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1.
Apolipoprotein A-V encoded by apolipoprotein 5 (APOA5) gene plays an important role in lipid metabolism, especially in the regulation of plasma triglycerol levels. The study aimed to evaluate the association of the APOA5-rs662799 polymorphism with dyslipidemia in Vietnamese children and the potential modification of obesity-related traits (body mass index, waist circumference, hip circumference, and waist-to-hip ratio) on this association. A case–control study was conducted with a total of 154 dyslipidemia cases and 389 controls at the age of 6 to 10 recruited at 31 primary schools in Hanoi city of Vietnam. Genotype for APOA5-rs662799 polymorphism was determined by the restriction fragment length polymorphism analysis. The association of APOA5-rs662799 polymorphism with dyslipidemia adjusting for age, sex, residence, and obesity-related traits was analyzed by binary logistic regression analysis. The results showed that in comparison with T/T and T/C carriers, the C/C carriers had a higher concentration of serum TAG in cases (p =0.049). Carriers of the C allele (C/C + T/C) had higher risk for developing dyslipidemia and hypertriglyceridemia than subjects with T/T genotype (odds ratio, OR = 1.7, p =0.0062 and OR = 1.6, p = 0.026, respectively). The association remained significant after adjusting for age, gender, residence, and obesity status (OR = 1.75, p = 0.006 and OR = 1.53, p = 0.049, respectively) or other obesity-related traits. The study suggested that the APOA5-rs662799 polymorphism may be a determinant of dyslipidemia and hypertriglyceridemia in Vietnamese children, independent of obesity-related traits.  相似文献   
2.
PURPOSE: The objective of this study was to assess the accuracy of color-flow duplex surveillance parameters to detect infrainguinal vein graft stenoses and to investigate whether graft revision without angiography is justified. METHODS: In a prospective study in which three centers participated, the data of graft surveillance in 300 patients were analyzed. For the evaluation of surveillance criteria all patients underwent a digital subtraction angiography if a graft stenosis was suspected. To create a control group, in patients with normal grafts a consented digital subtraction angiography was performed also. From these data the accuracy of seven duplex and three ankle blood pressure-derived variables was assessed. The relation between various surveillance criteria and continued graft patency was determined with life table analysis with the transient state method. RESULTS: The mean follow-up period was 20 months (range, 1 to 40 months). At univariate and multivariate analysis the peak systolic velocity (PSV) ratio provided the best correlation with angiographic stenoses > or = 70% (PSV ratio cutoff 3.0: sensitivity 80%, specificity 84%). This finding did not differ between the participating centers. With life table methods it was demonstrated that the best combination of efficacy (limitation of the number of unnecessary revisions), safety (minimal number of correctable lesions missed), and reduction of angiograms was obtained by a two-parameter surveillance algorithm. This algorithm included a PSV ratio < 2.5 to delineate patients in whom a conservative approach without angiography or revision was appropriate, a PSV ratio > or = 4.0 to indicate patients in whom vein graft revision without angiography could be scheduled, and a group with PSV ratios between 2.5 and 4.0 in whom angiography was to be performed to determine clinical management on the basis of the stenosis severity. This algorithm had a positive predictive value of 93% and a negative predictive value of 89%. In addition, it resulted in a reduction of the number of angiograms of 49% compared with a policy of angiographies in all patients with a PSV ratio > or = 2.5. CONCLUSIONS: The best criterion to identify a failing graft is the PSV ratio. With a two-parameter algorithm for vein graft surveillance, the incidence of unnecessary revisions and of missed high-grade lesions was acceptably low, whereas the number of angiograms was reduced by one half.  相似文献   
3.
The multiple-dose pharmacokinetics of ceftazidime (CAZ) (administered twice daily in a 50 mg/kg of body weight i.v. dose) were studied in 10 severely asphyxiated term infants with suspected septicemia on d 3 of life. Nine term infants with suspected septicemia but without asphyxia served as controls. Blood samples were collected from an arterial catheter at 0, 0.5, 1, 2, 4, 8, and 12 h after an i.v. bolus injection. A high performance liquid chromatography method was used to determine CAZ concentrations from serum. CAZ pharmacokinetics followed a one-compartment open model. The GFRs of all infants were simultaneously studied by means of the 24-h continuous inulin infusion technique. Elimination serum half-life (5.86 +/- 1.13 h versus 3.85 +/- 0.40 h) and serum trough concentrations (46 +/- 14 mg/L versus 23 +/- 7 mg/L) of CAZ were significantly (p < 0.001) increased in the asphyxiated newborn, whereas total body clearance of CAZ (128.4 +/- 25.1 mL/h versus 205.7 +/- 55.4 mL/h), CAZ clearance per kg (40.9 +/- 6.1 mL/h/kg versus 60.8 +/- 8.3 mL/h/kg), and the GFR expressed in mL/min (3.14 +/- 0.43 versus 4.73 +/- 0.89) were significantly (p < 0.001) decreased in the asphyxiated newborn. We conclude that twice daily administration of 50 mg/kg of body weight CAZ given to asphyxiated term newborns in the first days of life results in significantly higher serum trough levels in comparison with control infants. The impaired CAZ clearance is a result of a significantly decreased GFR.  相似文献   
4.
