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51.
冲击波研究长期以来用于解决超音速飞行、宇宙飞船重返大气层等相关的高速气体动力学问题.近30年来,冲击波技术成功地应用于医学领域.本文从阐述体外冲击波碎石机的工作原理开始,对体外冲击波碎除肾结石和尿道结石的作用机制(如应力作用、空化效应)进行评述;在此基础上,重点介绍了冲击波治疗骨不连、假关节、肩周炎、网球肘及其他骨科疾病的临床疗效.通过认识气泡崩裂产生的微型水喷射的特点,综述了水中微爆炸、激光聚焦产生的微型水喷射和微型冲击波进行血运重建的理论和方法;通过认识基于冲击波的DNA/药物的定向转运技术,综述了液态DNA转运、粉末状药物转运、分子转移入胞的实验装置和实验结果.此外,还介绍了冲击波在兽医学中用于治疗马、犬等动物的跟腱、韧带和骨的损伤的疗效.最后,展望了今后值得研究的几个领域:冲击波的新波源、冲击波治疗的新设备、冲击波技术在脑血栓血运重建和癌症治疗中的应用.   相似文献   
52.
为了实现低附带弹药金属颗粒定向可控加载,研制了采用爆轰方式驱动低附带弹药金属颗粒的发射装置,并进行了不同尺寸钨球颗粒与不同装药比的发射实验。运用高速摄影与高速红外摄影捕捉爆轰驱动过程中颗粒抛撒分布和速度,并采用CT断层扫描和三维图像重建再现了颗粒在肥皂靶中的三维空间分布。实验结果揭示了爆轰驱动下颗粒加速、减速和散落3个阶段的特征。钨球颗粒速度均值范围为689.84~889.14 m/s,最大侵彻深度为65.23~167.35 mm,颗粒加载上靶率在30%以上。发射装置中金属颗粒/装药质量比可调,能重复使用。采用肥皂靶、高速摄影、高速红外相结合的测试方法有效可行,CT图像重建用于终点弹道参数判读能提高结果分析精度。以上结果可为研究低附带弹药对生物目标的毁伤效应、致伤机理和生物损伤判定与救治提供有效可行的技术与方法。  相似文献   
53.
A novel series of quaternary ammonium cationic derivatives based on tetrapyridyl-porphyrin was synthesized.All the compounds were evaluated for their in vitro antibacterial activities against S.aureus,E.coli and P.aeruginosa,and antifungal activities against C.albicans,where microorganisms were exposed and unexposed to the irradiation.The results revealed that some of these compounds,especially,3a and 4a displayed satisfactory antibacterial activity against Gram-positive bacteria S.aureus and moderate an...  相似文献   
54.
本文回顾性分析19例经病理证实为WHO Ⅱ-Ⅲ级且具有T2/FLAIR错配征的脑胶质瘤患者.从患者的影像数据中提取肿瘤区整体特征和错配区影像参数进行定量分析,探讨T2/FLAIR错配征在评价异柠檬酸脱氢酶(IDH)突变伴1p/19q未联合缺失型(IDHMUT/1p/19q+)较低级别胶质瘤(LGG)的诊断效能.本研究表明,整体及部分T2/FLAIR错配征可作为预测IDHMUT/1p/19q+ LGG的影像标志物.肿瘤区整体影像特征联合错配区定量参数有助于提高对IDHMUT/1p/19q+ LGG的诊断效能.  相似文献   
55.
Online object tracking is a challenging problem as it entails learning an effective model to account for appearance change caused by intrinsic and extrinsic factors. In this paper, we propose a novel online object tracking with guided image filter for accurate and robust night fusion image tracking. Firstly, frame difference is applied to produce the coarse target, which helps to generate observation models. Under the restriction of these models and local source image, guided filter generates sufficient and accurate foreground target. Then accurate boundaries of the target can be extracted from detection results. Finally timely updating for observation models help to avoid tracking shift. Both qualitative and quantitative evaluations on challenging image sequences demonstrate that the proposed tracking algorithm performs favorably against several state-of-art methods.  相似文献   
56.
采用电感耦合等离子体质谱仪测定煤矸石中的铀含量.试验对比研究了试样的3种前处理方法,并对仪器条件进行了优化,建立了相应的电感耦合等离子体质谱仪的测定方法.方法的检出限为0.05μg/g,相对标准偏差小于4%,加标回收率在97%~103%之间.  相似文献   
57.
