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951.
目的 监测分析l0种抗真菌药物的耐药现状,以加强抗真菌药物的合理应用。方法 对我院2001年4月~2002年12月分离鉴定出的359株真菌.用目前常用的l0种抗真菌药物进行药物敏感试验和分析。结果 在l0种抗真菌药物中,耐药率最高的是灰黄霉素(耐药率87.3%~100%),其次为氟康唑(42.8%-54.9%)和伊曲康唑(28.5%~50.9%)。结论 当前临床常用抗真菌药物的耐药菌株明显增多,特别是氟康唑、伊曲康唑耐药率增高,敏感率降低,应引起广大临床医生的高度重视。  相似文献   
952.
The aim of the present study was to investigate the influence of the size and the porosity of excipient microcrystalline cellulose (MCC) particles on the densification and the deformation during compaction and the consequent effect on the drug release from reservoir pellets. Drug pellets consisting of salicylic acid and microcrystalline cellulose were prepared by extrusion-spheronisation and spray-coated with ethyl cellulose (ethanol solution). Excipient pellets of different size and porosity were prepared by extrusion-spheronisation or direct spheronisation. Five binary mixtures of reservoir pellets and excipient particles were prepared in the proportion 1:7 and lubricated. After compaction the reservoir pellets were retrieved and analysed to determine the intragranular porosity, surface area, shape and drug release. The reservoir pellets were shown to undergo extensive deformation and densification during compaction, resulting in a preserved or even prolonged drug release time. The mode of deformation of the reservoir pellets seems to be critical for the compression-induced change in drug release. Formation of large indents has a negative effect on the release time, while the use of small particles or small deformable agglomerates has a protective effect. We also hypothesize that the coating structure changes during compaction and the final structure of the coating is the net effect of two parallel processes, one reducing and one prolonging the drug transport time across the coating.  相似文献   
953.
In this study, reservoir pellets were prepared and their compression behaviour as well as the importance of their porosity for compression-induced changes in drug release was investigated. Pellets of three different porosities, consisting of microcrystalline cellulose and salicylic acid, were prepared by extrusion–spheronisation and spray-coated with ethyl cellulose (ethanol solution). Lubricated reservoir pellets were compressed and retrieved by deaggregation of the tablets. The retrieved pellets were analysed regarding porosity, thickness, surface area, shape and drug release. It was found that the coating did not significantly affect their compression behaviour. Compaction of pellets of high original porosity considerably affected densification and degree of deformation, whereas the effect on drug release was minor. For low porosity pellets the influence of compaction on drug release was appreciable, but only slight regarding densification and degree of deformation. In conclusion, the porosity of pellets is a potential factor that the formulator can use to optimize drug release and one that can affect the robustness of a formulation during manufacture. Moreover, the coating may be able to adapt to the densification and deformation of the pellets.  相似文献   
954.
某部队医院1999~2001年心血管药物应用分析   总被引:1,自引:0,他引:1  
目的:了解某部队医院心血管类药物应用现状和发展趋势。方法:以限定日剂量法和消耗金额排序法对1999-2001年该院心血管类药物水泵品种和金额进行归类统计,分析该类药物用药情况。结果:该类药物费用上升较快;钙拮抗药,防治心绞痛药物和降压药等应用最多;临床应用以国产和合资生产品种为主。结论:该类药物费用增加很快,应注意合理用药。  相似文献   
955.
目的 对国内6个不同厂家生产的盐酸小柒碱片及胶囊进行了体外溶出度考察。方法 按《中华人民共和国药典》2000年版^[1]溶出度测定法第2法,测定盐酸小檗碱片及胶囊的溶出度,提取参数(T50、Td、m),并对参数进行相关性研究。结果 除D厂的片剂的溶出度不符合药典规定外,其余4个厂的片剂及F厂的胶囊在45min时的溶出量均大于70%。结论 表明各厂家的产品溶出参数存在显性差异(P<0.01)。  相似文献   
956.
胚泡着床不全的实验动物模型   总被引:3,自引:1,他引:3  
目的 建立胚泡着床不全的实验动物模型及观测指标。方法 妊娠动物皮下注射米非司酮或利洛司酮 ,皮下注射吲哚美辛 (消炎痛 ) ,皮下注射催产素 ,给避孕药酒灌胃 ,宫腔注射纤连蛋白抗体或层粘蛋白抗体 ,皮下注射卵泡刺激素抗血清等。结果 上述方法处理后着床动物明显减少 ,着床位点数减少 ,着床率降低 ,卵巢组织上黄体数目减少 ,血清孕激素水平下降 ,绒毛膜促性腺激素水平降低。结论 上述方法均可选用来建立胚泡着床不全的动物模型  相似文献   
957.
