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排序方式: 共有331条查询结果,搜索用时 15 毫秒
321.
Noreen Akhter Muhammad Aqeel Muhammad Muslim Shahnaz Ghalia S. H. Alnusairi Suliman Mohammed Alghanem Abida Kousar Mohamed Hashem Hina Kanwal Saad Alamri Aisha Ilyas Omar Mahmoud Al-zoubi Ali Noman 《Physiology and Molecular Biology of Plants》2021,27(4):687
The natural capacity of plants to endure salt stress is largely regulated by multifaceted structural and physio-biochemical modulations. Salt toxicity endurance mechanism of six ecotypes of Typha domingensis Pers. was evaluated by analyzing photosynthesis, ionic homeostasis, and stomatal physiology under different levels of salinity (0, 100, 200 and 300 mM NaCl). Typha populations were collected across different areas of Punjab, an eastern province in Pakistan. All studied attributes among ecotypes presented differential changes as compared to control. Different salt treatments not only affected gas exchange attributes but also shown significant modifications in stomatal anatomical changes. As compared to control, net photosynthetic rate, transpiration rate, total chlorophyll contents and carotenoids were increased by 111%, 64%, 103% and 171% respectively, in Sahianwala ecotype among all other ecotypes. Similarly, maximum water use efficiency (WUE), sub stomatal CO2 concentration, sodium (Na+) and chloride (Cl−) contents were observed in Sahianwala (191%, 93%, 168%, 158%) and Knotti (162%, 75%, 146%, 182%) respectively, as compared to the others ecotypes. Adaxial and abaxial stomatal areas remained stable in Sahianwala and Knotti. The highest abaxial stomatal density was observed in Gatwala ecotype (42 mm2) and maximum adaxial stomatal density was recorded in Sahianwala ecotype (43 mm2) at 300 mM NaCl salinity. The current study showed that Typha ecotypes responded varyingly to salinity in terms of photosynthesis attributes to avoid damages due to salinity. Overall, differential photosynthetic activity, WUE, and changes in stomatal attributes of Sahianwala and Knotti ecotypes contributed more prominently in tolerating salinity stress. Therefore, Typha domingensis is a potential species to be used to rehabilitate salt affected lands for agriculture and aquatic habitat.Supplementary InformationThe online version contains supplementary material available at 10.1007/s12298-021-00963-x. 相似文献
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Curvularia lunata IM 2901, the filamentous fungus used for hydrocortisone manufacture, was found to be able to produce an extracellular emulsifying agent on water-soluble compounds with a yield of 2.6 g l(-1). Cell-free culture broth containing the examined agent caused the formation of stable emulsions with hydrophobic compounds of natural and xenobiotic origin. Vegetable and mineral oils were the best substrates for emulsification. Kinetics of surfactant biosynthesis was classified as a mixed growth-associated and non-growth-associated type. The crude emulsifier was isolated from culture fluid by acetone precipitation. Preliminary chemical characterization showed that the studied bioemulsifier contained 34.0% C, 5.7% H, 1.8% N, 0.15% S and was a complex of protein (25%) and polysaccharide (48%). Sugar component was identified as a polymer of D-glucose. 相似文献
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ABSTRACT: BACKGROUND: Thalassemia is a blood disorder passed down through families (inherited) in which the body makes an abnormal form of hemoglobin. This disorder results in excessive destruction of red blood cells, and there is no effective treatment. Patients require lifelong blood transfusion, usually started within 6 to 12 months of birth of patient, which on other hand has its own complications. It is a chronic disease that manifests so early in life that it leads to psychological and social problems for parents . We focused on parents to assess the impact of their child's disease. OBJECTIVE: To determine the psychosocial problems of parents of thalassemic children. METHODS: This cross sectional study was conducted among the parents of thalassemic children attending THALASSEMIA CENTRE, BAHAVAL VICTORIA HOSPITAL (BVH), BAHAWALPUR, PAKISTAN during the year 2011. A self designed questionnaire was used that contained questions regarding psychological and social aspects. Patient Health Questionnaire-9 (PHQ- 9) was used to assess the depression of parents of thalassemic children. RESULTS: Of the 100 parents interviewed, the majority were mothers (71%), with a mean age of 32 +/- 8.07 years for both sexes. 29 percent of the parents had moderate to severe depression, 16 percent had sleep disturbances. 56 percent were downgraded by relatives. There was a significant relationship between respondent education and depression(p < 0.05). CONCLUSION: A substantial number of parents have psychosocial problems due to the disease of their child. Parent counseling is needed on regular basis. 相似文献
326.
