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851.
Kim HY Hwang JY Han BG Lee JY Park EK Kim BJ Lee SH Kim GS Kim SY Koh JM 《Experimental & molecular medicine》2012,44(6):394-402
Adiponectin may affect bone through interactions with two known receptors, adiponectin receptors (ADIPOR) 1 and 2. We examined the association between polymorphisms of ADIPOR1 and ADIPOR2 and bone mineral density (BMD) in postmenopausal Korean women. Six polymorphisms in ADIPOR1 and four polymorphisms in ADIPOR2 were selected and genotyped in all study participants (n = 1,329). BMD at the lumbar spine and femur neck were measured using dual-energy X-ray absorptiometry. Lateral thoracolumbar (T4-L4) radiographs were obtained for vertebral fracture assessment and the occurrence of non-vertebral fractures examined using self-reported data. P values were adjusted for multiple testing using Bonferroni correction (P(corr)). ADIPOR1 rs16850799 and rs34010966 polymorphisms were significantly associated with femur neck BMD (P(corr) = 0.036 in the dominant model; P(corr) = 0.024 and P(corr) = 0.006 in the additive and dominant models, respectively). Subjects with the rare allele of each polymorphism had lower BMD, and association of rs34010966 with BMD showed a gene dosage effect. However, ADIPOR2 single nucleotide polymorphisms and haplotypes were not associated with BMD at any site. Our results suggest that ADIPOR1 polymorphisms present a useful genetic marker for BMD in postmenopausal Korean women. 相似文献
852.
用阿魏酸与Fe、Co、Ni、Cu、Zn的硝酸盐制备了5种过渡金属配合物,通过红外光谱、热重-差热分析、元素分析、荧光和紫外光谱的方法对配合物进行了表征,确定了配合物的组成。并对配体和配合物进行了全血凝血时间、复钙时间、活化部分凝血活酶时间、凝血酶原时间的测定,结果表明5种配合物具有较好的抗凝血性质。通过荧光光谱、紫外光谱、圆二色谱研究了配合物与人血清白蛋白(HSA)的相互作用,HSA的荧光光谱表明配合物对其有荧光猝灭作用并使其发射峰位置红移,紫外光谱表明配合物的加入导致HSA吸收强度增加且吸收峰位置紫移,圆二色谱表明配合物的存在可引起HSA构象的变化。推测配合物抗凝血作用的起效与其和血清白蛋白之间的相互作用有一定的联系。 相似文献
853.
854.
《Analytical letters》2012,45(12):2417-2428
Abstract A simple, sensitive, and specific flow injection fluorimetric method has been developed for the determination of carbamazepine (CBZ). The proposed method is based on use of a solid‐phase reactor containing lead dioxide for on‐line oxidization of CBZ into a strongly fluorescent compound in a medium of phosphoric acid. The product has a green‐yellow fluorescence at a maximum excitation wavelength of 355 nm and an emission wavelength of 478 nm. Under the optimum conditions, the fluorescence intensity is proportional to the concentration of CBZ ranging from 0.0005 to 4.000 µg mL?1. The detection limit is 5.7×10?5 µg mL?1 (2.4×10?10 mol L?1) and the relative standard deviation is 1.4% at the sampling rate of 45 h?1. The proposed method has been applied to clinical estimation of CBZ in real patients' plasma samples with the results compared with those obtained by HPLC method. 相似文献
855.
《Analytical letters》2012,45(4):561-570
Abstract A simple reverse‐phase high‐performance liquid chromatographic method for the determination of tenofovir disoproxil fumarate (TDF) in pharmaceutical formulations and human plasma samples has been developed and validated. Piroxicam (PRX) was used as an internal standard. The assay of the drug was performed on a CLC C18 (5 μ, 25 cm×4.6 mm i.d.) with UV detection at 259 nm. The mobile phase consisted of acetonitrile–water mixture in the ratio of 75∶25, and a flow rate of 1 ml/min was maintained. The standard curve was linear over the range of 0.2–10 µg/ml (r 2=0.9966). Analytic parameters have been evaluated. Within‐day and between‐day precision as expressed by relative standard deviation was found to be less than 2%. The method has been applied successfully for the determination of TDF in spiked human plasma samples and pharmaceutical formulations. 相似文献
856.
