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31.
建立了一种快速、灵敏、准确的同时测定牛蛙全血中双酚A、己烯雌酚、己二烯雌酚、己烷雌酚、4-叔辛基酚和4-壬基酚等6种酚类环境雌激素的分散固相萃取-超快速液相色谱-串联质谱(dSPE-UFLC-MS/MS)分析方法。牛蛙全血样品经含0.1%(v/v)甲酸的甲醇溶液沉淀蛋白后,利用自制的氨基功能化Fe3O4磁性高分子复合微粒(EDA-MPs)作为dSPE吸附剂进行净化,着重考察了沉淀剂、吸附净化时间、吸附剂用量等因素对6种酚类环境雌激素回收率的影响。采用Shim-pack XR-ODSII(100 mm×2.0 mm, 2.2 μm)反相液相色谱柱进行分离,在电喷雾离子源(ESI)负离子多反应监测(MRM)模式下进行检测。结果表明: 6种酚类环境雌激素在0.5~100.0 μg/L范围内具有良好的线性关系(r2≥0.9996),方法的定量限(信噪比大于10)为0.075~0.40 μg/L,方法的精密度为0.6%~6.3%,空白样品中3个不同水平的添加回收率为95.0%~110.0%。本方法适用于牛蛙全血中6种酚类环境雌激素的同时测定。 相似文献
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目的观察病态窦房结综合征患者心房颤动负荷与红细胞分布宽度(RDW)的关系。方法选择病态窦房结综合征植入永久性人工心脏起搏器的患者81例,回顾性分析患者入院时基本资料、血常规及生化指标。记录术后3个月起搏器记录的心房颤动负荷。根据患者心房颤动负荷分为高负荷组及低负荷组,比较分析两组患者RDW及相关临床资料。结果心房颤动高负荷组患者RDW(15.61±1.23)%,高血压比例71%,明显高于低负荷组的(13.50±1.03)%、46%(P<0.01或0.05)。高负荷组左心房直径、左心室舒张末期内径、WBC、TG、TC均大于低负荷组(P<0.01或0.05)。心房颤动负荷影响因素的logistic回归分析显示,RDW是心房颤动负荷高的预测因素(OR=10.32,P<0.01)。高TG、高血压、高胆固醇也是心房颤动高发的预测因素。结论心房颤动负荷除与年龄,高血压有关外,还与RDW明显相关。RDW可成为病态窦房结综合征患者心房颤动负荷的预测因素之一。 相似文献
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变延迟进动定制激发(Delays Alternating with Nutation for Tailored Excitation,DANTE)序列作为一种黑血预脉冲序列,通过连续施加小角度激发脉冲,以及结合散相梯度,使得流动物质和静态物质达到不同的稳态,从而抑制流动的血液.对于静态物质而言,施加DANTE序列后在图像等间隔的位置会出现暗条纹,暗条纹的宽度与梯度幅值和小单元持续时间乘积相关:乘积越大,暗纹宽度越小.对于动态物质而言,为达到较好的抑制效果,需要增加整个DANTE序列模块的准备时间,并且增大梯度幅值和小单元持续时间的乘积.因此,该方法对于梯度系统的要求较高,而实际梯度放大器(Gradient Amplifier,GPA)有一定的限额.在有限的GPA条件下,为使得DANTE序列具有更好抑制流动信号效果,本文在读出方向以及片层旋转两个方面进行了梯度优化,实现了更好的黑血效果. 相似文献
36.
光声成像结合了光学成像和声学成像的优点,是一种高分辨率,高对比度的无损伤医学成像技术.一种改进的同步迭代算法应用于光声图像重建.仿真和模拟结果表明,与传统的代数迭代算法相比,在90°,135°,180°的有限场光声成像中,此算法对测量误差的校正和迭代次数的收敛上具有较大的优势,图像重建的速度和成像质量都有了明显的提高.实验中,一种圆形扫描结构的光声成像装置,用于180°的有限场扫描,利用改进的同步迭代算法,重建出了高对比度和高分辨率(60μm)的鸡胚胎光声血管图像.实验证明,这种算法的应用,大幅度减少了数据采集时间,为光声成像技术运用于实时监测血流灌注和肿瘤光动力治疗的血管损伤效应提供了潜在的应用价值.
关键词:
光声成像
有限角度
代数迭代算法
光声血管成像 相似文献
37.
《Macromolecular bioscience》2018,18(5)
A method is developed that can rapidly produce blood vessel‐like structures by bonding cell‐laden electrospinning (ES) films layer by layer using fibrin glue within 90 min. This strategy allows control of cell type, cell orientation, and material composition in separate layers. Furthermore, ES films with thicker fibers (polylactic‐co‐glycolic acid, fiber diameter: ≈3.7 µm) are used as cell‐seeding layers to facilitate the cell in‐growth; those with thinner fibers (polylactic acid, fiber diameter: ≈1.8 µm) are used as outer reinforcing layers to improve the mechanical strength and reduce the liquid leakage of the scaffold. Cells grow, proliferate, and migrate well in the multilayered structure. This design aims at a new type of blood vessel substitute with flexible control of parameters and implementation of functions. 相似文献
38.
