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51.
Neurosurgical Review - Exposure of the anterior skull base is challenging due to strategic structures. The interhemispheric approach (IHA) has turned out to be a feasible technique. We report our...  相似文献   
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53.
BackgroundBreast cancer in young women is associated with unfavourable tumour biology and is the main cause of death in this group. Conditional survival analysis estimates survival rates under the pre-condition of already having survived a certain time.ObjectivesTo describe conditional disease-free and overall survival of female breast cancer patients according to clinical subtypes and age.MethodsThis study analyses information from 1,858 breast cancer patients aged between 21 and 54 years, who were taking part in a post-therapeutic rehab programme (time between diagnosis and rehab start: maximum 24, median 11 months). Mean follow-up time was 3.6 years. We describe biological, clinical and pathological features in regard to different age groups (<40 and ≥40 years) and report conditional 5-year survival rates for overall and disease-free survival, and Cox proportional hazard models.ResultsVery young and young patients differed in regard to hormone receptor negativity, tumour grade, lymphovascular invasion, and molecular subtypes. Young women bore triple-negative and HER2-like disease more frequently. Conditional 5-year overall survival did not differ substantially between women <40 and 40–54 years of age (95 vs. 96%). It was highest for women with cancer of the luminal A subtype (98%) and lowest for the triple-negative subtype (91%). Lymphangiosis was a significant predictor of death. Results for disease-free survival were comparable.ConclusionsConditional 5-year overall survival after non-metastatic breast cancer was as high as 95.5%, and disease-free survival was 85.2%. When controlling for time between diagnosis and rehab start, molecular subtypes influenced overall and disease-free survival prospects. When additionally controlling for clinical characteristics, this effect only remained stable for disease-free survival.  相似文献   
54.
Recently we reported that perfusion of hippocampal slices with epidermal growth factor (EGF) lead to enhancement of potentiated responses after tetanic stimulation. In the present study we report that basic fibroblast growth factor (FGF) can also lead to an enhancement of potentiated responses. FGF is a mitogen for several cell types and exhibits neurotrophic effects on neurons of the central nervous system (CNS). Rat hippocampal slices were perfused with FGF at a concentration of 10-9 M. During extra- and intracellular recordings in the CA1-region, the addition of FGF to the perfusing medium produced no change in evoked responses if single pulse or paired pulse stimulation was used. Furthermore FGF had no influence on the resting membrane potential and input resistance. However, after tetanic stimulation, FGF-treated slices showed an increase in the magnitude of potentiation compared to control slices. Taken together with the EGF data these results support the hypothesis that growth factors like FGF with neurotrophic potential on CNS-neurons can influence synaptic efficacy. Furthermore these results show that factors which are able to modulate developmental plasticity and regenerative plasticity can also modulate synaptic plasticity.  相似文献   
55.
The European Laryngological Society is proposing a classification of different laryngeal endoscopic cordectomies in order to ensure better definitions of postoperative results. We chose to keep the word “cordectomy” even for partial resections because it is the term most often used in the surgical literature. The classification comprises eight types of cordectomies: a subepithelial cordectomy (type I), which is resection of the epithelium; a subligamental cordectomy (type II), which is a resection of the epithelium, Reinke’s space and vocal ligament; transmuscular cordectomy (type III), which proceeds through the vocalis muscle; total cordectomy (type IV); extended cordectomy, which encompasses the contralateral vocal fold and the anterior commissure (type Va); extended cordectomy, which includes the arytenoid (type Vb); extended cordectomy, which encompasses the subglottis (type Vc); and extended cordectomy, which includes the ventricle (type Vd). Indications for performing those cordectomies may vary from surgeon to surgeon. The operations are classified according to the surgical approach used and the degree of resection in order to facilitate use of the classification in daily practice. Each surgical procedure ensures that a specimen is available for histopathological examination. Received: 29 December 1998 / Accepted: 2 July 1999  相似文献   
56.
Tumors of the scapula are an unusual clinical challenge. Partial or complete resection of the scapula, with its attached musculoaponeurotic tissue, is a seldom used technique for the treatment of primary bone and soft tissue tumors, as well as selected metastatic involvement of the scapula. Scapulectomy may allow wide margins of resection without amputation. The purpose of this study is to review our recent experience with scapulectomy. This study describes the recent experience with scapulectomy by the Section of Surgical Oncology and the Department of Orthopedics at Louisiana State Medical Center (New Orleans, LA). Between 1994 and 1998, 12 patients (between 16 and 79 years of age) underwent a resection of the scapula. Eleven of these patients had soft tissue tumors; one had a metastasis from a thyroid carcinoma. Six of these patients underwent a scapulectomy as a primary treatment, five for recurrence. Six patients also received postoperative radiation and/or chemotherapy. The follow-up ranged from 6 months to 4 years. There was no mortality or wound infection associated with scapulectomy. All patients had normal hand and wrist function after surgery. Three distant recurrences occurred, with no local or regional failures encountered during the follow-up period. Scapulectomy can result in excellent local tumor control. Whereas some loss of active shoulder motion may occur, hand, wrist and elbow function is preserved. Although maintenance of shoulder function should not take precedence over adequacy of resection, scapulectomy remains an excellent procedure for malignant disease that preserves hand, wrist, and elbow function.  相似文献   
57.
