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21.
Laboratory detection of Haemophilus influenzae with decreased susceptibility to nalidixic acid, ciprofloxacin, levofloxacin, and moxifloxacin due to GyrA and ParC mutations 下载免费PDF全文
Pérez-Vázquez M Román F Aracil B Cantón R Campos J 《Journal of clinical microbiology》2004,42(3):1185-1191
The detection of clinical isolates with decreased fluoroquinolone susceptibilities and a resistance mechanism is of epidemiological and clinical interest. We studied the susceptibilities of 62 clinical isolates and 2 American Type Culture Collection reference strains of Haemophilus influenzae to ciprofloxacin, levofloxacin, moxifloxacin, and nalidixic acid by the microdilution and disk diffusion methods. The ciprofloxacin MICs for 34 of the isolates were >/=0.12 micro g/ml (range, 0.12 to 32 micro g/ml), and the ciprofloxacin MICs for 28 matched control isolates were =0.06 micro g/ml. In addition, we sequenced the quinolone resistance-determining regions (QRDRs) of gyrA and parC of all strains. The log(2) MICs of all quinolones were plotted against the inhibition zone diameters. The MICs and inhibition zone diameters selected to screen for the resistance mechanism were based on the susceptibility distribution data and the presence or absence of amino acid changes in the QRDRs of GyrA and ParC. Strains for which ciprofloxacin MICs were =0.06 micro g/ml, levofloxacin and moxifloxacin MICs were =0.03 micro g/ml, and nalidixic acid MICs were =2.0 micro g/ml lacked modifications in the QRDR of GyrA. In contrast, all strains for which ciprofloxacin, levofloxacin, and moxifloxacin MICs were >/=0.5 micro g/ml and the vast majority of those for which nalidixic acid MICs were >/=32 micro g/ml exhibited amino acid changes in GyrA and ParC. Nalidixic acid and the other three fluoroquinolones studied could be used to screen H. influenzae isolates for the detection of decreased susceptibilities to quinolones due to the acquisition of two amino acid changes in the QRDRs of GyrA and ParC (sensitivity, >95%; specificity, >80%). 相似文献
22.
Mycobacterium tuberculosis subverts the differentiation of human monocytes into dendritic cells 总被引:4,自引:0,他引:4
Mariotti S Teloni R Iona E Fattorini L Giannoni F Romagnoli G Orefici G Nisini R 《European journal of immunology》2002,32(11):3050-3058
Intracellular pathogens have developed strategies for evading elimination by the defenses of the host immune system. Here we describe an escape mechanism utilized by Mycobacterium tuberculosis that involves the interference with the generation of fully competent DC from monocytes. We show that monocytes infected with live M. tuberculosis differentiated into mature, CD83+ and CCR7+ DC (Mt-MoDC), but were characterized by a selective failure in the expression of the family of CD1 molecules. These cells also showed levels of MHC class II and CD80 (B7.1) that were reduced in comparison with LPS-matured DC. In addition, Mt-MoDC produced TNF-alpha and IL-10, but were unable to secrete IL-12. The generation of Mt-MoDC required the infection of monocytes with live M. tuberculosis, since infection with heat-killed bacteria partially abrogated the effects on monocyte differentiation. Interestingly, Mt-MoDC revealed an impaired antigen-presentation function as assessed by the reduced capability to induce proliferation of cord blood T lymphocytes. Further, naive T lymphocytes expanded by Mt-MoDC were unable to secrete cytokines, in particular IL-4 and IFN-gamma, suggesting that they could be ineffective in helping the macrophage-mediated killing of intracellular mycobacteria. Our results suggest that the interference with monocyte differentiation into fully competent DC is an evasion mechanism of M. tuberculosis that could contribute to its intracellular persistence by avoiding immune recognition. 相似文献
23.
Luca M. Sconfienza Domenico Albano Carmelo Messina Rocco D’Apolito Elena De Vecchi Luigi Zagra 《The Journal of arthroplasty》2021,36(8):2962-2967
BackgroundTo diagnose periprosthetic joint infection (PJI) preoperatively, ultrasound-guided joint aspiration (US-JA) may not be performed when effusion is minimal or absent. We aimed to report and investigate the diagnostic performance of ultrasound-guided periprosthetic biopsy (US-PB) of synovial tissue to obtain joint samples in patients without fluid around the implants.MethodsOne-hundred nine patients (55 men; mean age: 68 ± 13 years) with failed total hip arthroplasty (THA) who underwent revision surgery performed preoperative US-JA or US-PB to rule out PJI.ResultsSixty-nine of 109 patients had joint effusion and underwent US-JA, while the remaining 40 with dry joint required US-PB. Thirty-five of 109 patients (32.1%) had PJI, while 74/109 (67.9%) had aseptic THA failure. No immediate complications were observed in both groups. Technical success of US-PB was 100%, as the procedure was carried on as planned in all cases. Sensitivity, specificity, positive predictive value, negative predictive value, and accuracy of US-JA were 52.2%, 97.8%, 92.3%, 80.3%, and 82.6%, while for US-PB, they were 41.7%, 100%, 100%, 80%, and 82.5%, respectively, with no significant difference (P = .779). Using the final diagnosis as reference standard, we observed a moderate agreement with both US-JA (k = 0.56) and US-PB (k = 0.50).ConclusionWe present a novel US-guided technique to biopsy periprosthetic synovial tissue of failed THA to rule out PJI. We found similar diagnostic performance as compared with traditional US-JA. This supports future larger studies on this procedure that might be applied in patients without joint effusion. 相似文献
24.
