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981.
Formaldehyde (FA) is an important substance that induces sick house syndrome and diseases, such as asthma and allergies. Oxidative stress is involved in the development of respiratory disease, and diverse antioxidants may protect respiratory tract cells from apoptosis. Peroxiredoxin is a pivotal endogenous antioxidant. In the present study, FA induced death in A549 cells, a lung epithelial cell line, in a dose-dependent manner. FA also increased lipid peroxide formation (LPO) in A549 cells, suggesting a role for oxidative stress. Additionally, FA decreased peroxiredoxin 2 (Prx 2) protein levels after a 24 or 48 h exposure to FA. We also examined whether the FA-induced decrease in Prx 2 was associated with apoptosis. Prx 2 overexpression protected against FA-induced cell apoptosis but not necrosis. Prx 2 overexpression blocked FA-induced increase in Bax, a pro-apoptotic molecule, and a decrease in Bcl-2, an anti-apoptotic molecule. Prx 2 overexpression also protected against FA-induced activation of some special apoptosis-associated proteins [caspase-3, caspase-9, and polypeptide poly (ADP-ribose) polymerase (PARP)]. Furthermore, we examined the signaling molecules involved in the FA-induced decrease in Prx 2 expression. The FA-induced decrease in Prx 2 and increase in cell apoptosis was restored by treatment with SB203580 [a p38 mitogen activated protein kinase (MAPK) inhibitor], but not by SP600125 [a c-jun-N-terminal kinase (JNK) inhibitor]. Also, FA-induced events were blocked by treatment with p38 siRNA, but not by scrambled siRNA. Indeed, FA increased p38 MAPK activation, suggesting a role for p38 MAPK in FA action. In conclusion, FA mediated apoptosis in lung epithelial cells by decreasing Prx 2 via p38 MAPK. 相似文献
982.
Jee Yeon Jeong Sangjun Choi Young Lim Kho Pan Gyi Kim 《Regulatory toxicology and pharmacology : RTP》2010
Occupational exposure limits (OELs) are used as an important tool to protect workers from adverse chemical exposures and its detrimental effects on their health. The Ministry of Labor (MOL) can establish and publish OELs based on the Industrial Safety and Health Act in Korea. The first set of OELs was announced by the MOL in 1986. At that time, it was identical to the Threshold Limit Values of the American Conference of Governmental Industrial Hygienists. Until 2006, none the first OELs except for those of three chemicals (asbestos, benzene, and 2-bromopropane) were updated during the last twenty years. The Hazardous Agents Review Committee established under the MOL selected 126 chemicals from 698 chemicals covered by OELs using several criteria. From 2005 to 2006, the MOL provided research funds for academic institutions and toxicological laboratories to gather the evidence documenting the need to revise the outdated OELs. Finally, the MOL notified the revised OELs for 126 chemicals from 2007 to 2008. The revised OELs of 58 substances from among these chemicals were lowered to equal or less than half the value of the original OELs. This is the most substantial change in the history of OEL revisions in Korea. 相似文献
983.
Bisphenol A (BPA) is known as an estrogen-mimic environmental hormone which has the ability to indirectly stimulate the production of allergic inflammation-related cytokines. Cudrania tricuspidata Bureau (CTB) has been used in Korean folk medicine for a long time. In order to determine the inhibitory effect of a glycoprotein (CTB glycoprotein, 75 kDa) isolated from CTB fruits on the activities of allergic inflammation-related cytokines (TNF-α and IL-6) caused by BPA, we evaluated the activities of protein kinase C (PKC), p38 mitogen-activated protein kinase (p38 MAPK), nuclear factor (NF)-κB, and inflammation-related cytokine (TNF-α and IL-6) in the BPA-induced HMC-1 cells using immunoblot analysis and RT-PCR. The results obtained from this study revealed that CTB glycoprotein (100 μg/ml) inhibits the translocation of PKC from cytosol to the membrane, the phosphorylation of p38 MAPK, the activation of NF-κB, and the expression levels of TNF-α and IL-6. Taken together, the results in this study suggest that CTB glycoprotein inhibits the expression of allergic inflammation-related cytokines (TNF-α and IL-6) by blocking NF-κB and p38 kinase in BPA-induced HMC-1 cells. 相似文献
984.
Min Jung Park Chun Sik Bae Seul Ki Lim Dong Il Kim Jae Cheong Lim Jong Choon Kim Ho Jae Han Jae Hak Moon Kye Yeop Kim Kyung-Chul Yoon Soo Hyun Park 《Archives of pharmacal research》2010,33(1):151-157
A lot of anti-diabetic agents using natural plants have been extensively studied. Ginsenosides are known to be used as a remedy for diabetes in Asian countries and American Societies. Diabetic nephropathy is a major complication of diabetes mellitus. Extracellular matrix in mesangial cells is mainly composed of fibronectin and the increase of fibronectin is a hallmark of diabetic nephropathy. Protopenaxadiol (PPD) is a major component of total ginseng. Thus, we examined the regulatory mechanism of PPD derivatives-induced preventive effect of fibronectin expression in mesangial cells cultivated under diabetic condition. In present study, ginsenoside Rb1 prevented the high glucose-induced increase of fibronectin expression in mesangial cells. Ginsenoside Rb2 and Rg3 also mildly inhibited it. However, ginsenoside Rc and Rd did not prevent the high glucose-induced increase of fibronectin expression in mesangial cells. In addition, ginsenoside Rb1 prevented high glucose-induced phosphorylation of p44/42 mitogen activated protein kinase (MAPK), p38 MAPK, JNK/SAPK, and Akt. These results suggest that ginsenoside Rb1 is the most powerful component of PPD derivatives. In conclusion, ginsenoside Rb1 prevented high glucose-induced increase of fibronectin expression via the inhibition of MAPK-Akt signaling cascade. 相似文献
985.