BACKGROUND: Although in several epidemiological studies exposure to diesel motor emissions (DME) shows an elevated lung cancer risk, it is still controversial whether DME is a human carcinogen. METHODS: In a pooled analysis of two case-control studies on lung cancer in Germany a total of 3498 male cases with histologically or cytologically ascertained lung cancer and 3541 male population controls were included. Information about lifelong occupational and smoking history was obtained by questionnaire. Drivers of lorries, buses, taxies, diesel locomotives and forklift trucks, bulldozers, graders, excavators, and tractors, were considered as exposed to DME and their cumulative exposure was estimated. All odds ratios were adjusted for smoking and asbestos exposure. RESULTS: The evaluation of lung cancer risk for all jobs with DME-exposure combined showed an odds ratio of OR=1.43 (95%-CI: 1.23-1.67). Most pronounced was the increase in lung cancer risk in heavy equipment operators (OR=2. 31 95%-CI: 1.44-3.70). The risk of tractor drivers increased with length of employment and reached statistical significance for exposures longer than 30 years (OR=6.81, 95%-CI: 1.17-39.51). The group of professional drivers (e.g., trucks, buses, and taxies), showed an increased risk only in West Germany (OR=1.44, 95%-CI: 1. 18-1.76), but not in East Germany (OR=0.83, 95%-CI: 0.60-1.14). DME-exposure in other traffic related jobs (e.g., diesel engine locomotive drivers, switchmen, forklift operators) was associated with an odds ratio of OR=1.53 (95%-CI: 1.04-2.24). CONCLUSIONS: The study provides further evidence that occupational exposure to diesel motor emissions is associated with an increased lung cancer risk.  相似文献   
58.
Background: Pars planta vitrectomy has evolved as an alternative method in the treatment of more complicated rhegmatogenous retinal detachments. We report a series of patients who underwent primary vitrectomy with gas tamponade without the use of additional scleral buckling. Methods: A retrospective study of 53 patients with a follow-up of 6–45 months (mean 17.8 months) was carried out. Preoperative findings included unusual, multiple or large breaks, vitreous haemorrhage, proliferative vitreoretinopathy and bullous retinal detachment. Preoperative visual acuity was between light perception and 1.0, with 30% (16/53) of patients with 0.4 or better. Results: Retinal reattachment was achieved in 64% of cases (34/53) with one and in 92% (49/53) with one or more operations. Final visual acuity was between light perception and 1.0, with 41% (22/53) of patients with 0.4 or better. Cataract formation occurred in 86% (37/43) of all patients with a clear lens preoperatively. Macular pucker was noted in 11 % (6/53) and postoperative proliferative vitreoretinopathy causing redetachment in 6% (3/53). Conclusion: With primary vitrectomy, a high final anatomical success rate with few intraoperative complications can be achieved in more complicated forms of rhegmatogenous retinal detachment. The major drawback of the procedure is the high incidence of post-operative cataract formation.  相似文献   
59.
In the Surgical Department of the University of Erlangen, 307 reconstructions in all areas of the arterial tree were performed with PTFE (GORE-TEX®) grafts, of which 188 were performed in the femoral-popliteal and femoral-crural areas. Femoral-popliteal bypass grafts above the knee joint remained patent in 93% of the patients during an average follow-up time of 6.7 months. Below the knee joint, the patency rate was 85% during an average follow-up time of 5.6 months. In the proximal aorta, aorta-renal, and aorta-femoral areas, long-term results with the PTFE graft have been excellent.  相似文献   
60.
The concentration of the metabolite of the beta-blocker metipranolol was determined in the aqueous humour of 89 cataract patients. At 1, 2 or 5 h before surgery, they received one drop (30 l) of a 0.1 % or 0.3% solution of the drug. At 1, 2 or 5 h after the application of 0.1 % metipranolol eye drops, desacetylmetipranolol concentrations of 624.55, 235.29 and 88.02 ng/ ml, respectively, were measured. At the same intervals after the instillation of 0.3% metipranolol eye drops, the respective values of 1289.20, 1120.88 and 327.36 ng/ ml were found. The metabolite concentration in the eye drops and the values measured show no consistent correlation.Offprint requests to: H. Bleckmann  相似文献   
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