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The Joint Commission on Accreditation of Healthcare Organizations' (JCAHO) Agenda for Change has refocused and redefined quality monitoring in health care. The JCAHO has operationalized these new concepts of quality monitoring and evaluation by means of a 10-step process that includes the development of clinical indicators. Theoretical frameworks for the 10-step process were drawn from the work of theorists whose applications of quality-monitoring methods occurred in business and industry. An enhanced understanding of the current JCAHO definitions of quality and processes for quality measurement will help practitioners prepare for future accreditation surveys. A review of quality monitoring and evaluation activities in nutrition support has demonstrated a need for more published accounts to document these important activities.  相似文献   
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聚乙二醇(PEG)上的活性基团结合在红细胞表面掩盖血型抗原是制备通用血型红细胞的途径之一,这些PEG链有很强的水合作用,能覆盖红细胞表面的大片区域,阻断血型抗原与抗体结合。甲基氧PEG-5000(mPEG-5000)是常用的红细胞修饰剂,主要修饰蛋白上的氨基基团。在氯化氰脲酸(CnCl)催化下,mPEG-5000与红细胞膜上氨基形成共价键连接,掩盖Rh抗原和A或B抗原。CnCl-PEG-5000浓度越高,血型抗原的覆盖效果越好。由于微环境下A和B血型抗原处无氨基基团或者氨基基团不能被CnCl-PEG-5000修饰,不能完全阻断抗-A、B与A和B血型抗原结合。本文报道…  相似文献   
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Amino acid alterations and encephalopathy in the sepsis syndrome   总被引:2,自引:0,他引:2  
OBJECTIVE: To evaluate the role of amino acid profiles in septic encephalopathy. DESIGN: Retrospective analysis. SETTING: Medical wards and medical ICU of a university hospital. PATIENTS: Patients with infections and normal mental status were compared with patients with septic shock and altered sensorium. INTERVENTIONS: Plasma amino acid levels and Acute Physiology and Chronic Health Evaluation (APACHE II) scores were determined. MEASUREMENTS AND MAIN RESULTS: Patients with septic shock and altered sensorium had higher circulating concentrations of ammonia (425 +/- 55 vs. 127 +/- 7 mmol/L) and the aromatic amino acids phenylalanine (122 +/- 19 vs. 74 +/- 3 mmol/L) and tryptophan (97 +/- 7 vs. 32 +/- 13 mmol/L), and lower levels of the branch-chain amino acid isoleucine (48 +/- 7 vs. 68 +/- 5 mmol/L) than patients with infections and normal sensorium (p less than .05). Aromatic amino acid levels correlated with APACHE II scores (R2 = .4, p less than .001) and mortality. APACHE II scores were higher in the septic shock patients (30 +/- 2 vs. 8 +/- 1, p less than .001), and these patients had a higher mortality rate (71% vs. 12%, p less than .01). Patients with septic shock who died had higher levels of ammonia (524 +/- 58 vs. 227 +/- 40 mmol/L, p less than .05) and sulfur-containing amino acids (172 +/- 31 vs. 61 +/- 7 mmol/L, p less than .05) than patients who survived. CONCLUSIONS: Plasma amino acid profiles appear to be important in septic encephalopathy and the severity of septic disease.  相似文献   
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Leptin enhances agonist-induced platelet aggregation, and human platelets have been reported to express the leptin receptor. However, the pathways and mediators lying downstream of leptin binding to platelets remain, with few exceptions, unknown. In the present study, we sought to gain further insight into the possible role of leptin as a platelet agonist. Stimulation of platelets with leptin promoted thromboxane generation and activation of alpha(IIb)beta(3), as demonstrated by PAC-1 binding. Furthermore, it increased the adhesion to immobilised fibrinogen (p<0.001) and induced cytoskeletal rearrangement of both platelets and Meg01 cells. Leptin time- and dose-dependently phosphorylated the intracellular signalling molecules JAK2 and STAT3, although the importance of STAT3 for leptin-induced platelet activation remains to be determined. Important intracellular mediators and pathways activated by leptin downstream of JAK2 were found to include phosphatidylinositol-3 kinase, phospholipase Cgamma2 and protein kinase C, as well as the p38 MAP kinase-phospholipase A(2) axis. Accordingly, incubation with the specific inhibitors AG490, Ly294002, U73122, and SB203580 prevented leptin-mediated platelet activation. These results help delineate biologically relevant leptin signalling pathways in platelets and may improve our understanding of the mechanisms linking hyperleptinaemia to the increased thrombosis risk in human obesity.  相似文献   
