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BACKGROUND: Adequate care of a hemodialysis patient requires constant attention to the need to maintain vascular access (VA) patency. VA complications are the main cause of hospitalization in hemodialysis patients. The native arteriovenous fistula (NAVF), synthetic arteriovenous grafts fistula (GAVF) and silastic cuffed central venous catheters (CVCs) are used for permanent vascular access (PVA). CVCs are primary the method of choice for temporary access. But using this access modality is increasing more and more for PVA in elderly hemodialysis patients and when other PVA is not possible. The primary aim of this study is to investigate survivals and complications of the CVCs used for long-term VA. METHODS: We prospectively looked at 92 CVCs (Medcomp Ash Split Cath, 14 FR x 28 cm (Little, M.A.; O'Riordan, A.; Lucey, B.; Farrell, M.; Lee, M.; Conlon, P.J.; Walshe, J.J. A prospective study of complications associated with cuffed, tunnelled hemodialysis catheters. Nephrol. Dial. Transplant. 2001, 16 (11), 2194-2200) with Dacron cuff) inserted in 85 (50 females, 35 males) chronic hemodialysis patients (the mean age: 56.6 +/- 14.1 years) from July 1999 to January 2002. The overall survival and complications were followed up. Furthermore, the patients were evaluated for demographic and clinical characteristics. Data were analysed by chi-square, Wilcoxon rank and Kaplan-Meier survival tests. RESULTS: The median duration of CVC survival was 289 days (range: 10-720). Eleven (11.9%) CVCs were removed due to complications. In 79 (92.9%) patients, 1, in 5 (5.8%) patients, 2 and in 1 patient, 3 CVCs were inserted. Of the 85 patients, 56 have CVCs functioning. In addition, 27 (31.76%) patients have CVCs functioning for over 12 months, 17 (20%) patients have CVCs functioning for 6 months. The total incidence of CVC related infections was 0.82 episodes/1000 catheter days. Besides, thrombosis was occurred in 10 (10.8%) CVCs. The most frequent indications for CVC removal were patient death (69.4%), thrombosis (16.6%) and CVC-related infections (13.8%). CONCLUSIONS: CVCs are primarily used for temporary access. But this study indicates that CVC may be a very useful alternative permanent vascular access for hemodialysis patients when other forms of vascular access are not available.  相似文献   
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Our objective was to describe MR imaging findings of liver lesions in human fascioliasis. The MR imaging of the liver was performed in 29 patients with fascioliasis. Seventeen patients were women and 12 were men, with a mean age of 47.5 years (age range 17–75 years). Hepatic lesions were grouped into five types based on their signal characteristics. Three patients had normal imaging findings. One or more lesions were observed in the other 26 patients. The lesion types and the frequency of appearances were as follows: hyperintensity of the liver capsule on T2-weighted images (n=16, 55.2%); ill-defined slightly hyperintense areas on T2-weighted images (n=18, 62.1%); lesions which were hypointense on T1-weighted and hyperintense on T2-weighted images (n=10, 34.5%); hypointense on T1-weighted images and centrally hypo- or hyperintense, surrounded by peripherally less hyperintense area on T2-weighted images (n=4, 13.8%); and hypointense foci or ill-defined hypointense areas on T1- and T2-weighted images (n=10, 34.5%). We describe the MR imaging features of the disease. Our findings may help the differential diagnosis in which fascioliasis should be added to the list. Electronic Publication  相似文献   
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It is generally accepted that the phospholipase-A2-cyclooxygenase-prostanoids-cascade mediates spinal sensitization and hyperalgesia. However, some observations are not in line with this hypothesis. The aim of the present work was to investigate whether different components of this cascade exhibit nociceptive or antinociceptive effects in the rat formalin test. Intrathecal (i.th.) injection of prostaglandin E2 (PGE2) induced a dose-dependent antinociceptive effect on the formalin-induced nociception. Furthermore, thimerosal, which inhibits the reacylation of arachidonic acid thereby enhancing arachidonic acid levels, had an antinociceptive effect rather than the expected pronociceptive effect when given i.th. While the phospholipase A2 inhibitor methyl arachidonyl fluorophosphonate (MAFP; i.th.) had a significant antinociceptive effect, its analogue palmitoyl trifluoromethyl ketone (PTFMK; i.th.) had no significant effect on the formalin-induced nociception. However, MAFP, but not PTFMK, showed a cannabinoid CB1 agonistic effect as shown by the inhibition of electrically evoked contractions of the vas deferens isolated from CB1 wild-type mice but not of that from CB1 knockout mice. The antinociceptive effect of MAFP was completely reversed by the CB1 receptor antagonist AM-251 (i.th.), thus attributing such effect to its CB1 agonistic effect. Moreover, the antinociceptive effect of the cyclooxygenase inhibitor, flurbiprofen (i.th.) was reversed by the co-administration of AM-251, but not by PGE2. Finally. the combination of phenylmethylsulfonyl fluoride (PMSF; intraperitoneal), which inhibits the degradation of anandamide through the inhibition of fatty acid amidohydrolase, with thimerosal (i.th.) produced a profound CB1-dependent antinociception. The present results show that endocannabinoids play a major role in mediating flurbiprofen-induced antinociception at the spinal level.  相似文献   
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With color Doppler imaging, we attempted to determine whether glaucoma patients with asymmetric visual field losses had evidence of asymmetric blood flow velocities in the central retinal artery despite similar intraocular pressure (IOP) curves in both eyes. We found that eyes with more severe visual field damage had an increased local resistance to blood flow in the central retinal artery. Thus vascular factors might have important roles in the pathogenesis of primary open-angle glaucoma.  相似文献   
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Objective  

To evaluate prospectively the rate of postoperative failure of McCall culdoplasty and the presence of a history of vaginal delivery of macrosomic infants as risk factors in patients with stage III or symptomatic stage II apical prolapse without any other pelvic floor defects.  相似文献   
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