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31.
Natural history of parathyroid function and calcium metabolism after kidney transplantation: a single-centre study. 总被引:10,自引:4,他引:6
Pieter Evenepoel Kathleen Claes Dirk Kuypers Bart Maes Bert Bammens Yves Vanrenterghem 《Nephrology, dialysis, transplantation》2004,19(5):1281-1287
BACKGROUND: The natural history of parathyroid function after successful renal transplantation (RT) and the factors predisposing to persistent hyperparathyroidism (HPT) are not well established. A better knowledge of these data may be helpful in the development of algorithms for optimal surveillance and treatment of HPT after successful RT. Our aim was to evaluate the post-transplant natural history of parathyroid function and calcium metabolism in patients with a functional renal graft and to identify risk factors for persistent HPT. METHODS: Charts of 1165 allograft kidney recipients transplanted between 1989 and 2000 were reviewed. Patients with an intact parathyroid hormone (iPTH) level available at the time of transplantation were identified. The charts of the latter patients were checked for a variety of demographic and clinical data, and all determinations of the iPTH concentration available since transplantation were recorded. Serum levels of calcium, phosphorus, alkaline phosphatases and creatinine, concurrently determined, were also registered. RESULTS: After an initial fall, iPTH levels showed a slow but steady decline towards the upper normal limit. The prevalence of persistent HPT, defined as an iPTH level > or =2.5 times the upper normal limit or the need for parathyroidectomy following transplantation, remained stable at approximately 17% up to 4 years after transplantation. Patients with persistent HPT had significantly elevated serum levels of iPTH, calcium and phosphorus at the time of RT, and had spent a longer time on dialysis. Post-transplant iPTH levels correlated significantly with transplant kidney function. CONCLUSION: Kidney transplant recipients with a high iPTH and calcium x phosphate product at the time of transplantation are at risk for persistent HPT especially when renal function is suboptimal. Therapy for persistent HPT, if considered, should be initiated 3 months post-transplantation since further spontaneous improvement of parathyroid function thereafter is limited. 相似文献
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Dr. Hajo Dirk Weitmann Tomas Hendrik Knocke Claudia Waldhäusl Richard Pötter 《Strahlentherapie und Onkologie》2006,182(2):86-95
BACKGROUND: In advanced vaginal recurrences of cervical and endometrial carcinomas therapeutic options are rare because of preceding therapy. PATIENTS AND METHODS: 23 patients developing advanced vaginal recurrences of cervical and endometrial carcinomas were included. 15 patients started with external-beam therapy to the pelvis and eight patients after preceding radiotherapy underwent brachytherapy alone. All patients had ultrasound-guided implantation of transvaginal or transperineal interstitial needles for brachytherapy. Median prescribed total dose was 64 Gy. RESULTS: 18 patients (78%) achieved complete remission. Six patients are alive without tumor and one with tumor after a median follow-up of 64 months. 14 patients died of tumor and two of intercurrent disease. 5-year disease-specific survival and local control rate were 43% and 47%, respectively, in patients with complete remission. Univariate analysis found time to relapse > 2 years, initial diameter < or = 4 cm, initial volume < 15 cm(3), no extension to the pelvic side wall, volume before brachytherapy < 7.5 cm(3), brachytherapy coverage index > 0.8, and prescribed total dose > 64 Gy being positive predictors for local control and survival. CONCLUSION: The use of ultrasound guidance for placement of interstitial needles in template-based brachytherapy of advanced recurrent gynecologic malignancies is a feasible, safe, and cheap method with encouraging results. Today, ultrasound imaging can be also used to some extent for treatment planning which requires further development. Patient- and treatment-related prognostic factors can be defined. 相似文献
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Kirsten Leineweber Dirk B?se Magdalene Vogelsang Michael Haude Raimund Erbel Gerd Heusch 《Journal of the American College of Cardiology》2006,47(5):981-986
OBJECTIVES: We sought to identify soluble vasoconstrictor substances that are released during stent implantation into saphenous vein aortocoronary bypass grafts. BACKGROUND: Atherosclerotic saphenous vein aortocoronary bypass grafts are particularly vulnerable to plaque rupture. Protection devices prevent particulate debris from being embolized. Additional soluble vasoconstrictor substances possibly also contribute to impaired microvascular perfusion. METHODS: Peripheral venous blood (VB) and aspirate (AS) were obtained from 14 patients with a significant stenosis in a saphenous vein graft during stent implantation under protection with a distal balloon occlusion device. In five additional patients, arterial blood (AB) was also taken distal to the stented lesion before intervention. Vasomotor substances in VB, AB, and AS plasma were identified in a bioassay of rat mesenteric arteries with intact (+E) and denuded endothelium (-E). Vasoconstriction was normalized to that induced by potassium chloride depolarization (100%). RESULTS: Venous blood, AB, and AS plasma induced maximum vasoconstriction within six minutes. The AS plasma induced a vasoconstriction of 138 +/- 13% (-E) and 87 +/- 14% (+E); VB, of 70 +/- 14% (-E) and 23 +/- 4% (+E); and AB plasma obtained before intervention, of 49 +/- 9% (-E) and 36 +/- 8% (+E). The vasoconstrictor potency of AS plasma in endothelium-denuded vessels was related to the severity of anginal symptoms, angiographic stenosis severity, plaque volume, and plaque burden as determined by intravascular ultrasound. The AS plasma-induced vasoconstriction was largely attenuated by combined serotonin/5-hydroxytryptamine (5-HT)(2A/2C)- and 5-HT(1A/1B)-receptor blockade and eliminated by additional thromboxane A2 thromboxane-prostanoid (TP)-receptor blockade. CONCLUSIONS: Stent implantation releases, apart from and in addition to particulate debris, soluble vasoconstrictor substances that possibly contribute to impaired microvascular perfusion. 相似文献
37.
