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41.
Deoxyribonucleic acid amplification and hybridisation in Crohn''s disease using a chlamydial plasmid probe. 总被引:1,自引:1,他引:0 下载免费PDF全文
The possibility that Crohn's disease is caused by infection with Chlamydia trachomatis was examined by probing for chlamydial plasmid deoxyribonucleic acid (DNA) in DNA extracts from Crohn's disease tissue and by means of a serological study. Gut DNA extracts were obtained from 10 patients with Crohn's disease and four control subjects and were probed with a chlamydial plasmid probe after Southern blotting. The polymerase chain reaction was also used to amplify any chlamydial plasmid DNA present in tissue DNA extracts, before Southern blotting and probing. Chlamydial proctitis control specimens were not available: gut DNA extracts mixed with traces of chlamydia plasmid served as positive controls. Using these techniques, no chlamydial plasmid DNA sequences were found in Crohn's disease tissue. An enzyme linked immunosorbent assay for C trachomatis LI was performed on 48 patients with Crohn's disease and 48 control subjects. Seropositivity was present in 14.6% of patients and 29% of control subjects and was not statistically significant (p greater than 0.05). The failure to show chlamydial DNA and the lack of serological response to chlamydia make C trachomatis infection a very unlikely factor in the pathogenesis of Crohn's disease. 相似文献
42.
Hypo- and hyperthyroidism have been associated with changes in the activities of mitochondrial enzymes in homogenates of skeletal muscles, but it is unclear whether such changes were due to changes in single fibre enzyme activities or to previously documented changes in relative numbers of fibres. In this study the activities of the mitochondrial enzymes alpha-glycerol phosphate dehydrogenase (m-alpha GPDH) and succinate dehydrogenase (SDH) were measured in single fibres of the soleus and gastrocnemius muscles of the rat by cytochemical assays. In the soleus muscles of hypothyroid animals there was a decrease in the mean percentage (+/- S.D.) of type II fibres from 8.0 +/- 6.0 to 0.8 +/- 1.9% (P less than 0.05) and decreases in SDH activities in all fibre types (P less than 0.005). In the gastrocnemius muscles of these animals there were no changes in fibre composition but type IIB fibres had reduced (P less than 0.05) m-alpha GPDH activities. In the hyperthyroid animals, in which body weight had increased relative to the euthyroid animals, there were increases in the percentages of type IC and type II fibres in the soleus from 4.3 +/- 1.7 to 13.1 +/- 9.0% (P less than 0.05) and from 9.6 +/- 7.2 to 33.4 +/- 9.6% (P less than 0.005) respectively and an increase in the percentage of type IIA fibres in the gastrocnemius from 92.9 +/- 2.3 to 97.0 +/- 2.9% (P less than 0.05). However, there were no increases in single fibre mitochondrial enzyme activities.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
43.
Afferent projections to the thalamic lateral dorsal nucleus were examined in the rat by the use of retrograde axonal transport techniques. Small iontophoretic injections of horseradish peroxidase were placed at various locations within the lateral dorsal nucleus, and the location and morphology of cells of origin of afferent projections were identified by retrograde labeling. For all cases examined, subcortical retrogradely labeled neurons were most prominent in the pretectal complex, the intermediate layers of the superior colliculus, and the ventral lateral geniculate nucleus. Labeled cells were also seen in the thalamic reticular nucleus and the zona incerta. Within the cerebral cortex, labeled cells were prominent in the retrosplenial areas (areas 29b, 29c, and 29d) and the presubiculum. Labeled cells were also seen in areas 17 and 18 of occipital cortex. Peroxidase injections in the dorsal lateral part of the lateral dorsal nucleus result in labeled neurons in all of the ipsilateral pretectal nuclei, but especially those that receive direct retinal afferents. Labeled cells were also seen in the ventral lateral geniculate nucleus and the rostral tip of laminae IV-VI of the superior colliculus. In contrast, peroxidase injections in ventral medial portions of the lateral dorsal nucleus result in fewer labeled pretectal cells, and these labeled cells are found exclusively in the pretectal nuclei that do not receive retinal afferents. Other labeled cells following injections in the rostral and medial portions of the lateral dorsal nucleus are seen contralaterally in the medial pretectal region and nucleus of the posterior commissure, and bilaterally in the rostral tips of laminae IV and V of the superior colliculus. Camera lucida drawings of HRP labeled cells reveal that projecting cells in each pretectal nucleus have a characteristic soma size and dendritic branching pattern. These results are discussed with regard to the type of sensory information that may reach the lateral dorsal nucleus and then be relayed on to the medial limbic cortex. 相似文献
44.
