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Four-Year Follow-up on Endovascular Radiofrequency Obliteration of Great Saphenous Reflux 总被引:4,自引:0,他引:4
Merchant Robert F. MD Pichot Olivier MD † Myers Kenneth A. MD ‡ 《Dermatologic surgery》2005,31(2):129-134
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
3.
J T Muldoon L A Wintermeyer J A Eure L Fuortes J A Merchant S F Van Lier T B Richards 《American journal of public health》1987,77(8):1006-1008
Health department epidemiologists in 50 states, New York City, and the District of Columbia were surveyed in 1985 about seven potential data sources for occupational disease surveillance. Reported sources of occupational disease data were: automated workers' compensation claims (63 per cent of the 52 respondents); provider reports (62 per cent); death certificates with occupation or industry (60 per cent); cancer registries with occupational histories (35 per cent); birth certificates with parent's occupation (27 per cent); non-cancer disease registries (13 per cent); and hospital or insurance records (8 per cent). 相似文献
4.
N M Delgado R Reyes A Carranco L Huacuja H Merchant A Rosado 《Archives of andrology》1990,25(2):121-129
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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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
9.
J Saunders M Cassidy S B Freedman E A Harley L L Iversen C Kneen A M MacLeod K J Merchant R J Snow R Baker 《Journal of medicinal chemistry》1990,33(4):1128-1138
Recent clinical studies on Alzheimer's patients have implied that only agents displaying high efficacy at the cortical muscarinic receptor have yielded encouraging results. This paper describes the design, synthesis, and biochemical characterization of novel quinuclidine-based muscarinic agonists which can readily penetrate into the central nervous system and which are capable of displaying high efficacy at cortical sites. With use of a biochemical assay capable of measuring receptor affinity and predicting cortical efficacy, it has been discovered that an oxadiazole ring and related heterocycles can function as bioisosteric replacements for the ester moiety found in several known muscarinic ligands. Within this series there exist compounds which span the efficacy range from high-efficacy agonist through partial agonists to antagonists with affinity comparable or superior to that of classical quaternary ammonium ligands. Consistent with recent molecular biology studies, structure-activity trends are interpreted in terms of separate binding sites for agonists and antagonists with H-bonding interactions characterizing agonist behavior and lipophilic binding characterizing antagonist behavior. Thus the aminooxadiazole moiety has structural features which are optimized for an agonist profile. 相似文献
10.
Calciphylaxis – a topical overview 总被引:3,自引:0,他引:3
G Arseculeratne† AT Evans‡ SM Morley† 《Journal of the European Academy of Dermatology and Venereology》2006,20(5):493-502
'Calciphylaxis', a calcification syndrome associated with ischaemic cutaneous necrosis, is acquired naturally in humans in disease states. It is a life and limb-threatening complication, usually observed in patients with renal disease and secondary hyperparathyroidism, but known to occur in the absence of renal or parathyroid disease. The reported mortality rate, which ranges from 60-80%, relates to wound infection, sepsis and organ failure. It is a small-vessel vasculopathy, which is estimated to occur in about 4% of haemodialysis patients. Clinically, violaceous, reticulate areas of cutaneous necrosis and eschar may be evident, particularly in the extremities. In addition to the clinical picture, a raised calcium phosphorous product, an elevated parathyroid hormone level, radiographic evidence of vessel and soft-tissue calcification and the finding of mural calcification affecting small arteries and arterioles on histopathology help to confirm the diagnosis of this entity which generally has a poor prognosis. A high index of suspicion and an active multidisciplinary management approach, with rigorous attention to wound care and prevention of sepsis, are vital in the management of these patients. In this overview, we discuss the pathophysiology, clinical features and associations, risk factors, diagnosis and management issues relating to calciphylaxis. 相似文献