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101.
BACKGROUND/AIMS: The hypothesis that profound acid suppression might prevent clot lysis and thus benefit patients with a non-bleeding visible vessel has not been confirmed. Omeprazole can suppress gastric acid remarkably and may be beneficial for patients with peptic ulcer bleeding. METHODOLOGY: Fifty-two patients with a non-bleeding visible vessel at the ulcer base were enrolled and randomized into four groups (N = 13 in each group). In the cimetidine group, the patients received cimetidine 300 mg i.v. bolus followed by 300 mg i.v. every 6 hr during hospitalization. In the heater probe thermocoagulation + cimetidine group, the patients received heater probe thermocoagulation and cimetidine 300 mg i.v. bolus followed by 300 mg i.v. every 6 h during hospitalization. In the omeprazole q.d. group, the patients received omeprazole 40 mg i.v. bolus followed by 40 mg i.v. daily for two days. In the omeprazole q 12 h group, the patients received omeprazole 40 mg i.v. bolus followed by 40 mg i.v. every 12 h for two days. A 24 hr intragastric pH was recorded for every case. RESULTS: The mean 24 hr intragastric pH were higher in the omeprazole q.d. (mean 5.8) and the omeprazole q 12 h groups (mean 6.4) than in the cimetidine (mean 4.3) and the heater probe thermocoagulation + cimetidine groups (mean 4.9) (p < 0.05). Rebleeding occurred in 5, 2, 2 and 2 patients in the cimetidine, heater probe thermocoagulation + cimetidine, omeprazole q.d., and omeprazole q 12 h groups, respectively (p > 0.05). Volume of blood transfusion and number of days in hospital were not statistically different among the four groups. CONCLUSIONS: Omeprazole can remarkably suppress gastric acid when it is compared to that of the H2 receptor blocker. Patients with a non-bleeding visible vessel using omeprazole do not exhibit a decrease in the rebleeding rate as compared with those patients using cimetidine. 相似文献
102.
The eukaryotic DnaJ homologs form a family of proteins with diverse functions. One member of the family, the Saccharomyces cerevisiae gene zuotin, was isolated for its ability to bind Z-DNA. Here, we have isolated a mouse cDNA called ZRF1 (for zuotin-related factor1) with significant homology to zuotin. The DnaJ domain and candidate phosphorylation sites of zuotin and ZRF1 are highly conserved. ZRF1 gene is localized on chromosome 5. The structural similarity of zuotin and ZRF1 suggests conservation of function of this DnaJ subfamily. 相似文献
103.
Rabbit sarcoplasmic reticulum does contain trace amounts of gangliosides, and the main species is GM3. Incorporation of GM3 into the SR vesicles or addition of it to the soybean phospholipid used for reconstitution of proteoliposomes obviously increased ATP hydrolysis, as well as, Ca2+ uptake activity of sarcoplasmic reticulum Ca(2+)-ATPase. Conformation changes of Ca(2+)-ATPase induced by GM3 were also observed by circular dichroism, intrinsic fluorescence and fluorescence quenching measurements. 相似文献
104.
Der-Fang Shiau 《Expert systems with applications》2011,38(1):235-248
The timetabling problem at universities is an NP-hard problem concerned with instructor assignments and class scheduling under multiple constraints and limited resources. A novel meta-heuristic algorithm that is based on the principles of particle swarm optimization (PSO) is proposed for course scheduling problem. The algorithm includes some features: designing an ‘absolute position value’ representation for the particle; allowing instructors that they are willing to lecture based on flexible preferences, such as their preferred days and time periods, the maximum number of teaching-free time periods and the lecturing format (consecutive time periods or separated into different time periods); and employing a repair process for all infeasible timetables. Furthermore, in the original PSO algorithm, particles search solutions in a continuous solution space. Since the solution space of the course scheduling problem is discrete, a local search mechanism is incorporated into the proposed PSO in order to explore a better solution improvement. The algorithms were tested using the timetabling data from a typical university in Taiwan. The experimental results demonstrate that the proposed hybrid algorithm yields an efficient solution with an optimal satisfaction of course scheduling for instructors and class scheduling arrangements. This hybrid algorithm also outperforms the genetic algorithm proposed in the literature. 相似文献
105.
Song-Hiang Chia Kuo-Lan Su Sheng-Ven Shiau Ting-Li Chien 《Artificial Life and Robotics》2011,16(1):10-15
This article describes a multilevel multisensor-based security system that has multiple interfaces to be applied in an intelligent
home. The security system contains four levels. There is a passive detection level, an active detection level, a system supervising
level, and a remote supervising level. The control unit of these passive modules is a HOLTEK microchip. Each passive module
has two different interfaces (wireless RF and voice). These modules can use a voice to alarm users than an event has occurred,
and can transmit the real-time status and image signal to the active detection level and the system’s supervising level via
the wireless RF interface. The active detection level can communicate with other levels via the wireless RF interface or the
wireless Internet. The remote supervising level, the supervising level, and the active detection level can communicate with
other levels via the wireless Internet. The status of these modules can also be displayed on the monitor of the supervising
computer. Finally, we present some experimental results using passive and active detection modules in the security system. 相似文献
106.
