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51.
Bioassay-guided fractionation of MeOH extract from fenugreek (Trigonella foenum-graecum L.) seeds resulted in the isolation of two rat growth-hormone release stimulators in vitro, fenugreek saponin I (1) and dioscin (9), along with two new, i.e., 2 and 3, and five known analogues, i.e., 4-8. The structures of the new steroidal saponins, fenugreek saponins I, II, and III (1-3, resp.), were determined as gitogenin 3-O-beta-D-xylopyranosyl-(1-->6)-beta-D-glucopyranoside, sarsasapogenin 3-O-beta-D-xylopyranosyl-(1-->6)-beta-D-glucopyranoside, and gitogenin 3-O-alpha-L-rhamnopyranosyl-(1-->2)-beta-D-glucopyranoside, respectively. Fenugreek saponin I (1) and dioscin (9) caused ca. 12.5- and 17.7-fold stimulation of release, respectively, of rat growth hormone from rat pituitary cells, whereas gitogenin (5) showed moderate activity. To our knowledge, this is the first study to demonstrate that steroidal saponins stimulate rat growth-hormone release in rat pituitary cells.  相似文献   
52.
H. Wang  J. Gao  J. Kou  D. Zhu  B. Yu 《Phytomedicine》2008,15(5):321-326
Bioassay-guided investigation was performed to identify the active constituents from a methanol extract of Polygala japonica, a folk medicinal plant widely used in China to treat inflammatory diseases. The n-BuOH and EtOAc fractions of the P. japonica methanol extract, which show significant anti-inflammatory activity in in vivo test, were further subjected to column chromatography to afford six triterpene glycosides, marked here as saponins 1–6. All compounds were evaluated for their anti-inflammatory activity in the carageenan-induced mouse paw edema test, and saponins 1, 4 and 5 showed significantly anti-inflammatory effects on both phases of carageenan-induced acute paw edema in mice. Saponin 5 was also found to significantly inhibit the production of inflammatory mediators – nitric oxide (NO) in LPS-stimulated RAW264.7 macrophages, with no obvious effects on macrophage viability.  相似文献   
53.
A simple and accurate method involving high-performance liquid chromatography with evaporative light scattering detection was developed for the simultaneous determination of five triterpenoid saponin components in Clematis L. spp. for the first time. The analysis was performed on a Zorbax SB-C(18) column and gradient elution with acetonitrile and water with 0.1% formic acid was utilised. All the calibration curves exhibited good linear characteristics with correlation coefficients in the range from 0.9979 to 0.9997. The limits of detection and limits of quantification were less than 0.152 and 0.506 microg, respectively. The overall recoveries for the five analytes were between 91.3 and 99.5%. A total of 10 samples from Clematis L. spp. were analysed under optimised conditions and the chemical profiles provided information for the identification of botanical origin, the development of new medicinal resources and chemotaxonomic investigation.  相似文献   
54.
胡芦巴水溶性甾体皂苷的提取分离工艺研究   总被引:2,自引:0,他引:2  
以薯蓣皂苷元的提取率为指标,应用L9(3^4)正交试验设计优化了从脱多糖、脱脂胡芦巴豆粉中提取甾体皂苷的工艺条件,并且筛选了ZTC澄清剂对胡芦巴甾体皂苷水提取液的澄清条件。实验结果表明,影响水提取的主次因素为:提取次数>提取温度>固液比>提取时间;最佳水提取条件为:固液比为1:10,在70℃下提取3次,每次120min得出胡芦巴种子水提取液的澄清条件如下:ZTCl 1澄清剂的加入次序是先加B组分再加入A组分;澄清剂B和A的最佳用量分别为1.0g/L和O.5g/L;加入组分A或B后在80℃下作用30min即可达到澄清目的。  相似文献   
55.
