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排序方式: 共有4557条查询结果,搜索用时 0 毫秒
941.
S Teraoka Y Nakagawa M Nakamura S Hirotani T Tohjinbara O Tomonaga T Babazono H Ohgawara Y Iwamoto I Nakajima S Fuchinoue T Agishi 《Canadian Metallurgical Quarterly》1998,30(2):301-303
In adult rats, oxytocin (OT) has been shown to reduce the intake of both food and fluids, and oxytocinergic cells are activated by gastric distension and administration of the intestinal peptide cholecystokinin (CCK-8). These and other findings indicate that OT can play a role in inhibiting ingestion under some conditions. A previous study has shown, however, that oxytocinergic cells are unresponsive to CCK-8 in 2-day-old rats. We report here that OT is elevated in the plasma of 10-day-old rats after induction of gastric distension with both mother's milk and saline. These results indicate that the vagal-hypothalamic axis becomes mature between 2- and 10-days of age in infant rats. 相似文献
942.
Y Kanamori J Kigawa Y Minagawa T Irie T Oishi M Shimada M Takahashi T Nakamura K Sato N Terakawa 《Canadian Metallurgical Quarterly》1998,34(11):1802-1806
A new recombinant adenovirus carrying a wild-type p53 gene (AxCAp53) was developed and the combination effect of p53 gene transfer and cis-diamminedichloroplatinum (II) (CDDP) was examined in an ovarian cancer cell line, SK-OV-3, with deletion of the p53 gene. AxCAp53 showed a high efficiency of gene transduction and increased sensitivity to CDDP in the SK-OV-3 cells. It was found that the sensitivity of the cells to CDDP correlated with the amount of infectious units of virus per cell of AxCAp53 which correlated with p53 protein expression. The results suggest that the combination of CDDP and AxCAp53 may be a potential strategy for the therapy of CDDP-resistant ovarian cancer. 相似文献
943.
BACKGROUND: As a result of the pending ban on chlorofluorocarbon production, the non-chlorofluorocarbon propellant 1,1,1,2-tetrafluoroethane (HFA-134a) is being evaluated as a replacement for CFCs in metered-dose inhalers. OBJECTIVES: This cumulative dose response study compared the safety and bronchodilator efficacy of 16 cumulative inhalations of albuterol sulfate in an HFA-134a, CFC-free propellant system (108 microg of albuterol sulfate, equivalent to 90 microg of albuterol base) with that of equivalent doses of albuterol in a conventional CFC propellant system. METHODS: Twenty-two patients with at least a 12-month history of stable asthma, who were currently taken an inhaled beta-adrenergic bronchodilator, and who had a FEV1 between 40% and 80% of predicted, were enrolled in this randomized, modified-blind, two-period crossover study. One, 1, 2, 4, and 8 inhalations of study drug were self-administered at 30-minute intervals, resulting in 16 cumulative inhalations. Pulmonary function and safety measures were assessed after each dosing interval. RESULTS: A significant dose response was found for HFA-134a albuterol sulfate and CFC albuterol with regard to changes in FEV1, serum potassium, heart rate, and blood pressure after 16 cumulative inhalations. No significant differences were demonstrated between HFA-134a albuterol sulfate and CFC albuterol for any FEV1 or safety parameter at any cumulative dose level. No clinically meaningful laboratory or physical examination abnormalities were found with administration of either HFA-134a albuterol sulfate or CFC albuterol. CONCLUSIONS: HFA-134a albuterol sulfate provides bronchodilation comparable to CFC albuterol and has a similar safety profile. 相似文献
944.
Pulse CVI of porous carbon 总被引:1,自引:0,他引:1
945.
T. Nakamura Y. Uwamino K. Sato Y. Furuta S. Tanaka S. Ban H. Hirayama T. Kosako K. Kawachi Y. Nishihara 《Atomic Data and Nuclear Data Tables》1985,32(3):471-501
The literature on neutron and photon production from thick targets bombarded by charged particles has been surveyed. The survey covers fourteen journals and some internal reports and conference proceedings, mainly from 1965 up to June 1984. For each paper, applicable information is listed on type and energy of the projectile, the accelerator used, composition and thickness of the target, the experimental method, the calculation, and the quantities obtained. The references on neutron and on photon production are accessed through two indices which list the available projectile-target combinations and the projectile energy range. 相似文献
946.
Homma N. Nakamura T. Hayashida T. Matsumoto M. Nakazato K. Onai T. Tamaki Y. Namba M. Sagara K. Ikeda K. 《Electron Devices, IEEE Transactions on》1988,35(12):2094-2100
A soft-error-immune switched-load-resistor memory cell especially suitable for ultrahigh-speed bipolar RAM has been developed. The memory cell is composed of upward sidewall base contact structure (SICOS) transistors and shielded Schottky-barrier diodes (SBDs). Alpha-particle-induced noise charges generated in the p--substrate are completely shielded by n+-buried layers of the transistors and the SBDs. Only the noise charges generated in the transistors or the SBDs active regions are gathered in the collectors of the memory cell. The maximum collected noise charge is reduced to a quarter of that of conventional memory cells using SICOS downward transistors and conventional SBDs. Experiments show that this reduction of the collected noise charge increases soft-error immunity to more than 105 times that of conventional memory cells. This result using hot radiation sources does not directly correspond to the real soft-error rate in the field, but demonstrates the realization of an ultrahigh-speed soft-error-immune memory cell 相似文献
947.
