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1.
Studies using magnetic resonance spectroscopy in human volunteers to evaluate their livers in vivo and to analyze their blood in vitro suggest that there are measurable amounts of silicon compounds in the blood of some women with implants and that there is migration of silicone to other organs such as the liver.  相似文献   
2.
目的:观察藏药四臣止咳颗粒剂的药效作用及机理。方法:采用咳嗽、炎症、发热等动物模型观察其止咳、抗炎、解热作用。结果:该制剂在6.7g生药/kg、13.4g生药/kg、26.8g生药/kg剂量下,各剂量组均能显著的抑制浓氨水诱发的小鼠咳嗽(P〈0.01),中、大剂量组均能显著的抑制二氧化硫诱发的小鼠咳嗽(P〈0.01);在8.14g生药/kg、16.28g生药/kg剂量下能显著的抑制枸橼酸诱发的豚鼠咳嗽(P〈0.01),对大鼠和小鼠的急性炎症反应有抗炎作用,对家兔发热有轻度的解热作用。结论:证实了四臣止咳颗粒剂的止咳作用及其机理。  相似文献   
3.
目的:类风湿关节炎(Rheumatoid Arthritis,RA)是一种累及全身小关节的自身免疫性疾病。前期研究发现,充足的淋巴回流功能有利于RA的恢复。本文主要探讨二陈加桃红四物汤治疗本病的疗效及其对淋巴管回流功能的影响。方法:本研究采用10周龄TNF转基因(TNF-Tg)小鼠为模型,以二陈加桃红四物汤灌胃治疗12周,并选取同窝野生型小鼠作对照,采用Micro-CT观测小鼠的踝关节骨量,采用近红外-吲哚菁绿系统检测小鼠下肢淋巴管功能。结果:Micro-CT三维成像显示,与对照组相比,TNF-Tg组可见明显的骨质破坏,踝关节结构严重受损。二陈加桃红四物汤治疗后,骨结构得到了一定程度的保护。淋巴管回流功能检测显示,与对照组相比,TNF-Tg组的淋巴管清除率明显下降;与TNF-Tg组相比,二陈加四物汤可促使受损的淋巴功能恢复。与对照组小鼠相比,TNF-Tg组的Pulse值明显下降,与TNF-Tg组相比,二陈加桃红四物汤可促进Pulse值明显升高。结论:二陈加桃红四物汤可以有效促进TNF转基因小鼠模型下肢的淋巴回流功能,从而缓解关节炎症,保护骨组织免受侵蚀。  相似文献   
4.
基于成熟的脉诊、舌诊信息提取与识别的关键技术,集成便携式辅助诊疗系统突出脉诊、舌诊在中医诊疗中的重要作用,并融合其他四诊信息,实现自动辨证处方的临床辅助诊疗功能。便携式辅助诊疗系统体现了"四诊合参"的中医辨证诊断理念,其便携化、智能化、人性化的特点贴合临床实际,为脉诊、舌诊研究成果的推广应用奠定了完备的条件。  相似文献   
5.
Abstract

Background. The standard frequently-sampled intravenous glucose tolerance test (FSIVGTT) is an alternative procedure to the clamp technique for estimating the insulin sensitivity (Si) parameter. The goal of this study was to compare Si in lean and overweight individuals in addition to assessing intra-individual reproducibility using two different protocols and updated software. Methods. FSIVGTT was carried out in 14 lean (BMI ≤ 25 kg/m2) and 14 overweight (BMI>25 kg/m2) subjects using two different protocols; full (29 samples) and short (12 samples). For reproducibility assessment four normal subjects (triplicate on three and twice on one) were recruited to undergo the same procedure at 1-week intervals. Data analysis was performed using COMAL and Minmod Millennium software. Results. Mean Si (10?4min?1[pmol/l]?1) values were significantly different between lean and overweight subjects (p < 0.001) but not between the two protocols using both software packages. For the full and short protocols, Si values were more closely related in lean versus overweight subjects using either COMAL (r = 0.98, p < 0.001), (r = 0.89, p < 0.001) or Minmod Millennium (r = 0.99, p < 0.001), (r = 0.85, p < 0.001) software respectively. The intra-individual reproducibility (%CV) of Si (COMAL) in full versus short protocol was 18.3 ± 11.1% and 13.7 ± 1.9% respectively. Reproducibility values for Si (Minmod Millenium) in full versus short protocols were 14.3 ± 3.8 and 14.9 ± 1.9% respectively. Conclusions. Si can be assessed accurately by a short protocol FSIVGTT in normal individuals. The short protocol may give less acceptable results for insulin sensitivity in individuals who have normal glucose tolerance but high BMI.  相似文献   
6.
