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91.
Biological properties of interleukin-12 and its therapeutic use in persistent hepatitis B virus and hepatitis C virus infection 总被引:2,自引:0,他引:2
Summary. Interleukin (IL)-12 is a pleiotropic cytokine produced by antigen-presenting cells in response to diverse stimuli. IL-12 is a key molecule in the regulation of host's immune responses. In particular, IL-12 influences the balance between the T-helper cells type 1 (TH1 ) and type 2 (TH2 ); it modulates macrophage responses through the control of interferon-gamma synthesis by TH1 cells; and, suppresses IgE class antibody production (has a suppressive effect on allergic reactions) and promotes a shift in the IgG subclasses. IL-12 enhances resistance to several infectious diseases, is a powerful antitumor agent in vivo , and acts as a vaccine adjuvant. The biological properties of IL-12 point to the potential therapeutic use in persistent hepatitis B virus and hepatitis C virus infection. 相似文献
92.
Interleukin-5 has a specific role in various eosinophilic activities. It is the predominant cytokine produces by activated T-lymphocytes isolated from patients with idiopathic hypereosinophilic syndrome. We studied a young patient suffering from idiopathic hypereosinophilic syndrome who presented with Horner's syndrome, peripheral neuropathy and skin ulcers. The IL-5 gene expression by CD4+ T-lymphocytes and the peripheral eosinophil count were raised. The skin ulcers continued to deteriorate despite a swift reduction of the IL-5 gene expression and peripheral eosinophil count following systemic corticosteroid treatment. We suggest that peripheral eosinophilia may not be responsible for the damage in skin lesions and more aggressive treatment may be required. 相似文献
93.
Christian Foged Christer Halldin Christian Loc’h Bernard Mazière Stefan Pauli Mariannick Maziére Holger C. Hansen Tetsuya Suhara Carl-Gunnar Swahn Per Karlsson Lars Farde 《European journal of nuclear medicine and molecular imaging》1997,24(10):1261-1267
NNC 13-8241 has recently been labelled with iodine-123 and developed as a metabolically stable benzodiazepine receptor ligand
for single-photon emission computed tomography (SPECT) in monkeys and man. NNC 13-8199 is a bromo-analogue of NNC 13-8241.
This partial agonist binds selectively and with subnanomolar affinity to the benzodiazepine receptors. We prepared 76Br labelled NNC 13-8199 from the trimethyltin precursor by the chloramine-T method. Carbon-11 labelled NNC 13-8199 was synthesised
by N-alkylation of the nitrogen of the amide group with [11C]methyl iodide. Positron emission tomography (PET) examination with the two radioligands in monkeys demonstrated a high uptake
of radioactivity in the occipital, temporal and frontal cortex. In the study with [76Br]NNC 13-8199, the monkey brain uptake continued to increase until the time of displacement with flumazenil at 215 min after
injection. For both radioligands the radioactivity in the cortical brain regions was markedly reduced after displacement with
flumazenil. More than 98% of the radioactivity in monkey plasma represented unchanged radioligand 40 min after injection.
The low degree of metabolism indicates that NNC 13-8199 is metabolically much more stable than hitherto developed PET radioligands
for imaging of benzodiazepine receptors in the primate brain. [76Br]NNC 13-8199 has potential as a radioligand in human PET studies using models where a slow metabolism is an advantage.
Received 19 April and in revised form 10 June 1997 相似文献
94.
目的 研究冠心病患者心肌缺血情况下循环中白细胞介素-6(IL-6)和脂蛋白(a)[LP(a)]水平的关系和临床意义。方法 用ELISA分析试剂盒检测62例冠心病患者和50例健康对照者血浆IL-6,用免疫透射比浊法检测血滑LP(a),并对心电图(EKG)ST段的情况进行比较。结果 冠心病组血浆IL-6和血清LP(a)水平均较健康对照组显著增高(P<0.01)。与健康对照组相比,ST段异常组和ST段正常组血浆IL-6水平均显著增高(P<0.01);ST段异常组血浆LP(a)水平显著增高(P<0.01),ST段正常组血清LP(a)水平有所增高,但无统计学意义(P>0.05)。ST段异常组血浆IL-6和血清LP(a)水平均显著高于ST段正常组(P<0.05,P<0.01)。冠心病患者血浆IL-6和血滑LP(a)水平存在显著的相关性(P<0.05)。结论 冠心病患者循环中IL-6和LP(a)水平显著升高,高水平IL-6和LP(a)可能反映血管和心肌损伤的发生,LP(a)的增加可能与IL-6刺激肝脏合成LP(a)增加有关。 相似文献
95.
