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61.
BACKGROUND AND PURPOSE
Pharmacological activation of cannabinoid CB1 and CB2 receptors is a therapeutic strategy to treat chronic and inflammatory pain. It was recently reported that a mixture of natural triterpenes α- and β-amyrin bound selectively to CB1 receptors with a subnanomolar Ki value (133 pM). Orally administered α/β-amyrin inhibited inflammatory and persistent neuropathic pain in mice through both CB1 and CB2 receptors. Here, we investigated effects of amyrins on the major components of the endocannabinoid system.EXPERIMENTAL APPROACH
We measured CB receptor binding interactions of α- and β-amyrin in validated binding assays using hCB1 and hCB2 transfected CHO-K1 cells. Effects on endocannabinoid transport in U937 cells and breakdown using homogenates of BV2 cells and pig brain, as well as purified enzymes, were also studied.KEY RESULTS
There was no binding of either α- or β-amyrin to hCB receptors in our assays (Ki > 10 µM). The triterpene β-amyrin potently inhibited 2-arachidonoyl glycerol (2-AG) hydrolysis in pig brain homogenates, but not that of anandamide. Although β-amyrin only weakly inhibited purified human monoacylglycerol lipase (MAGL), it also inhibited α,β-hydrolases and more potently inhibited 2-AG breakdown than α-amyrin and the MAGL inhibitor pristimerin in BV2 cell and pig brain homogenates.CONCLUSIONS AND IMPLICATIONS
We propose that β-amyrin exerts its analgesic and anti-inflammatory pharmacological effects via indirect cannabimimetic mechanisms by inhibiting the degradation of the endocannabinoid 2-AG without interacting directly with CB receptors. Triterpenoids appear to offer a very broad and largely unexplored scaffold for inhibitors of the enzymic degradation of 2-AG.LINKED ARTICLES
This article is part of a themed section on Cannabinoids. To view the other articles in this section visit http://dx.doi.org/10.1111/bph.2012.167.issue-8 相似文献62.
63.
滇桑茎皮中化学成分的研究 总被引:3,自引:1,他引:2
目的研究滇桑茎皮中的化学成分。方法应用色谱技术分离纯化,通过理化性质和波谱学方法鉴定化合物的结构。结果从滇桑茎皮95%乙醇提取物中分离得到11个化合物,分别鉴定为桑树苷C(mulberroside C,1)、oxyresveratrol(2)、2′,4′,7-trihydroxy-(2S)-flavone(3)、norartocarpetin(4)、moracin P(5)、betulinic acid(6)、sitosteryl3β-glucoside6′-O-pal mitate(7)、lupeol(8)、正丁酸(9)、β-daucosterol(10)、β-sitosterol(11)。结论化合物1~11均为首次从该植物中分离得到;抗肿瘤筛选结果表明,化合物9显示出一定的抗肿瘤活性。 相似文献
64.
The species Rhus chinensis Mill. (Anacardiaceae) is an important representative of the genus Rhus, which contains over 250 individual species found in temperate and tropical regions worldwide. Rhus chinensis has long been used by folk medicine practitioners in Asia. Leaves, roots, stem, bark, fruit and particularly the galls on Rhus chinensis leaves, Galla chinensis, are recognized to have preventative and therapeutic effects on different ailments (such as diarrhea, dysentery, rectal and intestinal cancer, diabetes mellitus, sepsis, oral diseases and inflammation). However, it is critical to separate evidence from anecdote. Fortunately, recent scientific research has revealed that Rhus chinensis compounds possess strong antiviral, antibacterial, anticancer, hepatoprotective, antidiarrheal and antioxidant activities. Moreover, compounds isolated from the stem of Rhus chinensis significantly suppressed HIV‐1 activity in vitro. Compounds from this plant were also found to inhibit enamel demineralization in vitro and enhance remineralization of dental enamel with fluoride. This review highlights claims from traditional and tribal medicinal lore and makes a contemporary summary of phytochemical, biological and pharmacological findings on this plant material. It aims to show that the pharmaceutical potential of this plant deserves closer attention. Copyright © 2010 John Wiley & Sons, Ltd. 相似文献
65.
66.
目的研究大戟脂(多脂大戟Euphorbia resinifera的树脂状分泌物)的化学成分。方法采用反相C18、硅胶、凝胶柱色谱、制备型HPLC等方法进行分离纯化,通过红外、紫外、高分辨质谱、一维和二维的核磁数据和结合参考文献鉴定化合物的结构。结果从大戟脂甲醇提取物中分离得到了2个化合物,分别鉴定为大戟烷-8-烯-3,25-二醇-24-氯-7-酮(1)和22,23,24,25,26,27-六降大戟烷-8-烯-20-醇-3,7-二酮(2)。结论化合物1为新的三萜,化合物2为新的降三萜,分别命名为大戟脂A和大戟脂B。 相似文献
67.
