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91.
Cotransfection of a transformation-deficient and immortalization-positive SV40 early gene mutant with various constructs of viral promoter-linked myc genes induced dense foci in 3Y1 cells, an established cell line derived from rat embryo fibroblasts, whereas transfections with either species alone did not. Four cell clones were isolated from colonies grown in soft agar medium, and found to contain at least a single copy of both DNA species and to express both sequences at relatively high levels. These results indicate that the two immortalizing genes used in the present study collaborate to transform 3Y1 cells.  相似文献   
92.
A novel glutathione-conjugated metabolite of morphine has been isolated from the bile of guinea pigs given morphine. The metabolite was separated by preparative HPLC on a reverse phase column (YMC-GEL C18) using methanol/water (1:4, v/v) as eluate and purified by HPLC on another reverse phase column (mu-Bondapak phenyl) using water/acetonitrile/trimethylamine/acetic acid (150:3:2:1, v/v) as a mobile phase. The unambiguous structure assignment of the metabolite was performed by fast atom bombardment mass spectrometry and 400 MHz fourier transform NMR spectrometric analysis, and it was identified as (8S)-glutathion-S-yl)dihydromorphinone, in comparison with the synthetic morphinone-glutathione adduct.  相似文献   
93.
The influence which malnutrition plays on the host-tumor relationship is controversial because of the disparity of human and rodent tumors, a critical difference being the minimal immunogenicity of human tumors and the variable antigenicity of rodent tumors. The hypothesis we tested is that the influence of malnutrition on tumor growth is a result of the immunogenicity of the host's tumor. C-1300 neuroblastoma (NB) is an immunogenic tumor by in vivo and in vitro assessment while the histologically identical TBJ-NB clone is non-immunizing. Isogeneic A/J mice were malnourished with 2.5% protein chow and were inoculated with C-1300-NB or TBJ-NB; either serial tumor volumes were assessed by three-dimensional measurement or animals were serially killed and tumor weight/carcass weight ratios (TW/CW) were calculated. Non-immunogenic TBJ-NB grew more rapidly than C-1300-NB in both control and malnourished groups, but there was no difference in either tumor size or TW/CW ratios between the two TBJ-NB nutritional groups. Contrasting with these data were immunogenic C-1300-NB in that the tumor grew significantly better in malnourished mice (tumor volume p less than 0.05 day 12 and 14; TW/CW p less than 0.026 by day 21). Prior whole-body irradiation abrogated this difference. These data demonstrate that for tumors differing only in antigenicity the influence of malnutrition is on that tumor which induces an immunologic antitumor response.  相似文献   
94.
Intraoperative monitoring of anorectal pressure was used in a case of sacral lipomeningocele accompanied by congenital dermal sinus to protect the physiological function of the anorectal sphincters. This monitoring system consists of a manometric anorectal balloon and neural electrical stimulation. The system was able to differentiate functioning neural structures from surrounding tissues during the operation.  相似文献   
95.
Eight adult cats of either sex were studied. The minimal alveolar concentration (MAC) for sevoflurane in the cats was found to be 2.58 ± 0.30% (mean ± SD). The ratios of MAC values between sevoflurane and halothane, enflurane and isoflurane in cats were very similar to those ratios found in humans and dogs. This observation suggests that the results of this study are correct and allows us to estimate unknown MAC values for sevoflurane in other species using known MAC values for other anesthetic agents.(Doi M, Yunoki H, Ikeda K: The minimum alveolar concentration of sevoflurane in cats. J Anesth 2: 113–114, 1988)  相似文献   
96.
Serum interleukin 6 levels become elevated in acute myocardial infarction.   总被引:9,自引:0,他引:9  
We have examined serum interleukin 6 (IL-6) levels in 12 patients with acute myocardial infarction (AMI). IL-6 levels became elevated in all patients, following the rise of serum creatine kinase (CK) activity. Peak IL-6 levels showed a good correlation with peak serum C-reactive protein (CRP) levels, while there was no direct relationship between peak IL-6 levels and peak CK activity. IL-6 mRNA was not detected in unstimulated "quiescent" rat cardiocytes cultured in serum-free medium, but its expression was induced by exposure of the cells to serum or ionomycin. These results show that IL-6 is synthesized in the myocardium and serum IL-6 levels become elevated in AMI, suggesting that IL-6 could affect the progression and/or healing processes of AMI.  相似文献   
97.
