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排序方式: 共有1324条查询结果,搜索用时 31 毫秒
1.
Danut Vai
iukynien Aras Kantautas Simona Tu
kut Fallon Manhanga Eugenijus Janavi
ius Ernestas Ivanauskas
ymantas Rudionis Aloyzas Gaudutis 《Materials》2021,14(10)
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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Vascular Endothelial Growth Factor Expression and Cyclosporine Toxicity in Renal Allograft Rejection 总被引:3,自引:0,他引:3
B. Handan Özdemir F. Nurhan Özdemir Nihan Haberal Remzi Emiroglu Beyhan Demirhan Mehmet Haberal 《American journal of transplantation》2005,5(4):766-774
The aim of this study was to evaluate the influence of vascular endothelial growth factor (VEGF) on renal function and on development of interstitial fibrosis (IF) in renal allografts. Tubular and interstitial expressions of VEGF and TNF-α, and density of macrophages in the interstitium were examined in 92 patients with nonrejected kidneys, acute rejection (AR), chronic allograft nephropathy (CAN), borderline changes (BC) and acute cyclosporin A (CsA) toxicity. Follow-up biopsy specimens from patients with AR and BC were evaluated for development of IF. A significant difference in tubular and interstitial VEGF expressions was found between patients with AR, BC, CAN and CsA toxicity (p < 0.001). Macrophage infiltration was positively correlated with VEGF and TNF-α expressions (p < 0.001). VEGF expression increased with increasing expression of TNF-α (p < 0.001). Renal function in first 6 months after initial biopsy was better in patients with marked tubular VEGF expression (p < 0.01); however, in follow-up, development of IF and graft loss was found earlier in these patients (p < 0.01 and p < 0.05, respectively). Increased renal VEGF expression has protective properties immediately following renal allograft but allows for increased risk of early IF, and therefore poor graft outcome in the long term. 相似文献
4.
Analysis of magnesium and trace elements in urinary calculi by atomic absorption spectrophotometry 总被引:1,自引:0,他引:1
Magnesium and trace element determinations in 29 urinary tract calculi were carried out using an atomic absorption spectrophotometric method. Of the calculi examined, 9 were pure calcium oxalate, 5 were mixed calcium oxalate/uric acid, 5 were mixed calcium oxalate/phosphate, 5 were magnesium ammonium phosphate and 5 were pure cystine. The measurement of magnesium and trace element levels has been considered useful in the elucidation of the mechanism of stone formation and the evaluation of factors leading to pathological consequences. In this study, the Mg, Zn, Cu, Fe, Cd and Pb content in all of the samples was determined and an attempt was made to compare the levels of these elements in calculi with the levels in normal hair. 相似文献
5.
Dr. Bektaş Açikgöz Mehmet Turgut Osman Ekin Özcan Tunçalp Özgen Beyhan Demirhan Şevket Ruacan 《Lasers in medical science》1992,7(1-4):49-53
In this study we have investigated the negative influence of CO2 and Nd-YAG laser irradiation on rapid cranial regeneration and whether it has any use in certain types of craniosynostosis.
Twenty-two newborn rats were used in the study. Both CO2 and Nd-YAG laser irradiation, which was applied to free bony edges after, suturectomies, resulted in a significant decrease
in skull regeneration. Histopathological examinations revealed severe degeneration caused by both types of laser energies. 相似文献
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Kerr AR Irvine JJ Search JJ Gingles NA Kadioglu A Andrew PW McPheat WL Booth CG Mitchell TJ 《Infection and immunity》2002,70(3):1547-1557
Variations in the host response during pneumonia caused by Streptococcus pneumoniae in susceptible (CBA/Ca) and resistant (BALB/c) inbred mouse strains were investigated. Significant differences were detected in survival time, core body temperature, lung-associated and systemic bacterial loads, mast cell numbers, magnitude and location of cytokine production, lung disruption, and ability of isolated lung cells to release the cytokine tumor necrosis factor (TNF) alpha in vitro. Overall, the results indicate that the reduced capacity of CBA/Ca mice to induce rapid TNF activity within the airways following infection with S. pneumoniae may be a factor in their elevated susceptibility to pneumococcal pneumonia. 相似文献
8.
Biochemical profile of blood serum of siraz <Emphasis Type="Italic">Capoeta capoeta umbla</Emphasis>
Abdulkadir Bayir A. Necdet Sirkecioğlu Harun Polat N. Mevlüt Aras 《Comparative clinical pathology》2007,16(2):119-126
Seasonal changes in blood plasma biochemistry of siraz Capoeta capoeta umbla were determined throughout 1 year. In the present study, while the highest values for glucose and globulin were found in
winter, the values for increased activities of total protein, albumin, calcium, sodium levels, albumin/globulin ratio, lactate
dehydrogenase, and alkaline phosphatase were determined in summer. We determined that blood biochemistry values of siraz,
which were positively affected by water temperature and pH, except glucose and globulin. Glucose and globulin were negatively
affected by water temperature and pH. Consequently, it was concluded that the seasons are key factors when blood parameters
are used as biomarkers for environmental alterations. It is difficult to define the most important factors affecting seasonal
changes of blood biochemistry in fish. 相似文献
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Jordan C. Best BS Taylor Kohn MD Premal Patel MD Ruben Blachman-Braun MD Elaine de Quadros PhD Zeki Beyhan PhD Michael Jacobs MD Ranjith Ramasamy MD 《Andrologia》2021,53(7):e14094
In this study, we sought to determine whether sperm DNA fragmentation (DFI%) and high DNA stainability (HDS%) evaluated by sperm chromatin structure assay (SCSA) predict recurrent implantation failure (RIF) or pregnancy rate. A retrospective study was performed of consecutive cycles of ICSI treatment from 2009 to 2018. A total of 386 couples that underwent 1,216 frozen embryo transfer (FET) cycles were analysed. Mean female and male age was 34 ± 3.6 years and 37.3 ± 6.6 years, respectively, and a median total motile sperm count (TMSC) was 43.5 [9.9–105.5] million. Overall median DFI% and HDS% was 12 [7.1–18.9] and 9.6 [6.5–14.4] respectively. On multivariable analysis, DFI% and HDS% were not associated with RIF (DFI%: OR = 1.01, 95% CI: 0.98–1.04, p = .414; HDS%: OR = 0.97, 95% CI: 0.94–1.01, p = .107) or IVF success, defined as clinical pregnancy (DFI%: OR = 1.00, 95% CI: 0.99–1.01, p = .641; HDS%: OR = 1.01, 95% CI: 0.99–1.02, p = .565). We found that neither DFI% or HDS%, as assessed by SCSA, were predictive of RIF or pregnancy rate. This finding suggests that sperm DNA fragmentation does not predict RIF or pregnancy rate. 相似文献