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991.
Nonsurgical repositioning of central venous catheters   总被引:2,自引:0,他引:2  
Lois  JF; Gomes  AS; Pusey  E 《Radiology》1987,165(2):329-333
Long-term central venous catheters are placed for total parenteral nutrition and/or chemotherapy. These catheters are placed surgically and fixed to the subcutaneous tissues. Complications include infection, venous thrombosis, and mechanical problems. The authors developed a method to percutaneously reposition displaced central venous catheters. The procedure is performed with fluoroscopy and modified angiographic techniques. Fifteen patients underwent a total of 17 procedures. The initial success rate was 76%; the final success rate was 88%. Many central venous catheters can be salvaged with this low-morbidity procedure, which negates the need for surgical intervention.  相似文献   
992.
Synovial sarcomas are rare soft tissue tumors which histopathologically can be divided into monophasic, biphasic and mixed variants. As part of a protocol for intra-arterial chemotherapy 12 patients with biopsy proven synovial sarcoma underwent angiography. The angiograms on these patients were reviewed to determine whether synovial sarcomas and their variants demonstrated a characteristic angiographic appearance. Synovial sarcomas appeared angiographically as soft tissue masses which showed a fine network of tumor vessels with an inhomogeneous capillary blush. Their degree of vascularity varied according to their histopathology. Monophasic synovial sarcomas demonstrated in general a higher degree of neovascularity than the biphasic form. This finding was also suggested by histopathologic analysis of the vessels in the tumor. Although angiography did not show a distinctive vascular pattern it may be useful to evaluate tumor size and vascularity.  相似文献   
993.
994.
The need for new cardiovascular risk factors, due to the limitations of traditional factors, is pointed out. Recent views regarding the role of inflammation in the evolution of the atherosclerotic process, namely in the formation of the atheroma plaque, its progression and rupture, and initiation of acute coronary events, are briefly summarized. These events point to the possibility that inflammatory markers could constitute new markers of cardiovascular risk. Amongst them, C-reactive protein (CRP)--particularly high sensitivity CRP (hsCRP)--has been found to be a 'golden marker' in this field. Data are presented indicating that CRP, rather than being merely an epiphenomenon of inflammation, in fact constitutes a pathogenic agent of the atherosclerotic process. The importance of CRP elevation in acute coronary events, in revascularization interventions, in other situations of cardiovascular risk and even in apparently healthy individuals is outlined. The performance of CRP is then compared with that of traditional risk factors. Finally, the need for studies to discover whether a decrease in CRP levels, as obtained with several pharmacological agents, is accompanied by a simultaneous reduction of cardiovascular risk is emphasized.  相似文献   
995.
Oral forces applied to human teeth during biting and mastication are normally described in the literature only in terms of their axial components. The purpose of this study was to fully determine the spatial characteristics of the oral resultant force – its normal and tangential components - for a given individual. A load cell was especially manufactured to measure oral force and was temporarily implanted as a prosthetic device in the dental arch of a volunteer, replacing his missing upper first molar. The mastication and occlusion tests were carried out in such a way the cell should withstand the loads applied to the molar, and its state of strain was recorded by strain gauges attached to it. Based on the results of these tests and using balance equations, normal and tangential components of the resultant oral force were determined. For direct occlusion, without interposition any obstacle between cusps, a peak normal force of 135 N was recorded simultaneously to a tangential force of 44 N. For mastication of biscuits, a peak normal force of 133 N and a tangential force of 39 N were obtained.  相似文献   
996.

Background  

The presence of cancer makes it difficult to predict the progress of pregnancy and can be deleterious to the maternal-foetal relationship. Apoptosis may affect a range of placental functions and result in the retardation of foetal growth. In this work, we investigated the placental alterations produced by tumour growth and the effects on the expression of apoptotic factors in placental tissue.  相似文献   
997.
998.
Fourteen root perforations were performed for microscopic evaluation of the repair of interradicular tissue in dogs'' teeth. These perforations were accomplished at low-speed with a STP 58 bur at the cervical third of the mesial root toward the furcation under irrigation with saline solution, followed by immediate sealing with ProRoot MTA, MTA-Angelus and white Portland cement. The dogs were killed after 90 days, revealing good results. The Kruskal-Wallis test did not demonstrate any statistically significant difference. It was concluded that the three materials showed good sealing in mineralized tissue, with complete closure, and they were free of inflammation in most teeth.  相似文献   
999.
OBJECTIVE: To use demographic and clinical data to identify the clinical pattern that best predicts the diagnosis of carpal tunnel syndrome (CTS), as defined by neurophysiologic studies. METHODS: A diagnostic cross-sectional study in 2535 consecutive patients (3907 upper limbs) older than 12 years old who were referred for nerve conduction studies in the upper limbs between August 2001 and January 2003 in 3 university hospitals and 2 private neurophysiology services in the state of Rio Grande do Sul, Brazil. RESULTS: A neurophysiologic diagnosis of CTS was established in 39.1% of these upper limbs. The presence of paresthesias or pain at least 2 of the first 4 digits in association with one of the following: female gender, symptoms worsening at night or on awakening, an BMI > or =30, thenar atrophy, or other sign (Tinel's, Phalen's, or Reversed Phalen's signs); were the best pattern associated with the diagnosis. CONCLUSIONS: We have found that the clinical picture alone does not seem sufficient, in majority of the population, to correctly predict the diagnosis of CTS, as defined by median nerve neuropathy at the carpal tunnel. We believe that a compressive lesion of the median nerve at the carpal tunnel can be present both in patients with no typical symptoms of CTS (including asymptomatic individuals) and in patients in which neurophysiologic studies are negative. SIGNIFICANCE: Further studies separating patients into these groups will allow us to identify the long-term prognosis as well as the ideal therapeutic approach for each of these clinical situations.  相似文献   
1000.
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