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991.
992.
巴东栎中的黄酮类成分   总被引:5,自引:3,他引:5  
继上报之后 ,又从巴东栎 (QuercusenglerianaSeem .)叶片乙醇提取物中分离和鉴定了 6个黄酮类化合物 .它们是山萘酚 3 O β D 吡喃葡萄糖苷 (E9) ,山萘酚 3 O α L 吡喃阿拉伯糖苷(E10 ) ,槲皮素 3 O α L 吡喃阿拉伯糖苷 (E12 )和金丝桃苷 (E13) ,及 2个酰化黄酮山萘酚 3 O (2″ ,6″ 二 反式 对 肉桂酰基 3″ ,4″ 二 乙酰基 ) β D 吡喃葡萄糖苷 (E14)和山萘酚 3 O (2″ ,6″ 二 反式 对 肉桂酰基 ) β D 吡喃葡萄糖苷 (E15 ) .这些化合物均是首次从该种植物中分出  相似文献   
993.
The aim of this study was to develop a placebo model for bipolar disorder to help optimize clinical trial designs for studies targeting manic episodes in bipolar disorder. A bipolar disease database was built based on individual longitudinal data collected from over 3,000 patients in 11 clinical trials for 5 approved bipolar drugs. An empirical placebo effect model with an exponential decay process plus a linear progression process was developed to quantify the time course of the Young Mania Rating Scale total score based on only placebo data from the database. In order to describe the dropout pattern during the trials, a parametric survival model was developed and the Weibull distribution was identified to be the best distribution to describe the data. Based on the likelihood ratio test, it was found that patients with higher baseline score, slower disease improvement and more rapid disease progression tended to dropout earlier, and the trial features such as trial starting year and trial site were also significant covariates for dropout. A combination of the placebo effect model and the dropout model was applied to simulate new clinical trials through Monte-Carlo simulation. Both the placebo effect model and dropout model described the observed data reasonably well based on various diagnostic plots. The joint placebo response and dropout models can serve as a tool to simulate the most likely level of placebo response with the expected dropout pattern to help design a new clinical trial.  相似文献   
994.
目的观察单唾液酸四己糖神经节苷脂钠对Binswanger病患者认知力及日常生活能力的影响。方法将56例Binswanger病患者随机分为治疗组和对照组各28例,两组患者均予常规治疗,治疗组患者在此基础上给予单唾液酸四己糖神经节苷脂钠静滴,对照组患者给予胞二磷胆碱静滴,14天后采用MMSE量表和ADL量表评价两组患者的认知力及日常生活能力变化情况。结果治疗组患者MMSE量表改善总有效率为75%、ADL量表改善总有效率为67.86%,对照组患者MMSE量表改善总有效率为35.71%、ADL量表改善总有效率为32.14%。结论单唾液酸四己糖神经节苷脂钠治疗Binswanger病能够较好改善患者认知力及日常生活能力。  相似文献   
995.
Danshensu, as the effective component of Salvia miltiorrhiza (Danshen), has been widely used in clinical studies for treatment of cardiovascular diseases in China. A new metabolite, 4‐hydroxy‐3‐methoxyphenyllactic acid was isolated from the urine of rats, and its chemical structure was identified by ultraviolet (UV), Infrared Spectroscopy (IR), mass spectrometry (MS) and nuclear magnetic resonance (NMR). Furthermore, a selective and sensitive high performance liquid chromatography‐tandem mass spectrometric (HPLC‐MS/MS) method was developed for the simultaneous quantification of danshensu and its major metabolite, 4‐hydroxy‐3‐methoxyphenyllactic acid, in rat plasma after oral and intravenous administration of danshensu. The separation was performed on a Hypersil Gold C18 column (150 × 2.1 mm i.d., 3.0 µm, Thermo, San jose CA, USA) with gradient elution using a mobile phase composed of methanol and water (containing 0.1% formic acid) at a flow rate of 0.2 mL/min. Linear detection responses were obtained for danshensu and 4‐hydroxy‐3‐methoxyphenyllactic acid ranging from 5 to 10000 ng/mL and 5 to 4000 ng/mL, respectively. The lower limits of quantification (LLOQs) for the two compounds were both 5 ng/mL. The intra‐and inter‐day precision (R.S.D %) were within 5.61% for the two analytes. The average recoveries of the analytes were greater than 72.43%. The method was proved to be stable during all sample storage, preparation and analytic procedures. This method was successfully applied to the pharmacokinetic studies of danshensu and 4‐hydroxy‐3‐methoxyphenyllactic acid after oral and intravenous administration of danshensu in rats.Copyright © 2014 John Wiley & Sons, Ltd.  相似文献   
996.
