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61.
Anvarhusein A. Isab Ibrahim H. Ghazi Mohammed I. M. Wazeer Herman P. Perzanowski 《Journal of inorganic biochemistry》1993,50(4):299-304
15N NMR studies of the interaction of 15N cyanide ion with gold(I)-thiomalate (Autm) and gold(I)-thioglucose (Autg) have been carried out at pH* 7.40. The chemical shifts of the two 15N ions containing species Au(C15N)2− and RS-Au-C15N− (where RS− = tm− or tg−) were identified at 265.94 and 260.30 ppm, respectively. From the broadened 15N NMR signals, approximate life times of the RS-Au-CN− species were calculated. 相似文献
62.
Mohsen A. F. El-Hazmi Hassan M. Bahakim Arjumand S. Warsy Abdulkarim Al-Momen Abdullah Al-Wazzan Ibrahim Al-Fawwaz Sameer Huraib Mohammad Harakati 《Molecular and cellular biochemistry》1993,124(1):17-22
Sickle cell anaemia (SCA) exhibits significant variations in clinical presentation in different populations for which several genetic factors including SCA-associated -and -thalassaemias, G-6-PD deficiency and elevated Hb F level have been implicated as possible ameliorating factors. Saudi Arabia is unique in that mild and severe forms of the disease occur at a high frequency. We investigated the G/A ratio and Hb F level and correlated these values with the severity of SCA. The results showed that Hb F level varies significantly in both groups of patients with no evident correlation with the mild clinical manifestations. However, G/A ratio correlated significantly with the disease severity where a high ratio was observed in patients with the mild and a low ratio in patients with the severe disease. The results are evaluated and discussed in the light of correlation studies and regression analysis. 相似文献
63.
Mahmoud A. Ibrahim Abdel-Hady M. Ghazy Tahany M. Maharem Mohamed I. Khalil 《Comparative biochemistry and physiology. Part B, Biochemistry & molecular biology》2001,130(4)
An inhibitor of factor Xa (FXa) was isolated from the nymphs of the camel tick Hyalomma dromedarii by a combination of chromatography on DEAE-cellulose and Sephacryl S-300 columns. The isolated nymphal FXa inhibitor turned out to be a homogenous preparation of a single polypeptide chain (15 kDa) as judged by both the native and denatured SDS-PAGE. Its pI value ranged from 7.7 to 7.9. The inhibitor is a potent anticoagulant since it prolonged both the activated partial thromboplastin time (APTT) and the prothrombin time (PT) of the camel plasma in a concentration-dependent manner. Its activity was threefold lower toward thrombin than FXa, but it did not inhibit any of the proteases; trypsin, α-chymotrypsin, papain, pepsin and subtilisin. The inhibitor binds at two sites on FXa uncompetitively with an inhibition constant (Ki) value of 134 nM. 相似文献
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Suspension cultures of Perilla ocymoides accumulate caffeic acid, both in free and ester forms, as the only phenylpropanoid end metabolite. Increased levels of growth substances influenced the levels of PAL activity and phenolic accumulation so that cytokinin stimulated, while auxin repressed both parameters. The regulatory role of caffeyl compounds is discussed in relation to their accumulation during the early exponential phase of culture growth. 相似文献
67.
A M Ibrahim Y M Shaker M F el-Hawary K I Fayek M M Zahran N K el-Shawarby 《Clinical physiology and biochemistry》1985,3(1):16-22
Total serum protein levels in 70 patients with urolithiasis were not significantly different from those in 20 control subjects, although certain variations were detected in individual protein patterns. In contrast, total urinary protein was significantly higher in patients with urolithiasis. 4-6 different components, i.e., albumin, alpha 1-acidic glycoprotein, alpha 1-antitrypsin, Gc-globulin, fibrinogen and immunoglobulin G, were found in the matrices of calculi and in urine, suggesting that proteinuria may play a role in the formation of stones in patients with urolithiasis. 相似文献
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Hamed A. El-Serehy Khaled A. Al-Rasheid Nesreen K. Ibrahim Fahad A. Al-Misned 《Saudi Journal of Biological Sciences》2015,22(6):789-794
A reproductive biology study of the spider crab Schizophrys aspera (H. Milne Edwards, 1834) was conducted in the Suez Canal from July 2012 to June 2013. The annual sex ratio (Male:Female) of S. aspera was female biased with values of 1:1.25. Out of the four ovarian development stages of this crab, two stages were observed in the Suez Canal throughout the whole year. The ovigerous crab’s carapace width varied from 28 to 52 mm. This crab species can spawn during most of the year in the canal water, with a peak during late spring and early winter. The fecundity of ovigerous females ranged between 2349 and 13600 eggs with a mean of 5494 ± 1486 eggs. Female crabs that reached sexual maturity exhibited a minimum carapace width varying between 22 and 46 mm, and fifty percentage of all ovigerous females showed a carapace width of 36 mm. 相似文献
70.
The frequency and characteristics of highly thermophilic bacteria in cool soil environments 总被引:4,自引:0,他引:4
Following enrichment at 70 degrees C and 80 degrees C, five highly thermophilic aerobic eubacteria have been isolated from cool soil environments. These organisms show a temperature range for growth of 40-80 degrees C and have optimal and very high growth rates around 70 degrees C with generation times less than 30 min. All isolates are narrow rods, which stain Gram-negative, but have a Gram-positive cell wall structure and only one of five isolates is a spore former. All cultures contain a small proportion of previously unreported extremely long flexuous rods, which can be seen to divide eventually. Biochemical testing of five strains reveals a significant ability to utilize alkanes and some aromatic hydrocarbons. Using polymerase chain reaction (PCR) and restriction fragment length polymorphism (RFLP) of 16S rDNA the five strains were differentiated into three categories, which paralleled the biochemical results. 16S rDNA sequences showed high similarity with thermophilic Bacillus species now reclassified as Geobacillus. These bacteria are present in high numbers in apparently all soils and the question is raised of how these organisms, which are apparently unable to grow at the temperatures experienced in these cool soils, are so prominent. 相似文献