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1.
GL Baum 《Canadian Metallurgical Quarterly》1996,334(21):1404; author reply 1404-1404; author reply 1405
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Synergism between recombinant human tumour necrosis factor (rHuTNF) and DNA topoisomerase II inhibitor VP16 during the killing of cells has been studied in six human ovarian cancer cell lines (A2774, A2780, SW626, IGROV-1, SKOV3, Pa1) and a cervical carcinoma cell line (Me180). Studies were performed using an assay of colony formation inhibition (drug treatment for 1 h) and a growth inhibition assay (continuous exposure for 20 h). Concomitant treatment of cells with VP16+rHuTNF enhanced cell killing in all the cell lines tested--an effect observed in both short- and long-term cytotoxicity assays. This study suggests that the activity of VP16 in ovarian cancer cell lines might be enhanced by rHuTNF in in vitro models.  相似文献   
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One hundred and twelve bilateral thyroidectomies for solitary thyroid nodules with suspected malignancy were performed. The incidence of malignancy in the 112 primary nodules was 42%. Twenty-nine of the 112 contralateral lobes (26%) contained malignancy, which was unsuspected in 80%. Of these 29, 20 were foci of papillary cancer < or = 5 mm and 9 were larger papillary tumors or follicular carcinoma. We analyzed these 112 patients to determine whether there was a simple method to identify those patients at risk for contralateral, unsuspected malignancy. With use of the AMES clinical staging retrospectively, 70 of the 112 patients were classified as having low-stage disease. Fifty percent (35) had cancers on the primary side and 27% (19) on the contralateral side. Of these 19 contralateral cancers, 14 were papillary cancers < or = 5 mm, 4 were papillary cancer > 5 mm and one was a 1.5 cm follicular carcinoma, a similar distribution as in the whole group of 112. When the AMES analysis then excluded those thought to be at risk for multicentricity or papillary carcinoma and examined female patients only with nonpapillary frozen sections, nonpapillary aspiration cytological results, and no history of radiation exposure, no further reduction in the proportion of contralateral cancers (7 of 26, 27%) was found. Fifty-five of the 112 patients underwent preoperative ultrasound scans. In those cases in whom the contralateral lobe had no intraoperative palpable or preoperative sonographic mass, 5 of 20 still had contralateral cancers, but all were papillary < or = 5 mm.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
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Osteomyelitis in uncommon locations can present unusual diagnostic difficulties. A patient with primary sternal osteomyelitis who presented with pain over the right supraclavicular area and a radiologic picture of a pleural-based right upper lung mass is discussed. A triple-phase bone scan was consistent with the diagnosis, and a needle aspiration of the mass revealed a staphylococcal abscess. Percutaneous drainage of the contiguous abscess and a prolonged course of antibiotic therapy cured the infection.  相似文献   
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Infrared and UV–vis studies of metallocene immobilization on silica are reported here. The results have indicated changes in the Zr coordination sphere of metallocene depending on the immobilization route used. The reaction of [(Cp)2ZrCl2] with silica formed [(Cp)2ZrCl]+[SiO] species. The same metallocene, reacting with TMA modified silica, formed monomethylated and dimethylated species by the substitution of chloro for methyl ligands, stabilized on the surface by interaction with “MAO-like” species (methylaluminoxane, MAO). These monomethylated and dimethylated cationic zirconium species are the active centers for the polymerization reaction. Different order of TMA addition in the silica modification step generated surface species of a similar nature, differing in their relative quantities. The highest amount of these active species was obtained when the support was added to the TMA solution rather than adding the TMA solution to the silica support. This was the most significant parameter affecting catalytic activity in ethylene polymerization.  相似文献   
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Ultrastructure of sperm and eggs of the ocean pout (Macrozoarces americanus L.), an internally fertilizing marine teleost, was examined by scanning and transmission electron microscopy. The results showed that the sperm do not have an acrosome but have a very long mid-piece (one to two times the sperm head length) containing numerous well-developed elongated mitochondria. The sperm also have two tails (is biflagellate) each consisting of nine peripheral and one central pair (9 +/- 2) of microtubules. This long mid-piece and the biflagellate nature of the sperm appear to be associated with the long life-span of the sperm and with sperm dispersal in the ovary to fertilize the eggs internally. The ocean pout eggs are enveloped by a porous chorionic membrane similar to that found in other teleosts but have two micropyles, a condition likely related to a mechanism of egg fertilization which increases the egg fertility in the presence of low sperm numbers. Following insemination, some biochemically undefined excretions appeared on the surface of fertilized eggs and led to the acquisition of adherent capability of the eggs which formed a tightly associated egg mass in sea water.  相似文献   
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Free-living nematodes may harbor, protect, and disperse bacteria, including those ingested and passed in viable form in feces. These nematodes are potential vectors for human pathogens and may play a role in foodborne diseases associated with fruits and vegetables eaten raw. In this study, we evaluated the associations between a free-living soil nematode, Caenorhabditis elegans, and Escherichia coli, an avirulent strain of Salmonella Typhimurium, Listeria welshimeri, and Bacillus cereus. On an agar medium, young adult worms quickly moved toward colonies of all four bacteria; over 90% of 3-day-old adult worms entered colonies within 16 min after inoculation. After 48 h, worms moved in and out of colonies of L. welshimeri and B. cereus but remained associated with E. coli and Salmonella Typhimurium colonies for at least 96 h. Young adult worms fed on cells of the four bacteria suspended in K medium. Worms survived and reproduced with the use of nutrients derived from all test bacteria, as determined for eggs laid by second-generation worms after culturing for 96 h. Development was slightly slower for worms fed gram-positive bacteria than for worms fed gram-negative bacteria. Worms that fed for 24 h on bacterial lawns formed on tryptic soy agar dispersed bacteria over a 3-h period when they were transferred to a bacteria-free agar surface. The results of this study suggest that C. elegans and perhaps other free-living nematodes are potential vectors for both gram-positive and gram-negative bacteria, including foodborne pathogens in soil.  相似文献   
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岩心PI值试验研究及应用   总被引:5,自引:0,他引:5  
主要论述了在多功能采油化学用剂评价仪上进行的岩心PI值试验的步骤,现象及结论。重点考察了岩心PI值与渗透率、流量及注入截面面积的关系;平行管岩心复合PI值和其中单管岩心PI值的关系。  相似文献   
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