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D Van Neste† RM Trüeb‡ 《Journal of the European Academy of Dermatology and Venereology》2006,20(5):578-583
BACKGROUND: Computer-assisted image analysis has been proposed for human hair growth studies. METHODS: The performances of Trichoscan, a commercially available automated system combining epiluminiscence microscopy with digital image analysis, developed for office-based hair growth measurements, have been evaluated comparatively on the same skin sites using standardized photographic equipment and calibrated processing for contrast-enhanced phototrichogram (CE-PTG) analysis. This reference method has been validated with scalp biopsies and histological examination of serial sectioning. RESULTS: Besides edge effects, hair fibres escaped the Trichoscan analysis for various reasons including, but not limited to, thickness, pigmentation, closeness and crossing. CONCLUSION: Most of these problems have been identified in the late 1980s and remain largely unsolved by the processing software that was evaluated in 2004. Therefore claims promoting the Trichoscan method for accurate hair measurements in clinical trials on scalp and body hair are not supported by the present investigation. The speed at which the analysis is performed is outweighed by the errors in signal detection. Therefore we suggest that improvements must be clearly documented before Trichoscan is established for quantified diagnostic purposes and detailed hair cycle monitoring during hair trials. 相似文献
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Sudden coronary death in Glasgow: the severity and distribution of chronic coronary atherosclerotic stenoses. 下载免费PDF全文
A detailed analysis of the extent of coronary artery atherosclerosis was made in 92 white subjects (66 men and 26 women) who died suddenly from ischaemic heart disease. Stenoses resulting in loss of greater than or equal to 75% of luminal cross sectional area (significant stenosis) were found in 90 subjects and these were more extensive in the proximal coronary tree than in the distal. Thirty nine per cent had triple vessel disease, 37% had double vessel disease, and 23% had single vessel disease. In addition one man had an isolated significant stenosis affecting the left main coronary artery. The frequency of significant stenoses in the left main coronary artery was greater in men than in women. The arteries that were least affected were the distal branches of the right coronary artery. A notable feature was the widespread nature of the coronary atherosclerosis: only 26 of the total of 1840 segments of coronary artery examined in the 92 victims could be described as having a normal intima (less than or equal to 10% loss of the area within the internal elastic lamina). 相似文献
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V Schleyer† S Radakovic-Fijan‡ S Karrer† T Zwingers§ A Tanew‡ M Landthaler† RM Szeimies† 《Journal of the European Academy of Dermatology and Venereology》2006,20(7):823-828
BACKGROUND: Based on good results in the treatment of superficial skin tumours, since the early 1990s topical photodynamic therapy with aminolaevulinic acid (ALA PDT) has been used for disseminated, inflammatory dermatoses including psoriasis. However, there is still a lack of well-documented trials. OBJECTIVE: A prospective randomized, double-blind phase I/II intrapatient comparison study was conducted in 12 patients to investigate whether topical ALA PDT is an effective treatment for chronic plaque-type psoriasis. METHODS: In each patient three psoriatic plaques were randomly treated with a light dose of 20 J/cm(2) and 0.1%, 1% and 5% ALA, respectively. Treatment was conducted twice a week until complete clearance or for a maximum of 12 irradiations. Therapeutic efficacy was assessed by weekly determination of the psoriasis severity index (PSI). RESULTS: The mean percentage improvement was 37.5%, 45.6% and 51.2% in the 0.1%, 1% and 5% ALA-treated groups, respectively. Irradiation had to be interrupted several times because of severe burning and pain sensation. CONCLUSION: Topical ALA PDT did not prove to be an appropriate treatment option for plaque-type psoriasis due to disappointing clinical efficacy, the time-consuming treatment procedure and its unfavourable adverse event profile. 相似文献
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A comparison of three methods of repairing the hard palate. 总被引:2,自引:0,他引:2
R W Pigott E H Albery I S Hathorn N E Atack A Williams K Harland A Orlando S Falder B Coghlan 《The Cleft palate-craniofacial journal》2002,39(4):383-391
OBJECTIVE: To compare growth, speech, and nasal symmetry outcomes of three methods of hard palate repair. PATIENTS: Consecutive available records of children born with unilateral bony complete cleft lip and palate over the period 1972 to 1992. INTERVENTIONS: Identical management of lip, nose, alveolus, and soft palate. Hard palate repair by Cuthbert Veau (CV) from 1972 to 1981, von Langenbeck (vL) from 1982 to 1989, or medial Langenbeck (ML) from 1989 to 1991. OUTCOME MEASURES: For growth: GOSLON yardstick or 5-year model index. For speech: articulation test. Nasal anemometry. For nasal symmetry: Coghlan computer-based assessment. All these measures were developed during the period of data collection but not for this project. RESULTS: There was a strong trend toward more favorable anteroposterior maxillary growth with the change from CV to vL to ML techniques. This fell short of statistical significance because of the small sample size. There was a significant reduction in cleft-related articulation faults (p =.01) considered to be related to improved arch form. In the absence of improved rates of velopharyngeal insufficiency or nasal symmetry, increased surgical experience was discounted as a significant contribution to improved growth and articulation outcomes. CONCLUSIONS: Reduced periosteal undermining and residual exposed palatal shelf from CV to vL to ML improved incisor relationships and articulation. 相似文献