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991.
本文应用植物血凝素(PHA)检测了乌市维汉族学龄儿童的细胞免疫功能。结果表明,汉族儿童的PHA红斑直径均值高于维族,不论维汉族男女生均以9~10岁年龄段PHA红斑均值最大,并有随年龄增加而下降的趋势。同时对缺铁性贫血、生长发育水平及营养状况对细胞免疫功能的影响进行了初步探讨。 相似文献
992.
Diabetic patients are at increased risk of cardiovascular disease, particularly when proteinuria is present. Lipoprotein(a)[Lp(a)] levels were assessed in 37 patients with insulin dependent (IDDM) and in 75 patients with non-insulin dependent (NIDDM) diabetes who showed varying degrees of proteinuria and glycaemic control. Median Lp(a) in 112 diabetic patients was significantly greater than in 116 healthy controls (113 vs 48 mg/L; p <0.01). 86 of the patients had first morning urine albumin concentration < 30 mg/L (normoalbuminuria = NA), 16 patients 30–200 mg/L (microalbuminuria = MA) and ten patients < 200 mg/L (albuminuria = ALB). There was no significant difference in median Lp(a) concentration between the three groups (NA = 108, MA = 163, ALB = 98 mg/L; p > 0.5). No significant difference in median Lp(a) concentration was found between patients with IDDM, NIDDM treated with insulin, or NIDDM treated with oral agents and/or diet (120, 98, 115 mg/L respectively; p > 0.7). When the 86 NA patients were divided on the basis of median fructosamine concentration (357 umol/L), no significant difference was found in median Lp(a) levels between those grouped below or above this median (98 mg/L vs 118 mg/L; p < 0.5). Across all diabetics studied there was no significant correlation present between Lp(a) and urinary protein or glycaemic control. These cross-sectional results suggest that median Lp(a) concentration is increased in both IDDM and NIDDM patients, but this increase is not related to the degree of proteinuria or short-term glycaemic control. 相似文献
993.
We investigated the distribution of prion protein (PrP) in 14 German patients with sporadic Creutzfeldt-Jakob disease (CJD) and compared it with that observed in Japanese patients. Immunohistochemical study revealed diffuse gray matter stainings including synaptic structures in all cases. In addition, 4 patients showed plaque-type deposition which was very rarely observed among sporadic Japanese patients without known mutation of the PrP gene but with valine at codon 129. A higher incidence of PrP plaques in German sporadic CJD may be related to the racial difference in the PrP gene. 相似文献
994.
P. E. Roland C. J. Graufelds J. WÎhlin L. Ingelman M. Andersson A. Ledberg J. Pedersen S. kerman A. Dabringhaus K. Zilles 《Human brain mapping》1994,1(3):173-184
We present the new computerized Human Brain Atlas (HBA) for anatomical and functional mapping studies of the human brain. The HBA is based on many high-resolution magnetic resonance images of normal subjects and provides continuous updating of the mean shape and position of anatomical structures of the human brain. The structures are transformable by linear and nonlinear global and local transformations applied anywhere in 3-D pictures to fit the anatomical structures of individual brains, which, by reformatting, are transformed into a high-resolution standard anatomical format. The power of the HBA to reduce anatomical variations was evaluated on a randomized selection of anatomical landmarks in brains of 27 young normal male volunteers who were different from those on whom the standard brain was selected. The HBA, even when based only on standard brain surface and central structures, reduced interindividual anatomical variance to the level of the variance in structure position between the right and left hemisphere in individual brains. © 1994 Wiley-Liss, Inc. 相似文献
995.
本文观察黑木耳对实验性动脉粥样硬化(AS)家兔AS病变及有关生化指标的影响。实验结果,黑木耳有降低血浆胆固醇(TC)、过氧化脂质(LPO)、血栓素A_2(TXA_2)的含量,提高前列环素/血栓素A_2(PGI_2/TXA_2)比值,减轻AS病变的作用。表明黑木耳具有抗AS作用。其机理可能是通过降血TC,保护动脉内膜,抑制血小板聚集,并由此抑制TXA_2合成;血TC降低亦可减少脂质过氧化,从而使环氧化酶、TXA_2合成酶活性降低,TXA_2合成减少。黑木耳通过以上途径维系PGI_2/TXA_2平衡,保护血管完整性的内环境相对稳定,对抗动脉粥样硬化的发生。 相似文献
996.
