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971.
The control of wettability on a diamond-like carbon (DLC) thin film was carried out by exposing the film to synchrotron radiation (SR) ranging 50–1000 e V under perfluorohexane (C6F14) gas atmosphere. The contact angle of the DLC surface with a water droplet was found to increase from 73° to 114° by the SR irradiation under C6F14 gas atmosphere. The chemical components variations of the DLC surface were studied using X-ray photoelectron spectroscopy and the modified DLC film with F was studied using near-edge X-ray absorption fine structure spectroscopy. By mounting the new sample holder for the parallel SR irradiation, we succeeded in preventing secondary reaction of deposited material and controlling the contact angle of the fluorocarbon modified DLC surface.  相似文献   
972.
Catalytically active lipase was synthesized using Escherichia coli S30 extract from the signal-deleted lipL gene (lipL) in the presence of its N-terminal hydrophobic fragment-truncated modulator (rLimL) that was purified from the overexpressing E. coli cells. The specific activity of the lipase thus synthesized was 125 times higher than that of the purified one from Pseudomonas sp. 109. No lipase activity was detected in the absence of rLimL, even though the lipase protein itself was synthesized. Active lipase was also produced in vitro by coexpression of rlipL and the modulator gene (rlimL), although a much smaller amount of the lipase was formed. In the absence of rLimL, aggregates of the lipase were formed during its folding process. The addition of rLimL proportionally raised both lipase solubility and enzyme activity. An unstable but high activity peak of the lipase was found during its folding process.  相似文献   
973.
Among the components used in a wind turbine the blade is the most damageable component for fatigue caused by atmospheric turbulence. Therefor it is necessary to understand the stresses which are occurring on the operating wind turbine blade. We installed a prototype 500 kW wind turbine developed by the NEDO (New Energy and industrial technology Development Organization) in Tappi Wind Park where is very complex terrain, to study its performance, reliability and durability. Some measurements and data analysis of the blade stress have been done. In this paper, some results of the stress measurement are presented.  相似文献   
974.
Stress, a factor that affects appetite in our daily lives, enhances or suppresses appetite and changes palatability. However, so far, the mechanisms underlying the link between stress and eating have not been fully elucidated. Among the peripherally produced appetite-related peptides, ghrelin is the only orexigenic peptide, and abnormalities in the dynamics and reactivity of this peptide are involved in appetite abnormalities in various diseases and psychological states. This review presents an overview of the research results of studies evaluating the effects of various stresses on appetite. The first half of this review describes the relationship between appetite and stress, and the second half describes the relationship between the appetite-promoting peptide ghrelin and stress. The effects of sex differences and aging under stress on appetite are also described.  相似文献   
975.
We studied efficacy and safety of sulbactam/cefoperazone (SBT/CPT) in the treatment of biliary tract infections in hospitalized patients at 26 hospitals from February 1993 to March 1995. Secondary to dropout, 273 out of 338 patients entered in the study were evaluated, 127 patients with cholecystitis, 132 patients with cholangitis, and 14 patients with liver abscesses. Of these, 93 patients (34.1% had malignancy as an underlying disease. SBT/CPZ had an efficacy of 79.9% (218 patients; excellent: 52, good: 166), with the efficacy in patients with cholecystitis, cholangitis and liver abscess at 89.0% (113 patients), 77.3% (102 patients and 21.4% (3 patients), respectively. A significant difference (p < 0.05) was observed in the efficacy rates of patients with (59 patients [63.4%]) and without malignancy (159 patients [88.3%]). A total of 84 strains were isolated from bile specimens of 53 patients, and the major isolates were Escherichia coli, Pseudomonas aeruginosa and Enterococcus spp. Two or more bacterial strains were isolated simultaneously in 20 patients. Mild or moderate side effect (allergic reaction including rash etc.) were noted in 4 patients (1.18%), and laboratory abnormalities (increased GOT, etc.) were in 16 patients (4.71%) out of the total 338 patients. This study clearly demonstrated that SBT/CPZ retains its excellent clinical efficacy and safety profile, throughout its use over the past decade.  相似文献   
976.
