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991.
Survival and proliferative ability of various living cell types after laser-induced forward transfer 总被引:1,自引:0,他引:1
Hopp B Smausz T Kresz N Barna N Bor Z Kolozsvári L Chrisey DB Szabó A Nógrádi A 《Tissue engineering》2005,11(11-12):1817-1823
The survival, proliferation, and differentiation of freshly isolated and cultured cells were studied after absorbing film-assisted laser-induced forward transfer. Rat Schwann and astroglial cells and pig lens epithelial cells were used for transfer and the cells were cultured for 2 weeks after laser-pulsed transfer. All three cell types survived, proliferated, and differentiated under cell culture conditions and regained their original phenotype a few days after cell transfer. Time resolution studies have shown that the time required to accelerate the jets and droplets containing the cells was less than 1 micros and that the estimated minimum average acceleration of those ejected cells that reached a constant velocity was approximately 10(7) x g. This suggests that the majority of studied cells tolerated the extremely high acceleration at the beginning of the ejection and the deceleration during impact on the acceptor plate without significant damage to the original phenotype. These results suggest that the absorbing film-assisted laser-induced forward transfer technique appears to be suitable for several potential applications in tissue engineering and the biomedical tissue repair technologies. 相似文献
992.
Di Carlo E Cappello P Sorrentino C D'Antuono T Pellicciotta A Giovarelli M Forni G Musiani P Triebel F 《The Journal of pathology》2005,205(1):82-91
The experimentally induced TS/A murine mammary carcinoma is poorly immunogenic and mainly infiltrated by antigen-presenting cells (APCs), namely macrophages and immature dendritic cells (DCs). Human (h) and mouse (m) lymphocyte activation gene-3 (LAG-3 or CD233) is a physiological MHC class II ligand and powerful APC activator. A gene transfer approach has revealed its anti-tumour activity in this model: hLAG-3 was more effective than mLAG-3. To obtain a clearer picture of the immunoregulatory mechanisms associated with the rejection dynamics of h- and m-LAG-3 transfectants, immunohistochemistry and confocal microscopy analyses of TS/A-hLAG-3, TS/A-mLAG-3, and control TS/A-pc tumours were performed. The immune events elicited by mLAG-3 and m-interleukin (IL)-12 were also compared, since their rejection kinetics were quite similar, and LAG-3 enables IL-12 production by macrophages and DCs. Both the TS/A-h- and, to a lesser extent, the m-LAG-3 rejection areas were characterized by an impressive recruitment of APCs, granulocytes, NK cells, CD4+ T lymphocytes and CD8+ IFNgamma-expressing cells. In both cases, infiltration by APCs was accompanied by strong CD80 and CD86 expression and macrophage nitric oxide (NO) synthase up-regulation. Distinct expression of IL-12 and CXCL9 was also found, especially in the draining lymph nodes. T lymphocytes and CD86-expressing APCs were significantly prevalent in both the TS/A-h- and the m-LAG-3 compared with the TS/A-mIL-12 rejection area. Production of IFNgamma, TNFalpha and IL1beta, and chemokines, namely CXCL5, CXCL9, CXCL10, CXCL11, CCL5, and CCL2, by infiltrating leukocytes and signs of defective neovascularization were detected in tumours expressing h-LAG-3-, m-LAG-3-, and m-IL-12. However, IFNgamma, CCL2, and CCL5 production prevailed in the TS/A-hLAG-3 rejection area. Taken together, these results indicate that LAG-3 expression by engineered tumour cells efficiently promotes intra-tumoural recruitment, activation, and Th1 commitment of APCs, and leads to a wide intra-tumoural influx of non-specific and specific reactive cells, and the release of immunoregulatory and cytotoxic mediators. Many of LAG-3's anti-tumour activities are shared with IL-12. 相似文献
993.
994.
