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1.
The objective of the present study was the development and validation of the method for determining AMB-FUBINACA and its metabolite - AMB-FUBINACA O-desmethyl acid – in blood samples, followed by verification of the method in toxicological judicial and forensic medicine practice employing the example of post-aggression suicide. Most likely in consequence of development of adverse effects resulting in psychotic symptoms, a male being under the influence of the synthetic cannabinoid AMB-FUBINACA and the new synthetic opioid U-47700, mortally wounded his female partner and subsequently committed suicide. Identification and determination of the afore-mentioned xenobiotics in blood samples collected from the male and female victims were performed employing high performance liquid chromatography coupled with electrospray ionization tandem mass spectrometry (HPLC-ESI-MS/MS). The analytes were isolated from blood samples using the solid phase extraction (SPE) method. The blood samples collected from the male and female demonstrated respectively 110 and 196 ng/mL of AMB-FUBINACA O-desmethyl acid metabolite, 1935 and 357 ng/mL of U-47700, 250 and 200 ng/mL of N-desmethyl-U-47700, as well as 410 and 200 ng/mL of N,N-didesmethyl-U-47700. The concentration values of new psychoactive substances (NPS’s) in blood samples originating from the male and female were within the ranges encountered in cases of poisoning, including these resulting in death. Nevertheless, the evident signs of exsanguination proof that the woman was alive when she sustained lethal injuries. The presented cases illustrate the difficult to be anticipated effect exerted on the users by NPS’s.  相似文献   
2.
Zedoary tumeric (Curcumae Rhizoma, Ezhu in Chinese) has a long history of application and has great potential in the treatment of liver cancer. The anti liver cancer effect of zedoary tumeric depends on the combined action of multiple pharmacodynamic substances. In order to clarify the specific mechanism of zedoary tumeric against liver cancer, this paper first analyzes the mechanism of its single pharmacodynamic substance against liver cancer, and then verifies the joint anti liver cancer mechanism of its "pharmacodynamic group". By searching the research on the anti hepatoma effect of active components of zedoary tumeric in recent years, we found that pharmacodynamic substances, including curcumol, zedoarondiol, curcumenol, curzerenone, curdione, curcumin, germacrone, β-elemene, can act on multi-target and multi-channel to play an anti hepatoma role. For example, curcumin can regulate miR, GLO1, CD133, VEGF, YAP, LIN28B, GPR81, HCAR-1, P53 and PI3K/Akt/mTOR, HSP70/TLR4 and NF-κB. Wnt/TGF/EMT, Nrf2/Keap1, JAK/STAT and other pathways play an anti hepatoma role. Network pharmacological analysis showed that the core targets of the "pharmacodynamic group" for anti-life cancer are AKT1, EGFR, MAPK8, etc, and the core pathways are neuroactive live receiver interaction, nitrogen metabolism, HIF-1 signaling pathway, etc. At the same time, by comparing and analyzing the relationship between the specific mechanisms of pharmacodynamic substance and "pharmacodynamic group", it is found that they have great reference significance in target, pathway, biological function, determination of core pharmacodynamic components, formation of core target protein interaction, in-depth research of single pharmacodynamic substance, increasing curative effect and so on. By analyzing the internal mechanism of zedoary tumeric pharmacodynamic substance and "pharmacodynamic group" in the treatment of liver cancer, this paper intends to provide some ideas and references for the deeper pharmacological research of zedoary tumeric and the relationship between pharmacodynamic substance and "pharmacodynamic group".  相似文献   
3.
现代中药学研究常将中药药效成分定义为次生代谢产物,对相关化学成分的提取分离、活性及质量标准研究较多,在制药过程中蛋白质、糖类、酯类等多被认为是杂质,这是受到了天然药物化学研究思路的影响。随着人类对中医药基础研究的深入,越来越多的研究发现营养成分往往也具有一定的活性。仍将目光聚焦于中药次生代谢产物的研究思路是否有局限,蛋白质、糖类、酯类等是否也应纳入活性研究及质量控制的范畴?通过整理中药中蛋白质、油脂等各类营养物质成分的研究现状,梳理中药部分营养物质具有的药理、生理活性,反思中医药现代研究方面的发展路径,对中医药营养成分在质量控制、研究方向及医养领域发展提出一些建议,对中医药在中药营养活性方面进行初步探究。  相似文献   
4.
采用液相色谱-质谱(LC-MS)联用技术研究他克莫司的有关物质。采用Agilent Eclipse Plus-C18(150 mm × 4.6 mm,3.5 μm)色谱柱,以0.01%甲酸水溶液-乙腈-甲基叔丁基醚为流动相体系,对他克莫司及其强制降解试验样品中的有关物质进行梯度洗脱分离;电喷雾正离子化-四极杆-飞行时间串联质谱法(ESI-Q-TOF/MS)测定各有关物质的母离子及碎片离子的准确质荷比和元素组成,并解析鉴定有关物质的结构。在所建立的条件下,他克莫司与其有关物质分离良好,检测并鉴定出35个主要有关物质,其中2个分别为他克莫司的互变异构体Ⅰ和Ⅱ(他克莫司的有效成分),3个为美国药典收载的已知杂质,其余30个为新鉴定的未知有关物质。研究结果可为他克莫司发酵生产过程的质量控制提供参考依据。  相似文献   
5.
6.
