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排序方式: 共有1402条查询结果,搜索用时 15 毫秒
71.
NK Suri 《Canadian Metallurgical Quarterly》1997,74(4):242-248
Recent studies indicate beneficial effects of androgen depletion in male mice, before trauma-hemorrhage on cell-mediated immunity following soft-tissue trauma and hemorrhagic shock. Nonetheless, it remains unknown whether androgen receptor blockade following the insult has any salutary effects. To study this, male C3H/HeN mice were either sham-operated or subjected to soft-tissue trauma (i.e., 2.5 cm midline laparotomy) followed by hemorrhagic shock (blood pressure 35 +/- 5 mmHg for 90 min) and then adequately resuscitated (shed blood and lactated Ringer's). Immediately after the completion of resuscitation, as well as 24 and 48 h thereafter, the animals received either vehicle, 10 mg/kg body weight (BW) flutamide or 25 mg/kg BW flutamide subcutaneously. At 72 h after resuscitation, all animals were killed. The spleens and peritoneal macrophages (M phi) were then harvested and cultures established to determine IL-2 and IL-3 release, splenocyte proliferative capacity, as well as splenic and peritoneal M phi IL-1 release. Moreover, plasma testosterone and corticosterone levels were measured. Our results indicate that trauma-hemorrhage resulted in significant depression of splenocyte and M phi functions in vehicle-treated and animals receiving 10 mg/kg BW flutamide. Treatment with 25 mg/kg BW flutamide following trauma-hemorrhage, however, resulted in levels of cytokine release which were comparable with those found in sham-operated animals. No significant alterations in plasma corticosterone and testosterone levels were observed in any of the experimental groups. These findings indicate that short-term therapy of males with the androgen receptor blocker, flutamide at 25 mg/kg BW, following trauma-hemorrhage has protective effects on immune functions. This protective effect is dose dependent, since 10 mg/kg BW flutamide did not produce significant salutary effects. Thus, flutamide represents a novel and safe agent for improving the depressed functions in male trauma patients suffering severe blood loss. 相似文献
72.
73.
Diuron in both, acute (340 and 170 mg/kg body wt) and chronic (3400 ppm) doses induced dominant lethal mutations in male Swiss albino mice. The results suggest that diuron is mutagenic in dominant lethal test system. 相似文献
74.
Nakano H. Yoshizawa A. Yamauchi J. 《Antennas and Propagation, IEEE Transactions on》1985,33(4):409-415
A crossed-wire scatterer has the wires displaced in the backscattering direction, and is able to scatter an incident wave of circular polarization in such a way that the backscattering wave has the same rotational sense as that of the incident wave. The radiation performance of the scatterer is improved by bending the horizontal and the vertical wires. Arrays consisting of crossed-wire scatterers are constructed and the backscattering cross sections (BSCS's) are calculated. It is revealed that the increase in the current amplitude due to the mutual effects among the array elements contributes to enhancement in the BSCS. It is also shown that a maximum value of the BSCS of an array of3 times 3 bent crossed-wire scatterers is 1.8 times as large as that of a dihedral corner reflector which has the same aperture area. The BSCS's as a function of the angle of incidence are presented with experimental results at a frequency of 9.375 GHz. 相似文献
75.
An AlGaAs/GaAs HBT direct-coupled amplifier has been designed and its characteristics described for the first time. The amplifier consists of two HBTs and three resistors without level-shift diodes. A superior amplifier performance of 11 dB gain with a 4 GHz bandwidth was obtained. 相似文献
76.
