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The majority of patients with curative resection of pancreatic ductal adenocarcinoma recur within 5 years of resection. However, the prognosis associated with different patterns of recurrence has not been well studied. A retrospective review of patients who underwent curative surgical resection of pancreatic cancer was performed. Of the 209 patients, 174 patients developed recurrent disease. Of these 174, 28(16.1%) had recurrent disease limited to lung metastases, 20(11.5%) had recurrence in the lung plus one or more other sites excluding the liver, 73(42.0%) had liver metastasis alone or liver metastasis with any other site except lung, 28(16.1%) local recurrence only, and 25(14.3%) peritoneal recurrence alone or together with local recurrence. Patients with recurrence limited to lung had a 8.5 months(Mo) median survival from recurrence to death, which was significantly better than the survival associated with recurrence in the liver(5.1Mo), in the peritoneum(2.3Mo) or locally(5.1Mo) in multivariable analyses. Among all groups, the time from surgery to the diagnosis of recurrence in patients who recurred in only in the lung was also the longest. However, 75% of patients were found to have indeterminate lung nodules on their surveillance CT scans prior to the diagnosis of recurrence in lung. This delayed diagnosis of lung recurrence may have a negative impact on survival after recurrence. In conclusion, pancreatic cancer with lung recurrence has a significantly better prognosis than recurrence in other sites. Further studies are needed to investigate how different diagnostic and treatment modalities affect the survival of this unique subpopulation of pancreatic cancer patients.  相似文献   
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Introduction

The aim of this study was to compare the glide path preparation times of stainless steel hand files, PathFiles (Dentsply Sirona, Ballaigues, Switzerland), and the WaveOne Gold Glider (Dentsply Sirona). The preparation times for final root canal shaping with the Primary WaveOne Gold instrument in extracted human molar teeth with and without prior glide path preparation were also recorded and compared.

Methods

Mesiobuccal canals of 60 extracted human mandibular molars (curvature angles between 25° and 35° and radii <10 mm) were selected and randomly divided into 4 groups with 15 canals each. Canals were negotiated to patency with a #8 K-file. Canal preparations were performed by a single operator using precurved #10-15-20 stainless steel manual K-files (the K-file group), a #10 stainless steel manual K-file followed by PathFiles #1-3 (the PathFile group), a #10 stainless steel manual K-file followed by WaveOne Gold Glider (the WaveOne Gold Glider group), or no further glide path preparation. Final canal preparation of all 60 canals was performed with the Primary WaveOne Gold instrument. Glide path and final preparation times were recorded.

Results

Glide path enlargement was statistically significantly fastest in the WaveOne Gold Glider group (19.7 ± 5.6 seconds) followed by the PathFile group (41.0 ± 6.8 seconds) and then the K-file group (81.2 ± 26.3 seconds) using analysis of variance (ANOVA) and Kruskal-Wallis tests (P < .0001). No statistically significant difference in the mean final preparation times was found among the WaveOne Gold Glider (23.1 ± 6.0 seconds), PathFile (24.4 ± 4.9 seconds), and K-file groups (27.2 ± 9.5 seconds). All 3 groups were statistically significantly faster than the no glide path preparation group (35.4 ± 10.2 seconds) using ANOVA (P = .0004) and Kruskal-Wallis tests (P = .0010).

Conclusions

Preparation time with the Primary WaveOne Gold file was statistically significantly reduced when the file was used in combination with any of the glide path preparation techniques. The WaveOne Gold Glider performed statistically significantly faster in glide path preparation time than the other glide path preparation techniques.  相似文献   
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Opsonization enhances Streptococcus pneumoniae-induced human monocyte-derived macrophage (MDM) apoptosis. Both depletion of complement and immunoglobulin from opsonizing serum and blockade of the macrophages CR1, CR3, FcgammaRII, and FcgammaRIII partially decreased MDM apoptosis after S. pneumoniae phagocytosis, and these effects correlated with reduced numbers of internalized bacteria. Chloramphenicol inhibition of protein synthesis by opsonized S. pneumoniae down-regulated subsequent MDM apoptosis. Phagocytosis of an unencapsulated mutant of S. pneumoniae resulted in increased MDM apoptosis, in association with enhanced internalization. Caspase inhibition was associated with decreased killing of bacteria. Enhanced induction of apoptosis by opsonized S. pneumoniae is the result of increased intracellular burden of bacteria, rather than of a specific pattern of engagement of complement receptor or FcgammaR. A dynamic interaction between live intracellular bacteria and the host cell is necessary for induction of apoptosis in MDMs, and induction of apoptosis contributes to the host defense against S. pneumoniae.  相似文献   
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Colorectal cancer (CRC) chemoprevention is an area of interest. Non-steroidal anti-inflammatory drugs (NSAIDs) are anti-inflammatory agents which have been identified as cancer chemoprevention agents given that inflammation is thought to contribute to tumorigenesis. Most studies have demonstrated that the NSAID, aspirin, plays a beneficial role in the prevention of CRC and colonic adenomas. Non-aspirin NSAIDs (NA-NSAIDs) have also been studied in CRC chemoprevention. There is increasing literature around their role in pre-cancerous polyp prevention and in decreasing CRC incidence and CRC-related outcomes in certain high-risk subgroups. However, the use of NA-NSAIDs may be accompanied by increased risks of toxicity. Further studies are required to establish the associations between concurrent aspirin and NA-NSAID use, and CRC-related outcomes.Subject terms: Colorectal cancer, Cancer prevention  相似文献   
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An immunohistochemical study of p53 protein was carried out on 45 salivary gland lesions using a monoclonal antibody, Bp53–12, raised to the intracellular domain of the p53 protein. p53 protein expression was found in 34.4% of 32 salivary gland carcinomas. Nuclear p53 expression was detected in tumor cells but not in non-neoplastic cells, except in one salivary duct carcinoma. The perinuclear cytoplasm of luminal duct cells was specifically positive for the antibody used here. Cytoplasmic p53 expression was observed mostly in non-neoplastic cells. There was a tendency for the Cytoplasmic staining of p53 protein to be observed in the normal cells adjacent to p53-positive carcinomas, but none of the normal cells were positive in the tissues surrounding p53-negative carcinomas. Cytoplasmic expression of p53 protein in salivary gland tissues seems to be correlated with tumorigenesis.  相似文献   
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