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61.
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Introduction

There is evidence to suggest that an association exists between oral infections and coronary heart disease (CHD). Subjects presenting lesions of endodontic origin (LEOs) or pulpal inflammation had an increased risk of developing CHD. However, findings concerning systemic manifestations of apical periodontitis (AP) remain controversial. An association between CD14 gene polymorphisms and atherosclerosis-associated diseases has been shown, but there are no data regarding an association between CD14 polymorphism and AP. This study evaluated associations between clinical oral health status, CD14 polymorphisms, and CHD.

Methods

A case-controlled clinical trial was designed to compare middle-aged adults with acute myocardial infarction or unstable angina (n = 51) within 12 months of the acute event defined as first manifestation with healthy controls (n = 49). Participants were matched for age, sex, and socioeconomic status. Indicators of oral disease and compliance were evaluated. CD14 polymorphisms were analyzed by restriction fragment length polymorphism–polymerase chain reaction.

Results

CHD subjects had a higher prevalence of oral diseases and lower compliance to oral preventive strategies than healthy controls. Multivariate analysis showed a positive association between missing teeth (odds ratio [OR] = 1.37; 95% confidence interval [CI], 1.02–1.85), the number of LEOs (OR = 4.37; 95% CI, 1.69–11.28), chronic periodontitis (OR = 5.87; 95% CI, 1.17–29.4), and CHD. No statistically significant association emerged between the CD14 C(−260)T and the CD14 C(−159)T polymorphism, endodontic or periodontal disease, and CHD.

