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81.
Torsade de pointes is a polymorphic form of ventricular tachycardia associated with prolongation of the QT interval, which may be either congenital or acquired. Etiologies for the acquired forms include drug effects, hypokalemia, hypomagnesemia, hypocalcemia, starvation, sick sinus syndrome, and atrioventricular block. We present a 76-year-old man with acute on chronic renal failure, hypocalcemia, on ciprofloxacin, and a prolonged QT interval with torsade de pointes triggered by hemodialysis. The QT prolongation was corrected by treating the hypocalcemia. Hypocalcemia and ciprofloxacin are known to independently cause prolonged QT interval and torsade de pointes; our case illustrates that dialysis can trigger torsade on a background of this risk factor combination.  相似文献   
82.
OBJECTIVE: To study the effect of reinforcement as a quality improvement intervention in the evidence-based management of the coronary syndromes. METHODS: In the pre-intervention phase, the charts of 140 consecutive patients with ICD-9 codes 410-414 for coronary syndromes were reviewed for measurement of total cholesterol on admission and fasting low density lipoprotein (LDL) cholesterol, implementation of aspirin therapy on admission, beta-blockers' use during hospitalization, and treatment with angiotensin converting enzyme (ACE) inhibitors in patients with left ventricular systolic dysfunction. Reinforcement was used as an intervention for quality improvement. All personnel of Division of Cardiology including nursing staff, medical residents, cardiology fellows, and attending physicians were reinforced to adhere to the evidence-based management. In the post-intervention phase, charts of 140 consecutive patients with ICD-9 codes 410-414 for coronary syndromes were reviewed to assess the improvement in the same quality of care parameters. RESULTS: By reinforcement, a significant improvement was noted in all quality of care parameters studied. Proportion of patients who had total cholesterol measured on admission increased from 78% to 92% (P<0.005), and those who had fasting LDL cholesterol measured increased from 22% to 70% (P<0.0001). Use of aspirin at admission (in 74% of patients pre- vs. 80% of patients post-intervention, P<0.05), beta-blockers during hospitalization (in 62% of patients pre- vs. 78% of patients post-intervention, P<0.001), and ACE inhibitors in patients with left ventricular systolic dysfunction (in 58% of patients pre- vs. 89% of patients post-intervention, P<0.001) improved significantly after reinforcement to the medical personal. CONCLUSION: Reinforcement to adhere to the evidence-based management results in a significant improvement in the quality of care provided to the patients with coronary syndromes.  相似文献   
83.
84.
AIM: To evaluate whether cortical scars can be detected using the summed images of technetium-99m-L,L-ethylenedicysteine (99mTc-L,L-EC) renal dynamic scan, and to compare the results with technetium-99m-dimercaptosuccinic acid (99mTc-DMSA) scan. To evaluate the inter-observer variability for 99mTc-L,L-EC and 99mTc-DMSA scan reporting. METHODS: One hundred and three patients were initially included in the study; 21 were excluded, five due to a single functioning kidney and 16 due to impaired renal function (serum creatinine>2.5 mg.dl(-1)). Eighty-two patients (39 females, 43 males), including 31 children, with a mean age of 33.4+/-11.3 years (range, 4 months to 74 years), underwent both 99mTc-DMSA and 99mTc-L,L-EC scintigraphy within a period of 14 days. 99mTc-L,L-EC images were regrouped into 2 min image sets, and the initial 2 min summed image (cortical phase) was used for the evaluation of scars. Three independent observers analysed both images separately on different days without being aware of the identity and clinical details of the patients. Their 99mTc-L,L-EC findings were compared with the consensus 99mTc-DMSA scan findings taken as reference. RESULTS: The overall sensitivity of 99mTc-L,L-EC scans was 93% and the specificity was 96%. The inter-observer variability was 0.91 for 99mTc-L,L-EC and 0.94 for 99mTc-DMSA scan reporting, using the weighted kappa analysis at P<0.05. CONCLUSIONS: 99mTc-L,L-EC is an excellent single-modality comprehensive investigational agent for renal morphology, function and outflow tract evaluation with the added advantages of lower cost, convenience and low radiation exposure to the patient.  相似文献   
85.
