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排序方式: 共有468条查询结果,搜索用时 15 毫秒
1.
K E el Tahir E A Hamad A M Ageel M A Abu Nasif E A Gadkarim 《Prostaglandins, leukotrienes, and essential fatty acids》1990,40(1):63-66
Influences of 2.5 and 5% (w/v) aqueous tea and coffee beverages administered ad lib. to rats for two weeks on PGI2 synthesis by the rat thoracic aorta in vitro were investigated using a rat platelet antiaggregatory bioassay and HPLC methods. The 2.5% beverages did not affect PGI2 synthesis; however, the 5% beverages significantly decreased PGI2 synthesis. The observed decreases were significantly abolished in presence of exogenous arachidonic acid suggesting a beverage-induced inhibition of precursor release. The ability of the beverages to inhibit PGI2 synthesis may partly contribute towards better understanding of the biochemical mechanisms underlying some of the beverages-induced actions in vivo. 相似文献
2.
Bacteria of public health significance in blackcurrant juice 总被引:1,自引:0,他引:1
A total of 192 samples of blackcurrant juice were investigated for hygienic quality and drug resistance. The average aerobic bacteria in 1 ml of the blackcurrant juice was 4.8 x 10(8) and the average MPN was 8.4 x 10(2) coliform/100 ml. The percentage of the samples contaminated with coliform bacteria was 23.4. The incidence of Escherichia coli, Klebsiella, Pseudomonas aeruginosa, Staphylococcus aureus and faecal streptococci were 19.8, 9.9, 29.2, 14.0 and 18.2%, respectively. Biochemical and serological studies showed that 10.5% of total Escherichia coli were enteropathogenic E. coli. Of sixty strains tested against six antibacterial drugs, 57% were resistant to one or more of the drugs. The incidence of resistance to ampicillin, chloramphenicol, sulphonamide, streptomycin, tetracyline and gentamycin was 40.0, 25.0, 43.3, 18.3, 20.0 and 8.3%, respectively. 相似文献
3.
The influence of taurine (in drinking water for 6 weeks) on PGI2 and TXA2 synthesis by some female rat organs was investigated using radioimmunoassay and platelet antiaggregatory bioassay. Taurine 100 and 200 mg/kg/day increased aortic PGI2 release from 0.59 ± 0.04 (control) to 0.85 ± 0.05 and 1.01 ± 0.06 ng/mg, respectively and that by the myometrium from 0.24 ± 0.02 (control) to 0.38 ± 0.01 and 0.50 ± 0.04 ng/mg wet tissue, respectively (P < 0.05, n = 6). It did not affect PGI2 and TXA2 production in the heart or TXA2 in the aorta. Taurine 200 mg/kg depressed uterine TXA2 synthesis from 148.6 ± 9.8 (control) to 85.4 ± 6.8 pg/mg (P < 0.05, n = 6). Furthermore taurine 0.4 and 0.8 mM in vitro stimulated PGI2 released by the myometrial and aortic tissues from pregnant rats. The stimulant effect of taurine on PGI2 may be related to its antioxidant effect whereas its inhibitory effect on uterine TXA2 may result from direction of synthesis towards PGI2. It is concluded that endogenous taurine may participate in regulation of PGs synthesis and that prostanoids may contribute to its known actions. On broad basis, taurine-induced release of PGI2 may prove of potential value in those ailments characterised by deficiency in PGI2 release. 相似文献
4.
M. Tahir A. Pavoni G. F. Tucci T. Turchetta D. Lafiandra 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》1996,92(6):654-659
A hexaploid wheat landrace collected from the Baluchistan province of Pakistan was found to possess a novel high-molecular-weight glutenin subunit (HMW-GS). The subunit has a very slow electrophoretic mobility as revealed by SDS-PAGE, and its molecular weight is comparable to that of the highest molecular weight glutenin subunit (2.2 encoded in the D-genome) reported so far in hexaploid wheat varieties and landraces of Japanese origin. Evidence obtained from (PCR) gene amplification studies using the primers specific for Glu-1 loci proved that the gene coding for this novel subunit belongs to the Glu-A1 locus located on the long arm of chromosome 1A. Digestion of the amplified gene (PCR product) with restriction enzymes indicated that the novel gene differs from prevailing Glu-A1 alleles (null, 1 and 2*) by an extra DNA fragment of approximately 600 base pairs. The results also indicated that the novel subunit is most probably a derivative of subunit 2* that has very likely incorporated the 600-bp fragment following a process of unequal crossing over. The present findings were further substantiated by reserved phase high performance liquid chromatography (RP-HPLC) analysis. 相似文献
5.
