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Journal of Interventional Cardiac Electrophysiology - Clinical implication of local impedance (LI) for radiofrequency (RF) ablation has not been fully established. This study aimed to investigate...  相似文献   
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With the sandwich binding protein assay utilizing hyaluronic acid binding protein, we measured serum concentration of hyaluronic acid in 458 healthy persons, 71 patients with rheumatoid arthritis (RA) and 51 patients with various rheumatic diseases such as osteoarthritis (OA), progressive systemic sclerosis (PSS), systemic lupus erythematosus (SLE) and gout. The mean concentration +/- standard deviation (SD) of healthy persons whose age ranged 2 to 92 years old was 38.5 +/- 35.7ng/ml, and those with over 50 years old had apparently higher concentrations (51.9 +/- 40.5ng/ml) than those with below 50 of age (20.6 +/- 14.8ng/ml). When the upper limit of normal range was set up at 130 ng/ml, abnormal percentages were 62.0% (44/71) in RA, 0% (0/18) in OA, 6.3% (1/16) in PSS, 18.2% (2/11) in SLE and 0% (0/6) in gout. Patients who apparently had arthritis but not RA revealed normal or near to the upper limit in serum hyaluronic acid compared to RA patients having the mean +/- SD of 351.4 +/- 463.7ng/ml. When patients with RA were classified into stage I to IV with X ray of bone destruction, patients with more advanced X ray stage showed significantly higher serum concentrations of hyaluronic acid. Similarly, patients with lower activity of daily living revealed significantly higher serum concentrations of hyaluronic acid. In addition, serum hyaluronic acid level did correlate to concentration of serum CRP and sialic acid. Lansbury's index, strength of grip, joint score and erythrocyte sedimentation rate, but did not to duration of morning stiffness and titer of rheumatoid factor.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
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The records of 292 patients who were admitted to a teaching hospital from 1984 to 1990 in Uberlandia in southeastern Brazil after being bitten by snakes of the genus Bothrops were retrospectively surveyed. The patients were from 42 municipalities in three states of Brazil. Most (42%) bites occurred between 4:00 PM and 10:00 PM. Fourteen percent of the bites occurred in the month of April. In 54 (18%) of the cases, the snakes were captured and identified as belonging to the following species: B. moojeni (29), B. neuwiedi (18), and Bothrops species (7). A diagnosis was made based on clinical findings in 238 (82%) cases. The lower limbs were the commonest site of bite (74%). The median time interval between bite and admission to the hospital was 3 hr. Fang marks were recorded in 58% of the cases and swelling was recorded in 82%. Clotting time was greater than 15 min in (142 of 264) 54% of the cases. A tourniquet was used on 44 cases. The mean +/- SD dose of specific antivenom used was 187.48 +/- 93.44 mg. The complications that occurred included abscess formation in 18% of the cases, necrosis in 16%, and renal failure in 5%. Amputation was performed in three (1%) cases. The case fatality rate was also 1% (three cases). When all cases were analyzed, the chi-square test for trend showed an increased susceptibility of renal failure with age (P < 0.04). Clotting time greater than 15 min was associated with the development of abscesses (P < 0.02).(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
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Previous studies have shown that external ultrasound with low frequencies and high intensities can enhance thrombolytic drug-induced clot dissolution during in vitro experiments. In this series of studies, we evaluated the efficacy of peripheral and coronary thrombolysis in vivo in animals by using noninvasive transcutaneous ultrasound combined with thrombolytic drugs (streptokinase and tPA) and/or microbubbles agents (dodecafluoropentane [DDFP] and perfluorocarbon-exposed sonicated dextrose albumin [PESDA]). Thrombotic occlusions were induced in 74 rabbit iliofemoral arteries and 24 canine left anterior descending (LAD) coronary arteries in this in vivo study. By using the combination of transcutaneous ultrasound and streptokinase, the angiographic patency rate in rabbit iliofemoral arteries was higher (56%-100%) than with ultrasound (6%; P < or = 0.0036) and streptokinase alone (6%; P < or = 0.0012). Also, with transcutaneous ultrasound and microbubbles, the angiographic patency rates were 76%-100% as compared with ultrasound alone (0%, P < or = 0.0003) or microbubbles alone (9%, P < or = 0.0001). In the canine study of acute myocardial infarction, thrombolysis in myocardial infarction (TIMI) grade flow at 90 minutes in the tPA alone group was 0.92 +/- 1.4 as compared with 2.42 +/- 1.9 in the tPA plus transthoracic ultrasound group (P = 0.006). There was much improved reperfusion with tPA plus ultrasound as compared with tPA alone. In vivo animal studies demonstrate that noninvasive transcutaneous ultrasound can greatly enhance the effect of clot dissolution with thrombolytic drugs and/or microbubbles, and has the potential for clinical application as an adjunctive method to improve arterial thrombolysis.  相似文献   
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Perlman syndrome is a rare, autosomal recessive overgrowth disorder. Recently, the deletion of exon 9 and other mutations of the DIS3L2 gene have been reported in patients; however, the mechanism behind this deletion is still unknown. We report the homozygous deletion of exon 9 of DIS3L2 in a Japanese patient with Perlman syndrome. We identified the deletion junction, and implicate a non-allelic homologous recombination (NAHR) between two LINE-1 (L1) elements as the causative mechanism. Furthermore, the deletion junctions were different between the paternal and maternal mutant alleles, suggesting the occurrence of two independent NAHR events in the ancestors of each parent. The data suggest that the region around exon 9 might be a hot spot of L1-mediated NAHR.  相似文献   
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Oral Radiology - To ascertain the effects of exposure parameters (tube current and tube voltage) and the gutta-percha cone (GPC) size on root fracture-like artifacts obtained with cone-beam...  相似文献   
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OBJECTIVE: To investigate the involvement of osteopontin (OPN) in bone destruction in a murine experimental arthritis model of collagen-induced arthritis (CIA). METHODS: The expression of OPN was examined at both the messenger RNA (mRNA) and protein levels in various arthritic lesions in mice with CIA by in situ hybridization and immunohistochemistry, respectively. In addition, the expression of alpha(v)beta3 integrin, a receptor for OPN, the ligation of which is thought to be essential for bone resorption by osteoclasts, was examined by immunohistochemistry. Plasma concentrations of OPN were measured at different time points in the course of CIA by enzyme-linked immunosorbent assay. RESULTS: OPN mRNA was detected mainly at sites of bone erosion in arthritic lesions, where activated osteoclasts were present; OPN protein was also detected at sites of bone erosion. In the arthritic synovium, OPN was predominantly expressed in the synovial lining layer, but not in lymphoid aggregates. In addition, alpha(v)beta3 integrin was detected coincident with OPN at sites of bone erosion (bone-pannus junction). Plasma OPN levels were markedly elevated at the time points that corresponded to arthritis flares, and higher levels were maintained during the progression of arthritis. CONCLUSION: OPN may mediate bone resorption by osteoclasts in arthritis through ligation with its receptor, alpha(v)beta3 integrin. OPN may be a useful therapeutic target molecule in the prevention of bone destruction in arthritis.  相似文献   
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