大鼠坐骨神经慢性挤压性损伤后痛阈和血清IL-6的变化及相关性研究 总被引:2,自引:0,他引:2
目的:通过大鼠坐骨神经慢性挤压伤(CCI)神经性疼痛模型的热敏变化及血清中IL-6含量的变化,探讨血清IL-6在神经性疼痛形成中的作用及可能机制.方法:36只250~300g的健康雄性Wistar大鼠,在戊巴比妥钠麻醉下于大腿中部暴露坐骨神经并作结扎,取对侧大腿坐骨神经暴露作为模拟对照(B组).术后1,3,5,7,9,11,13,15 d测定大鼠(n=12)两侧后爪对热敏阈值的变化.于术后第15 d处死大鼠,取血清,ELISA法测定IL-6浓度.结果:大鼠双侧后爪(CCI和B)的收缩潜伏期在术后第3,5,7,9,11,13,15 d有显著差异;CCI组血清IL-6与对照组比较有显著差异.结论:IL-6与大鼠坐骨神经慢性挤压性损伤后出现的神经源性疼痛过敏有关. 相似文献
96.
在体外试验中研究了azimexon对小鼠脾细胞增殖以及白细胞介素2(IL-2)的影响。IL-2活性采用小鼠胸腺细胞增殖法和CTLL细胞增殖法测定。结果表明:azimexon单独不能增加脾细胞增殖和产生IL-2,但对亚适量ConA或LPS诱导的脾细胞增殖和产生IL-2有明显协同作用。 相似文献
97.
98.
目的探讨高糖不同浓度刺激或抑制剂对肾小球系膜细胞表达细胞周期负控蛋白P27的影响.方法不同浓度高糖(5.5 mmol/L和25mmol/L、内皮素-1(10-7mol/L)、白介素-13(10 ng/ml和100 ng/ml)作用于培养的系膜细胞.流式细胞仪检测系膜细胞P27表达水平.结果5.5mol/L浓度组在不同时间P27表达为5.10±0.94和3.84±0.81,较对照级明显降低(P<0.001),而25 mmol/L浓度组在不同时间P27表达为26.82±3.15和30.88±3.68,较对照组明显升高.内皮素-1刺激14 h和18 h后P27的表达分别为14.76±1.49和12.18±1.30,与对照组比较有明显差异(P<0.05,P<0.05).IL-13 10 ng/ml浓度组和100 ng/ml浓度组P27表达为46.74±3.52和23.8±2.56,对对照组比较有明显差异(P<0.001,P<0.05),不同浓度组之间有显著差异(P<0.01).结论细胞周期调节负控蛋白P27在调节系膜细胞增殖过程中起重要作用. 相似文献
99.
《Journal of labelled compounds & radiopharmaceuticals》2003,46(7):605-611
JTT‐501 specifically labelled with 13C was obtained via a four‐step synthesis at an isotopic enrichment level of 99% and in 14% overall chemical yield starting from 4‐hydroxy‐[ring‐U‐13C6]benzaldehyde (3) . The hydrogenation of [13C6]JTT‐501 over Pd/C gave [13C6]JTP‐20604 in 90% chemical yield. Copyright © 2003 John Wiley & Sons, Ltd. 相似文献
100.
M. M. Moens A. V. Mertens L. S. De Clerck H. P. Van Bever C. H. Bridts W. J. Stevens 《Pediatric allergy and immunology》1993,4(2):89-92
In patients with allergic asthma and rhinitis high numbers of hypodense eosinophils (HE) have been demonstrated. In a previous study we reported that asthmatic and healthy children had more HE than their adult counterparts. We assumed that this might, in part, he due to the presence of immature eosinophils in children. To distinguish between immature and activated eosinophils, determination of eosinophil cationic protein (ECP) might be interesting as it is known that high serum levels of ECP are associated with increased activation of eosinophiis. In this study we determined (he levels of ECP in scrum in asthmatic and healthy children and adults trying to distinguish activated from immature eosinophils. We found that ECP levels were not increased in children (healthy and asthmatic) compared to adults (healthy and asthmatic). This supports the hypothesis that increased numbers of HE in childhood are, at least in part, immature eosinophils. Nevertheless, we could confirm that inflammation was present in children because soluble interleukin-2-receptor (slL-2R), a marker of lymphocyte activation, was higher in asthmatic children as compared to healthy children. IL-6, a marker of macrophage/monocyte activation, was not different in the different patient groups. We conclude that although signs of inflammation are present in childhood asthma, the increased numbers of HE in children are in part due to the presence of immature eosinophils. 相似文献