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1.
Concrete plants accumulate large amounts of concrete wash water. This water, which pH is highly alkaline, has a negative impact on the environment. Its reuse in fresh concrete slightly reduces its mechanical properties. The combination of concrete wash water and zeolitic by-product led to an increase of 4.6% in the compressive strength at 7 days hydration and up to 30% at 28 days hydration. The same combination led to the denser microstructure compared to the samples made with concrete wash water. This could be explained by the pozzolanic reaction of the zeolitic by-product. The complex chemical reactions of cement, zeolitic by-product, and fines presented in the concrete wash water occurred. Therefore, it was suggested the reusing method of concrete wash water together with zeolitic by-product in the fresh concrete mixtures by substituting some amount of tap water with concrete wash water. In this way, the consumption of tap water is possible to reduce in cement systems.  相似文献   
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Human leukocyte antigen (HLA) compatibility has no clinically significant impact in cadaveric liver transplantation. Less is known regarding living-donor liver transplantation (LDLT). Our prior analysis of the Organ Procurement and Transplantation Network (OPTN) database suggested a higher graft failure rate in patients who underwent LDLT from donors with close HLA match. We further investigated the effect of HLA-A, -B, and -DR matching on 5-yr graft survival in adult LDLT by analyzing OPTN data regarding adult LDLT performed between 1998 and 2005. We evaluated associations between 5-yr graft survival and total, locus-specific, and haplotype match levels. Separate analyses were conducted for recipients with autoimmune (fulminant autoimmune hepatitis, cirrhosis secondary to autoimmune hepatitis, primary biliary cirrhosis, primary sclerosing cholangitis) or nonautoimmune liver disease. Multivariable Cox proportional hazard models were used to evaluate interactions and adjust for potential confounders. Among 631 patients with available donor/recipient HLA data, the degree of HLA match had no significant effect on 5-yr graft survival, even when analyzed separately in recipients with autoimmune vs. nonautoimmune liver disease. To be able to include all 1,838 adult LDLTs, we considered a first-degree related donor as substitute for a close HLA match. We found no difference in graft survival in related vs. unrelated pairs. In conclusion, our results show no detrimental impact of close HLA matching on graft survival in adult LDLT, including in recipients with underlying autoimmune liver disease.  相似文献   
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BACKGROUND: The HOXA1 gene plays a major role in brainstem and cranial morphogenesis. The G allele of the HOXA1 A218G polymorphism has been previously found associated with autism. METHODS: We performed case-control and family-based association analyses, contrasting 127 autistic patients with 174 ethnically matched controls, and assessing for allelic transmission disequilibrium in 189 complete trios. RESULTS: A, and not G, alleles were associated with autism using both case-control (chi(2) = 8.96 and 5.71, 1 df, p <.005 and <.025 for genotypes and alleles, respectively), and family-based (transmission/disequilibrium test chi(2) = 8.80, 1 df, p <.005) association analyses. The head circumference of 31 patients carrying one or two copies of the G allele displayed significantly larger median values (95.0th vs. 82.5th percentile, p <.05) and dramatically reduced interindividual variability (p <.0001), compared with 166 patients carrying the A/A genotype. CONCLUSIONS: The HOXA1 A218G polymorphism explains approximately 5% of the variance in the head circumference of autistic patients and represents to our knowledge the first known gene variant providing sizable contributions to cranial morphology. The disease specificity of this finding is currently being investigated. Nonreplications in genetic linkage/association studies could partly stem from the dyshomogeneous distribution of an endophenotype morphologically defined by cranial circumference.  相似文献   
