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91.
Seung-Hwan Kwon Shi-Xun Ma Hyun-Joong Joo Seok-Yong Lee Choon-Gon Jang 《Biomolecules & therapeutics.》2013,21(6):462-469
Eucommia ulmoides Oliv. Bark (EUE) is commonly used for the treatment of hypertension, rheumatoid arthritis, lumbago, and ischialgia as well as to promote longevity. In this study, we tested the effects of EUE aqueous extract in graded doses to protect and enhance cognition in scopolamine-induced learning and memory impairments in mice. EUE significantly improved the impairment of short-term or working memory induced by scopolamine in the Y-maze and significantly reversed learning and memory deficits in mice as measured by the passive avoidance and Morris water maze tests. One day after the last trial session of the Morris water maze test (probe trial session), EUE dramatically increased the latency time in the target quadrant in a dose-dependent manner. Furthermore, EUE significantly inhibited acetylcholinesterase (AChE) and thiobarbituric acid reactive substance (TBARS) activities in the hippocampus and frontal cortex in a dose-dependent manner. EUE also markedly increased brain-derived neurotrophic factor (BDNF) and phosphorylation of cAMP element binding protein (CREB) in the hippocampus of scopolamine-induced mice. Based on these findings, we suggest that EUE may be useful for the treatment of cognitive deficits, and that the beneficial effects of EUE are mediated, in part, by cholinergic signaling enhancement and/or protection. 相似文献
92.
93.
Won-Yung Lee Soon-Woo Jang Jin-Seok Lee Yun-Hee Kim Hyeong-Geug Kim Jong-Min Han Dong-Woon Kim Min-Hee Yi Min-Kyung Choi Chang-Gue Son 《Journal of ethnopharmacology》2014
Ethnopharmacological relevance
Uwhangchungsimwon (UCW) is a representative traditional herbal medicine for central nervous system disorders in East Asia countries over thousand years. To evaluate the pharmacological effects of UCW against oxidative brain injury in a chronic restraint stress mice model.Methods and materials
C57BL/6 male mice underwent daily oral administration of distilled water, UCW or ascorbic acid 1 h before induction of restraint stress (5 h of immobilization daily for 14 days). Nitric oxide (NO), total reactive oxygen species (ROS) levels, malondialdehyde, protein carbonyl contents, and activities of antioxidant enzymes, and concentrations of corticosterone, adrenaline, noradrenaline, and dopamine, were measured in brain tissues or sera.Results
Restraint stress notably increased NO and ROS levels, malondialdehyde and protein carbonyl contents in brain tissues, but decreased activities of catalase, glutathione reductase and glutathione peroxidase. These alterations were significantly ameliorated by UCW. UCW significantly attenuated the elevated serum concentrations of corticosterone, adrenaline and noradrenaline. UCW also significantly normalized the gene expressions in brain tissues altered by restraint stress; up-regulation of phenylethanolamine N-methyltransferase (PNMT) and N-methyl-d-aspartate type 1 receptor (NMDAR1), and down-regulation of gamma-Aminobutyric acid type A receptor (GABAAR), glutamate decarboxylase 1 (GAD 67), and glutamate decarboxylase 2 (GAD 65), respectively. Moreover, UCW considerably restored neurogenesis in the hippocampal regions which was disturbed by chronic restraint stress.Conclusions
These results evidenced that UCW has pharmacological properties for brain protection and neurogenesis in status of stress-associated oxidative damage, and the underlying mechanisms involve the regulation of HPA axis in stress responses. 相似文献94.
Ha Neui Kim Yu Ri Kim Ji Yeon Jang Young Whan Choi Jin Ung Baek Jin Woo Hong Yung Hyun Choi Hwa Kyoung Shin Byung Tae Choi 《Journal of ethnopharmacology》2013
Ethnopharmacological relevance
Dried roots of Polygonum multiflorum have traditionally been used in the retarding of aging process in East Asian countries and its extracts exhibit anti-oxidative activities.Materials and methods
Neuroprotective effects of ethyl acetate extract from Polygonum multiflorum (EEPM) were investigated against glutamate-induced oxidative cell death in HT22 hippocampal cells. Cell viability, cytotoxicity, morphological, flow cytometry, and Western blot assays were performed in order to observe alterations of neuronal cell survival or death related pathways.Results
Pretreatment with EEPM resulted in significantly decreased glutamate-induced neurotoxicity and also resulted in drastically inhibited glutamate-induced apoptotic and necrotic neuronal death. To elucidate possible pathways of neuroprotection by EEPM, we explored the activation of mitogen activated protein kinases (MAPKs), phosphatidylinositol-3-kinase, and cAMP responsive element binding protein (CREB). Treatment with glutamate alone led to activation of extracellular regulated kinase (ERK), Jun N-terminal kinase, and p38 during the late phase after glutamate exposure, but pretreatment with EEPM resulted in significantly attenuated activation of these proteins. Pretreatment with EEPM resulted in increased activation of CREB. The specific inhibitors of ERK and p38, PD98059 and SB203580, abrogated the neuroprotective effects of EEPM. When we evaluated calpain I and striatal-enriched protein tyrosine phosphatase (STEP), active form of calpain I was significantly increased after glutamate exposure, and, along with this, active form of STEP showed a decrease. Pretreatment with EEPM resulted in significant recovery of pro-calpain I and active form of STEP caused by glutamate. Co-treatment with calpain inhibitor ALLN and EEPM had a synergistic effect on neuronal death and contributed to blockade of activation of both ERK and p38 with increased activation of CREB.Conclusions
These results suggest that Polygonum multiflorum extract may have neuroprotective effects through both alleviation of ERK and p38 activation with increased activation of CREB under oxidative stress and has potential as a therapeutic intervention for treatment of oxidative neuronal death. 相似文献95.
