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排序方式: 共有660条查询结果,搜索用时 15 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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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
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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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Direct trocar insertion versus Veress needle insertion in laparoscopic cholecystectomy 总被引:5,自引:0,他引:5
Yerdel MA Karayalcin K Koyuncu A Akin B Koksoy C Turkcapar AG Erverdi N Alaçayir I Bumin C Aras N 《American journal of surgery》1999,177(3):247-249
BACKGROUND: Direct insertion of the trocar is an alternative method to Veress needle insertion for the creation of pneumoperitoneum. The safety of direct disposable shielded trocar insertion for the creation of pneumoperitoneum was assessed by comparing with Veress needle insertion during laparoscopic cholecystectomy (LC). METHODS: One thousand five hundred patients undergoing LC with pneumoperitoneum were included in this study. In 470 patients the Veress needle insertion technique was used, and in 1,030 patients direct trocar insertion technique was used. Patients having indications for open trocar insertion were excluded from the study. RESULTS: Complication rate was significantly higher in the Veress needle group (14% versus 0.9%; P <0.01), and the two major complications, gastric perforation and iliac artery laceration, were also encountered in this group. CONCLUSIONS: Our results suggest that with a lower complication rate, direct insertion of the disposable trocar is a safe alternative to Veress needle insertion technique for the creation of pneumoperitoneum. Such an approach has further advantages such as less cost/instrumentation and rapid creation of pneumoperitoneum. 相似文献
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Ila Datar Xiaoliang Qiu Hong Zhi Ma Miranda Yeung Shweta Aras Ivana de la Serna Fahd Al-Mulla Jean Paul Thiery Robert Trumbly Xuan Fan Hongjuan Cui Kam C. Yeung 《Oncotarget》2015,6(36):39050-39061
Accumulating evidence suggests that presence of macrophages in the tumor microenvironment add to the invasive and tumor-promoting hallmarks of cancer cells by secreting angiogenic and growth factors. RKIP is a known metastasis suppressor and interferes with several steps of metastasis. However, the mechanistic underpinnings of its function as a broad metastasis suppressor remain poorly understood. Here, we establish a novel pathway for RKIP regulation of metastasis inhibition through the negative regulation of RANTES/CCL5 thereby limiting tumor macrophage infiltration and inhibition of angiogenesis. Using a combination of loss- and gain-of-function approaches, we show that RKIP hinders breast cancer cell invasion by inhibiting expression of the CC chemokine CCL5 in vitro. We also show that the expression levels of RKIP and CCL5 are inversely correlated among clinical human breast cancer samples. Using a mouse allograft breast cancer transplantation model, we highlight that ectopic expression of RKIP significantly decreases tumor vasculature, macrophage infiltration and lung metastases. Mechanistically, we demonstrate that the inhibition of the CCL5 expression is the cause of the observed effects resulting from RKIP expression. Taken together, our results underscore the significance of RKIP as important negative regulator of tumor microenvironment. 相似文献
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