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101.
Gastrodia Rhizoma is a Traditional Chinese Medicine applied in the treatment of stroke, numbness of limb, headache and dizziness. However, its clinical effect is threatened by sulfur‐fumigation used in the process of storage. This article employs content determination coupled with high‐performance liquid chromatography fingerprint to investigate the effect of sulfur‐fumigation on Gastrodia Rhizoma so as to evaluate the quality of Gastrodia Rhizoma. The result was that most active ingredient in Gastrodia Rhizoma decreased after sulfur‐fumigation and the fingerprints analyzed by mathematical statistics between sulfur‐fumigated Gastrodia Rhizoma and unfumigated Gastrodia Rhizoma have substantial differences, which reveals that sulfur‐fumigation has a significant influence on the quality of Gastrodia Rhizoma. The conclusion of hierarchical clustering analysis, principal component analysis and partial least squares could validate each other, which implies that the method of mathematical statistics applied for assessing the quality of Gastrodia Rhizoma is effective and stable. The method not only affords a viable strategy for distinguishing Gastrodia Rhizoma whether sulfur‐fumigated or not and assessment of the quality of Gastrodia Rhizoma, but also provides a reference for other herbal medicine that suffers from sulfur‐fumigation.  相似文献   
102.
103.
Rhizoma Atractylodes Macrocephala (RAM) is an important traditional Chinese medicinal herb that is used for treatment of dyspepsia and anorexia. The active ingredients, atractylenolide I (AO‐I) and atractylenolide III (AO‐III), were identified by direct‐injection ion trap‐mass spectrometry (IT‐MS) for collecting MSn spectra. The major fragment ions of AO‐I and AO‐III were confirmed by MSn both in negative ion mode and in positive ion mode. The possible main cleavage pathway of fragment ions was studied. The determinations of AO‐I and AO‐III were accomplished by liquid chromatography (LC) with UV and MS. The analytes provided good signals corresponding to the protonated molecular ions [M + H]+ and product ions. The precursor ions and product ions for quantification of AO‐III and AO‐I were m/z 249 → 231 and m/z 233 → 215, respectively, using selected ion monitoring by LC‐IT‐MS. Two methods were evaluated for a number of validation characteristics (repeatability, limit of detection, calibration range, and recovery). MS provides a high selectivity and sensitivity for determination of AO‐III and AO‐I in positive mode. After optimization of the methods, separation, identification and quantification of the two components in RAM were comprehensively tested by HPLC with UV and MS. Copyright © 2012 John Wiley & Sons, Ltd.  相似文献   
104.
This study was conducted to investigate the chemical differences between Acori Tatarinowii Rhizoma and Acori Calami Rhizoma using gas chromatography with mass spectrometry and chemometric methods. Quantitative fingerprints were established. A total of 90 volatile compounds were identified and quantified using heuristic evolving latent projection and retention index. An efficient model based on partial least squares‐discriminant analysis coupled with variable iterative space shrinkage approach was developed to distinguish Acori Tatarinowii Rhizoma from Acori Calami Rhizoma. The correct rate was 95.83%, and the area under the receiver operating characteristic curve was 100%. Finally, three volatiles, namely, camphor, longicyclene, and δ‐cadinene, were selected as key discrimination factors between Acori Tatarinowii Rhizoma and Acori Calami Rhizoma. The proposed protocol can serve as a valid strategy for quality control and screening of potential bioactive components of herbal medicines.  相似文献   
105.
半夏淀粉的理化特性   总被引:1,自引:0,他引:1  
研究了不同产地的4种半夏淀粉的理化特性,包括直链淀粉含量、膨胀度、溶解性、持水性、淀粉粒大小和形貌、结晶类型、热特性和糊化特性等。结果表明,这些半夏淀粉中直链淀粉含量为18.60%~23.91%;膨胀度21.53%~23.09%;溶解度11.5%~32.3%;持水性100.3%~119.0%。淀粉粒单粒球形,卵形或圆半球形,直径2~20μm,复粒由2~3个分粒组成,其结晶类型均为C型,结晶度15.0%~37.9%。用差示扫描量热仪测得的转变温度TO、TP和TC分别为71.58~77.75℃、83.03~83.84℃和89.41~90.99℃,热焓为4.316~5.809 J/g。用快速粘度分析仪测定了4种半夏淀粉的糊化特征值:峰值粘度、热糊粘度、冷糊粘度、稀懈值和回复值分别为149.5~226.2、97.7~127.2、141.8~194.3、50.4~99.0和44.2~67.2 RVU。糊化温度77.8~79.9℃,峰值时间8.3~8.7 min。  相似文献   
106.
