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91.
The aim of this study was to assess recovery, cell death, and cell composition of post-thaw cultured human islets. Cryopreserved islets were provided by the Clinical Islet Transplant Program, Edmonton, Canada. Islets were processed using media prepared in accordance with Pre-Edmonton and Edmonton protocols. Cryopreserved islets were rapidly thawed and cultured for 24 h, 3 d, 5 d, and 7 d, following which they were processed for histology. Islet quantification, integrity, morphology and tissue turnover were studied via hematoxylin and eosin stained sections. Ultrastructure was studied by electron microscopy and endocrine cell composition by immunohistochemistry. Using the Pre-Edmonton protocol, islet recovery was 50.1% and islet survival was 50% at 24 h while for the Edmonton protocol, the islet recovery was 69.4% (p < 0.001) and islet survival, 50% at ≈2.5 d. With an increasing culture duration although the physical integrity was retained there was an increasing loss of cohesivity both at light microscopic and at ultrastructure level regardless of the protocols used. Percentage islet survival and tissue turnover correlated negatively with culture duration in both protocols. The Edmonton protocol appears to preserve the islets better. However, culture duration adversely affects islet survival and quality, indicating the need for more optimal cryopreservation and culture techniques.  相似文献   
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AIM: Sargassum wightii Greville is a marine brown alga belonging to the Sargassaceae family which has about 200 species. The ethanolic extract of the whole dry plant powder contained numerous phytoconstituents, including flavonoids. The study was fo- cused on the anticancer activity ofSargassum wightii in mice. METHOD: The ethanolic extract ofSargassum wightii (EESW) at two dose levels was used to examine the anticancer activity in mice using DAL cell lines to induce cancer. The body weight, viable and non-viable tumor cell count, mean survival time, increase in life span, and hematological parameters were observed for anticancer activity of EESW. RESULTS: The intraperitoneal inoculation of DAL cells in mice significantly increased cancer cell count. The decrease in the cancer cell number observed in the EESW-treated group cancer animals indicates that the test drug has a significant inhibitory ef- fect on the tumor cell proliferation. Treatment with EESW also showed a significant decrease in tumor weight, and hence increased the lifespan of DAL-treated mice. In addition, EESW administration significantly restored the hematological parameters in DAL-treated mice. CONCLUSION: The present study results suggest that administration of extract offers enhanced antioxidant potential. Therefore it can be concluded from this study that EESW possesses anticancer activity.  相似文献   
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Oral tuberculosis is very rare and when present they are usually secondary to pulmonary tuberculosis. Tuberculous lesions of the tongue have become so infrequent that they are virtually a forgotten disease entity and may pose a diagnostic problem. The case reported in this paper emphasizes the importance of including tuberculosis in the differential diagnosis of any chronic oral ulcer. The low number of oral infections by M. tuberculosis could be due to underreporting.  相似文献   
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A strong promoter of bacteriophage MB78 does not have minus 35 consensus sequence although it has a TGn motif immediately upstream of minus 10 sequence as well as the AT rich UP element. It is efficiently recognised by the sigma 70 RNA polymerase, however, a phage-specific factor competes with sigma 70 RNA polymerase for binding to this region, the binding of the factor being stronger than that of the polymerase. Contrary to the reports in the literature the polymerase appears not to bind to the UP element whereas the phage-specific factor does. The latter seems to be involved in the regulation of the promoter activity. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   
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