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941.
Ong ME Chan YH Teo J Saroja S Yap S Ang PH Lim SH 《The American journal of emergency medicine》2008,26(4):433-438
Objectives
The hair apposition technique (HAT) is a new method of closing scalp lacerations in which hairs on either side of the wound are twisted together and secured with a tissue adhesive. We aimed to compare the effectiveness, complications, and benefits of HAT performed by nurses or doctors in a randomized, prospective trial.Methods
We conducted the study in the ED from November 2002 to February 2005. Subjects were randomized to receive HAT either by doctors or nurses. All wounds were evaluated 7 days later. The outcomes wound infection, wound healing, bleeding, and overall complications were measured, setting ±5% in the differences of the outcomes between the doctors and nurses as equivalence.Results
There were 88 and 76 patients in the doctor and nurse groups, respectively. There were no significant differences in all short-term outcomes between the doctors and nurses except for length of the procedure. The doctors had a shorter mean duration of procedure than the nurses (9.0 ± 5.6 vs 12.8 ± 7.5 minutes, P = .001).Conclusion
The HAT can be safely performed by trained nurses with equivalent outcomes as doctors. 相似文献942.
943.
The aim of this study was to clarify the anti-inflammatory mechanism of apigenin. Apigenin inhibited the collagenase activity involved in rheumatoid arthritis (RA) and suppressed lipopolysaccharide (LPS)-induced nitric oxide (NO) production in a dose dependent manner in RAW 264.7 macrophage cells. Pretreatment with apigenin also attenuated LPS-induced cyclooxygenase-2 (COX-2) expression. In addition, apigenin profoundly reduced the tumor necrosis factor-alpha (TNF-alpha)-induced adhesion of monocytes to HUVEC monolayer. Apigenin significantly suppressed the TNF-alpha-stimulated upregulation of vascular cellular adhesion molecule-1 (VCAM-1)-, intracellular adhesion molecule-1 (ICAM-1)-, and E-selectin-mRNA to the basal levels. Taken together, these results suggest that apigenin has significant anti-inflammatory activity that involves blocking NO-mediated COX-2 expression and monocyte adherence. These results further suggest that apigenin may be useful for therapeutic management of inflammatory diseases. 相似文献
944.
In this study we investigated the effects of constituents of Amomum xanthioides (AX) on gastritis in rats and on the growth of human gastric cancer cells. The ethanol extract of Amomum xanthioides significantly inhibited HCl ethanol-induced gastric lesions and the growth of Helicobacter pylori (H. pylon). The ethanol extract of AX was further fractionated with hexane, chloroform, butanol and H20. Among these fractions, oral treatment with the butanol fraction at a dose of 350 mg/kg was the most effective at preventing HCl* ethanol-induced gastric lesions. In pylorus ligated rats, the butanol fraction also decreased the volume of gastric secretion and gastric acid output. We isolated six subfractions of the butanol fraction using open column chromatography. Subfraction 4 (150 mg/kg) significantly inhibited HCl* ethanol-induced gastric lesions and gastric secretion in pylorus ligated rats. Using GC-MS we identified the constituents of subfraction 4 to be five aliphatic compounds, 1-hexadecene, 1-nonadecene, cycloeicosane, 1-octadecene and cyclotetracosane. In addition, subfraction 4 reduced cell viability in a dose-dependent manner in human gastric cancer cells (AGS, KATOIII and SNU638). It also increased intracellular Ca2+ concentration in SNU638 cells, an effect that was significantly inhibited by dantrolene, a Ca2+ release blocker. Moreover, dantrolene significantly inhibited subfraction 4-induced cytotoxicity. Taken together, these results suggest that subfraction 4 of the butanol extract of AX has an anti-gastritic effect in rats and is cytotoxic to human gastric cancer cells. The mechanism of its anti-gastritic action may be associated with the inhibition of secretion of gastric acid and anti-H. pylori action. Its cytotoxicity against human gastric cancer cells may be, at least in part, mediated by intracellular Ca2+ dyshomeostasis. From these results, we suggest that AX may be useful for the treatment of gastritis and gastric cancer. 相似文献
945.
Jeong DW Kim YH Ji HY Youn YS Lee KC Lee HS 《Journal of pharmaceutical and biomedical analysis》2007,44(2):547-552
A rapid, sensitive and selective method for the determination of carvedilol in human plasma was developed using hydrophilic interaction liquid chromatography with tandem mass spectrometry (HILIC-MS/MS). Carvedilol and cisapride (internal standard) were extracted from human plasma with methyl tert-butyl ether at basic pH and analyzed on an Atlantis HILIC Silica column with the mobile phase of acetonitrile-ammonium formate (50 mM, pH 4.5) (90:10, v/v). The analytes were detected using an electrospray ionization tandem mass spectrometry in the multiple-reaction-monitoring mode. The standard curve was linear (r=0.9998) over the concentration range of 0.1-200 ng/ml. The lower limit of quantification for carvedilol was 0.1 ng/ml using 50 microl plasma sample. The coefficient of variation and relative error for intra- and inter-assay at four QC levels were 1.6-4.5% and -6.4 to 4.8%, respectively. The absolute and relative matrix effect for carvedilol and cisapride were practically absent. The extraction recoveries of carvedilol and cisapride were 81.6 and 85.2%, respectively. This method was successfully applied to the bioequivalence study of carvedilol in humans. 相似文献
946.
