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91.
The cement industry has brought serious environmental pollution problems. In the background of ecological civilization, accelerating rational use of waste resources plays an important role in protecting the environment. In this study, self-compacting concrete (SCC) is prepared using fly ash and lime powder as supplementary cementitious materials by replacing 50%, 60%, and 70% of ordinary Portland cement. By systematically analyzing the influence of the fly ash replacement rate on the workability and mechanical properties of SCC, steel-fiber-reinforced SCC containing 60% fly ash is chosen for further study, and steel fiber is added at the percentages of 0.25%, 0.50%, 0.75%, and 1.00%. The performances in fresh and hardened states are investigated in terms of workability, compressive strength, splitting tensile strength, flexural strength, and axial compression deformation property. The obtained outcomes indicate that although the incorporation of fly ash can improve the workability of the mixture, there is a negative correlation between the mechanical properties of SCC and the fly ash replacement rate. For steel-fiber-reinforced SCC containing 60% fly ash, when the content of steel fibers exceeds 0.75%, the workability decreases sharply, and even when the volume fraction is 1.00%, the passing ability cannot meet the requirements of the technical specifications for applications of self-compacting concrete. The analysis results for mechanical properties show that compressive strength is not changed significantly with increasing percentage of steel fibers. The steel fibers strengthen splitting tensile strength and flexural strength significantly, and compared with that of without steel fibers, they increased by 22% and 58%, respectively, with steel fibers up to 1.00%. Additionally, the parameters of the axial compression deformation property are improved by introducing steel fibers, especially the strain energy (Vε) and relative toughness (Γ) of steel-fiber-reinforced SCC containing a high level of fly ash.  相似文献   
92.
We examined the association between orthostatic hypotension (OH) at baseline examination (1987–1989) and the incidence of coronary heart disease (CHD) over an average of 6 years, among 12,433 black and white middle-aged men and women participating in the Atherosclerosis Risk in Communities (ARIC) study. OH was defined as a SBP decrease ≥ 20 mm Hg or a DBP decrease ≥ 10 mm Hg after changing from supine to standing. CHD events included definite or probable myocardial infarctions (MI), silent MI, and fatal CHD. Five percent of participants had OH. Prevalence increased with advancing age and was more common among those with cardiovascular disease (CVD)-related comorbidities and risk factors. Those with OH had an increased risk of CHD (hazard ratio [HR] = 3.49, 95% confidence interval [CI] = 2.58, 4.73). This association was attenuated after controlling for age, ethnicity, gender, comorbid conditions, and CVD risk factors (HR = 1.85, 95% CI = 1.31, 2.63).  相似文献   
93.
BackgroundStool-based DNA testing for colorectal cancer is becoming a favored alternative to existing DNA screening tests. However, current methods of analysis often become more complicated and costly with increased sensitivity. The high-resolution melting assay (HRMA) is a simple and rapid mutation scanning method with low cost and superb accuracy. In this study, we verified the accuracy of HRMA for screening KRAS/TP53 mutations in stool-isolated DNA from patients with colorectal cancer.Materials and MethodsComparing to direct DNA sequencing, the accuracy of HRMA was verified by detecting KRAS/TP53 mutations in 2 independent stages. In study stage I, both tissue and stool samples from colorectal neoplasm patients were analyzed. In study stage II, stool samples from patients with colorectal neoplasms, and normal controls in clinical screening settings were examined.ResultsIn study stage I, the HRMA identified 14 of 17 target mutations (82.4%) in stools from cancer patients, and 4 of 5 (80.0%) target mutations in stools from advanced adenoma patients. The mutation detection rate in fecal samples (45.0%; 18/40) and referred tissue samples (55.0%; 22/40) was highly consistent (κ = 0.79). The HRMA detected 1% mutant DNA in a background of wild type DNA. In study stage II, the HRMA assay detected 58.8% (20/34) mutations in tumor samples, 41.5% (17/41) in advanced adenomas samples, and 3.33% (2/60) in age-matched normal control samples. The results from HRMA and DNA sequencing revealed 100% sensitivity and specificity in both tissue and stool samples.ConclusionHRMA is a simple, reliable, and sensitive method for detecting DNA mutations in the stool samples from patients with colorectal neoplasms.  相似文献   
94.
The problem of controlling the quality of raw materials and/or final product of traditional Chinese medicine (TCM) has been studied. Earlier proposed consistency index to assess the consistency of quality of raw materials and/or final product processed or manufactured from different locations or sites has only focused on a single (i.e., the most active) component assuming that the most active component can be quantitatively identified among multiple active components. In this paper, we extend such results to the case of two correlative components. Sampling plans (sample sizes) are obtained for various combinations of study parameters. An example concerning a TCM for treating patients with rheumatoid arthritis is presented to illustrate the use of the proposed method. Some concluding remarks are also provided.  相似文献   
95.