目的:固相萃取—高效液相色谱法同时测定盐酸帕洛诺司琼注射液中差向异构体、对映异构体、氮氧杂质等6种杂质的含量。方法:样品经1 mol·L-1氢氧化钠溶液调节pH,经Agilent Bond Elut C8固相萃取柱(200 mg,3 mL)去除大部分基质干扰,实现净化与富集,再用乙醇洗脱得到富集物。采用USP40盐酸帕洛诺司琼原料药已知杂质测定方法,以Astec CHIROBIOTIC?誖V(250 mm × 4.6 mm,5 μm)为色谱柱对其进行分离检测。结果:6种杂质在0.2~4.3 μg·mL-1范围内线性良好,相关系数r≥0.999 5,方法的检测限为0.056~0.065 μg·mL-1,低、中、高3个浓度的加样回收率为90.60%~105.7%。结论:本方法可用于同时检测盐酸帕洛诺司琼注射液中的6种杂质。  相似文献   
7.
目的评价国产乳酸环丙沙星滴眼液的质量现状。方法采用现行法定标准检验结合探索性研究结果,对市场上3家企业生产的36批乳酸环丙沙星滴眼液的质量进行比较分析,通过对含量测定、有关物质及抑菌剂合理性等项目的考察,结合稳定性试验,分析不同企业产品的质量差异。结果法定标准检验36批乳酸环丙沙星滴眼液,合格率为100%;探索性研究显示,该品种现行标准多个安全性检查项目缺失、检验方法专属性差、标准不统一。结论国内乳酸环丙沙星滴眼液整体质量一般,现行质量标准有待提高。  相似文献   
8.
目的:建立注射用三磷酸胞苷二钠(CTP-Na2)有关物质检验方法。方法:采用高效液相色谱法,以C18为填充柱,以含反相离子对试剂的磷酸盐缓冲液为流动相[0.02 mol·L^-1磷酸盐缓冲液-乙腈(90∶10)];流速:1.0 mL·min^-1;检测波长:271 nm;柱温:35℃,采用校正因子计算有关物质。结果:CTP-Na 2在0.093~1.860 mg·mL^-1范围内,溶液的浓度与峰面积的线性关系良好,r=0.9997;平均回收率为99.6%(RSD=1.5%,n=9),CTP-Na2对照品溶液在25 h内的稳定性良好(RSD=0.7%);CTP-Na2及主要降解杂质二磷酸胞苷二钠(CDP-Na2)、单磷酸胞苷二钠(CMP-Na2)的方法定量限分别为4.1、2.1、2.8 ng,检出限分别为0.82、0.16、0.22 ng。结论:现行质量标准中有关物质项存在诸多问题,新建的检测方法操作简便、灵敏度高,可用于质量控制。  相似文献   
9.
This paper reports on the identification and full chemical characterization of isotonitazene (N,N‐diethyl‐2‐[5‐nitro‐2‐({4‐[(propan‐2‐yl)oxy]phenyl}methyl)‐1H‐benzimidazol‐1‐yl]ethan‐1‐amine), a potent NPS opioid and the first member of the benzimidazole class of compounds to be available on online markets. Interestingly, this compound was sold under the name etonitazene, a structural analog. Identification of isotonitazene was performed by gas chromatography mass spectrometry (GC–MS) and liquid chromatography time‐of‐flight mass spectrometry (LC‐QTOF‐MS), the latter identifying an exact‐mass m/z value of 411.2398. All chromatographic data indicated the presence of a single, highly pure compound. Confirmation of the specific benzimidazole regio‐isomer was performed using 1H and 13C NMR spectroscopy, after which the chemical characterization was finalized by recording Fourier‐transform (FT‐IR) spectra. A live cell‐based reporter assay to assess the in vitro biological activity at the μ‐opioid receptor (MOR) revealed that isotonitazene has a high potency (EC50 of 11.1 nM) and efficacy (Emax 180% of that of hydromorphone), thus confirming that this substance is a strong opioid. Isotonitazene has not been previously detected, either in powder form, or in biological fluids. The high potency and efficacy of isotonitazene, combined with the fact that this compound was being sold undiluted, represents an imminent danger to anyone aiming to use this powder.  相似文献   
10.
Recent investigations have shown that N‐ethyl‐N‐cyclopropyl lysergamide (ECPLA) produces LSD‐like behavioral effects in mice, which suggests that it may act as a hallucinogen in humans. Although the use of ECPLA as a recreational drug has been limited, key analytical data that can be used to detect ECPLA are required for future forensic and clinical investigations. ECPLA is an isomer of (2′S,4′S)‐lysergic acid 2,4‐dimethylazetidide (LSZ), a lysergamide that emerged as a recreational drug in 2013. Several analytical approaches were examined, including single‐ and tandem mass spectrometry platforms at low and high resolution, gas‐ and liquid chromatography (GC, LC), nuclear magnetic resonance spectroscopy (NMR), and GC condensed‐phase infrared spectroscopy (GC‐sIR). ECPLA and LSZ could be differentiated by NMR, GC‐sIR, GC, and LC‐based methods. The electron ionization mass spectra of ECPLA and LSZ contained ion clusters typically observed with related lysergamides such as m/z 150–155, m/z 177–182, m/z 191–197, m/z 205–208, and m/z 219–224. One of the significant differences in abundance related to these clusters included ions at m/z 196 and m/z 207/208. The base peaks were detected at m/z 221 in both cases followed by the retro‐Diels‐Alder fragment at m/z 292. Minor but noticeable differences between the two isomers could also be seen in the relative abundance of m/z 98 and m/z 41. Electrospray ionization mass spectra included lysergamide‐related ions at m/z 281, 251, 223, 208, 197, 180, and 140. LSZ (but not ECPLA) showed product ions at m/z 267 and m/z 98 under the conditions used.  相似文献   
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