H Gilljam O Andersson A Ellin B Robertson B Strandvik 《Clinica chimica acta; international journal of clinical chemistry》1988,176(1):29-37
Bronchial secretions from seven patients with cystic fibrosis (CF) were aspirated by fibreoptic bronchoscopy and analysed for lipid composition. The total lipid fraction was also used to measure dynamic surface tension. Pooled samples from 'normal' patients, healthy volunteers, patients with chronic bronchitis, and individual samples from two patients with bronchiectasis were used as controls. Increased bronchial inflammation and infection correlated with a decrease of the phospholipid fraction, and an increase of the cholesterol, diglyceride and triglyceride fractions. When individual phospholipids were analysed, patients with clinically severe CF showed a markedly decreased phosphatidylcholine fraction, whereas the phosphatidylinositol fraction was significantly higher in CF patients than in controls (p less than 0.05). Minimum surface tension was higher in CF patients compared to patients with chronic bronchitis (p less than 0.05). This might be related to earlier reported specific changes in the pattern of fatty acids of the CF bronchial phospholipids. 相似文献
45.
Value of endoscopic surveillance in the detection of neoplastic change in Barrett's oesophagus 总被引:9,自引:0,他引:9
C S Robertson J F Mayberry D A Nicholson P D James M Atkinson 《The British journal of surgery》1988,75(8):760-763
Fifty-six patients with Barrett's oesophagus diagnosed between 1977 and 1986 were prospectively studied by 6-monthly endoscopic surveillance and biopsy. During follow-up to-date, four patients have developed high-grade dysplasia and three have adenocarcinoma of the oesophagus. Two of the adenocarcinomas were preceded by progressively severe dysplastic changes but in the third no dysplasia had been previously detected. The incidence of adenocarcinoma was 1 per 56 patient-years of follow-up. Changes in symptomatology or gross endoscopic appearances were usually absent, even after adenocarcinoma had developed, indicating that biopsy is essential for early diagnosis. The high risk of malignant change makes endoscopic surveillance advisable in all patients with Barrett's oesophagus. 相似文献
46.
Design and fabrication of cementless hip stems 总被引:4,自引:1,他引:3
Theoretical and experimental studies before and after stem insertion demonstrated that stresses and strains were closer to normal for uncemented stems than for cemented stems. The values were affected by relative tightness of fit in the proximal and distal regions and by the presence or absence of a collar. For designing an optimal fit-stem, the average femoral geometry was first determined. The stem was used in a photoelastic coating study that showed a continuous strain field over the bone surface. The average proximomedial bone strains for intact, press-fit, loose press-fit with collar, and proximally cemented (to simulate ingrowth) designs were 100%, 65%, 101%, and 54%, respectively. Localized patches of high strain were seen on the proximal bone surface and beneath a collar, indicative of localized stem-bone contact points. 相似文献
47.
Functional changes in slow-twitch soleus and fast-twitch extensor digitorum longus muscles were assessed after 2 mo of streptozocin-induced diabetes in rats. For soleus, there was a slowing of twitch times both for contraction and relaxation and a reduction of maximum tetanic relaxation rate. There was little effect on strength performance assessed by maximal tetanic tension production. Treatment with the aldose reductase inhibitor ponalrestat largely prevented relaxation defects but had little effect on contraction. For the fast muscle, twitch times were relatively unaffected, but maximum tetanic relaxation rate was reduced. In addition, tetanic tension output decreased. These changes were largely prevented by ponalrestat treatment. The effects of partial insulin therapy were also investigated. This regimen reduced hypoinsulinemia, but sufficient hyperglycemia remained to stimulate the polyol pathway. It prevented the slowing of soleus twitch contraction but had no effect on relaxation. For extensor digitorum longus, insulin produced further deleterious effects on tetanic tension and maximum relaxation rate, which were antagonized by ponalrestat. A 1% dietary myo-inositol supplement had little effect on contractile function in slow or fast muscles. It was concluded that polyol-pathway activity is an important factor underlying skeletal muscle functional changes in diabetes, probably acting through disruption of Ca2+ handling. Hypoinsulinemia was considered a secondary factor causing atrophy, particularly of fast muscles. There was no evidence of effects dependent on neuropathy. 相似文献
48.
49.
Therapeutic response in patients with advanced breast cancer is conventionally assessed with reference to criteria devised by the International Union Against Cancer. Evidence to date suggests, however, that assessments of equivalent quality may be obtained at lower cost from the use of serum markers. The paper presents estimates of potential cost savings resulting from the use of serum markers in place of conventional assessment and argues that the size of these savings merits the establishment of a randomised controlled trial. 相似文献