Only limited data are available on chromosomes specifically involved in the multistep tumorigenesis of prostate cancer. To investigate the cytogenetic status at different stages of prostatic tumor development, we have applied interphase in situ hybridization (ISH) with a set of (peri) centromeric DNA probes--specific for chromosomes 1, 7, 8, and Y--to routinely processed tissue sections of prostatic specimens from 75 different individuals. Our panel consisted of: 16 normal/benign prostatic hyperplasia specimens; 23 primary, localized, prostatic tumors (N0M0 stage); 20 regional lymph node metastases (M0 stage); and 16 distant metastases. Numerical aberrations of at least one chromosome were not observed in normal/benign prostatic hyperplasia cases, but were present in localized tumors (39%), regional lymph node metastases (40%), and distant metastases (69%). Within the different pTNM groups, we observed the following aberrations (listed, within each series, in decreasing order of frequency): -Y, +8, -8, +7 in primary tumors; +8, +7, -Y, +Y, -8 in regional lymph node metastases; and +8, +7, +1, -Y, -8 in distant metastases. In primary tumors, the number of aberrant cases increased significantly with local tumor stage (p < 0.05). A significant increase in gain of chromosome 8 was also observed (p < 0.02). Gain of chromosome 7 and/or 8 showed a significant increase with progression of local tumor stage (p < 0.02). Specific involvement of chromosome 8 was seen in bone metastases, but not in hematogenous metastases to other sites (p = 0.02). Comparative genomic hybridization analysis of these bone metastases disclosed centromere 8 gains as amplifications of the (whole) 8q arm, whereas centromeric loss appeared to be due to loss of 8p sequences. With progression toward metastatic disease, an accumulation of genetic changes was seen as exemplified by gain of chromosome 1, which was solely observed in distant metastases. With tumor progression, gain of chromosomes 7 and/or 8 significantly increased (p = 0.03), whereas the number of cases with aberrations of the Y chromosome did not change. Furthermore, ploidy status determined by ISH revealed a significant increase in the number of aneuploid cases along with advancement of pTNM stage (p = 0.04). Collectively, the data strongly suggest that: (a) gain of chromosome 7 and/or 8 sequences is implicated in prostatic tumor progression; (b) gain of chromosome 8 sequences is related to local tumor growth; (c) overrepresentation of 8q sequences, most likely by isochromosome 8q formation, is involved in metastatic spread to the bone; and (d) changes in the centromeric copy number, as detected by interphase ISH, might in some cases represent structural alterations, such as an isochromosome.  相似文献   
5.
OBJECTIVE: To evaluate whether the Waterlow pressure sore risk (PSR) scale has prognostic significance for intensive care patients. DESIGN: A prospective study. SETTING: The surgical intensive care unit (ICU) of the University Hospital Rotterdam. PATIENTS: Data were evaluated from 594 patients who had been admitted to the ICU during the year 1994. METHODS AND RESULTS: Each patient was assessed daily with respect to their Waterlow PSR score and the development of pressure sores in the sacral region. Actuarial statistical methods were used to analyse the predictive value of the risk score. When a patient had a Waterlow PSR score > 25 on admission, the risk of developing a pressure sore was significantly increased compared to patients with a PSR score < 25. After admission, the daily Waterlow PSR scores obtained were significantly associated with the risk of developing a pressure sore. For each additional point this risk increased by 23% (95% confidence interval 17 to 28%). CONCLUSIONS: The Waterlow PSR scale provides the medical and nursing staff at an early stage with reliable information about the risk patients have in developing a pressure sore.  相似文献   
6.