The purpose of this study was to investigate in vitro release property of mono-PEGylated growth hormone-releasing peptide-6 (GHRP-6) microspheres. The microspheres encapsulating native GHRP-6 or mono-PEG-GHRP-6 were prepared using the single oil-in-water emulsion solvent evaporation method. In vitro release study was performed in 0.1M phosphate buffer, pH 7.4, containing 0.02% Tween 80 and sodium azide at 37 or 55 degrees C. The mono-PEG-GHRP-6 microspheres showed a lower initial burst compared with native GHRP-6 microspheres and zero-order release profile for a 1-month period. The release period was dependent on the PEG size attached to the GHRP-6 with more rapid drug release being observed with the smaller PEG size. This study suggests that PEGylated peptide has good potential as a source for a sustained release microsphere delivery system. 相似文献
947.
948.
Quantitative structure-activity relationship (QSAR) and quantitative structure-property relationship (QSPR) models have been extensively used for predicting compounds of specific pharmacodynamic, pharmacokinetic, or toxicological property from structure-derived physicochemical and structural features. These models can be developed by using various regression methods including conventional approaches (multiple linear regression and partial least squares) and more recently explored genetic (genetic function approximation) and machine learning (k-nearest neighbour, neural networks, and support vector regression) approaches. This article describes the algorithms of these methods, evaluates their advantages and disadvantages, and discusses the application potential of the recently explored methods. Freely available online and commercial software for these regression methods and the areas of their applications are also presented. 相似文献
949.
Chen X Li H Yap CW Ung CY Jiang L Cao ZW Li YX Chen YZ 《Cardiovascular & hematological agents in medicinal chemistry》2007,5(1):11-19
Computational methods have been explored for predicting agents that produce therapeutic or adverse effects in cardiovascular and hematological systems. The quantitative structure-activity relationship (QSAR) method is the first statistical learning methods successfully used for predicting various classes of cardiovascular and hematological agents. In recent years, more sophisticated statistical learning methods have been explored for predicting cardiovascular and hematological agents particularly those of diverse structures that might not be straightforwardly modelled by single QSAR models. These methods include partial least squares, multiple linear regressions, linear discriminant analysis, k-nearest neighbour, artificial neural networks and support vector machines. Their application potential has been exhibited in the prediction of various classes of cardiovascular and hematological agents including 1, 4-dihydropyridine calcium channel antagonists, angiotensin converting enzyme inhibitors, thrombin inhibitors, AchE inhibitors, HERG potassium channel inhibitors and blockers, potassium channel openers, platelet aggregation inhibitors, protein kinase inhibitors, dopamine antagonists and torsade de pointes causing agents. This article reviews the strategies, current progresses and problems in using statistical learning methods for predicting cardiovascular and hematological agents. It also evaluates algorithms for properly representing and extracting the structural and physicochemical properties of compounds relevant to the prediction of cardiovascular and hematological agents. 相似文献
950.
Suh KT Moon KP Lee HS Lee CK Lee JS 《Archives of orthopaedic and trauma surgery》2009,129(10):1309-1315
Purpose Bipolar hemiarthroplasty (BH) is one of the commonly performed orthopedic procedures for the treatment of displaced fractures
of the femoral neck. However, despite the common use of the BH, little has been written on preoperative planning for this
operation. The purpose of this study was to assess the neglected subject which is about the cognition of the femoral head
cartilage in planning a BH.
Methods We reviewed a group of 62 consecutive patients in whom cemented BH had been performed by one surgeon. A total of 31 patients
underwent BH with consideration of the femoral head cartilage thickness in preoperative planning. The anteroposterior radiographs
of this group were compared to those of a group of 31 patients who underwent BH without consideration of the femoral head
cartilage thickness in preoperative planning. We measured the limb length and offset with reference to the normal contralateral
hip and the cartilage thickness of the hip joints postoperatively.
Results There were significant reduction in the limb-length discrepancy (LLD) (mean 0.4 mm lengthening compared with 1.6 mm shortening;
P < 0.001) and improvement of the femoral offset ratios of the operated hips to the normal contralateral hips (mean 99.9% compared
with 96.8%; P = 0.032) in the group of patients with consideration of the femoral head cartilage thickness in preoperative planning.
Conclusions The femoral head cartilage should be considered when determining the level of femoral neck resection in order to reduce postoperative
LLD when planning a bipolar hemiarthroplasty. Accurate and careful preoperative planning can result in balanced hip reconstruction
by equalizing limb lengths and restoring the offsets. 相似文献