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71.
The utility of a pre-optimized kit for random amplified polymorphic DNA (RAPD) was assessed in typing diverse strains of Candida albicans from epidemiologically unrelated inpatients (interpatient analysis) and in detecting clonal variations that maybe present within individual patient isolates (intrapatient analysis). Stool samples from inpatients were cultured on Inhibitory Mold agar. Nine individual colonies from all patients with > or =9 colonies of C. albicans (n = 18) were selected, frozen, and karyotyped using CHEF genomic DNA plug kits and CHEF-DRIII. Each of the selected colonies was then analyzed by RAPD, utilizing the selected kit, with 6 primers. Interpatient analysis revealed 9 karyotypes and 17 RAPD composites. RAPD discrimination was significantly better (p < 0.001). Intrapatient analysis revealed 34 (21%) and 33 (20.4%) variants among 162 colonies tested by RAPD and karyotyping, respectively. The results were discordant in 25 variants, all with differences of 1-3 bands. These results illustrate that this pre-optimized kit for RAPD provides excellent discrimination of genetically unrelated strains. Its performance in delineating subtle clonal differences was comparable with karyotyping; both methods failed to detect all minor genetic variations. The ease of use and quick turnaround time of this kit offer a practical and reliable method for typing diverse strains of C. albicans, but may be inadequate for assessing microevolution.  相似文献   
72.
The aim of this study is to follow the thermodynamic behaviour of Na+ ions, acting as natural counterions of DNA, in the presence of divalent metal ions, by using the23Na NMR technique. With the help of the23Na entropy of fluctuations concept introduced by Lenk, we propose the following decreasing sequence: Mg++, Zn++, Cd++, Mn++, and Cu++, for the magnitude of divalent metal ions interactions with DNA phosphate sites.  相似文献   
73.
Cloud computing is a relatively recent computing paradigm that is often the answer for dealing with large amounts of data. Tenants expect the cloud providers to keep supplying an agreed upon quality of service, while cloud providers aim to increase profits as it is a key ingredient of any economic enterprise. In this paper, we propose a data replication strategy for cloud systems that satisfies the response time objective for executing queries while simultaneously enables the provider to return a profit from each execution. The proposed strategy estimates the response time of the queries and performs data replication in a way that the execution of any particular query is still estimated to be profitable for the provider. We show with simulations that how the proposed strategy fulfills these two criteria.  相似文献   
74.
Abstract: In NG 108–15 clonal cells, extracellular application of micromolar concentrations of serotonin [5-hydroxy-tryptamine (5-HT)] and substance P induces the opening of a cation permeability monitored by the influx of [14C]-guanidinium. The serotoninergic component of this cation permeability Is linked to 5-HT3 receptor activation, whereas the substance P component probably involves an “N-terminal-dependent substance P receptor.” In this study, [14C]guanidinium influx triggered by 1 μM 5-HT plus 10 μM substance P was shown to be insensitive to tetrodotoxin, verapamil, diltiazem, nimodipine, and ω-conotoxin, as expected from a process independent of voltage-sensitive sodium and calcium channels. In contrast, [14C]guanidinium influx was inhibited by millimolar concentrations of extracellular calcium and by the chelation of intracellular calcium by bis-O-aminophenoxyethanetetraacetic acid. The inhibition by extracellular calcium apparently involved a competition between the divalent cation and [14C]guanidinium for the same channel. When NG 108–15 cells were exposed to X537A, an ionophore that specifically induces release of calcium from intracellular stores, [14C]guanidinium uptake was markedly increased even in the absence of 5-HT and/or substance P. Conversely, [14C]guanidinium influx due to the latter substances could be reversibly and dose-dependently blocked by various drugs that possess calmodulin-antagonizing properties. These results strongly suggest that the cation permeability opened by 5-HT and substance P in NG 108–15 cells involves a calcium/calmodulin-dependent process. However, as the phosphodiesterase inhibitor isobutylmethylxanthine, the nitric oxide synthase inhibitor A/monomethylarginine, the protein kinase C inhibitor staurosporine, and the protein kinase C activator 12-O-tetradeca-noylphorbol 13-acetate did not alter [14C]guanidinium influx in NG 108–15 cells exposed to 5-HT and substance P., this process probably does not involve the calcium-dependent nitric oxide pathway and protein kinase C activation.  相似文献   
75.
