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11.
Bacteriophage MB78, a virulent phage ofSalmonella typhimurium cannot grow in rifampicin-resistant mutant (rif-39) of the host having altered RNA polymerase. The temperate phage P22 which
cannot multiply in presence of the virulent phage MB78 can, however, help MB78 to overcome replication inhibition in rif-39.
The processing of concatemeric phage DNA to monomer is blocked in this nonpermissive host. Superinfection with P22 induces
synthesis of at least five P22 specific polypeptides which help phage MB78 in the processing of the concatemeric DNA and maturation
of phage particles. 相似文献
12.
Matthew R. Wright Saeed Sattari Dion R. Brocks Fakhreddin Jamali 《Journal of chromatography. B, Analytical technologies in the biomedical and life sciences》1992,583(2)
A rapid, inexpensive and sensitive high-performance liquid chromatographic method for the quantitation of ibuprofen enantiomers from a variety of biological fluids is reported. This method uses a commercially available internal standard and has significantly less interference from endogenous co-extracted solutes than do previously reported methods. The method involves the acid extraction of drug and internal standard [(±)-fenoprofen] from the biological fluid with isooctane—isopropanol (95:5) followed by evaporation and derivatization with enthylchloroformate and R-(+)-α-phenylethylamine. Excellent linearity was observed between the peak-area ratio and enantiomer concentration (r > 0.99) over a concentration range of 0.25–50 μg/ml. This method is suitable for the quantitation of ibuprofen from single-dose pharmacokinetic studies involving either rats or humans. 相似文献
13.
Prostaglandin Profiles in Tissue and Blood Vessels from Human Brain 总被引:12,自引:8,他引:4
M. Saeed Abdel-Halim H. von Holst B. Meyerson C. Sachs E. Änggård 《Journal of neurochemistry》1980,34(5):1331-1333
14.
H.O.J. Collier Alison A. Francis Wendy J. McDonald-Gibson S.A. Saeed 《Prostaglandins & other lipid mediators》1976,11(2):219-225
Sulphasalazine (SZ) inhibits prostaglandin (PG) biosynthesis with a potency comparable to that of aceylsalicylate. The metabolites of SZ, sulphapyridine and 5-aminosalicylic acid, were of considerably lower potency as inhibitors of PG biosynthesis in the synthetase preparations used. The inhibition of prostaglandin production by SZ could at least partly account for the clinical utility of sulphasalazine in ulcerative colitis. Sulphapyridine may help to maintain inhibitory concentrations of SZ by restraining bacterial breakdown of the active drug. 相似文献
15.
Further evidence is given that dependence arises from the agonist action of opiates. From this and our previous propositions assigning a fundamental role to neuronal cyclic AMP in (i) the agonist action of opiates and (ii) the expression of the abstinence syndrome, it follows that opiate dependence is a state of heightened potential activity of a neuronal cyclic AMP mechanism, initiated and maintained by the blockade of an adenylate cyclase. Various possible mechanisms are discussed by which this potential is heightened. New evidence is given that morphine and naloxone stimulate prostaglandin biosynthesis without mutual antagonism. Preliminary evidence also is given that (i) the formation of cyclic AMP is enhanced in brain homogenates from heroin-dependent rats, and (ii) an acidified ethylacetate extract of brains of morphine-dependent rats induces quasi-abstinence effects when injected into a lateral cerebral ventricle of naive rats. 相似文献
16.
17.
Saeed Bahrami Moqadam Ahamd Saleh Asheghabadi Farzaneh Norouzi Hamed Jafarzadeh Ali Khosroabadi Afshin Alagheband Ghazal Bangash Negar Morovatdar Jing Xu 《仿生工程学报(英文版)》2021,18(6):1344-1357
Lack of temperature sensation of myoelectric prosthetic hand limits the daily activities of amputees.To this end,a non-invasive temperature sensation method is proposed to train amputees to sense temperature with psychophysical sensory substitution.In this study,22 healthy participants took part besides 5 amputee participants.The duration time of the study was 31 days with five test steps according to the Leitner technique.An adjustable temperature mug and a Peltier were used to change the temperature of the water/phantom digits to induce temperature to participants.Also,to isolate the surround-ings and show colors,a Virtual Reality(VR)glass was employed.The statistical results conducted are based on the response of participants with questionnaire method.Using Chi-square tests,it is concluded that participants answer the experiment significantly correctly using the Leitner technique(P value<0.05).Also,by applying the"Repeated Measures ANOVA",it is noticed that the time of numbness felt by participants had significant(P value<0.001)difference.Participants could remember lowest and highest temperatures significantly better than other temperatures(P value<0.001);furthermore,the well-trained amputee participant practically using the prosthesis with 72.58%could identify object's temperature with only once time experimenting the color temperature. 相似文献
18.
Predicting gene expression from sequence 总被引:36,自引:0,他引:36
19.
Asha Thomas Georgia D. Tourassi Adel S. Elmaghraby Roland Valdes Jr. Saeed A. Jortani 《Clinical proteomics》2006,2(1-2):13-32
Data mining application to proteomic data from mass spectrometry has gained much interest in recent years. Advances made in proteomics and mass spectrometry have resulted in considerable amount of data that cannot be easily visualized or interpreted. Mass spectral proteomic datasets are typically high dimensional but with small sample size. Consequently, advanced artificial intelligence and machine learning algorithms are increasingly being used for knowledge discovery from such datasets. Their overall goal is to extract useful information that leads to the identification of protein biomarker candidates. Such biomarkers could potentially have diagnostic value as tools for early detection, diagnosis, and prognosis of many diseases. The purpose of this review is to focus on the current trends in mining mass spectral proteomic data. Special emphasis is placed on the critical steps involved in the analysis of surface-enhanced laser desorption/ionization mass spectrometry proteomic data. Examples are drawn from previously published studies and relevant data mining terminology and techniques are exlained. 相似文献
20.
Waqar Jaleel Shafqat Saeed Qamar Saeed Muhammad Nadir Naqqash Muhammad Umair Sial Qurat Ul Aine Lei Yanyuan Zhao Rui Yurong He Lihua Lu 《Entomological Research》2019,49(4):151-157
Plutella xylostella is an important pest of cruciferous crops worldwide. However, information regarding the age‐stage, two‐sex life parameters of P. xylostella, which is vital for designing more effective control methods, is currently lacking. The present study reports age‐stage, two‐sex life table parameters for P. xylostella on napa cabbage (Brassica oleracea var. napa), white cabbage (B. oleracea var. capitata), and cauliflower (B. oleracea var. botrytis) under laboratory conditions at 25 ± 2°C, 50–60% relative humidity, and a 16‐h light : 8‐h dark photoperiod. The time for development from an egg to a male or female adult P. xylostella on white cabbage (mean [± SE] 41.15 ± 0.54 and 39.50 ± 0.54 days, respectively) was significantly longer than that on cauliflower and napa cabbage. Furthermore, P. xylostella fecundity on cauliflower (261.90 ± 4.53 eggs female) was significantly highest than on napa cabbage and white cabbage. Intrinsic rate of increase (r) and finite rate of increase (λ) were highest on cauliflower 0.182 day?1 and 1.199 day?1 respectively as comparison to napa cabbage and white cabbage. The highest gross reproductive rate (GRR) and net reproductive rates (R0) of P. xylostella 65.87 and 52.58 respectively on cauliflower then those of other hosts. The findings of the present study indicate that cauliflower is the most suitable cultivar (host) for the development of P. xylostella. Based on these findings, crops like cauliflower can be used as trap crops when napa cabbage and white cabbage are the main crops. 相似文献