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排序方式: 共有455条查询结果,搜索用时 15 毫秒
451.
Zeyu Zhang Yawei Qu Yu Cao Xiaojing Shi Hongbo Guo Xiaojun Zhang Sheng Zheng Haifeng Liu Zhenhua Hu Jie Tian 《Journal of biophotonics》2020,13(3)
Intraoperative Cerenkov luminescence imaging (CLI) can effectively improve the performance of tumor surgery. Nevertheless, the existing approaches are still unsatisfying to the clinical demands of open surgery. This study develops a novel intraoperative in vivo CLI approach to investigate the potential and value of Cerenkov luminescence (CL) image‐guided surgery. A system characterized with high sensitivity (19.61 kBq mL?1 18F‐FDG) and desirable spatial resolution (88.34 μm) is developed. CL image‐guided surgery is performed on colorectal cancer (CRC) models of mice and swine. Tumor surgery is guided by the static CL images, and the resection quality is evaluated quantitatively and contrasted with other imaging modalities exemplified by bioluminescence imaging (BLI). The in vivo results demonstrated the effectiveness of the proposed intraoperative CLI approach for removing primary and metastatic CRC. Safety of performing in vivo CL image‐guided surgery is verified as well through radiation measurements of related staffs. Overall, the developed intraoperative in vivo CLI approach can efficiently improve the cancer treatment. 相似文献
452.
传统链霉亲和素磁珠体系及酶促发光体系中通常存在生物素干扰强、发光率低、特异性差的缺陷。基于此,以裸磁珠为载体偶联血清淀粉样蛋白A(serum amyloid A, SAA)抗体,以吖啶酯作为发光标记物,依据双抗夹心原理,建立了一种快速测定SAA的方法,并对该方法的检测性能(包括:空白限、检测限、线性范围、精密度验证、干扰试验、HOOK效应、方法学比较等)进行了评估。结果表明,SAA抗体与裸磁珠成功偶联;该方法空白限为0.6 mg·mL-1,检出限为1.0 mg·mL-1;线性范围为1~100 mg·mL-1 (R2>0.990);在精密度方面,以CV表示的重复性、室内精密度均<10%;血红蛋白、胆红素、甘油三酯对临床样本的干扰检测结果相对偏差均<10%。Bland-Altman偏倚分析表明,该方法检测值与西门子试剂的测量值差异基本在95%CI的一致性界限内波动,回归分析结果显示有较好的相关性(R2=0.987)。上述结果表明,研究所建立的裸磁珠-吖啶酯发光检测体系性能参数可满足临床检测要求,适用于血清中SAA的快速检测。 相似文献
453.
Physiological Links in Firefly Flash Code Evolution 总被引:4,自引:0,他引:4
New and reassessed neurophysiological observations on dialog fireflies permit (1) parsimonious inferences about the origin and fixation of light emission in the primeval firefly, (2) proof of widespread involvement of a stable species-specific minimal stimulus–response interval in timed flashing behaviors of both genders, (3) strengthening of the evidence for certain normally latent flash control intervals common to both male and female, (4) assignment of possible roles in the evolution of time-coded courting dialog to these data, and (5) evaluation of the evolutionary status of certain present-day species. 相似文献
454.
X‐ray‐induced luminescence computed tomography (XLCT) is an emerging molecular imaging. Challenges in improving spatial resolution and reducing the scan time in a whole‐body field of view (FOV) still remain for practical in vivo applications. In this study, we present a novel XLCT technique capable of obtaining three‐dimensional (3D) images from a single snapshot. Specifically, a customed two‐planar‐mirror component is integrated into a cone beam XLCT imaging system to obtain multiple optical views of an object simultaneously. Furthermore, a compressive sensing based algorithm is adopted to improve the efficiency of 3D XLCT image reconstruction. Numerical simulations and experiments were conducted to validate the single snapshot X‐ray‐induced luminescence computed tomography (SS‐XLCT). The results show that the 3D distribution of the nanophosphor targets can be visualized much faster than conventional cone beam XLCT imaging method that was used in our comparisons while maintaining comparable spatial resolution as in conventional XLCT imaging. SS‐XLCT has the potential to harness the power of XLCT for rapid whole‐body in vivo molecular imaging of small animals. 相似文献
455.
Lars-Göran Sundblad Göran Samuelsson Bosse Wigge Per Gardeström 《Photosynthesis research》1990,23(3):269-282
Two green algal species, Chlamydomonas reinhardtii and Scenedesmus obliquus, exhibited a relative maximum during the decay of luminescence, when adapted to low CO2 conditions that was not observed in high CO2 adapted cells.From the kinetics of transient changes in the level of dark fluorescence, after illumination and parallel to the luminescence maxima, it was concluded that the maximum in Scenedesmus was mainly related to a decrease in nonphotochemical quenching, whereas in Chlamydomonas the maximum was mainly related to a dark reduction of the primary PS II acceptor QA.ATP/ADP ratios from low CO2 adapted Scenedesmus showed transient high levels after a dark/light transition that was not observed in high CO2 adapted cells. After 30 s of illumination the ATP/ADP ratios however stabilized at the same steady state level as in high CO2 adapted cells.Dark addition of HCO3
- to low CO2 adapted cells of Chlamydomonas resulted in a rapid transient quenching of luminescence that was not observed in low CO2 adapted cells of neither species.It is concluded that the luminescence maxima present in both low CO2 adapted Scenedesmus and Chlamydomonas reflect adaptation of the cells to low CO2 conditions. It is further suggested that the difference in mechanistic origin of luminescence maxima in the two species reflects differences in adaptation.Abbreviations ADP
adenosine-diphosphate
- ATP
adenosine-triphosphate
- Ci
inorganic carbon
- FD
dark fluorescence recorded under dark adapted conditions
- F0
fluorescence with all reaction centers open
- FV
variable fluorescence
- PS I
photosystem I
- PS II
photosystem II
- QA
the first quinone acceptor of PS II 相似文献