The metabolic syndrome, as defined by the International Diabetes Federation, was investigated in five large, extended, highly consanguineous, healthy Omani Arab families of a total of 1277 individuals. Heritability (h2) of the phenotypic abnormalities that make up the syndrome and other related traits was estimated by variance decomposition method using SOLAR software. The overall prevalence of the syndrome was 23%. The prevalence of abnormalities making the syndrome in a descending order were: obligatory waist circumference, hypertension, raised fasting blood glucose, low serum high-density lipoprotein (HDL), and raised serum triglycerides (TGs). Highly significant, but widely spread, h2 values were obtained for: height (0.68), weight (0.68), BMI (0.68), serum HDL (0.63), serum leptin (0.55), percentage body fat (0.53), total serum cholesterol (0.53), fasting serum insulin (0.51), homeostasis model assessment-insulin resistance index (0.48), serum TG (0.43), waist circumference (0.40), diastolic blood pressure (0.38), and 2-hour glucose level (0.17), whereas for the metabolic syndrome itself, h2 was 0.38. The wide spread of h2 results (0.07 to 0.68) indicates that some determinants, such as weight, BMI, and HDL level, are under significant genetic influence among the Omani Arabs. Other determinants such as insulin resistance, abdominal obesity, diastolic blood pressure, and TG levels seem to be more environmentally driven.  相似文献   
76.
Probiotics and Antimicrobial Proteins - Lactobacilli strains are considered as a preventive means for treatment of vaginal infections or post-antibiotic treatment to repopulate the vaginal mucosa....  相似文献   
77.
78.
Clathrin-dependent endocytosis of Na(+),K(+)-ATPase in response to dopamine regulates its catalytic activity in intact cells. Because fission of clathrin-coated pits requires dynamin, we examined the mechanisms by which dopamine receptor signals promote dynamin-2 recruitment and assembly at the site of Na(+),K(+)-ATPase endocytosis. Western blotting revealed that dopamine increased the association of dynamin-2 with the plasma membrane and with phosphatidylinositol 3-kinase. Dopamine inhibited Na(+),K(+)-ATPase activity in OK cells and in those overexpressing wild type dynamin-2 but not in cells expressing a dominant-negative mutant. Dephosphorylation of dynamin is important for its assembly. Dopamine increased protein phosphatase 2A activity and dephosphorylated dynamin-2. In cells expressing a dominant-negative mutant of protein phosphatase 2A, dopamine failed to dephosphorylate dynamin-2 and to reduce Na(+),K(+)-ATPase activity. Dynamin-2 is phosphorylated at Ser(848), and expression of the S848A mutant significantly blocked the inhibitory effect of dopamine. These results demonstrate a distinct signaling network originating from the dopamine receptor that regulates the state of dynamin-2 phosphorylation and that promotes its location (by interaction with phosphatidylinositol 3-kinase) at the site of Na(+),K(+)-ATPase endocytosis.  相似文献   
79.
80.
Microbial prospecting technique was applied in El Hajeb oilfield, Tunisia for potential hydrocarbon resource exploration by examining the anomalous abundance of hydrocarbon oxidizing bacteria. The method depends on the seepage of light gaseous hydrocarbons such as C1 – C5 from the petroleum pools to the shallow surface giving the reasonable conditions to the development of highly specialized bacterial population. A total of 51 soil samples were collected from 1.5 m depth. Bacterial counts for n-propane utilizing bacteria ranged between nil and 2.44?×?105?cfu/gm. The light gaseous hydrocarbons analysis showed that their concentrations were 102, 55, 41, 20, 21, 19, 10 and 141 ppb for C1, C2, C3, iC4, nC4, iC5, nC5 and ΣC2+, respectively. The gas concentration maps showed the presence of dynamic hydrocarbons micro-seepage from petroleum systems. The integrated geomicrobial and adsorbed soil gas results demonstrated that the anomalous hydrocarbon zones spread in all territory which could presumably help to evaluate highpotentialareas. In conclusion, our study confirms that the use of microbial data and adsorbed gas analyses of soil samples is a low cost tool for hydrocarbon exploration. This technique has been confirmed and can be applied successfully in frontier basins.  相似文献   
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