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Ocotea quixos essential oil was shown to possess significant inhibitory activity of platelet aggregation and clot retraction in rodent plasma. This study is aimed at fully characterizing the antiplatelet activity of the whole essential oil and its main components trans-cinnamaldehyde and methyl cinnamate also in human plasma, at investigating the mechanism underlying such activity and at evaluating the potential antithrombotic activity of subacute treatment of mice with Ocotea essential oil. In vitro Ocotea essential oil and trans-cinnamaldehyde inhibited arachidonic acid-, U46619-, ADP-, phorbol12-myristate13-alcetate-, collagen-induced platelet aggregation and thrombin-induced clot retraction in human and rodent plasma; Ocotea oil and trans-cinnamaldehyde competitively antagonized contractions induced by thromboxane A2 receptor agonist U46619 in rat isolated aortic ring (K(B) = 18 and 3.2 microg ml(-1), respectively). In vivo Ocotea oil, orally administered in a subacute treatment (30-100 mg kg(-1) day(-1) for 5 days) to mice, prevented acute thrombosis induced by collagen-epinephrine intravenous injection. This antithrombotic activity was not accompanied by pro-haemorragic side effect, as detected by the inactivity in bleeding test, thus showing a favourable safety profile compared to the conventional antiplatelet agent, acetylsalicylic acid. Present findings indicate that Ocotea essential oil possesses potent and safe antithrombotic activity attributable to its antiplatelet and vasorelaxant effects. The main constituent trans-cinnamaldehyde seems to be the primary responsible for this activity through a putative mechanism involving the inhibition of thromboxane A2 receptors.  相似文献   
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采用SD大鼠一侧大脑中动脉阻断致局限性脑缺血模型。脑缺血后迅速断头置于液氮中,HPLC外标定量法测定各磷脂组分。观察脑缺血1、5、15、60、360min时脑细胞膜磷脂含量变化。结果显示,PI在缺血早期显著低于对照组(P<0.01~0.05);PE、PC早期仅呈下降趋势,PE在缺血60min组、PC缺血360min组显著低于对照组(P<0.01~0.05)。PS在缺血全过程中变化轻微(P>0.05)。提示磷脂降解与脑缺血存在一定关系,缺血早期首先出现脑细胞膜功能磷脂降解,膜结构磷脂则在缺血后期出现显著变化,且PE较PC优先降解。  相似文献   
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BACKGROUND: Fluorine 18 fluorodeoxyglucose (FDG) uptake may be increased in atherosclerotic plaques in asymptomatic patients. Repeat positron emission tomography (PET)/computed tomography (CT) studies were assessed for changes in patterns of FDG uptake and CT calcifications. METHODS AND RESULTS: Fifty consecutive cancer patients (mean age, 68 +/- 8 years) had repeat PET/CT studies 8 to 26 months apart. PET, CT, and PET/CT images were retrospectively evaluated for vascular wall abnormalities and for interval changes in the thoracic and abdominal aortas, as well as in carotid and iliac arteries, classified as PET+/CT+, PET+/CT-, and PET-/CT+. There were 485 abnormal sites in the first study and 495 in the second. CT calcifications were found in 46 patients (92%) in the first study and in 47 (94%) in the second. Vascular wall FDG uptake was found in both studies in 37 patients (74%). The pattern changed in 57 of 119 PET+ sites (48%) in the second study compared with 15 of 366 PET- sites (4%) (P < .0001). In the second study new PET+ sites were observed in 36 of 111 sites (32%) versus new PET-/CT+ sites in 19 of 384 sites (5%) (P < .0001). CONCLUSIONS: Changes in vascular FDG activity and CT calcifications can be assessed by repeat PET/CT. FDG-avid foci may represent a dynamic process, transient inflammation, whereas CT calcifications may indicate stable atherosclerosis. These preliminary results support the need for further research.  相似文献   
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Human immunodeficiency virus (HIV)-associated progressive multifocal leukoencephalopathy (PML) remains a relevant clinical problem even in the era of highly active antiretroviral therapy (HAART). Aims of the study were to analyze clinical and treatment-related features and the survival probability of PML patients observed within the Italian Registry Investigative Neuro AIDS (IRINA) during a 29-month period of HAART. Intravenous drug use, the presence of focal signs, and the involvement of white matter at neuroradiology increased the risk of having PML. A reduced probability of PML was observed when meningeal signs were reported. Patients starting HAART at PML diagnosis and previously naïve for antiretrovirals showed significantly higher 1-year probability of survival (.58), compared to those continuing HAART (.24), or never receiving HAART (.00). Higher CD4 cell count were associated with a higher survival probability (.45). At multivariate analysis, a younger age, higher CD4, starting HAART at PML diagnosis, the absence of previous acquired immunodeficiency syndrome (AIDS)-defining events, and the absence of a severe neurologic impairment were all associated with a reduced hazard of death. The use of cidofovir showed a trend towards a reduced risk of death.  相似文献   
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