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951.
BACKGROUND: Because subintimal angioplasty (SA) is a technique that can achieve recanalization of long arterial occlusions, it is considered an alternative to lower limb bypass operations. The aim of this prospective study was to identify the risk factors that affect patency of SA in patients suffering from critical limb ischemia (CLI). METHODS AND RESULTS: 51 consecutive infrainguinal SA were done in 46 patients suffered from CLI. The patients were followed-up with regular duplex scans up to 12 months post-intervention. Sex, atherosclerosis risk factors, and some technical details of the procedure (number of patent run-off vessels after the procedure, length and re-entry point of angioplasty) were examined as potential risk factors of patency, using survival analysis statistical techniques. The overall patency rate at 12 months post-intervention was 50%. According to Cox-regression analysis, the factors that affect patency were the number of run-off vessels and the length of occlusion. Patients with two or three run-off vessels had a hazard of occlusion of 0.30 (P = .027) compared to those who had one run-off vessel. The 12-months patency in patients with more than one run-off vessels was 81% vs. 25% in patients with one run-off vessel. Regarding the length of angioplasty, the hazard of reocclusion was 1.02 for every centimeter of occlusion (P = .049). CONCLUSIONS: The number of patent run-off crural vessels after the angioplasty and the length of occlusion are significant risk factors for reocclusion of infrainguinal SA in patients with CLI. Trying to recanalize more than one run-off vessels could raise the SA patency.  相似文献   
952.
BACKGROUND: Several authors have demonstrated the existence and implications of re-innervation in the transplanted heart. Our aim was to study this phenomenon using 3 different techniques and to analyze the correlation among them. METHODS: The study population consisted of 55 patients who had undergone heart transplantation 0.5 to 160 months earlier. We used a control group of 10 healthy individuals for comparison. To detect re-innervation, we used 1) planar and single photon emission computed tomography (SPECT) scintigraphic imaging of cardiac sympathetic activity with 123I-metaiodobenzylguanidine (MIBG), 2) analysis of heart-rate variability based on 24-hour Holter recordings; and 3) immunohistochemical study of endomyocardial biopsy specimens with anti-S100 antibody. RESULTS: The SPECT images showed evidence of sympathetic re-innervation in 17 patients (31%), predominantly in the anterior and in the septal regions of the left ventricle. Sympathetic activity increased during the post-transplant time course (r = 0.32; p = 0.017), although it did not reach normal values. We found a correlation between the low-frequency component of heart-rate variability (a marker of sympathetic activity) and the degree of MIBG uptake according to scintigraphy (r = 0.32; p = 0.015). Immunostaining study demonstrated the existence of nerve fibers in 36 patients (65%) who had greater values of heart-rate variability parameters reflecting parasympathetic activity. CONCLUSIONS: The 3 techniques evidenced re-innervation after heart transplantation. A correlation exists between sympathetic activity detected using MIBG scintigraphy and analysis of heart-rate variability. Patients in whom endomyocardial biopsy specimen reveals the presence of nerve fibers show more parasympathetic activity in the heart-rate variability analysis.  相似文献   
953.
1. Concentrations of albumin and alpha-1-acid glycoprotein (AGP) in human cervical mucus have been measured by a radial immunodiffusion technique. 2. The cervical mucus samples were obtained from women on combined oral contraceptives (Group A) and from women not taking this medication (Group B). In group A the mean level of albumin was 75.6 (range 22-198) mg l-1 and for AGP 6.5 (range 3-12) mg l-1. In group B the mean level of albumin was 72.9 (range 22-148) mg l-1 and for AGP 6.6 (range 3-14) mg l-1. 3. The levels of albumin and AGP in cervical mucus were less than 1% of the concentration in serum and were not affected by combined oral contraceptives. 4. The clinical and toxicological consequences of these observations, in terms of the disposition of drugs and other chemicals in the female genital tract, await elucidation.  相似文献   
954.
955.
Six patients with a stone disease and/or ureteropelvic junction obstruction in a horseshoe kidney underwent percutaneous surgery. No major complications were observed and only 1 patient presented residual fragments in the lower calyx 3 months after treatment. The special features of the use of percutaneous nephrolithotomy and endopyelotomy for this anomaly are described.  相似文献   
956.