百合皂苷的提取、纯化及其对自由基的清除作用   总被引:9,自引:0,他引:9  
本文用正交实验法对百合总皂甙的提取工艺中温度、乙醇浓度、固液比例、回流时间和提取次数5个因素进行研究,优选出简便可靠、且适合工业化生产的百合总皂甙的提取工艺。其最佳提取工艺条件是:温度为60℃,乙醇浓度为70%,固液比例为1∶6,提取时间3h,提取次数3次。以溴邻苯三酚红(BPR)为显色剂,基于Co(II)H2O2体系反应产生的羟自由基(·OH)使溴邻苯三酚红(BPR)的颜色发生变化,采用756型紫外可见分光光度计测定其吸光度的变化值,研究百合皂苷在此体系中清除羟自由基的作用,对照实验表明:百合总皂苷提取物对羟自由基的清除作用比人参皂苷强。  相似文献   
56.
复合酶解法提取三七皂苷的实验研究   总被引:8,自引:2,他引:6  
以三七提取液中总皂苷的含量和提取物得率为指标,考察了乙醇回流法、渗漉法、纤维素酶解法、果胶酶解法、复合酶解法的优劣,并采用单因素法和四因素(纤维素酶用量、果胶酶用量、酶解温度、乙醇浓度)三水平正交设计法对复合酶解法提取工艺条件进行优选,得到如下较理想的提取工艺条件:纤维素酶用量为15U/g(生药)、果胶酶用量为140U/g(生药),酶解pH值为4.5,酶解温度为50℃,乙醇浓度为80%,提取时间为2.5h。所得三七提取液中总皂苷的含量为12.01%,提取物得率为35.82%。  相似文献   
57.
Yucca schidigera (Agavaceae) is one of the major commercial source of steroidal saponins. Two products of yucca are available on the market. These include dried and finely powdered logs (yucca powder) or mechanically pressed and thermally condensed juice (yucca extract). These products possess the GRAS label which allows their use as foaming agent in soft drink (root beer), pharmaceutical, cosmetic, food, and feeding-stuffs industries. The main application of yucca products is in animal nutrition, in particular as a feed additive to reduce ammonia and fecal odors in animal excreta. The positive effects of dietary supplementation with yucca products on the growth rates, feed efficiency, and health of livestock seem to be due not only to the saponin constituents but also to other constituents. These observations prompted us to investigate the phenolic constituents of Y. schidigera. This study led to the isolation of resveratrol, trans-3,3′,5,5′-tetrahydroxy-4′-methoxystilbene, the sprirobiflavonoid larixinol along with novel phenolic derivatives with very unusual spirostructures, named yuccaols A–E and yuccaone A. Taking into account the multifunctional activities of resveratrol and the novelty of yuccaols A–E, structurally related to resveratrol, a program aimed to evaluate for yucca phenolics some of the activities exerted by resveratrol has been carried out. This review describes the chemistry of yucca saponins and phenolics, summarizes the biological activities of yucca products and constituents and gives an account on the actual and potential applications of yucca products.  相似文献   
58.
Pseudorabies, a herpesvirus infection, is mainly controlled by using attenuated live vaccines. In this study, the effect of ginseng stem and leaf saponins (GSLS) in combination with selenium (Se; in the form of sodium selenite) on vaccination against attenuated pseudorabies virus (aPrV) was evaluated. It was found that GSLS and Se have an adjuvant effect and that a combination of GSLS and Se stimulates significantly enhanced immune responses than does GSLS or Se alone. Following oral administration of GSLS, mice immunized with an attenuated PrV vaccine diluted in Se‐containing physiological saline solution (PSS) provoked a significantly stronger gB‐specific serum antibodies response (IgG, IgG1 and IgG2a), enhanced lymphocyte proliferation and cytolytic activity of NK cells, along with higher production of cytokines (IFN‐γ, IL‐12, IL‐5 and IL‐10) by splenocytes. Notably, the combination of GSLS and Se conferred a much higher resistance to fPrV challenge after immunization of the mice with aPrV vaccine. This study offers convincing experimental evidence that an injection of Se with oral GSLS is a promising adjuvant combination that improves the efficacy of vaccination against PrV and deserves further study regarding improvement of responses to other animal vaccines.  相似文献   
59.
