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991.
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OBJECTIVES: The authors evaluated the experience and results of a single center in surgical treatment of proximal bile duct carcinoma. SUMMARY BACKGROUND DATA: Whenever feasible, surgery is the appropriate treatment in proximal bile duct carcinoma. To improve survival rates and with special regard to liver transplantation, the extent of surgical radicalness remains an open issue. PATIENTS AND METHODS: Retrospective analysis of 249 patients who underwent surgery for proximal bile duct carcinoma via the following procedures: resection (n = 125), liver transplantation (n = 25), and exploratory laparotomy (n = 99). Survival rates were calculated according to the Kaplan-Meier method, uni- and multivariate analysis of prognostic factors, and log rank test (p < 0.05). RESULTS: Survival rates after resection and liver transplantation are correlated with international Union Against Cancer (UICC) tumor stage (resection: overall 5-year, 27.1%; stage I and II, 41.9%; stage IV, 20.7%; liver transplantation: overall 5-year, 17.1%; stage I and II, 37.8%; stage IV, 5.8%). Significant univariate prognostic factors for survival after liver resection were lymph node involvement (N category), tumor stage, tumor-free margins, and vascular invasion; for transplantation, they were local tumor extent, N category, tumor stage, and infiltration of liver parenchyma. For resection and transplantation, a multivariate analysis showed prognostic significance of tumor stage and tumor-free margins. CONCLUSION: Resection remains the treatment of choice in proximal bile duct carcinoma. Whenever possible, decisions about resectability should be made during laparotomy. With regard to the observation of long-term survivors, liver transplantation still can be justified in selected patients with stage II carcinoma. It is unknown whether more radical procedures, such as liver transplantation combined with multivisceral resections, will lead to better outcome in advanced stages. With regard to palliation, surgical drainage of the biliary system performed as hepatojejunostomy can be recommended.  相似文献   
993.
WIPL is a program which allows fast and accurate analysis of antennas. The geometry of any metallic structure (even a very large structure) is defined as a combination of wires and plates. WIPL's analysis features include evaluations of the current distribution, near and far field, and impedance, admittance and s-parameters. The program uses an entire-domain Galerkin method. Efficiency of the program is based on the flexible geometrical model, and sophisticated basis functions. In this paper, the basic theory implemented in the program, and some results concerning TV UHF panel antennas and large horn antennas are given  相似文献   
994.
INTRODUCTION: The aim of the study was the evaluation of the usefulness of transesophageal atrial pacing in predicting chronic oral treatment efficacy of symptomatic reciprocating supraventricular tachycardia in infants and in avoiding the risk of very dangerous recurrences at home. METHODS: We studied 13 infants (11 males, 2 females, mean age 43 +/- 31 days) with symptomatic reciprocating supraventricular tachycardia and no structural heart disease. All patients had chronic oral therapy, using the drug effective in acute i.v. somministration. Each patient was discharged when supraventricular tachycardia was not inducible with transesophageal atrial pacing after 5 half-lives of the drug used in chronic oral treatment. All patients, every 6 months, were retested with transesophageal atrial pacing alternatively during chronic oral therapy and after complete wash out. Oral therapy was stopped in each patient when supraventricular tachycardia was not inducible after the wash out. RESULTS: The number of oral treatments tested for each patient were 2 +/- 1 (range 1-5). The number of transesophageal studies performed for each patient were 4 +/- 2 (range 3-7). No patient had symptomatic episodes of supraventricular tachycardia or needed to change therapy during the follow-up. The oral treatment was stopped after the twelfth month of life in 8 patients and after the twenty-fourth in 2 others without recurrences. CONCLUSION: Transesophageal atrial pacing seems to be useful in predicting accurately and rapidly the oral treatment efficacy of supraventricular tachycardia in infants. Our protocol seems to be effective to avoid dangerous recurrences of tachycardia and to decide when we can stop therapy without risk.  相似文献   
995.
OBJECTIVES: To compare the effects of dry needling of myofascial trigger points in the neck region to metoprolol in migraine prophylaxis. DESIGN: Randomized, group comparative study. patients, investigator and statistician were blinded as to treatment, the therapist was blinded as to results. SETTING: Outpatient pain clinic in the northern Copenhagen area. Patients were referred by general practitioners or respondents to newspaper advertisements. SUBJECTS: Included were patients with a history of migraine with or without aura for at least 2 years. Excluded were persons with contraindications against treatment with beta blockers, chronic pain syndromes, pregnancy or previous experience with acupuncture or beta-blocking agents. A total of 85 patients were included; 77 completed the study. INTERVENTIONS: After a 4-week run-in period, patients were allocated to a 17-week regimen either with acupuncture and placebo tablets or to placebo stimulation and metoprolol 100 mg daily. RESULTS: Both groups exhibited significant reduction in attack frequency (P < 0.01). No difference was found between the groups regarding frequency (P > 0.20) or duration (P > 0.10) of attacks, whereas we found a significant difference in global rating of attacks in favour of metoprolol (P < 0.05). CONCLUSIONS: Trigger point inactivation by dry needling is a valuable supplement to the list of migraine prophylactic tools, being equipotent to metoprolol in the influence on frequency and duration (but not severity) of attacks, and superior in terms of negative side-effects.  相似文献   
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The increasing recognition of the importance of emotional state in both disease and health makes imperative the need for health care providers to evaluate the psychological status of patients. In primary care medical practice, between 30 and 60% of complaints prompting visits to the physician's office have a significant emotional component. In addition, rates of depressive illness are estimated to be as high as 20% in the general population. Prompt recognition of anxiety, depression, personality disorder, and psychosis is important for correct interpretation of historical and physical findings during examination and evaluation of patients. The establishment of a caring and trusting relationship is crucial so that patients can comfortably express concerns, and so that a discussion leading to an agreeable therapeutic plan can be decided upon. This process has traditionally taken place in the one-on-one format between the health care provider and patient. Many physicians and therapists are interested in exploring whether virtual reality can augment the therapeutic process, and thus improve diagnostic capabilities  相似文献   
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