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ABSTRACT: Canalicular adenomas are uncommon, benign epithelial neoplasm of the salivary glands that usually involve the upper lip and the buccal mucosa of elderly people. Differential diagnosis of the canalicular adenoma versus adenocarcinoma is important because it may result in unjustified radiotherapy or extensive and aggressive surgery. Despite the benign nature of canalicular adenomas, complete surgical removal and a regular clinical follow-up are recommended. The current study describes the diagnostic procedures, surgical management, and follow-up of a canalicular adenoma involving the palate of a 79-year-old man.  相似文献   
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Despite the high incidence, the molecular events involved in intestinal-type gastric carcinogenesis remains unclear. We previously established an intestinal-type gastric carcinogenesis model in Cebus apella, a New World monkey. In the present study, we evaluated hTERT and TP53 mRNA expression, as well as their protein immunoreactivity, in normal mucosa, non-atrophic gastritis, atrophic gastritis, intestinal metaplasia, and intestinal-type gastric cancer samples of non-human primates treated with N-methyl-nitrosourea. In addition, we evaluated the number of TP53 copies in these samples. Although hTERT immunoreactivity was only detected in gastric cancer, a continuous increase of hTERT mRNA expression was observed from non-atrophic gastritis to gastric tumors. No sample presented p53 immunoreactivity. However, we also observed a continuous decrease of TP53 mRNA expression during the sequential steps of gastric carcinogenesis. Moreover, loss of TP53 copies was observed in intestinal metaplasia and gastric cancer samples. Our study highlights that hTERT and TP53 have a key role in intestinal-type gastric cancer initiation.  相似文献   
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The optimal way to use immunomodulatory drugs as components of induction and maintenance therapy for multiple myeloma is unresolved. We addressed this question in a large phase III randomized trial, Myeloma XI. Patients with newly diagnosed multiple myeloma (n=2,042) were randomized to induction therapy with cyclophosphamide, thalidomide, and dexamethasone (CTD) or cyclophosphamide, lenalidomide, and dexamethasone (CRD). Additional intensification therapy with cyclophosphamide, bortezomib, and dexamethasone (CVD) was administered before autologous stem-cell transplantation to patients with a suboptimal response to induction therapy using a response-adapted approach. After receiving high-dose melphalan with autologous stem cell transplantation, eligible patients were further randomized to receive either lenalidomide alone or observation alone. Co-primary endpoints were progression-free survival (PFS) and overall survival (OS). The CRD regimen was associated with significantly longer PFS (median: 36 vs. 33 months; hazard ratio [HR], 0.85; 95% confidence interval [CI]: 0.75-0.96; P=0.0116) and OS (3-year OS: 82.9% vs. 77.0%; HR, 0.77; 95% CI: 0.63-0.93; P=0.0072) compared with CTD. The PFS and OS results favored CRD over CTD across all subgroups, including patients with International Staging System stage III disease (HR for PFS, 0.73; 95% CI: 0.58-0.93; HR for OS, 0.78; 95% CI: 0.56-1.09), high-risk cytogenetics (HR for PFS, 0.60; 95% CI: 0.43-0.84; HR for OS, 0.70; 95% CI: 0.42-1.15) and ultra-high-risk cytogenetics (HR for PFS, 0.67; 95% CI: 0.41-1.11; HR for OS, 0.65; 95% CI: 0.34-1.25). Among patients randomized to lenalidomide maintenance (n=451) or observation (n=377), maintenance therapy improved PFS (median: 50 vs. 28 months; HR, 0.47; 95% CI: 0.37-0.60; P<0.0001). Optimal results for PFS and OS were achieved in the patients who received CRD induction and lenalidomide maintenance. The trial was registered with the EU Clinical Trials Register (EudraCT 2009-010956-93) and ISRCTN49407852.  相似文献   
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We investigated the ultrastructural effects of the organophosphate compound methamidophos and treatment with atropine and pralidoxime (2-PAM) on rat kidneys. Male Wistar albino rats were assigned to four groups. Group 1 received 30 mg/kg methamidophos, the LD50 for this compound in rats, via oral gavage. Group 2 received only physiologic saline. Group 3 rats received 30 mg/kg methamidophos and were treated with 2-PAM and atropine via intraperitoneal injection when cholinergic symptoms were noted. Group 4 served as a control, and received physiologic saline in equivalent volumes and routes to Group 3. Kidney tissues were prepared for electron microscopic studies. No ultrastructural changes were detected in Group 1 after acute poisoning with methamidophos and in Group 3 treated with antidotes after poisoning. Acute organophosphate poisoning and antidotal treatment in this model are not associated with histopathological changes in the rat kidney but the models with different organophosphate compounds, by administrating the different dosages, may be more illuminative in explaining the effects of these chemicals in kidney.  相似文献   
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