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101.
飞龙掌血中三萜酸成分研究 总被引:5,自引:0,他引:5
从芸香科植物飞龙掌血中提取分离出4个新三萜酸,经波谱数据分析,分别鉴定为2α,3α,19α-trihydroxy11-oxo-urs-12-en-28-oic acid(1),2α,3α,11α,19α-tetrahydroxy-urs-12-en-28-oic acid(2),2α,3α-dillydroxy-19-oxo-18,19-seco-urs-11,13(18)-diene-28-oic acid(3)和2α,3α,19α-trihydroxy-olean-11,13(18)-dien-28-oic acid(4)。还分离鉴定出已知成分野鸭春酸(5)、arjunic acid(6)、飞龙掌血素、勒钩内脂和β-谷甾醇。 相似文献
102.
Nhiem NX Tai BH Quang TH Kiem PV Minh CV Nam NH Kim JH Im LR Lee YM Kim YH 《Bioorganic & medicinal chemistry letters》2011,21(6):1777-1781
One new ursane-type triterpenoid glycoside, asiaticoside G (1), five triterpenoids, asiaticoside (2), asiaticoside F (3), asiatic acid (4), quadranoside IV (5), and 2α,3β,6β-trihydroxyolean-12-en-28-oic acid 28-O-[α-l-rhamnopyranosyl-(1→4)-β-d-glucopyranosyl-(1→6)-β-d-glucopyranosyl] ester (6), and four flavonoids, kaempferol (7), quercetin (8), astragalin (9), and isoquercetin (10) were isolated from the leaves of Centella asiatica. Their chemical structures were elucidated by mass, 1D- and 2D-nuclear magnetic resonance (NMR) spectroscopy. The structure of new compound 1 was determined to be 2α,3β,23,30-tetrahydroxyurs-12-en-28-oic acid 28-O-[α-l-rhamnopyranosyl-(1→4)-β-d-glucopyranosyl-(1→6)-β-d-glucopyranosyl] ester. The anti-inflammatory activities of the isolated compounds were investigated on lipopolysaccharide (LPS)-stimulated RAW 264.7 cells. Asiaticoside G (1) potently inhibited the production of nitric oxide and tumor necrosis factor-α with inhibition rates of 77.3% and 69.0%, respectively, at the concentration of 100 μM. 相似文献
103.
A. V. Tsybulsky N. M. Sanina I. A. Lee A. M. Popov E. Ya. Kostetsky O. Yu. Portnyagina V. L. Shnyrov 《Biochemistry (Moscow) Supplemental Series B: Biomedical Chemistry》2007,1(4):353-358
Immunostimulating complexes (ISCOM) have been modified by replacement of structural components of ISCOM; phosphatidylcholine has been replaced, by glycolipid of monogalactosyldiacylglycerol from sea macrophytes, saponin QuilA has been replaced by triterpene glycoside, Cucumarioside A2-2. The resultant complex includes morphological structures of two types: the ISCOM-like structures with the characteristic morphology and sizes and also the tubular structures with diameter of about 40 nm and length of 150–400 nm. We have defined these structures as TI-complexes. These TI-complexes exhibit considerably lower toxicity than ISCOM. They may include an amphiphilic protein antigen and provide immunoadjuvant effect during experimental vaccination. Under conditions of the experimental immunization of mice with a weak immunogen (subunit membrane pore protein from Y. pseudotuberculosis), TI-complexes with antigen provided stronger humoral immune response to antigen than the complexes of porin with classical ISCOM, liposomes and Freund’s adjuvant. Thus, the TI-complexes represent a new type of adjuvant carriers for antigens. 相似文献
104.
