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BACKGROUND: Endovascular radiofrequency obliteration has been used since 1998 as an alternative to conventional vein stripping surgery for elimination of saphenous vein insufficiency. OBJECTIVE: To demonstrate the long-term efficacy of this treatment modality. METHODS: Data were prospectively collected in a multicenter ongoing registry. Only great saphenous vein above-knee treatments were included in this study. Eight hundred ninety patients (1,078 limbs) were treated prior to November 2003 at 32 centers. Clinical and duplex ultrasound follow-up was performed at 1 week, 6 months, and 1, 2, 3, and 4 years. RESULTS: Among 1,078 limbs treated, 858 were available for follow-up within 1 week, 446 at 6 months, 384 at 1 year, 210 at 2 years, 114 at 3 years, and 98 at 4 years. The vein occlusion rates were 91.0%, 88.8%, 86.2%, 84.2%, and 88.8%, respectively; the reflux-free rates were 91.0%, 89.3%, 86.2%, 86.0%, and 85.7%, respectively; and the varicose vein recurrence rates were 7.2%, 13.5%, 17.1%, 14.0%, and 21.4%, respectively, at each follow-up time point at 6 months, and 1, 2, 3, and 4 years. Patient symptom improvement persisted over 4 years. CONCLUSIONS: Endovascular temperature-controlled radiofrequency obliteration of saphenous vein reflux exhibits an enduring treatment efficacy clinically, anatomically, and hemodynamically up to 4 years following treatment.  相似文献   
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The effect of specific glycosaminoglycan-hydrolyzing enzymes on the ruthenium red staining of pig spermatozoa was studied. Washed spermatozoa were incubated at 35 degrees C in buffer or with neuraminidase 0.5 units/ml, heparinase 0.2 mg/ml, or chondroitinase ABC 2.0 units/ml. After incubation sperm cells were washed, stained with ruthenium red and studied under the electron microscope. Anionic sites in the surface of untreated spermatozoa follow regularly the plasma membrane, but present are numerous processes constituting what has been defined as the glycocalyx. Neuraminidase did not affect the distribution of ruthenium red on the surface of the spermatozoa, but eliminated almost completely the processes of the glycocalyx. Heparinase caused loss of the ruthenium red-stained sites on the membrane surface of pig spermatozoa with less influence on the dense processes of the glycocalyx. A similar loss of ruthenium red-stained sites was observed with nitrous acid treatment. A striking effect of treatment with chondroitinase ABC was the production of a typical acrosome reaction.  相似文献   
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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   
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To assess the value of unbound bilirubin (UB) and saturation index (SI) in serum and CSF as indicators of Kernicterus, we studied 50 icteric neonates (serum indirect bilibrubin (IB) greater than or equal to 7 mg/dl) and 20 controls (IB less than 7 mg/dl) during the first week of life. Serum and CSF were obtained simultaneously in all neonates. Of 36 neonates with IB greater than 12 mg/dl 19 had evidence of kernicterus. UB was estimated by Sephadex gel filtration and SI by salicylate displacement technique. Positive correlation (r = +0.85) was obtained between serum and CSF UB levels. There was a significant difference (p less than 0.05) between mean serum and CSF UB levels in kernicterus and non-kernicterus neonates (kernicterus serum UB = 0.71 +/- 0.22) mg/dl, CSF UB = 0.16 +/- 0.06 mg/dl: non-kernicteric serum UB = 0.40 +/- 0.10 mg/dl, CSF UB = 0.10 +/- 0.03 mg/dl). A critical serum UB level 0.5 mg/dl and a danger zone of CSF UB (0.1 to 0.15 mg/dl) was observed in presence of kernicterus. Neonates with kernicterus and 30% non-kernicteric had serum SI greater than or equal to 8. Mean values of serum and CSF SI were comparable in all neonates. The serum and CSF UB and SI, and the mean percentage cross over of UB from serum to CSF when statistically compared were not significantly influenced by risk factors.  相似文献   
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Unsterile polyvinyl, regular latex, and powder-free, modified latex examination gloves were evaluated following usage in routine dental procedures to assess their loss of integrity. Glove fingers were filled with a suspension of red-pigmented Serratia marcescens and drawn across the surface of tryptic soy agar plates. The appearance of red-pigmented Serratia colonies on the plates was used as an indication of glove defects. Unused, unwashed gloves taken at random from boxes served as controls. Of the gloves used in clinical procedures, 83.3% of the polyvinyl gloves, 35.0% of the regular latex gloves, and 7.5% of the powder-free, modified latex gloves allowed penetration of Serratia. Data thus suggest that advances in technology continue to develop a glove with more resistance than regular latex and vinyl gloves to routine clinical usage.  相似文献   
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