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61.
Khalil Ur Rehman Shahla Andleeb Saleh Alfarraj Sulaiman Ali Alharbi Adeel Mahmood 《Saudi Journal of Biological Sciences》2021,28(5):3013-3020
This article presents the COVID-19 situation and control measures taken by the Government of Pakistan. Two waves of pandemic are faced globally and similar in the study area. We have investigated the risk management decision in two phases. Primarily, strict lockdown was observed from March 2020 to July 2020 and smart lockdown was enforced from August 2020 to December 2020. It has been studied that during strict lockdown, COVID cases reduced gradually but reopening of institutes and smart lockdown strategy resulted gradual increase in confirmed cases and death rates. During first wave of COVID-19 in Pakistan, a total confirmed number of patients of COVID-19 were 263,496 till 18th of July 2020 with total deaths of 5,568 people and 204,276 recoveries, while total number of COVID-19 patients reached 555,511 till 9th of February 2021 with total deaths of 12,026 people. Province of Sindh was affected badly with total number of 251,434 COVID-19 cases followed by Punjab Province with total number of 161,347 COVID-19 till 9th of February 2020. 相似文献
62.
Maziah Mahmood Siamak Shirani Bidabadi Cyrus Ghobadi Dennis J. Gray 《Plant Growth Regulation》2012,67(2):161-169
Although irregular monoterpenes are important and common in the Asteraceae family, little is known about their biosynthesis
at the genetic level via the MEP pathway. Chrysanthemyl diphosphate (CPP) is an intermediate in the biosynthesis of pyrethrins
which are irregular monoterpenes with excellent insecticidal activity in Tanacetum cinerariaefolium (T. cinerariaefolium). In this study, a chrysanthemyl diphosphate synthase (CDS) gene named CDS_CCI2 (GenBank accession no. HQ235057) was isolated from T. cinerariaefolium. It was homologous to T. cinerariaefolium CPP gene family, and proved to be located in the plastid by the in situ subcellular localization. CDS_CCI2 was found to be expressed in roots, stems, leaves, buds and flowers. Moreover, the expression of CDS_CCI2 can be up-regulated by abscisic acid (ABA), methyl jasmonate and ethrel treatment. Phenotypic and molecular analysis showed
that overexpression of CDS_CCI2 in micro-tom tomato resulted in dwarf phenotypes characterized with infertile flowers and seedless fruits. Furthermore, overexpression
of CDS_CCI2 altered the production of endogenous secondary metabolites. Our data indicate that CPP affects the synthesis of gibberellic
acid (GA) and ABA. 相似文献
63.
Carl Harald Janson Mahmood Jeddi Tehrani H»kan Mellstedt Hans Wigzell 《Cancer immunology, immunotherapy : CII》1989,28(3):225-232
Summary A murine anti-idiotypic monoclonal antibody (mAb), F1, (IgG2a) was produced against the variable part of the T-cell receptor for antigen (Ti, /) on the tumor cells of a patient with T-cell chronic lymphatic leukemia (CD3+, 8+, 4–). The molecular weight of the protein reactive with mAb F1, comodulation and coprecipitation with anti-CD3 antibody, and the restricted tumor-cell reactivity strongly support the anti-idiotypic nature of mAb F1. MAb F1 also stained 4% of peripheral blood lymphocytes of healthy donors. MAb F1 did not stimulate the tumor cells to DNA synthesis, but stimulated a fraction of the normal peripheral blood lymphocytes, mAb F1 did not mediate antibody-dependent cellular cytotoxicity or complement lysis to any significant degree in vitro. Three infusions of 1–10 mg anti-idiotypic mAb were given over a period of 4 weeks. The plasma half-life for mAb F1 was 3 h in the first 2 h after infusion and 44 h from 2 h to 120 h after infusion. After each treatment a rapid decrease of circulating tumor cells was seen. During the observation period an 80% reduction of the total circulating tumor cells was noted. After the second infusion, IgM and IgG antimouse antibodies were detected. Side-effects from therapy were fever, chills, nausea, vomiting, diarrhea, tachycardia, increase in systolic blood pressure and shortness of breath. Thus, in T-cell malignancies a major reduction of circulating tumor cells can be accomplished by low doses of anti-idiotypic mAb. Anti-idiotypic mAb might be a therapeutic agent of significant importance. 相似文献
64.
Application of phosphorus at 40, 60, 80 and 100 kg P2O5 ha–1 in the presence of a uniform dressing of nitrogen (N) and potash (K2O) each applied at 20 and 24 kg ha–1 to chickpea (CM-88) grown in sandy loam soil in a replicated field experiment improved the nodulation response of the crop, increased its grain yield (ka ha–1) by 18, 59, 40 and 14 percent, biomass yield (ka ha–1) by 32, 32, 54 and 14 percent, biomass N (kg ha–1) by 31, 48, 49, 19 percent, and biomass P (kg ha–1) by 26, 40, 41 and 11 percent, respectively. The effect of phosphorus on the nitrogenase activity of the excised roots of chickpea was, however, inconsistent. 相似文献
65.