不同产地莪术挥发油的有效成分   总被引:9,自引:0,他引:9  
用HP6890/5973气相色谱-质谱联用仪分析了四川、福建、浙江产的莪术挥发油的有效成分,结果表明不同产地莪术挥发油的成分差异较大,提示在选择莪术油为原粒制备制剂时要规定产地。  相似文献   
107.
建立了骨碎补药材乙醇和环己烷提取物的高效液相色谱(HPLC)指纹图谱,并利用主成分分析法(PCA)对指纹图谱进行统计分析,以各主要色谱峰的保留时间和峰面积为变量得到score图和loading图。在score图和loading图中,骨碎补的正品和非正品可明显区分,且揭示出对此区分贡献最大的4个潜在指标成分,其中已知成分为柚皮苷、新北美圣草苷和E-4-O-β-D-葡萄糖酰咖啡酸。同时测定了这3种成分在19批正品和非正品骨碎补药材中的含量,其中10批骨碎补药材正品中3种成分的含量为: 柚皮苷6.36~10.1 mg/g,新北美圣草苷5.14~9.21 mg/g,E-4-O-β-D-葡萄糖酰咖啡酸1.87~3.19 mg/g。该方法更全面地反映了药材的化学成分信息,并能从定性和定量两方面控制骨碎补药材的内在质量。  相似文献   
108.
山东不同产地丹参的HPLC指纹图谱-化学模式识别研究   总被引:3,自引:0,他引:3  
建立RPHPLC指纹图谱-化学模式识别评价丹参质量的方法.利用RPHPLC法测定不同产地丹参药材的指纹图谱及丹参酮ⅡAt和丹参酮的含量,采用主成分分析、系统聚类分析和逐步判别分析对指纹图谱信息进行化学模式识别研究.在主成分分析的基础上,以前4个主成分为聚类分析的指标进行系统聚类分析,取阈值为8时,所有样品可被分为4类;并建立了相应的判别函数,回判准确率100%;以此为依据,初步建立了丹参化学模式识别的评价方法.  相似文献   
109.
非水毛细管电泳测定黄连饮片中5种生物碱   总被引:1,自引:0,他引:1  
建立了一种非水毛细管电泳(NACE)同时测定黄连饮片生品与炮制品中小檗碱、巴马汀、药根碱、木兰碱和黄连碱含量的方法。分别考察了非水溶剂、缓冲液体系及其浓度和pH、运行电压、运行温度和检测波长等条件对实验结果的影响。在优化的实验条件下,选择非水毛细管电泳分离模式,以40 mmol/L乙酸钠-40 mmol/L乙酸铵的无水甲醇缓冲溶液(pH 5.8)为电泳介质,未涂渍标准熔融石英毛细管(64.5 cm×75 μm,有效长度56 cm)为分离通道,检测波长为254 nm,分离电压为25 kV,压力进样(5 kPa×6 s),柱温为20 ℃。结果显示,5种生物碱在20 min内可实现基线分离,加标回收率为98.37%~101.03%。该方法简单、准确,重现性较好,可用于黄连饮片内在质量的评价和控制。  相似文献   
110.
The aim of this study was to investigate the influence of compatibility on the contents of main compounds in Paeoniae Radix Alba and Atractylodis Macrocephalae Rhizoma. Ten compounds were separated on an Inertsil ODS‐SP Extend C18 column (250 mm × 4.6 mm, 5 μm) and detected by a diode array detector with the mobile phase consisting of aqueous phosphoric acid (0.1%, v/v; A) and acetonitrile (B) by linear gradient elution. All analytes showed good linearity over a wide concentration range (r2 ≥ 0.9989). The limits of detection and quantification were <8.10 and 10.80 μg/mL, respectively. The intra‐ and interday variations were <4.36%. The average recoveries were observed from 94.90 to 103.38%, with relative standard deviation ranging from 1.23 to 3.15% for the analytes. The established method was reliable enough for global quality evaluation of Paeoniae Radix Alba, Atractylodis Macrocephalae Rhizoma, and their co‐decoctions.  相似文献   
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