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991.

Objective

We wanted to valuate the mid-term therapeutic results of percutaneous transhepatic balloon angioplasty for portal vein stenosis after liver transplantation.

Materials and Methods

From May 1996 to Feb 2005, 420 patients underwent liver transplantation. Percutaneous transhepatic angioplasty of the portal vein was attempted in six patients. The patients presented with the clinical signs and symptoms of portal venous hypertension or they were identified by surveillance doppler ultrasonography. The preangioplasty and postangioplasty pressure gradients were recorded. The therapeutic results were monitored by the follow up of the clinical symptoms, the laboratory values, CT and ultrasonography.

Results

The overall technical success rate was 100%. The clinical success rate was 83% (5/6). A total of eight sessions of balloon angioplasty were performed in six patients. The mean pressure gradient decreased from 14.5 mmHg to 2.8 mmHg before and after treatment, respectively. The follow up periods ranged from three months to 64 months (mean period; 32 months). Portal venous patency was maintained in all six patients until the final follow up. Combined hepatic venous stenosis was seen in one patient who was treated with stent placement. One patient showed puncture tract bleeding, and this patient was treated with coil embolization of the right portal puncture tract via the left transhepatic portal venous approach.

Conclusion

Percutaneous transhepatic balloon angioplasty is an effective treatment for the portal vein stenosis that occurs after liver transplantation, and our results showed good mid-term patency with using this technique.  相似文献   
992.
Purpose Ischaemic myocardial dysfunction shows different time courses of functional recovery according to the pathophysiological characteristics of the dysfunction. In this study, we investigated the time course of functional recovery according to the preoperative reversibility of perfusion impairment on myocardial single-photon emission computed tomography (SPECT) after revascularisation surgery.Methods Forty-eight patients (42 men and 6 women; mean age 59±9 years) who underwent revascularisation surgery were included in the study. 201Tl rest/dipyridamole stress 99mTc-sestamibi gated SPECT was performed 10±8 days before (preoperative), 105±13 days after (early follow-up) and 497±66 days after (late follow-up) surgery. Using a 20-segment model, segmental perfusion and thickening were quantified with automatic software. As an indicator of the reversibility of perfusion impairment, a reversibility score (RevS) was defined as a measure of rest minus stress perfusion values. Segmental dysfunction and functional recovery were defined from quantified thickening values. Function-recovered segments were divided into early recovery and late recovery groups, and preoperative perfusion status was compared in these groups. Function-recovered segments were also re-classified into high-RevS and low-RevS groups according to the preoperative RevS, and the time courses of functional recovery were investigated in each group.Results A total of 502 segments were included in the analysis and 263 were finally classified as function-recovered segments. Of these, 172 were in the early recovery and 91 in the late recovery group. In terms of preoperative perfusion status, RevS was 8.9±10.8 in the early recovery group and 5.4±11.0 in the late recovery group (P=0.01). When all 502 segments were classified by RevS, no difference in the proportion of final function recovery was observed between the high-RevS and the low-RevS group (54% vs 51%). However, the proportion of early recovery was higher in the high-RevS group (73%) than in the low-RevS group (57%) (P=0.01).Conclusion Ischaemic dysfunctional myocardium with reversible perfusion impairment tends to recover function earlier after revascularisation surgery than myocardium with a persistent decrease in perfusion.  相似文献   
993.
994.
BACKGROUND: After serial passages in monolayer, chondrocytes dedifferentiate into a fibroblast-like phenotype. Our objective was to determine if culture in alginate affects the phenotype of dedifferentiated human nasal septal chondrocytes. STUDY DESIGN: Human nasal septal chondrocytes were seeded at low density and passaged in monolayer culture. At passages (P) 1, 2, and 3 a portion of cells were cultured in alginate. Collagen, glycosaminoglycan (GAG), and DNA production were assessed. RESULTS: Chondrocytes in alginate proliferated less yet produced higher levels of GAG and collagen than those in monolayer culture. Alginate encapsulated P1 chondrocytes stained strongly for GAG and collagen type II, and minimally for collagen type I. Monolayer cells at P0 and P1 stained positively for collagen type II. All monolayer passages stained positive for collagen type I with minimal GAG staining. CONCLUSIONS: Compared with monolayer culture, alginate stimulates deposition of GAG and collagen type II, and supports the chondrocyte phenotype through P1, but does not promote redifferentiation.  相似文献   
995.
Park K  Ku JH  Kim SW  Paick JS 《BJU international》2005,95(3):366-370
OBJECTIVE: To assess the clinical efficacy of sildenafil and the potential predictors of poor response to sildenafil in elderly patients with erectile dysfunction (ED). PATIENTS AND METHODS: The study included 162 patients (aged > or = 60 years) treated with sildenafil for at least 8 weeks; all patients were evaluated with a history, physical examination, measurement of total testosterone and a pharmacological erection test. Sexual function before and 8 weeks after treatment was assessed using the self-administered International Index of Erectile Function (IIEF). Treatment was considered successful when the patient attained a higher grade on the erectile function (EF) domain score, and an affirmative response to the overall assessment question. Factors influencing treatment outcome were evaluated by univariate and multivariate statistical analysis. RESULTS: The overall efficacy with sildenafil was 47% (76/162). On univariate analysis, uncontrolled diabetes, current smoking, hypogonadism (<3 microg/L testosterone) and low pretreatment EF domain score (<17) were selected as predictors of a poor response. On multivariate logistic regression, a low pretreatment EF domain score was the strongest independent prognostic factor for a poor response (odds ratio 2.25, 95% confidence interval, 1.45-7.33), and this was followed by hypogonadism (1.89, 1.12-3.16) and current smoking (1.34, 1.04-3.52). CONCLUSION: In a real clinical setting, sildenafil was effective for about half of the elderly men. The baseline EF domain score, hypogonadism and current smoking were significantly associated with failure of sildenafil. These results suggest that modifying reversible risk factors, e.g. stopping smoking and replacing testosterone, would be beneficial in augmenting the efficacy of sildenafil in elderly men.  相似文献   