Seyed Jafar Mousavy Gholam Hossein Riazi Mahmood Kamarei Hadi Aliakbarian Naghmeh Sattarahmady Ahmad Sharifizadeh Shahrokh Safarian Faizan Ahmad Ali Akbar Moosavi–Movahedi 《International journal of biological macromolecules》2009,44(3):278-285
Widespread use of mobile phones has increased the human exposure to electromagnetic fields (EMFs). It is required to investigate the effect of EMFs on the biological systems. In this paper the effect of mobile phone RF (910 MHz and 940 MHz) on structure and function of HbA was investigated. Oxygen affinity was measured by sodium dithionite with UV–vis spectrophotometer. Structural changes were studied by circular dichroism and fluorescence spectroscopy. The results indicated that mobile phone EMFs altered oxygen affinity and tertiary structure of HbA. Furthermore, the decrease of oxygen affinity of HbA corresponded to the EMFs intensity and time of exposure. 相似文献
66.
Creatine (Cr) is naturally produced in the body and stored in muscles where it is involved in energy generation. It is widely used, especially by athletes, as a staple supplement for improving physical performance. Recent reports have shown that Cr displays antioxidant activity which could explain its beneficial cellular effects. We have evaluated the ability of Cr to protect human erythrocytes and lymphocytes against oxidative damage. Erythrocytes were challenged with model oxidants, 2, 2''-azobis(2-amidinopropane) dihydrochloride (AAPH) and hydrogen peroxide (H2O2) in the presence and absence of Cr. Incubation of erythrocytes with oxidant alone increased hemolysis, methemoglobin levels, lipid peroxidation and protein carbonyl content. This was accompanied by decrease in glutathione levels. Antioxidant enzymes and antioxidant power of the cell were compromised while the activity of membrane bound enzyme was lowered. This suggests induction of oxidative stress in erythrocytes by AAPH and H2O2. However, Cr protected the erythrocytes by ameliorating the AAPH and H2O2 induced changes in these parameters. This protective effect was confirmed by electron microscopic analysis which showed that oxidant-induced cell damage was attenuated by Cr. No cellular alterations were induced by Cr alone even at 20 mM, the highest concentration used. Creatinine, a by-product of Cr metabolism, was also shown to exert protective effects, although it was slightly less effective than Cr. Human lymphocytes were similarly treated with H2O2 in absence and presence of different concentrations of Cr. Lymphocytes incubated with oxidant alone had alterations in various biochemical and antioxidant parameters including decrease in cell viability and induction of DNA damage. The presence of Cr attenuated all these H2O2-induced changes in lymphocytes. Thus, Cr can function as a blood antioxidant, protecting cells from oxidative damage, genotoxicity and can potentially increase their lifespan. 相似文献
67.
Adedipe Tosin Shafiee Mahmood 《The International Journal of Life Cycle Assessment》2021,26(2):344-370
The International Journal of Life Cycle Assessment - As wind power generation increases globally, there will be a substantial number of wind turbines that need to be decommissioned in the coming... 相似文献
68.
In this protocol, we describe a procedure for incorporating ATP-binding cassette (ABC) transporters into large unilamellar vesicles (LUVs) and assays to determine ligand binding and solute translocation by these membrane-reconstituted systems. The reconstitution technique as described has been optimized for ABC transporters but can be readily adapted for other types of transport systems. Purified transporters are inserted into detergent-destabilized preformed liposomes and detergent is subsequently removed by adsorption onto polystyrene beads. Next, Mg-ATP or an ATP-regenerating system is incorporated into the vesicle lumen by one or more cycles of freezing-thawing, followed by extrusion through polycarbonate filters to obtain unilamellar vesicles. Binding and translocation of substrates are measured using isotope-labeled ligands and rapid filtration to separate the proteoliposomes from the surrounding medium. Quantitative information is obtained about dissociation constants (K(d)) for ligand binding, number of binding-sites, transport affinities (K(m)), rates of transport, and the activities of transporter molecules with opposite orientations in the membrane. The full protocol can be completed within 4-5 d. 相似文献
69.
3D Vertically Aligned and Interconnected Porous Carbon Nanosheets as Sulfur Immobilizers for High Performance Lithium‐Sulfur Batteries 下载免费PDF全文
Sarish Rehman Xingxing Gu Kishwar Khan Nasir Mahmood Wenlong Yang Xiaoxiao Huang Shaojun Guo Yanglong Hou 《Liver Transplantation》2016,6(12)
A unique nanostructure of 3D and vertically aligned and interconnected porous carbon nanosheets (3D‐VCNs) is demonstrated by a simple carbonization of agar. The key feature of 3D‐VCNs is that they possess numerous 3D channels with macrovoids and mesopores, leading to high surface area of 1750 m2 g?1, which play an important role in loading large amount of sulfur, while vertically aligned microporous carbon nanosheets act as the multilayered physical barrier against polysulfides anions and prevent their dissolution in the electrolyte due to strong adsorption during cycling process. As a result, the 3D hybrid (3D‐S‐VCNs) infiltered with 68.3 wt% sulfur exhibits a high and stable reversible capacity of 844 mAh g?1 at the current density of 837 mA g?1 with excellent Coulombic efficiency ≈100%, capacity retention of ≈80.3% over 300 cycles, and good rate ability (the reversible capacity of 738 mAh g?1 at the high current density of 3340 mA g?1). The present work highlights the vital role of the introduction of 3D carbon nanosheets with macrovoids and mesopores in enhancing the performance of LSBs. 相似文献
70.
Heyam Mohamed Ali Sidahmed Najihah Mohd Hashim Mahmood Ameen Abdulla Hapipah Mohd Ali Syam Mohan Siddig Ibrahim Abdelwahab Manal Mohamed Elhassan Taha Loke Mun Fai Jamuna Vadivelu 《PloS one》2015,10(3)