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1.
Akira Sawaki Nobumasa Mizuno Kuniyuki Takahashi Tsuneya Nakamura Masahiro Tajika Hiroki Kawai Toshifumi Isaka Hiroshi Imaoka Yasuyuki Okamoto Masatoshi Aoki Hiroyuki Inoue Ahmed AS Salem Yasushi Yatabe Kenji Yamao 《Digestive endoscopy》2006,18(1):40-44
Background: Gastrointestinal stromal tumors (GIST) are one of the most common mesenchymal tumors of the gastrointestinal tract. GIST are defined by positive immunohistochemical staining for KIT or CD34 and thus are generally diagnosed after surgery. Because small GIST are rarely diagnosed before surgery, the clinical course of these small tumors is not clear. The aim of the present study was to follow changes in size and configuration of small GIST that were pathologically confirmed using endoscopic ultrasonography‐guided fine‐needle aspiration biopsy (EUS‐FNAB). Methods: Between July 1997 and December 2003, 16 tumors in 16 patients (10 men and 6 women) with an immunohistochemical diagnosis of GIST were regularly followed in our hospital. The median patient age when EUS‐FNAB was performed was 62 years (range 26–82 years) and the median follow‐up period was 4.9 years (range 0.5–9.6 years). Results: Fourteen tumors showed no remarkable changes in size and shape during follow up compared with the initial diagnosis. Two tumors enlarged: one tumor approximately doubled its diameter in 8 years and the other tumor increased from 1.8 cm at diagnosis to up to 10 cm after only 2 years. Doubling time of the latter tumor was calculated as 3.1 months. Conclusions: We conclude that EUS‐FNAB might be a good modality for final diagnosis of GIST without surgery, and that GIST without rapid growth on follow up can be endoscopically followed. 相似文献
2.
The ontogeny of type I and type II benzodiazepine binding sites was studied in mouse cerebellum by displacement of [3H]flunitrazepam binding by zolpidem, a ligand specific for the type I sites. Type I binding sites predominate throughout development and in the adult while type II sites account for 25% of total cerebellar benzodiazepine binding sites at birth and, during development, decrease to 10% or less in the adult. On a per cerebellum basis type II sites increase during the first postnatal week and then remain at a steady level while type I sites increase until adulthood. These results may indicate a specific localization of the type II sites (and of the corresponding alpha-protein subunits in the GABA/benzodiazepine receptor complex) in structures already present at birth and developing during a short early postnatal period. The affinity of zolpidem for its high affinity (type I) binding sites increases during cerebellar ontogeny, this increase possibly indicates an epigenetic (post-translational) 'maturation' process of the corresponding receptor molecule. Hill numbers indicate the existence of an additional binding site heterogeneity greater during development but still present in the adult; probably this is to be related to the simultaneous presence of different 'maturation' stages during development and with a certain variety of the final products. 相似文献
3.
Coronary artery bypass grafts: visualization with MR imaging 总被引:1,自引:0,他引:1
4.