996.
OBJECTIVE(S): We have previously shown that type II endoleak size is a predictor of aneurysm growth after aortic endografting. To better understand this observation, we investigated the influence of endoleak size on pressure transmitted to the aneurysm wall and its distribution within the aneurysm sac. METHODS: In an ex vivo model, an artificial aneurysm sac was incorporated within a mock circulation comprised of rubber tubing and a pulsatile pump. Three strain-gauge pressure transducers were placed in the aneurysm wall at different locations, including the site of maximum aneurysm diameter. The aneurysm was filled with either human aneurysm thrombus or dough that mimicked thrombus and simulated type II endoleaks of varying volumes (1 to 10 mL) were created. Aneurysm wall pressure (AWP) measurements were recorded at mean arterial pressures (MAPs) of 60, 80, and 100 mm Hg. Correlation coefficients ( r ) and analysis of variance were used to assess the relationship between endoleak volume and AWP. RESULTS: Increasing endoleak volume '3 cm 3 resulted in proportionally increased AWP at all levels of MAP and at all sites, with highest pressures recorded at the site of the maximum aneurysm diameter (r = 0.83 when MAP = 100 mm Hg; r = 0.85 when MAP = 80 mm Hg; r = 0.88 when MAP = 60 mm Hg; P < .001). AWP plateaued when the endoleak volume was >3 cm 3 . Pressure distribution within the sac was not uniform. Although the difference was within +/-10%, statistically significant higher AWPs were observed at the site of maximum aneurysm diameter (P <.001). AWP also correlated with MAP. CONCLUSIONS: Increasing type II endoleak volume results in proportionally higher AWP, which is greatest at the site of maximum aneurysm diameter. This study confirms the clinical observation that type II endoleak volume and MAP may be important predictors of aneurysm expansion. CLINICAL RELEVANCE: Our experimental model of a type II endoleak revealed that endoleak size is a significant factor that influences the magnitude of pressure transmission into the aneurysm wall. Increasing volume of the endoleak nidus was associated with proportionally higher aneurysm sac pressures. This mechanism may, in fact, account for the increased risk of aneurysm expansion observed in our clinical experience, thereby suggesting the need for more aggressive surveillance and possibly earlier intervention for patients with larger endoleaks.  相似文献   
997.
Yang SS  Tsai YC  Wu CC  Liu SP  Wang CC 《The Journal of urology》2005,173(4):1361-1363
PURPOSE: We report a prospective randomized study comparing the effects of highly potent and moderately potent topical steroids in treating pediatric phimosis. MATERIALS AND METHODS: A total of 70 boys 1 to 12 years old with phimosis were randomly assigned to receive topical application of either betamethasone valerate 0.06% (a highly potent steroid) or clobetasone butyrate 0.05% (a moderately potent steroid). Parents of the boys were instructed to retract the foreskin gently without causing pain, and to apply the topical steroids over the stenotic opening of the prepuce twice daily for 4 weeks, then for another 4 weeks if no improvement was achieved. Retractibility of the prepuce was graded from 0 to 5. Response to treatment was arbitrarily defined as improvement in the retractibility score of more than 2 points. RESULTS: Mean treatment and followup periods were 4.3 and 19.1 weeks, respectively. The response rates in boys treated with betamethasone valerate and clobetasone butyrate were 81.3% and 77.4%, respectively (p = 0.63). Mean retractibility score decreased from 3.9 +/- 1.0 to 1.7 +/- 1.1, and 4.2 +/- 1.0 to 1.9 +/- 1.0 in the betamethasone and clobetasone groups, respectively. Both steroids were effective in all age groups. Pretreatment retractibility score did not affect treatment outcomes. No adverse effect was encountered. CONCLUSIONS: Highly potent and moderately potent topical steroids are of comparable effectiveness in treating phimosis. A less potent steroid may be considered first to decrease the risk of the potential adverse effects.  相似文献   
998.
999.
There is growing evidence that soy isoflavones exert hormonal and antioxidant effects in postmenopausal women. In the present study, 12 postmenopausal Korean women with diabetic retinopathy consumed 2 g of genistein combined polysaccharides (GCP), containing 120 mg of genistein and 57 mg of daidzein, daily for 12 weeks. Blood was collected prior to and after 12 weeks of GCP supplementation for analysis of fasting blood glucose, insulin, lipid profiles, sex hormone-binding globulin (SHBG), estradiol, testosterone, free testosterone, and osteocalcin and activities of glutathione peroxidase (GSH-Px), catalase, and paraoxonase. After GCP supplementation, blood glucose, insulin, total cholesterol, triglyceride, high-density lipoprotein, and low-density lipoprotein cholesterols did not change significantly. However, there were significant increases in SHBG (P < .05) and testosterone (P < .05) and a decrease in estradiol (P < .01). Free testosterone levels were not significantly affected by GCP supplementation. After supplementation, osteocalcin decreased, but the difference was not statistically significant. Although activities of catalase and paraoxonase were unchanged, GSH-Px activity (P < .01) was increased significantly. These findings suggest that GCP supplementation may change the levels of some hormones and improve antioxidant status in postmenopausal Korean women with diabetic retinopathy.  相似文献   
1000.
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