Knapen J Van de Vliet P Van Coppenolle H David A Peuskens J Pieters G Knapen K 《Psychotherapy and psychosomatics》2005,74(6):353-361
BACKGROUND: The first objective of this study was to compare the changes in physical self-concept, global self-esteem, depression and anxiety after participation in one of two 16-week psychomotor therapy programs for nonpsychotic psychiatric inpatients. The second objective was to study the relationship between changes in these variables. METHODS: One hundred and ninety-nine inpatients were randomly assigned to either a personalized psychomotor fitness program, consisting of aerobic exercise and weight training, or a general program of psychomotor therapy, consisting of different forms of physical exercises and relaxation training. Physical self-concept was evaluated using the Dutch version of the Physical Self-Perception Profile at baseline, after 8 weeks, and after completion of the 16-week interventions. At the same time points, additional variables of global self-esteem, depression and anxiety were assessed by means of the Rosenberg Self-Esteem Inventory, the Beck Depression Inventory and the Trait Anxiety Inventory, respectively. RESULTS: After 16 weeks, both groups showed significant improvements in all outcome measures (p values ranged from 0.01 to < 0.0001), with no between-group differences. In both groups, the improvement in physical self-concept was correlated with increased global self-esteem and decreased depression and anxiety levels (p < 0.01). CONCLUSIONS: The results suggest that both psychomotor therapy programs are equally effective in enhancing physical self-concept. The relationship between improvements in physical self-concept and enhancements in global self-esteem, depression and anxiety supports the potential role of the physical self-concept in the recovery process of depressed and anxious psychiatric inpatients. 相似文献
995.
von Kries R Toschke AM Strassburger K Kundi M Kalies H Nennstiel U Jorch G Rosenbauer J Giani G 《European journal of pediatrics》2005,164(2):61-69
Deaths in temporal association with vaccination of hexavalent vaccines have been recently reported. The objective of this paper is to assess whether these temporal associations can be attributed to chance. Standardised mortality ratios (SMR) for deaths within 1 to 28 days after administration of either of the two hexavalent vaccines in the 1st and 2nd year of life were determined using the respective annual rates for sudden unexpected deaths (SUDs) from the national vital statistics. The distribution of SUD cases and the vaccination uptake by month were estimated from surveys and sales figures for the individual vaccines. Sensitivity analyses were performed to account for limitations in the data sources. For one of the vaccines, Vaccine B, all SMRs were well below one. For the other, Vaccine A, SMRs exceeded one insignificantly on the 1st day after vaccination in the 1st year of life. In the 2nd year of life, however, the SMRs for SUD cases within 1 day of vaccination with vaccine A were 31.3 (95% CI 3.8–113.1; two cases observed; 0.06 cases expected) and 23.5 (95% CI 4.8–68,6) for within 2 days after vaccination (three cases observed; 0.13 cases expected). Extensive sensitivity analyses could not attribute these findings to limitations of the data sources. Conclusion: These findings based on spontaneous reporting do not prove a causal relationship between vaccination and sudden unexpected deaths. However, they constitute a signal for one of the two hexavalent vaccines which should prompt intensified surveillance for unexpected deaths after vaccination.In this paper the two vaccines have been labelled Vaccine A and Vaccine B. The brand names are not conveyed since the European licensing agency has not recommended regulatory action against either vaccine. 相似文献
996.
Dietary prebiotic oligosaccharides are detectable in the faeces of formula-fed infants 总被引:1,自引:0,他引:1
Moro GE Stahl B Fanaro S Jelinek J Boehm G Coppa GV 《Acta paediatrica (Oslo, Norway : 1992). Supplement》2005,94(449):27-30
Human milk oligosaccharides are not digested during intestinal passage and can be detected in stools. In this study it was investigated whether a prebiotic mixture of low-molecular-weight galacto-oligosaccharides (GOS) and high-molecular-weight fructo-oligosaccharides (FOS) can be detected in stool samples of formula-fed infants. The test formula was supplemented with 0.8 g/dl oligosaccharides (GOS+FOS). In the control formula, maltodextrins were used as placebo. Fecal flora was assessed at the beginning (day 1) and at the end of a 28-d feeding period (day 2). At day 2 the content of galacto- and fructo-oligosaccharides in the stool samples were measured. On study day 1, the number of bifidobacteria was not different among the groups (supplemented group: 7.7 (6.2) CFU/g; placebo group: 8.0 (6.0) CFU/g). At the end of the 28-d feeding period, the number of bifidobacteria was significantly higher in the group fed the supplemented formula when compared to placebo (supplemented group: 9.8 (0.7) CFU/g stool; placebo group: 7.1 (4.7) CFU/g stool; p<0.001). In all infants fed the supplemented formula, GOS and FOS could be identified in the stool samples. That was not the case in infants fed the non-supplemented formula. CONCLUSION: The present data confirm the bifidogenicity of oligosaccharides and indicate that dietary galacto-oligosaccharides and long chain fructo-oligosaccharides remain during the whole passage in the lumen of the gastrointestinal tract, similarly to human milk oligosaccharides. 相似文献
997.
