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71.
Krishna Rao Vankalapati Pallavi Alegete Sathyanarayana Boodida 《Biomedical chromatography : BMC》2022,36(7):e5384
A simple, precise, and rapid stability-indicating reversed-phase-HPLC method was developed and validated for the estimation of metformin (MET), dapagliflozin (DAP), and saxagliptin (SAX) combination in bulk and tablet dosage forms. The proposed method uses a Kromasil C18 column (150 × 4.6 mm, 5 μm) with column oven temperature of 30°C and mobile phase containing a mixture of 60% phosphate buffer (pH = 3) and 40% acetonitrile. The flow rate was set at 1.0 mL/min, and the injection volume was 10 μL. The detection was carried out at 230 nm using a photodiode array detector, and the total run time was 4 min. The proposed method was validated according to International Council for Harmonisation (ICH) guidelines for specificity, linearity, precision, accuracy, robustness, and solution stability. The method is linear over the range of 125–750 μg/mL for MET, 1.25–7.5 μg/mL for DAP, and 0.625–3.75 μg/mL for SAX. The observed correlation coefficients (R2) for MET, DAP, and SAX are >0.999. The proposed method is precise, and the percentage relative standard deviation was found to be between 0.4 and 0.8. The observed percentage recoveries were between 98.51 and 100.80 for all three compounds. The product was subjected to stress conditions of acid, base, oxidative, thermal, and photolytic degradation. The product was found to degrade significantly in oxidative, acid, and base hydrolysis degradation conditions, and the degradation products were well determined from the active peaks, thus proving the stability-indicating power of the method. The developed and validated stability-indicating reversed-phase-HPLC method was appropriate for quantitative determination of these drugs in pharmaceutical preparations and also for quality control in bulk manufacturing. 相似文献
72.
Tayebeh Asadi Nader Rahimi Kakavandi Amir Nili Ahmadabadi Ali Heshmati Akram Ranjbar Khosrou Abdi Maryam Ezoddin 《Biomedical chromatography : BMC》2022,36(5):e5304
An effervescent tablet-assisted switchable polarity solvent–based homogeneous liquid-phase microextraction combined with gas chromatography with flame ionization detection has been conducted for the separation, preconcentration, and detection of permethrin and deltamethrin in the river water specimens. Triethylamine (TEA) was utilized as the switchable polarity solvent in this method. The switching process was carried out by the dissolution of an effervescent tablet including an effervescency agent (sodium carbonate) and a proton donor agent (citric acid). Changing the pH of the specimen solution enhanced the conversion of TEA into protonated triethylamine carbonate through the tablet that generated carbon dioxide bubbles in situ. Finally, the addition of sodium hydroxide changed the ionization state of TEA and separated the two phases. Influential factors in the extraction were investigated. According to optimal situations, the limit of detection and the limit of quantification were 0.16 and 0.5 μg L−1 for permethrin and 0.03 and 0.1 μg L−1 for deltamethrin, respectively. The preconcentration factor was 194 in river water samples and inter- and intra-day precision (relative standard deviation %; n = 5) was <5%. The extraction recovery was obtained in the range of 93.0%–97% for permethrin and deltamethrin in water samples. 相似文献
73.
《Biomedical chromatography : BMC》2017,31(10)
Losartan and tripterygium glucoside tablet (TGT) are often simultaneously used for reducing urine protein excretion in clinic. However, it is unknown whether there is potential herb–drug interaction between losartan and TGT. The aim of this study was to investigate their potential herb–drug interaction, and clarify the mechanism of the effect of TGT on the pharmacokinetics of losartan and its metabolite EXP3174 in rats. The plasma concentrations of losartan and EXP3174 were determined by LC–MS, and the main pharmacokinetic parameters were calculated. The C max, t 1/2 and AUC(0–t ) of losartan became larger after co‐administration, while the C max and AUC(0–t ) of EXP3174 became smaller, suggesting that TGT could influence the pharmacokinetics of losartan and EXP3174. The effects of TGT and its main components on the metabolic rate of losartan were further investigated in rat liver microsomes. Results indicated that TGT and its two main ingredients could decrease the metabolic rate of losartan. Therefore, it was speculated that TGT might increase the plasma concentration of losartan and decrease the concentration of EXP3174 by inhibiting the metabolism of losartan. The results could provide references for clinical medication guidance of losartan and TGT to avoid the occurrence of adverse reactions. 相似文献
74.
