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511.
Effects of sublethal doses ie, 2, 4, 10, and 20 ppm of cypermethrin, were studied on the sixth-instar larvae of Tribolium castaneum (Herbst.). Of all the biochemical parameters tested, the free amino acids and cholesterol content and the activity of amylase were found to be the most sensitive components. Glutamate pyruvate transaminase activity was elevated at all doses except 2 ppm. The activities of alkaline phosphatase and glutamate oxaloacetate transaminase and glucose content were raised significantly at doses of 10 and 20 ppm. Acid phosphatase activity and the soluble protein content increased at a dose of 20 ppm. Total lipid and triglycerides, however, decreased significantly at this sublethal dose. Other biochemical parameters, such as cholinesterase and lactate dehydrogenase activities and the total protein, urea, glycogen, DNA, and RNA contents, were not significantly affected by exposure to different doses of cypermethrin. 相似文献
512.
Alcohol dehydrogenase activity in the human tissues 总被引:1,自引:0,他引:1
Total and specific alcohol dehydrogenase activity has been compared in homogenates of 19 different types of human tissues from different sources. ADH activities were detected in tissues which have not been tested yet, e.g., thyroid gland, adrenal gland, fat tissue, skin tissue, peritoneal membrane, breast tissue, duodenum, and gall bladder. Healthy and pathological human tissue differ in their ADH activity. The percentage of the total activity has been estimated in each tested organ in relation to the total activity of the whole body. 相似文献
513.
Muhammad Nasir Amin Salman Zaheer Abdulrahman Ali Alazba Muhammad Umair Saleem Muhammad Umar Khan Niazi Nauman Khurram Muhammad Tahir Amin 《PloS one》2016,11(2)
Structural hollow sections are gaining worldwide importance due to their structural and architectural advantages over open steel sections. The only obstacle to their use is their connection with other structural members. To overcome the obstacle of tightening the bolt from one side has given birth to the concept of blind bolts. Blind bolts, being the practical solution to the connection hindrance for the use of hollow and concrete filled hollow sections play a vital role. Flowdrill, the Huck High Strength Blind Bolt and the Lindapter Hollobolt are the well-known commercially available blind bolts. Although the development of blind bolts has largely resolved this issue, the use of structural hollow sections remains limited to shear resistance. Therefore, a new modified version of the blind bolt, known as the “Extended Hollo-Bolt” (EHB) due to its enhanced capacity for bonding with concrete, can overcome the issue of low moment resistance capacity associated with blind-bolted connections. The load transfer mechanism of this recently developed blind bolt remains unclear, however. This study uses a parametric approach to characterising the EHB, using diameter as the variable parameter. Stiffness and load-carrying capacity were evaluated at two different bolt sizes. To investigate the load transfer mechanism, a component-based study of the bond and anchorage characteristics was performed by breaking down the EHB into its components. The results of the study provide insight into the load transfer mechanism of the blind bolt in question. The proposed component-based model was validated by a spring model, through which the stiffness of the EHB was compared to that of its components combined. The combined stiffness of the components was found to be roughly equivalent to that of the EHB as a whole, validating the use of this component-based approach. 相似文献
514.
Zeeshan Iqbal Daniel C. Hoessli Afshan Kaleem Jawaria Munir Muhammad Saleem Imran Afzal Abdul Rauf Shakoori Nasir‐ud‐Din 《Journal of cellular biochemistry》2013,114(4):874-887
Proteins function is regulated by co‐translational modifications and post‐translational modifications (PTMs) such as phosphorylation, glycosylation, and acetylation, which induce proteins to perform multiple tasks in a specified environment. Acetylation takes place post‐translationally on the ε‐amino group of Lys in histone proteins, allowing regulation of gene expression. Furthermore, amino group acetylation also occurs co‐translationally on Ser, Thr, Gly, Met, and Ala, possibly contributing to the stability of proteins. In this work, the influence of amino acids next to acetylated sites has been investigated by using MAPRes (Mining Association Patterns among preferred amino acid residues in the vicinity of amino acids targeted for PTMs). MAPRes was utilized to examine the sequence patterns vicinal to modified and non‐modified residues, taking into account their charge and polarity. The PTMs data were further sub‐divided according to their sub‐cellular location (nuclear, mitochondrial, and cytoplasmic), and their association patterns were mined. The association patterns mined by MAPRes for acetylated and non‐acetylated residues are consistent with the existing literature but also revealed novel patterns. These rules have been utilized to describe the acetylation and its effects on the protein structure‐function relationship. J. Cell. Biochem. 114: 874–887, 2013. © 2012 Wiley Periodicals, Inc. 相似文献
515.
