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61.
碳酸钙咀嚼片中辅料单糖醇的高效液相色谱-质谱分析   总被引:2,自引:0,他引:2  
用液相色谱-质谱联用法鉴定了进口碳酸钙咀嚼片中的辅料单糖醇为山梨糖醇,并对其含量进行测定;色谱柱为HypersilNH2(4.6×150mm,5μm),流动相为乙腈-水(体积比80∶20),质谱为检测器,以木糖醇为内标;山梨糖醇的线性范围为10.4~104mg/L,相关系数为0.9996,加标回收率在95%~98%之间;液质联用测定糖醇不需对样品衍生化,方法简便,检测灵敏度高。  相似文献   
62.
A sensitive and simple high-performance liquid chromatographic method with UV detection was developed and validated for the determination of andrographolide in rat whole blood. Carbamazepine was employed as internal standard and the blood sample was extracted with chloroform. Chromatographic separations were achieved on a Chromasil ODS column (250 x 4.6 mm, 5 microm). The mobile phase was consisted of methanol-water (52:48, v/v) and delivered at 0.8 mL/min. The detection wavelength was set at 225 nm. The calibration curve had a good linearity in the range 0.053-530 microg/mL in rat whole blood with its correlation coefficient being 0.996. The extraction recovery of andrographolide was ranged from 65.7 to 72.6%. The intra-day and inter-days repeatabilities were below 4.2% in terms of the percentage of relative standard deviation (RSD). The method was used to provide data on the pharmacokinetics of the drug in rats. The data obtained was processed using the 3P87 pharmacokinetic program. The results showed that the disposition of andrographolide after intravenous administration of liposomal andrographolide conformed to a two-compartment open model with alpha = 4.75 x 10(-2) +/- 2.41 x 10(-3) min(-1), beta = 3.16 x 10(-3) +/- 1.58 x 10(-4) min(-1), V(c) = 174.67 +/- 13.97 mL, k(21) = 1.60 x 10(-2) +/- 8.12 x 10(-4) min(-1), k(10) = 9.38 x 10(-3) +/- 5.62 x 10(-4) min(-1), k(12) = 2.53 x 10(-2) +/- 1.27 x 10(-3) min(-1) and AUC(0-infinity) = 1525.47 +/- 92.35 microg min/mL. For the intragastric administration of andrographolide tablets, the disposition of andrographolide followed a one-compartment open model with k(e) = 6.78 x 10(-3) +/- 3.53 x 10(-4) min(-1), k(a) = 3.69 x 10(-2) +/- 4.68 x 10(-3) min(-1), T(max) = 59.69 +/- 3.61 min, C(max) = 1.62 +/- 0.11 microg/mL, V(c) = 1056.90 +/- 83.42 mL, AUC(0-infinity) = 348.75 +/- 24.41 microg min/mL.  相似文献   
63.
Diclofenac sodium (2-[(2,6-dichlorophenyl)amino]benzeneacetic acid monosodium salt) was investigated as a low-solubility drug and Naklofen® retard prolonged release tablets, containing 100 mg of diclofenac sodium as a prolonged release lipophilic matrix system using factorial design approach. First, the solubility characteristics of diclofenac sodium in aqueous media with various ionic strengths, ionic compositions and pH in the range of 1-8 were determined. The obtained results showed that the solubility of diclofenac sodium depends mainly on pH of the aqueous medium and less on the composition and ionic strength of the medium. Next, the estimation of the effects of six different factors (type of the dissolution apparatus, rotation speeds of the stirring elements, pH, ionic strengths of dissolution medium, the applied salt, and the producer of the on-line connected dissolution apparatus and UV spectrophotometer) on the release of diclofenac sodium, using the two-level six-factorial design was investigated. It was found that rotation speeds of the stirring elements, pH, and ionic strengths of the dissolution medium have a significant impact on the drug release and should be further followed in future drug release analyses. The advantages of the factorial design approach are obvious in this work. It is a very economic way of obtaining the maximum amount of information in a short period of time, especially in the case of prolonged release formulations where each experiment requires at least 24 h.  相似文献   
64.
