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71.
A speciation procedure for chromium(III) and chromium(VI) in the water and food samples has been established in the presented work. The procedure presented based on quantitative recoveries of Cr(III) > 95% using coprecipitation of Ni2+/2-Nitroso-1-naphthol-4-sulfonic acid. The total chromium was measured after reduction of Cr(VI) by concentrated H2SO4 and ethanol. The Cr(VI) was calculated as the difference between the total Cr content and the Cr(III) contents. The analytical variables, pH, amounts of precipitate, sample volume for optimum recoveries of Cr(III) were investigated. The influences of the some alkaline and earth alkaline ions and some transition metals on the recoveries of analyte ions were also investigated. The preconcentration factor was 50. The detection limit (3σ) of the reagent blank for chromium(III) was 1.33 μg L−1. The relative standard deviations for determinations were found to be <7%, and % of relative error was calculated <6%. The method was validated by certified reference materials of tea (GBW 07605) and bush branches and leaves (GBW 0703). The procedure was successfully applied to the speciation of chromium in natural water and food samples (fish, white cheese, cow’s meat, black tea, boiled wheat).  相似文献   
72.
73.
BACKGROUND: Diagnosis of tuberculous pleuritis is difficult because of its nonspecific clinical presentation and decreased efficiency of traditional diagnostic methods. We investigated the use of procalcitonin (PCT) concentration in tuberculous pleuritis diagnosis. METHODS: A prospective clinical study was performed with two different patient groups. A total of 28 patients were included: 18 with tuberculosis and 10 with nontuberculous pleurisy. Serum and pleural fluid PCT concentrations were evaluated before treatment. RESULTS: Serum and pleural fluid PCT concentrations were statistically different between tuberculous and nontuberculous pleurisy groups (P = 0.012 and P = 0.004, respectively), even though they were not elevated in relation to the cut-off level of 0.5 ng/mL. A positive and significant correlation was detected between serum and pleural fluid PCT levels (r = 0.49, P = 0.008). Diagnostic specificity and sensitivity values for serum and pleural fluid PCT in discriminating tuberculous from nontuberculous pleurisy were 80% and 72.2%, and 90% and 66.7% at the 0.081 and 0.113 ng/mL cut-off values, respectively. CONCLUSION: Relative to the current cut-off level of 0.5 ng/mL, PCT concentration is not a useful parameter for the diagnosis of tuberculous pleurisy. Because there were PCT levels in patients with tuberculous pleurisy that were below the current cut-off level but were significantly different from those of the nontuberculous group, the use of PCT should be further investigated.  相似文献   
74.
The present study aimed to evaluate the late-term changes in radial artery luminal diameter (RAD) and vasodilatation response following transradial catheterization (TRC). TRC-inducing trauma to radial artery intima may trigger chronic phase vascular changes and lead to anatomical and functional impairment. There is controversial data whether the impairment persists or repairs later. Fifty-six consecutive patients undergoing TRC were enrolled prospectively. Baseline RAD, flow-mediated dilatation (FMD) and nitroglycerin-mediated dilatation (NMD) of the radial artery at the access site were measured before TRC by high-resolution ultrasound. Six months later; RAD, FMD and NMD were measured again at the same access site. RAD at the sixth month was reduced compared with pre-procedural measurements (2.85 ± 0.44 versus 2.74 ± 0.42 mm, p = 0.0001).The average FMD decreased to 5.66 ± 5.87 %, which was significantly lower than the observed pre-procedural FMD (9.45 ± 5.01 %) 6 months after TRC (p = 0.0001). Likewise, the average NMD at the sixth month was reduced compared with pre-procedural NMD (9.52 ± 6.77 versus 6.64 ± 6.51 %, p = 0.018). Logistic regression analysis indicated that pre-procedural radial artery diameter to sheath size ratio was the independent predictor of NMD reduction (95 % confidence interval, β = ?9.74, p = 0.024). TRC may lead to a significant luminal diameter reduction and impairment of vasodilatation response in the radial artery at late term.  相似文献   
75.

