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101.
The role of helminth treatment in autoimmune diseases is growing constantly. Systemic lupus erythematosus (SLE) is a multi‐system autoimmune disease with challenging treatment options. Tuftsin–phosphorylcholine (TPC) is a novel helminth‐based compound that modulates the host immune network. This study was conducted to evaluate the potential value of TPC in ameliorating lupus nephritis in a murine model and specifically to compare the efficacy of TPC to the existing first‐line therapy for SLE: corticosteroids (methylprednisolone). Lupus‐prone NZBxW/F1mice were treated with TPC (5 µg/mouse), methylprednisolone (MP; 5 mg/body weight) or phosphate‐buffered saline (PBS) (control) three times per week once glomerulonephritis, defined as proteinuria of grade > 100 mg/dl, was established. Levels of anti‐dsDNA autoantibodies were evaluated by enzyme‐linked immunosorbent assay (ELISA), splenic cytokines were measured in vitro and the kidney microscopy was analysed following staining. TPC and MP treatments improved lupus nephritis significantly and prolonged survival in NZBxW/F1 mice. TPC‐treated mice showed a significantly decreased level of proteinuria (P < 0·001) and anti‐dsDNA antibodies (P < 0·001) compared to PBS‐treated mice. Moreover, TPC and MP inhibited the production of the proinflammatory cytokines interferon IFN‐γ, interleukin IL‐1β and IL‐6 (P < 0·001) and enhanced expression of the anti‐inflammatory cytokine IL‐10 (P < 0·001). Finally, microscopy analysis of the kidneys demonstrated that TPC‐treated mice maintained normal structure equally to MP‐treated mice. These data indicate that the small molecule named TPC hinders lupus development in genetically lupus‐prone mice equally to methylprednisolone in most of the cases. Hence, TCP may be employed as a therapeutic potential for lupus nephritis.  相似文献   
102.
The self‐assembly and structure formation in binary blends of asymmetric polystyrene‐block‐poly(4‐vinylpyridine) diblock copolymers in different solvent systems and the bulk morphology of the blend films are studied by using dynamic light scattering, small‐angle X‐ray scattering, and transmission electron microscopy. In dilute solutions, the chains of pure diblock copolymers or binary blends of diblock copolymers having similar or different molecular weights remain as unimers, form common micelles in selective solvents or form unimers in coexistence with micelles in slightly selective solvents or solvent mixtures. The blends show mixing of the chemically similar blocks in the blend films and solutions at high concentrations. A single‐phase with common spherical morphology is formed in the blend films similar with the morphology of the individual components in the pure state. The characteristic length scale of the blends depends on the number average molecular weight following the typical scaling behavior of a strongly segregated block copolymer.

  相似文献   

103.
In this work, the influence of carbon nanotubes (CNTs) on the self‐assembly of nanocomposite materials made of cylinder‐forming polystyrene‐block‐poly(ethylene‐butylene)‐block‐polystyrene (SEBS) is studied. CNTs are modified with polystyrene (PS) brushes by surface‐initiated atom transfer radical polymerization to facilitate both their dispersion and the orientation of neighboring PS domains of the block copolymer (BCP) along modified CNT‐PS. Dynamic rheology is utilized to probe the viscoelastic and thermal response of the nanoscopic structure of BCP nanocomposites. The results indicate that nonmodified CNTs increase the BCP microphase separation temperature because of BCP segmental confinement in the existing 3D network formed between CNTs, while the opposite holds for the samples filled with modified CNT‐PS. This is explained by severely retarded segmental motion of the matrix chains due to their preferential interactions with the PS chains of the CNT‐PS. Moreover, transient viscoelastic analysis reveals that modified CNT‐PS have a more pronounced effect on flow‐induced BCP structural orientation with much lower structural recovery rate. It is demonstrated that dynamic‐mechanical thermal analysis can provide valuable insights in understanding the role of CNT incorporation on the microstructure of BCP nanocomposite samples. Accordingly, the presence of CNT has a significant promoting effect on microstructural development, comparable to that of annealing.  相似文献   
104.
Here, the periodically grafted linear–hyperbranched copolymers (LHGCs) based on polyethylene (PE) and hyperbranched polyglycidol is synthesized via acyclic diene metathesis polymerization and anionic ring‐opening multibranching polymerization. The chemical composition of LHGCs can be controlled by changing the amount of the initial monomer. For the first time this allows to control the architecture (composition and sequence distribution), in which the run length between adjacent hyperbranched pendants is exact along PE backbone. By comparing with aperiodically grafted analogues, the results clearly show the composition and the sequence distribution of LHGCs is identified as the major factor to influence the thermal stability, crystallinity as well as hydrophilicity.  相似文献   
105.
