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931.
Synergistic induction of apoptosis by acyclic retinoid and interferon-beta in human hepatocellular carcinoma cells 总被引:5,自引:0,他引:5
Obora A Shiratori Y Okuno M Adachi S Takano Y Matsushima-Nishiwaki R Yasuda I Yamada Y Akita K Sano T Shimada J Kojima S Okano Y Friedman SL Moriwaki H 《Hepatology (Baltimore, Md.)》2002,36(5):1115-1124
Acyclic retinoid, a synthetic retinoid analog, as well as interferon alfa (IFN-alpha) and IFN-beta induce apoptosis in hepatocellular carcinoma (HCC) cells and are used clinically in the prevention of HCC. Here, we show that acyclic retinoid acts synergistically with IFNs in suppressing the growth and inducing apoptosis (as characterized by DNA fragmentation and chromatin condensation) in 5 human HCC cell lines (JHH7, HuH7, PLC/PRF/5, HLE, and HLF). This synergism was only observed when cells were pretreated with the acyclic retinoid, whereas natural retinoic acids (all-trans and 9-cis retinoic acid) were ineffective. This promotion may be due to up-regulation of type 1 IFN receptor (IFNR) expression by the retinoid. Accordingly, incubation with antitype 1 IFNR antibody abolished the synergy. Enhanced IFNR expression was accompanied by increased expression and DNA-binding activity of STAT1, an intracellular signal transducing molecule of IFNR, and increased induction of 2', 5'-oligoadenyl-5'-triphosphate synthetase, which is a target gene of STAT1. Acyclic retinoid did not have any effects on the growth of normal human hepatocytes (Hc) probably because of a lack of IFNR and STAT1 up-regulation. In conclusion, these results provide a rationale for combined biochemoprevention of HCC using acyclic retinoid and IFN-beta. 相似文献
932.
933.
Kikuchi S Hayashi Y Fujioka S Kukita H Ochi N 《Nihon Ronen Igakkai zasshi. Japanese journal of geriatrics》2002,39(1):88-93
A 68-year-old woman with idiopathic thrombocytopenic purpura (ITP) was admitted to our hospital with acute myocardial infarction on 7 February 1999. She had been treated since 1991 for mitral stenosis and regurgitation, atrial fibrillation due to mitralism, diabetes mellitus, hypertension, hyperlipidemia. Chest radiograph on admission showed cardiomegaly with congestion and cardiothoracic ratio was 63%. The platelet count on admission was 22,000/microliter, but she did not have petechia or purpura. Urgent coronary angiography revealed total occlusion in segment 7, and 13 and 75% stenosis in segment 4PD, 9 and 10. Subsequently, direct percutaneous transluminal coronary angioplasty (PTCA) was performed in segment 7. Dissection occurred during the intervention, and a coronary stent was implanted, we started heparin infusion and medication with ticlopidine hydrochloride as post-stenting therapy after the intervention, and there was no bleeding tendency. 相似文献
934.
Nomura K Miyagawa S Ayukawa K Soeda J Taniguchi S Kawasaki S 《Journal of hepatology》2002,36(5):637-644
935.
936.
937.
Honda N Machida K Hosono M Matsumoto T Matsuda H Oshima M Koizumi K Kosuda S Momose T Mori Y Hashimoto J Shimizu Y 《Radiation Medicine》2002,20(6):281-289
Brain perfusion SPECT (BP-SPECT) has characteristic patterns of abnormality, enabling the differential diagnosis of dementia. The purpose of this study was to measure interobserver variations in the diagnosis of dementia using BP-SPECT. BP-SPECT images of 57 cases, 19 of Alzheimer's disease (AD), eight of multi-infarct dementia (MID), three of Pick's disease, five of other dementias, and 22 normal controls, were interpreted by ten nuclear medicine physicians with varying levels of experience. Brain MR images of the cases were then interpreted apart from SPECT. The physicians independently rated all of the diagnoses listed beforehand according to a five-point scale, with clinical information provided. Receiver-operating characteristic (ROC) curves and the area under the ROC curve (Az) were calculated. Az varied from 0.48 to 0.87. Mean Az's were significantly larger (p<0.05) in the diagnosis by SPECT than in that by MRI (0.715 and 0.629 for dementia vs. normal, 0.670 and 0.560 for AD or MID vs. normal, 0.610 and 0.416 for AD vs. normal, and 0.672 and 0.412 for AD vs. MID, respectively). Considerable interobserver variation was present in BP-SPECT interpretation. BP-SPECT may be more effective for the evaluation of dementia than MRI when the same nuclear medicine physicians interpret both images. 相似文献
938.