Checketts  MR; Wildsmith  JAW 《CEACCP》2004,4(2):48-51
The last few years have seen increasing concerns among anaesthetistsabout the risks of pharmacological prophylaxis for thromboembolicdisease. Increased bleeding during or after surgery is one concern,but of greater significance is the possibility of an increasedpredisposition to haematoma formation when regional block isused. Most of the recent consideration of this problem has beenin relation to vertebral canal haematoma formation after centralnerve block. Some thought must be given also to the possibilityof haematoma formation after peripheral techniques when thetarget nerve is deeply placed so that pressure cannot be usedto control bleeding after needle insertion. However, this reviewwill be focused on vertebral canal haematoma.  相似文献   
86.
Two case reports of anal cancer developing during chronic therapeutic immunosuppression for systemic lupus erythematosus (SLE) and their cancer management are presented. The complex issues of delivery of curative chemoradiation treatment for anal cancer in the context of co-existing autoimmune connective tissue disease (AICD) are discussed. These two cases show that combined chemotherapy and radiation regimens are possible in patients with SLE. However, frequent, careful assessment with judicious and prompt management of haematological and other complications during treatment is important.  相似文献   
87.
Cardiac calcification usually represents the result of a pathologic process. Some forms of calcification represent chronic change in an ageing population, and must be differentiated from pathologic calcification. Still other forms of calcification are associated with ageing and chronic degeneration, but also reflect ongoing pathologic processes. Recognition of cardiac calcification may be an early sign or only sign of a pathologic process. Characterization of the calcification in terms of its distribution and appearance is a helpful means for determining which structures are calcified, differentiating pathologic from nonpathologic processes. This article provides an overview of the types of calcifications of the heart, pathogenesis, and utility of the various imaging modalities for their detection.  相似文献   
88.
The aim of this study was to isolate and identify antigenic peptides associated with HLA class I molecules on a bladder tumour cell line. HLA-A1 molecules were purified using an immunobead-purification technique and following elution of nonapeptides associated with the complex, their HPLC profile was determined by Tandem mass spectrometry (MS/MS). Three peptides were identified namely: (1) P991 (VTDPGNLLY); (2) P1041.5 (LTDLGFLVY), and (3) P1057.7 (LTDPHLLSY); these sequences matched elements of hepatitis B, MAGE1-A1 and herpes simplex viruses. These antigens had half-lives of approximately 120 min which is within the theoretical range of such short peptides. These results indicate that identification of MHC-associated peptides is possible without using an assay for cytotoxic T cells. Although this approach was applied on a relatively small scale, broader applications can be foreseen.  相似文献   
89.
90.
BACKGROUND: The Centers for Disease Control and Prevention requested that sexually transmitted disease (STD) programs report their current activities and plans to collaborate with managed care organizations in their 1999 applications for federal funding. GOAL: To review CDC STD program applications for funding to assess the number of activities between STD programs and managed care organizations. METHODS: Narrative data on managed care topics were abstracted from 59 funding applications (50 states, 7 cites or counties, and 2 US territories), using standard qualitative methods. A coding system was applied to categorize each managed care activity into one of nine categories (interrater reliability, 93%). An expert panel ranked activities by complexity, and these scores were used to develop an overall complexity score for each program. RESULTS: All but 9 of the 59 applicants reported managed care organization activities. Altogether, 208 activities were specifically documented, 45% of which were classified as operational in 1999. The most frequently reported activities involved gathering and giving information and promoting STD care through legislation and state Medicaid activities. CONCLUSIONS: Considerable information transfer and policy action between STD programs and managed care organizations are taking place. Further integration of services and policies should be studied and encouraged to promote the effective treatment of STD.  相似文献   
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