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排序方式: 共有792条查询结果,搜索用时 31 毫秒
71.
72.
73.
T Kawakami-Tani E Fukawa H Tanaka Y Abe I Makino 《Canadian Metallurgical Quarterly》1997,46(10):1184-1188
We performed a randomized, open prospective study to determine the effect of 1 alpha-hydroxyvitamin D3 [1 alpha (OH)D3] on hyperthyroidism in patients with untreated Graves' disease. At the time of entry into the study, 30 patients were randomly assigned to receive a daily dose of 30 mg methimazole (MMI) (group A, n = 15) or the same dose of MMI supplemented with 1.5 micrograms 1 alpha (OH)D3 (group B, n = 15). These treatment regimens were continued for 24 weeks, and physicians were allowed to adjust MMI dosage during follow-up visits. Blood samples were collected, and serum concentrations of free triiodothyronine (FT3), free thyroxine (FT4), T3, T4, thyrotropin (TSH), alkaline phosphatase (ALP), and TSH-receptor antibody (TRAb) were determined. During the follow-up periods, all patients became euthyroid. The dose of MMI was not significantly different between these two groups. In contrast, decreases in mean serum FT3 and FT4 levels, as well as in mean serum T3 and T4 levels, were greater in group B. Correspondingly, the reciprocal increase in the mean TSH level was more prominent in group B. Mean TRAb levels did not differ between the two groups. Mean serum ALP levels in group B were significantly lower than in group A at 24 weeks. Thus, we suggest that concomitant administration of 1 alpha (OH)D3 is useful for treating hyperthyroidism in patients with Graves' disease. 相似文献
74.
We studied whether inducers of cell differentiation alone could have cytotoxic effect on the promonocytic U937 and Mono Mac 6 cells in vitro. The cells were incubated with standard differentiating doses of interferon (IFN)-gamma, dibutyryl cAMP (Bt2cAMP) or the phorbol ester phorbol-12-myristate-13-acetate (PMA), with or without lipopolysaccharide (LPS), and both protein synthesis and viability were examined. In both U937 and Mono Mac 6 cells the incorporation of [3H]leucine was significantly reduced after PMA plus LPS stimulation, but not after IFN-gamma stimulation, when compared with controls. For U937 cells there was also reduced incorporation after Bt2cAMP stimulation. Trypan blue exclusion experiments and the number of cells remaining in the cultures indicated that Bt2cAMP-, PMA- and/or LPS-stimulated, but not IFN-gamma-stimulated, cells were less viable than unstimulated U937 or Mono Mac 6 cells. The results suggest that Bt2cAMP, PMA and LPS, but not IFN-gamma, are cytotoxic towards promonocytic cancer cell lines in vitro. 相似文献
75.
Atom-order void formation in a defective crystalline material is studied by using molecular dynamics method (MD). Infinite
long cylinder, which is constructed with nickel atoms with a line of vacancies, is subjected to multiaxial tensile strain
field by moving periodic boundary and the atoms on the outer surface of the cylinder. When the load exceeds a critical value,
sudden appearance of the void is observed and it develops rapidly. The developed void does not disappear by only unloading
and relaxation, in spite of the system with the void has higher potential energy than that without void. The biaxial or the
triaxial load is necessary to the atom order void formation. Moreover, the results by the MD simulations are compared with
theoretical solution for nonlinear elastic solid.
Received 26 August 1999 相似文献
76.
77.