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The indications for thrombolytic treatment in normotensive patients with pulmonary embolism (PE) are still the subject of debate, and it also remains questionable whether the efficacy and safety of thrombolysis are similar in men and women. To address the latter issue, the present study analyzed a large population of 428 women and 291 men with acute submassive PE derived from a prospective multicenter registry. Initial treatment consisted either of thrombolysis (<24 hours after diagnosis) or heparin alone. Thirty-day overall mortality was almost identical (11%) in heparin-treated men and women. Early thrombolysis was associated with drastically reduced death rates (2.7% vs 11% in the heparin group, p = 0.033) in men, whereas the reduction was nonsignificant (p = 0.181) in women. Multivariate analysis revealed that early thrombolysis was independently associated with reduced mortality rates in men (odds ratio 0.21, 95% confidence interval 0.05 to 0.96). In comparison, its favorable effect in women was marginal (odds ratio 0.77, 95% confidence interval 0.30 to 1.97). Gender-specific differences were also observed with regard to the reduction of symptomatic PE recurrence (in men, from 21.6% to 8.2%, p = 0.009; in women, from 16.9% to 8.3%, p = 0.049). In contrast, thrombolysis resulted in a more than threefold increase in major bleeding in women (from 8.4% to 27.1%, p <0.001), a more pronounced effect than in men (from 6.9% to 15.1%, p = 0.055). In conclusion, the present study generated the hypothesis that women with submassive PE might benefit less from thrombolytic treatment in terms of survival and PE recurrence and that they could be exposed to a higher bleeding risk compared with men.  相似文献   
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Background In acne vulgaris patients, the presence of a dysregulation of the production of innate and specific antimicrobial peptides has been postulated. Objective This study aims to determine whether human neutrophil proteins (HNP) 1–3 are expressed in acne patients. Materials and methods HNP 1–3 expression was investigated in 35 acne patients treated with isotretinoin and in 25 healthy subjects. At the beginning of the study, two skin biopsies were taken from acne patients; one biopsy was taken from an established pustule and one from uninvolved skin, and the biopsies were repeated after treatment. Only one biopsy was obtained from controls. Results The statistical analysis showed that pustular lesions of acne patients had significantly higher levels of perivascular and interstitial HNP 1–3 expression when compared with the biopsy of uninvolved skin of these patients (P = 0.003, P = 0.001, respectively) and with that of healthy controls (P = 0.007, P = 0.014, respectively). Isotretinoin treatment achieved a decrease in the perivascular and interstitial HNP 1–3 expression of pustular lesions (P = 0.01, P = 0.001, respectively). Conclusion Our current study demonstrates the novel observation that a recently identified antimicrobial peptide, HNP 1–3, is expressed in neutrophils of acne inflammation but not in uninvolved skin of these patients. These results suggest that HNP 1–3 may contribute to the development of inflammatory lesions of acne.  相似文献   
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The application of optical projection tomography to in-vivo experiments is limited by specimen movement during the acquisition. We present a set of mathematical correction methods applied to the acquired data stacks to correct for movement in both directions of the image plane. These methods have been applied to correct experimental data taken from in-vivo optical projection tomography experiments in Caenorhabditis elegans. Successful reconstructions for both fluorescence and white light (absorption) measurements are shown. Since no difference between movement of the animal and movement of the rotation axis is made, this approach at the same time removes artifacts due to mechanical drifts and errors in the assumed center of rotation.  相似文献   
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