《Analytical letters》2012,45(5):806-821
Abstract The voltammetric behavior of rosiglitazone was studied using direct current (DCt), differential pulse (DPP), and alternating current (ACt) polarography. The drug manifests cathodic waves over a pH range of 2–11.2. In Britton‐Robinson buffer (BRb; pH 4), the diffusion current–concentration relationship was found to be rectilinear over a range of 4–24 µg · mL?1 and 0.1–16 µg · mL?1 using DCt and DPP modes, respectively, with minimum limits of detection (LOD) of 0.15 µg · mL?1 and 0.07 µg · mL?1 using the DCt and DDP modes, respectively. The diffusion‐current constant (I d) was 6.63±0.03 (n=5). The proposed method was successfully applied to the determination of the studied compound both in pure form and in formulations. The mean percentage recoveries in tablets were 100.09±1.18 and 100.85±0.88 (n=5) using DCt and DPP modes, respectively. Furthermore, the proposed method, adopting the DPP mode, was applied to the determination of rosiglitazone in spiked human plasma and the obtained mean percentage recoveries were 99.14±3.29 (n=4). 相似文献
857.
金纳米粒子富集-高效液相色谱同时测定人血浆中三种氨基硫醇 总被引:1,自引:0,他引:1
建立了金纳米粒子富集-高效液相色谱-紫外检测(HPLC-UVD)同时测定人血浆中3种氨基硫醇(半胱氨酸(Cys)、高半胱氨酸(Hcys)、谷胱甘肽(GSH))的新方法。以Tween 20修饰的金纳米粒子作为选择探针萃取富集氨基硫醇。经二硫苏糖醇脱附后,采用SpursilTM C18柱(250 mm×4.6 mm, 5 μm)分离氨基硫醇,以60 mmol/L磷酸盐缓冲溶液(pH 2.0)等度洗脱,检测波长为200 nm。3种氨基硫醇的浓度分别在0.025~350 μmol/L、0.02~60 μmol/L、0.01~50 μmol/L内与峰面积具有良好的线性关系,相关系数均高于0.99。方法检出限(信噪比为3)分别为5.0、6.0和2.5 nmol/L,回收率为92.8%~106.0%。该方法能显著降低血浆样品中内源性物质的干扰,提高HPLC-UVD的选择性和灵敏度。将该方法应用于心血管病人血浆中上述氨基硫醇的分离测定,结果显示: 与对照组相比,疾病组血浆中的Hcys和GSH水平存在显著性差异,Cys不存在显著性差异。 相似文献
858.
大孔及涂敷硅球作基质的组氨酸拟亲和色谱纯化人免疫球蛋白G 总被引:1,自引:1,他引:1
研究用分子组氨酸和配体、大孔硅球为基质的拟亲和色谱分离纯化人免疫蛋白G(IgG),认为键合组氨酸具有半抗原体质而与IgG发生免疫亲和作用,以色谱组份重新进样验证了色谱柱对IgG亲和专一性,并用包敷Dextran大孔硅球作基质的拟亲和色谱纯化人血清中的IgG,减少了色谱峰拖尾,缩短了分离时间。 相似文献
859.
血清中阿斯匹林和水杨酸浓度的快速高效液相色谱法测定 总被引:3,自引:0,他引:3
A fast method for determining concentrations of aspirin and salicylic acid in serum using reversedphase high performance liquid chromatography with Spherisorb C18 column,MeOH i H2O: n-BuOH : H3PO4 (300:200 :10 :0. 5,volume ratio) eluent and UV-237 detector was eatablished. The linear range of the method is 1-20μg/mL (r=0. 9996)for aspirin and 2 30μg/mL (r=0. 9981) for salicylic acid. The averagerecoveries are 96. 0 %-106. 0% and 92. 0%-119.5% ,respectively. 相似文献
860.
液相色谱法测定血浆中三环类抗忧郁药物 总被引:2,自引:0,他引:2
用高效液相色谱法测定了血浆中4种三环类抗忧郁药物:卡马西平、氯氮平、多虑平和阿米替林。方法采用C_(18)色谱柱分离,二极管阵列检测器检测,流动相为甲醇:0.5mol/L三乙胺-0.5mol/L冰醋酸的水溶液(90:10,V/V;pH7.5)。标准曲线的线性范围为0~10mg/L,相关系数在0.99以上。方法的最小检出浓度为10~40μg/L血浆。血中药物经溶剂萃取后,药物的回收率为73.67%~98.24%,血中杂质不影响药物的检测。方法简便、快速,适用于临床中毒样品的分析。 相似文献