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81.
82.
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   
83.
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   
84.
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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87.
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   
88.
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   
89.
Interventions for parvovirus B19 infection need to balance the low risk of infection at a population level with the potential for serious adverse outcome for particular groups, notably the fetus, people with haemoglobinopathies and the immunocompromised. This guidance aims to assist the local decision-making process to be as evidence-based as the available evidence allows.  相似文献   
90.
Metabolism and excretion of atorvastatin in rats and dogs.   总被引:1,自引:0,他引:1  
Atorvastatin (AT) is a second-generation potent inhibitor of 3-hydroxy-3-methylglutaryl-CoA reductase, clinically approved for lowering plasma cholesterol. Using a mixture of [D(5)/D(0)] AT and/or [(14)C]AT, the metabolic fate and excretion of AT were examined in rats and dogs following single and multiple oral doses. Limited biliary recycling was examined in one dog after a single dose of AT. AT-derived metabolites in bile samples were identified by metabolite screening of the [D(5)/D(0)] AT molecular clusters using tandem mass spectrometry. Bile was a major route of [(14)C] drug-derived excretion, accounting for 73 and 33% of the oral dose in the rat and dog, respectively. The remaining radioactivity was recovered in the feces; only trace amounts were excreted in urine. Radioactive components identified in rat and dog bile were the para- and ortho-hydroxy metabolites, a glucuronide conjugate of ortho-hydroxy AT, and unchanged AT. Two minor radioactive components were identified as beta-oxidation products of AT with one confirmed as a beta-oxidized AT derivative. The reappearance of AT and major metabolites in bile from a dog administered a sample of its previously excreted bile indicated biliary recycling is an important component in AT metabolism. Multiple dose administration in rats did not alter biliary metabolic profiles. Rat and dog plasma profiles after multiple dose administration were similar and showed no additional metabolites not found in bile. Examination of rat and dog bile and plasma indicates that AT primarily undergoes oxidative metabolism.  相似文献   
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