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1.
The present study investigated the expression of c-erbB-2 in 59 meningiomas, including different histological subtypes and anaplastic variants, by immunocytochemistry and molecular biological techniques. Immunohistochemistry using the monoclonal antibody FWP-51 directed against c-erbB-2-encoded oncoprotein gp185 demonstrated variable degrees of immunoreactivity in all meningiomas. The intensity of immunostaining correlated with the degree of expression as assessed by Western analysis in 28 meningiomas using polyclonal antiserum 21N. There was no correlation between the degree of expression and histological variants. Immunoreactivity of all menigiomas was distinctly less intense, however, than that of the human breast cancer cell line SK-BR-3, and slightly lower than that of brain metastases of breast and ovarian carcinomas that served as positive controls for both methods. By Southern analysis all meningiomas showed a single copy of the c-erbB-2 gene. Non-neoplastic arachnoid cap cells also exhibited c-erbB-2 expression and the degree of immunoreactivity was comparable with the majority of meningiomas. These data argue against an overexpression of c-erbB-2 in meningiomas, but rather indicate a cell-type-specific constitutive expression of the c-erbB-2 gene product in meningiomas and their putative progenitor cells. Since a subgroup of meningiomas is known to express progesterone receptors (PR), gp185 immunoreactivity was compared to the hormone receptor status using monoclonal antibody KD68. Fifty-six percent meningiomas showed PR immunoreactivity, but there was no statistically significant correlation with the degree of gp185 expression.This study was supported by a grant of the Tumorzentrum Heidelberg/Mannheim (M.K., No. 10028060)  相似文献   
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OBJECTIVE: The 'frozen' elephant trunk technique allows for single-stage repair of combined aortic arch and descending aortic aneurysms using a 'hybridprosthesis' with a stented and a non-stented end. This report summarizes the operative- and follow-up data (mean follow-up 14 months) with this new treatment. METHODS: Between 09/01 and 4/04, 22 patients (62+/-9 years; 9 female) with different aortic pathologies (15 aortic dissections, 7 aneurysms) were operated on after approval from the local institutional review board. The stented end of the hybridprosthesis was deployed in the descending aorta through the opened aortic arch during hypothermic circulatory arrest and selective antegrade cerebral perfusion. RESULTS: All patients survived the procedure but one patient died of acute hemorrhage due to rupture of the false lumen in the descending aorta on the second postoperative day. Two patients required reexploration of the chest for bleeding complications. In 2 of 4 patients who developed neurological dysfunction, symptoms resolved completely. In one of them, the descending aorta was perforated intraoperatively due to misplacement of the stented end of the hybridprosthesis. In all follow-up CT-scans thrombus formation in the descending aortic aneurysm excluded by the stented end of the hybridprosthesis has been observed. CONCLUSIONS: This procedure is performed through median sternotomy and combines the concepts of the elephant trunk operation and endovascular stenting of descending aortic aneurysms. Favourable intraoperative and postoperative results during follow-up with regard to thrombus formation around the stented descending aortic segment encourage us to evaluate all patients with thoracic aneurysms extending to proximal and distal of the left subclavian artery for this treatment.  相似文献   
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肱骨干骨折--髓内钉与钢板固定的比较   总被引:1,自引:1,他引:0  
总体而言,这些报道提示:采用髓内钉治疗肱骨干骨折较采用钢板带来更多的并发症,尤其是采用顺行人路。同时,这些报道没有提供确切的证据证明何种方法在骨折愈合、减少感染或上肢总体功能上优于另一种。  相似文献   