Roots of Gypsophila L. (Caryophyllaceae) have been shown to accumulate bidesmosides of triterpenoid carboxylic acids, also called GOTCAB saponins (Glucuronide Oleanane-type Triterpenoid Carboxylic Acid 3, 28-Bidesmosides). The study aimed at in-depth characterization of GOTCABs from root extracts of cultivated Gypsophila scorzonerifolia Ser., G. acutifolia Stev. ex Spreng., G. altissima L., G. pacifica Kom., G. paniculata L., G. oldhamiana Miq. and G. zhegualensis Krasnova using ultra high-performance liquid chromatography coupled with hybrid quadrupol-Orbitrap high resolution mass spectrometry (UHPLC-HRMS). Based on the accurate mass measurements, elemental composition, isotopic peak profiles, fragmentation pattern in tandem mass spectrometry (MS/MS) and literature data, a total of 53 GOTCABs were tentatively identified. In addition, 29 core structures, forming between 2 and 12 isobaric isomers were described. They possess gypsogenin, quillaic and gypsogenic acid as sapogenin, substituted at C-3 with O-β-d-galactopyranosyl-(1 → 2)-[pentosyl-(1 → 3)]-β-d-glucuronopyranoside (β-chain). According to the C-28 ester-bonded oligosaccharide (α-chain) saponins were classified into four groups: GOTCABs with C-28 tetra- and pentasaccharide (type I), GOTCABs with C-28 oligosaccharide substituted with methoxycinnamoyl group (type II), GOTCABs with mono- and diacetylated C-28 oligosaccharide (type III) and GOTCABs with C-28 oligosaccharide substituted with both acetyl and methoxycinamoyl groups (type IV). The possible fragmentation pathways of saponins were proposed. Eleven core structures forming between 2 and 7 isobars are undescribed in the literature. To examine the differences between the assayed Gypsophila species at the same environmental conditions, the variation of saponins was estimated by hierarchical clustering on isobaric fingerprints of GOTCABs. The clustering of the studied species revealed three well-defined clusters. The first cluster comprises G. scorzonerifolia (G1) and G. altissima (G3), characterized by GOTCABs from type III. G. acutifolia (G2) and G. pacifica (G4) formed the second cluster accumulating saponins from types II and III. The third cluster grouped G. paniculata (G5), G. oldhamiana (G6) and G. zhegualensis (G7) sharing GOTCABs from types IV in addition to II and III. This is the first report on the saponins from G. scorzonerifolia and G. zhegualensis. An in-depth depiction of the GOTCAB saponin composition of seven cultivated Gypsophila species was achieved. Therefore, saponins are worth investigating for better understanding of the potential use of Gypsophila roots for pharmaceutical purposes.  相似文献   
60.
Athenaea (Solanaceae) is an endemic genus belonging to the Brazilian Atlantic Rainforest. Recently, botanical investigations suggested the re‐evaluation of the generic status of the genus Athenaea as a synonym of Aureliana. In this study, the first investigation of the Athenaea genus performed on Athenaea martiana by means of HPLC‐HR‐MS‐SPE‐NMR combined with high‐resolution radical scavenging profile led to identification of several phenolic acids as radical scavengers: protocatechuic acid ( 1 ), 4‐hydroxybenzoic acid ( 2 ), caffeic acid ( 3 ), vanillic acid ( 4 ), and ferulic acid ( 6 ). Additional analysis revealed a new steroidal lactone, named athenolide A ( 9 ). Their structures were elucidated by extensive use of NMR spectroscopy as well as HR‐MS. Chemotaxonomic considerations based on these results supported the chemical relationships between the Athenaea and Aureliana genera, in agreement with the recent botanical findings.  相似文献   
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