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81.
复方甘草甜素治疗严重急性呼吸综合征的疗效   总被引:1,自引:0,他引:1  
目的:探讨复方甘草甜素治疗严重急性呼吸综合征(SARS)的疗效.方法:选102例SARS患者,其中复方甘草甜素治疗27例,谷胱甘肽治疗20例;55例作为对照.观察患者临床症状的改变,治疗前后分别测ALT,AST和TBil值.结果:复方甘草甜素对咳嗽、胸闷、气短及关节痛症状有改善作用.复方甘草甜素治疗组与对照组患者激素最大剂量、激素最大剂量时间、激素减量时间及住院天数的差异均无显著性;复方甘草甜素具有保肝降酶作用,对血常规及电解质无明显影响.结论:复方甘草甜素具有保肝降酶作用,对SARS可能有一定的疗效.  相似文献   
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83.
Naphthalene (NA) is metabolized to highly reactive intermediates that are primarily detoxified by conjugation to glutathione (GSH). Intraperitoneal administration of naphthalene causes substantial loss of both hepatic and respiratory GSH, yet only respiratory tissues are injured in mice. The liver supplies GSH to other organs via the circulation, making it unclear whether respiratory GSH losses reflect in situ respiratory depletion or decreased hepatic supply. To address this concern, mice were exposed to naphthalene by inhalation (1.5-15 ppm; 2-4 h), thereby bypassing first-pass hepatic involvement. GSH levels and histopathology were monitored during the first 24 h after exposure. Half of the mice were given the GSH depletor diethylmaleate (DEM) 1 hour before naphthalene exposure. Lung and nasal GSH levels rapidly decreased (50-90%) in mice exposed to 15 ppm naphthalene, with cell necrosis throughout the respiratory tract becoming evident several hours later. Conversely, 1.5 ppm naphthalene caused moderate GSH loss and only injured the nasal olfactory epithelium. Neither naphthalene concentration depleted hepatic GSH. Animals pretreated with DEM showed significant GSH loss and injury in nasal and intrapulmonary airway epithelium at both naphthalene concentrations. DEM treatment, perhaps by causing significant GSH loss, decreased water-soluble naphthalene metabolite formation by 48% yet increased NA-protein adducts 193%. We conclude that (1) GSH depletion occurs in airways independent of hepatic function; (2) sufficient GSH is not supplied by the liver to maintain respiratory GSH pools, or to prevent injury from inhaled naphthalene; and (3) GSH loss precedes injury and increases protein adduct formation.  相似文献   
84.
谷胱甘肽-S-转移酶M1基因多态与食管癌的Meta分析   总被引:1,自引:0,他引:1       下载免费PDF全文
目的 对谷胱甘肽-S-转移酶M1(GSTM1)基因多态与食管癌的关联性进行Meta分析。方法 以食管癌组与对照组人群基因型分布的OR值为效应指标,各资料间进行一致性检验,以确定采用固定或随机效应模型进行合并分析。发表偏倚评估用漏斗图法进行。结果 共收集国内外相关资料11篇,积累病例1190例,对照1964名,合并OR值为1.197(95%CI:0.846~1.692)。对其中5篇资料按吸烟与否分层,吸烟组合并OR值为1.523(95%CI:1.099~2.109);不吸烟组合并OR值为0.933(95%CI:0.469~1.692)。结论 GSTM1基因多态与食管癌的易感性无关,但携带GSTM1空白基因型的吸烟者患食管癌的危险性可能会增加。  相似文献   
85.
Polycystic ovary syndrome (PCOS)is a gynecological endocrine disorder which is associated with systemic inflammatory status inducing red blood cells (RBC) membrane alterations related to insulin resistance and testosterone levels which could be greatly improved by myo-inositol (MYO) uptake. In this study we aim to evaluate the effect of MYO in reducing oxidative-related alterations through in vitro study on PCOS RBC. Blood samples from two groups of volunteers, control group (CG, n?=?12) and PCOS patient group (PG, n?=?12), were analyzed for band 3 tyrosine phosphorylation (Tyr-P), high molecular weight aggregate (HMWA), IgG in RBC membranes, and glutathione (GSH) in cytosol, following O/N incubation in the presence or absence of MYO. PCOS RBC underwent oxidative stress as indicated by higher band 3 Tyr-P and HMWA and increased membrane bound autologous IgG. Twenty four hours (but not shorter time) MYO incubation, significantly improved both Tyr-P level and HMWA formation and concomitant membrane IgG binding. However, no relevant modification of GSH content was detected. PCOS RBC membranes are characterized by increased oxidized level and enhanced sensitivity to oxidative injuries leading to potential premature RBC removal. MYO treatment is effective in reducing oxidative related abnormalities in PCOS patients probably restoring the inositol phospholipid pools of the membranes.  相似文献   
86.
