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991.
Woo Jin Lee Chong Oon Park Seung Hwan Yoon Young Chae Chu 《Journal of Korean Neurosurgical Society》2010,48(5):461-464
The authors report a 58-year-old woman with low-grade fibromyxoid sarcoma primarily located in the right paravertebral area with extension to L4 neural foramen. The patient complained lower back pain with radiating pain along the posterolateral aspect of the right lower leg. She underwent subtotal surgical removal and Cyber Knife therapy. Diagnosis was made by strikingly characteristic microscopic appearance of a bland spindle cell sarcoma which contained numerous giant collagen rosettes and was also supported by immunohistological findings. The diagnostic image findings and literatures are reviewed and discussed. 相似文献
992.
Shina C.L. Kamerlin Pankaz K. Sharma Zhen T. Chu Arieh Warshel 《Proceedings of the National Academy of Sciences of the United States of America》2010,107(9):4075-4080
One of the best systems for exploring the origin of enzyme catalysis has been the reaction of ketosteroid isomerase (KSI). Studies of the binding of phenolates to KSI have been taken as proof that the electrostatic preorganization effect only makes a minor contribution to the binding of the real, multiring, transition state (TS). However, our simulation study has determined that the difference between the phenolates and the TS arises from the fact that the nonpolar state of the phenolate can rotate freely relative to the oxyanion hole and thus loses the preorganization contribution. A recent study explored the reactivity of both small and multiring systems and concluded that their similar reactivity contradicts our preorganization idea. Herein, we establish that the available experiments in fact provide what is perhaps the best proof and clarification of the preorganization idea and its crucial role in enzyme catalysis. First, we analyze the binding energy and the pKa of equilenin and identify direct experimental evidence for our prediction about the differential electrostatic stabilization of the large TS and the small phenolates. Subsequently, we show that the similar reactivity of the small and large systems is also due to an electrostatic preorganization effect but that this effect only appears in the intermediate state because the TS is not free to rotate. This establishes the electrostatic origin of enzyme catalysis. We also clarify the crucial importance of having a well-defined physical concept when examining catalytic effects and the need for quantitative tools for analyzing such effects. 相似文献
993.
We report a case of an 87‐year‐old woman who presented with painful erythema of her right forearm 10 days after she had been stung by a wasp on her right hand. The lesion had rapidly deteriorated during the week before presentation, and treatment with antibiotics and glucocorticoids did not improve the condition. After careful evaluation, we performed cultures from the lesion aspiration, and morphological and genetic analysis of bacteria cultures confirmed a bacterial infection with Nocardia brasiliensis. The patient recovered after 3 weeks. Primary cutaneous nocardiosis due to Nocardia spp. is relatively uncommon in clinics, but it was the distance of the lesions from the affected area of the wasp sting that has made this an even rarer case and of interest to report. 相似文献
994.
Ching-I Teng PhD Yu-Tzu Dai RN PhD Yea-Ing Lotus Shyu RN PhD May-Kuen Wong PhD MD Tsung-Lan Chu RN MSN & Ying-Huang Tsai MD 《Journal of nursing scholarship》2009,41(3):301-309
Purpose: To examine how professional commitment influences patient safety and patient-perceived care quality.
Design: Investigators for this study used a cross-sectional design with questionnaires. A total of 348 pairs of nurses and inpatients were contacted at two medical centers in Taiwan during the period from August 2007 to January 2008, yielding 284 pairs of completed questionnaires.
Methods: Frequencies of six adverse patient events were used to measure patient safety; and the Service Quality Scale was used to measure patient-perceived care quality. Four items of the Professional Commitment Questionnaire were used to measure professional commitment. Regressions were used for the analyses.
Findings: Professional commitment positively influenced overall patient safety (ß=.19, p =.00) and overall patient-perceived care quality (ß=.13, p =.03). Furthermore, professional commitment positively influenced all patient safety indicators (ß≥.12, p ≤.04), except frequency of nosocomial infections, the coefficient of which reached borderline significance (ß=.11, p =.07). Professional commitment also positively influenced care quality in terms of responsiveness (ß=.16, p =.01) and empathy (ß=.14, p =.03).
Conclusions: Professional commitment may enhance patient safety and patient-perceived care quality.
Clinical Relevance: This study indicates that nurse professional commitment can enhance patient safety and patient-perceived care quality. 相似文献
Design: Investigators for this study used a cross-sectional design with questionnaires. A total of 348 pairs of nurses and inpatients were contacted at two medical centers in Taiwan during the period from August 2007 to January 2008, yielding 284 pairs of completed questionnaires.
Methods: Frequencies of six adverse patient events were used to measure patient safety; and the Service Quality Scale was used to measure patient-perceived care quality. Four items of the Professional Commitment Questionnaire were used to measure professional commitment. Regressions were used for the analyses.
Findings: Professional commitment positively influenced overall patient safety (ß=.19, p =.00) and overall patient-perceived care quality (ß=.13, p =.03). Furthermore, professional commitment positively influenced all patient safety indicators (ß≥.12, p ≤.04), except frequency of nosocomial infections, the coefficient of which reached borderline significance (ß=.11, p =.07). Professional commitment also positively influenced care quality in terms of responsiveness (ß=.16, p =.01) and empathy (ß=.14, p =.03).
