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We investigated whether tumor cell/endothelia interaction can be influenced by platelet-activating factor (PAF, 1-O-alkyl-2-acetyl-sn-glycero-3-phosphocholine), a lipid mediator that promotes adhesiveness and extravasation of leukocytes in the inflammatory reaction. We found that the PAF receptor antagonist WEB 2086 prevents adhesion of melanoma Hs294T and colon carcinoma LS180 lines to IL-1-stimulated endothelial cells. Moreover, PAF stimulated the adhesiveness of Hs294T and LS180 cells to VCAM-1 and E- selectin, respectively, in an artificial model consisting of recombinant adhesive proteins bound to protein A-coated substrata. Thus, tumoral and not endothelial cell surface seems to be involved in the PAF-mediated enhancement of tumor cell adhesiveness to IL-1-activated endothelia. This observation is supported by the finding that Hs294T and LS180 cells express high affinity and functionally active receptors for PAF. By using specific inhibitors, we found that PAF-induced enhancement of cell adhesiveness was mediated by G-protein activation and protein tyrosine phosphorylation. In addition, protein tyrosine phosphorylation was observed in Hs294T and LS180 cells stimulated by PAF. In conclusion, we demonstrated that PAF-mediated activation of tumor cells enhances their adhesiveness to IL-1-stimulated vascular endothelia.  相似文献   
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AIM:To review the current literature regarding corrective osteotomies to provide the best evidence of the rule of bone grafting.METHODS:Our MEDLINE literature search included 280 studies using the following key words "Malunited distal radius fracture" and 150 studies using key words "Corrective osteotomy of the distal radius".Inclusion criteria were:Malunited distal radial,extra articular fracture,volar locking plate,use of iliac bone graft(cancellous or corticocancellous),non-use of bone graft.Twelve studies met the inclusion criteria.RESULTS:Seven of the 12 studies considered,described the use of a graft;the remaining five studies didn't use any graft.Type of malunion was dorsal in most of the studies.The healing time was comparable using the graft or not(mean 12.5 wk),ranging from 7.5 to 16 wk.The mean disabilities of the arm,shoulder and hand score improvement was 23 points both in the studies that used the graft and in those not using the graft.CONCLUSION:This review demonstrated that corrective osteotomy of extra-articular malunited fractures of the distal radius treated by volar locking plate does not necessarily require bone graft.  相似文献   
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The acquisition of the capacity to invade surrounding tissues confers a more malignant phenotype to tumor cells and is necessary for the establishment of metastases. The understanding of the molecular mechanisms underlying cell invasion in human solid tumors such as colorectal cancers could provide not only more sensitive prognostic analyses but also novel molecular targets for cancer therapy. We report in this article that K(+) ion channels belonging to the HERG family are important determinants for the acquisition of an invasive phenotype in colorectal cancers. The herg1 gene and HERG1 protein are expressed in many colon cancer cell lines, and the activity of HERG channels modulates colon cancer cell invasiveness. Moreover, the amount of HERG1 protein expressed on the plasma membrane is directly related to the invasive phenotype of colon cancer cells. Finally, both the herg1 gene and HERG1 protein were expressed in a high percentage of primary human colorectal cancers, with the highest incidence occurring in metastatic cancers, whereas no expression could be detected either in normal colonic mucosa or in adenomas.  相似文献   
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The purpose of this paper, after a brief review of the main features of bronchoprovocation challenges, was to determine whether the administration of an ultrasonic mist of distilled water can influence the bronchial tone of normal subjects and patients affected by various respiratory disorders, in order to assess the effectiveness of this bronchoprovocation test in discriminating between patients. Of the 129 subjects tested 13 were classified as normal, 60 as extrinsic asthmatics, 21 as intrinsic asthmatics, 25 as allergic rhinitics and 37 as chronic bronchitics. Ultrasonic mist, was administered for 5 min and the bronchial response was evaluated in terms of difference between that after the mist minus baseline values of specific airways conductance. The data suggest that the bronchial challenge with ultrasonic mist, a safe, non-pharmacological and simple test, allows a good discrimination between asthma patients and those affected by other respiratory disorders.  相似文献   
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BACKGROUND AND PURPOSE: The purpose of this study was to evaluate the efficacy of a preventive ergonomic intervention, which was provided by physical therapists, on spinal and upper-extremity work-related posture and symptom complaints of workers who use video display terminals (VDT). SUBJECTS: Two hundred employees who spent at least 20 hours per week at a VDT were randomly divided into 2 groups. Group E received the ergonomic intervention and an informative brochure, and group I received only the brochure. METHODS: Both groups were evaluated at the beginning of the study and at a follow-up 5 months later. The following tools were used: a pain drawing and the Rapid Entire Body Assessment (REBA) method to assess spinal and upper-extremity work-related posture. RESULTS: Group E had a lower REBA score and reduced lower back, neck, and shoulder symptoms compared with group I. DISCUSSION AND CONCLUSION: The results suggest that a personalized preventive ergonomic intervention can improve spinal and upper-extremity work-related posture and musculoskeletal symptoms for workers who use VDTs.  相似文献   
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Previous studies conducted in our laboratory showed that the reproduction of spontaneous and experimental metastases was reduced in host animals deprived of essential fatty acids (EFA). In the present study, we have explored the possibility whether apoptosis, proliferation, and angiogenesis might be involved in the antimetastatic effect of EFA deficiency. To this aim, in pulmonary colonies developed from B16-F10 cells in EFA-deficient animals or in animals fed a 5% corn oil diet, we performed an immunohistochemical analysis of bcl-2/bax proteins, PCNA, and VEGF and von Willebrand Factor (vWF), typical markers of apoptosis, proliferation, and angiogenesis, respectively. Apoptosis was also evaluated by detecting DNA fragments in metastatic cells. We found that the reduction of pulmonary colonies grown in EFA-deficient animals was associated with a high expression of apoptotic activity as revealed by the presence of apoptotic nuclei and a high immunoreactivity for bax. Cell proliferation seemed not to be influenced by EFA deficiency in view of the observation that PCNA was highly expressed in pulmonary colonies of control as well as EFA-deficient animals. Pulmonary colonies developed in EFA- deficient animals showed a lower expression of VEGF and a decreased microvessel density, indicating that a reduced angiogenesis contributes to the antimetastatic effects of EFA deficiency. Our analysis of the results invokes the possibility that a relationship between angiogenesis and apoptosis may account for the diminution of the development of experimental metastases in the lungs of EFA-deficient animals.  相似文献   
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