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31.
Mechanism of skin penetration-enhancing effect by laurocapram. 总被引:6,自引:0,他引:6
K Sugibayashi S Nakayama T Seki K Hosoya Y Morimoto 《Journal of pharmaceutical sciences》1992,81(1):58-64
In order to clarify the mechanism of action of laurocapram (Azone) on the skin permeation of drugs, the following experiments were done. First, the effect of Azone on the skin components was compared with that of other penetration enhancers. Azone markedly fluidized liposomal lipids (as a model lipid system) compared with other enhancers. Ethanol extracted large amounts of the stratum corneum lipids, whereas Azone did not. These results suggest that the effect of Azone on the lipids in the stratum corneum is not the same as that of ethanol. In addition, ethanol increased the amount of free sulfhydryl (SH) group of keratin in the stratum corneum, whereas Azone did not directly affect the stratum corneum protein. Azone increased water content in the stratum corneum, as measured by skin conductance. This effect might be a reason for the action of Azone. For further understanding, the enhancing effects of Azone on the skin permeation of several model compounds (alcohols, sugars, and inorganic ions) were compared with the effects of pretreatment with distilled water, which was thought to increase water-holding capacity, and pretreatment with ethanol, which was thought to affect the lipids and protein in the skin barrier (i.e., stratum corneum). Pretreatment with water or ethanol enhanced skin permeation of hydrophilic compounds, whereas they decreased that of octanol, a hydrophobic compound. The tendency of Azone to increase or decrease the skin permeation rate of most compounds was similar to that of pretreatment with water or ethanol. However, the effect of Azone on the skin permeation of inorganic ions was relatively low, whereas that of pretreatment with water or ethanol was high.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
32.
Effects of mesenteric nerve stimulation on the electrical activity of myenteric neurons in the guinea pig ileum 总被引:1,自引:0,他引:1
Effects of mesenteric nerve stimulation on the electrical activity of 28 myenteric neurons were investigated in the myenteric flaps innervated with mesenteric nerves. Mesenteric nerve stimulation evoked slow excitatory postsynaptic potentials (EPSPs), whose amplitude and duration were 24.5 +/- 5.5 mV and 374.6 +/- 58.9 s in 7 AH/Type 2 neurons, respectively. Such slow EPSPs mimic the slow depolarizing action induced by exogenous substance P. It is, therefore, likely that slow EPSPs might be in part mediated by the release of substance P. 相似文献
33.
Yoshiyuki Kaneko Tomohiro Nakayama Kosuke Saito Akihiko Morita Ichiro Sato Aya Maruyama Masayoshi Soma Teruyuki Takahashi Naoyuki Sato 《Hypertension research》2006,29(9):665-671
The risk of cerebral infarction (CI) in an individual is dependent on the interplay between genetic risk factors and environmental influences. Binding of thromboxane A2 (TXA2) to its receptor (TP) modulates thrombosis/hemostasis and plays a significant role in the pathogenesis of CI. The aim of the present study was to investigate the relationship between human TP gene single nucleotide polymorphisms (SNPs) and haplotypes and CI in a Japanese population. A genetic association study was performed in 194 CI patients and 365 non-CI subjects by specifically characterizing 6 SNPs in the human TP gene (rs2271875, rs768963, rs2238634, rs11085026, rs4523 and rs4806942). Analysis demonstrated that there were significant differences in the overall distribution of genotypes and dominant or recessive models of rs2271875 and rs768963 between the CI and the non-CI groups. Multiple logistic regression analysis revealed that the C allele of rs768963 was significantly associated with CI (p = 0.029), even after adjusting for confounding factors (odds ratio: 2.41). Further, the C-T-C haplotype of rs768963-rs2238634-rs4806942 was significantly more frequent in the CI group (23.0%) than in the non-CI group (17.7%). These results suggest that specific SNPs and haplotypes may have utility as genetic markers for the risk of CI and that TP or a neighboring gene is associated with the increased susceptibility to CI. 相似文献
34.
K Chijiiwa R Kiyosawa F Nakayama 《Clinica chimica acta; international journal of clinical chemistry》1988,178(2):181-191
Nucleation time (Cholesterol monohydrate crystallization) in bile has been introduced to distinguish patients with cholesterol gallstone from normal human beings. To test the hypothesis that cholesterol monomer activity correlates with nucleation time, we have examined the relationship between nucleation time, apparent cholesterol monomer activity and cholesterol monomer concentration in the aqueous phase using model biles containing bile salt, phospholipid and cholesterol. Apparent cholesterol monomer activity was inversely well correlated with nucleation time in the dilution study (r = -0.98) and in the cholesterol saturation study (r = -0.88) but positively with cholesterol monomer concentration in the aqueous phase in the dilution study (r = 0.72) and in the cholesterol saturation study (r = 0.93). The results indicate that cholesterol monomer activity reflects the nucleation time in model bile system. 相似文献
35.
Autopsy findings from a child with interstitial deletion 6q [46,XX,del(6)(q13q21)] are reported. There was cervical scoliosis, an endocardial cushion defect, right ventricular hypertrophy, subependymal cysts, multicystic kidneys (Potter type IIB), and lung hypoplasia. 相似文献
36.
Masahiro Tsuboi Hisao Asamura Tsuguo Naruke Haruhiko Nakayama Haruhiko Kondo Ryosuke Tsuchiya 《Surgery today》1997,27(11):1074-1076
A video-assisted right upper lobectomy was successfully performed on a 58-year-old man with an anomalnous segmental pulmonary
vein. The tumor was a peripherally located adenocarcinoma. The anomalous vein behind the right main bronchus was identified
and safely divided. This case emphasized that to perform this procedure successfully, (1) a careful preoperative evaluation
of the anatomy, including the presence of any possible vascular and/or bronchial anomalies, is necessary, and (2) if any anatomical
structures cannot be determined intraoperatively, a conversion into an open procedure must immediately be undertaken. 相似文献
37.
Morito Nakayama MD Naoyuki Kataoka MD Yutaka Usui MD Naohiko Inase MD Shigemitsu Takayama MD Hirotaro Miura MD 《The Journal of emergency medicine》1992,10(6):729-734
When nasotracheal intubation with a fiberoptic bronchoscope is performed, the tube may be blocked in the nasal cavity or larynx, resulting in several complications including epistaxis and hoarseness. We review the causes and complications of tube blockage and discuss optimal techniques for minimizing it. 相似文献
38.
Journal of Neurology - An evidence-based approach to the development of clinical practice guidelines has attracted significant attention from physicians' groups as well as from the public.... 相似文献
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