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41.
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   
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The aetiology of porphyria cutanea tarda (PCT) has not been elucidated, but the possibility of an autoimmune mechanism has been proposed. We report a case of an unknown clinical combination of PCT with autoimmune hypothyroidism, alopecia universalis and vitiligo with thyroid and parietal cell circulating antibodies. This is highly suggestive of underlying autoimmune damage in this patient.  相似文献   
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A fibre optic potassium ion sensor has been developed based on reflectance measurements of the pH-dependent chromogenic crown ether 'Takagi reagent' immobilized on the non-ionic polymeric resin Amberlite XAD2. The sensor response is in the 1.5-100 mM range with a detection limit of 0.25 mM K+. The selectivity factor over sodium is 20. The proposed sensor works with a reproducibility of +/- 0.8% at the 5 mM K+ level. Advantageous design features include ease of construction, simplicity of use, reversibility, short response time (approximately 1 min) and an optimum working pH range (7.0-8.0) for biological fluids. This optical sensor was applied successfully to the direct determination of potassium in human serum. Aqueous potassium standards containing 0.13 M NaCl and a buffer of pH 8 were used for calibration.  相似文献   
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Back pain among nurses is a common problem. Prior studies of this problem have been based on cross-sectional or retrospective data. This 18-month prospective study involving nurses newly graduated from nursing school investigated personal, worksite, and training factors associated with future risk of back pain. Each nurse underwent a preliminary interview and periodic follow-ups to identify those with back injuries. Contingency tables and logistic regression analyses demonstrated that prior significant back pain episodes (evidenced by previous job changes because of back pain, frequent medication use, etc.) were associated with increased future risk. Training at nursing school or on the job did not have a protective effect. This pilot study therefore suggests factors useful in placement and counseling of new nurses and indicates the need for further implementation of mechanical lift assist device use. © 1994 Wiley-Liss, Inc.  相似文献   
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INTRODUCTION: In patients (pts) with atrial fibrillation (AF) of more than 48 hours' duration, electrical cardioversion (ECV) should only be performed after 3 weeks of effective anticoagulation. Transesophageal echocardiography (TEE) allows earlier ECV; however, despite exclusion of thrombi in the atrium and left atrial appendage (LAA), cases of thromboembolism related to ECV have been documented in AF. To define a low-risk group for cardioversion without previous anticoagulation, pts were selected for immediate ECV if no thrombi or dynamic spontaneous echo contrast (auto-contrast) were found after TEE and if LAA velocity was more than 0.25 m/sec. METHODS AND RESULTS: We performed TEE in 31 consecutive pts referred for ECV for AF of more than 48 hours' duration and without previous anticoagulation. After TEE the pts eligible for immediate ECV began anticoagulation with low molecular weight heparin (enoxaparin), subcutaneously in therapeutic doses, together with warfarin immediately before cardioversion. Enoxaparin was continued until an INR of over 2 was reached. Based on the TEE findings, the pts were divided in 2 groups: immediate ECV, group A, 20 pts with a mean age of 62 +/- 13 years, 6 female; and conventional therapy with warfarin before ECV, group B, 11 pts, mean age of 67 +/- 10 years (p < 0.05), 2 female. None of the pts in either group had mitral stenosis or previous episodes of thromboembolism. The mean transverse diameter of the left atrium in the 31 pts was 47 +/- 4.5 mm, without statistically significant differences between the 2 groups. Of the 11 pts in group B, 3 had a thrombus in the LAA, 6 dynamic spontaneous echo contrast and the remainder LAA velocities of less than 0.25 m/sec. ECV was achieved in all the pts, with no complications. Oral anticoagulation was maintained for at least a month. At one month, sinus rhythm was maintained in 75% of group A and 45% of group B (p < 0.01). CONCLUSION: In pts with AF of more than 48 hours' duration and no previous history of thromboembolism, the use of our exclusion criteria during TEE enabled stratification of a low-risk population for immediate ECV, which was accomplished effectively and safely in 2/3 of the pts. This strategy is associated with early symptomatic improvement, and may contribute to maintenance of sinus rhythm after one month, which was significantly better than in the pts who had prolonged therapy with warfarin before ECV, despite the differences found in age and left ventricular function.  相似文献   
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Pulmonary embolism (PE) is an important health problem and often a major clinical challenge, not only because of the low specificity of its clinical manifestations but also because of the increasing number of medical circumstances that are risk factors for this illness and the importance of early identification, since prompt and appropriate treatment can decrease mortality from this disease by about 25%. In recent years research on PE has been extensive, directed mainly at trying to determine and characterize its risk factors, establish new clinical probability algorithms, develop new diagnostic methods and put existing ones into perspective, seek new therapeutic approaches (pharmacological and non-pharmacological), and above all establish protocols that can guide the clinician from the stage of clinical suspicion to measures to prevent recurrence. It was the authors' aim to review the most significant literature on this subject, in order to produce a text that reflects the state of the art concerning PE and that can be used as a guide in the clinical approach to this pathology.  相似文献   
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