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21.
探讨用于小儿放射检查的安全、有效的麻醉方法。选择60例1岁~8岁ASAⅠ-Ⅱ级小儿,分别采用单纯氯胺酮、咪达唑仑复合氯胺酮和异丙酚复合氯胺酮3种麻醉方法。观察3种麻醉方法的效果和安全性以及不良反应,辩证地分析3种麻醉方法的优缺点,思考小儿放射检查的合适的麻醉方法。  相似文献   
22.
Evidence has accumulated for information processing deficits in schizophrenia. The functional significance of these deficits is only beginning to be understood. There are indications that these deficits may respond to intervention. Training on deficient functions has been demonstrated to relate to improvements in performance. A treatment program of cognitive rehabilitation is deduced from the literature and induced from clinical experience. The treatment is designed to impact directly on the information processing deficits of schizophrenic patients and indirectly to ameliorate functional deficits.  相似文献   
23.
《医疗事故处理条例》与《民法通则》确定的赔偿范围和标准不一致。通过《医疗事故处理条例》与《民法通则》的对比,提出医疗损害赔偿的三个原则,即全面赔偿原则、限额赔偿原则、衡平赔偿原则,以及建立医疗损害赔偿费用的统一标准,希望对司法实践有所借鉴意义。  相似文献   
24.
电子媒体设备日益流行的同时, 睡眠问题也日趋加重, 主客观研究均发现电子媒体使用会对睡眠产生消极影响.背后的加工机制涉及睡眠置换,唤醒,屏幕光和电磁辐射.可以通过睡眠卫生教育,限制电子媒体使用,屏蔽屏幕蓝光等方式进行干预.未来研究需要从理论机制的整合,因果关系的确定,测量方式的客观化和标准化,使用情况细化和本土化研究方面做努力.  相似文献   
25.
基于法的规范分析,二类疫苗预防接种损害责任的法律关系及性质比较复杂,体现了违约与侵权责任的竞合,兼具一般医疗技术损害责任和医疗产品责任的双重性质,由此导致其损害责任的构成要件、案由选择、法律适用及救济路径也各不相同。二类疫苗预防接种技术损害责任采用过错归责原则,而二类疫苗的产品损害责任适用无过错归责原则,疫苗的产品责任属于不真正连带责任。深入分析二类疫苗损害责任的性质,有助于厘清其损害责任的承担,促进其损害救济体系的完善。  相似文献   
26.
    
The specific movement demands of soccer that are linked to post-match recovery and readiness to train are unclear. Therefore, we examined the relationship between Global Positioning System (GPS) variables and the change (Δ; from baseline) in Creatine Kinase (CK) concentrations and peak power output (PPO; during the countermovement jump) at 24 h and 48 h post-match. Fifteen English Premier League reserve team players were examined over 1–4 matches. Measurements of CK and PPO were taken before (24 h prior to match-play) and after (+24 h and +48 h) each game during which movement demands were quantified using 10 Hz GPS data. High intensity distance covered (r = 0.386, p = 0.029; r = −0.349; p = 0.050), high intensity distance covered⋅min−1 (r = 0.365, p = 0.040; r = −0.364, p = 0.040), high speed running distance (r = 0.363, p = 0.041; r = −0.360, p = 0.043) and the number of sprints⋅min−1 (r = 0.410, p = 0.020; r = −0.368, p = 0.038) were significantly related to ΔCK and ΔPPO at +24 h post-match, respectively. No relationships were observed between any match variables and ΔCK and ΔPPO after +48 h of recovery. These findings highlight that high intensity match activities are related to ΔCK and ΔPPO in the 24 h, but not 48 h, following soccer match-play. Such information is likely of interest to those responsible for the design of soccer player’s training schedules in the days following a match.  相似文献   
27.
    
Tungsten (W) is cited as a candidate first-wall material in fusion reactors owing to its outstanding thermal properties and erosion resistance. An important issue is that the energetic isotopes of hydrogen, tritium (T) and deuterium (D) and helium (He) particles damage the surface of W in fusion reactors. He particles cause more notable damage than D or T because the binding energy of defects and He is larger than that of defects and D or T. In this study, well-annealed W specimens were implanted with 5 keV He ions at room temperature and irradiation dosages of 1.0 × 1020 and 2.5 × 1021 ions/m2. Then, thermal desorption spectroscopy analysis was performed by heating the samples to 1973 K at a ramping rate of 0.5 K/s. Thermal desorption of He in the sample irradiated with a low dosage occurred at 1400 and 1960 K, whereas that in the sample irradiated with a high dosage occurred at 740, 1050 and 1500 K. According to the microstructures observed using transmission electron microscopy, both peaks in the former case were attributed to He de-trapping from irradiation to nduced helium-vacancy clusters of different sizes, whereas the peaks in the latter case were attributed to He de-trapping from surface defects, irradiation-induced dislocation loops and tiny helium-vacancy clusters, respectively.  相似文献   
28.
    
At the synchrotron facility, Super Photon Ring – 8 GeV, in-situ X-ray diffraction during tensile deformation was conducted on ultrafine-grained Cu with a grain size of about 300 nm fabricated by equal-channel angular pressing. The diffraction profile was observed with the time resolution of about 1 s using multiple MYTHEN detectors, and the diffraction angle and the full-width at half-maximum of some Bragg peaks were determined using the pseudo-Voigt function. From the analysis of Bragg peaks, it was found out that there are microscopically three regions; elastic, plastic and transition regions. The 0.2% proof stress obtained from the stress–strain curve locates within the microscopic transition region. Microstrain was evaluated using the Williamson–Hall method and the dislocation density was also obtained from the microstrain. The dislocation density starts increasing before 0.2% proof stress, which is associated with dislocation bow-out and emission from grain boundaries. The Taylor relationship seems to be still satisfied after 0.2% proof stress.  相似文献   
29.
    
Helium retention in metals is related to their atomic structure and the type of defects they contain. In order to investigate the dependence of helium retention on structure, amorphous Fe79B16Si5 and crystalline FeBSi alloys were irradiated by helium ions at room temperature. In the crystalline alloy irradiated with 5 keV He+ ions, three types of helium trapping sites were found: surface defects produced by the irradiation, interstitial-type dislocation loops, and voids. Although these defects did not exist in the amorphous FeBSi alloy, we did observe thermal desorption peaks related to all three types. In addition, helium was released during the crystallization of amorphous FeBSi that had been irradiated by He+ ions.  相似文献   
30.
Prismatic dislocation loops are the primary manifestation of radiation damage in crystals, and contribute to the phenomenon of radiation embrittlement. This undesirable effect, most serious for materials used in high-dose environments such as next-generation fission and future fusion reactors, results from the strong interaction between gliding dislocations, the carriers of plasticity, with the population of radiation-induced prismatic loops. Ferritic–martensitic steels, the most promising candidate materials for future high-dose applications, are based on iron and are known to become highly elastically-anisotropic at the high temperatures (>500°C) at which they must operate. In this article, we develop a novel modelling approach based on anisotropic elasticity theory to predict the shapes of prismatic loops in anisotropic crystals, paying particular attention to the technologically important case of α-iron. The results are compared with transmission electron microscope observations of the damage structure sustained by ultra-high-purity iron irradiated to a dose of approximately two displacements per atom.  相似文献   
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