled at five health facilities in Ghana. ARH was defined as either office BP ≥ 140/90 mm Hg on 3 or more antihypertensive medications or on 4 or more antihypertensive medications regardless of BP. Factors associated with ARH were evaluated in a multivariate logistic regression model. We found 550 out of 2,912 (18.9%) of study participants had ARH. Out of these 550 subjects, 511 (92.9%) were on 3 or more antihypertensive medications with BP ≥ 140/90 mm Hg and 39 (7.1%) were on 4 or more antihypertensive medications with BP ≥ 140/90 mm Hg. The prevalence of ARH was 15.5% among elderly aged 75 + years (n = 341), 20.7% among 65‐74 years (n = 588), and 18.9% among those ≤ 64 years (n = 1983). The adjusted odds ratio (95% CI) of factors independently associated with ARH was duration of hypertension, 1.05 (1.03‐1.06) for each year rise; eGFR < 60 mL/min, 1.73 (1.33‐2.25); and diabetes mellitus, 0.59 (0.46‐0.76). Attaining secondary level education and residence in a peri‐urban setting were significantly associated with ARH though not in a dose‐dependent manner. ARH is rife among Ghanaians and may negatively impact on cardiovascular outcomes in the long term.  相似文献   
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