280 male foetuses aged 4–10 lunar months were obtained from therapeutic abortions. Growth of the craniofacial skeleton was determined from measurement of sagittal radiographs. Univariate and multivariate analysis of the data showed considerable size changes during the foetal period but relatively little change in overall shape.  相似文献   
87.
Detoxication enzymes play an important role in insect resistance to xenobiotics such as insecticides and phytochemicals. We studied the pathway for activating the expression of glutathione S‐transferases (GSTs) in response to selected xenobiotics. An assay of the promoter activity of GST epsilon 1 (Slgste1) of Spodoptera litura led to the discovery of a cis‐regulating element. An antioxidant response element was activated in response to indole‐3‐carbinol (I3C) and chlorpyrifos (CPF) and was able to bind with the xenobiotic sensor protein nuclear factor erythroid‐derived 2–related factor 2 (SlNrf2). SlNrf2 and Slgste1 were responsive to reactive oxygen species induced by I3C and CPF in a S. litura cell line, as well as in S. litura midguts. SlNrf2 RNA interference (RNAi) reduced the message RNA levels of Slgste1 and the peroxidase activity of GSTs in response to I3C, xanthotoxin, CPF and deltamethrin. SlNrf2 RNAi and inhibitor treatment of GST activity decreased the viability of I3C‐treated cells. These results indicate that SlNrf2 activates the expression of GSTs in response to oxidative stresses caused by exposure to xenobiotics.  相似文献   
88.
To assess the status of oxidative stress in benign prostate hyperplasia, a very common disease in older men which constitutes a public health problem in Jijel, prostate tissues were obtained by transvesical adenomectomy from 10 men with benign prostate hyperplasia. We measured the cytosolic levels of malondialdehyde (MDA) and glutathione (GSH) and cytosolic enzyme activities of superoxide dismutase, catalase, glutathione peroxidase and glutathione S‐transferase. The development of benign prostate hyperplasia is accompanied by impaired oxidative status by increasing levels of MDA, depletion of GSH concentrations and a decrease in the activity of all the antioxidant enzymes studied. These results have allowed us to understand a part of the aetiology of benign prostate hyperplasia related to oxidative stress.  相似文献   
89.
Protocatechuic acid (PCA) at 0.5%, 1% or 2% was supplied to d-galactose (DG) treated mice for 8 week. PCA intake at 2% increased its deposit in brain. DG treatment increased brain level of reactive oxygen species, protein carbonyl, carboxymethyllysine, pentosidine, sorbitol, fructose and methylglyoxal (P < 0.05). PCA intake, at 1% and 2%, lowered brain level of these parameters (P < 0.05). DG treatments enhanced activity and protein expression of aldose reductase (AR) and sorbitol dehydrogenase, as well as declined glyoxalase I (GLI) activity and protein expression (P < 0.05). PCA intake at 1% and 2% reduced activity and protein expression of AR (P < 0.05), and at 2% restored GLI activity and expression (P < 0.05). DG injection also elevated cyclooxygenase (COX)-2 activity and expression, and increased the release of interleukin (IL)-1beta, IL-6, tumor necrosis factor-alpha and prostaglandin E2 in brain (P < 0.05). PCA intake decreased these cytokines (P < 0.05), and at 1% and 2% suppressed COX-2 activity and expression (P < 0.05). PCA intake at 1% and 2% also lowered DG-induced elevation in activity, mRNA expression and protein production of nuclear factor kappa B p65 (P < 0.05). These findings suggest that the supplement of protocatechuic acid might be helpful for the prevention or alleviation of aging.  相似文献   
90.
Abnormal redox homeostasis and oxidative stress have been proposed to play a role in the etiology of several neuropsychiatric spectrum disorders. Emerging interest has recently focused on markers of oxidative stress and neuroinflammation in schizophrenic spectrum disorders, at least in particular subgroups of patients. Altered expression of genes related to oxidative stress, oxidative damage to DNA, protein and lipids, as well as reduced glutathione levels in central and peripheral tissues could act synergistically, and contribute to the course of the disease. Herein, we discuss cellular mechanisms that may be operative in neuroinflammation and contributory to schizophrenia. We address modulation of endogenous cellular defense mechanisms as a potentially innovative approach to therapeutics for schizophrenia, and other neuropsychiatric conditions that are associated with neuroinflammation. Specifically, we discuss the emerging role of heme oxygenase as prominent member of neuroprotective network in redox stress responsive mechanisms, as well as the importance of glutathione relevant in schizophrenia pathophysiology. Finally we introduce the hormetic dose response concept as relevant and important to neuroprotection, and review hormetic mechanisms as possible approaches to manipulation of neuroinflammatory targets that may be viable for treating schizophrenia spectrum disorders. © 2016 Wiley Periodicals, Inc.  相似文献   
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