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排序方式: 共有107条查询结果,搜索用时 15 毫秒
1.
A series of 10 3-(hetarylaminomethylene)quinolinediones, 12 3-(substituted aminopropenoyl)-4-hydroxyquinolinones, and 10 3-(substituted aminomethylene-5-oxo-pyrazolinyl)-4-hydroxyquinolinones were synthesized as novel enaminones derived from 3-(un)substituted 4-hydroxyquinolin-2(1H)-ones in 72-94% yields and assayed for their molluscicidal activities against Biomphalaria alexandrina and Lymnaea natalensis snails. Some of the tested enaminones presented high molluscicidal activities (LC(50)20ppm). The new compounds showed more potency against hatchability of B. alexandrina egg masses, the infection rate and prepatent period of the snails. In addition, these derivatives revealed potential larvicidal effects (100% mortality) on both miracidia and cercariae of Schistosoma mansoni at reduced exposure time. The selected active derivatives were examined against Daphnia magna and their nontoxic effect at all sublethal, lethal, and higher concentrations suggests that these compounds can play an important role as molluscicides and larvicides with environmental safe properties. 相似文献
2.
不同耕作措施对冬小麦-夏玉米复种连作系统土壤有机碳和水分利用效率的影响 总被引:1,自引:1,他引:1
在连续8年田间定位试验的基础上,分析了关中平原冬小麦 夏玉米复种连作系统2008—2009年连续两个生长季期间不同耕作措施(结合秸秆还田和不还田)对土壤有机碳和水分利用率的影响.结果表明: 相对于传统耕作,保护性耕作有利于土壤有机碳、水分利用效率和作物产量的提高,其中在“深松+秸秆还田”耕作模式下的增幅最高,土壤有机碳含量在0~30 cm土层增幅达到19.5%,水分利用效率和作物产量提高了16.9%和20.5%,而免耕模式则有效提高了0~10 cm土层有机碳含量.在该地区土壤和气候条件下,深松结合秸秆粉碎还田是最理想的耕作模式,最有利于土壤有机碳累积,并提高水分利用效率和作物产量. 相似文献
3.
Parvaiz Ahmad Mohammad Abass Ahanger Mohammed Nasser Alyemeni Leonard Wijaya Pravej Alam Mohammad Ashraf 《Journal of Plant Interactions》2018,13(1):64-72
We investigated the effects of exogenous application of jasmonic acid (JA) and nitric oxide (NO) on growth, antioxidant metabolism, physio-biochemical attributes and metabolite accumulation, in tomato (Solanum lycopersicum L.) plants exposed to salt stress. Treating the plants with NaCl (200 mM) resulted in considerable growth inhibition in terms of biomass, relative water content, and chlorophyll content, all of which were significantly improved upon application of JA and NO under both normal and NaCl-stress treatments. Salt treatment particularly 200 mM NaCl caused an apparent increase in electrolyte leakage, lipid peroxidation, and hydrogen peroxide production, which were reduced by exogenous application of JA and NO. Salt treatment triggered the induction of antioxidant system by enhancing the activities of antioxidant enzymes like superoxide dismutase (SOD), catalase (CAT), ascorbate peroxidase (APX), and glutathione reductase (GR). Application of JA and NO separately as well as in combination caused a significant improvement in activities of SOD, CAT, APX, and GR activities. JA and NO either applied individually or in combination boosted the flavonoid, proline and glycine betaine synthesis under NaCl treatments. In conclusion, the exogenous application of JA and NO protected tomato plants from NaCl-induced damage by up-regulating the antioxidant metabolism, osmolyte synthesis, and metabolite accumulation. 相似文献
4.
Factors Affecting Women's Autonomous Decision Making In Research Participation Amongst Yoruba Women Of Western Nigeria 下载免费PDF全文
Chitu Womehoma Princewill Ayodele S. Jegede Karin Nordström Bolatito Lanre‐Abass Bernice Simone Elger 《Developing world bioethics》2017,17(1):40-49
Research is a global enterprise requiring participation of both genders for generalizable knowledge; advancement of science and evidence based medical treatment. Participation of women in research is necessary to reduce the current bias that most empirical evidence is obtained from studies with men to inform health care and related policy interventions. Various factors are assumed to limit autonomy amongst the Yoruba women of western Nigeria. This paper seeks to explore the experience and understanding of autonomy by the Yoruba women in relation to research participation. Focus is on factors that affect women's autonomous decision making in research participation. An exploratory qualitative approach comprising four focus group discussions, 42 in‐depth interviews and 14 key informant interviews was used. The study permits a significant amount of triangulation, as opinions of husbands and religious leaders are also explored. Interviews and discussions were audiotaped and transcribed verbatim. Content analysis was employed for data analysis. Findings show that concepts of autonomy varied amongst the Yoruba women. Patriarchy, religion and culture are conceived to have negative impact on the autonomy of women in respect to research participation. Among the important findings are: 1) male dominance is strongly emphasized by religious leaders who should teach equality, 2) while men feel that by making decisions for women, they are protecting them, the women on the other hand see this protection as a way of limiting their autonomy. We recommend further studies to develop culturally appropriate and workable recruitment methods to increase women's participation in research. 相似文献
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K Michałek M Laszczyńska AK Ciechanowicz A Herosimczyk I Rotter M Oganowska 《Biotechnic & histochemistry》2014,89(5):342-347
Aquaporin 2 (AQP2) is a small, integral tetrameric plasma membrane protein that is expressed in mammalian kidneys. The specific constitution of this protein and its selective permeability to water means that AQP2 plays an important role in hypertonic urine production. Immunolocalization of AQP2 has been studied in humans, monkeys, sheep, dogs, rabbits, rats, mice and adult cattle. We analyzed the expression of AQP2 in kidneys of 7-month-old Polish-Friesian var. black and white male calves. AQP2 was localized in the principal cells of collecting ducts in medullary rays penetrating the renal cortex and in the collecting ducts of renal medulla. AQP2 was expressed most strongly in the apical plasma membrane, but expression was observed also in the intracellular vesicles and basolateral plasma membrane. Our study provides new information concerning the immunolocalization of AQP2 in calf kidneys. 相似文献
8.