Jun-Pil Jang Gil Soo Kim Tae Hoon Oh Beomcheol Park Minhee Kim Gwi Ja Hwang Hyeok-Won Lee Jin-Gyeom Lee Young-Soo Hong Jong Seog Ahn Sung-Kyun Ko Jae-Hyuk Jang 《RSC advances》2022,12(35):22360
Two new polyketide glycosides jejuketomycins A (1) and B (2), were isolated from a culture of Streptomyces sp. KCB15JA151. Their chemical structures including the absolute configurations were determined by detailed analyses of the NMR and HRMS data and ECD calculations and spectral data. Compounds 1 and 2 possess an unusual 6/6/8 tricyclic ring system. Biological evaluation with the wound healing assay and time-lapse cell tracking analysis revealed that compounds 1 and 2 have significant inhibitory activities against cancer cell migration with low cytotoxicity.Two new polyketide glycosides jejuketomycins A (1) and B (2), were isolated from a culture of Streptomyces sp. KCB15JA151. 相似文献
96.
Yasuo Yanagi Aya Iriyama Woo-Dong Jang Kazuaki Kadonosono 《Albrecht von Graefes Archiv fur klinische und experimentelle Ophthalmologie》2007,245(5):677-681
Background The purpose of the study was to investigate the brightness of the xenon/bandpass light in vitrectomy and assess its phototoxic
effects using A2E-laden retinal pigment epithelial (RPE) cells.
Methods The total luminous flux and spectral irradiance of 20- and 25-gauge endoilluminators connected to xenon lamps were measured
and compared to those of 20- and 25-gauge endoilluminators connected to a halogen lamp. In vitro, A2E-laden cells were evenly
exposed to xenon/bandpass light for 5 to 30 min positioned at 1 cm and 2 cm for a standard light probe and an implantable
“chandelier” light probe, respectively, above the cells, and the cell viability was assessed using WST-1 assay. The cell viability
was compared with cells exposed to 30 min of halogen light projected through a 20-gauge endoilluminator.
Results The maximal total luminous flux of xenon/bandpass light emitted through the 20-gauge endoilluminator was 2.8 times higher
than that of the halogen light. The total luminous flux of the 25-gauge endoilluminators was 0.6-1.1 times greater than the
20-gauge endoilluminators connected to the halogen light. The viability of the A2E-laden cells after exposure to the xenon/bandpass
light was no different than that of the cells exposed to the halogen light when the total luminous flux of these lights was
at the same level. Xenon/bandpass light from an implantable “chandelier” light probe induced A2E-mediated RPE damage to a
similar extent as that of the halogen light through a 20-gauge endoilluminator.
Conclusions A2E-mediated phototoxicity of xenon/bandpass light is comparable to that of halogen light. 相似文献
97.