Alatawi Aishah Wang Xiukang Saleem Muhammad Hamzah Mohsin Muhammad Rehman Muzammal Usman Kamal Fahad Shah Mfarrej Manar Fawzi Bani Hefft Daniel Ingo Ali Shafaqat 《Journal of Plant Growth Regulation》2023,42(2):1186-1211
Journal of Plant Growth Regulation - Copper (Cu) pollution in agricultural soils is considered as a serious health risk due to its accumulation in plants. Thus, there is an urgent need to optimize... 相似文献
516.
Hussain Hidayat Nazir Mamona Saleem Muhammad Al-Harrasi Ahmed Elizbit Green Ivan R. 《Phytochemistry Reviews》2021,20(1):145-179
Phytochemistry Reviews - In recent years the prevalence of diabetes has increased globally and by 2040 the number of diabetic people has been estimated to increase to 642 million. Various classes... 相似文献
517.
Design and cloning of a synthetic gene for the flounder antifreeze protein and its expression in plant cells 总被引:11,自引:0,他引:11
A synthetic gene coding for the winter flounder antifreeze protein (AFP) has been constructed. A new strategy for the synthesis has been employed such that one strand of the duplex was chemically synthesized and the other was produced enzymatically by chain extension. The chemically synthesized blocks were constructed so that the second strand was self-priming. The resulting DNA fragment was incorporated into the vector, pGCS1, which contained a translational fusion of the sequence encoding AFP and the N terminus of cat (encoding chloramphenicol acetyltransferase, CAT), under the control of the cauliflower mosaic virus 35S promoter. This plasmid was introduced into protoplasts of corn (var. Black Mexican Sweet) by electroporation. Production of the fusion peptide was monitored by CAT assay and Western blotting with antisera to AFP and CAT. 相似文献
518.
519.
Maryam Akram Maria Saleem Khan Sammia Shahid Hafiz Muhammad Abdur Rahman Iram Nadeem 《Bioscience, biotechnology, and biochemistry》2020,84(10):1967-1974
ABSTRACT This work presents the development and validation of a simple, rapid, and cost-effective spectrophotometric method for quantitative analysis of uric acid in biological samples. The method relies upon uric acid-led reduction of Fe(III) to Fe(II) of sample/standard solutions which stoichiometrically engages ferrozine to form a magenta-colored complex. Different parameters including pH, metal and chelator concentrations, temperature, etc., were optimized for the maximum intensity and stability of the complex. The uric acid concentrations of synthetic/plasma solutions were determined by comparing the color intensity of Fe(ferrozine)3 2+ complex produced by test solution with the standard curve formed by known uric acid concentrations. The method was validated in accordance with ICH guidelines and subjected to human plasma analysis. The results obtained were compared with a reference (enzymatic) method which revealed that there was no significant difference between the two methods at 95% confidence level. The method is highly specific, precise, linear, accurate, and robust. 相似文献
520.
Esmail Jafari Abdus Saleem Bahu S. Shaikh Laurence M. Demers 《Prostaglandins & other lipid mediators》1976,12(5):829-835
When platelet rich plasma is exposed to N-ethylmaleimide, a ten fold increase in measurable prostaglandin E synthesis occurs. This effect is almost completely abolished within 2 hours of ingestion of 600 mg of aspirin by human volunteers. Recovery of this platelet function is slow for the first two days, returning sharply to normal over the next six days and plateauing approximately 8 days following initial removal from aspirin. It is suggested from these studies that platelet prostaglandin E production following NEM may be a useful test of platelet function. 相似文献