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31.
The adult mammalian central nervous system (CNS) lacks the capacity to support axonal regeneration. There is increasing evidence to suggest that astrocytes, the major glial population in the CNS, may possess both axon-growth promoting and axon-growth inhibitory properties and the latter may contribute to the poor regenerative capacity of the CNS. In order to examine the molecular differences between axon-growth permissive and axon-growth inhibitory astrocytes, a panel of astrocyte cell lines exhibiting a range of axon-growth promoting properties was generated and analysed. No clear correlation was found between the axon-growth promoting properties of these astrocyte cell lines with: (i) the expression of known neurite-outgrowth promoting molecules such as laminin, fibronectin andN-cadherin; (ii) the expression of known inhibitory molecules such tenascin and chondroitin sulphate proteoglycan; (iii) plasminogen activator and plasminogen activator inhibitor activity; and (iv) growth cone collapsing activity. EM studies on aggregates formed from astrocyte cell lines, however, revealed the presence of an abundance of extracellular matrix material associated with the more inhibitory astrocyte cell lines. When matrix deposited by astrocyte cell lines was assessed for axon-growth promoting activity, matrix from permissive lines was found to be a good substrate, whereas matrix from the inhibitory astrocyte lines was a poor substrate for neuritic growth. Our findings, taken together, suggest that the functional differences between the permissive and the inhibitory astrocyte cell lines reside largely with the ECM.  相似文献   
32.
External fixation is an apparently simple and therefore highly fascinating method for the stabilization of fractures.Minimally invasive incisions guarantee that regional soft tissue perfusion is conserved after trauma,which makes it the best procedure for stabilization of fractures combined with severe soft tissue damage.However, modern trauma surgery is subject to cyclical trends in the same way as fashion is; noninternal devices are currently barely tolerated.The literature suggests that specialists are virtually competing to see who can stabilize fractures with the most severe soft tissue damage by internal procedures – with the best results, of course. It seems, then, that times are hard for external fixation, but we still believe that for fractures with severe soft tissue damage external fixation still brings a lot of benefit to the patient.  相似文献   
33.
BACKGROUND: The problems associated with rectal surgery are frequently discussed with no reference being made to the distance of the tumor from the anal verge. This study examined the effect of the location of the tumor on early postoperative results. PATIENTS AND METHODS: This was a multicenter study involving 75 German hospitals and 3756 patients, of whom 1463 had rectal carcinoma. On the basis of the location of the tumor (distance from the anal verge), four groups were distinguished: <4, 4-7.9, 8-11.9, and 12-16 cm. RESULTS: Resection and abdominoperineal resection rates and the incidence of postoperative complications depended on the location of the tumor. Significantly higher resection rates and fewer specific complications, and a significant reduction in overall postoperative morbidity were found with tumor locations more than 8 cm from the anal verge. The highest anastomotic leak rate was observed with anastomoses less than 7 cm from the anal verge. The logistic regression showed that the distance of the tumor from the anal verge is an independent variable for the development of an anastomotic leak. CONCLUSIONS: Early results are greatly affected by the location of the rectal carcinoma. This applies to both abdominoperineal resection rates and specific postoperative complications, such as anastomotic leak rate and operation morbidity in general.  相似文献   
34.
BACKGROUND: The efficacy of nasal continuous positive airway pressure (nCPAP) as a prophylactic method for preventing cardiopulmonary complications after major vascular surgery has not been investigated. PATIENTS/METHODS: In a prospective randomized trial, 204 patients undergoing elective midline laparotomy for vascular surgery were randomized to receive standard therapy ( n=105) or additional prophylactic nCPAP ( n=99) for the first postoperative night. Postoperative oxygenation, incidence of severe cardiac, and pulmonary complications, length of intensive care surveillance and length of total postoperative hospital stay (LOS) were compared. RESULTS: Prophylactic nCPAP significantly reduced the number of patients with severe oxygenation disturbances defined as paO(2) < 70 mmHg with FiO(2) > or = 0.7 (5 versus 17, P=.01). There were no differences with respect to death, cardiac and pulmonary complications, length of intensive care surveillance or LOS. CONCLUSION: Prophylactic 12 h nCPAP significantly reduces the occurrence of postoperative oxygenation disturbances but has no effect on cardiac or pulmonary complications, need for intensive care, LOS or mortality after major vascular surgery.  相似文献   
35.
