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71.
冬青素A系中药毛冬青的主要成分之一, 本文建立了液相色谱质谱法(LC-MS)研究冬青素A在大鼠体内的药动学特征。色谱分离采用C18柱, 甲醇-5 mM 醋酸铵(80:20, v/v) 为流动相质谱检测采用ESI源, 负离子检测, 冬青素A的检测离子为m/z 501.1→501.1,地高辛(内标) 的检测离子为m/z779.4→779.4。大鼠血浆加入磷酸溶液以乙酸乙酯提取, 分取有机层以氮气流吹干, 流动相复溶后进行LC-MS分析。方法学评价表明该法定量限为1.05 ng/mL, 在1.05-525.5 ng/mL范围内线性关系良好。日内和日间变异均小于10%, 提取回收率大于80%。采用建立的LC-MS法进行了大鼠单剂量口服冬青素A后, 其在大鼠体内的药动学研究, 获得了主要的药动学参数。 相似文献
72.
Karolina Orywal Katarzyna Socha Patryk Nowakowski Wojciech Zo Barbara Mroczko Maciej Perkowski 《Nutrients》2022,14(13)
Dried mushrooms might be a source of mineral components, which are indispensable for human health. The aim of this study was to determine the contents of calcium (Ca), magnesium (Mg), iron (Fe), zinc (Zn), copper (Cu), manganese (Mn), and selenium (Se) in dried wild-grown mushrooms (Boletus edulis and Xerocomus badius) available for sale, and to evaluate these mushrooms’ contribution to the daily reference intake of the studied bioelements. The concentrations of mineral components in the mushroom samples were determined by the flame method (Ca, Mg, Fe, Zn, Cu, Mn) and the electrothermal (Se) atomic absorption spectrometry method. The mean Ca, Mg, Fe, Zn, Cu, Mn (in mg/kg), and Se concentrations (in µg/kg) in B. edulis were 82.1, 964.1, 233.4, 97.9, 25.3, 22.1, and 6501.6, respectively, whereas in X. badius: 67.5, 1060.2, 87.8, 197.2, 33.9, 19.8, and 282.4, respectively. We have shown that dried B. edulis can be considered a source of Se. In the case of the other microelements, the tested mushrooms may serve only as additional supplements. Therefore, the studied species of mushrooms cannot be regarded as potential nutritional sources of the macroelements in question. Consumers should be properly informed about this, which should be guaranteed by appropriate legal regulations. 相似文献
73.
健康人肝组织麦胚凝集素亲和型糖蛋白表达谱分析 总被引:1,自引:0,他引:1
目的分析健康人肝组织麦胚凝集素(wheatgermagglutinin,WGA)亲和型糖蛋白表达谱。方法从30例健康人肝组织混合样本的总蛋白中用WGA凝集素亲和层析分离纯化糖蛋白,再利用双向电泳结合SYPRO Ruby荧光染色进一步分离WGA亲和型糖蛋白。目的蛋白质点经质谱鉴定后对其进行生物信息学分析及功能分类。结果初步建立WGA亲和型糖蛋白的双向电泳图谱,图谱均点数为(650±50)个,质谱鉴定并去冗余共获116个蛋白。经生物信息学分析104个蛋白具有不同程度的N糖基化位点,最后按Gene Ontology的分类原则进行功能分类。结论凝集素亲和层析结合双向电泳荧光染色、质谱鉴定是一种高通量的检测方法,WGA亲和型糖蛋白表达谱的初步构建为后续研究奠定了基础。 相似文献
74.
Sarang Younesi Bahareh Yazdani Mohammad Mahdi Taheri Amin Pourandokht Saadati Soudabeh Jamali MohammadHossein Modarresi Shahram Savad Saloomeh Amidi Homayoun Razavi Soudeh GhafouriFard 《Journal of clinical laboratory analysis》2022,36(7)
BackgroundNowadays, neonatal screening has become an essential part of routine newborn care in the world. This is a non‐invasive evaluation that evaluated inborn errors of metabolisms (IEMs) using tandem mass spectrometry (LC‐MS/MS) for the evaluation of the baby''s risk of certain metabolic disorders.MethodsThis retrospective study was conducted on 39987 Iranian newborns who were referred to Nilou Medical Laboratory, Tehran, Iran, for newborn screening programs of IEMs. We incorporated second‐tier tests and secondary biomarkers to improve positive predictive value (PPV).ResultsStatistical data were recorded via call interviewing in 6–8 months after their screening tests. The overall prevalence of IEM was 1:975. The mean age of all participants was 3.9 ± 1.1 days; 5.1% of participants were over 13 days and 7.7% were preterm or underweight. A total of 11384 (29.4%) of the cases were born in a consanguineous family. The type of delivery was the cesarean section in 8332 (51.3%) valid cases. The neonatal screening results had an overall negative predictive value (NPV) of 100% and the overall PPV of 40.2%. The false‐positive rate was 0.15%.ConclusionThis study showed a high incidence of metabolic disease due to a high rate of consanguineous marriages in Iran and indicated that incorporation of second‐tier tests and secondary biomarkers improves PPV of neonatal screening programs. 相似文献
75.