生物合成调控的青霉素发酵数学模型与过程优化   总被引:4,自引:0,他引:4  
青霉素生物合成受溶解氧、溶解二氧化碳、pH、氨氮、碳源(特别是葡萄糖)等的调控,这些调控反应的产生不仅与基础培养基配方有关,更受发酵过程通气、搅拌条件及补料方案的影响。为此,笔者通过把握发酵过程中产生菌生长和青霉素生物合成代谢流的元素平衡、能量平衡以及传递与反应速度平衡的方法,结合生产经验和数据资料,建立了一种能够模拟青霉素发酵过程工艺学参数和经济学参数变化的数学模型。应用这一模型,在充分考虑生物合成代谢调控的基础上,对青霉素发酵过程进行优化,即通过补水维持上述平衡,避免因环境条件、初始条件和约束条件的变化及人为的失误造成的过程波动,使生产不断趋向最优状态。模拟运行表明,这种优化可显著提高发酵生产的经济效益。  相似文献   
997.
抗炎蛋白肽的分离和性质   总被引:2,自引:0,他引:2  
猪四肢骨提取物对大白鼠蛋清性关节炎及甲醛性关节炎具有显著抗炎作用,对酒石酸锑钾所引起的疼痛有镇痛作用,现已广泛用于治疗风湿、类风湿关节炎和骨质增生。我们通过葡聚糖凝胶G-25、G-50及羧甲基葡聚糖凝胶C-25等纯化步骤,获得一个蛋白肽组分。此组分经薄层层析鉴定为单一斑点,醋纤电泳为单一区带,凝胶柱等电聚焦为一条强带,一条弱带,分子量为27,000左右,不含糖类及核酸类物质,对大白鼠蛋清性关节炎具有明显的抗炎作用。初步认为此蛋白肽组分可能是猪四肢骨提取物中抗炎作用的有效物质。  相似文献   
998.
L-lysine monohydrochloride (LMH) dihydrate was crystallized and the resulting powder was sieved to obtain various size fractions. The influence of other factors, such as crystallinity and crystal shape, was minimized by using the same batch of crystals. Compression of smaller particles at low compaction pressures resulted in tablets of greater porosity. The differences in porosity decreased with increasing compaction pressure. At the same compaction pressure, smaller particles formed tablets of greater tensile strength. However, fragmentation of the larger particles tended to equalize the particle size and reduce its influence. The differences were reduced for particles larger than 710 microm. For crystals of all size fractions, tensile strength increased with increasing compaction pressure. The tensile strength increased more rapidly for smaller crystals. Tensile strength decreased exponentially with increasing porosity for all fractions. The dependence of tensile strength on porosity is explained in term of tablet structure. Yield strength, calculated from 'out-of-die' Heckel analysis, increased with increasing particle size.  相似文献   
999.
目的:制定新工艺护肝片的质量标准,验证新工艺的可行性。方法:对五味子、柴胡、猪胆粉进行薄层鉴别,用高效液相色谱法测定五味子醇甲的含量。结果:在选定的薄层色谱条件下,五味子、柴胡、猪胆粉的特征斑点清晰,五味子醇甲的线性范围为20.5~184.5μg·ml^-1,r=0.9999,平均回收率为99.2%,RSD0.57%,n=9。结论:护肝片的新工艺稳定,其质量标准专属性好。  相似文献   
1000.
The aporphine alkaloids (+)-dicentrine and (+)-bulbocapnine are non-planar molecules lacking features normally associated with DNA binding by intercalation or minor groove binding. Surprisingly, dicentrine showed significant activity as a topoisomerase II (EC 5.99.1.3) inhibitor and also was active in a DNA unwinding assay. The DNA unwinding suggests DNA intercalation, which could explain the inhibition of topoisomerase II. Bulbocapnine, which differs from dicentrine only by the presence of a hydroxyl group at position 11 and the absence of a methoxyl group at position 9, was inactive in all assays. Molecular modeling showed that dicentrine can attain a relatively planar conformation, whereas bulbocapnine cannot, due to steric interaction between the 11-hydroxyl group and an oxygen of the methylenedioxy ring. These observations suggest that dicentrine is an "adaptive" DNA intercalator, which can bind DNA only by adopting a somewhat strained planar conformation. The requirement of a suboptimal conformation to achieve DNA binding appears to make dicentrine a weaker topoisomerase II inhibitor than the very planar oxoaporphine alkaloid liriodenine. These results suggest that it may be possible to modulate DNA binding and biologic activity of drugs by modifications affecting their ability to adopt planar conformations.  相似文献   
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