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101.
Higenamine (HG) is a natural benzylisoquinoline alkaloid isolated from Aconitum with positive inotropic and chronotropic effects. This study aimed to investigate the possible cardioprotective effects of HG combined with [6]-gingerol (HG/[6]-GR) against DOX-induced chronic heart failure (CHF) by comprehensive approaches. DOX-induced cardiotoxicity model in rats and H9c2 cells was established. Therapeutic effects of HG/[6]-GR on haemodynamics, serum indices and histopathology of cardiac tissue were analysed. Cell mitochondrial energy phenotype and cell mitochondrial fuel flex were measured by a Seahorse XFp analyser. Moreover, UHPLC-Q-TOF/MS was performed to explore the potential metabolites affecting the therapeutic effects and pathological process of CHF. To further investigate the potential mechanism of HG/[6]-GR, mRNA and protein expression levels of RAAS and LKB1/AMPK/Sirt1-related pathways were detected. The present data demonstrated that the therapeutic effects of HG/[6]-GR combination on CHF were presented in ameliorating heart function, down-regulation serum indices and alleviating histological damage of heart tissue. Besides, HG/[6]-GR has an effect on increasing cell viability of H9c2 cells, ameliorating DOX-induced mitochondrial dysfunction and elevating mitochondrial OCR and ECAR value. Metabolomics analyses showed that the therapeutic effect of HG/[6]-GR combination is mainly associated with the regulation of fatty acid metabolites and energy metabolism pathways. Furthermore, HG/[6]-GR has an effect on down-regulating RAAS pathway-related molecules and up-regulating LKB1/AMPKα/Sirt1-related pathway. The present work demonstrates that HG/[6]-GR prevented DOX-induced cardiotoxicity via the cardiotonic effect and promoting myocardial energy metabolism through the LKB1/AMPKα/Sirt1 signalling pathway, which promotes mitochondrial energy metabolism and protects against CHF.  相似文献   
102.
103.
采用ISSR和RAPD分子标记技术对28个赤芍种群进行遗传变异和亲缘关系分析,为准确地评价赤芍种质的遗传特征、资源保护及新品种选育提供理论依据。结果显示:(1)利用分别筛选的14条ISSR和RAPD引物扩增出257条和215条条带,其中多态性条带分别为251条和209条,多态性条带百分率分别为97.8%和97.2%;同时证实野生赤芍种群的遗传多样性高于栽培种群。(2)根据Shannon’s信息指数(I)和Nei’s基因多样性指数(H_e)值,发现内蒙古多伦种群(DL)的遗传多样性水平最高,建议在此地建立野生赤芍资源保护区。(3)根据遗传分化系数(G_(st)),发现野生赤芍种群的遗传分化主要发生在种群内,可能由遗传漂变引起;而栽培赤芍种群的遗传分化主要在种群间,说明栽培赤芍种群间的基因交流较少。(4)两种分子标记的聚类分析结果均将28个赤芍种群聚为5大类,遗传距离变化范围分别为0.115 1~0.343 8和0.095 5~0.286 2。研究表明,互相印证的ISSR和RAPD方法可以在DNA水平上更准确有效地分析赤芍种质资源的遗传结构和遗传多样性。  相似文献   
104.
Free amino acids in the milk of cow were investigated in comparison with those in the plasma. The concentrations of most free amino acids in the milk except for a few amino acid were lower than those in the plasma. It appears that the percentage of each amino acid in the milk against the corresponding amino acid in the plasma is the reflexion of casein synthesis in the mammary gland. Nutritional alteration influenced on the level of some amino acids in the milk. Free phosphorylserine, glycerylphosphorylethanolamine, and phosphorylethanolamine were observed in the milk. Phosphorylethanolamine was present in significantly high concentration in one animal as control, whereas was almost absent in another animal as experimental.  相似文献   
105.
熟地多糖活性炭脱色工艺的研究   总被引:1,自引:0,他引:1  
本研究旨在探讨活性炭对熟地多糖提取液脱色的工艺条件。在单因素试验基础上,采用正交试验,以多糖脱色率(%)和多糖剩余率(%)为指标,用紫外-可见分光光度法测定,确定了熟地多糖活性炭脱色的最优工艺的参数。结果发现:活性炭添加量对脱色效果的影响最大,其次为温度,再次为时间。最佳脱色条件为脱色温度60℃,活性碳添加量5%,吸附时间30 min,在此条件下,脱色率为98.20%,多糖剩余率为84.89%。从而表明活性炭对熟地多糖脱色工艺可行,简便,有效。  相似文献   
106.
Sanchi, also known as Radix Notoginseng, is a Chinese traditional medicine prepared from roots of the herb Panax notoginseng. Sanchi is traditionally used as a hemostatic to control internal and external bleeding but also shows diverse bioactivities that include increasing coronary blood flow and reducing myocardial oxygen consumption and blood pressure. Although research into the potential cardioprotective effects of Sanchi is ongoing in the field of traditional Chinese medicine, we sought to explore potential benefits in cardiovascular disorders associated with excess cholesterol and hyperlipidemia. We have investigated the effects of Sanchi as a dietary supplement on hyperlipidemia and oxidative stress in male Sprague-Dawley rats maintained on a high-fat diet. Diets were supplemented with Sanchi at 0.25%, 0.5% and 1% (w/w) for four weeks, while control animals received no supplement. Sanchi administration to hyperlipidemic rats resulted in a significant decline in serum levels of total cholesterol, triglycerides and low density lipoprotein-cholesterol, with an increase in serum high-density lipoprotein-cholesterol levels. Treated animals also showed reduced levels of hepatic HMG-CoA reductase. Furthermore, Sanchi improved hepatic antioxidant status as assessed by superoxide dismutase and glutathione peroxidase activities and reduced levels of lipid peroxidation. These results suggest that Sanchi consumption can improve lipid profiles, inhibit peroxidation, and increase the activity of antioxidant enzymes, and is thereby likely to reduce the risk of coronary heart disease associated with hyperlipidemia and oxidative stress.  相似文献   
107.