In clinical development, an adaptive design combining results from two separate studies (e.g., a seamless adaptive design with a dose finding study phase and a confirmatory study phase) is commonly considered. The purpose of an adaptive design is not only to reduce lead time between the two studies, but also to evaluate the treatment effect in a more efficient way. In this paper, the focus is on the case where the study objectives are the same but the time durations of the study periods are different in the two stages. In particular, event data are collected in both stages. Statistical procedure for combining data observed from the two different stages is discussed. Furthermore, results on hypotheses testing and sample size calculation are derived for the comparison of two treatments.  相似文献   
96.
97.
Allele frequencies of five miniSTRs loci (D1S1656, D2S441, D12S391, D10S1248 and D22S1045) included in the new European Standard Set (ESS) were calculated from a sample of 150 unrelated individuals from Apulia, a Region of Southern Italy. Two different PCR Amplification Kits were used, in order to evaluate the concordance of the genotypes. The results obtained with the two kits showed no differences in all genotype profiles. No deviation from Hardy–Weinberg expectations was detected at either locus. Moreover genetic analysis using Fst estimation showed no evidence for differentiation at the five new loci between Apulia and Italian populations. The high levels of polymorphisms of the analyzed markers in the Apulian population allow to confirm that these markers are useful tools in paternity and forensic analysis from degraded DNA samples.  相似文献   
98.
Background and study aimsData from Japanese series show that surface morphology of laterally spreading tumors (LST) in the colon identifies lesions with different incidence and pattern of submucosal invasion. Such data from western countries are scarce. We compared clinical and histological features of LST in a western country and an eastern country, with special interest on mucosal invasiveness of LST, and investigated the effect of clinical factors on invasiveness in both countries.Patients and methodsPatients with LST lesions ≥20 mm were included from a multicenter prospective registry in Spain and from a retrospective registry from the National Cancer Center Hospital East, Japan. The primary outcome was the presence of submucosal invasion in LST. The secondary outcome was the presence of high-risk histology, defined as high-grade dysplasia or submucosal invasion.ResultsWe evaluated 1102 patients in Spain and 663 in Japan. Morphological and histological characteristics differed. The prevalence of submucosal invasion in Japan was six-fold the prevalence in Spain (Prevalence Ratio PR = 5.66; 95%CI: 3.96, 8.08), and the prevalence of high-risk histology was 1.5 higher (PR = 1.44; 95%CI: 1.31, 1.58). Compared to the granular homogeneous type and adjusted by clinical features, granular mixed, flat elevated, and pseudo-depressed types were associated with higher odds of submucosal invasion in Japan, whereas only the pseudo-depressed type showed higher risk in Spain. Regarding high-risk histology, both granular mixed and pseudo-depressed were associated with higher odds in Japan, compared with only the granular mixed type in Spain.ConclusionThis study reveals differences in location, morphology and invasiveness of LST in an eastern and a western cohort.  相似文献   
99.
AimTo determine the prevalence of endoscopic lesions unrelated with portal hypertension in patients with cirrhosis.Patients and methodsCross-sectional study including a consecutive cohort of patients with liver cirrhosis enrolled in a screening program of oesophageal varices who underwent an upper gastrointestinal endoscopy from November, 2013, to November, 2018. Clinical predictors of endoscopic lesions unrelated to portal hypertension were analyzed by univariate and multivariate logistic regression.ResultsA total of 379 patients were included. The most frequent aetiology of liver disease was alcohol consumption (60.4%). The prevalence of endoscopic lesions unrelated with portal hypertension was 39.6% (n=150). Among 96 patients with peptic lesions, urease was obtained in 56.2% of patients (positive in 44.4% of them). The prevalence of endoscopic lesions unrelated to portal hypertension was not associated with age, gender, liver function or ultrasound findings of portal hypertension. The prevalence of endoscopic lesions unrelated to portal hypertension was not associated with age, gender, liver function or ultrasound findings of portal hypertension. Smokers had a trend to increased prevalence of endoscopic lesions unrelated to portal hypertension (43.2% vs. 34.6%; p=0.09), particularly peptic ulcer (6.4% vs. 0.6%; p=0.05) and peptic duodenitis (17.3% vs. 6.3%; p=0.002). Active smoking was the only independent predictor of peptic ulcer or duodenitis (OR=2.56; p=0.017).ConclusionActive smoking is a risk factor for endoscopic lesions unrelated to portal hypertension. This finding should be further investigated to reassess endoscopic screening programs in cirrhotic smokers.  相似文献   
100.
《Vaccine》2015,33(27):3142-3149
To overcome the limiting antigenic repertoire of protein sub-units and the side effects of adjuvants applied in second generation vaccines, the present work combined in vitro and in vivo manipulations to develop biomaterials allowing natural antigen-loading and presentation in vitro and further activation of the immune response in vivo. 3-dimensional laser micro-textured implantable Si-scaffolds supported mouse macrophage adherence, allowed natural seeding with human serum albumin (antigen) and specific antibody and inflammatory cytokine production in vitro. Implantation of Si-scaffolds loaded with antigen-activated macrophages induced an inflammatory reaction along with antigen-specific antibody production in vivo, which could be detected even 30 days post implantation. Analysis of implant histology using scanning electron microscopy showed that Si-scaffolds could be stable for a 6-month period. Such technology leads to personalized implantable vaccines, opening novel areas of research and treatment.  相似文献   
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