BACKGROUND/AIMS: Treatment with ursodeoxycholic acid has been shown to decrease the rate of disease progression in patients with primary biliary cirrhosis, although the effect is modest. Since primary biliary cirrhosis has many features of an autoimmune disorder, immunosuppressives added to ursodeoxycholic acid may be of value in the treatment of primary biliary cirrhosis. METHODS: A 1-year randomized, double-blind, placebo-controlled trial was carried out in 50 patients with primary biliary cirrhosis, who had already been treated with ursodeoxycholic acid for at least 1 year, but had not achieved complete disease remission. Patients were randomized to additional prednisone (30 mg per day initially, tapered to 10 mg daily after 8 weeks) and azathioprine (50 mg daily) or placebo. A subgroup of patients received cyclical etidronate and calcium. The principal aim of the study was to assess the short-term benefits and risks of the combined bile acid and low-dose immunosuppressive regimen. Primary endpoints were effects on symptoms, liver biochemistry, liver histology, bone mass and the occurrence of adverse events. RESULTS: Pruritus (p=0.02), alkaline phosphatase, aspartate aminotransferase, IgM and procollagen-III-propeptide improved significantly (all p<0.002) in the combined treatment group as compared to the placebo group. Histological scores for disease activity and disease stage decreased significantly within the combination treatment group (p<0.001). CONCLUSIONS: In patients with primary biliary cirrhosis receiving ursodeoxycholic acid, there is an additional beneficial effect of 1-year treatment with prednisone and azathioprine on symptoms and biochemical, fibrogenetic and histological parameters. These results strongly encourage the evaluation of this triple treatment regimen in long-term controlled trials of adequate size to document its effect on clinical events.  相似文献   
7.
The orthogonality relationship for modes in waveguide containing inhomogeneous bianisotropic materials is derived using the concept of linear operators. The properties of the associated adjoint waveguide are explored. The results are restricted to cases where there exists axial independency of all parameters.  相似文献   
8.
A novel approach for on-line introduction of internal standard (IS) for quantitative analysis using LC-MS/MS has been developed. In this approach, analyte and IS are introduced into the sample injection loop in different steps. Analyte is introduced into the injection loop using a conventional autosampler (injector) needle pickup from a sample vial. IS is introduced into the sample injection loop on-line from a microreservoir containing the IS solution using the autosampler. As a result, both analyte and IS are contained in the sample loop prior to the injection into the column. Methodology allowed to reliably introduce IS and demonstrated injection accuracy and precision comparable to those obtained using off-line IS introduction (i.e., IS and analyte are premixed before injection) while maintaining chromatographic parameters (i.e., analyte and IS elution time and peak width). This new technique was applied for direct analysis of model compounds in rat plasma using on-line solid-phase extraction (SPE) LC-MS/MS quantification. In combination with on-line SPE, IS serves as a surrogate IS and compensates for signal variations attributed to sample preparation and instrumentation factors including signal suppression. The assays yielded accuracy (85-119%), precision (2-16%), and analyte recovery comparable to those obtained using off-line IS introduction. Furthermore, on-line IS introduction allows for nonvolumetric sample (plasma) collection and direct analysis without the need of measuring and aliquoting a fixed sample volume prior to the on-line SPE LC-MS/MS analysis. Therefore, this methodology enables direct sample (plasma) analysis without any sample manipulation and preparation.  相似文献   
9.
Assembling printed circuit boards efficiently using automated placement machines is a challenging task. Here, we focus on a motion control problem for a specific type of placement machines. More specifically, the problem is to establish movement patterns for the robot arm, the feeder rack, and—when appropriate—the worktable, of a sequential pick-and-place machine. In this note we show that a (popular) greedy strategy may not always yield an optimum solution. However, under the relevant Tchebychev metric, we can model the problem as a linear program, thereby establishing the existence of a polynomial time algorithm for this motion control problem. Finally, we give experimental evidence that computing optimal solutions to this motion control problem can yield significantly better solutions than those found by a greedy method.  相似文献   
10.
The clinical characteristics of and outcome for 75 children with meningococcal septic shock were studied. In addition, a new prognostic scoring system was developed. The median age of the patients was 3.2 years (range, 3 weeks to 17.9 years). The most common phenotype of Neisseria meningitidis was B:4:P1.4 (27%). A mortality rate of 21% was observed. Ten (17%) of the 59 survivors had serious sequelae. Calcium levels were significantly lower in patients with seizures. Disseminated intravascular coagulation occurred in 58% of the patients who were tested. Logistic regression analysis identified four laboratory features independently associated with mortality: serum C-reactive protein level, base excess, serum potassium level, and platelet count. These features were used to develop a novel scoring system with a predictive value for death and survival of 71% and 90%, respectively. The outcome was predicted correctly for 86% of the patients, which is higher than rates previously reported for scoring systems.  相似文献   
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