The long-term effects of cytomegalovirus (CMV) infections on kidney allografts are unknown. We examined the impact of persistent intragraft CMV infection on long-term kidney allograft function and survival. CMV was diagnosed in 82/172 renal transplant recipients by antigenemia test and viral cultures. Biopsies from 48 of 82 patients taken after CMV infection and from 15 patients with no previous CMV infection detected were available for the immunohistochemical demonstration of CMV antigens and DNA hybridization in situ. Five-year follow-up data from these 63 patients were analysed. In 17 patients, CMV antigens and/or DNA persisted in the biopsy >2 months after the last positive finding in blood or urine. Patients with persistent intragraft CMV had reduced graft survival (P = 0.041) and Cox regression analysis showed persistent CMV as a risk factor for reduced graft survival (RR: 3.5). Recipients with persistent intragraft CMV had reduced creatinine clearance 1 and 2 years after transplantation (P = 0.007) and in multivariate logistic regression analyses including several potential pre- and posttransplant risk factors, persistent CMV was an independent risk factor for lower clearance at 1 and 2 years (OR: 4.4 and 4.9). Our novel findings show that persistent intragraft CMV infection was associated with reduced kidney allograft function and survival.  相似文献   
957.
The recent emergence and spread of dengue hemorrhagic fever in the Americas have been a major source of concern. Efforts to control this disease are dependent on understanding the pathogenicity of dengue viruses and their transmission dynamics. Pathogenicity studies have been hampered by the lack ofin vitroorin vivomodels of severe dengue disease. Alternatively, molecular epidemiologic studies which associate certain dengue virus genetic types with severe dengue outbreaks may point to strains with increased pathogenicity. The comparison of nucleotide sequences (240 bp) from the E/NS1 gene region of the dengue virus genome has been shown to reflect evolutionary relationships and geographic origins of dengue virus strains. This approach was used to demonstrate an association between the introduction of two distinct genotypes of dengue type 2 virus and the appearance of dengue hemorrhagic fever in the Americas. Phylogenetic analyses suggest that these genotypes originated in Southeast Asia and that they displaced the native, American genotype in at least four countries. Vaccination and other control efforts should therefore be directed at decreasing the transmission of these “virulent” genotypes.  相似文献   
958.
A questionnaire about assistive devices for lift and transfer was distributed to all individuals evaluated at the Solberga Project outpatient service unit, a regional centre for long-term follow-up of severely brain injured persons in the Greater Stockholm area. The target group was 60 severely brain injured adults, of whom 57 (30 women and 27 men) answered a questionnaire created by one of the authors. The causes of injury in the study population were trauma (n = 27), cerebrovascular accident (n = 19), anoxia (n = 10) and other (n = 1). Thirty-two persons were quadriplegic after the injury and 21 were hemiplegic. More than half (33/57) reported problems with all five defined lift and transfer situations. Most (42/44) reported problems getting in and out of their wheelchairs. Technical aids were seldom used; 24 persons did not use any aids at all. The most commonly used aid was an adjustable bed. Most of the technical aids were used when the individual also had personal assistance. The persons who managed lift and transfer by themselves used few aids. It is reasonable to assume that severely brain injured individuals would be involved in more activities if they used technical aids more readily.  相似文献   
959.
The hardness and frequent recurrence of cystine stones represent a special challenge for the urologist. Fifteen cystinuric patients were treated in our department and followed over a mean period of 30 months. Most patients had a previous history of open surgery (1.5 pyelolithotomy/patient). Diagnosis of cystinuria was confirmed by metabolic studies and stone analysis. Over the follow-up period recurrence was observed in 23 instances in 11 patients thus leading to 38 stone treatments on 74 cystine stones. Stone size was less than 10 mm: 35 (47%); 10-20 mm: 21 (28%); 20-30 mm: 14 (19%); 30 mm: 4 (staghorn stones). A percutaneous approach was used in 9 cases as monotherapy (55% success) and in association with ESWL in 10 cases (50% success). ESWL was employed 18 times as monotherapy (39% success). Medical treatment included high fluid intake, alkalinisation and thiola in 6 patients. In conclusion, results obtained are poor in terms of stone clearance when compared to non-cystine stones. Recurrence rate is very high. Instrumental treatment should not be used excessively and is only indicated in symptomatic stones or refractory to intensive medical therapy.  相似文献   
960.
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