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11.
The beStent is a new stainless steel, balloon-expandable mesh stent which has a unique serpentine design. Rotation of the unique low stress junctions upon expansion leads to orthogonal locking of the wires, maximizing radial strength and assuring zero shortening. The stent has delineating gold markers which assure precise positioning. We aim to present the initial acute results in a pilot registry for stent evaluation. Two hundred eighty-four stents were used in a total of 217 patients (age 57.9 ± 3.10 years; 178 males; 39 females) in seven centers, for variable indications. Stents of 15-, 25-, and 35-mm length were used. The arteries treated were the left anterior descending (n = 112, 42%), circumflex (n = 54, 20.2%), right coronary (n = 95, 35.5%), left main (n = 1, 0.4%), and vein graft (n = 5, 1.9%). Lesion types were: A in 42 patients (16.5%); B1 in 53 patients (20.7%); B2 in 81 patients (31.8%); and C in 79 patients (31%). One hundred fifty-nine patients required one stent, 40 patients required two stents, and 18 patients required three or more stents. Anticoagulation protocol included procedural heparin with aspirin with/without ticlopidine. Smooth angiographie results were obtained in all cases with no plaque herniation. Acute angiographic success was obtained in 97% of the patients, and acute clinical success in 95% of the patients. Complications within 30 days were: 3 deaths (1.4%) (2 noncardiac); 2 (0.9%) myocardial infarctions; and 2 (0.9%) stent thromboses. Therefore, the beStent is useful in treatment of complex lesions of variable length and complexity, providing excellent acute results with a low complication rate, in spite of unfavorable basic clinical and angiographie characteristics.  相似文献   
12.
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   
13.
The relationship between maternal age and cesarean section in low-risk nulliparas was analysed in 7454 perinatal clinical records selected from eleven databases of Latin American institutions obtained with a comprehensive perinatal information system. The risk of cesarean section in nulliparas between 29 and 49 years of age was found to be three times higher than that corresponding to pregnant women of lesser age. This clearly more aggressive obstetrical conduct could not be explained by the main indications for cesarean section.  相似文献   
14.
Three cases of popliteal artery entrapment syndrome, one of them bilateral, are presented with a review of the literature, with special reference to the embryological development of the popliteal space and the diagnostic and therapeutic problems presented by this syndrome.  相似文献   
15.
AIMS: To estimate the prevalence of diabetes mellitus with three diagnostic criteria (WHO-1985 and 1999 and ADA-1997), evaluate their concordance and analyse the sensitivity and specificity of the different screening strategies for diabetes. METHODS: A cross-sectional population study with two-step sampling. One thousand and 34 people were selected randomly. A 75-g oral glucose tolerance test (OGTT) was performed and venous blood samples were obtained fasting and at 2 h. RESULTS: The prevalence of known Type 2 diabetes mellitus (DM-2) is 4%[95% confidence interval (CI) 2.8, 5.1]. By WHO-1985 criteria the prevalence of unknown DM-2 is 5.9% (4.5, 7.4); by ADA-1997 criteria 3.5% (2.5, 4.6) and by WHO-1999 criteria 7.3% (5.8, 8.8). Diagnostic overlap and statistical concordance (coefficient K) are WHO-1985/ADA-1997 29.3%, K=0.42; WHO-1985/WHO-1999 80%, K=0.88; ADA-1997/WHO-1999 48%, K=0.63. If only fasting glucose was used (following ADA-1997), 36.3% of those with diabetes (2-h glucose > or =11.1 mmol/l) would be diagnosed. If OGTT was performed (i) in those with a fasting glucose between 6.1 mmol/l and 6.9 mmol/l (9.8% of the population) we would diagnose 66.6%, and (ii) in all those between 5.7 mmol/l and 6.9 mmol/l (18.9% of the population) 81.8% would be diagnosed. CONCLUSIONS: The ADA criteria decrease the prevalence of DM in the adult population of Asturias by 2.4% and concordance with the classical criteria (WHO-1985) was only 29.3%. Using fasting glucose only (ADA-1997) diagnoses 36.3% of those with diabetes. The recent recommendations of the WHO-1999 increases this to 66.6%. To improve the diagnostic strategy for diabetes and detect up to 81.8% of patients, we propose the use of OGTT for all those with a fasting glucose between 5.7 mmol/l and 6.9 mmol/l.  相似文献   
16.
