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101.
《医学理论与实践》2019,(12)
目的:探讨E_2、P、β-hCG、IL-18、PDCD-5在稽留流产患者血清和绒毛组织的表达及其预警意义。方法:选取2018年1—6月我院收治稽留流产妇女30例作为实验组,同期就诊正常早孕妇女(要求终止妊娠)30例为对照组,测定患者血清和绒毛组织E_2、P、β-hCG、IL-18、PDCD-5表达水平,通过统计学软件分析这些指标与孕妇发生稽留流产的相关性。结果:与对照组相比,实验组受试者血清、绒毛组织中E_2、P和β-hCG水平明显较低(P<0. 05),IL-18和PDCD-5水平明显较高(P<0. 05)。Logistic多元回归分析结果显示,血清E_2、P、β-hCG低表达以及IL-18、PDCD-5高表达为孕妇发生稽留流产的危险因素(P<0. 05)。结论:血清、绒毛组织中E_2、P、β-hCG低表达以及IL-18、PDCD-5高表达与孕妇稽留流产发生有关,具有一定预警作用。 相似文献
102.
《Environmental toxicology and pharmacology》2014,37(1):210-219
Infiltration of circulatory inflammatory cells is a common histopathological finding in target organs following cadmium administration, but there is paucity of data concerning their activity. In this study, the effects of sublethal (1 mg/kg) cadmium on peripheral blood polymorphonuclear (PMN) cells were examined 48 h following administration in rats, when tissue (liver and lung) infiltration of these cells was observed. Cadmium administration resulted in systemic inflammatory cytokine and acute phase response with an increase in circulatory neutrophil numbers and cells that express CD11b molecules. Rise in basic aspects of oxidative activity including intracellular myeloperoxidase (MPO), reactive oxygen (nitroblue tetrazolium/NBT cytochemical assay) and nitrogen (Griess assay) species production was observed in PMNs from cadmium-administered rats. A decrease in levels of mRNA for IL-1β, TNF-α and IL-6 was noted, but production of these cytokines was affected differentially. Described effects of cadmium on PMNs add further to the understanding of inflammatory potential of this environmental contaminant. 相似文献
103.
《Drug metabolism reviews》2012,44(1-2):89-116
Dehydroepiandrosterone has been thought to have physiological functions other than as an androgen precursor. The previous studies performed have demonstrated a number of biological effects in rodents, such as amelioration of disease in diabetic, chemical carcinogenesis, and obesity models. To date, activation of the peroxisome proliferators activated receptor alpha, pregnane X receptor, and estrogen receptor by DHEA and its metabolites have been demonstrated. Several membrane-associated receptors have also been elucidated leading to additional mechanisms by which DHEA may exert its biological effects. This review will provide an overview of the receptor multiplicity involved in the biological activity of this sterol. 相似文献
104.
《Growth factors (Chur, Switzerland)》2013,31(4):298-308
AbstractBrain-derived neurotrophic factor (BDNF) promotes neuronal survival through TrkB-FL activation. The activation of adenosine A2A receptors (A2AR) is essential for most of BDNF-mediated synaptic actions, such as synaptic plasticity, transmission and neurotransmitter release. We now aimed at evaluating the A2AR influence upon BDNF-mediated neuroprotection against Aβ25–35 toxicity in cultured neurons. Results showed that BDNF increases cell survival and reduces the caspase-3 and calpain activation induced by amyloid-β (Aβ) peptide, in a mechanism probably dependent on PLCγ pathway. This BDNF-mediated neuroprotection is not affected by A2AR activation or inhibition. Moreover neither activation nor inhibition of A2AR, per se, significantly influenced Aβ-induced neuronal death on calpain-mediated cleavage of TrkB induced by Aβ. In conclusion, these results suggest that, in opposition to the fast synaptic actions of BDNF, the neuroprotective actions of this neurotrophin against a strong Aβ insult do not require the activation of A2AR. 相似文献
105.
ObjectivesGrowth factors play a significant role in cell proliferation and differentiation during different stages of the bone repair. However, several limitations have been brought researchers attention to an osteoinductive small molecule including Purmorphamine. In this study, we aimed to evaluate the effect of Purmorphamine on adhesion, proliferation and differentiation of human dental pulp stem cells (hDPSCs) seaded on beta-tricalcium phosphate (β-TCP) granules.MethodshDPSCs were established from extracted wisdom teeth of healthy volenteers. Cells at passage 3 were seeded on β-TCP in the presence or absence of Purmorphamine. Cell adhesion and proliferation were assessed using scanning electeron microscopy (SEM) and DNA counting assay, respectively, after 1, 3 and 5 days. Then, hDPSCs seeded on β-TCP were subjected to osteogenic medium with or without Purmorphamine. After 7 and 14 days osteogenic diffrentiation capability of hDPSCs were determined using real-time RT-PCR and alkaline phosphatase (ALP) activity assay.ResultsThe significant increase in amount of DNA was observed at day 3 and 5 in the presence of Purmorphamine. SEM imaging also was confirmed the DNA counting assay; in all given time points, hDPSC attachment and growth was significantly higher in the presence of Purmorphamine. ALP activity was increased by Purmorphamine at both 7 and 14 days of induction. Purmorphamine showed to effect on osteopontin expression at earlier stage of osteogenic differentiation, whereas for osteocalcin expression, this effect was more evident at later stage of differentiation.ConclusionPurmorphamine had a promotive effect on adhesion, proliferation and osteogenic differentiation of hDPSCs cultured on β-TCP. The outcome of the current study would help in development of in vitro culture conditions for better osteogenic differentiation of hDPSCs prior to transplantation. 相似文献
106.
