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51.
邓老凉茶颗粒的超高效液相色谱质谱联用指纹图谱研究   总被引:1,自引:0,他引:1  
建立了适用于邓老凉茶颗粒质量控制的超高效液相色谱质谱联用指纹图谱分析方法。样品采用甲醇索氏萃取60 min,萃取液采用超高效液相色谱质谱法进行指纹图谱分析。色谱柱采用Waters ACQUITY HSST3 C18(150 mm×3.0 mm,1.8μm),以0.5%甲酸-乙腈为流动相进行梯度洗脱,流速为0.8 mL/min,柱温35℃。质谱采用负离子ESI模式,选择基峰离子流质量色谱图进行指纹图谱研究。32个共有峰在15 min内得到良好分离,其中15个共有峰通过对照品进行了确证。通过《中药色谱指纹图谱相似度评价系统2004A版》对邓老凉茶颗粒样品进行相似度分析,15个批次样品的相似度均达到0.960以上,表明邓老凉茶颗粒的产品质量稳定性很好。以32个共有峰的相对峰面积进行主成分分析,邓老凉茶颗粒样品之间的细微质量差异得到明显区分。该方法快速、高效、可靠,可有效地用于邓老凉茶颗粒的质量控制。  相似文献   
52.
Wenxin granule (WXG) is a popular traditional Chinese medicine (TCM) preparation for the treatment of arrhythmia disease. Potent analytical technologies are needed to elucidate its chemical composition and assess the quality differences among multibatch samples. In this work, both a multicomponent characterization and quantitative assay of WXG were conducted using two liquid chromatography–mass spectrometry (LC-MS) approaches. An ultra-high performance liquid chromatography–ion mobility quadrupole time-of-flight mass spectrometry (UHPLC/IM-QTOF-MS) approach combined with intelligent peak annotation workflows was developed to characterize the multicomponents of WXG. A hybrid scan approach enabling alternative data-independent and data-dependent acquisitions was established. We characterized 205 components, including 92 ginsenosides, 53 steroidal saponins, 14 alkaloids, and 46 others. Moreover, an optimized scheduled multiple reaction monitoring (sMRM) method was elaborated, targeting 24 compounds of WXG via ultra-high performance liquid chromatography–triple quadrupole linear ion trap mass spectrometry (UHPLC/QTrap-MS), which was validated based on its selectivity, precision, stability, repeatability, linearity, sensitivity, recovery, and matrix effect. By applying this method to 27 batches of WXG samples, the content variations of multiple markers from Notoginseng Radix et Rhizoma (21) and Codonopsis Radix (3) were depicted. Conclusively, we achieved the comprehensive multicomponent characterization and holistic quality assessment of WXG by targeting the non-volatile components.  相似文献   
53.
A sensitive and validated method of liquid chromatography–tandem mass spectrometry (LC–MS/MS) was established to test the plasma concentrations of active ingredients in Qinxing Qingre Zhike Granule, namely geniposide, liquiritin, isoliquiritin, baicalin, wogonoside, baicalein, liquiritigenin, isoliquiritigenin and glycyrrhetinic acid. The analysis was performed on an Ultimate XB‐C18 column at the flow rate of 0.4 mL min?1 in a single run of 18 min. The mobile phase was composed of 0.05% formic acid in water and acetonitrile with gradient elution. Positive and negative scanning and selected multiple reaction monitoring modes were applied for quantization. The proposed method showed good linearity in the given ranges from 0.6800–340.0 to 3.920–1960 ng mL?1 with r2 > 0.9917 for all the analytes. The precision (RSD) was no more than 12%, and the accuracy (RE) was less than ±11% for intra‐ and inter‐day. The extract recovery and matrix effect were acceptable for the requirements of biological sample analysis. Moreover, the developed method was effectively applied to the pharmacokinetic investigation of Qinxing Qingre Zhike Granule after oral administration in rats.  相似文献   
54.
Tianma‐Gouteng granule (TGG), a Chinese herbal formula preparation, is clinically used for the treatment of cardio‐cerebrovascular diseases such as hypertension, cerebral ischaemia, acute ischaemic stroke and Parkinson's disease. Although few reports have been published concerning the absorbed prototype components of TGG, the possible metabolic pathways of TGG in vivo remain largely unclear. In this study, a method using UPLC–Q/TOF MS was established for the detection and identification of the absorbed prototype components and related metabolites in rat plasma and bile after oral administration of TGG at high and normal clinical dosages. A total of 68 components were identified or tentatively identified in plasma and bile samples, including absorbed prototypes and their metabolites. The major absorbed components were gastrodin, isorhynchophylline, rhynchophylline, isocorynoxeine, corynoxeine, geissoschizine methyl ether baicalin, baicalein, wogonoside, wogonin, geniposidic acid, leonurine, 2,3,5,4′‐tetrahydroxystilbene‐2‐Oβ‐d ‐glucoside and emodin. The main metabolic pathways of these components involved phase I (isomerization, hydrolysis and reduction) and phase II (glucuronidation and sulfation) reaction, and the phase II biotransformation pathway was predominant. The present study provides rich information on the in vivo absorption and metabolism of TGG, and the results will be helpful for further studies on the pharmacokinetics and pharmacodynamics of TGG.  相似文献   
55.
