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991.
Hussein H. Abulreesh Gamal E. H. Osman Abdulrahman S. A. Assaeedi 《Indian journal of microbiology》2012,52(3):500-503
This study aimed at characterizing the insecticidal genes of eight Bacillus thuringiensis isolates that were recovered from the local environment of western Saudi Arabia. The screening for the presence of lepidopteran-specific cry1A family and vip3A genes, dipteran-specific cry4 family and coleopteran-specific cry3A, vip1A and vip2A genes, was carried out by PCR. All eight isolates produced PCR products that confirmed the presence of cry1Aa, cry1Ab, cry1Ac, cry4A, cry4B genes, but not cry3A, vip1A and vip2A genes. However, three isolates only were found to carry vip3A genes as revealed by PCR. The observation of cry1 and cry4 genes suggests that these eight isolates may have dual activity against Lepidoptera and Diptera species, while three isolates possessed vip3 genes in addition to cry1 and cry4 which suggests that these three isolates have toxic crystals and vegetative proteins. The results of this study are interesting in the sense that they may help developing new strategies for controlling insects of economic and medical importance in Saudi Arabia, using B. thuringiensis strains that naturally exist in the local environment instead of the current control strategies that are based solely on chemical insecticides. 相似文献
992.
Osman Mahgoub Hamza A. Babiker I.T. Kadim Mohammed Al‐Kindi Salwa Hassan W. Al‐Marzooqi Yasmin E. Eltahir M. A. Al‐Abri Aisha Al‐Khayat Kareema R. Al‐Sinani Homoud Hilal Al‐Khanjari Vânia Costa Shanyuan Chen Albano Beja‐Pereira 《Animal genetics》2013,44(3):336-339
Among all livestock species, cattle have a prominent status as they have contributed greatly to the economy, nutrition and culture from the beginning of farming societies until the present time. The origins and diversity of local cattle breeds have been widely assessed. However, there are still some regions for which very little of their local genetic resources is known. The present work aimed to estimate the genetic diversity and the origins of Omani cattle. Located in the south‐eastern corner of the Arabian Peninsula, close to the Near East, East Africa and the Indian subcontinent, the Sultanate of Oman occupies a key position, which may enable understanding cattle dispersal around the Indian Ocean. To disclose the origin of this cattle population, we used a set of 11 polymorphic microsatellites and 113 samples representing the European, African and Indian ancestry to compare with cattle from Oman. This study found a very heterogenic population with a markedly Bos indicus ancestry and with some degree of admixture with Bos taurus of African and Near East origin. 相似文献
993.
Esengul Karahisar Osman Tugay Ilkay Erdogan Orhan Fatma Sezer Senol Deniz Simon Vlad Luca Krystyna Skalicka‐Wozniak Mustafa Sahin 《化学与生物多样性》2019,16(9)
In the current study, the ethanol extracts of flower, stem, and root parts of two endemic Turkish species, e. g., Haplophyllum sahinii O. Tugay & D. Uluku? and H. vulcanicum Boiss . & Heldr ., were screened against acetylcholinesterase (AChE) and butyrylcholinesterase (BChE) associated with Alzheimer's disease as well as tyrosinase (TYR) linked to Parkinson's disease using ELISA microplate assay at 200 μg/mL. Among the extracts, the highest inhibition was caused by the stem extract of H. sahinii against BChE (IC50=64.93±1.38 μg/mL). Consistently, all of the extracts were found to exert a selective inhibition towards BChE to some extent. It was only the root extract of H. vulcanicum that could inhibit AChE at low level (IC50=203.18±5.33 μg/mL). None of the extracts displayed an inhibition over 50 % against TYR. Metabolite profiling of the extracts was achieved by a highly hyphenated liquid chromatographic mass spectrometric technique (HPLC‐DAD‐ESI‐Q‐TOF‐MS/MS), which revealed the presence of furoquinoline (β‐fagarine, γ‐fagarine) and amide (tubasenicine, tubacetine) alkaloids; furano‐ (rutamarin), pyrano‐ (xanthyletine), and geranyloxy coumarins; phenylpropanoid (secoisolariciresinol), arylnaphthalene (mono‐O‐acetyldiphyllin apioside), and dibenzylbutyrolactone (kusunokinin, haplomyrfolin) lignans. Several important differences were observed between the extracts analyzed. β‐Fagarine was the major alkaloid in H. vulcanicum, whereas γ‐fagarine was present only in the roots of both Haplophyllum species; moreover, secoisolariciresinol and secoisolariciresinol dimethyl ether were the main lignans in the stems and flowers. This is the first study identifying ChE and TYR inhibitory effect and metabolic profiles of H. vulcanicum and H. sahinii. 相似文献
994.
