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211.
血细胞作为主要的免疫效应细胞在贝类的免疫和防御中有重要作用。本文通过相差显微镜和透射电子显微镜对中华圆田螺(Viviparus chinensis)血细胞的形态与类型以及血细胞对枯草芽孢杆菌的吞噬观察。结果发现壳高4~6 cm的田螺血细胞浓度为(2.17±0.38)×106个/mL。根据血细胞大 相似文献
212.
The volatile compounds emitted from Mosla chinensis Maxim were analyzed by headspace solid‐phase microextraction (HS‐SPME) and headspace liquid‐phase microextraction (HS‐LPME) combined with gas chromatography‐mass spectrometry (GC‐MS). The main volatiles from Mosla chinensis Maxim were studied in this paper. It can be seen that 61 compounds were separated and identified. Forty‐nine volatile compounds were identified by SPME method, mainly including myrcene, α‐terpinene, p‐cymene, (E)‐ocimene, thymol, thymol acetate and (E)‐β‐farnesene. Forty‐five major volatile compounds were identified by LPME method, including α‐thujene, α‐pinene, camphene, butanoic acid, 2‐methylpropyl ester, myrcene, butanoic acid, butyl ester, α‐terpinene, p‐cymene, (E)‐ocimene, butane, 1,1‐dibutoxy‐, thymol, thymol acetate and (E)‐β‐farnesene. After analyzing the volatile compounds, multiple linear regression (MLR) method was used for building the regression model. Then the quantitative structure‐retention relationship (QSRR) model was validated by predictive‐ability test. The prediction results were in good agreement with the experimental values. The results demonstrated that headspace SPME‐GC‐MS and LPME‐GC‐MS are the simple, rapid and easy sample enrichment technique suitable for analysis of volatile compounds. This investigation provided an effective method for predicting the retention indices of new compounds even in the absence of the standard candidates. 相似文献
213.
The molecular and metal profile fingerprints were obtained from a complex substance, Atractylis chinensis DC—a traditional Chinese medicine (TCM), with the use of the high performance liquid chromatography (HPLC) and inductively coupled plasma atomic emission spectroscopy (ICP-AES) techniques. This substance was used in this work as an example of a complex biological material, which has found application as a TCM. Such TCM samples are traditionally processed by the Bran, Cut, Fried and Swill methods, and were collected from five provinces in China. The data matrices obtained from the two types of analysis produced two principal component biplots, which showed that the HPLC fingerprint data were discriminated on the basis of the methods for processing the raw TCM, while the metal analysis grouped according to the geographical origin. When the two data matrices were combined into a one two-way matrix, the resulting biplot showed a clear separation on the basis of the HPLC fingerprints. Importantly, within each different grouping the objects separated according to their geographical origin, and they ranked approximately in the same order in each group. This result suggested that by using such an approach, it is possible to derive improved characterisation of the complex TCM materials on the basis of the two kinds of analytical data.
In addition, two supervised pattern recognition methods, K-nearest neighbors (KNNs) method, and linear discriminant analysis (LDA), were successfully applied to the individual data matrices—thus, supporting the PCA approach. 相似文献
214.
Xiaowei Dong Hongping Huang Rong Wang Shiyu Luo Yahui Mi Yuqing Pan Wei Shen Jiamin Cui Xiaolong Hu Xuexiang Cheng Xinhong Shi Hao Wang 《Journal of separation science》2023,46(19):2300172
Chrysanthemum morifolium cv. Fubaiju is rich in phenolic compounds with various benefits such as anti-inflammatory, antioxidant, and cardiovascular protection. In this study, 12 phenolic compounds, including five flavonoid glycosides and seven quinic acid derivatives, were successfully separated from the flowers of Chrysanthemum morifolium cv. Fubaiju by high-speed counter-current chromatography and preparative high-performance liquid chromatography. Ethyl acetate-n-butanol–acetonitrile–water–acetic acid (5:0.5:2.5:5:0.25, v/v/v/v/v) was selected as solvent system to separate six fractions from the flowers of Chrysanthemum morifolium cv. Fubaiju, and 20% aqueous acetonitrile (containing 0.1% formic acid) was chosen to be the elution solvent in preparative high-performance liquid chromatography for purifying the fractions above. Luteolin-7-O-β-D-glucoside ( 1 ), luteolin-7-O-β-D-glucuronide ( 2 ), apigenin-7-O-β-D-glucoside ( 3 ), luteolin-7-O-β-D-rutinoside ( 4 ), diosmetin-7-O-β-D-glucoside ( 5 ), chlorogenic acid ( 6 ), 1,5-dicaffeoylquinic acid ( 7 ), 1,4-dicaffeoylquinic acid ( 8 ), 3,4-dicaffeoylquinic acid ( 9 ), 3,4-dicaffeoyl-epi-quinic acid ( 10 ), 3,5-dicaffeoylquinic acid ( 11 ), and 4,5-dicaffeoylquinic acid ( 12 ) were isolated with purities all above 95%, respectively. In addition, all isolates were evaluated for their protective effects on H2O2-induced oxidative damage in adult retinal pigment epithelial cells. 相似文献
215.