François G Duclos P Margolis H Lavanchy D Siegrist CA Meheus A Lambert PH Emiroğlu N Badur S Van Damme P 《The Pediatric infectious disease journal》2005,24(11):953-961
In the years following the hepatitis B vaccination/multiple sclerosis controversy, a number of new issues regarding vaccine safety have been raised, in some cases leading to more debate and confusion. Against this background, an international group of experts was convened to review the current points of view concerning the use of thimerosal as a preservative and its potential risks; the suggested link between thimerosal-containing vaccines and acute lymphoblastic leukemia; the alleged association between aluminum-containing vaccines/macrophagic myofasciitis and general systemic complaints; a possible link between vaccination and autoimmune pathology; and a hypothetical link between measles-mumps-rubella vaccination and autism. At present, there are no data to conclude that childhood vaccines, and in particular hepatitis B vaccine, pose a serious health risk or justify a change in current immunization practice. However, vaccine "scares" continue to have an international impact on immunization coverage. Creating a positive environment for immunization can be achieved by repositioning the value of vaccines and vaccination, supported by evidence-based information. The role of international organizations, the media, and the industry in the implementation of communication strategies was discussed and the impact of litigation issues on vaccination was evaluated. The Viral Hepatitis Prevention Board confirms its commitment to current recommendations for universal and risk group hepatitis B vaccination and further encourages the conduct of vaccine safety studies and the dissemination of their results. 相似文献
998.
Although far from perfect, randomized clinical trials (RCTs) are the best mechanism available for evaluating the risk/benefit profile of a particular therapy. Given this, it is particularly unfortunate that there have been few clinical trials of therapy for myeloproliferative diseases (MPDs) as these therapies are often based on agents with unclear long-term safety. A complex profile of MPD uncertainties requires a simple, but articulated strategy of care and research to allow a reasonable transfer of the best available validated knowledge and a timely investigation of the most relevant questions. The multi-country, collaborative RCTs are key to generating valid data. The prerequisite for success is the close interaction of the clinical community and the research community studying the same patients. Data to be collected, criteria, contents, frequency of follow-up, and documentation of the events should be as similar as possible to those used in routine clinical care. One of the greatest achievements of the multicenter trials with this orientation has been to produce a "core" of data and practices, on which the main analyses will be made, but which at the same time reflect an optimal level of patient care for the majority of patients. 相似文献
999.
1000.
Koenen RR Christella M Thomassen LG Tans G Rosing J Hackeng TM 《Thrombosis and haemostasis》2005,93(5):853-859
We determined anticoagulant parameters that depend on protein S function in plasma, i.e. the APC-independent anticoagulant activity of protein S (expressed as pSR) and APC resistance determined with thrombin generation-based tests (expressed as APCsr) as well as plasma levels of total and free protein S and prothrombin in men, women not using oral contraceptives (OC), and in women using second or third generation OC. Thrombin generation in the APC resistance assays was initiated either with factor Xa (Xa-APCsr) or tissue factor (TF-APCsr). The APC-independent anticoagulant activity of protein S was highest in men (pSR=1.69) and gradually decreased from women not using OC (pSR=1.49) via women using second generation (pSR=1.35) to women using third generation OC (pSR=1.27). The pSR correlated inversely with nAPCsr determined with the tissue factor-based APC resistance test (TF-APCsr) but not with nAPCsr determined with the factor Xa-based assay (Xa-APCsr). Multiple linear regression analysis in which sex, OC use, and protein S and prothrombin levels were included as independent variables and the pSR, TF-APCsr or Xa-APCsr as dependent variables indicated that plasma protein S levels poorly predict the pSR and the TF-APCsr, but are the main determinant of the Xa-APCsr. This indicates that OC use alters the expression of protein S activity. This phenomenon can be caused by differences in modulation of the activity of protein S by other plasma proteins that change during OC use or by OC-induced changes in the protein S molecule that impair its anticoagulant activity. Functional impairment of protein S as a result of hormonal influence may, at least in part, contribute to the thrombotic risk of OC users. 相似文献