Blood flow pattern recording of hepatic veins using pulsed Doppler technique is a valid method for the assessment of hemodynamic changes in right atrium. We describe a patient with severe aortic regurgitation secondary to acute infective endocarditis who underwent surgical repair. Before surgery and during the postoperative period, several evolutive studies (including conventional echo and hepatic veins pulsed Doppler recordings) were performed. The different central blood flow patterns were correlated with changing hemodynamic conditions during follow-up of the patient. These central flow velocities reflect changes in right atrial pressure contours, and are easily obtained non-invasively with pulsed wave Doppler ultrasound of the hepatic veins. They could be an useful method for assessing right heart filling dynamics, reporting characteristic patterns in other cardiac disease states.  相似文献   
17.
The antiviral/antitumor marine alkaloid dercitin was used as a lead compound to design analogues with anti-HIV and tumor inhibitory activities. Deletion of structural features contributing to cytotoxicity led to analogues with lowered T-lymphocyte toxicity profiles. One compound, 5, induced complete protection against HIV-1 infectivity in vitro at 12.5 micrograms/mL (38 microM) without T-cell toxicity up to 400 micrograms/mL. Compound 4 and 5 also inhibited the binding of HIV-1 to H-9 lymphocytes. These compounds may exert antiviral activity by a unique dual extracellular and intracellular mode of action--both preventing viral attachment to lymphocytes as well as intercalating with viral nucleic acid. Analogues with higher cytotoxicity such as 2 which retain the thiazole ring of the natural product proved effective in completely inhibiting the cell proliferation of breast, colon, and lung tumor cell lines at 1.5 microM concentration compared to a 70 microM dose level of 5-fluorouracil. A means of molecular separation of antiviral activity from cytotoxicity was thus achieved, and putative pharmacophores for antiviral and antitumor actions of the prototype molecule dercitin have been deduced. The 2-thio-9-acridinone derivatives 4 and 5 represent a new structural type exhibiting activity against HIV in vitro, serving as chemical leads in the design of anti-AIDS agents, while thiazolo[5,4-b]acridines such as 2 provide leads in the drug design of new antitumor agents.  相似文献   
18.
This paper presents a method of improving the TLD-100 dose reassessment performance. This method consists of applying numerical analysis techniques for evaluating the TLD-100 phototransferred thermoluminescence (PTTL) glow curve. From this analysis, a simple procedure for estimating the ultraviolet background components usually present in phototransferred thermoluminescence (TL) signals has been established. This procedure has been implemented in a computer program which performs the automatic evaluation of the glow curves and extracts the dose information contained in the PTTL curves. The use of this computer-aided evaluational method has enabled the extension of the working range of estimated absorbed dose down to 0.2-0.5 mGy with very adequate operational quality for doses even below the conventionally admitted lower reestimation limit (approximately 2 mGy). Because TL readout is a destructive process, the ability to reestimate doses can be important in any kind of dosimetric activity, such as operational dosimetry programs. The other commonly used dosimeter, film, uses a nondestructive readout and, therefore, presents some advantages over TLD when dose reassessment is necessary. With the reported improvements in the TLD-100 dose reassessment performance, the full range of absorbed doses covered by film dosimetry can now be reliably reassessed using TLD-100 dosimeters.  相似文献   
19.
20.
We present a patient with human immunodeficiency virus (HIV) infection coincident with diffuse nodular regenerative hyperplasia (DNRH) of the liver and visceral leishmaniasis. This association has not been previously described. Some DNRH cases are secondary to irregular blood flow in the liver. In the presently described case, there exist two possible conditioning factors for heterogenous distribution of blood flow: 1) the increased blood flow from splenomegaly, and 2) the irregular circulation of blood through sinusoids infiltrated by Leishmania -parasitized hyperplastic macrophages.  相似文献   
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