Giorgio Luigi Valentini Walter Lassonde Samee Ullah Khan Nasro Min-Allah Sajjad A. Madani Juan Li Limin Zhang Lizhe Wang Nasir Ghani Joanna Kolodziej Hongxiang Li Albert Y. Zomaya Cheng-Zhong Xu Pavan Balaji Abhinav Vishnu Fredric Pinel Johnatan E. Pecero Dzmitry Kliazovich Pascal Bouvry 《Cluster computing》2013,16(1):3-15
Two major constraints demand more consideration for energy efficiency in cluster computing: (a) operational costs, and (b) system reliability. Increasing energy efficiency in cluster systems will reduce energy consumption, excess heat, lower operational costs, and improve system reliability. Based on the energy-power relationship, and the fact that energy consumption can be reduced with strategic power management, we focus in this survey on the characteristic of two main power management technologies: (a) static power management (SPM) systems that utilize low-power components to save the energy, and (b) dynamic power management (DPM) systems that utilize software and power-scalable components to optimize the energy consumption. We present the current state of the art in both of the SPM and DPM techniques, citing representative examples. The survey is concluded with a brief discussion and some assumptions about the possible future directions that could be explored to improve the energy efficiency in cluster computing. 相似文献
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Sadia Perveen Hanfa Ashfaq Saira Ambreen Isbah Ashfaq Zakia Kanwal Asima Tayyeb 《Saudi Journal of Biological Sciences》2021,28(1):879
Breast cancer is a major cause of cancer related deaths in women worldwide. Available treatments pose serious limitations such as systemic toxicity, metastasis, tumor recurrence, off-target effects, and drug resistance. In recent years, phytochemicals such as secondary metabolites due to their effective anticancer potential at very low concentration have gained attention. Aim of the study was to evaluate anticancer potential of Citrullus colocynthis and its possible molecular targets on MCF-7, a human breast cancer cell line. Methanolic extract of leaves was prepared and fractionated by solvents (n-hexane, chloroform, ethyl acetate and n-butanol) with increasing polarity. Bioassays and gene expression regulation was conducted to evaluate the anticancer activity, proliferation rate and cell cycle regulation of breast cancer cells treated with extract and its fractions, separately. Results showed a significant anticancer activity of methanolic extract of C. colocynthis and two of its fractions prepared with chloroform and ethyl acetate. Bioassays depicted significant decrease in proliferation and growth potential along with cell cycle arrest of treated cells compared to control untreated cells. Expression regulation of genes further confirmed the cell cycle arrest through significant upregulation of cyclin-CDK inhibitors (p21 and p27) and cell cycle checkpoint regulators (HUS1, RAD1, ATM) followed by downregulation of downstream cell cycle progression genes (Cyclin A, Cyclin E, CDK2). It is concluded that C. colocynthis arrests cell cycle in human breast cancer cells through expression regulation of cyclin-CDK inhibitors and with further research can be proposed for therapeutic interventions. 相似文献
329.
Saini Abhinav Chandra Kumari Binita Kumar Vikrant Mathur Sandeep R Sharma J B Kumar Sunesh Yadav Savita 《Molecular biology reports》2020,47(12):9459-9468
Molecular Biology Reports - Ovarian cancer, the most lethal gynecological cancer, is the fifth most common cause of cancer-related deaths in women. A cost-effective and non-invasive early screening... 相似文献
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