Max Henry 《Phytochemistry Reviews》2005,4(2-3):89-94
The chemical structure of triterpenoid saponins is quite complicated, especially the glucuronide oleanane-type triterpene
carboxylic acid 3,28-bidesmosides (GOTCAB) saponins. Moreover, triterpenoid saponins are numerous as a result of this complicated
structure. This review tries to explain this diversity in terms of plant classification and phylogeny. The study focuses on
the three main successive steps of the biosynthetic pathway of the triterpenoid saponins: cyclisation, oxidation and glycosylation
showing the relationship between triterpenols and sterols in terms of cell membrane evolution and the importance of which
metabolic intermediates involved as aglycones of the triterpenoid saponins, represented progressively less and less in the
advanced groups of the plant kingdom as they are more and more oxidised. This oxidation seems to reflect a better adaptation
to new environmental conditions of some of these groups. By their enormous chemical diversity, the triterpenoid saponins seem
to be good candidates to study the phylogeny of the flowering plants. A first attempt is given using recent advances in botanical
classification for the orders and families by the Angiosperm Phylogenic Group (APG). This study was simplified in the first
step focusing only on the “gypsogenin group” of the GOTCAB saponins. For example, as a result, these compounds are mainly
concentrated in advanced groups such as Caryophyllideae, primitive Rosideae and Asterideae. 相似文献
105.
Two New Saponins from Lysimachia capillipes Hemsl. 总被引:1,自引:0,他引:1
Jing-Kui TIAN Zhong-Mei ZOU Li-Zhen XU Shi-Lin YANG 《植物学报(英文版)》2005,47(10):1271-1275
To investigate the saponins from whole plants of Lysimachia capillipes Hemsl., two new saponins, named capilliposide E (1) and capilliposide F (2), were isolated. The structures of the new sa ponins were elucidated as 3 β, 22α-dihydroxy- 16α-acetat-28→ 13 -lactone-oleanane-3 -O- [β-D-glucopyranosyl(1→2)-α-L-arabinpyranoyl]-22-O-β-D-glucopyranoside (1) and 3 β, 22α-dihydroxy- 16α-acetat-28→ 13-1actone-oleanane-3-O- { [β-D-glucopyranosyl-(1→2)-β-D-glucopyranosyl-(1→4)]-α-L-arabinpyranoyl }-22-O-βD-glucopyranoside (2). The structures of these compounds were determined by 1D- and 2D-NMR, MS techniques, and chemical methods. 相似文献
106.
The distribution of deuterium in squalene and β-amyrin, biosynthesized from mevalonic acid-6,6,6-d3 in Pisum sativum, has been examined b 相似文献
107.
108.
Zhang P Xu L Qian K Liu J Zhang L Lee KH Sun H 《Bioorganic & medicinal chemistry letters》2011,21(1):338-341
Epiceanothic acid (1) is a naturally occurring, but very rare pentacyclic triterpene with a unique pentacyclic triterpene (PT) structure. An efficient synthesis of 1 starting from betulin (3) has been accomplished in 12-steps with a total yield of 10% in our study. Compound 1 and selected synthetic intermediates were further evaluated as anti-HIV-1 agents, inhibitors of glycogen phosphorylase (GP), and cytotoxic agents. Compound 1 exhibited moderate HIV-1 inhibition. Most importantly, compound 5, with an opened A-ring, showed significant GP inhibitory activity with an IC50 of 0.21 μM, suggesting a potential for development as an anti-diabetic agent. On the other hand, compound 12, with a closed A-ring, showed potent cytotoxicity against A549 and MCF-7 human tumor cell lines, with IC50 values of 0.89 and 0.33 μM, respectively. These results suggest that the A-ring of PTs is an important pharmacophore that could be modified to involve different biological activities. 相似文献
109.
利用各种色谱技术从马缨杜鹃(Rhododendron delavayi Franch.)茎中分离得到10个化合物。通过波谱学方法鉴定为异鼠李素(1),nectandrin B(2),resveratrol-3-O-β-D-glucoside(3),lysidiside N(4),19α-hydroxyasiatic acid(5),白桦脂酸(6),3β-hydroxylup-12-en-28-oic-acid(7),obtusalin(8),methyl 2,4-dihydroxy-6-methylbenzoate(9),2,5-dihydroxy-3-methoxytoluene(10)。化合物2~9为首次从该种植物中分离得到。 相似文献
110.