Introduction  

The association between hyperuricemia and cardiovascular disease in hypertensive subjects is controversial. Attempts to elucidate the possible association between hyperuricemia and early atherosclerosis in hypertensive patients may provide alternative prevention or therapy targets for future cardiovascular events.  相似文献   
76.
77.
Background: Insulin detemir is a basal insulin analog designed to produce a superior pharmacokinetic profile to basal formulations of human insulin. It has shown consistently improved tolerability in comparison to neutral protamine Hagedorn (NPH) insulin in adult cohorts, but there are relatively few publications involving pediatric cohorts. Methods: The efficacy and safety of insulin detemir in children with type 1 diabetes was assessed using data from the Turkish cohort of PREDICTIVE? (a large, multinational, observational) study. The children investigated were using basal–bolus therapy involving NPH insulin or insulin glargine at baseline but were switched to insulin detemir as part of routine clinical care by their physicians. Results: Twelve weeks of treatment with insulin detemir significantly reduced mean hemoglobin A1c (9.7–8.9%, p < 0.001) and mean fasting glucose [185–162 mg/dL (10.3–9 mmol/L), p < 0.01]. Fasting glucose variability was also lower after treatment with insulin detemir than previously (on either NPH or glargine, p < 0.05). The frequencies of total, major and nocturnal hypoglycemic events were significantly reduced with insulin detemir relative to baseline, with an estimated mean of 6.89 fewer events/patient/yr overall (p < 0.001) and 2.6 fewer nocturnal events/patient/yr (p < 0.01). Weight and insulin dose remained relatively unchanged. Conclusions: Twelve weeks of treatment with insulin detemir improved glycemic control and reduced hypoglycemia in children with type 1 diabetes. This improved tolerability might allow further dose titration and therefore additional improvements in glucose control.  相似文献   
78.

Purpose

The present study aimed to evaluate whether combining the magnetic-activated cell sorting (MACS) with density-gradient (DG) or swim-up (SU) sperm separation techniques can improve sperm selection to obtain higher quality spermatozoa.

Methods

Two commonly used sperm selection techniques, SU and DG, were compared to MACS combined with either SU or DG. Spermatozoa obtained from normozoospermic (n?=?10) and oligozoospermic (n?=?10) cases were grouped as SU, DG, SU+MACS, and DG+MACS followed by the analysis of sperm morphology, motility, DNA integrity, and the levels of Izumo-1 and PLCZ proteins.

Results

Although spermatozoa obtained by SU or DG when combined with MACS have improved aspects when compared to SU or DG alone, results did not reach a statistically significant level. Moreover, separation with MACS caused a significant loss in the numbers of total and rapid progressive spermatozoa.

Conclusions

Considering the cost/benefit ratio, MACS application together with traditional techniques may only be preferred in certain cases having higher concentrations of spermatozoa, but it does not seem to be an ideal and practical sperm selection technique for routine use.
  相似文献   
79.
Objective: The main aim of this study was to investigate the first trimester maternal serum secreted frizzle-related protein-5 (Sfrp-5) levels and to evaluate the predictive value on the subsequently developed gestational diabetes mellitus (GDM).

Methods: A total of 40 pregnant women who subsequently developed GDM and 44 age- and pre-pregnancy BMI-matched healthy pregnant women were enrolled in this prospective case-control study. First trimester serum Sfrp-5 levels were evaluated to determine if there is an association with the onset of GDM, by using logistic regression analysis.

Results: Decreased first trimester serum Sfrp-5 levels (OR?=?14.332, 95%CI: 4.166–49.301, p?<?0.001) were found to be significantly associated with the increased risk of GDM. There were no statistically significant differences in serum Sfrp-5 levels between the diet- and insulin-treated GDM groups and also serum Sfrp-5 levels were not found to be predictive for adverse perinatal outcomes (p?>?0.05).

Conclusions: Decreased first trimester serum Sfrp-5 levels are significantly associated with the increased risk of GDM.  相似文献   
80.
The efficacy of intracytoplasmic sperm injection (ICSI) employingtesticular and ejaculated spermatozoa was assessed in 24 coupleswith totally or initially immotile spermatozoa. No criteriawere employed in selecting which patients would be treated withtesticular or ejaculated spermatozoa. The men were chosen atrandom. Testicular spermatozoa obtained by testicular spermextraction were used in 14 and ejaculated spermatozoa were usedin 10 of these couples. In all cases, asthenozoospermia wastotal in their basal semen sample. In 12 male partners, spermatozoawere totally immotile before and after Percoll gradient fractionation(totally immotile). In the remaining 12 men, spermatozoa initiallyshowed a total absence of motility; however, some of the spermatozoahad showed very poor motility (0.1%) after Percoll gradientfractionation and a 13–2.0 h incubation period (initiallyimmotile). Of these 24 total asthenozoospermic males, 14 alsohad total terato-zoospermia. The fertilization and cleavagerates in the testicular and ejaculated sperm groups were 533and 963 and 543 and 94.4% respectively. One cycle resulted incomplete fertilization failure, and in 23 embryo transfer cyclesa total of 10 pregnancies were obtained (41.6%). Eight pregnancieswere achieved in the testicular sperm group, while only twopregnancies were obtained in the ejaculated sperm group. Fourpregnancies, two from the ejaculated sperm group and two fromthe testicular sperm group, resulted in clinical abortions inthe first trimester. Of the remaining six pregnancies, two havealready resulted in healthy births and four pregnancies arenow in the second or third trimester in the testicular spermgroup. Using testicular spermatozoa in combination with ICSIcan be an alternative mode of treatment in cases with totallyor initially immotile spermatozoa in the ejaculate. Very lowpregnancy rates have been obtained and no ongoing pregnancyhas been achieved using ejaculated spermatozoa in these cases.  相似文献   
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