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1.
Microbeads and fragments have been widely studied, while glitter remains neglected by the literature although found in a variety product (e.g., body paints, nail polish, cosmetics, craft products). The main aim of this study was to assess the effects of different types and concentrations of glitter particles on Mytilus galloprovincialis after 7 days of exposure. The experiment was divided into a preliminary test and a confirmatory test. Our findings support the hypothesis for a link between concentration and type of glitter particles, percentage of recovery and oxidative stress in M. galloprovincialis. There was a significant correlation between particle length and percentage of particles recovered in water, suggesting that the digestive tract of M. galloprovincialis retains smaller particles more. In addition, we noted an increase in antioxidant defense induced by smaller particles. Moreover, certain types of glitter crumbled and shortened in length, resulting in higher levels of oxidative stress biomarkers. Finally, the star-shaped glitter particles had a different effect on oxidative stress biomarkers. Further studies are needed to clarify the toxic effects of glitter on aquatic organisms and to quantify its proportion to other microplastics in the environment.  相似文献   
2.
目的 通过对含海马方剂构成信息进行数据挖掘和知识发现,构建关联网络,分析海马的历代应用情况,挖掘海马用药配伍经验,发现海马潜在功效和主治病症,为海马的临床应用和开发提供依据。方法 以《中医方剂大辞典》《中国药典》《中华医典》等多部著作为方源,收集含有海马的相关方剂,并进行频数分析、关联规则挖掘和关联网络的构建。结果 共筛选有文献记载的含海马方剂154首。从剂型看,大多为散剂,从方剂分布年代来看,海马的应用虽然有很长历史,但是古代应用并不广泛,现代应用较多。通过对配伍药物进行分析发现,与海马配伍频率较高的是“鹿茸”、“熟地黄”、“肉苁蓉”等补益药物。从功效主治方面看,大多数方剂具有“补肾”、“温阳”、“益精”等传统功效外,还具有健脑等功效;主治病症中,除“阳痿”、“癥瘕”、“疔疮”等《中国药典》所记载的疾病之外,还可治疗“虚劳”、“健忘”、“瘿病”、“不寐”、“痹证”、“小便淋沥或不通”等。对其进行关联关系分析发现,海马配伍补肾温阳的效果较为明显,多用于治疗阳痿,且腰痛、虚劳、遗精、健忘、不育等疾病的治疗与补肾关系密切;在治疗癥瘕时,多与醋、樗鸡、干漆、硇砂、斑蝥、水蛭、没药、当归配伍。结论 该研究不仅发现了含海马方剂的常用剂型、分布年代和药物配伍规律,发现了历代医家应用海马的临床经验,还探索了海马的潜在应用价值。海马作为一味海洋中药,具有温、补、托、消等特性,除常用于治疗阳痿外,还可用于治疗腰痛、健忘、瘿病、不寐、痹证等病症,这些研究结果可为拓展海马的临床应用提供理论基础及依据。  相似文献   
3.
Pharmaceutical drugs in the wild may pose significant risks to non-target exposed organisms. This situation is even more troublesome for coastal marine or estuarine environments, located in the vicinity of large human conglomerates, for which the putative number of pollutants is extremely high, and the regime by which wild organisms are exposed is continuous. In addition, the number of studies addressing this issue is still scarce, despite evidences that show the potential contamination profiles and adverse biological effects in organisms from such areas. In this study, the ecotoxicity of common pharmaceutical drugs (namely paracetamol and acetylsalicylic acid) was assessed, by studying the susceptibility of the mussel species Mytilus spp to oxidative stress after being exposed for 96 h to increasing but ecologically relevant concentrations of the two mentioned pharmaceuticals (paracetamol: 0, 0.5, 5, 50, and 500 μg/L; acetylsalicylic acid: 0, 0.1, 1, 10, and 100 μg/L). The oxidative status in exposed organisms was analyzed by measuring oxidative stress biomarkers, namely catalase (CAT), glutathione-S-transferases (GSTs), and lipoperoxidation (LPO) levels, whose alteration was indicative of chemical exposure, in both digestive gland and gills of the organisms. In addition, the food uptake and the nutritional reserve status of exposed organisms were also assessed, by measuring the consumption of ingested food, and levels of tissue reserves of glycogen in gills and digestive gland. No significant alterations were observed in the assessed oxidative stress parameters so it was possible to hypothesize that the studied drugs may have probably exerted a limited alteration of antioxidant defenses and damage, which was reverted by the activation of defensive adaptive mechanisms. This set of data evidenced that the pro-oxidative metabolism that was already described for both drugs in other animal models, was not fully established in the exposed mussels. On the contrary, glycogen reserves were substantially changed after exposure to both toxicants, being possible to observe opposite responses caused by both drugs. Food uptake was not altered following exposure to the drugs. Further evaluations are thus required to conclude about both drugs ecotoxicity and other parameters, namely seasonality, which should be considered when performing ecotoxicology tests, especially with the selected species.  相似文献   
4.
