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1.
Epstein-Barr virus (EBV) has been implicated as a causal virus of gastric cancer with episomal monoclonality, elevated antibodies and a unique morphologic expression in the early intramucosal stage, but the infection mechanisms have not been demonstrated. EBV has been shown only in the cancerous lesions by the highly sensitive EBV-encoded small RNA in situ hybridization (EBER-ISH) method, not in the dysplastic mucosa adjacent to the cancer. A case is presented of multiple EBV-positive gastric cancer and dysplastic epithelium observed in a 52-year-old man. Serial cut sections of the gastrectomy specimen showed four small cancerous lesions, three of which were EBER-positive, and three EBER-positive, minute, non-cancerous dysplastic lesions. The three cancerous lesions were intramucosal cancer, with one having minimal submucosal invasion forming a lymphoepithelioma-like histology. All of these EBER-positive cancerous and dysplastic lesions showed intense CD8 T-lymphocytic infiltration. There was no such findings in the EBV-negative cancerous lesion. It was concluded that EBV infection may occur in the epithelial cells of atrophic gastric mucosa, and progress to cancer with monoclonal expansion through the EBV-positive dysplastic change. Cytotoxic T-lymphocytic reactions can occur even in the dysplastic lesions. Multifocal EBV infection in the gastric mucosa may occur and, if necessary, total gastrectomy is recommended in such a case.  相似文献   
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Motility related protein 1 (MRP1/CD9) expression in colon cancer   总被引:1,自引:0,他引:1  
STUDY OBJECTIVES: To examine the incidence and clinical significance of prolonged air leak (PAL) in patients undergoing radical upper lobectomy and to determine potential risk factors for PAL in this group of patients. DESIGN: Retrospective review of a prospective database. SETTING: Experience of one thoracic surgeon at a tertiary care cancer center. PATIENTS: One hundred consecutive patients undergoing right upper lobectomy and mediastinal lymph node dissection for non-small cell lung cancer over an 11-year period. MEASUREMENTS: PAL was defined as an air leak lasting >7 days. Preoperative, intraoperative, and postoperative clinical data were collected and analyzed to determine the factors associated with PAL. RESULTS: PAL was the most prevalent postoperative complication, comprising 25.5% of all complications seen, and lasting an average of 12.1+/-5.3 days. In 21 of the 26 patients with PAL, this complication was the only morbidity identified. There was no statistically significant difference in patient age, gender, preoperative FEV1 and diffusion of carbon monoxide, exposure to neoadjuvant chemotherapy, status of pulmonary fissures, or pathologic stage between the PAL group vs the remaining 74 patients without this complication. A significantly greater proportion of patients with PAL had FEV1/FVC ratio < or =50% (6/26 vs 5/74; p=0.02). Patients with PAL had significantly longer median length of hospital stay (11 vs 7 days; p=0.0001). Moreover, PAL was the single most common reason for an extended length of hospitalization (21/58, 36% of all causes). CONCLUSION: PAL is an alarmingly common postoperative complication and is the most frequent cause of an extended length of hospital stay in patients undergoing radical upper lobectomy. Severe obstructive pulmonary disease predisposes patients to the development of this complication.  相似文献   
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Small cetaceans (toothed whales odontoceti and dolphins delphinidae) have been traditionally hunted along the coast of Japan and fresh red meat and blubber, as well as boiled internal organs such as liver, kidney, lung and small intestine, are still being sold for human consumption. We surveyed mercury contamination in boiled liver, kidney and lung products marketed in Japan between 1999-2001. The average +/- S.D. of total mercury (T-Hg) was 370 +/- 525 (range: 7.60 approximately 1980, n = 26) microg/g in liver, 40.5 +/- 48.5 (7.30-95.1, n = 15) microg/g in kidney and 42.8 +/- 43.8 (2.10-79.6, n = 23) microg/g in lung. A high correlation was observed between T-Hg and selenium (Se) concentrations in these organs, supporting the formation of a Hg-Se complex. The formation of a Hg-Se complex probably contribute to the detoxification of Hg for cetaceans and allows a very large accumulation of Hg in livers. The provisional permitted level of T-Hg in marine foods set by the Japanese Ministry of Health and Welfare is 0.4 microg/ g, and the provisional permitted weekly intake (PTWI) set by WHO is 5 microg/kg bw/week. The maximal T-Hg detected in boiled liver (1,980 microg/g) exceeds the permitted level by approximately 5,000 times and the consumption of only 0.15 g of liver exceeds the PTWI of 60 kg of body weight of the consumer, suggesting the possibility of an acute intoxication by T-Hg even after a single consumption of the product.  相似文献   
5.
Human T cell leukemia virus type I (HTLV-I) is a retrovirus that is not lysed by human serum or complement. It has not been determined, however, whether HTLV-I directly binds to complement components or whether it retains infectivity after incubation with human serum. We investigated the effects of human serum on the infectivity of cell-free HTLV-I produced by human and animal cells. Plating of vesicular stomatitis virus (HTLV-I) pseudotypes prepared in cat or human cells and formation of HTLV-I DNA after infection of cell-free HTLV-I produced by cat or human cells were markedly inhibited by treatment with fresh human serum, but not by heat-inactivated serum. HTLV-I infection was also inhibited by treatment with C2-, C3-, C6-, or C9-deficient serum, but not by C1q-deficient serum. Inhibitory activities of normal human serum against HTLV-I were neutralized by anti-C1q serum. Furthermore, purified C1q inhibited HTLV-I infection. The direct binding of C1q to HTLV-I was confirmed by comigration of C1q with HTLV-I virion upon sucrose density gradient ultracentrifugation of HTLV-I virion treated with C1q. Binding assay using synthetic envelope peptides indicated that C1q bound to an extramembrane region of the gp21 transmembrane protein. These findings indicate that the human complement component C1q inactivates HTLV-I infectivity.  相似文献   
6.
The formation and the phase transitions of iron silicide by solid-phase epitaxy have been investigated by means of plan-view transmission electron microscopy, which enables us to observe a clean interface between Fe and Si. Layers of Fe were deposited on Si (100) at room temperature in an ultrahigh vacuum chamber. The sample was annealed in the electron microscope at a temperature between 673 and 1073 K. After annealing at 673 K, FeSi crystallites were formed with various orientations. When the annealing temperature was increased to 973 K, we found that the crystallites suddenly started to coalesce into grains of several hundreds of nanometers in size and polycrystalline beta-FeSi2 was formed. These phase transitions were also confirmed with electron energy-loss spectroscopy.  相似文献   
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The progress of silicon technology is opening the era of “systems on silicon” in which a large-scale memory, a CPU, and other logic macros will be integrated on a single chip. These kinds of chips, called system LSIs, have an especially promising future in mobile and multimedia applications but face inherent technical problems related to the reliability of ultrathin oxide film, conflict in the processing of different components, increased gate and subthreshold leakage currents, memory bottlenecks, and design complexity. This paper reviews the system LSIs and then introduces related technologies in processing, circuits, chip architecture, and design. It also discusses the influence of the system LSIs on business strategies.  相似文献   
8.
We designed a new bag-carrier device system for continuous intravenous hyperalimentation. The patient carries it on his shoulder and can both walk up and down stairs and go out. The use of this device is simple and easy, and was found to increase the patient's opportunity to engage in physical activity.  相似文献   
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A 200-MHz double-data-rate synchronous-DRAM (DDR-SDRAM) was developed. The chip contains a delay-locked loop (DLL) which performs over a wide range of operating conditions. Post-mold-tuning allows precise replica programming. A 200-MHz intra-chip data bus is suitable for DDR operation  相似文献   
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