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排序方式: 共有10000条查询结果,搜索用时 15 毫秒
61.
Kevin Brooks Hanem Hasan Sridhar Samineni Venu Gangur Wilfried Karmaus 《Pediatric allergy and immunology》2007,18(7):621-624
Placental p,p'-dichlorodiphenyldichloroethylene (p,p'-DDE) concentration and cord blood atopic markers were determined in 19 neonates. Increased placental p,p'-DDE was associated with a statistically significant increase in cord plasma interleukin (IL)-13. Furthermore, both cord plasma IL-4/interferon (IFN)-gamma and IL-13/IFN-gamma ratios were significantly positively associated with placental p,p'-DDE concentration. 相似文献
62.
目的:观察皮肤成纤维细胞在某些条件下释放的细胞因子对肝细胞急性期反应的影响。方法:用细菌脂多糖孵育人的皮肤成纤维细胞,测定培养液中IL-1β和IL-6浓度;并用不同浓度和组合的细胞培养液、重组IL-6(rhIL-6)和地塞米松孵育鼠肝瘤H4细胞,观察白蛋白、α1酸糖蛋白、α1抗胰蛋白酶和转铁蛋白mRNA表达的变化。结果:发现细菌脂多糖刺激成纤维细胞合成IL-6,而地塞米松抑制这一作用。IL-6和细菌脂多糖孵育的成纤维细胞培养液抑制白蛋白mRNA的表达,成纤维细胞培养液。地塞米松促进α1酸糖蛋白、α1抗胰蛋白酶mRNA的表达、单用IL-6即能抑制白蛋白和转铁蛋白mRNA的表达,地塞米松加强IL-6和成纤维细胞培养液的抑制作用。结论:(1)细菌脂多糖处理的成纤维细胞能够分泌IL-6,但不分泌11-1β;(2)成纤维细胞产生的细胞因子能够调节急性期反应时的肝脏蛋白合成;(3)地塞米松抑制成纤维细胞产生IL-6,但加强其刺激急性期反应的能力。 相似文献
63.
BACKGROUND: Reduced Th1 and elevated Th2 cytokine responses are considered to be a principal mechanism in the generation of the inflammation leading to the manifestations of atopic disease in the skin of atopic dermatitis and in the airways of asthma. If reduced Th1 and elevated Th2 responses are principal determinants of the manifestation of atopic disease it might be expected that subjects with established disease would exhibit differences in their cytokine profiles as compared with atopic patients without clinical disease. OBJECTIVE: To determine whether asymptomatic atopic children exhibit a cytokine imbalance similar to that seen in patients with established atopic disease or if they behave like non-atopic controls. Cytokine responses in a group of children with elevated IgE but no clinical manifestations of disease, atopic children with established disease and non-atopic controls were compared. METHODS: We examined allergen-induced (house dust mite, HDM, rye grass pollen and RYE) cytokine responses in parallel with polyclonal (staphylococcal enterotoxin B, SEB) cytokine responses in a group of children with elevated serum IgE levels without current or past evidence of atopic disease (median age 6.6 years) and compared these with a non-atopic control group (median age 6.5 years) and a group of children with atopic disease (median age 6.7 years). RESULTS: Symptomatic atopic children had reduced SEB-induced IFN-gamma and increased SEB-induced IL-4 and IL-5 as compared with non-atopic controls. In contrast, SEB-induced IFN-gamma, IL-4 and IL-5 production in asymptomatic atopics was not significantly different from the non-atopic control subjects. Allergen-induced Th1 (IFN-gamma) and Th2 (IL-5 and IL-13) cytokine production was increased in both symptomatic atopics and asymptomatic atopics when compared with non-atopic controls. CONCLUSION: The defect in polyclonally induced IFN-gamma production was associated with the clinical manifestation of atopic disease but not the atopic stateper se. This suggests that the global reduction in IFN-gamma is the key determinant of the development of overt atopic disease. In contrast, elevated allergen-induced Th2 cytokine responses in children related to the atopic state per se irrespective of the presence of clinical atopic disease. 相似文献
64.