山豆根Sophorae Tonkinensis Radix et Rhizoma用药历史悠久,为临床常用药,具有清热解毒、消肿利咽的功效。目前已从山豆根中鉴定出200多种化合物,主要含黄酮类、生物碱类、三萜类等,其中生物碱为山豆根主要活性成分。山豆根作用广泛,对免疫系统、消化系统、循环系统等均有调节作用,具有抗肿瘤、抗炎、护肝、降压、提高免疫、解痉止泻、升血糖等诸多药理作用。综述了山豆根的化学成分和主要药理作用,为山豆根的深入研究提供参考。 相似文献
68.
目的 对仿刺参(Apostichopus japonicus)体内皂苷类成分进行分离及结构鉴定,研究纯化皂苷的抗肿瘤细胞毒活性。方法 以鲜仿刺参为原材料,选用60%的乙醇溶液从海参中提取出海参皂苷,然后通过有机溶剂萃取法、大孔树脂法、硅胶柱层析、凝胶柱层析、半制备HPLC分离纯化海参皂苷,采用LTQ Orbitrap XL 质谱、Jeol JNM-ECP 600 核磁技术对得到的海参皂苷进行结构鉴定,以人肺癌细胞(A549)、人结肠癌细胞(HCT116)、人肝癌细胞(BEL-7402)、人肺腺癌细胞(NCI-H1975)和正常肝细胞(L-02)为对象对纯化皂苷抗肿瘤细胞毒活性进行研究。结果 从鲜仿刺参同时得到三种三萜皂苷类化合物,分别为Holotoxin D、Holotoxin B1和Holotoxin A1,产率分别为2.30×10-7、1.86×10-6和3.49×10-6。三种皂苷的细胞毒活性具有一致性,对肿瘤细胞具有良好的抑制率,抑制率均随皂苷单体浓度增大而增大,且到达一定浓度时之后趋于稳定,均呈现弱效抑制作用。结论 首次从鲜仿刺参中同时纯化得到Holotoxin D,Holotoxin B1和Holotoxin A1,比例为1:7.97:14.94。三种皂苷单体具有良好的抗肿瘤活性,Holotoxin D抗肿瘤活性为首次报道,本研究为以后的肿瘤药物的筛选研究奠定了良好的基础。 相似文献
69.
Lin Shi De-Hong Tan Ting-Cai Yan Dong-Hua Jiang 《Journal of Asian natural products research》2018,20(2):182-187
One new dammarane-type triterpene, gypsapogenin A (1), was isolated from the acid hydrolyzate of total saponins from Gynostemma pentaphyllum (Thunb.) Makino, together with two known compounds, (20S,24S)-3β,20,21β,23β,25-pentahydroxy-21,24-cyclodammarane (2) and (23S)-3β-hydroxydammar-20,24-dien-21-oic acid 21,23-lactone (3). Its structural elucidations were accomplished mainly on the basis of the interpretation of spectroscopic data, such as IR, HR-TOF-MS, and NMR. The cytotoxic activities were evaluated against HepG2 and A549 human cancer cell lines. 相似文献
70.
Eckart-Roderich Sailer Rainer F. Hoernlein Lakshminarayanapuram R. Subramanian Hermann P. T. Ammon 《Archiv der Pharmazie》1996,329(1):54-56
AKBA (acetyl-11-keto-β-boswellic acid, 1 ) and KBA (11-keto-β-BA, 2 ) from Boswellia serrata Roxb. and Boswellia carterii Birdw. are direct, nonredox-type inhibitors of 5-lipoxygenase, the key enzyme for leukotriene biosynthesis (IC50 = 1.5 and 3μM in intact neutrophils, respectively). In order to study the impact of the carboxyl function for enzyme inhibition, we synthesized novel analogues of boswellic acids. The C-4 alcohol derivative of KBA ( 4 ) still exerted 5-lipoxygenase inhibitory activity (IC50 = 4.5 μM), whereas ( 8 ), the C-4 alcohol analogue of β-boswellic acid ( 7 ), the methyl ester analogue of KBA ( 5 ), and acetyl-11-keto-amyrin ( 9 ) possessed no inhibitory potential in concentrations up to 50 μM. These findings reveal that a hydrophilic group at C4 in combination with an 11-keto-function is essential for 5-lipoxygenase inhibition by boswellic acids. 相似文献