Hideyuki Shinzawa Kimie Awa Takehiro Okumura Shin-ichi Morita Makoto Otsuka Yukihiro Ozaki Hidetoshi Sato 《Vibrational Spectroscopy》2009,51(1):125-131
Chemical properties of active substances and insoluble excipient within tablets such as crystalline structures can be seen as an important index for solubility of ingredients. Spectroscopic imaging can potentially be a solid solution to understanding mechanisms at the molecular level and it may bring useful insight in terms of process analytical technique. In the present study, generalized two-dimensional (2D) correlation spectroscopy is utilized for the Raman image analysis of pharmaceutical tablets to reveal molecular interactions between chemical components. By using a spatial distance as a perturbation variable in 2D correlation scheme, synchronous and asynchronous correlation analysis becomes possible. Two kinds of pharmaceutical tablets, pentoxifylline (PTX) as an active substance and palmitic acid (PA) as an insoluble excipient, are prepared with different grinding times, 0.5 and 45 min. The 2D correlation analysis of Raman images of the tablets clearly reveals both physical and chemical effects of grinding process on the properties of the tablets. Asynchronous correlations indicate that a specific molecular structural change of PTX related to the crystallinity is induced by the grinding process. Namely, the crystallinity of PTX based on CH2 structure is a key factor to control the solubility of the tablets. Some properties of pharmaceutical tablets, i.e. solubility or distribution of components in turn may become possible by the simple grinding process. Detailed analysis of Raman images becomes possible by the 2D correlation spectroscopy. 相似文献
75.
76.
《Analytical letters》2012,45(12):1933-1941
Abstract A rapid and simple flow‐injection chemiluminescence (CL) method is described for the determination of perphenazine, which is based on the CL intensity that generated from the redox reaction of Ce (IV)-perphenazine in HNO3 medium is proportional to the perphenazine concentration without any sensitizers. The proposed method allows the determination range within 1.0×10?7–7.0 ×10?5 g mL?1 with a detection limit of 8.0×10?8 g mL?1, and it has been successfully applied to the determination of the perphenazine in pharmaceutical tablet compared well with the official method. 相似文献
77.
建立了毛细管电泳-电喷雾电离质谱联用法同时测定清肺抑火片中苦参碱、药根碱、氧化苦参碱、栀子苷4种药效成分含量的分析方法.采用未涂层石英毛细管,以35 mmol/L乙酸铵(含20%乙腈,pH=6.5)为缓冲溶液、60%异丙醇(含3.3 mmol/L乙酸)为鞘液,分离电压为28 kV时,各组分在11 min内达到基线分离.苦参碱、药根碱、氧化苦参碱、栀子苷的线性范围分别为0.030~150 mg/L、0.060~20 mg/L、0.060~80 mg/L、0.60~300mg/L,检出限分别为0.010、0.020、0.020、0.20mg/L.样品的加标回收率在91.0%~107%之间,相对标准偏差均小于4.9%.方法简便、快速、灵敏度高,已成功用于清肺抑火片中的苦参碱、药根碱、氧化苦参碱、栀子苷含量的同时测定. 相似文献
78.
79.
本文采用双波长薄层扫描仪,以紫外吸收方式,测定了感冒通片中扑尔敏的含量,其测定波长λs=260nm,参比波长λR=320nm,所用薄层板为GF254,薄层厚度为0.4mm,展开剂为苯∶氯仿∶冰HAC∶甲醇=5∶5∶0.5∶0.6,回收率为101.6%。 相似文献
80.
应用毛细流自组装成环荧光显微成像技术,建立了溴化十六烷基三甲胺(Cet yhrimet hylammonium bromide,CTMAB)-Al3+ -氧氟沙星(Ofloxacin,OFLX)三元荧光体系(CTMAB-Al3+ -OFLX)测定氧氟沙星的方法,并实测鸡灌喂氧氟沙星药片后血液中药物浓度、人体尿液中氧氟沙... 相似文献