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排序方式: 共有3904条查询结果,搜索用时 31 毫秒
1.
Raza Shahbaz Mohsin Mashkoor Madni Waqas Ahmed Sarwar Fatima Saqib Muhammad Aslam Bilal 《EcoHealth》2017,14(1):182-186
EcoHealth - We investigated wild migratory birds faecal swabs for extended-spectrum β-lactamases-producing Klebsiella pneumoniae (ESBL-K. pneumoniae) from wetland habitats in Pakistan. ESBL-K.... 相似文献
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Structural Insight of a Trimodular Halophilic Cellulase with a Family 46 Carbohydrate-Binding Module
Huaidong Zhang Guimin Zhang Chaoxiang Yao Muhammad Junaid Zhenghui Lu Houjin Zhang Yanhe Ma 《PloS one》2015,10(11)
Cellulases are the key enzymes used in the biofuel industry. A typical cellulase contains a catalytic domain connected to a carbohydrate-binding module (CBM) through a flexible linker. Here we report the structure of an atypical trimodular cellulase which harbors a catalytic domain, a CBM46 domain and a rigid CBM_X domain between them. The catalytic domain shows the features of GH5 family, while the CBM46 domain has a sandwich-like structure. The catalytic domain and the CBM46 domain form an extended substrate binding cleft, within which several tryptophan residues are well exposed. Mutagenesis assays indicate that these residues are essential for the enzymatic activities. Gel affinity electrophoresis shows that these tryptophan residues are involved in the polysaccharide substrate binding. Also, electrostatic potential analysis indicates that almost the entire solvent accessible surface of CelB is negatively charged, which is consistent with the halophilic nature of this enzyme. 相似文献
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Muhammad Yaseen Muhammad Zahir Aziz Abdul Aleem Jafar Muhammad Naveed 《International journal of phytoremediation》2016,18(5):502-508
A field experiment in collaboration with a private textile industry (Noor Fatima Fabrics Private (Ltd.), Faisalabad) was conducted to evaluate the effect of disposed water from bleaching unit, printing unit and end drain for improving growth and yield of wheat under saline sodic soil. Textile waste water along with canal water (control) was applied with and without liquid NPK fertilizer. The application of liquid NPK fertilizer with end drain waste water increased plant height, spike length, flag leaf length, root length, number of tillers (m?2), number of fertile tillers (m?2), 1000 grain weight, grain yield, straw yield and biological yield up to 21, 20, 20, 44, 17, 20, 14, 44, 40 and 41%, respectively compared to canal water (control). Similarly, the NPK uptake in grain was increased up to 15, 30 and 28%, respectively by liquid fertilizer treated end drain water as compare to canal water with liquid fertilizer. Moreover, concentration of different heavy metals particularly Cu, Cr, Pb and Cd was decreased in grains by application of waste water along with liquid NPK. The result may imply that waste water application along with liquid-NPK could be a novel approach for improving growth and yield of wheat in saline sodic soils. 相似文献
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Perspective texture synthesis has great significance in many fields like video editing, scene capturing etc., due to its ability to read and control global feature information. In this paper, we present a novel example-based, specifically energy optimization-based algorithm, to synthesize perspective textures. Energy optimization technique is a pixel-based approach, so it’s time-consuming. We improve it from two aspects with the purpose of achieving faster synthesis and high quality. Firstly, we change this pixel-based technique by replacing the pixel computation with a little patch. Secondly, we present a novel technique to accelerate searching nearest neighborhoods in energy optimization. Using k- means clustering technique to build a search tree to accelerate the search. Hence, we make use of principal component analysis (PCA) technique to reduce dimensions of input vectors. The high quality results prove that our approach is feasible. Besides, our proposed algorithm needs shorter time relative to other similar methods. 相似文献
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Amjad Islam Jianguo Li Muhammad Pervaiz Zheng‐Hong Lu Mohini Sain Lihui Chen Xinhua Ouyang 《Liver Transplantation》2019,9(10)
