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CXCL12 and its receptor, CXCR4, are emerging as promising targets for modulating growth, angiogenesis, and metastasis in several human cancers. Indeed, blocking the receptor is sufficient to prevent metastasis and angiogenesis in experimental breast cancer xenografts. Recently, the biological effect of the CXCR4 in pancreatic cancer, one of the most deadly neoplastic diseases, has been reported. However, the molecular mechanism by which CXCR4 contributes to these properties is not completely understood. In this paper, we characterize the signaling pathways activated by CXCR4 in pancreatic cancer. We show that after CXCR4 activation, EGFR becomes tyrosine phosphorylated, and the kinase activity of this receptor, together with the activation of MMPs, Src, and PI3-Kinase, is required for CXCR4-mediated ERK activation. Analysis of this cascade in pancreatic cancer cells revealed that the ERK-mediated pathway regulates genes involved in angiogenesis, such as VEGF, CD44, HIF1α, and IL-8. Furthermore, ERK blockage inhibits the migration and tube formation of endothelial cells induced by CXCL12. Considering that inhibitors for several components of this pathway, including CXCR4 itself, are at different stages of clinical trials, this study provides theoretical justification for the clinical testing of these drugs in pancreatic cancer, thus extending the list of potential targets for treating this dismal disease.  相似文献   
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Background  

Acromioclavicular injuries are common in sports medicine. Surgical intervention is generally advocated for chronic instability of Rockwood grade III and more severe injuries. Various methods of coracoclavicular ligament reconstruction and augmentation have been described. The objective of this study is to compare the biomechanical properties of a novel palmaris-longus tendon reconstruction with those of the native AC+CC ligaments, the modified Weaver-Dunn reconstruction, the ACJ capsuloligamentous complex repair, screw and clavicle hook plate augmentation.  相似文献   
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Primary mesenteric venous thrombosis: a study from western India.   总被引:1,自引:0,他引:1  
INTRODUCTION: The prevalence and clinical spectrum of mesenteric venous thrombosis (MVT) in India is largely unknown. METHODS: We retrospectively re-viewed the case records of patients with primary mesenteric venous thrombosis seen over a 10-year period and retrieved information on clinical picture, underlying hypercoagulable states and outcome. RESULTS: The 28 cases (mean age 41.2 [SD 10.2] years; 19 male) included 13 with acute MVT, 10 with subacute MVT and 5 with chronic MVT. Ten patients had past thromboembolic events (multiple events in five); four patients had isolated superior mesenteric vein involvement and 14 had multiple vessel involvement. Hypercoagulable state was identified in 17 patients, with multiple etiologies in 7 patients. Pre-operative diagnosis was made in all patients. Ten patients needed surgical management; the rest were managed medically initially, but 2 required surgery on follow up. Seven patients died during a follow up of up to 10 years, with in-hospital mortality during index admission in six. CONCLUSIONS: Most of the patients with MVT have multiple intra-abdominal vessel involvement and underlying hypercoagulable state. The policy of early treatment with anticoagulation in all and surgical treatment as per need, achieves low mortality.  相似文献   
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Congenital thoracic ectopic kidney is a very rare developmental anomaly and the rarest form of all ectopic kidneys. It is usually asymptomatic and discovered incidentally on routine chest radiography. Herein we reported the first case of staghorn stone in a thoracic kidney managed successfully by percutaneous nephrolithotomy.  相似文献   
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Aims and Objectives The significance of beaten copper appearance (BCA) on skull radiographs in children following surgery for isolated sagittal craniosynostosis has not been studied. This study was designed to look for any correlation between BCA and symptoms suggestive of intracranial hypertension in this group of patients. Materials and Methods Forty-eight consecutive children, who were operated for isolated sagittal synostosis from1987 to 2000 and had postoperative skull radiographs, were included. Patients were divided into: (a) BCA group (n = 20), consisting of children who had beaten copper appearance on skull radiographs at last follow up, and (b) Non-BCA group (n = 28), consisting of children who did not have this finding. Records were reviewed to look for symptoms suggestive of intracranial hypertension, such as headache, head banging, and irritability. Results Median age at surgery was 4.8 months for BCA group and 4 months for the non-BCA group. Follow up ranged from 4 to 156 months with a mean of 36.2 months. Total of 28.6% (n = 6) of the children with follow up radiographs done at ≤18 months of age had BCA. The incidence of BCA increased to 83.3% in children with skull radiographs performed after 48 months of age. In 18 (90%) children, the BCA was ‘diffuse’ with 5 (25%) children having the maximum possible score of 8. In the BCA group, 45% (n = 9) had symptoms compared to 10.7% (n = 3) in the control group (p = 0.0068). Conclusions This study suggests a significant number of children with BCA on radiographs develop symptoms suggestive of raised ICP following surgical treatment in infancy and prolonged follow up may be warranted in this group of patients.  相似文献   
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Duodenogastric reflux (DGR) has been implicated in several disease processes. The present study was carried out to document the incidence and evaluate the clinical significance of DGR after choledochoduodenostomy (CDD). A total of 13 patients who had undergone cholecystectomy with a standard side-to-side CDD for choledocholithiasis or chronic pancreatitis were studied by symptom evaluation, scintigraphy, endoscopy, and gastric mucosal histology at least 6 months after surgery. The scintigraphic findings were then compared with those of 10 patients who had undergone cholecystectomy alone. Only two patients (15%) had mild dyspeptic symptoms. The incidence of DGR after CDD was 69% compared to 20% in the cholecystectomy alone group (P < 0.05). In the majority of patients the DGR was only mild to moderate and the severity correlated well with the degree of endoscopic gastritis, but not with the clinical symptoms or histological findings. These results indicate that while CDD is associated with a high incidence of DGR, its occurrence does not produce significant clinical symptoms.  相似文献   
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