Conclusions: Professional commitment may enhance patient safety and patient-perceived care quality.
Clinical Relevance: This study indicates that nurse professional commitment can enhance patient safety and patient-perceived care quality. 相似文献
995.
本文针对必特螺旋霉素发酵主要组分异戊酰基螺旋霉素以及异戊酰基螺旋霉素Ⅲ的提高,在摇瓶培养基试验中,通过一次性添加与分批添加终浓度为15.4mmol/L的亮氨酸,发现分批添加亮氨酸可以维持效价基本不变,而总异戊酰基螺旋霉素与异戊酰基螺旋霉素Ⅲ分别由对照的31.1%和12.0%提高至46.9%和19.5%。通过分析发酵过程的有机酸以及氨基酸的变化规律,讨论了亮氨酸提高必特螺旋霉素主要组分的作用机理,同时在15L发酵罐中对分批添加亮氨酸添加效果进行了验证试验,结果表明,发酵液必特螺旋霉素组分中总异戊酰基螺旋霉素和异戊酰基螺旋霉素Ⅲ在96h分别提高至59.91%和21.45%。 相似文献
996.
JME Kovoor RD Thomas HS Chandrashekhar PN Jayakumar S Pillai SK Shankar 《Journal of Medical Imaging and Radiation Oncology》2007,51(5):406-411
Early and non‐invasive evaluation of hydatid infestation of brain and spine is of paramount importance, especially in endemic areas. We present a spectrum of imaging findings in neurohydatidosis with a brief review of literature. 相似文献
997.
Vivian Yvonne Shin William Ka Kei Wu Kent Man Chu Marcel Wing Leung Koo Helen Pui Shan Wong Emily Kai Yee Lam Emily Kin Ki Tai Chi Hin Cho 《Toxicological sciences》2007,96(1):21-29
We previously reported that nicotine promoted gastric cancer cell growth via upregulation of cyclooxygenase 2 (COX-2). In the present study, we further investigated whether beta-adrenoceptors, protein kinase C (PKC), and extracellular signal-regulated kinase-1/2 (ERK1/2) were involved in the modulation of COX-2 expression and cell proliferation by nicotine in AGS, a human gastric adenocarcinoma cell line. Results showed that nicotine dose dependently increased the phosphorylation of EKR1/2 and the expression of AP-1 subunits c-fos and c-jun. In this connection, the ERK1/2 inhibitor U0126 abrogated the upregulation of AP-1 and COX-2 as well as cell proliferation induced by nicotine. Moreover, nicotine induced the translocation of PKC-betaI from cytosol to membrane and increased the total levels of PKC expression. Inhibition of PKC by staurosporine attenuated nicotine-induced ERK1/2 phosphorylation and COX-2 expression. Furthermore, atenolol and ICI 118,551, a beta1- and beta2-adrenoceptor antagonist, respectively, reversed the stimulatory action of nicotine on the expression of PKC, ERK1/2 phosphorylation, and COX-2 together with cell proliferation. Collectively, these results suggest that nicotine stimulates gastric cancer cell growth through the activation of beta-adrenoceptors and the downstream PKC-betaI/ERK1/2/COX-2 pathway. 相似文献
998.
Dr Jalal K. Ghali S. William Tam Keith C. Ferdinand JoAnn Lindenfeld Michael L. Sabolinski Anne L. Taylor Manuel Worcel Charles L. Curry Jay N. Cohn 《Am J Cardiovasc Drugs》2007,7(5):373-380
BACKGROUND: In the A-HeFT (African-American Heart Failure Trial), treatment of African-American patients with New York Heart Association (NYHA) class III/IV heart failure (HF) with fixed-dose combination (FDC) of isosorbide dinitrate/hydralazine (I/H) reduced mortality and morbidity and improved patient reported functional status compared with standard therapy alone. OBJECTIVE: To examine the benefit of FDC I/H in subgroups based on baseline drug therapy and to investigate whether ACE inhibitors and/or angiotensin receptor antagonists (angiotensin receptor blockers) [ARBs] or beta-adrenoceptor antagonists (beta-blockers) provided additional benefit in FDC I/H-treated African-American patients with HF. STUDY DESIGN: The A-HeFT was a double-blind, placebo-controlled study enrolling 1050 patients stabilized on optimal HF therapies and with NYHA class III/IV HF with systolic dysfunction conducted during the years 2001-4 with up to 18 months follow-up. The primary endpoint was a composite of mortality, first HF hospitalization, and improvement of quality of life at 6 months. Secondary endpoints included mortality, hospitalizations, and change in quality of life. Prospective Kaplan-Meier survival analyses were used for differences between FDC I/H and placebo groups and retrospective analyses were conducted within FDC I/H-treated and placebo groups. RESULTS: Subgroup analysis for mortality, event-free survival (death or first HF hospitalization), and HF hospitalization showed that FDC I/H, compared with placebo, was effective with or without ACE inhibitors or beta-blockers or other standard medications with all-point estimates favoring the FDC I/H group. Within the placebo-treated group, beta-blockers or ACE inhibitors and/or ARBs were efficacious in improving survival (hazard ratio [HR] 0.33; p<0.0001 for [beta]-blocker use and HR 0.39; p=0.01 for ACE inhibitor and/or ARB use). However, within the FDC I/H-treated group, use of beta-blockers, but not ACE inhibitors and/or ARBs, provided additional significant benefit for survival (HR 0.44; p=0.029 and HR 0.60; p=0.34, respectively), event-free survival (HR 0.62; p=0.034 and HR 0.72; p=0.29, respectively) and the composite score of death, HF hospitalization and change in quality of life (p=0.016 and p=0.13, respectively). CONCLUSION: Based on the analysis of baseline medication use in the A-HeFT, FDC I/H was superior to placebo with or without beta-blockers or ACE inhibitor. However, beta-blockers but not ACE inhibitors and/or ARBs provided additional significant benefit in African-Americans with HF treated with FDC I/H. These analyses are hypotheses generating and their confirmation in clinical trials needs to be considered. 相似文献
999.
