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31.
32.
This case report illustrates atypical magnetic resonance (MR) imaging findings in a liver hemangioma mimicking a malignant lesion—lower signal intensity than cerebrospinal fluid on T2-weighted spin-echo images and lack of early enhancement on dynamic contrast material—enhanced gradient-echo images. Pathologic analysis demonstrated nearly total replacement of the vascular cavities by dense fibrous tissue. In this rare, sclerosed form, this lesion could not be defined as a hemangioma with MR imaging.  相似文献   
33.
Evaluative composite measurement scales (CMS) are increasingly used in medicine to measure complex constructs in the absence of a reference criterion or ‘gold standard’. However, the level of measurement provided by these instruments has usually been given little attention. This paper explores the influence of the characteristics of the item set and weighting on the level of measurment of an evaluative CMS. The approach is illustrated with an application to the scoring system of the Nottingham Health Profile. Simulations are provided to indicate when the composite score of item responses, on an ordinal or pass—fail scale, could be considered to achieve the properties of an interval scale.  相似文献   
34.
Thrombosis and thrombolysis in unstable angina   总被引:1,自引:0,他引:1  
Pathophysiology of unstable angina involves spasm, plaque rupture, activation of platelets, and coagulation. The incidence and frequency of intracoronary thrombus formation are presently under active assessment in order to establish the potential benefit of thrombolytic therapy. A preliminary study was conducted in patients admitted in our coronary care unit for unstable angina with typical clinical and electrocardiographic criteria and with early coronary angiogram. After exclusion of 4 patients with left main coronary stenosis or contraindications for thrombolysis, 16 patients received thrombolytic infusion and 14 underwent a second coronary angiogram. Seven patients had an intracoronary thrombus (6 nonocclusive, 1 occlusive) and at the second angiogram only 3 nonocclusive thrombi were modified (1 disappeared, 2 were reduced). Moreover, the quantitative Coronary Angiography Analysis System (CAAS) in the 11 cases suitable for analysis did not show any significant changes, especially in the Ambrose type IIB lesions. In-hospital clinical outcome was not influenced by thrombolytic therapy (5 ischemic recurrences, 1 fatal myocardial infarction, 4 emergency and 4 elective revascularization procedures). This short series is in agreement with the literature data. Only one third of patients with active unstable angina remains refractory to conventional therapy. The transient benefit of thrombolysis is limited to patients with demonstrated intracoronary thrombi. Clinical or angiographic improvement are not always in correlation and until now do not seem able to prevent short-term recurrences or the need for revascularization procedures.  相似文献   
35.
Thirty-five patients hospitalized for recent angiographically documented arterial occlusion in the legs (27 femoropopliteal arteries and eight grafts) benefited from local fibrinolytic therapy delivered at the site of the occlusion with a 4- or 5-F catheter. This therapy combined a continuous urokinase (UK) infusion of 1,000 U/kg/hour and a lysyl plasminogen (LYS-PLG) infusion of 15 microkatals every 30 minutes. Angiographically confirmed lysis was obtained in 85% of the cases. Only 3% of the patients had major and 6% had minor groin hematomas. Only two patients had concentrations of fibrinogen as low as 100 mg/dl. Intravascular infusion of UK-LYS-PLG is as effective as streptokinase. Its excellent tolerance makes it a good alternative in the treatment of acute ischemia in the lower limbs.  相似文献   
36.
A 28-year-old mentally retarded, institutionalised woman was referred to us for evaluation of multiple plantar warts and ingrown nails of both great toes. The patient was born to unrelated parents of North African origin and had one brother and three half-brothers, all of whom were healthy. Physical examination revealed short stature, slight obesity, facial abnormalities (Fig. 1), short and broad thumbs and big toes (Figs. 2 and 3). A keloid was found on the right forearm, that had developed after surgical correction of a fracture (Fig. 4). Ill-defined hyperpigmented macules were observed on the trunk. The patient also presented pruritic eczematous lesions of the limbs and the back that had been present for some years and were recurrent despite treatment with emollients and local steroids. Androgenetic-type alopecia of moderate severity was seen on the vertex of the scalp. Past medical history included polydactylism of the feet and clinodactyly of the thumbs (both corrected surgically), respiratory tract infections, Wolf-Parkinson-White syndrome and refractive errors necessitating glasses.  相似文献   
37.
Purpose To determine the efficacy of a cystoscopic approach, as definitive treatment of ureteral fistulae, after failure of antegrade ureteral stent insertion.Methods Of 43 ureter fistulae encountered over 4 years, 10 postoperative and/or postradiotherapy fistulae could not be stented via an antegrade approach alone. A cystoscopic approach was used, with the antegrade approach available as back-up, if necessary.Results In two patients the ureteral orifice could not be visualized cystoscopically, thus precluding the retrograde approach. In the eight remaining patients, the retrograde approach alone never allowed successful stenting. In six patients, combined antegrade and retrograde approaches permitted stent insertions. In three of those six patients, a complex catheterization procedure was necessary. In two patients the combined approach failed altogether. Therefore, 6 of 10 patients underwent a successful stenting procedure with the combined approach; all ultimately closed the fistula.Conclusion Antegrade stent insertion remains the treatment of choice for ureteral leaks. If the antegrade approach fails, the retrograde approach alone is not likely to be successful. Instead, a combination of both approaches often does succeed.  相似文献   
38.
The polymerization of lactides with various D /L enantiomeric compositions using achiral Schiff's base/aluminium methoxide as initiator (SALENAlOCH3) in dichloromethane solution at 70°C is reported. The conversion was kept below 70% in order to limit transesterification reactions. The polymers obtained after precipitation show a narrow molecular weight distribution (ratio of weight- to number-average molecular weights M w/M n = 1,1–1,2) and an optical rotation higher than that expected from the optical purity of the starting monomers. The examination of the thermal properties reveals that whatever their enantiomeric composition all the prepared polymers are crystalline. This unusual behavior is explained by an end-chain propagation mechanism producing stereocopolymers with long enantiomeric sequences, i.e., increased isotacticity as substantiated by an examination of the microstructure of the polymers by means of 13C nuclear magnetic resonance. A stereocomplex formation was observed for stereocopolymers with optical purities below 40%.  相似文献   
39.
The diagnosis of nontraumatic intracranial hemorrhage is currently made by computed tomography and is rarely problematic. The causes of bleeding are very numerous. It is important to determine the cause of the hemorrhage promptly, because there may be a recurrence of bleeding. Guidelines for radiologists are proposed and discussed here.  相似文献   
40.
OBJECTIVES: This article examines the differences found between clientele with severe mental health problems and their key health workers in terms of assessing service users' needs in 6 Quebec service areas. METHOD: We questioned 165 pairs of users and staff, using the Camberwell Assessment of Needs questionnaire. The profile of serious and overall problems encountered by clientele from each of the sites was compared. RESULTS: The sites with the greatest degree of user-staff agreement in identifying problems were also the ones where users considered that local services best met their needs. CONCLUSIONS: The study demonstrated that, in needs assessment, major differences exist between the perceptions of users and their key workers in the various sites. These differences can be explained in part by users' individual characteristics, by types of needs, by local particularities, and by service use.  相似文献   
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