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排序方式: 共有419条查询结果,搜索用时 15 毫秒
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Muhammad Mudassir Mansoor Muhammad Afzal Abu Bakar M. Raza Zeeshan Akram Adil Waqar Muhammad Babar Shahzad Afzal 《Saudi Journal of Biological Sciences》2015,22(3):317-321
Chrysoperla carnea (Stephens) is an important biological control agent currently being used in many integrated pest management (IPM) programs to control insect pests. The effect of post-treatment temperature on insecticide toxicity of a spinosyn (spinosad), pyrethroid (lambda cyhalothrin), organophosphate (chlorpyrifos) and new chemistry (acetamiprid) to C. carnea larvae was investigated under laboratory conditions. Temperature coefficients of each insecticide tested were evaluated. From 20 to 40 °C, toxicity of lambda cyhalothrin and spinosad decreased by 2.15- and 1.87-fold while toxicity of acetamiprid and chlorpyrifos increased by 2.00 and 1.79-fold, respectively. The study demonstrates that pesticide effectiveness may vary according to environmental conditions. In cropping systems where multiple insecticide products are used, attention should be given to temperature variation as a key factor in making pest management strategies safer for biological control agents. Insecticides with a negative temperature coefficient may play a constructive role to conserve C. carnea populations. 相似文献
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Muhammad A Anis I Ali Z Awadelkarim S Khan A Khalid A Shah MR Galal M Khan IA Iqbal Choudhary M 《Bioorganic & medicinal chemistry letters》2012,22(1):610-612
A new methylene-bridged bisflavonoid, methylenebissantin (1), and nine known compounds, including flavonoids (2-5), diterpenoids (6 and 7), and phenol derivatives (8-10) were isolated from the aerial parts of Dodonaea viscosa Jacq. The structure elucidation was based on spectroscopic data analyses. The isolated compounds were evaluated for the inhibition of Plasmodium falciparum enoyl-ACP reductase (PfENR). Methylenebissantin (1) exhibited a moderate inhibition (IC(50) 91.13 μM) against PfENR. 相似文献
96.
Saqib H. Ansari Tahir S. Shamsi Mushtaq Ashraf Tasneem Farzana Muneera Bohray Kousar Perveen Sajida Erum Iqra Ansari Muhammad Nadeem Ahmed Masood Ahmed Faizan Raza 《Indian journal of human genetics》2012,18(2):193-197
BACKGROUND:
β -Thalassaemia, an autosomal recessive hemoglobinopathy, is one of the commonest genetically transmitted disorders throughout the world. Collective measures including carrier identification, genetic counseling and prenatal diagnosis are required for preventing β-thalassemia.Aim:
To achieve this objective, Identification of the spectrum of genetic mutations, especially for various ethnic backgrounds in Pakistan. Therefore, we designed a cross sectional prospective study to identify the frequency of various gene mutations in different ethnic groups of Pakistan.MATERIALS AND METHODS:
Over a 5-year period, DNA from 648 blood samples {including specimens of chorionic villus sampling (CVS)} were analyzed for the twelve most common β-thalassemia mutations found in the Pakistani population by a Multiplex amplification refractory mutation system (ARMS). Each sample was analyzed for the mutation as well as the normal gene, appropriate with negative and positive controls, and reagent blanks.RESULTS:
Out of 648 samples mutations were identified in 640 (98.75%) samples by multiplex ARMS. 8 common β-thalassemia mutations were identified in 8 different ethnic groups accounting for 93.9% of the β-thalasemia alleles.CONCLUSIONS:
Based on the outcome of this study a cost effective proposal is formulated for detection of β-thalassemia mutations. 相似文献97.
Prabu SK Anandatheerthavarada HK Raza H Srinivasan S Spear JF Avadhani NG 《The Journal of biological chemistry》2006,281(4):2061-2070
We have investigated the effects of hypoxia and myocardial ischemia/reperfusion on the structure and function of cytochrome c oxidase (CcO). Hypoxia (0.1% O(2) for 10 h) and cAMP-mediated inhibition of CcO activity were accompanied by hyperphosphorylation of subunits I, IVi1, and Vb and markedly increased reactive O(2) species production by the enzyme complex in an in vitro system that uses reduced cytochrome c as an electron donor. Both subunit phosphorylation and enzyme activity were effectively reversed by 50 nm H89 or 50 nm myristoylated peptide inhibitor (MPI), specific inhibitors of protein kinase A, but not by inhibitors of protein kinase C. In rabbit hearts subjected to global and focal ischemia, CcO activity was inhibited in a time-dependent manner and was accompanied by hyperphosphorylation as in hypoxia. Additionally, CcO activity and subunit phosphorylation in the ischemic heart were nearly completely reversed by H89 or MPI added to the perfusion medium. Hyperphosphorylation of subunits I, IVi1, and Vb was accompanied by reduced subunit contents of the immunoprecipitated CcO complex. Most interestingly, both H89 and MPI added to the perfusion medium dramatically reduced the ischemia/reperfusion injury to the myocardial tissue. Our results pointed to an exciting possibility of using CcO activity modulators for controlling myocardial injury associated with ischemia and oxidative stress conditions. 相似文献
98.
Membranes are not just rafts 总被引:1,自引:0,他引:1
A new definition for lipid rafts was coined at the Keystone Symposium of Lipid Rafts and Cell Function based on recent advances in the field. The revised definition lumps all membrane heterogeneities that are not rafts into a single class of "non-raft". In this commentary, we suggest that "non-raft" domains encompass a variety of membrane heterogeneities and are quite diverse in composition and origin. A good starting point for the study of this diversity would be phospholipids with unsaturated acyl chains, which display little affinity for cholesterol; these lipids are abundant in membranes such as the endoplasmic reticulum and that may form their own macro- or microdomains. 相似文献
99.
Afsar Raza Naqvi Md. Nazrul Islam Nirupam Roy Choudhury Qazi Mohd. Rizwanul Haq. 《International journal of biological sciences》2009,5(2):97-117
Micro- and short-interfering RNAs represent small RNA family that are recognized as critical regulatory species across the eukaryotes. Recent high-throughput sequencing have revealed two more hidden players of the cellular small RNA pool. Reported in mammals and Caenorhabditis elegans respectively, these new small RNAs are named piwi-interacting RNAs (piRNAs) and 21U-RNAs. Moreover, small RNAs including miRNAs have been identified in unicellular alga Chlamydomonas reinhardtii, redefining the earlier concept of multi-cellularity restricted presence of these molecules. The discovery of these species of small RNAs has allowed us to understand better the usage of genome and the number of genes present but also have complicated the situation in terms of biochemical attributes and functional genesis of these molecules. Nonetheless, these new pools of knowledge have opened up avenues for unraveling the finer details of the small RNA mediated pathways. 相似文献
100.