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81.
P38MAPK抑制剂对缺血/再灌注大鼠肾脏功能损伤的保护作用 总被引:1,自引:0,他引:1
目的:观察P38MAPK抑制剂对缺血/再灌注大鼠肾脏功能损伤的保护作用。方法:夹闭肾动脉制遣大鼠肾脏缺血/再灌注损伤动物模型,静脉注射P38MAPK抑制剂阻断P38MAPK信号转导通路,测量其对肾功能及细胞因子含量的影响。结果:肾脏和血浆中TNF—α和IL-β含量随缺血/再灌注时间的延长而升高,肾功能损伤也随缺血/再灌注时间的延长而加重。应用P38MAPK抑制剂可显著降低TNF-α和IL-β含量,对缺血/再灌注所致的肾功能损伤具有明显改善作用。结论:P38MAPK抑制剂可通过抑制致炎因子的产生而减轻缺血/再灌注所致的大鼠肾脏功能损伤。 相似文献
82.
Terue Suzuki Masatoyo Kagoshima Masahiro Shibata Niro Inaba Sadayoshi Onodera Tetsuaki Yamaura Hideyo Shimada 《Digestive diseases and sciences》1997,42(6):1242-1254
The effect of chemical deafferentation, vagotomy(VGX), and gangliosympathectomy (GSX) on the density offibers containing calcitonin gene-related peptide (CGRP)and substance P (Sub.P) in the rat gastric wall was studied. Chemical deafferentation bycapsaicin abolished the density of CGRP-immunoreactive(IR) fibers, not Sub.P-IR fibers. Ten days after VGX,the density of CGRP-IR or Sub.P-IR fibers in the mucosa was largely reduced, while no reductionof CGRP-IR and Sub.P-IR fibers was seen in submucosaland muscular layers. GSX significantly reduced thedensity of CGRP-IR fibers in the mucosa and caused a moderate decrease in the fibers in submucosaland muscular layers. Pretreatment with6-hydroxydopamine, a neurotoxin for noradrenergicnerves, did not affect the density of CGRP-IR fibers inthe gastric wall. The density of Sub.P-IR fibers in thegastric wall was not affected by GSX. These studiesindicate that the CGRP-IR and Sub.P-IR fibers in themucosa are susceptible to extrinsic nerve denervation compared with those in the submucosa and musclelayers, that a major portion of the CGRP-IR fibers inthe mucosa is of both vagal and spinal origin, and thata major portion of the Sub.P-IR fibers in the mucosa is of vagal origin. Furthermore, thepresent results support that CGRP-IR fibers, notSub.P-IR fibers, in the rat stomach arecapsaicin-sensitive. 相似文献
83.
84.
选择经典的实验指标,对海风藤及其3种代用品山Ju,石楠藤有毛Ju的药理作用进行了比较研究,结果表明海风藤,山Ju和毛Ju在抗炎,镇痛和抗血小板聚集方面均有效,其中海风藤作用最强,其次为山Ju,毛Ju石楠藤没有明显的抗炎作用,其抗血小板聚集及止痛作用稍强于毛Ju。 相似文献
85.
A. V. Filatov S. A. Prokof'ev V. V. Shcherbukhin 《Bulletin of experimental biology and medicine》1992,114(5):1656-1659
Institute of Immunology, Ministry of Health of Russian. (Presented by Academician of the Russian Academy of Medical Sciences R. V. Petrov.) Translated from Byulleten Éksperimental'noi Biologii i Meditsiny, Vol. 114, No. 11, pp. 506–508, November, 1992. 相似文献
86.
87.
Mitsuhiko Yanagisawa Rumiko Hosoki Masanori Otsuka 《European journal of pharmacology》1992,220(2-3):111-117
We have developed an isolated spinal cord-skin preparation of the newborn rat. The spinal cord together with a piece of skin connected to the cord by the saphenous nerve was isolated from 1- to 4-day-old rats and separately superfused with artificial cerebrospinal fluid in two neighbouring chambers. Potentials were recorded extracellularly from the third lumbar ventral root. Application of capsaicin (0.5-2 μM) or KCl (60–350 mM) with brief pressure pulses to the perfusion bath of the skin evoked a depolarizing response of 20- to 40-s duration in the ventral root. The response was depressed by [Met5]enkcphalin (0.03–3 μM). morphine (0.1–2 μM) and a tachykinin antagonist, [D-Arg1,D-Trp7,9,Leu11] substance P (spantide), 1–10 μM), applied to the spinal cord by superfusion, whereas the response was augmented by centrally administered calcitonin gene-related peptide (0.1–0.2 μM) or bicuculline (0.5–1 μM). 相似文献
88.
W N Kühn-Velten 《Andrologia》1992,24(2):109-111
In addition to the well-known control circuits involved in the regulation and adaptation of testicular androgen biosynthesis, it is proposed that two new control strategies are involved in the maintenance of steady-state testosterone secretion rates by testicular Leydig cells. Cytochrome P450XVII (steroid-17 alpha-monooxygenase/steroid-17,20-lyase), one key enzyme in steroid hormone biosynthesis, responds to external human choriogonadotropin stimulation with an oxygen-dependent and substrate flux-dependent inactivation and decomposition, and increased substrate availability decreases the efficiency of androgen formation in favour of abortive intermediate leakage. These results are discussed as a paradigm of substrate-dependent modulation of cytochrome P450 activities. 相似文献
89.
细胞色素P450调节剂对DNA加合物形成的影响 总被引:1,自引:0,他引:1
人羊膜上皮细胞FL系分别接触a-萘黄酮(0.6mmol·L ̄(-1))β-萘黄酮(20pmol·L ̄(-1))24h后,再用苯并(a)芘[B(a)P,10umol·L ̄(-1)]处理24h,用32P后标记技术测定以B(a)-DNA加合物。结果发现,阳性对照组,a-萘黄酮预处理组及β-萘黄酮预处理组加合物的量分别为(加合物个数/10’个核苷酸):4.7±0.2(100%),1.8±0.9(38.3%),16.0±2.2(340.1%).该实验结果直接显示了纳胞色素P450调节剂对肿瘤发生影响的作用水平。亦为药物对致癌物代谢影响的研究提供了一种方法. 相似文献
90.
Event-related potential (ERP), electroencephalographic (BEG), and behavioral data were collected from squirrel monkeys (Saimiri sciureus) in a 90−10 auditory oddball paradigm. Background or target tones were presented once every 2 s, and responses to the targets were rewarded. ERPs were recorded from epidural electrodes following systemic administration of clonidine (0.1 mg/kg) or a saline placebo. EEG power spectra and behavioral performance were assessed simultaneously as indices of behavioral state. Clonidine significantly decreased the area and increased the latency of a P300-like potential. The amplitudes and areas of the earlier P1, N1, and P2 components and a later slow wave-like potential were not reduced, nor were their latencies altered. Clonidine produced increased EEG power in the alpha range (7.5–12 Hz) and decreased power in the upper beta range (20–40 Hz) but did not affect performance in the oddball task. Because two major effects of clonidine are to substantially reduce activity in the noradrenergic nucleus locus coeruleus (LC) and to reduce norepinephrine (NE) release from axons, the present results support the hypothesis that the LC and its efferent projection system are important in modulating the activity of P300-like potentials. 相似文献