Philip F. Halloran Joan Urmson Vido Ramassar Anette Melk Lin-Fu Zhu Brendan P. Halloran R. Chris Bleackley 《American journal of transplantation》2004,4(5):705-712
Organ allograft rejection is strongly associated with the presence of alloreactive cytotoxic T cells but the role of cytotoxicity in the pathologic lesions is unclear. Previous studies showed that the principal lesions of kidney rejection - interstitial infiltration, tubulitis, and endothelial arteritis - are T-cell-dependent and antibody-independent. We studied the role of cytotoxic granule components perforin and granzymes A and B in the evolution of the T-cell-mediated lesions of mouse kidney transplant rejection. By real-time RT-PCR, allografts rejecting in wild-type hosts at days 5, 7, 21, and 42 showed massively elevated and persistent expression of perforin and granzymes A and B, but evolution of tubulitis and arteritis did not correlate with increasing granzyme or perforin expression. Allografts transplanted into hosts with disrupted genes for perforin or granzymes A and B showed no change in tubulitis, arteritis, or MHC induction. Thus the development of the histologic lesions diagnostic of T-cell-mediated kidney transplant rejection are associated with but not mediated by perforin or granzyme A or B. Together with previous graft survival studies, these results indicate that the granule-associated cytotoxic mechanisms of T cells are not the effectors of T-cell-mediated allograft rejection. 相似文献
65.
J. A. Dunstan J. Roper L. Mitoulas† P. E. Hartmann† K. Simmer S. L. Prescott 《Clinical and experimental allergy》2004,34(8):1237-1242
BACKGROUND: Breast milk contains many immunomodulatory factors (soluble CD14 (sCD14), IgA and cytokines) with the potential to influence infant immune development. OBJECTIVE: To determine if changes in breast milk omega-3 polyunsaturated fatty acid (n-3 PUFA) composition as a result of maternal dietary fish oil supplementation during pregnancy can modify levels of these immunological parameters in breast milk. METHOD: In a randomized controlled trial, 83 atopic women received either 4 g fish oil capsules (containing 3.7 g n-3 PUFA) (n = 40) or 4 g olive oil capsules (n = 43) from 20 weeks gestation until delivery. Breast milk was collected 3 days post-partum and fatty acids were analysed by gas liquid chromatography and IgA, sCD14 and cytokines (IL-5, IL-6, IL-10, TNF-alpha and IFN-gamma) were quantitated by ELISA or time resolved fluorescence (TRF). RESULTS: Omega-3 docosahexaenoic acid (DHA; 22:6n-3) and eicosapentaenoic acid (EPA; 20:5n-3) levels were significantly higher (P < 0.001) in breast milk from women supplemented with fish oil (n = 33, DHA mean 1.15%, SD 0.47% and EPA mean 0.16%, SD 0.07%) than in samples from the control group (n = 40, DHA mean 0.50%, SD 0.17% and EPA mean 0.05%, SD 0.02%). Breast milk arachidonic acid (AA; 20:4n-6) levels were significantly lower (P = 0.045) in the fish oil group (mean 0.55%, SD 0.12%) compared with the control group (mean 0.61%, SD 0.14%). Breast milk IgA was positively correlated with DHA (P = 0.046) and 22:5n-3 (P = 0.003), but inversely correlated with linoleic acid (LA; 18:2n-6) (P=0.034). Levels of sCD14 were also positively correlated with 22:5n-3 (P=0.009). Cytokines involved in IgA synthesis (IL-10 and IL-6) were also significantly correlated with both IgA and n-3 PUFA levels, although there were no differences in the levels of breast milk IgA, sCD14 or cytokines between study groups. CONCLUSION: Supplementation with fish oil during pregnancy significantly alters early post-partum breast milk fatty acid composition. omega-3 PUFA levels were positively associated with IgA and sCD14 levels, suggesting a relationship between fatty acid status and mucosal immune function. 相似文献
66.
不同脑保护方法中炎症反应对脑组织的影响 总被引:1,自引:1,他引:0
目的 通过观察体外循环中采用不同脑保护方法时脑组织中各种炎性细胞因子的变化,探讨脑保护对炎症反应的影响。方法 将18只健康成年杂种犬随机均分为3组:常温体外循环组(normothermic cardiopulmonary bypass,NCPB组),深低温停循环组(deep hypothermic circulatory arrest,DHCA组),深低温停循环+间断选择性顺行性脑灌注组(intermittent selective antegrade cerebral perfusion,ISACP,DHCA+ISACP组)。术后检测犬脑组织的含水量,分离并取出海马,制备脑组织匀浆,采用放射免疫法测定白细胞介素-1β(IL-1β)和肿瘤坏死因子-α(TNF—α)的含量。在透射电子显微镜(TE)下检测海马脑组织的细胞形态学变化。结果 DHCA组的IL-1β和TNF—α含量明显高于NCPB组和DHCA+ISACP组(P〈0.01),但NCPB组与DHCA+ISACP组间比较差别无统计学意义(P〉0.05);TNF—α和IL-1β含量与脑水肿的程度呈正相关(r=0.987,0.942;P〈0.01)。TE检查显示DHCA组超微结构破坏较严重,而NCPB组和DHCA+ISACP组破坏较轻。结论 长时间DHCA会造成脑损伤,DHCA+ISACP有一定的脑保护作用,IL-1β和TNF—α在长时间DHCA中对脑损伤起一定的作用。 相似文献
67.