Although an atherosclerosis (AS) model using low‐density lipoprotein receptor deletion mice has been widely applied, its pathological pathway in metabolite level is still not clear. To further reveal the metabolite profile and identify the potential biomarkers in AS development, a serum metabolomic approach was developed based on reversed‐phase liquid chromatography/quadrupole time‐of‐flight mass spectrometry (LC‐Q‐TOF‐MS). The established metabolomic platform was also used for elucidating the therapeutic mechanism of a traditional Chinese medicine named Sishen granule (SSKL). Twenty‐one potential biomarkers in AS mouse serum were identified. Through functional analysis of these biomarkers, inflammation, proliferation, dysfunction of energy metabolism and amino acid metabolism were considered the most relevant pathological changes in AS. DNA damage products were found for the first time in the metabolomic study of AS. The network established by 20 biomarkers revealed that pyruvate metabolism, citrate cycle, fatty acid metabolism and urea metabolism were seriously disturbed. This metabolomic study not only supplied a systematic view of the progression of AS but also provided a theoretical basis for the treatment of AS. This metabolomic study also demonstrated that SSKL had therapeutic effectiveness for AS through partly reversing the inflammation reaction and amino acid metabolism dysfunction. Copyright © 2015 John Wiley & Sons, Ltd.  相似文献   
56.
声空化场下单相对流传热的实验研究   总被引:5,自引:0,他引:5  
以水、乙醇和丙酮为工质,首次通过实验研究了声空化场的热效应、单相对流换热受空化时间.纳米颗粒和实验工质的影响及恒热流密度下单相对流换热系数随声空化强度的变化,并就其强化传热机理进行了分析。  相似文献   
57.
Owing to their extremely high specific surfaces and their high surface-to-volume ratios nanosized ceramic powders show a strong tendency to agglomeration and poor flowability. For improved properties of these powders during storage, transport and shaping a granulation step is necessary. However, the granules must be completely destroyed during dry pressing or redispersion; otherwise, the advantages of nanoparticles in comparison to conventional powders will not be realized. Spray freezing is a new granulation technique which combines the advantages of a conventional granulation by spray drying and a sublimation drying process. Different suspensions of nanosized oxide powders were rapidly frozen by spray freezing and subsequently dried by freeze drying. Thus, capillary forces can be excluded by this process. The achieved granulates show spheric granules with very low strength, improved flowability and increased bulk density. They were redispersible and can be destroyed under very low pressures.  相似文献   
58.
Distinct stratified and non‐stratified morphologies were developed in poly(3‐hexylthiophene) (P3HT) and poly(ethylene glycol) (PEG)‐based homopolymer blends and diblock and triblock copolymer systems. By applying X‐ray photoelectron spectroscopy, only a double‐percolation mechanism including assembling of P3HT chains into the nanofibers in solution aging process with a marginal solvent like p‐xylene as well as crystallization of PEG phase in the cast thin films resulted in vertical stratification and networked fibrils. In cast thin films whose PEG phase, due to low molecular weight or being constrained between two rigid P3HT blocks in triblock copolymers was not crystallized, a non‐stratified discrete fibrillar morphology was acquired. Crystallization of PEGs in the thin films mainly participated in networking and expelling pre‐organized P3HT fibrils to the film surface. By performing the solution aging step in a good solvent such as o‐dichlorobenzene, the P3HTs remained in a coily‐like conformation, and casting the corresponding thin films reflected the non‐stratified discrete granular and featureless morphologies. Assembling the P3HT chains in the presence of PEG phase in cast films at most led to the low‐crystalline granules instead of highly crystalline nanofibrils. No significant crystallization in either homopolymer blends or block copolymer systems conduced to a featureless morphology with homogeneous distribution of existed materials. The surface morphology and ordering in various morphologies were studied employing atomic force microscopy, grazing incidence X‐ray diffraction, and ultraviolet–visible analyses. Copyright © 2016 John Wiley & Sons, Ltd.  相似文献   
59.
A method incorporating double‐wavelength ultra high performance liquid chromatography with quadrupole time‐of‐flight mass spectrometry was developed for the investigation of the chemical fingerprint of Ganmaoling granule. The chromatographic separations were performed on an ACQUITY UPLC HSS C18 column (2.1 × 50 mm, 1.8 μm) at 30°C using gradient elution with water/formic acid (1%) and acetonitrile at a flow rate of 0.4 mL/min. A total of 11 chemical constituents of Ganmaoling granule were identified from their molecular weight, UV spectra, tandem mass spectrometry data, and retention behavior by comparing the results with those of the reference standards or literature. And 25 peaks were selected as the common peaks for fingerprint analysis to evaluate the similarities among 25 batches of Ganmaoling granule. The results of principal component analysis and orthogonal projection to latent structures discriminant analysis showed that the important chemical markers that could distinguish the different batches were revealed as 4,5‐di‐O‐caffeoylquinic acid, 3,5‐di‐O‐caffeoylquinic acid, and 4‐O‐caffeoylquinic acid. This is the first report of the ultra high performance liquid chromatography chemical fingerprint and component identification of Ganmaoling granule, which could lay a foundation for further studies of Ganmaoling granule.  相似文献   
60.
建立了适用于王老吉广东凉茶颗粒质量控制的超高效液相色谱指纹图谱分析方法。样品采用甲醇超声萃取30 min,萃取液用超高效液相色谱法进行指纹图谱分析。色谱柱采用Waters ACQUITY HSS T3 C18(3.0mm×150 mm,1.8μm),以0.5%甲酸-乙腈为流动相进行梯度洗脱,流速为0.8 mL/min,柱温35℃。28个共有峰在18 min内得到良好分离,通过对照品对其中4个峰进行了确证。对王老吉广东凉茶颗粒样品进行了相似度分析,23个批次样品的相似度均达到0.95以上;以28个共有峰的相对峰面积进行主成分分析,23批次样品均落在同一区域。相似度评价和主成分分析结果均表明,王老吉广东凉茶颗粒的产品质量稳定性好。该方法快速、高效、稳定,可用于王老吉广东凉茶颗粒的质量控制。  相似文献   
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