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991.
The volatile anesthetic agents halothane, enflurane, and isoflurane are chlorofluorocarbons (CFC) and contribute to ozone depletion. Although the contribution is small, its importance is rising, as technical CFCs will be phased out according to the Montreal protocol (1987) and the London conference (1990) by the year 2000. Alternative procedures and CFC-free volatile agents such as des- and sevoflurane do not contribute to depletion of the ozone layer, but will not replace standard methods using volatile anesthetic agents in the near future. METHODS. In an experimental setup, we filtered anesthetic waste gases from scavenging systems of rebreathing circles by activated carbon filters. The filtered substances were desorbed by a heat chamber and condensed in a cold trap. RESULTS. By this method, it was possible to retrieve 50%-60% of the applied gases. Gas chromatographic analysis showed halothane containing traces of pollutants and isoflurane and enflurane as pure substances. DISCUSSION. The retrieval of anesthetic waste gases is easy; no sophisticated technical equipment is necessary. Purity of substances could make recycling possible and offer a method to avoid environmental pollution by volatile anesthetics.  相似文献   
992.
993.
Almost 90% of primary acute pericarditis are idiopathic. Between specifics forms, a very low percentage of cases are due to chronic rheumatic diseases. A case of adult Still's disease (juvenile chronic rheumatoid arthritis) with acute pericarditis being the first clinical manifestation (besides fever and general syndrome) is presented. Therapy with oral prednisone was rapidly effective, and pericardial effusion resolved after 3 weeks of treatment, as echocardiography showed.  相似文献   
994.
Inherited defects of the natural coagulation inhibitors predispose patients to thrombosis. These disorders have similar clinical presentations with a strong family history of thrombosis, episodes of recurrent venous thromboembolism, beginning in early adulthood. We report a case of upper gastrointestinal bleeding in a patient with portal hypertension due to portal-vein thrombosis secondary to hereditary protein C deficiency, an association that has seldom been reported.  相似文献   
995.
We demonstrate the effect of deep brain stimulation of the ventral intermediate thalamic nucleus on intractable action tremor, in a 72-year-old man suffering from neuropathy associated with monoclonal gammopathy.  相似文献   
996.
997.
We present 5 patients with cyanotic congenital heart disease in whom a pulmonary valvuloplasty was performed as palliative therapy. The patients symptoms were hypoxemic spells, very low oxygen saturation and no weight gain. The oxygenation improved and symptoms disappeared. We believe that in properly selected patients this technique represents a good therapeutic modality.  相似文献   
998.
In a long-term study nine ileo-rectally anastomosed (IRA) and seven post-valve T-caecum (PVTC)-cannulated pigs were compared with six intact pigs with regard to different blood variables, sodium and potassium retention and weights of selected organs. After surgery, apart from urea and K measured 13 weeks post-surgery, there were no differences in the blood variables between the PVTC-pigs and intact pigs. In IRA-pigs concentrations of creatinine (P < 0.01), Na (P < 0.001), base excess (P < 0.001), pH (P < 0.01) and bicarbonate (P < 0.001) in blood were lower than those in intact pigs. At 13 weeks after surgery the blood K concentration in IRA-pigs was higher (P < 0.001) than that in PVTC-pigs or intact pigs. At 6 weeks after surgery the blood urea concentration in IRA-pigs was higher (P < 0.001) than that in intact and PVTC-pigs. At 13 weeks after surgery the urea concentration in PVTC-pigs was higher (P < 0.001) than those in IRA-pigs or intact pigs. The Na (P < 0.01 11 weeks after surgery) and (P < 0.05 and P < 0.01 5 and 11 weeks after surgery respectively) balances in IRA-pigs were lower than those in intact animals. Na retention was negative for IRA-animals 11 weeks after surgery. Na and K retentions were similar in PVTC-pigs and in intact pigs. The urinary: faecal excretion of Na differed slightly between PVTC-animals and intact animals. At 13 weeks after surgery there were no differences in organ weights between the PVTC-pigs and intact animals. In the IRA-pigs the weights of the liver (P > 0.05), the kidneys (P > 0.05) and the adrenal glands were higher (P < 0.001) than those in the intact animals.  相似文献   
999.
1000.
OBJECTIVE: To test whether healthcare workers' knowledge of and compliance with the basic principle of the Universal Precautions policy (i.e., that all patients should be treated equally regarding contact with body fluids) influenced the rate of contact with patient blood. DESIGN: Survey based on anonymous questionnaires. SETTING: A 380-bed secondary and tertiary care hospital receiving emergency and elective patients. PARTICIPANTS: All employees having any contact with patients. Nine hundred one of 1,308 (69%) of the questionnaires were returned. RESULTS: Twelve percent of the respondents (95% confidence interval [CI95] = 10.0%-14.4%) had experienced any contact with patient blood in the week preceding their answer. Physicians had the highest rate of contact with blood followed by nurses. In the five groups--physicians, nurses, laboratory technicians and phlebotomists, nursing aides, and student nurses--contact with blood was less frequent in the subgroup that did know and comply with the basic principle of the Universal Precautions policy, compared with the subgroup that did not. When adding the results for the 5 groups, contact with blood was experienced by 91 of 571 (15.9%, CI95 = 13%-19%) of the personnel who did not know and comply with Universal Precautions. The personnel who did know and comply with Universal Precautions had a significantly lower (9 of 111 [8.1%], p < .05, CI95 = 3.8%-15%) rate of contact with blood. CONCLUSIONS: The healthcare workers who knew and complied with Universal Precautions had a significant lower rate of contact with patient blood than those who did not.  相似文献   
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