Mohamed Bushra Elhassan M. Elhassan Naji I. Ali Elfatih Osman Khalid H. Bakheit Ishag I. Adam 《Biological trace element research》2010,137(3):255-261
Anaemia is a widespread problem in many parts of the world especially in tropic areas. Among pregnant women, it has negative
consequences on maternal and perinatal outcomes. A cross-sectional study was conducted to investigate the prevalence of anaemia,
iron, zinc and copper deficiencies among pregnant women in Wad Medani hospital, central Sudan and to examine the relationship
of these micronutrients with haemoglobin (Hb) levels. One hundred four (52.5%) out of 200 pregnant women had anaemia (Hb <
11 gm/dl) and 3 (1.5) % had severe anaemia (Hb < 7 gm/dl). Iron deficiency (S-ferritin < 15 μg/l), iron deficiency anaemia
(<11 gm/dl and S-ferritin < 15 μg/l) were prevalent in 25 (12.5%) and 13 (6.5%) of these women, respectively. Ninety (45.0%)
and eight (4.0%) of these women had zinc (<80 μg/ml) and copper (<80 μg/ml) deficiency, respectively. In 24 (12.0%) of these
women, there were ≥2 deficiencies of these elements. S-copper was significantly lower in patients with anaemia. While age,
parity, gestational age, ferritin, zinc and copper were not predictors for anaemia, women who practiced pica were at higher
risk for anaemia (OR = 3.4, 95% CI = 1.4–7.9, P = 0.004). Gestational age was significantly inversely correlated with haemoglobin (r = 0.161, P = 0.03), S-ferritin (r = 0.285, P = 0.001) and S-zinc (r = 0.166, P = 0.02). Thus, dietary and supplement interventions are required to prevent and control anaemia in this setting. Further research
is needed. 相似文献
995.
Amy Bogaard John Hodgson Erika Nitsch Glynis Jones Amy Styring Charlotte Diffey John Pouncett Christoph Herbig Michael Charles Füsun Ertuğ Osman Tugay Dragana Filipovic Rebecca Fraser 《Vegetation History and Archaeobotany》2016,25(1):57-73
This investigation combines two independent methods of identifying crop growing conditions and husbandry practices—functional weed ecology and crop stable carbon and nitrogen isotope analysis—in order to assess their potential for inferring the intensity of past cereal production systems using archaeobotanical assemblages. Present-day organic cereal farming in Haute Provence, France features crop varieties adapted to low-nutrient soils managed through crop rotation, with little to no manuring. Weed quadrat survey of 60 crop field transects in this region revealed that floristic variation primarily reflects geographical differences. Functional ecological weed data clearly distinguish the Provence fields from those surveyed in a previous study of intensively managed spelt wheat in Asturias, north-western Spain: as expected, weed ecological data reflect higher soil fertility and disturbance in Asturias. Similarly, crop stable nitrogen isotope values distinguish between intensive manuring in Asturias and long-term cultivation with minimal manuring in Haute Provence. The new model of cereal cultivation intensity based on weed ecology and crop isotope values in Haute Provence and Asturias was tested through application to two other present-day regimes, successfully identifying a high-intensity regime in the Sighisoara region, Romania, and low-intensity production in Kastamonu, Turkey. Application of this new model to Neolithic archaeobotanical assemblages in central Europe suggests that early farming tended to be intensive, and likely incorporated manuring, but also exhibited considerable variation, providing a finer grained understanding of cultivation intensity than previously available. 相似文献
996.
