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411.
Meeuwsen S Persoon-Deen C Bsibsi M Bajramovic JJ Ravid R De Bolle L van Noort JM 《Journal of neuroimmunology》2005,164(1-2):37-47
Human herpesvirus-6A (HHV-6A) is a common pathogen whose role in CNS disorders including multiple sclerosis remains controversial. To understand how HHV-6A could influence inflammatory pathways in the CNS, we infected cultured human adult astrocytes and examined the expression of 268 cytokines, chemokines, growth factors and their receptors by gene profiling. HHV-6 infection alone had little effect on the astrocyte gene profile but strongly altered the astrocyte response to proinflammatory cytokines. Under those conditions astrocytes express higher levels of anti-inflammatory mediators including IL-10 and IL-11, chemotactic factors, growth factors and factors controlling type I interferon production. Our data suggest that HHV-6 itself does not evoke a pro-inflammatory response in astrocytes but rather triggers immune modulatory factors in the face of inflammation. 相似文献
412.
Interventricular septal configuration at mr imaging and pulmonary arterial pressure in pulmonary hypertension 总被引:8,自引:0,他引:8
Roeleveld RJ Marcus JT Faes TJ Gan TJ Boonstra A Postmus PE Vonk-Noordegraaf A 《Radiology》2005,234(3):710-717
PURPOSE: To investigate whether a relationship exists between septum shape and systolic pulmonary arterial pressure (PAP) in patients with pulmonary hypertension. MATERIALS AND METHODS: Study protocol was approved by institutional ethics review committee; all patients gave informed consent. Right-sided heart catheterization with vasodilator testing was performed in 39 adult subjects suspected of having pulmonary hypertension. There were 11 men and 28 women, aged 21-75 years (mean, 46 years). Only two patients showed favorable response to vasodilators, defined by a decrease in PAP of more than 20%. Synchronous right- and left-ventricular pressure measurements and four-chamber magnetic resonance (MR) imaging were used to identify timing of maximal leftward ventricular septal bowing within cardiac cycle. Septal bowing was evaluated with MR, measured on short-axis cine heart images, and expressed as curvature (reciprocal of radius). Curvature was quantified on one image (the one that showed the most severe distortion of normal septal shape). The relationship between systolic PAP and septal curvature was tested with linear regression analysis. P <.05 was considered to indicate a statistically significant difference. RESULTS: Of 39 subjects, 37 had pulmonary hypertension. Maximal distortion of normal septal shape was found during right ventricular relaxation phase. Systolic PAP was proportional to septal curvature: r=0.77 (P < .001), slope=-114.7, and intercept=67.2. In the two vasodilator responsive subjects, a significant reduction of leftward ventricular septal bowing was observed in response to reduction of right ventricular pressure. CONCLUSION: In 37 patients with pulmonary hypertension, systolic PAP higher than 67 mm Hg may be expected when leftward curvature is observed. 相似文献
413.
BACKGROUND: The injury rate in soccer is high, and effective injury prevention methods are needed. PURPOSE: To test the effect of a video-based awareness program on the incidence of acute injuries in soccer. STUDY DESIGN: Randomized control trial; Level of evidence, 1. METHODS: Participants were elite male soccer players from the top 2 divisions in Iceland. Fifteen of 20 teams completed the study: 7 intervention teams (127 players) and 8 control teams (144 players) chosen by random. Just before the start of the 2000 soccer season, the intervention teams were visited with an intervention program. The program included a 15-minute presentation with information on the injury risk of playing elite soccer, typical injuries, and their mechanisms. Then the players worked together in pairs and analyzed video sequences to develop preventive strategies. The 12 video sequences were selected from the previous Icelandic soccer season, representing 3 typical injury mechanisms that accounted for more than half of all incidents recorded. During the season, team physical therapists prospectively recorded all acute injuries, and coaches recorded training exposure on a special form. Injury incidence was compared between groups and between the 1999 and 2000 seasons for teams that participated in both seasons. RESULTS: No difference was observed in injury incidence between the intervention (6.6 +/- 0.7 injuries per 1000 player hours) and control groups (6.6 +/- 0.7 injuries per 1000 player hours). Furthermore, there was no difference in injury location or type. CONCLUSION: The video-based injury awareness program showed no effect on injury rate. 相似文献
414.