Here we describe an error-compensating kinetic-based method for the enzymatic quantification of creatinine in serum. The method, which has a large linear range and very low dependency on experimental variables that influence enzyme activity, is based on the use of creatinine amidohydrolase in a four-step coupled reaction sequence to generate a product that is monitored photometrically. We collected data for absorbance vs time during two to four half-lives of each reaction and fit a first-order model to the data to compute the total absorbance change that would be measured if the reaction were monitored to completion. Computed values of absorbance change agreed well with measured values and varied linearly with creatinine concentration in the sample throughout the range examined: 44 to 1326 mumol/L. A twofold change in enzyme activity in the final reaction mixture (3.3 to 6.6 kU/L) produced changes of only 12% and 4% for creatinine concentrations of 44 and 353 mumol/L, respectively. Results (y) for 39 serum samples that contained creatinine concentrations between 20 and 1800 mumol/L agreed well with liquid-chromatographic results (x), yielding linear least-squares statistics of y = (1.03 +/- 0.01) x + (5 +/- 5) mumol/L (r = 0.995, Sy.x = 37 mumol/L). We conclude that the predictive kinetic approach is a robust method for the quantification of creatinine in serum. 相似文献
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An alloantiserum, termed R2, specifically agglutinates red blood cells (RBC) from line 100B chickens that are susceptible to avian leukosis viruses (ALV) belonging to subgroups B and E, but does not agglutinate RBC from congenic inbred line 7(2 )chickens that are resistant to ALV B and E. The R2 antigen was also detected on lymphocytes and thrombocytes. Using chickens from a special cross, it was found that R2 reactivity requires that the chickens must: (1) be susceptible to infection by ALV-E; and (2) express a viral envelope gene with subgroup E specificity. With R2 antiserum, a nearly perfect association was observed between agglutination and susceptibility to ALV-B in F(2) chickens containing endogenous viral genes ev2 and/or ev3. These results support earlier evidence that ALV-B and ALV-E share receptors. Moreover, the R2 antiserum was shown to neutralize ALV-E. The R2 antigen showed Mendelian segregation in chickens of a commercial White Leghorn strain-cross containing ev3, ev6 and ev9. However, commercial chickens with or without the R2 antigen did not differ in susceptibility to lymphoid leukosis induction or immune response on infection with ALV of subgroup A for complex reasons we discuss. 相似文献
9.
Down-regulation of c-MYC antigen expression in lymphocytes of Emu-c-myc transgenic mice treated with anti-c-myc DNA methylphosphonates. 总被引:4,自引:0,他引:4
In transgenic mice bearing a murine immunoglobulin enhancer/c-myc fusion transgene (Emu-myc), it was found that antisense DNA methylphosphonates targeted against c-myc mRNA inhibited production of c-MYC protein in peripheral lymphocytes. The decrease in protein was measured 3-4 h after i.v. administration of a 300-nmol dose. c-MYC was detected by immunofluorescence of fixed cells stained with an anti-c-MYC antiserum. In addition, DNA methylphosphonates did not induce acute toxicity following i.v. administration of a 300-nmol dose. An identically administered scrambled sequence oligomer did not decrease c-MYC protein or induce toxicity. Finally, recovery of DNA methylphosphonates from the blood plasma of treated mice indicated that the oligomers remained intact up to 3 h, while their concentrations decreased rapidly for the first h, then slowly decreased over the next 2 h. This is the first demonstration of sequence-specific antisense DNA methylphosphonate inhibition of gene expression in the bloodstream of an animal model. 相似文献
10.
The aetiopathogenesis of haemorrhagic shock encephalopathy syndrome (HSES) remains unclear and after concern that a novel environmental agent was the cause, the British Paediatric Association and the Public Health Laboratory Service Communicable Disease Surveillance Centre in 1983 initiated surveillance of this condition in the British Isles. After 1986 cases were ascertained via the British Paediatric Surveillance Unit 'active' reporting scheme; this report presents the findings for 1985-8. Sixty five patients were reported, of whom 52 satisfied the criteria for inclusion. Of those whose outcome was known, 24 (46%) died, 18 had severe neurological damage, and six survived apparently intact. Epidemiological features of note were: the median age of 15 weeks (range 3-140); statistically significant clustering of admission times suggesting a peak onset period at night; lack of geographic clusters, of secular trends and, except for a slight excess in winter months, of seasonality. Clinical and pathological features followed a highly consistent pattern, suggesting that HSES is an individual clinical entity distinguishable from conditions with similar presentations, such as septicaemia and Reye's syndrome. There was no microbiological or epidemiological evidence to support the emergence of a novel environmental agent. Many of the features of HSES were, however, the same as those described in heat stroke and we suggest that the two conditions are the same even though there is usually no history of overt overheating. 相似文献