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81.
This article summarizes research findings on the roles of management approach and vision, delivery system design, human assets, advanced technology, and performance assessment in generating world class health care organizations.  相似文献   
82.
Extracorporeal shock wave lithotripsy and percutaneous nephrostolithotomy have become widely used technologies for removal of urinary calculi, despite a lack of adequate evaluative studies. The possibility of long-term adverse effects of these treatments has been raised, particularly an increase in stone recurrence and development of hypertension following extracorporeal shock wave lithotripsy. We conducted a retrospective study of 1,000 patients treated with extracorporeal shock wave lithotripsy or percutaneous nephrostolithotomy for upper tract stone disease to assess immediate effectiveness and complications, with prospective follow-up to assess stone recurrence and development of hypertension. The effectiveness of each treatment (defined in terms of patients rendered stone-free or having only fragments at discharge) was similar for most stone types. While stone recurrence rates in the first 2 years after treatment were similar in the two groups, cumulative recurrence at 3 years was higher following extracorporeal shock wave lithotripsy compared to percutaneous nephrostolithotomy (39% vs. 23%, p = 0.04). However, logistic regression and Kaplan-Meier analyses showed no significant difference in clinically evident recurrence for patients treated with extracorporeal shock wave lithotripsy. Cumulative incidence of clinically evident stone recurrence did not differ significantly between patients with fragments at discharge (20%) and patients rendered stone-free (15%) (p = 0.24). There was no difference in the development of new hypertension requiring medical treatment. Our findings indicate that extracorporeal shock wave lithotripsy is effective and associated with lower short-term morbidity than percutaneous nephrostolithotomy. Stone fragments left behind by lithotripsy do not appear to confer significant risk of early stone recurrence. Further study is necessary to define long-term risk of recurrence following extracorporeal shock wave lithotripsy.  相似文献   
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Roth LG 《Hospital topics》1990,68(3):19-22
Among the healthcare regulations enacted by New York State Health Commissioner Dr. David Axelrod is one requiring a comprehensive compulsory survey of each New York hospital by the state health department. A medical director offers his thoughts on the survey and describes its impact on his hospital.  相似文献   
85.
Acute effects of using a mobile phone on CNS functions   总被引:9,自引:0,他引:9  
Twenty volunteers participated in two experiments exploring the acute effects of using the mobile phone Motorola GSM 8700 on the functions of the CNS. When speaking (5 minutes reading a text from daily newspapers) the electromagnetic fields from the mobile apparatus did not affect the visual evoked potentials. Also a 6-min exposure did not reveal any effect of electromagnetic fields on the results in two tests (memory and attention) performed while speaking into the mobile. On the other hand the phone call itself strongly influenced the performance in a secondary task applying a test of switching attention which is a good model for driving a car. The response and decision speed were significantly worse. This is a proof that even a slight psychological stress involved in calling while driving can be a great risk.  相似文献   
86.
If current is flowing in cardiac tissue, and if the myocardial fibres approach a sealed boundary at an angle, then the tissue within a few length constants of the boundary is polarised. This polarisation occurs when the cardiac tissue has different anisotropy ratios in the intracellular and extracellular spaces. This new mechanism of tissue polarisation is demonstrated using a simple, analytical model, and it is shown quantitatively that this polarisation can be nearly as large as that occurring near an electrode.  相似文献   
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89.
The diagnostic value of MRI in acute and chronic posttraumatic wrist pain will be demonstrated in several clinical cases. The integration of MRI in a diagnostic algorithm is discussed. The indication of MRI is given for suspected complex ligamentous lesions, occult fractures and soft tissue pathologies, in particular with disconcordant clinical and radiological signs. Pathology orientated study protocols are presented. Preoperatively, MRI will be helpful in planning definitive surgical treatment.  相似文献   
90.
This study investigated the effect of a multivitamin preparation administered before ischemia or before reperfusion, on ischemia-reperfusion (I/R) injury of skeletal muscle. An in vivo hindlimb skeletal muscle I/R model (2.5 h/2 h) was carried out on adult New Zealand white rabbits. Animals used as I/R models were treated with a multivitamin preparation (0.4 ml/kg bw i.v. bolus), containing alpha-tocopherol, ascorbic acid, retinol, vitamin B complex, 30 min before starting ischemia (group MV(isc)) or 5 min before reperfusion (group MV(rep)) and compared to animals with I/R without treatment (group IR) and sham operated animals (group SHAM). Interstitial edema (muscle interfiber area, %MIFA) and changes in microvessel size (microvessel cross sectional area, MVCSA, microm(2)) were measured. Plasma malondialdehyde concentrations (MDA-TBA, nmol/ml) served as a measure of lipid peroxidation. After 2h of reperfusion, ischemia-reperfusion developed a significant microvascular constriction and an interstitial edema (IR, vs SHAM;P< 0.01), but administration of antioxidative vitamins before the onset of ischemia reduced microvascular constriction and edema formation (P< 0.05 vs IR group). In a similar manner, administration of vitamins before ischemia lowered plasma MDA-TBA levels as compared to the untreated group during reperfusion (p< 0. 05). In animals treated with vitamins before reperfusion, the biochemical and morphological results showed no differences as compared to the untreated group.Antioxidative treatment with a multivitamin preparation exerted a beneficial effect on I/R injury of skeletal muscle when the aforementioned vitamins were administered before ischemia but not before the onset of reperfusion.  相似文献   
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