In the current study we aimed to execute a rather less complicated molecular tying method, i.e. the random amplification of polymorphic DNA (RAPD) analysis to find the heterogeneity of Iranian strains of Mycobacterium tuberculosis. The isolates comprised a total of 96 strains of M. tuberculosis collected from clinical specimens of patients in Isfahan and Tehran. The isolates were assigned to the species M. tuberculosis by the key conventional and molecular methods. They were then subjected to RAPD analysis by four arbitrary primers, namely, the primers 27F, 1525R, MS- GF and INS-2. They were then evaluated for the number and intensity of the band patterns. The RAPD profiles of the Iranian isolates showed a degree of heterogeneity which varied based on the primer used. However, analysis of the isolates by primer INS-2 revealed the highest degree of diversity yielding 31 distinguishable RAPD types. RAPD analysis provides a rapid and easy means of identifying heterogeneity among the M. tuberculosis isolates. This typing system might be considered a valuable alternative molecular typing for countries with limited resources provided that the reproducibility and reliability of the method is carefully assured. 相似文献
9.
Mehta NN Torigian DA Gelfand JM Saboury B Alavi A 《Journal of visualized experiments : JoVE》2012,(63):e3777
Conventional non-invasive imaging modalities of atherosclerosis such as coronary artery calcium (CAC) and carotid intimal medial thickness (C-IMT) provide information about the burden of disease. However, despite multiple validation studies of CAC, and C-IMT, these modalities do not accurately assess plaque characteristics, and the composition and inflammatory state of the plaque determine its stability and, therefore, the risk of clinical events. [(18)F]-2-fluoro-2-deoxy-D-glucose (FDG) imaging using positron-emission tomography (PET)/computed tomography (CT) has been extensively studied in oncologic metabolism. Studies using animal models and immunohistochemistry in humans show that FDG-PET/CT is exquisitely sensitive for detecting macrophage activity, an important source of cellular inflammation in vessel walls. More recently, we and others have shown that FDG-PET/CT enables highly precise, novel measurements of inflammatory activity of activity of atherosclerotic plaques in large and medium-sized arteries. FDG-PET/CT studies have many advantages over other imaging modalities: 1) high contrast resolution; 2) quantification of plaque volume and metabolic activity allowing for multi-modal atherosclerotic plaque quantification; 3) dynamic, real-time, in vivo imaging; 4) minimal operator dependence. Finally, vascular inflammation detected by FDG-PET/CT has been shown to predict cardiovascular (CV) events independent of traditional risk factors and is also highly associated with overall burden of atherosclerosis. Plaque activity by FDG-PET/CT is modulated by known beneficial CV interventions such as short term (12 week) statin therapy as well as longer term therapeutic lifestyle changes (16 months). The current methodology for quantification of FDG uptake in atherosclerotic plaque involves measurement of the standardized uptake value (SUV) of an artery of interest and of the venous blood pool in order to calculate a target to background ratio (TBR), which is calculated by dividing the arterial SUV by the venous blood pool SUV. This method has shown to represent a stable, reproducible phenotype over time, has a high sensitivity for detection of vascular inflammation, and also has high inter-and intra-reader reliability. Here we present our methodology for patient preparation, image acquisition, and quantification of atherosclerotic plaque activity and vascular inflammation using SUV, TBR, and a global parameter called the metabolic volumetric product (MVP). These approaches may be applied to assess vascular inflammation in various study samples of interest in a consistent fashion as we have shown in several prior publications. 相似文献
10.
Shi Yu Tillmann Falck Anneleen Daemen Leon-Charles Tranchevent Johan AK Suykens Bart De Moor Yves Moreau 《BMC bioinformatics》2010,11(1):309