Single crystal silicon solar cells are still predominant in the market due to the abundance of silicon on earth and their acceptable efficiency. Different solar-cell structures of single crystalline Si have been investigated to boost efficiency; the heterojunction with intrinsic thin layer (HIT) structure is currently the leading technology. The record efficiency values of state-of-the art HIT solar cells have always been based on n-type single-crystalline Si wafers. Improving the efficiency of cells based on p-type single-crystalline Si wafers could provide broader options for the development of HIT solar cells. In this study, we varied the thickness of intrinsic hydrogenated amorphous Si layer to improve the efficiency of HIT solar cells on p-type Si wafers.  相似文献   
7.
Al–5Ti–C master alloy was prepared and used to modify hypereutectic Al–20%Si alloy. The microstructure evolution and mechanical properties of hypereutectic Al–20%Si alloy with Al–5Ti–C master alloy additions (0, 0.4, 0.6, 1.0, 1.6 and 2.0 wt%) were investigated. The results show that, Al–5Ti–C master alloy (0.6 wt%, 10 min) can significantly refine both eutectic and primary Si of hypereutectic Al–20%Si alloy. The morphology of the primary Si crystals was significantly refined from a coarse polygonal and star-like shape to a fine polyhedral shape and the grain size of the primary Si was refined from roughly 90–120 μm to 20–50 μm. The eutectic Si phases were modified from a coarse platelet-like/needle-like structure to a fine fibrous structure with discrete particles. The Al–5Ti–C master alloy (0.6 wt%, 30 min) still has a good refinement effect. The ultimate tensile strength (UTS), elongation (El) and Brinell hardness (HB) of Al–20%Si alloy modified by the Al–5Ti–C master alloy (0.6 wt%, 10 min) increased by roughly 65%, 70% and 51%, respectively, due to decreasing the size and changing the morphology on the primary and eutectic Si crystals. The change in mechanical properties corresponds to evolution of the microstructure.  相似文献   
8.
The misfit dislocations and strain fields at a Ge/Si heterostructure interface were investigated experimentally using a combination of high-resolution transmission electron microscopy and quantitative electron micrograph analysis methods. The type of misfit dislocation at the interface was determined to be 60° dislocation and 90° full-edge dislocation. The full-field strains at the Ge/Si heterostructure interface were mapped by using the geometric phase analysis (GPA) and peak pairs analysis (PPA), respectively. The effect of the mask size on the GPA and PPA results was analyzed in detail. For comparison, the theoretical strain fields of the misfit dislocations were also calculated by the Peierls-Nabarro and Foreman dislocation models. The results showed that the optimal mask sizes in GPA and PPA were approximately three tenths and one-tenth of the reciprocal lattice vector, respectively. The Foreman dislocation model with an alterable factor a = 4 can best describe the strain field of the misfit dislocation at the Ge/Si heterostructure interface.  相似文献   
9.
Hypereutectic Al-Si alloys are attractive materials in the fields of electronic packaging and aerospace. A Bi2O3-ZnO-B2O3 system lead-free brazing filler glass was employed to braze hypereutectic Al-50Si alloys in air. The hypereutectic Al-50Si alloys were pre-oxidized and the low-temperature glass powder was flake-shaped in the brazing process. The effects of brazing temperature and time on joints microstructure evolution, resulting mechanical strength, and air tightness were systematically investigated. The results indicated that the maximum shear strength of the joint was 34.49 MPa and leakage rate was 1.0 × 10−10 Pa m3/s at a temperature of 495 °C for 30 min. Crystalline phases, including Bi24B2O39 and Bi2O3, were generated in the glass joint. The formation of a diffusion transition layer with a thickness of 3 μm, including elements of Al, Si, Zn, Bi, Na, and B, was the key to form an effective joint. The elements of Al, Si, and Bi had a short diffusion distance while the elements of Zn, Na, and B diffused in a long way under brazing condition.  相似文献   
10.
We grew epitaxial layers on 4H-silicon carbide (SiC) Si-face substrates with a 1° off-angle. The suppression of 3C-inclusion formation during growth at a high C/Si ratio was investigated, because a growth technique with a high C/Si ratio is needed to decrease residual nitrogen incorporation. 3C inclusions were generated both at the interface between the substrate and epitaxial layer, and during epitaxial growth. 3C-SiC nucleation is proposed to trigger the formation of 3C inclusions. We suppressed 3C-inclusion formation by performing deep in situ etching and using a high C/Si ratio, which removed substrate surface damage and improved the 4H-SiC stability, respectively. The as-grown epitaxial layers had rough surfaces because of step bunching due to the deep in situ etching, but the rough surface became smooth after chemical mechanical polishing treatment. These techniques allow the growth of epitaxial layers with 1° off-angles for a wide range of doping concentrations.  相似文献   
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