There are many cases when a neural-network-based system must memorize some new patterns incrementally. However, if the network learns the new patterns only by referring to them, it probably forgets old memorized patterns, since parameters in the network usually correlate not only to the old memories but also to the new patterns. A certain way to avoid the loss of memories is to learn the new patterns with all memorized patterns. It needs, however, a large computational power. To solve this problem, we propose incremental learning methods with retrieval of interfered patterns (ILRI). In these methods, the system employs a modified version of a resource allocating network (RAN) which is one variation of a generalized radial basis function (GRBF). In ILRI, the RAN learns new patterns with a relearning of a few number of retrieved past patterns that are interfered with the incremental learning. We construct ILRI in two steps. In the first step, we construct a system which searches the interfered patterns from past input patterns stored in a database. In the second step, we improve the first system in such a way that the system does not need the database. In this case, the system regenerates the input patterns approximately in a random manner. The simulation results show that these two systems have almost the same ability, and the generalization ability is higher than other similar systems using neural networks and k-nearest neighbors. 相似文献
77.
The purpose of this study was to characterize the oxide scales formed on various Cr-Si-Ni compacts at 1273 K in air and H2O-containing atmosphere by TEM. It was found that CrSi2-(5-20)mass%Ni compacts form double layer scales, consisting of an outer Cr2O3 layer and an inner SiO2 layer. The oxide scale changed from SiO2- to Cr2O3-based scale with an increase in the Ni concentration. However, it was observed that the oxide scale formed in H2O-containing atmospheres showed local SiO2 growth into the substrate. This result suggests that the inward oxidant diffusion promotes the local growth of SiO2 in the H2O-containing atmospheres. 相似文献
78.
Md. Nazrul Islam Keisuke Ando Hidefumi Yamauchi Nobuaki Hattori 《Holz als Roh- und Werkstoff》2009,67(2):129-133
Penetration of liquid by passive impregnation method for Douglas-fir (Pseudotsuga menziesii Franco), sugi (Cryptomeria japonica D. Don) and Japanese larch (Larix leptolepis Gordon) was studied. Effects of initial moisture content of sugi (16, 43 and 70% moisture content) on liquid penetration were also studied. Dried Douglas-fir (mc=14%) and sugi (mc=16%), and green Japanese larch (mc=45%) and sugi (mc=70%) were treated by passive impregnation method for penetration analysis. It was observed that dried sugi had the highest level of liquid penetration both in length (170 mm) and width (8 mm) for all measured sections followed by green sugi, green Japanese larch and dried Douglas-fir. In case of different initial moisture content, the highest absorption (624 kg/m3) and penetration (maximum 87 and 96% at cross and longitudinal surfaces, respectively) was observed for sugi having the lowest initial moisture content under the same passive impregnation conditions. Absorption and penetration decreased with the increase of initial moisture content for sugi. These results could help in designing incising pattern and density, as well as solving the problems related to high initial moisture content of wood for passive impregnation. 相似文献
79.
Measurements of the V–I characteristics of a solid polymer electrolytic (SPE) dehumidifier were done using a modified SPE
dehumidifier with four electrodes which included two electrodes to carry the main current and the other two electrodes to
measure the voltages applied to the electrical double layer, which are the boundary voltages between the electrodes and the
SPE membrane. The measured results were analyzed using the Butler-Volmer equation to examine the validity of the measurements.
The current flowing in the dehumidifier is produced by the decomposition of water near the anode. Therefore, under a steady-state
condition, the current should be proportional to the supply rate of water to the anode. On the other hand, a two-layer model
for the SPE dehumidifier presented in our previous article showed that the current flowing in the dehumidifier was roughly
proportional to the water content in the vicinity of the anode. These results were introduced for interpretation of the V–I
measurements of the SPE dehumidifier. It was concluded that the dehumidifier current was expressed in the form of a Butler-Volmer
equation as a function of the electrode boundary voltages which were the voltages across the boundary between the electrodes
and the SPE membrane. An experimental formula for the current under a steady-state condition was developed as a function of
the water content near the anode and the boundary voltages. 相似文献
80.
Both President Peter Reynolds and Secretary General Glenn Stout attended the IWRA Regional Seminar on Water Quality and its Management in New Delhi, India on December 10–11, 1985. Over 100 members and fellow water scientists and administrators attended. Leading Indian water authorities participated in the program. We reproduce here the inaugural address by Shri B. Shankaranand, Union Minister for Water Resources, and a summary of the Conclusions and Recommendations. 相似文献