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51.
BACKGROUND: Although chronic total occlusions are encountered frequently in patients with coronary artery disease, an effective strategy to deal with them has yet to be devised. Various new guidewires have been designed in an attempt to negotiate chronic occlusions successfully. The authors have analysed the impact of the Athlete guidewire on procedural success in this lesion subset. METHODS: Sixty-two consecutive patients undergoing percutaneous intervention for chronic total occlusions over a twoyear period were retrospectively studied. For the initial attempt, conventional guidewires were used. In case of failure, further attempts were made using the Athlete guidewire. Procedural success rates with the use of conventional and Athlete guidewires were assessed. RESULTS: Failure of the first attempt with the conventional guidewire occurred in 32 (51.6%) patients and success was achieved in 30 (48.4%) patients. In the former patients, a second attempt was made using the Athlete guidewire to cross the occlusion. The second attempt was successful in 20 patients (60%) in whom the first attempt was unsuccessful, while in the remaining 12 (40%) patients the occlusion could not be crossed even during the second attempt and the procedure was then terminated. Following the use of the Athlete guidewire, the success rate increased to 62% ( p < 0.001). No complication occurred during the first attempt, while one patient had a coronary perforation using the Athlete guidewire, which was managed successfully without the need for bypass surgery. CONCLUSION: The use of the Athlete guidewire is feasible and safe, and enhances the chances of successfully treating chronic total occlusions during percutaneous coronary revascularization procedures. (Int J Cardiovasc Intervent 2000; 3: 105-110)  相似文献   
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Background  

Although not as common as in women, osteoporosis remains a significant health care problem in men. Data concerning risk factors of osteoporosis are lacking for the male Moroccan population. The objective of the study was to identify some determinants associated to low bone mineral density in Moroccan men.  相似文献   
53.
Purpose: Thermal injury during implant bed preparation has a major influence on implant osseointegration and survival. This study investigated the effectiveness of the temperature of the saline solution used for heat control during drilling.
Material and methods: Fresh frozen edentulous segments of bovine mandibles were sectioned into 12 × 6 cm pieces. Thermoresistors were placed 0.5 mm from the drilling cavity walls, at depths of 3, 7, and 12 mm. Signals from the three thermoresistors were analyzed using ORIGIN 5.0 software.
Results: The maximum temperatures during drilling without irrigation were 50.9, 47.4, and 38.1°C at depths of 3, 7, and 12 mm, respectively. With irrigation using saline at 25 and 10°C, the maximum temperatures at a depth of 12 mm were 37.4 and 36.3°C, respectively. All other measurements with both 25 and 10°C saline were below body temperature.
Discussion and conclusion: This experimental in vitro study showed that more heat was generated in the superficial part of the drilling cavity than at the bottom. Therefore, external irrigation at room temperature can provide sufficient cooling during drilling. Lower temperature saline was more effective in cooling the bone, and irrigation of the site should be continued between the drilling steps.  相似文献   
54.
BACKGROUND: Intravascular stents are increasingly being used to treat subclavian artery obstructive disease. This study aimed to assess the immediate and midterm clinical outcome of subclavian artery stenting. METHODS AND RESULTS: Total occlusion of the subclavian artery was seen in 7 (28%) out of the 25 consecutive patients treated for subclavican artery stenosis. Mean lesion length was 14 &#45 4.3 mm. The mean preprocedure diameter stenosis was reduced from 83.2 &#45 14.9% to 9.6 &#45 5.4% postprocedure. success was achieved in all patients. Clinical follow-up was obtained in all patients. The initial success was maintained at follow-up (mean = 12 &#45 4 months) in 24 (96%) patients. Recurrence of symptoms occurred in 1 (4%) patient who had an angiographically documented restenosis four months after the procedure. It was successfully redilated. CONCLUSION: Stenting for subclavian artery obstructive disease is safe, technically feasible and has favorable clinical outcomes. It may be considered as the therapy of choice for subclavian artery Procedural obstructive disease. (Int J Cardiovasc Intervent 2000; 3: 231-235)  相似文献   
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Polyamines are unbiquitous, naturally occurring small aliphatic, polycationic, endogenous compounds. They are involved in many cellular processes and may serve as secondary or tertiary messengers to hormonal regulation. The relationship of polyamines and skeletal muscle mass of adductor longus, extensor digitorum longus, and gastrocnemius under unloading (hindlimb suspension) conditions was investigated. Unloading significantly affected skeletal muscle polyamine levels in a fiber-type-specific fashion. Under loading conditions, clenbuterol treatment increased all polyamine levels, whereas under unloading conditions, only the spermidine levels were consistently increased. Unloading attenuated the anabolic effects of clenbuterol in predominately slow-twitch muscles (adductor longus), but had little impact on clenbuterol's action as a countermeasure in fast- twitch muscles such as the extensor digitorum longus. Spermidine appeared to be the primary polyamine involved in skeletal muscle atrophy/hypertrophy.  相似文献   
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Background

Bilharzia-associated bladder cancer (BAC) is a major health problem in countries where urinary schistosomiasis is endemic. Characterization of the genetic alterations in this cancer might enhance our understanding of the pathogenic mechanisms of the disease but, in contrast to nonbilharzia bladder cancer, BAC has rarely been the object of such scrutiny. In the present study, we aimed to characterize chromosomal imbalances in benign and malignant post-bilharzial lesions, and to determine whether their unique etiology yields a distinct cytogenetic profile as compared to chemically induced bladder tumors.

Methods

DNAs from 20 archival paraffin-embedded post-bilharzial bladder lesions (6 benign and 14 malignant) obtained from Sudanese patients (12 males and 8 females) with a history of urinary bilharziasis were investigated for chromosomal imbalances using comparative genomic hybridization (CGH). Subsequent FISH analysis with pericentromeric probes was performed on paraffin sections of the same cases to confirm the CGH results.

Results

Seven of the 20 lesions (6 carcinomas and one granuloma) showed chromosomal imbalances varying from 1 to 6 changes. The most common chromosomal imbalances detected were losses of 1p21-31, 8p21-pter, and 9p and gain of 19p material, seen in three cases each, including the benign lesion.

Conclusion

Most of the detected imbalances have been repeatedly reported in non-bilharzial bladder carcinomas, suggesting that the cytogenetic profiles of chemical- and bilharzia-induced carcinomas are largely similar. However, loss of 9p seems to be more ubiquitous in BAC than in bladder cancer in industrialized countries.
  相似文献   
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