Veronique Verhoeven Lieve Peremans Dirk Avonts Paul Van Royen 《The European journal of contraception & reproductive health care》2006,11(3):175-180
INTRODUCTION: We describe the use of emergency contraception (EC) and its association with sociodemographic, contraceptive and behavioural characteristics in a sample of family practice attendants in Belgium. METHODS: The study was part of a large Chlamydia trachomatis (CT) prevalence study in general practice. Sexually active women under 40 who consulted their general practitioner for routine gynaecological care were enrolled in the study. Participants completed a questionnaire on sociodemographic variables, urogenital symptoms, sexual history and sexual behaviour, and delivered a sample for CT testing. Logistic regression analysis was performed to identify determinants of a history of EC use in women in this sample. RESULTS: Of 815 questioned women, 23.5% had ever used EC. EC users were a heterogeneous group with respect to educational level, age and ethnicity. The use of emergency contraception was associated with the level of urbanisation, condom use, not having children yet, young age of first sexual intercourse, having had multiple partners in the past year, a history of unintended pregnancy, and current or previous STI. DISCUSSION: Information on availability and correct use of EC, and on the need for additional testing for STI, are necessary to help primary care attendees to preserve their future reproductive health. 相似文献
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Arnold P. Oranje Dirk Van Gysel Paul G. H. Mulder Paul H. Dieges 《Contact dermatitis》1994,31(5):314-318
IgE-mediated contact urticaria syndrome (CUS) is one of the manifestations of allergy in childhood atopic dermatitis (AD). Allergens such as foods and animal products penetrate the skin easily. They can then cause urticarial reactions in sensitized individuals. A provocation test system for foods, called the skin application food test (SAFT), has been developed. Over more than 5 years, a group of 175 patients with AD was built-up and investigated in a prospective follow-up study with SAFT. SAFT was more frequently positive in AD children aged 6–2 years than in older children. In several children of this population (Group 1), we repeated SAFT within a period of 1 year. In another unrelated group of children (Group 2–1), we compared the results of 'original' SAFT and SAFT using square chambers (Van der Bend) or Silver patches. In the 3rd group (Group 2–2) we compared'original' SAFT with SAFT using big Finn Chambers. The agreement between the tests was high: in Group 1, we observed 88 to 93% concordant scores, and in Group 2, the scores were 96% to 100%. Statistically, the K coefficient ranged from 0.71–0.87 in Group 1, and from 0.83–1.00 in Group 2. SAFT is therefore highly reproducible. Agreement was at least 88% between the scores (the lowest K value observed was at least 0.71). 相似文献
40.
Jie Lian Dirk Müssig Volker Lang 《Europace : European pacing, arrhythmias, and cardiac electrophysiology》2007,9(7):506-513
AIMS: To quantitatively compare the ventricular rate-smoothing (VRS) effects of different ventricular pacing (VP) protocols for atrial fibrillation (AF). METHODS AND RESULTS: Using a recently developed open-source model that can simulate the ventricular response in AF and VP, the performance of fixed-rate pacing and four previously published VRS algorithms were assessed by the mean RR (mRR), the root mean square of successive RR differences (RMSSD), the percentage of ventricular senses (VS%), and the percentage of short RR intervals (sRR%). All pacing protocols cause rate-dependent reduction of RMSSD, VS%, and sRR% with or without shortening of mRR compared to spontaneous AF. Fixed-rate pacing was more sensitive to the intrinsic rate than the VRS algorithms. The performance was generally comparable between different VRS algorithms, although higher mRR and VS% can be achieved at the expense of larger RMSSD and sRR%. CONCLUSION: The effect of VP on ventricular rhythm in AF depends on both intrinsic rate and the aggressiveness of the pacing protocol. Adequate rate control is necessary for effective operation of the VRS algorithm. Choosing VRS algorithm should balance between the beneficial effects of rate regularization and the negative effects of increasing heart rate and percentage of VP. 相似文献