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PURPOSE: In children with locally advanced or recurrent malignant tumours, prognosis can be improved by regional deep hyperthermia (RHT) in combination with platin-based chemotherapy. However, because of the increasing number of patients that achieve long-time remission with this therapy, it is necessary to evaluate long-term sequelae of thermochemotherapy. During the years 1993-2004 one has observed avascular osteonecrosis (AON) of the femoral head after RHT in seven children with pelvic germ cell tumours or rhabdomyosarcomas. METHODS: Although AON may develop in patients with malignancies treated with chemo- or radiotherapy alone, RHT might nevertheless contribute to the occurrence of AON. In order to determine potential risk factors for AON after RHT, this study analysed the relationship of AON to the patient's age, medical history and treatment parameters such as thermal dose equivalent and power output. RESULTS AND CONCLUSIONS: In the present study AON was associated with young age as well as intensity of hyperthermia indicated by high power levels that exceed 20 W per kg body weight and/or application of eight or more heat sessions as well as additional radiotherapy. Based on this observation, it was assumed that an optimized three dimensional thermal field modelling may be helpful to avoid hazardous temperatures in the femoral heads during RHT treatment and to reduce AON of the femoral heads.  相似文献   
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A prospective study of 17 cases of microsurgical reversal of tubal sterilization by a combined approach of laparoscopy and minilaparotomy was performed. Inclusion criteria included age less than 43; weight less than ideal body weight plus 20%; documentation of ovulation; 2 cm of proximal oviduct on hysterosalpingography; and a normal semen analysis or postcoital test. A comparison group of the 5 cases of sterilization reversal performed by a standard inpatient technique during the same period was analyzed. The study technique was performed on an outpatient basis in 15 of the 17 cases, 12 patients (71%) conceived 13 intrauterine pregnancies, one ectopic pregnancy occurred, and total patient costs and time until return to work were significantly less with the study versus standard technique.  相似文献   
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PURPOSE: To analyze the effectiveness of surgery and chemotherapy with or without radiotherapy in the management of limited small cell lung cancer (LSCLC) in stages I and II. PATIENTS AND METHODS: 39 patients (median age 62 years) with LSCLC in stages pT1 or pT2 and pN0 or pN1 (stages IA-IIB) who had a tumor resection and systematic lymph node dissection were reviewed retrospectively. The median follow-up period was 29 months. 35 patients (90%) received a median of four cycles of a platinum-containing chemotherapy postoperatively. 16 patients (41%) received an adjuvant thoracic radiotherapy (TRT, median 50 Gy); 21 patients (54%) received a prophylactic cranial irradiation (PCI, median 30 Gy). RESULTS: The median overall survival for all patients was 47 months, resulting in actuarial 1-, 3-, and 5-year survival rates of 97%, 58%, and 49%, respectively. Distant metastases were found in 13 patients (33%) after a median of 16 months. Patients who received an adjuvant TRT showed a trend toward improved thoracic recurrence-free survival (p = 0.06) and improved overall survival (p = 0.07) compared to those treated with surgery and chemotherapy only. Brain metastasis-free survival (p = 0.01) and overall survival (p = 0.01) were improved significantly in patients who received a PCI. CONCLUSION: Surgical tumor resection may be considered for carefully selected patients. Adjuvant chemotherapy and PCI are recommended for all patients. Adjuvant TRT is currently used in patients with positive lymph nodes (pN1), because the probability of a subclinical involvement of the mediastinal lymphatic system appears to be increased in these patients.  相似文献   
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Re-epithelialization of cutaneous wounds is a coordinated process of proliferation and migration of keratinocytes at the wound edge. The study objective was to identify the differences in epidermal morphology, keratinocyte proliferation and matrix molecules (laminin 1, laminin 5, type IV collagen) and their specific integrin (α3, α6) expression in biopsies of meshed split thickness grafted and chronic wounds. The mean mitotic index of keratinocytes (ratio of cell cycle associated antigen Ki-67 expressing keratinocytes to basal keratinocytes) was highest in chronic wounds (38.7%) compared to acute wounds (22.25%, range 5.7% to 54%). The mean thickness of the hyper-proliferative epithelium