107.
Nur Aziah Hanapi Ahmad Saifuddin Mohamad Arshad Jafri Malin Abdullah Tengku Sifzizul Tengku Muhammad Siti R. Yusof 《Journal of pharmaceutical sciences》2021,110(2):698-706
Neurotherapeutic potentials of Centella asiatica and its reputation to boost memory, prevent cognitive deficits and improve brain functions are widely acknowledged. The plant's bioactive compounds, i.e. asiaticoside, madecassoside and asiatic acid were reported to have central nervous system (CNS) actions, particularly in protecting the brain against neurodegenerative disorders. Hence, it is important for these compounds to cross the blood-brain barrier (BBB) to be clinically effective therapeutics. This study aimed to explore the capability of asiaticoside, madecassoside and asiatic acid to cross the BBB using in vitro BBB model from primary porcine brain endothelial cells (PBECs). Our findings showed that asiaticoside, madecassoside and asiatic acid are highly BBB permeable with apparent permeability (Papp) of 70.61 ± 6.60, 53.31 ± 12.55 and 50.94 ± 10.91 × 10?6 cm/s respectively. No evidence of cytotoxicity and tight junction disruption of the PBECs were observed in the presence of these compounds. Asiatic acid showed cytoprotective effect towards the PBECs against oxidative stress. This study reported for the first time that Centella asiatica compounds demonstrated high capability to cross the BBB, comparable to central nervous system drugs, and therefore warrant further development as therapeutics for the treatment of neurodegenerative diseases. 相似文献
108.
Response surface methodology was employed to study the effects of Maillard reaction conditions on the antigenicity of β-lactoglobulin (β-LG) in whey protein isolate (WPI) and to optimise the Maillard reaction conditions of WPI conjugate with oligoisomaltose under which the antigenicity of β-LG reduced to the minimum value. The antigenicity of β-LG and α-lactalbumin (α-LA) in natural and glycated WPI during simulated gastric digestion were investigated. The antigenicity of β-LG was reduced from 272.4 µg mL?1 to 30.99 µg mL?1 under the optimal Maillard reaction conditions. After 120 min simulated gastric digestion, the antigenicity of β-LG in natural and glycated WPI were 42.83 µg mL?1 and 15.66 µg mL?1, respectively. And the antigenicity of α-LA in natural and glycated WPI were 0.78 µg mL?1 and 0.03 µg mL?1, respectively. 相似文献
109.
转化生长因子-β(TGF-β)是一种多功能的细胞因子,在眼科疾病的发生、发展以及转归中都具有重要的作用。本文就近年来国内外有关TGF-β在眼科的研究近况及研究进展进行综述。 相似文献
110.
《Expert opinion on investigational drugs》2013,22(8):1147-1168
Several epidemiological studies suggest that long-term use of non-steroidal anti-inflammatory drugs (NSAIDs) may protect against Alzheimer's disease (AD), especially for patients carrying one or more ?4 allele of the apolipoprotein E. The biological mechanism of this protection is not completely understood and may involve inhibition of COX activity, inhibition of β-amyloid1-42 (Aβ42) production and aggregation, inhibition of β-secretase activity, activation of PPAR-γ or stimulation of neurotrophin synthesis. Unfortunately, long-term, placebo-controlled clinical trials with both non-selective and COX-2 selective NSAIDs in AD patients produced negative results. A secondary prevention study with rofecoxib in patients with mild cognitive impairment and a primary prevention study with naproxen and celecoxib in elderly subjects with a family history of AD were also negative. All these failures have diminished the hope that NSAIDs could be beneficial in the treatment of AD. It is hypothesized that the chronic use of NSAIDs may be beneficial only in the normal brain by inhibiting the production of Aβ42. Once the Aβ deposition process has started, NSAIDs are no longer effective and may even be detrimental because of their inhibiting activity on activated microglia of the AD brain, which mediates Aβ clearance and activates compensatory hippocampal neurogenesis. 相似文献