目的 对抗凝血活性海洋硫酸多糖HP1-1的结构进行研究。方法 通过高效液相色谱(HPLC)、高效凝胶渗透色谱(HPGPC)、傅里叶变换红外光谱(IR)以及气质联用色谱(GC-MS)和核磁共振波谱(NMR)方法,对抗凝血活性海洋硫酸多糖HP1-1的结构进行解析。结果 海洋硫酸多糖HP1-1的分子量为297 kDa,总糖和硫酸基含量分别为78.1%和12.3%;HP1-1主要由葡萄糖组成,含有少量半乳糖、阿拉伯糖和甘露糖;HP1-1糖链中含有→4)-Glcp-(1→、→3)-Glcp-(1→、→3,4)-Glcp-(1→、→4)-Arap-(1→、→3,4)-Galp-(1→和→3)-Galp-(1→,硫酸基位于→4)-Glcp-(1→的C-3位和→3)-Galp-(1→的C-4位。 结论 海洋多糖HP1-1是主要由葡萄糖组成的硫酸多糖,含有多种糖基连接方式,为独特结构序列的新颖海洋硫酸甘露阿拉伯半乳葡聚糖。  相似文献   
5.
老鼠簕是一种重要的具海洋药用价值的红树林植物。以分光光度法(齐墩果酸为对照品,5%香草醛-冰醋酸和高氯酸为显色剂)测定红树植物老鼠簕中总三萜的含量。实验结果表明:在500nm波长条件下,齐墩果酸在0.04~0.20mg·mL-1范围内,0~60min间,吸光度与含量线性关系良好;首次测定得到,红树植物老鼠簕根的总三萜含量为0.62%,(RSD=0.91%,n=3);茎的总三萜含量为2.20%(RSD=3.94%,n=3);叶的总三萜含量为1.59%(RSD=5.04%,n=3)。  相似文献   
6.
7.
采用平板涂布法利用3种培养基从青岛即墨市田横镇泊子盐场盐池底泥样中共分离纯化出15株放线菌,对分离菌株进行16S rRNA基因测序分析。发现这15株放线菌分属于链霉菌属(Streptomyces)、拟诺卡氏菌属(Nocardiopsis)和1个新属,其中Streptomyces属为优势菌属;菌株CXB832与Nocardiopsis arabia DSM 45083THaloactinospora albus DSM 45015T最接近,同源性分别为95.4%和94.9%,根据其表型和分子特征可以初步判定该菌株为放线菌新属。培养基及培养温度对盐池环境中放线菌的分离效果均有影响,利用淀粉酪素培养基在37℃分离的放线菌种类和数量较多。在15株放线菌中,分别有12株、3株、2株和1株放线菌产淀粉酶、酯酶、蛋白酶和纤维素酶。  相似文献   
8.
目的:研究新型海洋双吲哚纤溶活性化合物FGFC1对血小板聚集的影响,发现纤溶活性化合物FGFC1与血小板相关因子变化的关系,同时比较双吲哚化合物FGFC1和单吲哚化合物FGFC2作用于血小板的异同。方法:从新鲜兔血收集血小板,调整反应体系血小板密度,以乙酰水杨酸为阳性对照,采用微量比浊法分析FGFC1和FGFC2对血小板聚集率的影响,用酶联免疫法测定FGFC1和FGFC2对血小板生理因子含量的变化。结果:FGFC1对ADP和AA诱导的血小板聚集具有抑制作用,最大抑制率分别达到42.58%±1.7%和47.82%±2.18%;FGFC2对ADP、AA和胶原诱导的血小板聚集均具有抑制作用,最大抑制率分别为50.12%±1.02%、45.28%±1.09%和50.28%±2.12%。FGFC1与FGFC2均能提升血小板内环磷酸腺苷含量,且FGFC2能明显降低血小板内血栓素A2含量。结论:海洋双吲哚纤溶活性化合物显著抑制血小板聚集,FGFC1通过影响血小板环磷酸腺苷的含量实现抑制血小板聚集,FGFC2可能通过不止一种途径抑制血小板聚集。吲哚化合物抑制血小板聚集与分子结构密切相关。  相似文献   
9.
Marine natural products have as of now been acknowledged as the most important source of bioactive substances and drug leads. Marine flora and fauna, such as algae, bacteria, sponges, fungi, seaweeds, corals, diatoms, ascidian etc. are important resources from oceans, accounting for more than 90% of the total oceanic biomass. They are taxonomically different with huge productive and are pharmacologically active novel chemical signatures and bid a tremendous opportunity for discovery of new anti-cancer molecules. The water bodies a rich source of potent molecules which improve existence suitability and serve as chemical shield against microbes and little or huge creatures. These molecules have exhibited a range of biological properties antioxidant, antibacterial, antitumour etc. In spite of huge resources enriched with exciting chemicals, the marine floras and faunas are largely unexplored for their anticancer properties. In recent past, numerous marine anticancer compounds have been isolated, characterized, identified and are under trials for human use. In this write up we have tried to compile about marine-derived compounds anticancer biological activities of diverse flora and fauna and their underlying mechanisms and the generous raise in these compounds examined for malignant growth treatment in the course of the most recent quite a long while.  相似文献   
10.
Plasma gonadotropin (GtH) levels and state of oocyte development were determined in adult female coho salmon following single intraperitoneal injections of LH-RH or its superactive analog des-Gly10[D-Ala6]LH-RH-ethylamide (LH-RHA DAla6). The peptides injected at dosages of 1.0 or 0.2 mg LH-RH and 0.2 or 0.02 mg LH-RHA DAla6/kg bw elevated plasma GtH by 1.5 hr postinjection. The response to the analog was of longer duration. Plasma GtH levels returned to basal levels 24 hr following LH-RH injection while elevated plasma GtH levels were maintained for at least 96 hr in response to the analog. Only those fish injected with LH-RHA DAla6 showed an accelerated rate of germinal vesicle breakdown (GVBD). Based on their relative effects on GVBD, LH-RHA DAla6 has at least 50 times the biological potency of LH-RH in adult female coho salmon.  相似文献   
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