Gastric inhibitory polypeptide (GIP) potently stimulates insulin secretion from pancreatic islets in the presence of glucose as an incretin. Because the insulinotropic effect of GIP is reduced in NIDDM, it should be clarified whether defects in the GIP receptor gene contribute to the impaired insulin secretion in NIDDM. Using genomic DNA samples from Japanese NIDDM and non-NIDDM subjects, we have investigated the entire coding region of the GIP receptor gene by polymerase chain reaction-single strand conformational polymorphism (PCR-SSCP). We have identified two missense mutations, Gly198-->Cys (Gly198Cys) in exon 7 and Glu354-->Gln (Glu354Gln) in exon 12. Investigation of the function of GIP receptor with either of these mutations reveals a half-maximal stimulation value of GIP-induced cAMP response in Chinese hamster ovary cells expressing the GIP receptor with Gly198Cys of 6.3 +/- 1.2 x 10(-10) mol/l (n = 3), which was considerably higher than that of the normal GIP receptor, 9.4 +/- 3.8 x 10(-12) mol/l GIP (n = 3), whereas that of the GIP receptor with Glu354Gln was not significantly different from that of the normal GIP receptor. To assess the possible role of the GIP receptor gene in genetic susceptibility to NIDDM, we have examined the allelic frequencies of Gly198Cys and Glu354Gln in NIDDM and control subjects. Association studies show no relationship between NIDDM and either of the two mutations.  相似文献   
977.
After immobilization of anaerobes on carbon felt in a fluidized-bed anaerobic digester at an ammonium concentration of 500 mg N/l, the results of real-time PCR analysis indicated that the cell densities of the immobilized methanogens and bacteria increased compared with those of the free-living methanogens and bacteria in the original anaerobically digested sewage sludge, respectively. The results of the clone analysis of the original sludge suggested that the major methanogens were Methanosaeta sp. and the members of the order Methanomicrobiales, and that after immobilization, these were changed to Methanobacterium and Methanosarcina sp. The results of real-time PCR analysis also showed that the ratio of the Methanosaeta sp. in the methanogenic archaea decreased from 58.2% to 0.3% after the immobilization. Methane production decreased at ammonium concentrations of greater than 6000 mg N/l. The results of real-time PCR analysis indicated that the cell density of the immobilized archaea decreased at ammonium concentrations of greater than 3000 mg N/l. On the other hand, the cell density of the immobilized bacteria did not decrease at an ammonium concentration of 6000 mg N/l, but decreased at that of 9000 mg N/l. The major methanogenic clones immobilized on the carbon felt at an ammonium concentration of 3000 or 6000 mg N/l were Methanobacterium sp. The present results indicated that methanogens were relatively more sensitive to ammonium than bacteria.  相似文献   
978.
The minimum size of a closed nano-space in which cells can survive was determined using 4-nl nanowells. One or two cells could divide in the nanowell. Our results suggest that the cell division activity in the nano-space is determined by the conflict between intercellular effects and consumption of substrates.  相似文献   
979.
980.
Atherosclerotic plaque with central depression (depressed lesion) may indicate regression of atherosclerosis in the aorta. Aortic depressed lesions have a solitary elevated area of plaque with a sharply-bordered roung depression in its center and no area ulceration. This may be interpretable as a sign of regression of atherosclerosis. To clarify the pathogenesis of depressed lesion, we studied clinical risk factors such as hypercholesterolemia in patients with depressed lesions that were confirmed at autopsy. The patients were divided into 3 groups according to their total cholesterol level at autopsy: a high-risk group (> or = 220 mg/dl), a moderate-risk group (180-220 mg/dl), and a low-risk group (< or = 180 mg/dl). Depressed lesions were found in 16.4% of those in the high-risk group, in 14.6% of those in the moderate-risk group and in 69.0% of those in the low-risk group. Severe aortic atherosclerosis was found in 69.8% of the patients; 50.9% of those with severe disease were in the-low risk group. Depressed lesions were also found in those with low levels of low-density lipoprotein cholesterol (< or = 140 mg/dl), 58.8% of whom were found to have severe atherosclerosis. There was no relationship between total cholesterol level and the presence of depressed lesions. However, a clinical prevention trial may result in sufficient control of ahterosclerosis among those in the high-risk group and may also lead to regression of aortic lesions.  相似文献   
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