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71.
Potential challenges facing distributed leadership in health care: evidence from the UK National Health Service 下载免费PDF全文
Graeme Martin Nic Beech Robert MacIntosh Stacey Bushfield 《Sociology of health & illness》2015,37(1):14-29
The discourse of leaderism in health care has been a subject of much academic and practical debate. Recently, distributed leadership (DL) has been adopted as a key strand of policy in the UK National Health Service (NHS). However, there is some confusion over the meaning of DL and uncertainty over its application to clinical and non‐clinical staff. This article examines the potential for DL in the NHS by drawing on qualitative data from three co‐located health‐care organisations that embraced DL as part of their organisational strategy. Recent theorising positions DL as a hybrid model combining focused and dispersed leadership; however, our data raise important challenges for policymakers and senior managers who are implementing such a leadership policy. We show that there are three distinct forms of disconnect and that these pose a significant problem for DL. However, we argue that instead of these disconnects posing a significant problem for the discourse of leaderism, they enable a fantasy of leadership that draws on and supports the discourse. 相似文献
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73.
Maldonado-Martín A Rueda-Illescas D Gil-Extremera B Soriano-Carrascosa L Alonso-Morales T García-Pérez F García-Chicano J de Dios Luna del Castillo J 《Journal of clinical hypertension (Greenwich, Conn.)》2002,4(5):346-9, 354
Endothelin has been identified as a potent vasoconstrictor. The aim of this study was to evaluate urinary endothelins and their relation to other markers of renal damage, such as microalbuminuria, creatinine, and N-acetyl-beta-glucosaminidase (NAG), in a group of recently diagnosed (less than 1 year) hypertensive subjects and a control group. We selected 50 subjects and divided them into two groups: 27 hypertensive patients (15 females and 12 males) without previous pharmacologic therapy, and 23 healthy, normotensive subjects (12 females and 11 males). All patients underwent a history and physical examination, chest x-ray, electrocardiography, funduscopy, and hematologic and biochemical analyses. Endothelins, microalbuminuria, creatinine, and NAG values were also determined in 24-hour urine samples. Creatinine, microalbuminuria, and NAG values were found to be higher in hypertensive than in normotensive subjects. The hypertensive group showed a nonsignificant elevation of total endothelin. In conclusion, the determination of elevated urinary endothelin does not appear to be an early marker of organ damage in hypertensive subjects. The urinary excretion of protein, creatinine, and NAG was higher in hypertensive subjects. A positive correlation was found between the urinary excretion of endothelins and markers of renal damage, microalbuminuria and NAG values. The relationship between endothelins and hypertension was without statistical significance. 相似文献
74.
Protective role of melatonin and retinol palmitate in oxidative stress and hyperlipidemic nephropathy induced by adriamycin in rats 总被引:2,自引:0,他引:2
Pedro Lopez Montilla Isaac Fiñana Túnez Carmen Muñoz de Agueda Felix Luna Gascón Juan Vicente López Soria 《Journal of pineal research》1998,25(2):86-93
Abstract: We have studied the effects of melatonin and retinol palmitate (RP) on the nephropathy and oxidative stress induced by a single and high dose of adriamycin (AD) in Wistar male rats. A dose of melatonin (75 μg/ kg/day) and a dose of RP (0.25 g oily solution/kg/day, sc) were injected 3 and 9 days before and after the administration of AD (25 mg/kg, i.p.), respectively. After the decapitation, samples were taken from the neck vascular trunk in order to determine the triglycerides, total cholesterol, phospholipids, HDL-cholesterol, total proteins, urea, lipoperoxides, and reduced glutathione (GSH). We estimated the lipoperoxide and glutathione (GSH) contents in renal homogenates, and the excretion of proteins in urine over a 24 hr period. The administration of AD caused significant increases in proteinuria and in the other parameters studied [lipids (triglycerides, total cholesterol, phospholipids, and HDL-cholesterol), nonprotein nitrogen compounds, and lipoperoxides]. AD increased the lipoperoxide content, but it decreased the GSH content in the kidney. Both melatonin and RP, although melatonin more significantly, decreased the intensity of the changes produced by the administration of AD alone. In fact, melatonin was quite efficient in reducing the formation of lipoperoxides, restoring renal GSH content and decreasing remarkably the severity of proteinuria. These results support the powerful antioxidant action of melatonin at renal level and a lower antioxidant action of retinol. Likewise, these data reinforce the hypothesis which supports the pathogenetic role and the close relation between the oxidative stress and the expression of the nephropathy induced by AD. However, in spite of this obvious antioxidant effect of melatonin in the kidney, additional studies are required to establish accurately the role of this pineal indole in the regulation and dynamics of the antioxidative defense enzyme system, which neutralizes the damaging effect of free radicals, both endogenous and exogenous, in this organ. 相似文献
75.