ES-62 is a phosphorylcholine (PC)-containing glycoprotein which is secreted by the rodent filarial nematode Acanthocheilonema viteae. A homologue exists in the human filarial nematode Brugia malayi and indeed PC is found attached to glycoproteins of many, if not all, filarial species. At concentrations equivalent to those found for PC-containing molecules in the bloodstream of parasitized humans, ES-62 is able to polyclonally activate certain protein tyrosine kinase and mitogen-activating protein kinase signal-transduction elements in B and T lymphocytes following in-vitro exposure. Although this interaction is insufficient to cause lymphocyte proliferation per se, it serves to desensitize the cells to subsequent activation of the phosphoinositide-3-kinase, protein kinase C and Ras mitogen-activating protein kinase pathways and hence also to proliferation via the antigen receptors. The active component of ES-62 appears to be PC, as the results obtained with ES-62 are broadly mimicked by PC conjugated to BSA or PC alone. Although PC can also be shown to desensitize B cells following in-vivo administration, not all cells are affected, as it is still possible to generate an antibody response. Dissection of this response indicates that it is of the Th2 type.  相似文献   
106.
用硅胶石蜡熔融共混体系来模拟熔铸炸药非均相体系的流变特性。通过改变硅胶的疏水化程度以及硅胶在体系中的质量分数来研究非均相体系流变学性能。改变硅胶与石蜡间的相互作用是调控非均相体系流变学性能最有效的方法之一。根据这一发现,制备了两亲性的梳型共聚物十八胺接枝马来酸酐 苯乙烯共聚物( SMAC ),通过改变十八胺的接枝度以及SMAC在非均相体系中的质量分数可以大大降低非均相体系的稳态黏度。  相似文献   
107.
Lu2O3:Eu3+ transparent, high density, and optical quality thin films were prepared using the sol-gel dip-coating technique, starting with lutetium and europium nitrates as precursors and followed by hydrolysis in an ethanol-ethylene glycol solution. Acetic acid and acetylacetonate were incorporated in order to adjust pH and as a sol stabilizer. In order to increment the thickness of the films and orient the structure, F127 Pluronic acid was incorporated during the sol formation. Structural, morphological, and optical properties of the films were investigated for different F127/Lu molar ratios (0–5) in order to obtain high optical quality films with enhanced thickness compared with the traditional method. X-ray diffraction (XRD) shows that the films present a highly oriented cubic structure <111> beyond 1073 K for a 3-layer film, on silica glass substrates. The thickness, density, porosity, and refractive index evolution of the films were investigated by means of m-lines microscopy along with the morphology by scanning electron microscope (SEM) and luminescent properties.  相似文献   
108.
以异丙基苯钾(n-Cumyl potassium)作引发剂,α-甲基丙烯酰氯为终止剂,用阴离子聚合方法合成了一系列不同分子量、不同组成的新型聚(苯乙烯-环氧乙烷)(疏水-亲水型)嵌段大单体[Poly(St-b-Eo)-MA magromer]。用红外光谱及核磁共振进行了鉴定并测定了它的数均官能度(?)_n,对大单体与苯乙烯、甲基丙烯酸甲酯和甲基丙烯酸在不同条件下的共聚反应也进行了研究。发现反应条件对大单体和烯类单体的共聚速率均有很大影响。  相似文献   
109.
高分子聚合物HFMC是一种良好的组织相容性材料,作者用5%HFMC一次性注入小鼠阴道0.8ml,通过交配实验,观察其避孕效果。结果表明:小鼠应用HFMC后可延迟自然复孕至分娩时间112~118天,与对照组30天相比,差异十分显著(P<0.001);人工复孕的分娩时间与对照组相比,无显著性差异(P>0.05)。  相似文献   
110.
采用含活性基团的聚二甲基硅氧烷与丙烯酸酯进行自由基共聚合,合成了自聚二甲基硅氧烷侧链的丙烯酸酯共聚物。采用IR,^1H-NMR,GPC等分析方法对共聚物结构和组成进行了表征。通过接触角和X-射线光电子能谱对共聚物的表面性能和表面组成进行了研究,并通过粘接性能和破坏面形貌对共聚物与金属铝材和加成型硅橡胶的粘接性进行了探讨。  相似文献   
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