Assessment of the anti-angiogenic,anti-inflammatory and antinociceptive properties of ethyl vanillin
Hyun-Joo Jung Yun Seon Song Kyunghoon Kim Chang-Jin Lim Eun-Hee Park 《Archives of pharmacal research》2010,33(2):309-316
The present work aimed to assess novel pharmacological properties of ethyl vanillin (EVA) which is used as a flavoring agent for cakes, dessert, confectionary, etc. EVA exhibited an inhibitory activity in the chorioallantoic membrane angiogenesis. Anti-inflammatory activity of EVA was convinced using the two in vivo models, such as vascular permeability and air pouch models in mice. Antinociceptive activity of EVA was assessed using acetic acid-induced writhing model in mice. EVA suppressed production of nitric oxide and induction of inducible nitric oxide synthase in the lipopolysaccharide (LPS)-activated RAW264.7 macrophage cells. However, EVA could not suppress induction of cyclooxygenase-2 in the LPS-activated macrophages. EVA diminished reactive oxygen species level in the LPS-activated macrophages. EVA also suppressed enhanced matrix metalloproteinase-9 gelatinolytic activity in the LPSactivated RAW264.7 macrophage cells. EVA at the used concentrations couldn’t diminish viability of the macrophage cells. Taken together, the anti-angiogenic, anti-inflammatory and anti-nociceptive properties of EVA are based on its suppressive effect on the production of nitric oxide possibly via decreasing the reactive oxygen species level. 相似文献
986.
987.
The clinical manifestation of most diseases of the central nervous system results from neuronal dysfunction or loss. Diseases such as stroke, epilepsy and neurodegeneration (e.g. Alzheimer's disease and Parkinson's disease) share common cellular and molecular mechanisms (e.g. oxidative stress, endoplasmic reticulum stress, mitochondrial dysfunction) that contribute to the loss of neuronal function. Neurotrophic factors (NTFs) are secreted proteins that regulate multiple aspects of neuronal development including neuronal maintenance, survival, axonal growth and synaptic plasticity. These properties of NTFs make them likely candidates for preventing neurodegeneration and promoting neuroregeneration. One approach to delivering NTFs to diseased cells is through viral vector-mediated gene delivery. Viral vectors are now routinely used as tools for studying gene function as well as developing gene-based therapies for a variety of diseases. Currently, many clinical trials using viral vectors in the nervous system are underway or completed, and seven of these trials involve NTFs for neurodegeneration. In this review, we discuss viral vector-mediated gene transfer of NTFs to treat neurodegenerative diseases of the central nervous system. 相似文献
988.
Soo-Hyun Park Yun-Beom Sim Soon-Sung Lim Jin-Kyu Kim Jin-Koo Lee Hong-Won Suh 《The Korean journal of physiology & pharmacology》2010,14(5):285-289
In the present study, the antinociceptive profiles of Campanula punctata extract were examined in ICR mice. The Campanula punctata contain a large dose of saponin. Campanula punctata extract administered orally (200 mg/kg) showed an antinociceptive effect as measured by the tail-flick and hot-plate tests. In addition, Campanula punctata extract attenuated the writhing numbers in the acetic acid-induced writhing test. Furthermore, the cumulative nociceptive response time for intrathecal (i.t.) injection of substance P (0.7 µg) was diminished by Campanula punctata extract. Intraperitoneal (i.p.) pretreatment with yohimbine (α2-adrenergic receptor antagonist) attenuated antinociceptive effect induced by Campanula punctata extract in the writhing test. However, naloxone (opioid receptor antagonist) or methysergide (5-HT serotonergic receptor antagonist) did not affect antinociception induced by Campanula punctata extract in the writhing test. Our results suggest that Campanula punctata extract shows an antinociceptive property in various pain models. Furthermore, this antinociceptive effect of Campanula punctata extract may be mediated by α2-adrenergic receptor, but not opioidergic and serotonergic receptors. 相似文献
989.
Yuri Seo Hyun Taek Lim Byung Joo Lee Jinu Han 《American journal of medical genetics. Part A》2023,191(2):582-585
Spastic paraplegia is a neurodegenerative disorder characterized by progressive leg weakness and spasticity due to degeneration of corticospinal axons. SPG7 encodes paraplegin, and pathogenic variants in the gene cause hereditary spastic paraplegia as an autosomal recessive trait. Various ophthalmological findings including optic atrophy, ophthalmoplegia, or nystagmus have been reported in patients with spastic paraplegia type 7. We report a 15-year-old male patient with a novel heterozygous variant, c.1224T>G:p.(Asp408Glu) in SPG7 (NM_003119.3) causing early onset isolated optic atrophy and infantile nystagmus prior to the onset of neurological symptoms. Therefore, SPG7 should be considered a cause of infantile nystagmus with optic atrophy. 相似文献
990.