Yehuda Adler Yaron Finkelstein Abid Assali Josep Guindo Antoni Bayes-Genis Antony Bayes De Luna Asaad Khouri 《Clinical cardiology》1998,21(2):143-144
On the basis of our reported experience with colchicine for recurrent pericarditis, we administered colchicine to two patients with large pericardial effusions complicating idiopathic pericarditis. The first was a 26-year-old male who showed clinical deterioration following emergency pericardiocentesis and aspirin (3 g/day) for 10 days; the second was a 2-year-old girl who was unsuccessfully treated with aspirin (100 mg/kg/day) for 2 weeks, followed by corti-costeroids for 7 months. Administration of colchicine (1 mg/ day) instead of aspirin in the first case, and with a rapid tapering-off of the corticosteroids in the second case, led to complete regression of the pericardial effusion on echocardiography within 1 week and 1 month, respectively. Colchicine was discontinued after 1 month in the first patient and was continued for 6 months in the child. Neither has had a recurrence at 24 and 6 months of follow-up, respectively. No side effects of colchicine were observed. We conclude that colchicine may be effective in the treatment of large pericardial effusion when therapy with nonsteroidal anti-inflammatory drugs and/or corticosteroids fails. 相似文献
76.
Robert G. Tieleman MD PhD Isabelle C. Van Gelder MD Hans A. Bosker MD Tsjerk Kingma MSc Arthur A.M. Wilde MD Charles J.H.J. Kirchhof MD Johan H. Bennekers MD Frank A.L.E. Bracke MD Nic J.G.M. Veeger MSc Jaap Haaksma PhD Maurits A. Allessie MD PhD Harry J.G.M. Crijns MD 《Heart rhythm》2005,2(3):1-230
OBJECTIVES: The purpose of this study was to evaluate the hypothesis that presumed reversion of electrical remodeling after cardioversion of atrial fibrillation (AF) restores the efficacy of flecainide. BACKGROUND: Flecainide loses its efficacy to cardiovert when AF has been present for more than 24 hours. Most probably, the loss is caused by atrial electrical remodeling. Studies suggest electrical remodeling is completely reversible within 4 days after restoration of sinus rhythm (SR). METHODS: One hundred eighty-one patients with persistent AF (median duration 3 months) were included in this prospective study. After failure of pharmacologic cardioversion by flecainide 2 mg/kg IV (maximum 150 mg in 10 minutes) and subsequent successful electrical cardioversion, we performed intense transtelephonic rhythm monitoring three times daily for 1 month. In case of AF recurrence, a second cardioversion by flecainide was attempted as soon as possible. RESULTS: AF recurred in 123 patients (68%). Successful cardioversion by flecainide occurred only when SR had been maintained for more than 4 days (7/51 patients [14%]). Failure to cardiovert was associated with a prolonged duration of the recurrent AF episode and concurrent digoxin use. Multivariate logistic regression confirmed that successful cardioversion was determined by digoxin use (odds ratio [OR] 0.093, P = .047) and by the interaction between the duration of SR and the (inverse) duration of recurrent AF (OR 6.499, P < .001). When flecainide was administered within 10 hours after AF onset and the duration of SR was greater than 4 days, the success rate was 58%. CONCLUSIONS: Flecainide recovers its antiarrhythmic action after cardioversion of AF. However, successful pharmacologic cardioversion occurs only after SR has lasted at least 4 days and is expected only for recurrences having duration of a few hours. Immediate pharmacologic cardioversion of AF recurrence may be a worthwhile strategy for management of persistent AF. 相似文献
77.
Identification of the receptor for erythropoietin by cross-linking to Friend virus-infected erythroid cells. 总被引:9,自引:1,他引:9 下载免费PDF全文
S T Sawyer S B Krantz J Luna 《Proceedings of the National Academy of Sciences of the United States of America》1987,84(11):3690-3694
Erythropoietin (Epo) is a glycoprotein hormone that regulates erythroid development and interacts with surface receptors on developing erythroid cells. In this laboratory, a cell system with a relatively pure population of erythroid cells that respond to Epo has been developed. Immature erythroid cells are obtained from the spleens of mice infected with the anemia strain of Friend virus. The binding of 125I-labeled Epo (125I-Epo) to plasma membranes from these cells was studied in this investigation. 125I-Epo binding reached equilibrium within 20 min at 37 degrees C. Twenty percent of the receptors bound 125I-Epo with a Kd of 0.08 X 10(-9) M, while the remaining receptors bound the hormone with a Kd of 0.6 X 10(-9) M. In this study, a receptor for Epo was identified by cross-linking 125I-Epo to the receptor in intact cells and plasma membrane preparations using disuccinimidyl suberate. Polyacrylamide gel electrophoresis revealed two labeled bands of 100 and 85 kDa. The 85-kDa band was more heavily labeled (65%) than the 100-kDa band. Both bands were equally decreased when increasing amounts of unlabeled Epo were included in the binding mixture, indicating a specific interaction of 125I-Epo with the receptor. 相似文献
78.
Chinnakotla AK De Luna AM Thew ST Anderson BR Cantave IM 《The American journal of gastroenterology》2001,96(7):2248-2250
We report a rare case of symptomatic GI amyloidosis in an HIV-infected patient who ultimately developed uncontrollable upper GI bleeding. Gastric and jejunal biopsies revealed amyloidosis. Although the patient's history suggested the possibility of secondary amyloidosis, immunohistochemical staining together with serum electrophoresis and immunofixation revealed the presence of lambda light chains indicating primary amyloidosis. 相似文献
79.
Molecular characterization of the t(2;5) (p23; q35) translocation in anaplastic large cell lymphoma (Ki-1) and Hodgkin's disease 总被引:1,自引:3,他引:1
80.
In this paper, the approach to the genesis of the acute hypertension of pregnancy, uses a conceptual and methodological perspective adjusted to its multifactorial nature; a set of questions with epidemiologic focus is proposed, in order to vinculate psychosocial factors with the biologic processes characteristic of this health problem. 相似文献