68.
T Germann F Mattner A Partenheimer E Schmitt A B Reske-Kunz H G Fischer E Rüde 《International immunology》1992,4(7):755-764
The ability of macrophages to stimulate immune responses is heterogeneous and may have influence on the type of the developing immune response. Therefore, in an attempt to define different functional states of mouse macrophages, we made use of the two macrophage growth factors: macrophage colony stimulating factor (M-CSF) and granulocyte macrophage colony stimulating factor (GM-CSF). Generation of macrophages from freshly isolated bone marrow cells in the presence of GM-CSF results in a population expressing profound antigen presenting function for mouse TH1 cells, resulting in strong lymphokine production and proliferation of the T cells. Furthermore, high amounts of a novel soluble cytokine active on mouse TH1 cells are generated during the interaction of TH1 cells with macrophages elicited with GM-CSF. In contrast, macrophages grown from bone marrow cells for at least 14 days in the presence of M-CSF express only minimal antigen-presenting function for TH1 cells. Treatment of such macrophages for 24 h with either IFN-gamma or GM-CSF allows the distinction between two further functional states. Those treated with IFN-gamma efficiently presented antigen towards TH1 cells. The T cells produced large amounts of lymphokines and proliferate well. However, synthesis of the novel soluble cytokine (active on TH1 cells) was not detectable. The generation of this mediator requires a short-term treatment with GM-CSF of macrophages developed in the presence of M-CSF prior to their interaction with TH1 cells. 相似文献
69.
R. D. Myers F. J. Lopez-Valpuesta F. J. Minano M. H. Wooten V. S. Barwick S. D. Wolpe 《Journal of neuroscience research》1994,39(1):31-37
The chemokines, macrophage inflammatory protein-1 (MIP-1) and its subunit MIP-1β, induce an intense fever in the rat when they are injected directly into the anterior hypothalamic, pre-optic area (AH/POA), a region containing thermosensitive neurons. The purpose of this study was to compare the central action on body temperature (Tb) of MIP-1β with that of interleukin-6 (IL-6), which also has been implicated in the cerebral mechanism underlying the pathogenesis of fever. Following the stereotaxic implantation in the AH/POA of guide cannulae for repeated micro-injections, radio transmitters which monitor Tb continuously were inserted intraperitoneally in each of 15 male Sprague-Dawley rats. Each micro-injection was made in a site in the AH/POA in a volume of 1.0 μl of pyrogen-free artificial CSF, recombinant murine MIP-1β, or recombinant human IL-6. MIP-1β in a dose of 25 pg evoked an intense fever characterized by a short latency, a mean maximum rise in Tb of 2.4 ± 0.21°C reached by 3.7 ± 0.42 hr, and a duration exceeding 6.5 hr. Injected into homologous sites in the AH/POA, IL-6 induced a dose dependent fever of similar latency and a mean maximal increase in Tb of 1.2 ± 0.25°C, 1.8 ± 0.15°C, and 2.1 ± 0.22°C and duration of 6.2 ± 1.28 hr, 6.7 ± 0.49 hr, and 6.8 ± 0.65 hr when given in doses of 25, 50, and 100 ng, respectively. These results show that MIP-1β and the highest dose of IL-6 induce a fever of comparable intensity, but MIP-1β exerts its action in a much lower concentration. Thus, the de novo synthesis and subsequent action of the MIP-1 family of cytokines on neurons of the AH/POA in response to a pyrogen challenge apparently play a functional role in the pathogenesis of fever. Further, the endogenous activity of IL-6 in the hypothalamus which is enhanced in response to a lipopolysaccharide also may reflect its essential part in the acute phase response to a bacterial challenge. Copyright © 1994 Wiley-Liss, Inc. 相似文献
70.
Inflammatory mediators and the destruction of bone 总被引:3,自引:0,他引:3
Gregory R. Mundy 《Journal of periodontal research》1991,26(3):213-217
Bone is remodelled by the coordinated actions of osteoclasts and osteoblasts. Cellular remodelling occurs in discrete packets of bone, and is regulated by local cytokines produced in the environment of the remodelling cells. These cytokines are secreted by immune cells and by bone cells. In addition, some growth regulatory factors are incorporated into the noncollagenous bone matrix and are released in an active form when bone is stimulated to resorb. Complex interactions between these cytokines and their target cells are responsible for the normal delicate balance between bone resorption and bone formation, and disorders of bone loss are due to imbalances between the rates of resorption and formation. 相似文献