Lin Cheng Xiaoyun Wei Zixiang Wang Chun Feng Qing Gong Yourong Fu Xingzhong Zhao Yuanzhen Zhang 《Electrophoresis》2020,41(10-11):966-972
ABO hemolytic disease of the newborn (ABO-HDN), which may cause neonatal jaundice and polycythemia, or even stillbirth or neonatal death, is widespread in China. Prenatal testing for the fetal ABO blood group can reduce unnecessary concerns or ensure prompt treatment. Herein, we presented a method to employ high-density silica microbeads (SiO2 MBs) for capturing fetal nucleated red blood cells (fnRBCs) in maternal peripheral blood, and we detected the ABO genotype of the fetus using these captured cells. We evaluated 52 patients using the SiO2 MBs. Among 26 pregnant women with type O blood, 8 (30.8%) of the fetuses had type A blood, 5 (19.2%) had type B blood, and 13 (50%) had type O blood. SRY genes were detected in all 27 male fetuses. This study represents a simple and effective method for noninvasive prenatal detection of the fetal ABO genotype. We believe that this method has great potential for noninvasive prenatal testing of the fetal Rh blood group and other fetal diseases as well. 相似文献
39.
Dr. Jagadeesh Yerri Dr. José Dias Dr. Mallikajurna Reddy Nimmakayala Franck Razafindrainibe Charlotte Courageux Anne-Julie Gastellier Johanne Jegoux Dr. Caroline Coisne Dr. Christophe Landry Dr. Fabien Gosselet Johan Hachani Dr. Jean-François Goossens Prof. Marie-Pierre Dehouck Dr. Florian Nachon Dr. Rachid Baati 《Chemistry (Weinheim an der Bergstrasse, Germany)》2020,26(65):15035-15044
Novel 6-alkyl- and 6-alkenyl-3-fluoro-2-pyridinaldoximes have been synthesised by using a mild and efficient chemoselective hydrogenation of 6-alkynyl-3-fluoro-2-pyridinaldoxime scaffolds, without altering the reducible, unprotected, sensitive oxime functionality and the C−F bond. These novel 6-alkyl-3-fluoro-2-pyridinaldoximes may find medicinal application as antidotes to organophosphate poisoning. Indeed, one low-molecular-weight compound exhibited increased affinity for sarin-inhibited acetylcholinesterase (hAChE) and greater reactivation efficiency or resurrection for sarin-inhibited hAChE, compared with those of 2-pyridinaldoxime (2-PAM) and 1-({[4-(aminocarbonyl)pyridinio]methoxy}methyl)-2-[(hydroxyimino)methyl]pyridinium chloride (HI-6), two pyridinium salts currently used as antidote by several countries. In addition, the uncharged 3-fluorinated bifunctional hybrid showed increased in vitro blood–brain barrier permeability compared with those of 2-PAM, HI-6 and obidoxime. These promising features of novel low-molecular-weight alkylfluoropyridinaldoxime open up a new era for the design, synthesis and discovery of central non-quaternary broad spectrum reactivators for organophosphate-inhibited cholinesterases. 相似文献
40.
Harsha K. Tripathy Nair S.V. Manju Sreekanth Dittakavi Ram Murthi Bestha Ramesh Mullangi 《Biomedical chromatography : BMC》2020,34(12):e4953
Larotrectinib is a first-generation tropomyosin kinase inhibitor, approved for the treatment of solid tumors. In this paper, we present a validated dried blood spot (DBS) method for the quantitation of larotrectinib from mouse blood using HPLC–MS/MS, which was operated under multiple reaction monitoring mode. To the DBS disc cards, acidified methanol enriched with internal standard (IS; enasidenib) was added and extracted using tert-butyl methyl ether as an extraction solvent with sonication. Chromatographic separation of larotrectinib and the IS was achieved on an Atlantis dC18 column using 10 mm ammonium formate–acetonitrile (30:70, v/v) delivered at a flow-rate of 0.80 ml/min. Under these optimized conditions, the retention times of larotrectinib and the IS were ~0.93 and 1.37 min, respectively. The total run time was 2.50 min. Larotrectinib and the IS were analyzed using positive ion scan mode and parent–daughter mass to charge ion (m/z) transitions of 429.1 → 342.1 and 474.1 → 267.1, respectively, were used for the quantitation. The calibration range was 1.06–5,080 ng/ml. No matrix effect or carryover was observed. Hematocrit did not influence DBS larotrectinib concentrations. All of the validation parameters met the acceptance criteria. The applicability of the validated method was shown in a mouse pharmacokinetic study. 相似文献