Prevalence of jumper's knee among elite athletes from different sports: a cross-sectional study 总被引:9,自引:0,他引:9
BACKGROUND: The prevalence of jumper's knee across different sports has not been examined, and it is not known if there is a gender difference. Data from surgical case series indicate that there may be a high prevalence in sports with high speed and power demands. HYPOTHESIS: The aim of this study was to estimate the prevalence of jumper's knee in different sports among female and male athletes and to correlate the prevalence to the loading characteristics of the extensor mechanism in these sports. STUDY DESIGN: Cross-sectional study; Level of evidence, 4. METHODS: The authors examined approximately 50 Norwegian male and female athletes at the national elite level from each of the following 9 sports: athletics (male athletes: high jump, 100- and 200-m sprint), basketball (male athletes), ice hockey (male athletes), volleyball (male athletes), orienteering (male athletes), road cycling (male athletes), soccer (male and female athletes), team handball (male and female athletes), and wrestling (male athletes). The examination included an interview on individual characteristics (weight, age, height, and training background), a clinical examination, and self-recorded Victorian Institute of Sport Assessment score from 0 (worst) to 100 (best). RESULTS: The overall prevalence of current jumper's knee was 14.2% (87 of 613 athletes), with a significant difference between sports with different performance characteristics (range, 0%-45%). In addition, 51 athletes (8%) reported previous symptoms. The prevalence of current symptoms was highest in volleyball (44.6%+/-6.6%) and basketball (31.9%+/-6.8%), whereas there were no cases in cycling or orienteering. The prevalence of current jumper's knee was lower among women (5.6%+/-2.2%) compared with men (13.5%+/-3.0%; chi2 test, P=.042). The duration of symptoms among athletes with current jumper's knee (n=87) was 32+/-25 (standard deviation) months, with a Victorian Institute of Sport Assessment score of 64+/-19. CONCLUSION: The prevalence of jumper's knee is high in sports characterized by high demands on speed and power for the leg extensors. The symptoms are often serious, resulting in long-standing impairment of athletic performance. 相似文献
415.
416.
Merkel cell carcinoma 总被引:1,自引:0,他引:1
Barile P Leroy C Bolle S Arrese JE Hermanns-Le T Piérard GE Duchesne B 《Journal fran?ais d'ophtalmologie》2004,27(4):432-436
Merkel cell carcinoma is a neuroendocrine tumor of the skin, originating from neuroendocrine cells. A case report of Merkel cell carcinoma, discovered in a 77-Year-old woman, was diagnosed and confirmed on a biopsy. Diagnostic and therapeutic orientations of this unusual but malignant tumor are described. 相似文献
417.
Fukami Miriam H.; Eikhom Thor S.; Ekanger Roald; Flatmark Torgeir; Nilsson Astrid 《Carcinogenesis》1986,7(9):1441-1446
The time course of changes in a number of biochemical parametersin rat liver was studied during 10 days of clofibrate administration.Ornithine decarboxylase (ODC) and putrescine levels began toincrease within hours of the first dose and reached maxima atabout 36 h (40 and 10 times control levels, respectively) andthen returned to normal levels by 48 h. This ODC induction byclofibrate is different from that seen in compensatory liverhyperplasia or diethylnitros-amine administration in that itwas not accompanied by elevations in cAMP or increased activationof cytoplasmk cAMP-dependent protein kinases, type I or II.Messenger RNA levels, notably of the species coding for theenzymes of the peroxisomal ß-oxidation pathway, increasedin parallel with ODC and putrescine to reach a maximum alsoat 36 h. The enzymes of the peroxisomal ß-oxidationpathway, on the other hand, increased more gradually over timeto reach a plateau at {small tilde} 7 10 days. The magnitudeof increase in mRNA (about 7-fold) was comparable to that ofperoxisomal ß-oxidation as measured by cyanide-insensitivepalmitoyl-CoA-dependent NAD+ reductase activity; comparableincreases in the specific content of enoyl-CoA hydratase: ß-hydroxyacyl-CoAdehydrogenase and of peroxisomal thiolase were observed, asdetermined by SDS electrophoresis. A gradual increase in long-chainacylCoA (1.5-fold) followed the increase in ß-oxidation,whereas a 2-fold increase in acid-soluble CoA (free CoA andshort-chain acyl-CoA) was seen as early as 36 h. This sequenceof changes is at variance with proposals that increased levelsof long-chain acyl-CoA mediate induction of peroxisomal ß-oxidation. 相似文献
418.
419.
CR1 were purified from sciatic nerve extracts by monoclonal antibody affinity chromatography. The effect of CR1 on complement-mediated haemolysis was studied by adding purified CR1 to a mixture of human serum as source of complement and sheep erythrocytes sensitized with rabbit IgG. A dose-dependent inhibition of the haemolysis occurred. There was no effect on the haemolysis when phosphate-buffered saline, elution buffer or run-through fraction not containing CR1 was added. Addition of a polyclonal anti-CR1 antibody to purified CR1 suppressed the inhibiting activity, strongly indicating that peripheral nerve CR1 inhibit complement-mediated haemolysis. This may be of great importance in vivo since CR1 present on the Schwann cell membrane may prevent the formation of terminal lytic complexes. 相似文献
420.