The effect of pre-operative radio-chemotherapy (RCT) has been examined in a total of 15 oral squamous cell carcinomas (SCCs), in terms of apoptosis (cell loss) and proliferation. All the patients received pre-operative radiation at a dosage of 30 or 40 Gy, as well as anticancer agents including tagaful (FT), 5-fluorouracil (5-FU), bleomycin (BLM) and peplomycin (PEP). Surgical specimens were obtained before and after RCT, and serial sections were prepared for immunohistochemistry for p53 oncoprotein and Ki-67 antigen, as well as for terminal deoxynucleotidyl transferase (TdT)-mediated dUTP-biotin nick end labeling (TUNEL). TUNEL indices (TI; percentage of TUNEL-positive cells in the tumor cells) before and after RCT were 1.2+/-1.1 and 4.7+/-2.9 in the nine well-differentiated oral SCCs, and 1.0+/-0.7 and 3.9+/-2.1 in the six poorly differentiated SCCs, respectively. Similarly, Ki-67 indices (KI; percentage of Ki-67 antigen-positive cells in tumor cells) before and after RCT were 31.1+/-14.2 and 15.8+/-11.1 in the former, and 37.1+/-7.8 and 8.7+/- 13.4 in the latter, respectively. Thus, pre-operative RCT enhanced apoptotic cell death and abated proliferative activity significantly (P<0.05), regardless of histological differentiation. Enhancement of apoptosis was more prominent in the group treated with FT or 5-FU than with BLM or PEP. Oral SCC with >20% of nuclear p53-positive tumor cells was noted in six cases. Enhanced TI and abadement of KI did not differ among the p53-positive and -negative tumors. 相似文献
78.
Analysis of close-contact melting for octadecane and ice inside isothermally heated horizontal rectangular capsule 总被引:11,自引:0,他引:11
T. Hirata Y. Makino Y. Kaneko 《International Journal of Heat and Mass Transfer》1991,34(12):3097-3106
Close-contact melting characteristics of phase change materials (PCM) inside horizontal rectangular capsules are examined experimentally. The capsules are heated isothermally and three kinds of aspect ratios (H/W = 3, 1 and 1/3) are provided. Octadecane and ice are used, respectively, as PCM. A method of analysis applying Nusselt's liquid film theory to the close-contact melting heat transfer in the rectangular capsule is presented. The analytical results show good agreement with the experimental data. For the melting of ice, it is found that the effect of natural convection resulting from density inversion of water at 4°C becomes significant for large Stefan numbers. 相似文献
79.
Noda M. Matsue S. Sakai M. Sumitani K. Nakano H. Oku T. Makino H. Nishitani K. Otsubo M. 《Electron Devices, IEEE Transactions on》1992,39(3):494-499
The authors have realized 16-kb SRAMs with maximum address access time of less than 5 ns and typical power dissipation of less than 2 W at temperatures ranging from 25°C to 100°C. For the RAMs, they have developed a triple-level Au-based interconnection technology that reduces the wiring length and chip size of the SRAM so as to achieve high speed and high yield. Consequently, the wiring length and chip size are reduced to 69% and 58%, respectively, of those obtained by in previous work. The authors experimentally compared the delay time incurred by double-level interconnection and that by triple-level interconnection. This ratio is found to agree well with the simulated one by a model with distributed RC delay. After successfully suppressing Au hillock generation by lowering the process temperature, yield per wafer of 10% is obtained 相似文献
80.
K Uozumi N Ohno K Nakahara T Makino A Utsunomiya S Hanada T Arima 《Canadian Metallurgical Quarterly》1997,77(2):204-210
Differences in the responses of an elderly biracial group of cognitively normal subjects to a 15-item short version of the Boston Naming Test developed for the Consortium to Establish a Registry for Alzheimer's Disease (CERAD) were examined. The subjects consisted of 103 Whites and 136 African Americans who were 70 years of age and older and living in a five-county urban and rural area of North Carolina. They were drawn from the Duke University site of the Established Populations for Epidemiologic Studies of the Elderly (EPESE). All were cognitively normal. With gender, years of education, and age controlled, White subjects performed significantly better than did African American subjects. The items in this test were selected to represent words with a high, medium, and low frequency of occurrence in English. They did not, however, show the expected gradation for either racial group. Medium and low frequency items were of comparable difficulty for the two races. Hierarchical ordering of difficulty would be improved with minor rearrangement of items. 相似文献