Zwitterions, a class of materials that contain covalently bonded cations and anions, have been extensively studied in the past decades owing to their special features, such as excellent solubility in polar solvents, for solution processing and dipole formation for the transfer of carriers and ions. Recently, zwitterions have been developed as electrode modifiers for organic solar cells (OSCs), perovskite solar cells (PVSCs), and organic light‐emitting devices (OLEDs), as well as electrolyte additives for lithium ion batteries (LIBs). With the rapid advances of zwitterionic materials, high‐performance devices have been constructed with enhanced efficiencies by introducing them as interface layers and electrolyte additives. In this review, recent progress in OSCs, PVSCs, OLEDs, and LIBs by using zwitterions is highlighted. The authors also elaborate the role of various zwitterionic materials as interfacial layers and additives for highly efficient OSCs, PVSCs, OLEDs, and LIBs. This article presents an overview of device performance of zwitterionic materials. The structure–property relationship is also discussed. Finally, the prospects of zwitterion materials are also addressed. 相似文献
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Muhammad A.H. Gali David I. de Pomerai 《Differentiation; research in biological diversity》1984,25(1-3):238-246
Abstract. Three different culture media, Ham's F-12, medium 199, and Eagle's minimal essential medium (MEM), were compared with respect to the expression of neuronal (choline acetyl transferase activity: CAT) and glial (hydrocortisone-induced glutamine synthetase activity; GSase) markers of normal differentiation in cultures of 9-day chick embryo neuroretinal cells, and also with respect to the accumulation of a lens marker (δ crystallin) during so-called 'transdifferentiation' in these cultures.
MEM allows transient expression of both CAT and GSase activities in early cultures, but also permits extensive δ crystallin accumulation at later stages. F-12 medium gives somewhat higher levels of CAT and GSase activities, the former being noticeably prolonged as compared with parallel MEM cultures; δ crystallin accumulation, however, is largely inhibited in F-12 cultures. By contrast, medium 199 permits only low levels of CAT and GSase activities, perhaps because the neuronal cells are distributed individually over the glial cell sheet in 199 cultures, rather than forming aggregates as in MEM or F–12 cultures. Medium 199 also blocks δ crystallin accumulation.
The results of medium changeover between 'transdifferentiation'-permissive (MEM) and non-permissive (199, F-12) conditions suggest: (a) that potential lens precursor cells (whatever their nature) survive in F-12 medium for prolonged periods without extensive expression of the lens phenotype; (b) that such precursor cells become committed to subsequent differentiation as lens cells between 10 and 20 days of culture in permissive MEM medium (as judged by the accumulation of δ crystallin following transfer into F-12); and (c) that medium 199 can block expression of the lens phenotype even in cells already committed (by the above criteria) to lens differentiation, as for instance after 30 days of preculture in MEM. 相似文献
MEM allows transient expression of both CAT and GSase activities in early cultures, but also permits extensive δ crystallin accumulation at later stages. F-12 medium gives somewhat higher levels of CAT and GSase activities, the former being noticeably prolonged as compared with parallel MEM cultures; δ crystallin accumulation, however, is largely inhibited in F-12 cultures. By contrast, medium 199 permits only low levels of CAT and GSase activities, perhaps because the neuronal cells are distributed individually over the glial cell sheet in 199 cultures, rather than forming aggregates as in MEM or F–12 cultures. Medium 199 also blocks δ crystallin accumulation.
The results of medium changeover between 'transdifferentiation'-permissive (MEM) and non-permissive (199, F-12) conditions suggest: (a) that potential lens precursor cells (whatever their nature) survive in F-12 medium for prolonged periods without extensive expression of the lens phenotype; (b) that such precursor cells become committed to subsequent differentiation as lens cells between 10 and 20 days of culture in permissive MEM medium (as judged by the accumulation of δ crystallin following transfer into F-12); and (c) that medium 199 can block expression of the lens phenotype even in cells already committed (by the above criteria) to lens differentiation, as for instance after 30 days of preculture in MEM. 相似文献
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