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BACKGROUND: Calcific aortic stenosis (AS), the most frequent heart valve disorder in developed countries, leads to the calcification and fibrous thickening of the valve. While several studies have addressed the process of valvular calcification, the molecular pathomechanisms of the extensive matrix remodeling remain unclear. Because inflammation is present in stenotic valves, we hypothesized that the proinflammatory cytokine tumor necrosis factor alpha (TNFalpha) might influence cell proliferation and regulate the expression and activation of matrix metalloproteinases (MMPs)--enzymes that are thought to be involved in calcific AS. METHODS: Immunohistochemistry for leukocytes, TNFalpha, MMP-1, and the endogenous MMP inhibitor tissue inhibitor of metalloproteinase (TIMP)-1 was performed on human stenotic (n = 19) and control (n = 8) valves. Primary cultures of human aortic valve myofibroblasts were incubated with and without TNFalpha, and cell proliferation was assessed. The expression and activation of MMP-1 were detected by Western blotting and a specific MMP-1 activity assay. RESULTS: Control valves showed scattered macrophages and low expression of TNFalpha, MMP-1, and TIMP-1. In stenotic valves, leukocyte infiltration and a strong, colocalized expression of TNFalpha and MMP-1 were present, while TIMP-1 remained unchanged. Double-label immunofluorescence localized TNFalpha mainly to macrophages. In cultured human aortic valve myofibroblasts, TNFalpha stimulated proliferation and induced a time-dependent increase in MMP-1 expression and activation, while TIMP-1 remained unchanged. CONCLUSION: The results indicate that matrix remodeling in calcific AS involves the expression and activation of MMPs. Activated leukocytes, by the secretion of TNFalpha, may stimulate valvular myofibroblasts to proliferate and express MMPs, thus regulating actively the matrix remodeling in calcific AS.  相似文献   
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Effect of depressive symptoms on survival after heart transplantation   总被引:3,自引:0,他引:3  
OBJECTIVE: This study explored the value of preoperative self-reported assessment for depression and anxiety in patients who had undergone heart transplantation (HTx). The initial sample was divided into subgroups of patients with ischemic (ICMP) and dilated cardiomyopathy (DCMP). Patient depression and anxiety scores were measured in both subgroups and their impact on pre- and postoperative mortality investigated. METHOD: An initial sample of 152 patients with either ICMP (N = 57) or DCMP (N = 95) and end-stage heart disease awaiting heart transplantation were assessed in a multidimensional longitudinal study, including psychological and somatic variables. One hundred and three patients received a HTx and were followed up for a mean of 4.4 years. Proportional hazard models were computed to test for the influence of psychosocial and somatic factors on outcome. RESULTS: Preoperative depression and state anxiety scores were significantly higher in the ICMP group. In addition to donor and recipient age, ICMP patients in the preoperative high depression group also showed a significantly higher mortality after HTx. This result remained significant even after controlling for sociodemographic and somatic variables. CONCLUSIONS: Patient self-reported depression, but not anxiety, can contribute to the identification of subgroups of patients with an unfavorable outcome after HTx. It therefore may be helpful to screen for depression, particularly in patients with an ischemic cause of their end-stage heart disease. Specific intervention programs should be further developed and evaluated.  相似文献   
10.
Haemophilia A is a X‐linked bleeding disorder, caused by deficiency in the activity of coagulation factor VIII due to mutations in the corresponding gene. The most common defect in patients is an inversion of the factor VIII gene that accounts for nearly 45% of individuals with severe hemophilia A. Point mutations and small deletions/insertions are responsible for the majority of cases with moderate to mild clinical course and for half of the severe hemophilia A occurrences. The majority of these mutations are “private”, because of the high mutation rate for this particular gene. We report on eleven pathological changes in the factor VIII sequence detected in male patients with haemophilia A or in female obligate carriers. Seven of these mutations are novel [E204N, E265X, M320T, F436C, S535C, N2129M and R2307P] and four have been previously identified [V162M, R527W, R1966X, and R2159C]. Genotype‐phenotype correlations and computer prediction analysis on the effect of missense mutations on the secondary structure of the factor VIII protein are performed and the relationships evaluated. © 2001 Wiley‐Liss, Inc.  相似文献   
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