阿片类拮抗药纳美芬注射剂的单剂量和多剂量Ⅰ期临床药代动力学研究 总被引:1,自引:0,他引:1
目的 考察静脉推注盐酸纳美芬注射液后在健康人体内的药动学过程.方法 12名健康受试者随机交叉单剂量静脉推注给药2 mg后,分别于给药前和给药后5 min,0.25,0.5,1,1.5,2,2.5,3,4,6,8,12,24,36和48 h采集血样,单剂量试验结束后进人多剂量试验.8名受试者静脉推注给药2mg,连续给药6d,并于给药后的第4,5,6天早上给药前采静脉血,于第6天给药后按设定时间点采集血样,用高效液相色谱-质谱法测定血浆中纳美芬的浓度,并采用PKS药动学程序对试验数据进行处理,求算有关药动学参数.结果 单剂量静脉推注盐酸纳美芬注射液2 mg后,其药-时曲线经拟合符合二室模型,12名健康受试者单剂量给药后其主要药动学参数Cmax,Tmax,T1/2,AUC0-48,AUC0-∞分别为(7.34±1.56)μg·L-1,0.08 h,(12.01±2.20)h,(30.29±9.84)μg·L-1·h,(32.23±9.94)μg·L-1·h,多次静脉推注2 mg后的主要药动学参数Cmax,Tmax,T1/2,AUC0-48,AUC0-∞分别(8.04±1.09)μg·L-1、0.08 h、(12.43±1.44)h、(33.64±9.15)μg·L-1·h和(35.98±9.23)μg·L-1·h,血药浓度波动系数、AUCss和Cav分别为(4.69±1.29)、(19.64±6.20)μg·L-1·h和(1.64±0.52)μg·L-1.结论 盐酸纳美芬注射液单剂量静脉推注2 mg和多次给药2 mg后人体内的药动学行为与国外文献报道基本一致.在连续多次给药时,并未出现蓄积现象,血药浓度第6天达稳态. 相似文献
76.
目的:串联质谱技术是近几年应用于临床检验的新技术,具有特异性强、灵敏度高,一次试验可检测数十种物质的优点。本文通过对近4年的质控结果进行分析,探讨影响检测结果的因素及应对措施。方法:美国CDC每年提供4批酰基肉碱质控干血滤纸片,酰基肉碱检测方法为取直径为3mm的质控干血滤纸片放入96孔聚丙烯板,经含酰基肉碱内标的甲醇萃取,盐酸正丁醇衍生后,进行串联质谱检测。分析本实验室质控结果与美国CDC检测结果的偏差及其他实验室质控结果(169个实验室的均值)与美国CDC检测结果的偏差之间的差异。结果:本实验室每次质控结果所有酰基肉碱均在美国CDC检测结果95%可信区间内,且每一批结果的临床评价与美国CDC质控临床评价完全一致。本实验室质控结果与美国CDC检测结果的偏差与其他实验室质控结果与美国CDC检测结果的偏差比较,无显著差异,丙酰基肉碱差异显著(Z=-2.638,P〈0.005),戊二酰基肉碱差异亦显著(Z=-2.482,P〈0.005)。结论:本实验室酰基肉碱质控结果,达到美国CDC的质控要求,丙酰基肉碱检测值偏高,其阳性判断切割值设定也相应增高,而戊二酰基肉碱检测值偏低,其阳性判断切割值设定也相应降低。 相似文献
77.
Fengyu Zhang Bichen Li Ying Wen Yanyang Liu Rong Liu Jing Liu Shao Liu Yueping Jiang 《Pharmaceutical biology》2022,60(1):1349
ContextThe extracts of Aspongopus chinensis Dallas (Pentatomidae), an insect used in traditional Chinese medicine, have a complex chemical composition and possess multiple pharmacological activities.ObjectiveThis study comprehensively characterizes the chemical constituents of A. chinensis by an integrated targeted and untargeted strategy using UPLC-QTOF-MS combined with molecular networking.Materials and methodsThe ultra-performance liquid chromatography-tandem quadrupole time-of-flight mass spectrometry (UPLC-QTOF-MS) combined with molecular networking-based dereplication was proposed to facilitate the identification of the chemical constituents of aqueous and ethanol extracts of A. chinensis. The overall strategy was designed to avoid the inefficiency and costliness of traditional techniques. The targeted compounds discovered in the A. chinensis extracts were identified by searching a self-built database, including fragment ions, precursor ion mass, and other structural information. The untargeted compounds were identified by analyzing the relationship between different categories, fragmentation pathways, mass spectrometry data, and the structure of the same cluster of nodes within the molecular network. The untargeted strategy was verified using commercial standard samples under the same mass spectrometry conditions.ResultsThe proposed integrated targeted and untargeted strategy was successfully applied to the comprehensive profiling of the chemical constituents of aqueous and ethanol extracts of A. chinensis. A total of 124 compounds such as fatty acids, nucleosides, amino acids, and peptides, including 74 compounds that were reported for the first time, were identified in this study.ConclusionsThe integrated strategy using LC tandem HRMS combined with molecular networking could be popularised for the comprehensive profiling of chemical constituents of other traditional insect medicines. 相似文献
78.
目的:采用分子吸收光度法测定万寿菊中代森锰锌残留。方法:通过蒸馏和溶液吸收实验装置,氯化亚锡催化,二乙基二硫代氨基甲酸钠分解定量产生二硫化碳气体,通过浓硫酸脱氧脱水,氢氧化钾的甲醇液吸收,用分光光度法在304 nm波长处测定其标准曲线。代森锰锌以平均相对分子质量333计,可通过平均相对分子质量计算出代谢锰锌的含量。结果:万寿菊中添加浓度为10 mg.kg-1和20 mg.kg-1(以二硫化碳计)的回收率(n=5)分别为95.9%和93.2%,RSD分别为4.8%和3.7%;最低检测限为2 mg.kg-1。结论:该方法操作简单,灵敏度高,适合大批量样品的检测。 相似文献
79.
80.