Federico G. Usuelli Cristian Indino Alberto Leardini Luigi Manzi Maurizio Ortolani Paolo Caravaggi 《Foot and Ankle Surgery》2021,27(2):150-155
BackgroundIn severe cases of ankle and subtalar arthritis, arthrodesis of the subtalar joint is performed in combination with ankle arthroplasty. In these special cases gait analysis reveals real motion at the replaced tibiotalar joint.MethodsTwenty-three patients affected by ankle and subtalar arthritis, treated either with a 3-component or a 2-component prosthesis in combination with subtalar arthrodesis, were clinically evaluated preoperatively and at a minimum of 1-year follow-up. Gait analysis was performed postoperatively using a multi-segment foot protocol. Foot kinematics were compared to corresponding data from a healthy control group.ResultsClinical scores significantly improved from preoperative to follow-up. The clinically measured passive ankle dorsiflexion/plantarflexion significantly improved at the follow-up. Patients’ normalized walking speed and stride length were significantly lower than those in control. With exception of the ankle frontal-plane motion, sagittal-plane mobility of foot joints was about 50% than that in healthy joints.ConclusionsImprovement in clinical scores was found for both prostheses. Normal spatio-temporal parameters were not restored. In these patients, fusion of the subtalar joint appeared to be compensated by larger frontal-plane motion at the tibiotalar joint.Level of evidenceLevel III- retrospective comparative study.The study was approved by the local Ethics Committee as protocol MAT (protocol registration at clinicaltrials.gov NCT03356951). 相似文献
25.
Ostinelli Edoardo G. D’Agostino Armando Pesce Luisa Zangani Caroline Miragoli Paolo Durbano Federico Biffi Giuseppe Mencacci Claudio Scarone Silvio Gambini Orsola 《Zeitschrift fur Gesundheitswissenschaften》2021,29(6):1343-1355
Journal of Public Health - Neighbourhood composition is considered a social determinant of mental health that can be addressed by policymakers to improve outcomes. Deprived neighbourhoods typically... 相似文献
26.
C Messina 《Functional neurology》1990,5(3):217-223
Pathophysiology of muscle tone is discussed on the basis of recent knowledge about motor system organization. Decerebrate rigidity, "pyramidal" spasticity and extrapyramidal rigidity served as models of muscle tone alterations in lateral and ventral motor system lesions. 相似文献
27.
28.
G Saggese S Bertelloni GI Baroncelli G Federico 《Acta paediatrica (Oslo, Norway : 1992)》1992,81(6-7):532-535
Osteoporosis is a common finding in Turner's syndrome. To test the hypothesis that calcitonin deficiency may contribute to bone mineral loss in Turner's syndrome, we studied basal and calcium-stimulated (2 mg/kg body weight in 5 min) levels of total calcitonin, extractable calcitonin and katacalcin in 15 girls with Turner's syndrome and osteoporosis. Fifteen age-matched healthy girls were studied as controls. Both basal calcitonin (total and extractable) and katacalcin values were not significantly different in patients with Turner's syndrome in comparison with those of the controls. The calcium stimulation test showed a similar "C" cell secretory reserve in both groups. The calculation of delta CT/delta iCa of total and extractable calcitonin and delta KC/delta iCa, which accounts for individual variations in serum ionized calcium increases, did not show any significant difference between girls with Turner's syndrome and controls. We conclude that calcitonin deficiency is not a causative factor of osteoporosis in girls with Turner's syndrome and that in this syndrome long-life estrogen deficiency does not impair "C" cell secretory activity. 相似文献
29.
F. Federico D. Pedone P. Lamberti P. Achille M. Camicia A. Carella E. Ferrari 《Journal of neurology》1982,226(4):283-287
Summary Neurological complications following rubella are only rarely encountered. However, in many cases severe neurological impairment may occur, leading to permanent disability. In a recent epidemic of rubella in Israel during the years 1978–1979, 20 patients with severe neurological complications have been seen. We report on 5 cases of which 3 are described in detail. Considering the efficacy of immunization against rubella, we suggest that in countries such as England and Israel in which periodic epidemics of rubella occur, a generalized plan of immunization should be undertaken during the first years of life. Such an approach will prevent the neurological complication of congenital, as well as acquired, rubella infection.
Zusammenfassung Obwohl neurologische Komplikationen nur selten nach Rubella erscheinen, sind sie in vielen Fällen schwer und können zu permanenten neurologischen Schäden führen. In einer Rubella-Epidemie, die kürzlich in Israel auftrat (1978–1979), wurden 20 Fälle von schweren neurologischen Komplikationen festgestellt. Wir berichten über 5 dieser Fälle, 3 von ihnen in ausführlicher Weise. Nachdem Rubella-Impfung sehr wirksam ist, schlagen wir vor, daß in Ländern wie Israel oder England, in denen Epidemien von Zeit zu Zeit auftreten, ein allgemeiner Impfungsplan für die ersten Lebensjahre eingeführt wird. So ein Plan kann die neurologischen Komplikationen nach kongenitaler oder erworbener Rubella verhindern.相似文献
30.
The Authors compare the results obtained between two groups of patients suffering from leg lipodystrophy, who were subjected
to a reducing lipoplasty. In the first group, surgeons made use of a new sort of cannula, deprived of the classical grip,
whereas in the second group, they employed the traditional probe. The best results, achieved with the first group, prove this
new operating system is really effective, particularly on legs, for the following reasons:
(1) Higher precision and better control of the instrument
(2) Swan-neck cannula abolition
(3) Opportunity to operate with both hands
(4) Halved operating time
(5) No tiredness after the operation. 相似文献