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121.
溶剂浮选法分离富集大黄中的有效成分 总被引:1,自引:0,他引:1
采用溶剂浮选法对大黄提取液中的芦荟大黄素、大黄素、大黄酚以及大黄素甲醚进行了分离富集,并用高效液相色谱法分别测定了其含量。考察了料液浓度、浮选溶剂、浮选时间、浮选液pH值、氮气流速和电解质NaCl浓度对浮选效率的影响,并与泡沫浮选法和溶剂萃取法进行了比较。结果表明:溶剂萃取效果最差,泡沫浮选次之,溶剂浮选法分离富集效果最好。当料液浓度为6.4mg/mL,浮选时间为30min,浮选液pH一1~2,氮气流速为20mL/min,电解质NaCl浓度为0.4mol/L时,溶剂浮选效率最佳。 相似文献
122.
利用化学计量学分辨方法和高效液相色谱法建立了黄芪中毛蕊异黄酮和芒柄花素的定量分析方法。色谱柱为Hypersic ODS柱(4.4mm×250mm,5μm),流动相为A:水含0.2%(V/V)醋酸,B:乙腈含0.2%(V/V)醋酸,线性梯度洗脱。借直观推导式演进特征投影(HELP)法分辨HPLC-DAD产生的二维数据得毛蕊异黄酮和芒柄花素的纯光谱和纯色谱,用总体积积分法定量分析其含量。毛蕊异黄酮和芒柄花素的校准曲线和相关系数分别为y=166.72x+127.8(r=0.9997)和y=178.39x+187.2(r=0.9993),线性范围分别为1.0—116.5μg·mL-1和1.2—112.5μg·mL-1,加标回收率分别在96.5%—98.7%和96.8%—98.5%之间。方法灵敏、选择性和可靠性好,可用于测定黄芪中毛蕊异黄酮和芒柄花素含量及质量控制。 相似文献
123.
Hongmin Zhang Xintong Hu Miao Qiao Yang Li Shijie Cao Liqin Ding Xinchi Feng Ning Kang Deqin Zhang Feng Qiu 《Journal of separation science》2019,42(16):2592-2601
A rapid and sensitive liquid chromatography with tandem mass spectrometry method was developed and validated for simultaneous determination of puerarin, daidzin, daidzein, 3′‐hydroxy puerarin, and genistein in rat plasma after oral administration of Puerariae lobatae radix extract. The method of protein precipitation with acetonitrile was used for sample preparation. Chromatographic separation was achieved on a C18 column with the mobile phases of acetonitrile/water containing 0.1% formic acid. The analytes were detected by mass spectrometer with an electrospray ionization source operating in the negative ion mode. The linearity, precision, accuracy, dilution reliability, recovery, matrix effects, and stability of the method were within acceptable ranges. The developed method was successfully used to compare the pharmacokinetic characteristics of five analytes in normal and type 2 diabetics rats after oral administration of Puerariae lobatae radix extract. Several pharmacokinetic alterations were observed and this might be caused by the pathological state of type 2 diabetes. 相似文献
124.
桔梗等中药微量元素初探 总被引:5,自引:0,他引:5
对中药桔梗、怀牛膝,华山参、鹿角胶,龟甲胶及阿胶进行了微量元素研究。结果发现:同一种中药因产地不同,其微量元素的含量不同。同一种植物药,其部位不同,所含微量元素多少不等。同一类型的中药,其品种、来源不同,微量元素的含量高低也不相同。本研究为今后对这些中药进行真伪鉴别,合理开发或综合利用都提供了科学的依据。 相似文献
125.
A capillary electrophoretic method for simultaneous determination of six bioactive ingredients (berberine, palmatine, baicalin, sennoside B, emodin, and sennoside A) in the Chinse herbal formula San-huang-hsieh-hsin-tang was established. A carrier composed of aqueous buffer solution (50 mM sodium cholate, 15 mM sodium dihydrogen phosphate, and 4.25 mM sodium borate)-acetonitrile (3:2) was found to be the most suitable electrolyte for this separation. Contents of these constituents in a non-pretreated methanol-water extract of San-huang-hsieh-hsin-tang sample could be easily determined within 20 min. The effects of borate, cholate, and organic modifier (acetonitrile) concentration of the carrier on the migration behavior of the solutes were also studied. 相似文献
126.
Characterization of the constituents in rat plasma after oral administration of radix polygoni multiflori extracts by ultra‐performance liquid chromatography/quadrupole time‐of‐flight mass spectrometry 下载免费PDF全文
Longfei Lin Hongmei Lin Xingbin Yin Yang Zhao Zhenwen Xia Miao Zhang Xuechun Li Jing Han Changhai Qu Jian Ni 《Biomedical chromatography : BMC》2015,29(10):1541-1547
An ultra‐performance liquid chromatography/quadrupole time‐of‐flight mass spectrometry method was established to detect as many constituents in rat plasma as possible after oral administration of Radix polygoni multiflori (RPM) extract. A C18 column (150 × 2.0 mm, 4 µm) was adopted to separate the samples, and mass spectra were acquired in negative modes. The fingerprints of RPM extract were established, resulting in 39 components being detected. Among these compounds, 29 were identified by comparing the retention times and mass spectral data with those of reference standards and relevant references, and eight compounds were separated and detected in RPM for the first time. In vivo, 23 compounds were observed in dosed rat plasma, 16 of 23 compounds were indicated as prototype components of RPM, and seven compounds were predicted to be metabolites of RPM. A high‐speed and sensitive method was developed and was successfully utilized for screening and characterizing the ingredients and metabolites of RPM. Copyright © 2015 John Wiley & Sons, Ltd. 相似文献
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129.
苦黄注射液中大黄蒽醌含量测定方法改进 总被引:2,自引:0,他引:2
按苦黄注射液原质量标准(草案)中测定方法,大黄蒽醌用氯仿提取,阴性试验结果为苦黄注射液大黄蒽酯标示量的16.50%(n=5),结果偏高;改用石油醚提取,降为6.15%,重复性试验的RSD为1.44%(n=5),加标回收率为101.8%(n=5),显色在1-4h内稳定,表明该法是可行的。 相似文献
130.