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101.
Employee commitment to the organization is a crucial issue in today's health-care market. In Iran, few studies have sought to evaluate the factors that contribute to forms of commitment. The aim of this study was to investigate the relationship between nurses' organizational commitment, work environment conditions, and life satisfaction. A cross-sectional design was utilized. Questionnaires were distributed to all the staff nurses who had permanent employment (with at least 2 years of experience in nursing) in the five hospitals affiliated to Birjand Medical Sciences University. Two hundred and fifty participants returned completed questionnaires. Most were female and married. The correlation of the total scores of nurses' affective organizational commitment and work environment conditions indicated a significant and positive relationship. Also, a statistically significant relationship was found between affective organizational commitment and life satisfaction. The implementation of a comprehensive program to improve the work conditions and life satisfaction of nurses could enhance their organizational commitment.  相似文献   
102.
Invasion of the nervous system and neuronal spread of infection are critical, but poorly understood steps in the pathogenesis of prion diseases. We have thus analyzed the internalization and signal transduction of the neurotoxic fragment of the prion protein PrP106–126 in the rat neuroblastoma cell line B104 by fluorescence microscopy and quantification by ELISA and in primary neuronal cells from mice. Phospholipase D (PLD) is known to be an enzyme involved in the regulation of secretion, endocytosis and receptor signalling. We determined the PLD activity using a transphosphatidylation assay and could show that PLD is involved in PrP106–126 internalization. The determination of receptor activity via quantification of ERK1/2 phosphorylation and cAMP level measurement verified the PrP106–126-induced signal transduction in B104 cells and primary neuronal cells. PrP106−126-induced a decrease in cAMP level in neuronal cells. These studies indicate the involvement of PLD in PrP106–126-endocytosis and mediated cellular signalling by an unidentified inhibitory G-protein-coupled receptor and may allow the development of therapeutic agents interfering with prion uptake and/or PLD function using PLD as a possible pharmaceutical target.  相似文献   
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Here, we report a simple and extremely effective method to modify a glassy carbon (GC) electrode with carbon nanotubes (CNTs) and [Mn(CH3COO)(CH3OH)2(pyterpy)]ClO4, (pyterpy = 4′-(4-pyridyl)-2,2′:6′,2′′-terpyridine) complex. The kinetics of the reaction between, the terpyridine manganese(II) complex, mediator and hydrazine has been characterized using cyclic voltammetry and rotating disk electrode voltammetry. The catalytic currents were proportional to the concentration of hydrazine giving rise to calibration curves characterized by two linear segments. The linear segment over the concentration range of 1.00 × 10−3–1.05 mM could be used with analytical purposes to determination of hydrazine with a detection limit of 0.50 μM and a sensitivity of 0.038 μA/μM. The heterogeneous rate constant, k′ for the oxidation of hydrazine at the surface of the modified electrode was determined by rotating disk electrode voltammetry using the Koutecky–Levich plot. The transfer coefficient (α) for electrocatalytic oxidation of hydrazine and the diffusion coefficient of this substance under the experimental conditions were also investigated. The resulting modified electrode retains its initial response for at least one month if stored dry in air.  相似文献   
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目的:评价利用活体异体结膜缘和羊膜移植治疗化学性眼外伤造成的角膜缘干细胞缺失的临床效果。方法:从2005-07/2007-12,本研究包括了9名男性化学性眼外伤患者(10眼)。所有患者接受了亲属活体异体结膜缘和羊膜移植,2例眼接受了睑缝术。用环孢菌素和泼尼松龙进行全身性免疫抑制。结果:在3例眼中观察到完全角膜上皮化(30%),其中1例在术后1.5mo出现免疫排斥,角膜溶解引起穿孔,加大全身性免疫抑制剂量来控制病情。3例眼中植片无法在角膜表面重新形成上皮,被定为原发性失败。其余4眼有部分上皮形成,但上皮细胞无法完全覆盖角膜表面。术前最佳矫正视力从手动到1m处数指,术后最佳矫正视力从光感到20/80。有5眼视力得到改进,不需其他治疗。手术失败的主要原因为干眼症和持续性炎症。结论:对于能控制泪量和眼部炎症的病例,亲属活体异体角膜缘和羊膜移植是治疗化学性眼外伤造成的角膜缘干细胞缺失最佳方法之一。  相似文献   
107.
Objective measurements derived from digitized laryngeal stroboscopic images were used to demonstrate changes in vocal fold vibration and in the size of benign lesions after 3 months of voice therapy. Forty chronically dysphonic patients were studied. By means of a rigid stroboscope, pretreatment and posttreatment recordings were made of the vocal folds at rest and under stroboscopic light during phonation. From each recording, images of the positions at rest and during vibration at maximal opening and at maximal closure were digitized. The surface areas of any lesions and of the glottal gap were independently measured in the digitized images by 2 experienced laryngologists. Referential distances were determined in order to compensate for discrepancies in magnification in the various recordings. After 3 months of voice therapy, significant improvement in lesion size and degree of maximal closure during vibration could be demonstrated in about 50% of the patients. The degree of maximal opening did not prove to be a significant parameter.  相似文献   
108.
Analyzing data from ordered categories   总被引:12,自引:0,他引:12  
Clinical investigations often involve data in the form of ordered categories--e.g., "worse," "unchanged," "improved," "much improved." Comparison of two groups when the data are of this kind should not be done by the chi-square test, which wastes information and is insensitive in this context. The Wilcoxon-Mann-Whitney test provides a proper analysis. Alternatively, scores may be assigned to the categories in order, and the t-test applied. We demonstrate both approaches here. Sometimes data in ordered categories are reduced to a two-by-two table by the collapsing of the high categories into one category and the low categories into another. This practice is inefficient; moreover, it entails avoidable subjectivity in the choice of the cutting point that defines the two super-categories. The Wilcoxon-Mann-Whitney procedure (or the t-test with use of ordered scores) is preferable. A survey of research articles in Volume 306 of the New England Journal of Medicine shows many instances of ordered-category data (about 20 per cent of the articles had such data) and no instance of analysis by the preferred methods presented here. We suggest that investigators who are unfamiliar with these methods should seek the assistance of a professional statistician when they must deal with such data.  相似文献   
109.
PURPOSE: Owing to the use of immunosuppressive drugs, renal transplant recipients are at risk for malignancies including Kaposi's sarcoma (KS). Following the diagnosis, physicians tend to decrease the doses of immunosuppressive drugs to lower tumor progression rate. On the other hand, those who receive lower doses of immunosuppressive drugs are at a higher risk for acute rejection. In this study, we evaluated the outcome of KS on renal allografts following discontinuation or decrease in the doses of drugs. METHODS: Since 1984, 14 (nine men and five women) among 2000 cases of renal transplantation have been diagnosed as KS. In 11 patients, cyclosporine was completely discontinued, the dosage was decreased to half of the initial dose in other cases. Except one case, we discontinued either azathioprine or mycophenolate mofetil. RESULTS: During 57 months of follow-up on average, the serum creatinine level remained normal in 10 but increased in four cases. Kidney function deteriorated in two of these four patients at the beginning of study. Three patients died with normal serum creatinine levels. Discontinuation of immunosuppressive drugs caused complete remission of KS in all patients except one who received chemotherapy. CONCLUSION: Discontinuation of immunosuppressants following the diagnosis of KS caused complete remission of this cancer in almost all patients and seemed to be relatively safe for kidney graft function.  相似文献   
110.
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