Higo N Oishi T Yamashita A Matsuda K Hayashi M 《Cerebral cortex (New York, N.Y. : 1991)》2002,12(5):552-564
Myristoylated alanine-rich C-kinase substrate (MARCKS) is a major substrate for protein kinase C, and is involved in synaptic plasticity. Using both Northern blot and in situ hybridization techniques, we investigated whether MARCKS expression varied according to the cerebral region, including the hippocampal formation, or according to the type of neuron. Northern blot analysis showed that the MARCKS mRNA level was higher in the association areas than in the primary sensory and motor areas of the cerebral neocortex. MARCKS mRNA levels in the hippocampus and the amygdala were as high as those in the association areas. The in situ hybridization experiments confirmed the Northern blot results and showed the distribution and characteristics of MARCKS mRNA-positive neurons. In the association areas of the neocortex, prominent signals were observed in neurons in layers II-VI. In the primary areas, prominent signals were restricted to neurons in layers IV-VI. In the hippocampus, the most intense hybridization signals were observed in neurons in the granule cell layer of the dentate gyrus. The observed region-specific expression might reflect functional specialization for plasticity in individual regions of the monkey cerebral cortex. 相似文献
939.
940.
Norepinephrine‐induced diastolic dysfunction with aortic valve opening under calcium‐loading in rats
Noboru Kaneko Ryuko Matsuda Takahide Nakajima Makoto Shinozaki Naoyuki Ohtani Kazuhiko Oda Hisashi Hasumi Ken Shimamoto 《Drug development research》2006,67(6):511-518
Heart failure associated with a high plasma level of norepinephrine (NE) has an extremely poor prognosis with NE being the most powerful predictor of all‐cause mortality. An increase in the diastolic intracellular calcium level (Ca2+) occurs in left ventricular dysfunction; however, the cause‐and‐effect relationships among Ca2+loading, high plasma NE, and an increase in diastolic ventricular pressure is unclear. Here, we examined the relationship between diastolic dysfunction and NE with and without Ca2+loading in rats. Animals were studied in four groups: Ca2+loading for 45 min (Ca2+group), NE alone for 25 min (30 µg/kg/min NE for 25 min; NE group), Ca2+loading and NE for 25 min after Ca2+loading (Ca2+‐NE group), and a vehicle group. Hemodynamics were examined using a micromanometer‐tipped pressure catheter, and diastolic function was studied using Doppler echocardiography. Significantly increased left ventricular end‐diastolic pressure (LVEDP) and decreased E and Ea waves and deceleration time (DCT) were found in the Ca2+‐NE group, compared with the Ca2+and NE groups. There were no changes in left ventricular pressure (LVP) and LV ejection fraction (EF) among the four groups. NE‐induced diastolic contracture (NEIDC) with aortic valve opening occurred in the diastole when LVP overshot the aortic pressure after co‐administration of NE and Ca2+after Ca2+loading, and pulmonary hemorrhage was observed in all animals of the Ca2+‐NE group. The results support the suggestion that NE may be an important factor in the development of diastolic dysfunction in ischemic heart disease. Drug Dev. Res. 67:511–518, 2006. © 2006 Wiley‐Liss, Inc. 相似文献