毛细管电泳法测定复方鱼腥草片中的绿原酸和槲皮素   总被引:8,自引:2,他引:6  
建立了毛细管电泳法分析复方鱼腥草片中绿原酸和槲皮素的方法,通过研究缓冲溶液酸度和浓度、工作电压和进样时间的影响优化了分析条件。在优化的条件下,15min内实现了两种分析物质的良好分离。绿原酸和槲皮素峰高和质量浓度分别在0.05~0.80g/L和0.05~1.00g/L范围内成良好线性。基于迁移时间和峰高的重复性(RSD)分别为:绿原酸,1.91%和4.32%;槲皮素,2.30%和3.18%。绿原酸和槲皮素的检出限(S/N=3)分别为0.014g/L和0.015g/L。通过分析实际样品并做加样回收实验进一步验证了该方法的可行性。  相似文献   
65.
KPCA-聚类分析法和用便携式拉曼仪快速鉴别降糖药   总被引:1,自引:0,他引:1  
对不同种类的降糖药片进行拉曼光谱的核主成分分析(KPCA)-聚类分析,实现快速、简便的鉴别。KPCA可以有效地避免主成分分析(PCA)只能处理线性问题和降维效果不明显的弊端。它通过一个非线性变换,首先将原变量空间映射到高维特征空间,然后在这个高维特征空间中进行线性主成分分析。采集得到的药片拉曼光谱的KPCA-聚类分析结果表明,采用KPCA提取特征变量的聚类结果比采用PCA提取特征变量后进行聚类分析的效果好,并且未经刮除表面包膜的降糖药片识别准确率为96.5%,经过刮除表面包膜处理的降糖药片的识别准确率为100%。便携式拉曼光谱仪结合该方法以其检测速度快、准确率高、使用简便、无样品前处理等显著优势,为药品的快速检验技术提供一种新的有效的鉴别手段。  相似文献   
66.
Shuanghua Baihe tablet is a traditional Chinese patent medicine which showed special advantages in the treatment of recurrent aphthous stomatitis. Scientists have improved and implemented the LC-MS/MS method, which is specific and sensitive, for comparative pharmacokinetics study of five alkaloids, including palmatine, berberine, epiberberine, jatrorrhizine and coptisine in rat plasma after oral administration of Rhizoma Coptidis extract and Shuanghua Baihe tablets. The results showed that Shuanghua Baihe tablets could promote the absorption of these five alkaloids and improved their bioavailability compared with R. Coptidis extract. To further investigate the related mechanism, everted intestinal sac model in vitro was used to indicate that alteration of in vivo pharmacokinetics of five alkaloids could be attributed to, at least in part, the absorption changes by coadministration of other herbs. These discoveries served as a theoretical basis for clinical use of Shuanghua Baihe tables.  相似文献   
67.
Mang‐Guo‐Zhi‐Ke tablets (MGZKTs) is an effective Chinese patent medicine. It contains mango leaf extract as the main raw material and the antihistamine drug, chlorpheniramine maleate is included in the formulation. However, its pharmacokinetic effect is rarely reported. A highly sensitive, reliable and rapid high‐throughput method using ultra‐high‐performance liquid chromatography with tandem mass spectrometry (UHPLC‐MS/MS) was used to simultaneously determine kaempferol, quercetin, mangiferin, p‐hydroxybenzoic acid, gallic acid and chlorpheniramine maleate in rat plasma after oral administration of MGZKTs. The method was successfully developed and fully validated to investigate the pharmacokinetics of MGZKTs. Chloramphenicol and clarithromycin were used as internal standards (IS). A practicable protein precipitation procedure with methanol was adopted for sample preparation. The samples were separated on an Acquity UHPLC Syncronis C18 column (100 × 2.1 mm, 1.7 μm) using 0.1% formic acid–acetonitrile as the mobile phase. The flow rate was set at 0.4 mL/min. The obtained calibration curves were linear in the concentration range of ~1–1000 ng/mL for plasma (r > 0.99). Method validation results met the criteria reported in the US Food and Drug Administration guidelines. Quercetin, p‐hydroxybenzoic acid and kaempferol were absorbed rapidly and reached the peak concentration between 0.16 and 0.25 h. This validated that the UHPLC‐MS/MS method was successfully applied to study the pharmacokinetic parameters of the six compounds in rat plasma after oral administration of MGZKTs. This evidence will be useful for the clinical rational use of Mang‐Guo‐Zhi‐Ke tablets.  相似文献   
68.