Lexin Shu Huixin Qiu Shumin Zhang Jing Xue Sitong Liu Jun Qian Siyue Chen Yanyan Xu Yubo Li 《Journal of separation science》2023,46(20):2300466
Schisandra chinensis is a traditional Chinese medicine, which has played an important role in the field of medicine and food. In this study, ultra-high-performance liquid chromatography quadrupole-orbitrap-mass spectrometry was used to rapidly classify and identify the chemical compositions. Note that 32, 28, and 30 kinds of compounds were successfully identified from northern Schisandra chinensis, vinegar-processed Schisandra chinensis, and wine-processed Schisandra chinensis, respectively. The cleavage patterns of various components including lignans, organic acids, flavonoids, and terpenoids were summarized, and the effects of different processing methods on Schisandra chinensis were analyzed through chemical composition. This method realized the rapid classification and identification of raw Schisandra chinensis and two different processed products, and provided references for improving the traditional processing methods, strengthening quality control, and ensuring safe clinical application. 相似文献
216.
High‐speed countercurrent chromatography isolation of flavans from Ixeris chinensis and their identification by NMR spectroscopy
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Qing‐hu Wang Bai‐yin‐mu‐qi‐er Bao Jing‐jing Han Rong‐jun Wu 《Journal of separation science》2016,39(11):2172-2178
High‐speed countercurrent chromatography, combined with macroporous resin chromatography were applied to the separation and purification of flavans from Ixeris chinensis. Four flavans, namely, 5‐methoxy‐7,4′‐dihydroxyflavan‐3‐ol ( 1 ), 5,7‐dimethoxy‐4′‐hydroxyflavan‐3‐ol ( 2 ), 5,7‐dimethoxy‐4′‐hydroxyflavan ( 3 ), and 5,7‐dimethoxy‐8‐methyl‐4′‐hydroxyflavan ( 4 ), were obtained from I. chinensis for the first time. Their chemical structural identification was carried out by spectroscopic methods, including 1D and 2D NMR spectroscopy. Amounts of 13.2 mg of compound 1 , 6.4 mg of compound 2 , 5.8 mg of compound 3 , and 14.5 mg of compound 4 were separated from 120 mg 75% ethanol fraction. The purities of 1 – 4 were 99.1, 99.2, 97.3, and 98.6 %, respectively. 相似文献
217.
Hollow‐fiber double‐solvent synergistic microextraction with high‐performance liquid chromatography for the determination of antitumor alkaloids in Coptis chinensis
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A new hollow‐fiber double‐solvent synergistic microextraction method was proposed for the extraction and concentration of trace active compounds in traditional Chinese medicine. The main variables affecting the method were investigated and optimized. Under the optimized conditions, linearities were 0.01–10 μg/mL, detection limits were lower than 0.8 ng/mL, and interday, and intraday relative standard deviations were <9.20%. Furthermore, average recoveries ranged from 102.8 to 104.1%, and enrichment factors were 6–70 for the four alkaloids tested. The antitumor alkaloid group in Coptis chinensis was screened and identified by hollow‐fiber cell fishing with high‐performance liquid chromatography. The four alkaloids were then enriched and quantified by hollow‐fiber double‐solvent synergistic microextraction with high‐performance liquid chromatography. The mechanism of the proposed microextraction method was described, and results demonstrated that the approach was a simple and reliable sample‐preparation procedure. This method, as well as hollow‐fiber cell fishing combined with high‐performance liquid chromatography can be adopted to study the different characteristic effects of the multiple components and multiple targets of traditional Chinese medicine. The approach can also be used to conduct tailored quality control of the active compounds associated with therapeutic efficacy. 相似文献
218.
Huangbai-Zhimu herb-pair (HBZMHP) is a widely used Chinese traditional medicine formula in treating various diseases; however, its active components have remained unknown. In this paper, serum chemistry and combined high-performance liquid chromatography (HPLC), diode-array detection and mass-spectrometry (MS) techniques were used to study the constituents of HBZMHP extract absorbed into rat serum after oral administration. A total of nine characteristic HPLC peaks in the TIC chromatograms were identified as magnoflorine (1), menisperine (2), palmatine (3), berberine (4), timosaponin N or timosaponin E1 (5), timosaponin D (6), timosaponin BIII, anemarsaponin C or xilingsaponin B (7) timosaponin BII (8) and timosaponin AIII (9). All of the identified peaks were constituents of HBZMHP extract. The results narrow the range of active compounds to be found in HBZMHP extract, and pave the way for the follow-up action mechanism research. 相似文献
219.
《Analytical letters》2012,45(16):2655-2664
Sample preparation technique based on an organic filter membrane (pH-resolved filter membrane microextraction) (pH-RFMME) was developed, coupled with high-performance liquid chromatography, and used to determine protoberberine alkaloids (jatrorrhizine, epiberberine, coptisine, palmatine, and berberine) in Coptis chinensis at different pH values through a one-step procedure. This green procedure provides a desirable sample pretreatment technology. The main variables affecting the extraction such as filter membrane area (or volumes of extraction solvents), sample pH, eluent pH, ionic strength, extraction stirring rate, extraction time, and sample volume were optimized. Under the optimized conditions, the enrichment factors of the analytes were 40.4–52.0, the linear ranges were 3.2–6250 ng · mL?1 for jatrorrhizine and epiberberine, 6.0–12000 ng · mL?1 for coptisine, 1.8–3600 ng · mL?1 for palmatine, and 18.8–18800 ng · mL?1 for berberine, with r 2 ≥ 0.9945. The limits of detection were less than 0.3 ng · mL?1. Satisfactory recoveries (84.8%–115.5%) and precision (1.8%–10.0%) were also achieved. These results confirmed that pH-RFMME is a simple, rapid, practical, and environmentally friendly method to isolate analytes that exhibit significant differences in acidity or alkalinity from complex samples. 相似文献
220.