Hirayama Y. Furuyama H. Morinaga M. Suzuki N. Kushibe M. Eguchi K. Nakamura M. 《Electronics letters》1988,24(8):452-454
A self-aligning (SA) process technique to fabricate constricted mesa (CM) lasers is proposed. The controllability of GaInAsP active region volume and InP lateral confining layer widths were greatly improved. Lasers grown entirely by metalorganic chemical vapour deposition (MOCVD) showed very small variation in threshold currents ( I th=15.2±1.1 mA) and in stray junction capacitances (C =1.62±0.08 pF). A record bandwidth of 10 GHz in the 1.5 μm-wavelength region was demonstrated 相似文献
948.
Mandler George; Nakamura Yoshio; Van Zandt Billie J. 《Canadian Metallurgical Quarterly》1987,13(4):646
The repeated exposure of unmasked irregular geometric shapes for very brief durations (1 or 2 ms) has been shown to generate preferences as well as judgments of familiarity for the previously exposed shapes. At the same time these stimuli are not recognized as having been presented. Such exposure also leads to judgments of brightness and darkness independent of stimulus intensity, and it is dependent on the use of unmasked stimuli. This effect is nonspecific, in contrast to stimulus-specific effects with masked stimuli, and it is not restricted to affective judgments. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
949.
K Oda H Asao M Higuchi N Tanaka S Moffatt M Nakamura K Tabayashi K Sugamura 《Canadian Metallurgical Quarterly》1997,9(9):1303-1310
Our previous study demonstrated that IL-2 suppressed growth of human T cell lines, in which the suppression was observed with members among HTLV-I-infected T cell lines independent of IL-2 for growth. In this study, we examined the molecular mechanism of IL-2-induced growth suppression with two HTLV-I-infected T cell lines; TL-OmI expressing endogenously three subunits, i.e. alpha, beta and gamma chains, of the IL-2 receptor, and an MT-1 transfectant expressing the endogenous alpha and gamma chains and exogenous beta chain. Our analysis revealed that IL-2 induced apoptosis in both T cell lines. Experiments with inhibitors for the proteases responsible for apoptosis signals showed that caspase 1 (IL-1 beta-converting enzyme) was not involved in apoptosis induced by IL-2. Other MT-1 sublines introduced with mutant beta chains demonstrated that IL-2-induced apoptosis required signals from both the serine-rich (S) region and acidic (A) region of the IL-2 receptor beta chain, which are essential but not critical for IL-2-mediated cell growth respectively. Collectively, IL-2 functions not only on growth promotion and prevention of apoptosis but also on induction of apoptosis, which may be implicated in physiological regulation of immune reactions by controlling growth and activation of T cells. 相似文献
950.
STUDY OBJECTIVES: To evaluate renal function during and after hypotensive anesthesia with sevoflurane compared with isoflurane in the clinical setting. DESIGN: Randomized, prospective study. SETTING: Inpatient surgery at Rosai Hospital. PATIENTS: 26 ASA physical status I and II patients scheduled for orthopedic surgery. INTERVENTIONS: Patients received isoflurane, nitrous oxide (N2O), and fentanyl (Group I = isoflurane group; n = 13) or sevoflurane, N2O, and fentanyl (Group S = sevoflurane group; n = 13). Controlled hypotension was induced with either isoflurane or sevoflurane to maintain mean arterial pressure at 60 mmHg for 120 minutes. MEASUREMENTS AND MAIN RESULTS: Measurements included serum inorganic fluoride (previously speculated to influence renal function), creatinine clearance (CCr; to assess renal glomerular function), urinary N-acetyl-beta-D-glucosaminidase (NAG; to assess renal tubular function), blood urea nitrogen (BUN), and serum creatinine (as clinical renal function indices). Serum fluoride, CCr, and NAG were measured before hypotension, 60 minutes, and 120 minutes after the start of hypotension, 30 minutes after recovery of normotension, and on the first postoperative day. BUN and serum creatinine were measured preoperatively and on the third and seventh postoperative days. Minimum alveolar concentration times hour was 3.6 +/- 1.8 in Group I and 4.0 +/- 0.7 in Group S. In both groups, BUN and serum creatinine did not change, and CCr significantly decreased after the start of hypotension. In Group I, serum fluoride and NAG did not change. In Group S, serum fluoride significantly increased after the start of hypotension compared with prehypotension values and compared with Group I values. In addition, NAG significantly increased at 120 minutes after the start of hypotension and at 30 minutes after recovery of normotension, but returned to prehypotension values on the first postoperative day. CONCLUSIONS: Two hours of hypotensive anesthesia with sevoflurane under 5 L/min total gas flow in patients having no preoperative renal dysfunction transiently increased NAG, which is consistent with a temporary, reversible disturbance of renal tubular function. 相似文献