To evaluate the development of renal hypoxia during hemorrhagic shock, fourteen dogs were induced in this study. The animals were divided equally into a group in which mean arterial pressure (MAP) was kept at 50mmHg (group 1), and into another where MAP was kept at 40mmHg for 180mim (group 2). Renal tissue gas tensions were determined by a mass spectrometer. In the 50-mmHg group, renal tissue oxygen tension (PrO 2) dropped for 15min following hemorrhage, remained constant for 90min, then fell further for 150min before a plateau was established. In the 40-mmHg group, the PrO 2 dropped for 90min before reaching a plateau. The second PrO 2 decline occurred at the same level in both the 50-mmHg group and the 40-mmHg group. The point at which the same PrO 2 level occurred for each group suggests the cessation of oxygen consumption and the conditions of renal hypoxia. It is assumed that renal hypoxia occurs in 120min at a MAP of 50-mmHg and in 60min at a MAP of 40mmHg.(Murakawa K, Izumi R, Kobayashi A: Renal tissue gas tentions during hemorrhagic shock. J Anesth 3: 10–15, 1989)  相似文献   
98.
Summary Physicochemical properties of two types of adriamycin preparation, suspensions and emulsions prepared for i.a. chemotherapy of hepatocellular cacinoma, were investigated. A suspension was prepared by dispersing adriamycin directly into the lipid contrast medium, Lipiodol, whereas an emulsion was obtained by emulsifying an aqueous solution of adriamycin into Lipiodol. The dispersibility of the drug in each preparation was examined microscopically. The chemical stability of and drug release from the preparation were determined by high-performance liquid chromatography and spectrophotometry, respectively. The suspension was then given to ten patients with primary hepatocellular carcinoma. The suspension maintained good dispersibility without coagulation of drug particles, whereas coalescence of aqueous droplets and the resultant phase separation occurred 4 h after preparation of the emulsion. Both preparations maintained the initial drug content for at least 1 week at room temperature. The release of adriamycin was more prolonged in the suspension than in the emulsion. After i.a. administration of the suspension, a selective accumulation of Lipiodol in the tumor and decrease in serum -fetoprotein (AFP) levels were found in most patients. A significant amount of adriamycin was still detected in hepatic speciments resected from two patients 1 and 2 months after treatment. These findings suggest that the adriamycin-Lipiodol suspension may be a useful preparation for targeting chemotherapy to hepatocellular carcinoma.  相似文献   
99.
Neokadsuranic acid A, which is the first triterpenoid with the 14(13-->12) ABEO lanostane skeleton, was isolated from KADSURA HETEROCLITA together with (24 Z)-3-oxo-lanosta-8,24-dien-26-oic acid. The present paper deals with the isolation and structure elucidation of these two new compounds.  相似文献   
100.
Thymidylate synthase (TS) and dihydropyrimidine dehydrogenase (DPD) has been suggested to be sensitivity-limiting factors of 5-fluorouracil therapy in cancer patients. We conducted a large-scale population study on the activity of TS and DPD in patients with various solid tumors. A total of 2590 clinically removed tumors, consisting of 1112 colon, 724 gastric, 520 breast, and 236 non-small cell lung cancers, were provided to measure TS and DPD activity. TS activity in the gastric, colon, and non-small cell lung cancers was significantly higher than in matched non-cancerous tissue (P<0.0002), but there was no difference in TS expression between tumor and non-cancerous tissue from breast cancer patients. Gastric, breast, and non-small cell lung cancers showed significantly higher DPD activity than their corresponding non-cancerous tissues, but colon cancers did not. There was no correlation between TS activity and DPD activity, and thus each enzyme was considered to be an independent sensitivity-limiting factor for 5-fluorouracil therapy. The median TS activity and median DPD activity in all specimens including gastric, colorectal, breast, and non-small cell lung cancers tested were 0.041 and 110.1 pmol/mg protein, respectively. We classified each of the type of carcinoma into 4 groups by using the median activity of TS and DPD as the cutoff values: a low TS/low DPD group, high TS/low DPD group, low TS/high DPD group, and high TS/high DPD group. About 50% of the gastric, 47% of the colon, 70% of the breast and 30% of the non-small cell lung cancers had high TS activity, and 60% of the gastric, 40% of the colon, 48% of the breast, and 87% of the lung cancers had high DPD activity. Moreover, breast cancer was characterized by high TS activity and lung cancer by high DPD activity as compared with gastric and colon cancers, and their high activity levels may influence to the effectiveness of 5-fluorouracil against cancers of these organs. The results for expression of TS and DPD in clinically dissected tumors would be useful to estimate the efficacy of 5-fluorouracil in the treatment of cancer patients.  相似文献   
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