Effects of heme oxygenase system on the cyclooxygenase in the primary cultured hypothalamic cells 总被引:3,自引:0,他引:3
Hae-Uk Lee Hee-Joo Lee Ha-Young Park Sang-Ho Lee Choon-Gon Jang Seok-Yong Lee 《Archives of pharmacal research》2001,24(6):607-612
Endogenous carbon monoxide (CO) shares with nitric oxide (NO) a role as a putative neural messenger in the brain. Both gases are believed to modulate CNS function via an increase in cytoplasmic cGMP concentrations secondary to the activation of soluble guanylate cyclase (sGC). Recently CO and NO were proposed as a possible mediator of febrile response in hypothalamus. NO has been reported to activate both the constitutive and inducible isoform of the cyclooxygenase (COX). Thus, we investigated whether CO arising from heme catabolism by heme oxygenase (HO) is involved in the febrile response via the activation of COX in the hypothalamus. PGE2 which is a final mediator of febrile response released from primary cultured hypothalamic cells was taken as a marker of COX activity. PGE2 concentration was measured with EIA kits. Exogenous CO (CO-saturated medium) and hemin (a substrate and potent inducer of HO) evoked an increase in PGE2 release from hypothalamic cells, and these effects were blocked by methylene blue (an inhibitor of sGC). And membrane permeable cGMP analogue, dibutyryl-cGMP elicited significant increases in PGE2 release. These results suggest that there may be a functional link between HO and COX enzymatic activities. The gaseous product of hemin through the HO pathway, CO, might play a role through the modulation of the COX activity in the hypothalamus. 相似文献
98.
Comparative toxicity of silicon dioxide,silver and iron oxide nanoparticles after repeated oral administration to rats 下载免费PDF全文
Jun‐Won Yun Seung‐Hyun Kim Ji‐Ran You Woo Ho Kim Ja‐June Jang Seung‐Kee Min Hee Chan Kim Doo Hyun Chung Jayoung Jeong Byeong‐Cheol Kang Jeong‐Hwan Che 《Journal of applied toxicology : JAT》2015,35(6):681-693
Although silicon dioxide (SiO2), silver (Ag) and iron oxide (Fe2O3) nanoparticles are widely used in diverse applications from food to biomedicine, in vivo toxicities of these nanoparticles exposed via the oral route remain highly controversial. To examine the systemic toxicity of these nanoparticles, well‐dispersed nanoparticles were orally administered to Sprague–Dawley rats daily over a 13‐week period. Based on the results of an acute toxicity and a 14‐day repeated toxicity study, 975.9, 1030.5 and 1000 mg kg–1 were selected as the highest dose of the SiO2, Ag and Fe2O3 nanoparticles, respectively, for the 13‐week repeated oral toxicity study. The SiO2 and Fe2O3 nanoparticles did not induce dose‐related changes in a number of parameters associated with the systemic toxicity up to 975.9 and 1000 mg kg–1, respectively, whereas the Ag nanoparticles resulted in increases in serum alkaline phosphatase and calcium as well as lymphocyte infiltration in liver and kidney, raising the possibility of liver and kidney toxicity induced by the Ag nanoparticles. Compared with the SiO2 and Fe2O3 nanoparticles showing no systemic distribution in all tissues tested, the Ag concentration in sampled blood and organs in the Ag nanoparticle‐treated group significantly increased with a positive and/or dose‐related trend, meaning that the systemic toxicity of the Ag nanoparticles, including liver and kidney toxicity, might be explained by extensive systemic distribution of Ag originating from the Ag nanoparticles. Our current results suggest that further study is required to identify that Ag detected outside the gastrointestinal tract were indeed a nanoparticle form or ionized form. Copyright © 2015 John Wiley & Sons, Ltd. 相似文献
99.
Yoonjung Jang Won Seok Lee Sei Sai Jeong Yub Kim Jong-Ki Kim Eun Ho Kim 《Oncology Letters》2022,24(4)
Liver cancer is a common malignancy worldwide, with a poor prognosis and a high recurrence rate despite the available treatment methodologies. Tumor-treating fields (TTFields) have shown good preclinical and clinical results for improving the prognosis of patients with glioblastoma and malignant pleural mesothelioma. However, there is minimal evidence for the effect of TTFields on other cancer types. Thus, the present study aimed to investigate the therapeutic efficacy of TTFields in an in vitro model, and to further elucidate the underlying mechanisms. In the present study, two hepatocellular carcinoma (HCC) cell lines (Hep3B and HepG2) were treated with TTFields (intensity, 1.0 V/cm; frequency, 150 kHz) in order to determine the potential antitumor effects of this approach. TTFields significantly inhibited the proliferation and viability of HCC cell lines, as measured using Trypan blue and MTT assays, as well as colony formation in three-dimensional cultures. The TTFields also significantly inhibited the migration and invasion of HCC cells in Transwell chamber and wound-healing assays. Moreover, TTFields enhanced the production of reactive oxygen species in the cells and increased the proportion of apoptotic cells, as evidenced by increased caspase-3 activity, as well as PARP cleavage in western blotting experiments. All of these effects were increased following the application of TTFields in combination with the multi-kinase inhibitor sorafenib, which demonstrated a synergistic effect. Thus, to the best of our knowledge, these results demonstrate for the first time the potential of TTFields in improving the sensitivity of HCC cells to sorafenib, which may lay the foundation for future clinical trials for this combination treatment strategy. 相似文献
100.