A new separation technique called stripping crystallization (SC) is applied for purification of a mesitylene/pseudoumene mixture. SC combines distillation and crystallization to produce pure crystals due to the three‐phase equilibrium. The experiments demonstrate that a batch SC operation can purify pseudoumene from 85 % to 95 % for the pseudoumene‐rich mixture with a recovery rate of 51 % while it can only purify mesitylene from 85 % to 88 % for the mesitylene‐rich mixture with a recovery rate of 34 %. Compared to azeotropic distillation, SC is a clean separation technology as no chemicals are added. SC can be continued until the liquid phase is completely eliminated and only pure crystals remain in the feed. Compared to conventional crystallization, filtration or centrifugation is not needed to separate the solid crystals from the mother liquor since no mother liquor is present together with the crystals. In addition, crystal washing is not required since no impurities adhere to the crystal surfaces at the end of operation. 相似文献
107.
Water-soluble fluorescent hyperbranched poly(amido acids) (HBPAAs), based on wholly aliphatic structures were prepared through direct self-condensation of N-(3-aminopropyl) diethano succinate amine (APDESA, AB2 monomer) in the presence of N,N-dicyclohexylcarbodiimide (DCC) as a condensation agent. The resulting HBPAAs were soluble in water, DMF and THF, and the structure of synthesized AB2 monomer and polymers was confirmed by IR, 1H, and 13C NMR measurements. TEM image indicated that the HBPAAs self-assembled in H2O to form a spherical micelle with a diameter ranging from 30 to 50 nm. A significant pH-dependent profile of fluorescent intensity in the pH range from 3 to 10 was observed, wherein pH 4 provided a critical jump as the solution pH was increased. Further increasing the pH to 10 decreased the fluorescence because of partial hydrolysis. Strong fluorescence emission was observed at 395 nm in aqueous media and the fluorescence quantum yields are to 23%. These amphiphilic HBPAAs, with excellent water-solubility, void-rich space, multiple functional peripheries and high blue fluorescence, have potential uses as tracing nanocarriers and molecular-level containers. 相似文献
108.
CD8+ T Cell-Induced Expression of Tissue Inhibitor of Metalloproteinses-1 Exacerbated Osteoarthritis
Jeng-Long Hsieh Ai-Li Shiau Che-Hsin Lee Shiu-Ju Yang Bih-O Lee I-Ming Jou Chao-Liang Wu Shun-Hua Chen Po-Chuan Shen 《International journal of molecular sciences》2013,14(10):19951-19970
Despites the fact that T cells are involved in the pathogenesis of osteoarthritis (OA) little is known about the roles of CD8+ T cells in this disease. We investigated the effects of CD8+ T cells and the expression of tissue inhibitor of metalloproteinases 1 (TIMP-1) on joint pathology. Using anterior cruciate ligament-transection (ACLT), OA was induced in mice. The knee joints were histologically assessed for manifestations of OA. The CD8+ T cells from splenocytes and synovium were flow-cytometrically and immunochemically evaluated, respectively. Local expression of TIMP-1, matrix metalloproteinase (MMP)-13, and VEGF were examined. Cartilage degeneration was slower in CD8+ T cell knockout mice than in control mice. CD8+ T cells were activated once OA was initiated and expanded during OA progression. More CD8+ T cells from splenocytes expressed TIMP-1 in ACLT-group mice than in Sham-group mice. The number of TIMP-1-expressing CD8+ T cells in OA mice correlated with the disease severity. TIMP-1 expression in cartilage was co-localized with that of MMP-13 and VEGF. TIMP-1 protein was detected in synovium in which angiogenesis occurred. During the pathogenesis of OA, the expression of TIMP-1, VEGF and MMP-13 accompanying with CD8+ T cells activation were increased. Furthermore, inhibiting the expression of TIMP-1 in joints could retard the progression of OA. 相似文献
109.
Phenol/dicyclopentadiene adducts were prepared from the BF3‐catalyzed reaction of p‐nonylphenol and dicyclopentadiene at molar ratios of 2 : 1 and 3 : 2. These dicyclopentadiene‐derived novolac products contain tricyclodecane and multiple phenol functionalities. In curing with diglycidyl ether of bisphenol A, the polymer properties were compared with those cured with formaldehyde novolac or Jeffamine D‐400 amine. When p‐nonylphenol/dicyclopentadiene adducts were mixed with other commercially available curing agents such as Jeffamine D‐400 amine, the tricyclodecane functionality was introduced into the resulting epoxy network. The flexibility of the cured resin was improved due to the presence of the tricyclodecane moiety in the polymer structure. © 1999 John Wiley & Sons, Inc. J Appl Polym Sci 74: 2196–2206, 1999 相似文献
110.
Shu-Chen Cheng Der-Fang Shiau Yueh-Min Huang Yen-Ting Lin 《Expert systems with applications》2009,36(1):852-860
Most publications in shop scheduling area focus on the static scheduling problems and seldom take into account the dynamic disturbances such as machine breakdown or new job arrivals. Motivated by the computational complexity of the scheduling problems, genetic algorithms (GAs) have been applied to improve both the efficiency and the effectiveness for NP-hard optimization problems. However, a pure GA-based approach tends to generate illegal schedules due to the crossover and the mutation operators. It is often the case that the gene expression or the genetic operators need to be specially tailored to fit the problem domain or some other schemes may be combined to solve the scheduling problems. This study presents a GA-based approach combined with a feasible energy function for multiprocessor scheduling problems with resource and timing constraints in dynamic real-time scheduling. Moreover, an easy-understood genotype is designed to generate legal schedules. The results of the experiments demonstrate that the proposed approach performs rapid convergence to address its applicability and generate good-quality schedules. 相似文献