Conclusions

Chronic oral diseases may increase the risk of CHD and may be an unconventional risk factor for CHD.  相似文献   
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Oral mucositis (OM) and radiodermatitis (RD) are serious side effects of radiotherapy (RT), often leading to its suspension, need for analgesics, and enteral/parenteral nutrition. Laser therapy is becoming a recommended treatment option. This prospective study aimed at demonstrating the beneficial effect of class IV laser therapy (HPLT) on RT-induced OM, an off-label use of HPLT to treat RD in breast cancer patients. Fifty-three cancer patients, during/after RT and/or chemotherapy (CT), affected by OM, were treated with HPLT during four consecutive days (970?±?15 nm, 5 W (50 %), 35–6000 Hz, 240 s). Assessment of OM (Grading Objective Scale, WHO-SCALE), pain (visual analogue scale, VAS), functional ability, subjective parameters, and site/severity of OM were recorded over time. Similarly, 27 breast cancer patients affected by RD were treated by HPLT and monitored over time for grade, discomfort, itching, and bleeding. Progressive improvement of WHO-SCALE from day 7 on, and of VAS from day 2 on (p?<?0.000) was registered. All patients’ functional capacity improved on day 4 (p?<?0.05). All subjective parameters improved on day 14 (p?<?0.001) except for voice, which improved on day 21 (p?<?0.000). Ulcerations’ dimension and erythema’s severity significantly decreased in all sites examined (p?<?0.05). Similarly, HPLT proved to be beneficial in managing RD for all the parameters considered (p?<?0.002). Regardless of OM grade/site and of kind/site of tumor, HPLT proved to be effective in healing OM as well as RD. In both cases, effective treatment can improve life quality through a safe, easy, innovative approach. Therefore, HPLT may become an integral part of everyday practice in the management of RT adverse effects.  相似文献   
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Two-partner secretion (TPS) systems are a family of proteins being rapidly identified and characterized in a growing number of gram-negative bacteria. TPS systems mediate the secretion of proteins, many involved in virulence traits such as hemolysis, adherence to epithelial cells, inhibition of bacterial growth, and immunomodulation of the host. A TPS system typically consists of a transporter located in the bacterial outer membrane (OM) which is responsible for the recognition and secretion of at least one large exoprotein. Two of the better-characterized TPS systems specify the Bordetella pertussis FHA and Haemophilus influenzae HMW1/HMW2 proteins. We identified three gene products of Moraxella catarrhalis strain O35E that resemble TPS proteins and designated them MhaC (transporter), MhaB1 (exoprotein), and MhaB2 (exoprotein). Western blot analysis using anti-MhaC, or antibodies reacting to both MhaB1 and MhaB2 (MhaB-reactive), revealed that these antigens are expressed in the OM of 63% of isolates tested. Mutations in the mhaC gene specifying the putative transporter of the M. catarrhalis wild-type strains O35E, O12E, and McGHS1 resulted in the absence of MhaB1/MhaB2 in the OM of mutants. These results are therefore consistent with the Mha proteins functioning as a TPS system. Furthermore, we discovered that these mhaC mutants exhibit markedly decreased binding to human epithelial cells relevant to pathogenesis by M. catarrhalis (Chang, HEp2, A549, and/or 16HBE14o(-)). Expression of O12E MhaC and MhaB1 in a nonadherent strain of Escherichia coli was found to increase the adherence of recombinant bacteria to HEp2 monolayers by sevenfold, thereby demonstrating that this M. catarrhalis TPS system directly mediates binding to human epithelial cells. The construction of isogenic mutants in the mhaB1 and mhaB2 genes of strain O35E also suggests that the MhaB proteins play distinct roles in M. catarrhalis adherence.  相似文献   
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Much experimental evidence suggests that an imbalance in cellular redox status is a major factor in the pathogenesis of Alzheimer's disease (AD). Our previous data showed a marked increase in membrane lipoperoxidation in primary fibroblasts from familial AD (FAD) patients. In the present study, we demonstrate that when oligomeric structures of Abeta 1-40 and Abeta 1-42 are added to the culture media, they accumulate quicker near the plasma membrane, and are internalized faster and mostly in APPV717I fibroblasts than in age-matched healthy cells; this results in an earlier and sharper increase in the production of reactive oxygen species (ROS). Higher ROS production leads in turn to an increase in membrane oxidative-injury and significant impairment of cellular antioxidant capacity, giving rise to apoptotic cascade activation and finally to a necrotic outcome. In contrast, healthy fibroblasts appear more resistant to amyloid oxidative-attack, possibly as a result of their plasma membrane integrity and powerful antioxidant capacity. Our data are consistent with increasing evidence that prefibrillar aggregates, compared to mature fibrils, are likely the more toxic species of the peptides. These findings provide compelling evidence that cells bearing increased membrane lipoperoxidation are more susceptible to aggregate toxicity as a result of their reduced ability to counteract amyloid oligomeric attack.  相似文献   
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Three species of ectomycorrhizal fungi (Hebeloma crustuliniforme, Suillus variegatus and Cenococcum geophilum) were grown in axenic culture amended with range of AsO4(3-) concentration under three different PO4(3-) regimes. The fungi exhibited different growth responses to AsO4(3-) that varied with PO4(3-) concentration. Suillus variegatus showed the greatest sensitivity to AsO4(3-), with growth almost completely inhibited in the presence of AsO4(3-) under the lower two PO4(3-) treatments. Under the highest PO4(3-) treatment however, growth was enhanced and S. variegatus was able to persist at AsO4(3-) concentrations of up to 4 mM. Hebeloma crustuliniforme also showed high sensitivity to AsO4(3-) especially at low PO4(3-) concentration. The two higher PO4(3-) treatments had an ameliorating effect on AsO4(3-) toxicity in H. crustuliniforme. This demonstrates the ability of PO4(3-) to alleviate AsO4(3-) toxicity. The response from S. variegatus and H. crustuliniforme, both basidiomycetes, was in contrast to the ascomycete C. geophilum. This fungus demonstrated tolerance to AsO4(3-) when grown in culture solution and PO4(3-) did not have an ameliorating effect on AsO4(3-) toxicity in C. geophilum.  相似文献   
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