SUMMARY: Poor tolerance and the potential long-term toxicity have limited the widespread use of corticosteroids and cytotoxic drugs in the treatment of idiopathic membranous nephropathy (IMN). Cyclosporin A (CyA) has been proven to be a less toxic alternative, but its efficacy needs further confirmation. Cyclosporin A (2–3mg/kg per day) in combination with low-dose methylprednisolone (4mg/day) was given to 28 nephrotic patients with IMN who had failed to respond, or tolerate, or to complete treatments with steroids and/or cytotoxic drugs. the mean duration of treatment was 11 ± 7 months. Seven patients (25%) showed a complete remission of proteinuria, 17 (60%) a partial one, and four (15%) did not respond at all. the average time to achieve optimal remission was 4.2 ± 1.4 weeks following the initiation of therapy. In those who responded completely or partially, plasma creatinine (Per) did not change significantly from pre CyA levels during follow up (1.0 ± 0.3 vs 1.2 ± 0.3mg/dL, P =NS). the remaining four patients who had renal insufficiency already before CyA (mean Per: 2.1 ± 0.8mg/dL), showed a rapid deterioration of renal function after the initiation of CyA (mean Per: 3.1 ± 1.5 mg/dL, P <0.01), and as a consequence, the drug was discontinued. A mul-tivariate analysis on the clinical and histological features demonstrated that the degree of renal function impairment ( P <0.02), the percentage of obsolete glomeruli ( P <0.01), and the severity of interstitial fibrosis ( P <0.005) independently predicted the response to therapy. Low dose CyA is an effective and safe alternative treatment for patients with IMN and normal renal function. However, the drug should be given with caution to patients with established renal insufficiency.  相似文献   
36.
Trauma und Berufskrankheit - Zusammenfassung Der Processus coronoideus ist der wichtigste knöcherne Stabilisator des Ellbogengelenks, der vordere Anteil des Lig. collaterale ulnae, welcher am...  相似文献   
37.
The treatment of deep cartilage defects in load-bearing joints is a problem that still has no satisfactory solution. Full-thickness defects of the articular cartilage rarely heal spontaneously, usually leaving damage that can lead to early arthrosis. Techniques currently available for the treatment of chondral defects include abrasion, drilling, micro-fracturing, transplantation of tissue autografts and allografts, and cell transplantation. Osteochondral autograft transplantation is currently the only surgical cartilage repair technique known to lead to the formation of genuine hyaline articular cartilage and its retention at least in the medium term. The Draenert method, in which a water-cooled diamond bone-cutting system is used, is an effective procedure for resurfacing the joints affected by localised cartilaginous defects, even when there is also severe bone loss. Donor-side morbidity can be kept to a minimum by filling the defect caused by harvesting with a press-fit cylinder of cancellous bone covered with periosteum for protection.  相似文献   
38.
39.
Occupational diseases Nos. 2108 and 2110 correspond to intervertebral disc-related diseases of the lumbar spine from many years of carrying or lifting heavy loads, occupations in extreme postures of full flexion or oscillation of the whole body when seated, and which compel the cessation of all activities which are or could be the cause for the origin, exacerbation or recurrence of the disease. These occupational diseases came into force at the start of 1993, but there have been considerable problems in their implementation. The present Part I of the contribution is the result of the work of an interdisciplinary study group and contains medical criteria for the assessment of possibly strain-related clinical characteristics and the evaluation of other possible causes. Part II is to be published in Volume 4/2005 and will deal with questions related to forced cessation and to the assessment of the loss of earning ability. Agreement was reached in many areas related to the assessment of occupational claims. This should allow for evidence-based decision making in the future for the occupational diseases Nos. 2108 and 2110.  相似文献   
40.
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