at the wound edge of chronic wounds was 0.69 mm compared to 0.15 mm at the wound margin of split thickness grafted wounds. Both chronic wounds and skin grafted wounds exhibited strong laminin 5 immunoreactivity at the basal side of the epithelium, which extended under the most forward keratinocytes. Laminin 1 and type IV collagen immunoreactivity did not extend to the wound margin in either skin grafted or chronic wounds. In both transplanted skin and chronic wounds, the integrin sub-units α3 and α6 exhibited a strong pericellular immunoreactivity on the leading keratinocytes of the wound margin. Our data demonstrates that the proliferation of keratinocytes and the expression of associated integrins are not impaired in chronic wounds. Presented at the 33rd Congress of the Association of German Plastic Surgeons, Germany, 18–21 September, 2002.  相似文献   
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BACKGROUND: Dyslipidaemia, inflammation and oxidative stress are prominent risk factors that potentially cause vascular disease in haemodialysis patients. Dialysis modalities affect uraemic dyslipidaemia, possibly by modifying oxidative stress, but the effects of dialyser flux and membrane material on atherogenic remnant particles and oxidized low-density lipoproteins (LDL) are unknown. METHODS: We performed a randomized crossover study in 36 patients on haemodialysis to analyse the effect of dialyser flux and membrane material on plasma lipids, apolipoproteins and markers of inflammation and oxidative stress. Stable patients on low-flux dialysis with polysulphone for >/=6 weeks were assigned to high-flux polysulphone or high-flux modified cellulose with similar dialyser surface area and permeability characteristics and crossed over twice every 6 weeks. RESULTS: Thirty patients completed the study per protocol. Treatments with high-flux polysulphone and modified cellulose lowered serum triglyceride (by 20% and 10%, respectively; P<0.05) and remnant-like particle cholesterol by 32% (P<0.001) and 11% (NS) after the first 6 weeks of treatment. Oxidized LDL decreased significantly with high-flux polysulphone, but not with modified cellulose. Apolipoproteins CII and CIII were reduced, whereas the ratio CII/CIII was increased (all P<0.05). Acute-phase proteins and LDL and high-density lipoprotein cholesterol remained unaffected. CONCLUSIONS: This randomized crossover study demonstrates a potent effect of high-flux haemodialysis on uraemic dyslipidaemia. Polysulphone membrane material showed superiority on oxidatively modified LDL, an indicator of oxidative stress in haemodialysis patients.  相似文献   
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Cardiac catheterisations in newborns and infants are being performed routinely in increasing numbers for diagnostic and therapeutic purposes. Rarely, the femoral artery or the iliac artery will be completely occluded after such a procedure, and growth retardation of the lower extremity can result. We report on a case of iliofemoral artery occlusion following cardiac catheterisation in an infant. Twelve years later, a difference of 5.5 cm in leg length was noted, as well as a difference in shoe size and intermittent claudication. Following operative reconstruction, the child’s leg pain ceased. Two years after surgery, differences in leg lengths and shoe sizes are no longer significant. Vascular complications should not be underestimated despite the juvenile potential for collateral vessels. Even in the absence of signs of ischaemia, these complications necessitate further investigation and adequate treatment in due course.  相似文献   
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Quantification of oxidative DNA modifications in mitochondria   总被引:2,自引:0,他引:2  
Specific repair endonucleases were used to quantify oxidativemodifications in mitochondrial DNA (mtDNA) from rat liver andfrom porcine liver and kidney by means of a relaxation assay.In rat liver mitochondria the number of modifications sensitiveto formamidopyrimidine-DNA glycosylase (FPG protein), whichinclude 8-hydroxyguanine (8-oxo-7, 8-dihydro-guanine) residues,was only 0.8±0.2 per 105 base pairs (bp). Even lowervalues were observed in porcine kidney (0.5±0.3 per 105bp) and liver (0.4±0.2 per 105 bp). The numbers of sitesof base loss (AP sites) sensitive to T4 endonuclease V and of5,6-dihydropyrimidines sensitive to endonuclease III were lessthan 0.2 per 105 bp in all cases. The data provide evidencethat the steady-state levels of oxidative mtDNA modificationsare low under physiological conditions, either because reactiveoxygen species generated in the mitochondria are instantly inactivatedor because of efficient DNA repair processes inside mitochondria.  相似文献   
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