丙泊酚对N-甲基-D-天冬氨酸所致PC12细胞损伤的保护作用   总被引:8,自引:0,他引:8  
目的 探讨静脉麻醉药丙泊酚 (PPF)脑保护作用的可能机制。方法 乳酸脱氢酶 (LDH)法及MTT比色法判断细胞损伤程度及细胞存活率 ,Fura 2 /AM荧光标记法测定细胞内Ca2 + 浓度 ( [Ca2 + ]i)的变化 ,分光光度法测定细胞一氧化氮合酶 (NOS)活性。结果 N 甲基 D 天冬氨酸 (NMDA) 3 0 0 μmol·L-1处理4h可明显导致PC1 2细胞的损伤 ,表现为LDH释放量明显增加 ,吸光度值A570nm明显降低 ,细胞存活率降低 ,同时 [Ca2 + ]i 和NOS活性则明显增加。PPF6.2 5 ,2 5 ,1 0 0 ,40 0 μmol·L-1与NMDA同时处理PC1 2细胞则使LDH释放量显著降低 ,细胞存活率增加。PPF 1 2 .5和 1 2 5 μmol·L-1可显著降低NMDA诱导的[Ca2 + ]i 水平及NOS活性的提高。结论 PPF对NMDA所致的PC1 2细胞损伤有明显的保护作用 ,其机制可能与其抑制NMDA受体的功能 ,降低 [Ca2 + ]i,减弱Ca2 + 超载 ,并降低NMDA诱导的NOS活性增加有关。提示PPF可能是通过抑制NMDA受体 Ca2 + NOS通路的功能而产生细胞保护效应  相似文献   
958.
目的制备阿苯达唑聚氰基丙烯酸正丁酯纳米粒(albendazole polybutycyanocrylate nanoparticles,ABZ-PBCA-NP)TDDS给药系统,并考察相关特性及组织分布靶向性。方法种子乳化聚合法制备阿苯达唑纳米粒;等温吸附法考察纳米粒载药特性;动态透析法研究4种制剂的体外释药动力学;同位素标记阿苯达唑纳米粒在小鼠脏器组织分布和生物利用度。结果ABZ-PBCA-NP体外释药遵循Higuchi方程,加入PVP制成的载药纳米粒符合双指数函数。纳米粒的载药方式遵循Langmuir吸附方程。小鼠ig 3H-ABZ-PBCA-NP后, 药物的肝、脾中的靶向指数分别为11.4和3.9,阿苯达唑纳米粒和混悬剂相对生物利用度分别为76.0%和36.9%。结论制备纳米粒加入PVP可使药物具吸附性和分散性,纳米粒载体可降低药物与血浆蛋白结合率,增强药物的肝、脾脏器靶向性和延缓释药。  相似文献   
959.
OBJECTIVETo investigate sustained release tested in vitro FMC SeaKem HGT Agarose-carbplatin mixture for the local intra-live. METHODTo establish the mode of the dissolution rate testing for the drug implanting in the local intra-liver. Improved the Flo  相似文献   
960.
Genetic Variations in Bone Density, Histomorphometry, and Strength in Mice   总被引:6,自引:0,他引:6  
The purpose of this study was to assess breed-related differences in bone histomorphometry, bone biomechanics, and serum biochemistry in three mouse breeds shown to differ in bone mineral density (BMD) (as measured by DXA) and bone mineral content (BMC). Femurs, tibiae, and sera were collected from 16-week-old C3H/HeJ {C3H}, C57BL/6J {BL6}, and DBA/2J {DBA}mice (n = 12/breed). Data collected included BMC and BMD (femora), histomorphometry of cancellous (distal femur) and cortical bone (diaphyseal tibiae and femora), bone strength (femora), and serum alkaline phosphatase (ALP). Consistent with previous reports, BMC and BMD were higher in C3H than in BL6 or DBA mice. The higher BMD in the C3H breed was associated with greater cancellous bone volume, cortical bone area, periosteal bone formation rate, biomechanical strength, and serum ALP. However, mid-diaphyseal total femoral and tibial cross-sectional area and moment of inertia were greatest in BL6, intermediate in C3H, and lowest in DBA mice. The specific distribution of cortical bone in C3H, BL6, DBA mice represents a difference in adaptive response to similar mechanical loads in these breeds. This difference in adaptive response may be intrinsic to the adaptive mechanism, or may be intrinsic to the bone tissue material properties. In either case, the bone-adaptive response to ordinary mechanical loads in the BL6 mice yields bones of lower mechanical efficiency (less stiffness per unit mass of bone tissue) and does not adapt as well as that of the C3H mice where the final product is a bone with greater resistance to bending under load. We suggest that the size, shape, and BMD of the bone are a result of breed-specific genetically regulated cellular mechanisms. Compared with the C3H mice, the lower BMD in BL6 mice is associated with long bones that are weaker because the larger cross-sectional area fails to compensate completely for their lower BMD and BMC. Received: 16 November 1999 / Accepted: 19 April 2000 / Online publication: 27 July 2000  相似文献   
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