Oral insulin administration still represents a paramount quest that almost a century of continuous research attempts did not suffice to fulfill. Before pre-clinical development, oral insulin products have first to be optimized in terms of encapsulation efficiency, protection against proteolysis, and intestinal permeation ability. With the use of dendritic mesoporous silica nanoparticles (DMSNs) as an insulin host and together with a protein-based excipient, succinylated β-lactoglobulin (BL), pH-responsive tablets permitted the shielding of insulin from early release/degradation in the stomach and mediated insulin permeation across the intestinal cellular membrane. Following an original in vitro cellular assay based on insulin starvation, direct cellular fluorescent visualization has evidenced how DMSNs could ensure the intestinal cellular transport of insulin.  相似文献   
69.
《Analytical letters》2012,45(17):2653-2662
A gradient reversed-phase high performance liquid chromatography (RP-HPLC) method was developed for separation and quantitation of impurities in pharmaceutical dosage form of ofloxacin tablets. The developed method was a stability indicating test method for estimation of related impurities generated during synthesis, formulation, and storage of ofloxacin tablets. Forced degradation studies were performed on ofloxacin tablets including acid hydrolysis (5.0 M hydrochloric acid), base hydrolysis (5.0 M sodium hydroxide), oxidation (30% hydrogen peroxide), heat (105°C) humidity degradation 25°C/92% RH/119 b & 40 min, and photolytic degradation (2600 Lux/119 h & 40 min). From the degradation study, the degradation was found between 0–15%. Limit of detection and limit of quantification were established in terms of percentage for all potential impurities. The recovery studies were conducted on finished dosage samples (tablets) for all potential impurities and the average percentage recovery was ranged from 90.8 to 104.2. Placebo interference was verified by taking the placebo (composition of excipients) equivalent to weight in portion of test preparation and no interference was observed. The method was validated and found to be linear, accurate, precise, specific, robust, and reliable. The developed method was established in accordance to ICH guidelines.  相似文献   
70.
Senecio scandens as a commonly used traditional Chinese medicine that is used alone or in combination with other herbs in preparations such as QianBai BiYan tablets has attracted much attention because of its hepatotoxic pyrrolizidine alkaloids. Nowadays, most studies for pyrrolizidine alkaloids are only performed on herbs or a preparation, however, production of preparations is a dynamic process, control of toxic impurities for raw materials, or finished products cannot monitor the production process dynamically. Thus, in this study, qualitative and quantitative analysis of pyrrolizidine alkaloids for the entire process quality control from S. scandens to its preparations was carried out with HPLC‐MS/MS for the first time, which was more comprehensive and dynamic than the previous single‐layer analysis. First, the species of pyrrolizidine alkaloids in S. scandens were analyzed, and the characteristic fragmentation rules of pyrrolizidine alkaloids containing common parent nucleus were found, which can be used to identify these components rapidly in the future. Then, a quantitative method for S. scandens to QianBai BiYan tablets and other nine S. scandens‐containing preparations was established, and after the medication safety speculation, all of them met the relevant safety requirements. After that, in order to ensure the stability and controllable of drug quality, the limit of pyrrolizidine alkaloids in preparations was determined according to the safe dosage that is stipulated to be the same as raw materials. Finally, the factors causing the content change of pyrrolizidine alkaloids in S. scandens from different source were studies, which can provide theoretical basis for selecting suitable raw materials for production.  相似文献   
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