Addition of nitrate to a suspension of NO3
--depleted Chlorella vulgaris cells raised the O2-evolving capacity of the organism by 60%. The rate of O2-evolution under flash irradiation of the depleted cells was drastically reduced, which could be restored by addition of NO3
-. The 2,5-dibromo-3-methyl-6-isopropyl-p-benzoquinone (DBMIB)-insensitive O2-evolution, i.e., photosystem (PS) 2 activity of NO3--depleted cells, showed a 75% stimulation by addition of NO3
-. PS1-mediated electron transport was also stimulated (50%) by addition of NO3
-. Fluorescence yields of the NO3
--depleted cells were significantly reduced. A normal fluorescence response was restored by the addition of NO3
-. The fluorescence yield of the NO3
--depleted and DCMU-treated-cells increased significantly after addition of NO3
- ions, indicating a further reduction of the primary acceptor of PS2 (Q). In addition, the low temperature fluorescence emission
spectra showed that energy transfer to PS2 and PS1 was much higher when nitrate was present. Hence nitrate accelerates the
light-induced charge transfer from the intact O2-evolving system to the primary electron acceptor of PS2 and stimulates the PS1-mediated electron transport.
This revised version was published online in June 2006 with corrections to the Cover Date. 相似文献
997.
998.
A proton transfer triggered by a ligand interacting with the receptor had been suggested as the initial step in the activation of a receptor for the neurotransmitter serotonin (5-hydroxy-tryptamine; 5-HT). To evaluate the role of the receptor macromolecule in modulating the primary molecular event in ligand-mediated activation, the process of proton transfer was analysed in the environment of a protein model for the 5-HT receptor. In the absence of a detailed receptor structure, the enzyme actinidin was chosen as the model for the receptor based on criteria obtained from structure-activity considerations on the ligands. The first simulation of a mechanism for receptor activation was performed on this model using methods of theoretical chemistry to study the effect of specific structural elements. The premise is that the role of the elements of secondary structure of soluble proteins (e.g. actinidin) in determining structure-function relations in these macromolecules is maintained when these elements are part of membrane-bound receptor proteins. Results from the calculations of the effects of the six alpha helices of actinidin on the proton transfer process from the imidazolium side chain of His 162 to the thiol side chain of Cys 25 in the protein show that the helices contribute in different ways to modulate the energy of proton transfer. The largest helix, A1, opposes the proton transfer through the effect of the helix dipole. The charged residues (primary structure) in helix A3 favor the proton transfer, and mask the effect of its helix dipole (secondary structure) which opposes the transfer. The direction of the proton transfer simulated for the activation mechanism is opposite to that assumed in the catalytic process of the thiol protease, and the entire protein environment opposes the transfer. This supports the specific role of the ligand in triggering the proton transfer as a response to its binding. 相似文献
999.
1000.
M M Sir Eikhatim A M Osman 《Comparative biochemistry and physiology. A, Comparative physiology》1983,74(2):275-281
1. The effects of concentrate feeding on the levels and pattern of distribution of carbohydrases in bovine intestine and pancreas were investigated. 2. No remarkable difference was noticed in the pattern of distribution of the carbohydrases along the bovine intestine, which was mostly confined to the proximal part of the small intestine. 3. The concentrate feeding, however, highly affected the levels of carbohydrases in the mucosa, luminal contents and the pancreas. Their levels slightly decreased in the mucosal tissue and significantly increased in the luminal contents. In the pancreas, the level of amylase decreased and that of disaccharidases increased. 4. Based on the presence of higher levels of activities of carbohydrases in the luminal contents, supported by the concentrate-induced increase in their levels, it is argued that the site of carbohydrate digestion, including disaccharides, in the small intestine, is the luminal contents. 相似文献