Indigenous Arbuscular Mycorrhizal Fungi Associated with Acacia albida Del. in Different Areas of Senegal 下载免费PDF全文
Tahir A. Diop Mamadou Gueye Bernard L. Dreyfus Christian Plenchette Desire G. Strullu 《Applied microbiology》1994,60(9):3433-3436
The influences of seasons, plant age, and physicochemical properties of the soil on surface and deep biological arbuscular mycorrhizal fungus parameters associated with Acacia albida were assessed in different areas of Senegal. More indigenous arbuscular mycorrhizal propagules were found in the localities of the Sudano-Guinean zone (Djinaki and Kabrousse) than in those of the Sahelian zone (Louga and Diokoul), and species belonging to the genera Glomus, Gigaspora, Acaulospora, and Sclerocystis prevailed. The numbers of total and viable spores increased more during the rainy season than during the dry season (about 108% more total spores and 262% more viable spores). Similarly, both total and viable spores were more prevalent around young Acacia trees than old trees. However, the intensities of root colonization did not differ in each ecoclimatic zone. 相似文献
6.
W. Erskine A. Hussain M. Tahir A. Bahksh R. H. Ellis R. J. Summerfield E. H. Roberts 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》1994,88(3-4):423-428
A model to predict flowering time in diverse lentil genotypes grown under widely different photothermal conditions was developed in controlled environments. The present study evaluated that model with a world germ plasm collection of 369 accessions using two field environments in Syria and two in Pakistan. Photoperiod alone accounted for 69% of the variance in 1/f, the reciprocal of time (d) from sowing to flower. In contrast, temperature alone did not account for a significant proportion of variation in flowering time due to the exposure of plants to supra-optimal temperatures in the late-sown Syrian trial. With the model mean pre-flowering values of photoperiod and temperature combined additively to account for 90.3% of the variance of 1/f over accessions. The correlation of field-derived estimates of temperature sensitivity of accessions to glass-house-derived estimates was significant at P = 0.05, but the equivalent correlation for estimates of photoperiodic sensitivity was higher at P < 0.01. Flowering in the field was better measured as time from sowing to 50% plants in flower rather than time to first bloom or its node number. Dissemination of the lentil crop following domestication in West Asia to the lower latitudes such as Ethiopia and India has depended on selection for intrinsic earliness and reduced sensitivity to photoperiod. Movement from West Asia to the higher latitudes accompanied by spring sowing has resulted in a modest reduction in photoperiod sensitivity and an increase in temperature sensitivity. 相似文献
7.
Mohd Imran Shahzad Ahmed Ahmad Zuhairi Abdullah Jabir Hakami Anis Ahmad Chaudhary Hassan Ahmad Rudayni Salah-Ud-Din Khan Afzal Khan Nosiba Suliman Basher 《Luminescence》2023,38(7):1064-1086
The penicillin derivative amoxicillin (AMX) plays an important role in treating various types of infections caused by bacteria. However, excessive use of AMX may have negative health effects. Therefore, it is of utmost importance to detect and quantify the AMX in pharmaceutical drugs, biological fluids, and environmental samples with high sensitivity. Therefore, this review article provides valuable and up-to-date information on nanostructured material-based optical and electrochemical sensors to detect AMX in various biological and chemical samples. The role of using different nanostructured materials on the performance of important optical sensors such as colorimetric sensors, fluorescence sensors, surface-enhanced Raman scattering sensors, chemiluminescence/electroluminescence sensors, optical immunosensors, optical fibre-based sensors, and several important electrochemical sensors based on different electrode types have been discussed. Moreover, nanocomposites, polymer, and MXenes-based electrochemical sensors have also been discussed, in which such materials are being used to further enhance the sensitivity of these sensors. Furthermore, nanocomposite-based photo-electrochemical sensors and the market availability of biosensors including AMX have also been discussed briefly. Finally, the conclusion, challenges, and future perspectives of the above-mentioned sensing techniques for AMX detection are presented. 相似文献
8.
9.
Khan Salman Khan Mukhtaj Iqbal Nadeem Hussain Tahir Khan Sher Afzal Chou Kuo-Chen 《International journal of peptide research and therapeutics》2020,26(2):795-809
International Journal of Peptide Research and Therapeutics - Piwi interacting RNA (piRNA) molecules belong to a largest class of small non coding RNA molecules which are originally discovered in... 相似文献
10.
Khan Muhammad Tahir Zeb Muhammad Tariq Ahsan Hina Ahmed Abrar Ali Arif Akhtar Khalid Malik Shaukat Iqbal Cui Zhilei Ali Sajid Khan Anwar Sheed Ahmad Manzoor Wei Dong-Qing Irfan Muhammad 《Archives of microbiology》2021,203(1):59-66
Archives of Microbiology - Severe acute respiratory syndrome virus 2 (SARS-CoV-2) belongs to the single-stranded positive-sense RNA family. The virus contains a large genome that encodes four... 相似文献