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71.
M. Gabrielli M. Candelli F. Franceschi F. Cremonini E. C. Nista L. Santarelli 《Scandinavian journal of gastroenterology》2013,48(6):605-606
Background: Irritable bowel syndrome is a common cause of abdominal pain and discomfort and may be related to disordered gastrointestinal motility. Our aim was to assess the effects of long-term treatment with a prokinetic agent, cisapride, on postprandial jejunal motility and symptoms in the irritable bowel syndrome (IBS). Methods: Thirty-eight patients with IBS (constipation-predominant, n = 17; diarrhoea-predominant, n = 21) underwent 24-h ambulatory jejunal manometry before and after 12 week's treatment {cisapride, 5mg three times daily (n = 19) or placebo (n = 19)}. Results 相似文献
72.
A single bifunctional enzyme, PilD, catalyzes cleavage and N-methylation of proteins belonging to the type IV pilin family. 总被引:28,自引:0,他引:28
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M S Strom D N Nunn S Lory 《Proceedings of the National Academy of Sciences of the United States of America》1993,90(6):2404-2408
Precursors of the type IV pilins of a number of bacterial pathogens, as well as related proteins involved in extracellular protein export and DNA uptake, are synthesized with short basic leader sequences. Maturation of these proteins involves two consecutive posttranslational modifications. The leader sequence is first proteolytically removed by specialized endopeptidases, of which the prototype is encoded by the pilD gene of Pseudomonas aeruginosa. Subsequently, the amino termini of these proteins are methylated. Here we demonstrate that PilD, in addition to cleaving the amino-terminal leader sequences of prepilin, also catalyzes N-methylation of the amino-terminal phenylalanine of the mature pilin, using S-adenosyl-L-methionine as a methyl donor. Thus, to our knowledge, PilD is the first characterized bacterial N-methyltransferase. Complete inhibition of N-methylation, but not peptide cleavage, by structural analogues of S-adenosyl-L-methionine suggests that PilD is a bifunctional enzyme with proteolytic and methylation activities carried out within two distinct active sites. 相似文献
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Joshua LaBaer QingQing Qiu Anukanth Anumanthan Wenhong Mar Dongmei Zuo T.V.S. Murthy Helen Taycher Allison Halleck Eugenie Hainsworth Stephen Lory Leonardo Brizuela 《Genome research》2004,14(10B):2190-2200
Pseudomonas aeruginosa, a common inhabitant of soil and water, is an opportunistic pathogen of growing clinical relevance. Its genome, one of the largest among bacteria [5570 open reading frames (ORFs)] approaches that of simple eukaryotes. We have constructed a comprehensive gene collection for this organism utilizing the annotated genome of P. aeruginosa PA01 and a highly automated and laboratory information management system (LIMS)-supported production line. All the individual ORFs have been successfully PCR-amplified and cloned into a recombination-based cloning system. We have isolated and archived four independent isolates of each individual ORF. Full sequence analysis of the first isolate for one-third of the ORFs in the collection has been completed. We used two sets of genes from this repository for high-throughput expression and purification of recombinant proteins in different systems. The purified proteins have been used to set up biochemical and immunological assays directed towards characterization of histidine kinases and identification of bacterial proteins involved in the immune response of cystic fibrosis patients. This gene repository provides a powerful tool for proteome- and genome-scale research of this organism, and the strategies adopted to generate this repository serve as a model for building clone sets for other bacteria. 相似文献
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Randomized trial of chemotherapy versus chemotherapy plus radiotherapy for stage I-II Hodgkin's disease 总被引:1,自引:0,他引:1
S Pavlovsky M Maschio M T Santarelli F S Muriel C Corrado I Garcia L Schwartz C Montero F L Sanahuja O Magnasco 《Journal of the National Cancer Institute》1988,80(18):1466-1473
A total of 277 patients with untreated Hodgkin's disease, clinical stages I-II, were randomized to cyclophosphamide, vinblastine, procarbazine, and prednisone (CVPP) alone for 6 monthly cycles or to CVPP plus radiation therapy (RT), 3,000 rad, to involved areas (CVPP plus RT). One or more of the following factors were considered as unfavorable prognosis: age greater than 45 years, more than two lymph node areas involved, or bulky disease. In the favorable group, disease-free survival (77% vs. 70%) or overall survival (92% vs. 91%) at 84 months for CVPP versus RT plus CVPP was similar. Patients with unfavorable prognosis treated with RT plus CVPP had longer disease-free survival (75% vs. 34%) (P = .001) and overall survival (84% vs. 66%) than patients treated with CVPP alone. 相似文献
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A revision of criteria for diagnosis of asbestos-related pathological conditions was performed studying specially asbestosis, pleural plaques and malignant mesothelioma, also taking into account the problems connected with histopathology. As regards the histological diagnosis of asbestosis, it requires the presence of diffuse interstitialfibrosis in a well inflated tissue remote from the site of a tumour or other large lesion, plus the presence of two or more asbestos bodies in a 1 cm2 section. As regards the imaging diagnosis, the HRTC 4-point scale proposed by Paris et al. (2004) has been adopted:--0 images not suggestive of interstitial pneumonia;--1 modest unilateral or bilateral interstitial abnormalities, involving restricted areas if bilateral;--2 interstitial abnormalities of limited extent, but consistent with a diagnosis of asbestosis, i.e. honeycombing, even without other parenchymal changes and even though unilateral, or else any two abnormal findings among thickened interlobular septa, intralobular lines or subpleural curved lines;--3 numerous bilateral changes on several slices involving more than 2/3 of the posterior third of each hemi thorax. Only points 2 and 3 were considered consistent with the diagnosis of lung fibrosis. Such HRCT findings are not specific for asbestosis, changes in the pleural wall such as diffuse plaques and thickenings contribute to the diagnosis of asbestosis. As regards the pleural plaques and asbestos bodies we remark that they are merely exposition markers. We also discussed the problems the pathologist may encounter in diagnosing mesothelioma; in this field the prospects are encouraging as microarray analysis are beginning to identify new molecular markers for mesothelioma. 相似文献
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