We report on a new kind of non-covalent multi-label electrochemical immunoassay that was applied to simultaneously quantify the tumor markers CA15-3 and CA19-9. The method employs a nanohybrid composed of an ionomer and conductive titanium dioxide nanoparticles that act as a matrix support for the antibodies. The two antibodies (anti-CA153 and anti-CA199) were labeled (a) with a cobaltous dipyridine complex, and (b) with methylene blue. Labeling is based on cation-exchange interaction rather than on covalent conjugation. The redox potentials of the two labels are separated by an interval of 0.3 V. The resulting sandwich-type immunosensor was read out by differential pulse voltammetry. The potential sites and currents of the two redox probes reflect the concentration of the two analytes. The two analytes were determined with a detection limit of 1.6 U?mL?1 for CA19-9, and of 0.3 U?mL?1 for CA15-3.
Figure
A new non-covalent multi-label electrochemical immunoassay was applied to simultaneously quantify dual tumor markers. DPV performed the identification and quantification of dual analytes on same electrode surface.  相似文献   
58.
A signal‐enhanced label‐free electrochemical immunosensor was constructed by the employment of Prussian blue doped silica dioxide (PB‐SiO2) nanocomposite. At first, PB‐SiO2 nanocomposite which was produced by using a microemulsion method was used to obtain a nanostructural monolayer on a glassy carbon electrode (GCE) surface. Next amino‐functionalized interface were prepared by self‐assembling 3‐aminopropyltriethoxy silane (APTES) on the PB‐SiO2 nanoparticle surface. Then chitosan stabled gold nanoparticle (CS‐nanoAu) was subsequently attached, while the entire surface was finally loaded with neuron‐specific enolase antibody (anti‐NSE) via the adsorption of gold nanoparticle. The sensitivity of the proposed immunosensor has greatly improved as the PB‐SiO2 nanostructural sensing film provides plenty of active sites which might catalyze the reduction of H2O2. The immunosensor exhibited good linear behavior in the concentration range from 0.25–5.0 and 5.0–75 ng/mL for the quantitative analysis of neuron‐specific enolase (NSE), a putative serum marker of small‐cell lung carcinoma (SCLC), with a limit of detection of 0.08 ng/mL. The resulting NSE immunosensor showed high sensitivity and long‐term lifetime which can be attributed to the extremely high catalytic activity and biocompatibility of CS‐nanoAu/APTES/PB‐SiO2 nanostructural multilayers.  相似文献   
59.
A new mediator-free amperometric immunoassay for hepatitis B surface antigen (HBsAg) in human serum was designed by means of immobilizing horseradish peroxidase-hepatitis B surface antibodies conjugates (HRP-HBsAb) on ionic liquids-doped organic-inorganic hybrid film. The composite film including magnetic nanogold particles and nanoalumina particles provides a friendly microenvironment for the immobilization of biomolecules. The presence of ionic liquids enhances the electron communication between the immobilized biomolecules and the base electrode and improves the sensitivity of the electrochemical immunoassay. With a non-competitive immunoassay format, the formation of the immunocomplex between the immobilized HRP-HBsAb and HBsAg in sample solution exhibited a barrier of direct electrical communication between the immobilized HRP and the base electrode and changed the bioelectrocatalytic properties of the immobilized HRP towards H2O2 in the detection solution. Under optimal conditions, the developed immunosensors displayed a good current response in a dynamic range from 1.2 to 430 ng/mL with a limit of detection of 0.3 ng/mL HBsAg (at 3s). The proposed immunosensors have good precision, high sensitivity, acceptable stability, and reproducibility and could be used for the HBsAg detection in human serum with consistent results in comparison with those obtained by the enzyme-linked immunosorbent assay method.  相似文献   
60.
建立吴茱萸碱-β-环糊精的包合率测定方法。采用紫外分光光度法测定吴茱萸碱-β-环糊精的包合物中吴茱萸碱的含量,由此计算包合率。结果表明吴茱萸碱在225nm处有最大吸收,浓度在1.03—4.12μg.mL-1时与吸光度呈良好的线性关系,回归方程为:A=0.1661C+0.0145,r=0.9997(n=7);平均回收率为99.06%,RSD为0.61%。本法操作简便易行,具有良好的重现性和精密度。  相似文献   
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