R Poon I Chu V E Valli L Graham A Yagminas B Hollebone G Rideout M Fingas 《Food and chemical toxicology》2007,45(10):1830-1837
Because of the accessible and renewable nature of feedstock and the potential for the reduction of harmful combustion emissions and greenhouse gases, biodiesels have received increasing interest as an alternate fuel. Oral exposure to biodiesels is a concern because of contact during refuelling, accidental ingestion and exposure through ground water contamination. Although biodiesels from various feedstock are in use commercially and experimentally, very little is known about their potential adverse effects and no data is available on their potential for ground water contamination. A study was performed on male rats following oral treatment with experimental biodiesels (dissolved in corn oil) derived from canola oil (Bio-C), soy oil (Bio-S) and fish oil (Bio-F), at 500 mg/kg body weight/day, 5 days per week, for 4 weeks. Separate groups of animals were treated with low sulfur diesel (LSD) for comparison purpose, and with corn oil alone to serve as control. The potential for ground water contamination by biodiesels was investigated by the preparation of water-accommodated fractions (WAF) followed by gas chromatographic analysis. WAF from Bio-F and Bio-S was found to have the highest level of dichloromethane extractable materials. Gas chromatographic analysis indicated that the extractable materials from biodiesels contained much higher proportion of C15-C30 materials than LSD. Increased liver weight was observed in animal treated with Bio-C, Bio-S and LSD and decreased thymus weight was found in those treated with Bio-S. Histopathological changes typical of male-rat specific hyaline-droplet nephropathy were detected in kidney tubules of animals treated with LSD, Bio-S and Bio-C. Mild adaptive changes were observed in thyroids of animals treated with LSD, Bio-S and Bio-F. Clinical chemical and biochemical changes were confined to Bio-S and LSD treated rats and included elevation in some hepatic phase-I and phase-II drug metabolizing enzymes and hepatic palmitoyl Co-A oxidase, and elevated urinary concentrations of ascorbic acid and albumin. At the given dose level of 500 mg/kg bw/day, the overall treatment-related effects of biodiesels and LSD are mild, and the severity of the treatment effects may be ranked as: LSD>Bio-S>Bio-C>Bio-F. Considered together with the presence of a higher level of water extractable materials, Bio-S may be more of a concern for potential human health than Bio-C and Bio-F in an oral exposure scenario. Further studies are needed to identify and characterize the constituents contributing to the treatment-related effects specific to these experimental biodiesels. 相似文献
1000.
BACKGROUND/AIMS: Proton-pump inhibitor-based triple therapy given over one to two weeks is currently one of the recommended regimens for eradication of Helicobacter pylori. Most of these regimens require twice daily intake of medication. The present study explored the possibility of using a one-week once-daily triple therapy in the eradication of H. pylori. METHODOLOGY: Thirty-two consecutive patients with acid-peptic disease associated with H. pylori infection (duodenal ulcer 18 patients; gastric ulcer 8 patients; duodenitis 1 patient; gastritis 5 patients) were prospectively recruited. They were given a 1-week course of lansoprazole 30 mg, clarithromycin modified-release 500 mg, and metronidazole 800 mg, all taken once daily. RESULTS: The age of these 32 patients ranged from 17-89 years with a mean of 57.5 years. Side effects occurred in 5 patients (15.6%; 95% CI: 5.3-32.8%). All patients finished the treatment and underwent a second endoscopy. Positive endoscopic finding was found in one patient (3.1%; 95% CI: 0.07-16.2%). On intent-to-treat and per protocol analysis, the eradication rate was 87.5% (95% CI: 71.0-96.5%). CONCLUSIONS: A one-week once-daily course of lansoprazole, clarithromycin modified release and metronidazole is a safe, well-tolerated, easy to comply with, and efficacious treatment for H. pylori infection. In view of the small sample size, further studies should be performed to validate its effectiveness. 相似文献