新疆党参的花部综合征与次级花粉呈现   总被引:2,自引:0,他引:2  
次级花粉呈现是植物提高花粉输出和接受的效率与准确性以及促进异交的一种繁殖策略.新疆党参(Codonopsis clematidea)具有典型的次级花粉呈现特性.本文采用野外观测、授粉实验与室内显微观测等方法,对该物种的花部综合征及其次级花粉呈现过程进行了详细观测,并对这些特征的适应意义进行了探讨.结果表明:新疆党参钟状下垂的蓝色花冠及黑黄色蜜腺,不仅避免了雨水冲刷雌雄蕊、稀释花蜜以及风移出花粉等不利影响,还增加了对传粉者的吸引,延长了花粉活力及柱头可授性持续时间.次级花粉呈现属于亚顶端花柱呈现者,呈现机制为沉积机制.该特性限制了单个传粉者带走的花粉量,延长了花粉呈现时间,使更多传粉者参与传粉过程,增加了雄性适合度.其雄性先熟及雌雄蕊空间位置变化,避免了雌雄功能干扰,为传粉者取食花蜜、输出花粉以及柱头接受异源花粉提供了通道和机会.其泛化传粉系统的主要传粉昆虫为林野熊蜂(Bombus silvarum)、草地熊蜂(B.paradoxus)和树长黄胡蜂(Dolichovespula sylvestris),其较长的单花花期(6 d左右),昆虫访花高峰期与花粉活力最高时期及柱头最佳授粉期相吻合,以及较大的泌蜜量、较高的花蜜糖浓度和较长的泌蜜时间等特征,可提高传粉者的访花频率,增加成功传粉的机会和传粉效率.在气候多变的天山山区,该物种特殊的花部综合征和次级花粉呈现机制对提高其传粉效率并促进异交繁殖成功具有重要意义.  相似文献   
108.
Rehmanniae Radix Praeparata is the processed products of the root of Rehmannia glutinosa. It has been used as a Traditional Chinese Medicine for thousands of years, and it has been found to possess widely pharmacological activities. In this study, three new 2,2′-difurylketone derivatives (rehmanniaeketone A–C) and two new chromones [3,8-dihydroxy-2-(2-hydroxyethyl)chromone and 3,8-dihydroxy-2-[(2-O-α-D-galactopyranosyloxy)ethyl]chromone] were isolated from the Rehmanniae Radix Praeparata. Furthermore all of the compounds were subjected to cytotoxic testing against the human lung carcinoma A549 cells. The cytotoxic results showed that rehmanniaeketone B and rehmanniaeketone C exhibited more stronger inhibition effects on the cell activity of A549 cells with the IC50 5.23 μM and 2.05 μM than other compounds. And 3,8-dihydroxy-2-(2-hydroxyethyl)chromone exhibited moderately inhibitory activity with the IC50 61 μM. Rehmanniaeketone A and 3,8-dihydroxy-2-[(2-O-α-D-galactopyranosyloxy]chromone showed no inhibitory effects.  相似文献   
109.
甘肃岷县当归不同药用部位挥发油的提取及其成分分析   总被引:1,自引:0,他引:1  
采用水蒸气蒸馏法分别提取产于甘肃岷县道地产区当归的当归身、当归尾、当归头中的挥发油,使用气相-质谱联用(GC-MS)分析其挥发油的化学组分.在相同提取测定条件下,当归不同部位提取的挥发油中各化学成分含量存在差异性,当归身、当归尾、当归头在保持较多藁本内酯的同时,均含有其他有效成分,且这些有效成分种类与含量不尽相同.提示当归不同药用部位的挥发油化学成分含量具有一定的差异,药理作用的物质基础不同,探寻当归不同部位的挥发油的化学成分变化规律,为中药当归的加工及临床应用提供科学依据.  相似文献   
110.
独活活性单体对中型指环虫的杀灭作用及其成分鉴定   总被引:2,自引:0,他引:2  
利用硅胶柱层析和生物活性跟踪对独活乙醇提取物进行杀中型指环虫活性成分的分离纯化, 并测定活性成分在不同浓度条件下的离体生物活性, 通过薄层色谱(TLC)、紫外光谱(UV)、高效液相色谱(HPLC)、气质联用(GC-MS)对活性成分进行鉴定。结果表明: 从独活分离得到的F 和K1-2-3 两种流分均对中型指环虫具有不同程度的杀灭作用, 其中F 流分48h 内的完全杀灭中型指环虫的浓度为1.6 mg/L, 而K1-2-3 的使用浓度分别为5 mg/L 时, 其48h 内对中型指环虫的杀灭率为74.9%。经理化性质测定和光谱分析, F 流分和K1-2-3流分分别鉴定为蛇床子素和东莨菪内酯。    相似文献   
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