Serum levels of free insulin-like growth factor (IGF)-I were measured by
immunoradiometric assay (IRMA) in fasting sera of 137 normal boys and 120 normal girls
aged from 8 to 15 yr to study relationships between free IGF-I levels and ages, total
IGF-I, IGF binding protein (IGFBP)-1, IGFBP-3, and acid-labile subunit (ALS) levels. In
both sexes, serum free IGF-I levels and the ratios of free IGF-I to total IGF-I were
significantly higher in the pubertal age groups than in the prepubertal age groups. Serum
levels of free IGF-I showed a significant positive correlation with those of total IGF-I,
IGFBP-3 and ALS, while they showed a significant negative correlation with those of
IGFBP-1. These observations suggest that increase in serum free IGF-I levels during
puberty is caused by a dramatic increase in total IGF-I, rather than IGFBP-3, and a
decrease in IGFBP-1. Also, high free IGF-I levels may play an important role in pubertal
growth spurt. 相似文献
997.
神经网络分析方法用于心脏病诊断的研究 总被引:2,自引:1,他引:1
神经网络可以很好的拟合任意的非线性函数。我们从 QRS波群的高频三维频谱中提取出一些定量的特征参数 ,用神经网络的方法对这些参数进行有监督的学习训练 ,最终能在由这些特征参数张成的 m维空间中构建出一个 m维的曲面来区分病人和健康人的 QRS波群高频三维频谱 ,从而使得训练后的网络能基于 QRS波群的高频三维频谱自行诊断出病人和健康人 相似文献
998.
以丁二酸酐(SA)为交联剂研究了端羟基超支化聚(胺-酯)(HPAE)的交联反应和交联膜的制备。结果表明:SA与HPAE的交联反应分为两个阶段,可以采用溶液法低温涂膜及高温交联得到HPAE/SA交联膜;改变SA的用量可控制膜的交联度,HPAE/SA交联膜的拉伸强度随SA用量的增大而提高,最高可达59.60 M Pa,膜表面的水接触角小于74.3°。 相似文献
999.
The effects of carbocyclic thromboxane A(2) (cTXA(2); 10(-6) mol L(-1)) on membrane potential and cytosolic Ca(2+) concentration were measured with the whole-cell patch-clamp or the fura-2 method, respectively, at rat myenteric ganglia. cTXA(2) caused a hyperpolarization of myenteric neurones from -19.3 +/- 2.5 to -29.3 +/- 2.3 mV. In addition, the eicosanoid potentiated the carbachol-induced depolarization from 4.2 +/- 1.0 mV under control conditions to 11.1 +/- 1.1 mV in the presence of the cTXA(2) (n = 9). The hyperpolarization was abolished by internal application of CsCl (140 mmol L(-1)), a non-selective blocker of K(+) channels, or EGTA (11 mmol L(-1)in the pipette solution), a chelator of intracellular Ca(2+). A similar inhibition was observed in the presence of charybdotoxin (10(-7) mol L(-1)). Fura-2 imaging experiments revealed a cTXA(2)-evoked increase in the intracellular Ca(2+) concentration as indicated by a rise in the fura-2 ratio signal. This response was mediated by a release of Ca(2+) from intracellular stores as sarcoplasmic-endoplasmic reticulum Ca(2+)-ATPase blockade with cyclopiazonic acid (5 x 10(-5) mol L(-1)) completely abolished the response to cTXA(2). A similar inhibition was observed after blockade of phospholipase C with U-73122 (10(-5) mol L(-1)). These results suggest an activation of Ca(2+)-activated K(+) channels by cTXA(2) after stimulation of phospholipase C. 相似文献
1000.