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61.
Czarniak E Samet A Bronk M Rybak B Kochowska-Bronk M Zajac-Lenczewska I Ksiazek J Skokowski J 《Pneumonologia i alergologia polska》2003,71(1-2):31-35
The clinical specimens received from patients hospitalized in Department of Thoracic Surgery between 1997 and 2001 were microbiologically examined. The main specimen for microbiological examination was pleural fluid (median 34%). The frequency of specimens from bronchial tree increased significantly (from 4% to 26%) with concurrent decrease of sputum (from 29% to 6%). Among isolated pathogens, Gram negative rods were the most frequent (median 48%) and Pseudomonas sp. was the main pathogen among them. Occurrence of staphylococci was median 22% and Staphylococcus aureus, with a little decrease in analyzed period, was still the main Gram positive pathogen. Simultaneously the occurrence of MRSA in the last three years dropped three times. The number of isolations of yeasts have risen from 5.8% to 10.3%. 相似文献
62.
Incidence and determinants of moderate COPD (GOLD II) in male smokers aged 40–65 years: 5-year follow up
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Roeland MM Geijer Alfred PE Sachs Theo JM Verheij Philippe L Salom Jan-Willem J Lammers Arno W Hoes 《The British journal of general practice》2006,56(530):656-661
BACKGROUND: Chronic obstructive pulmonary disease (COPD) is a major health problem with an estimated prevalence of 10-15% among smokers. The incidence of moderate COPD, as defined by the Global Initiative for Chronic Obstructive Lung Disease (GOLD), is largely unknown. AIM: To determine the cumulative incidence of moderate COPD (forced expiratory volume in 1 second/forced vital capacity ratio [FEV1/FVC] <0.7 and FEV1 <80% predicted) and its association with patient characteristics in a cohort of male smokers. DESIGN: Prospective cohort study. SETTING: The city of IJsselstein, a small town in the Netherlands. METHOD: Smokers aged 40-65 years who were registered with local GPs, participated in a study to identify undetected COPD. Baseline measurements were taken in 1998 of 399 smokers with normal spirometry (n = 292) or mild COPD (FEV1/FVC <0.7 and FEV1 >or=80% predicted, n = 107) and follow-up measurements were conducted in 2003. RESULTS: After a mean follow-up of 5.2 years, 33 participants developed moderate COPD (GOLD II). This showed an estimated cumulative incidence of 8.3% (95% CI = 5.8 to 11.4) and a mean annual incidence of 1.6%. No participant developed severe airflow obstruction. The risk of developing moderate COPD in smokers with baseline mild COPD (GOLD I) was five times higher than in those with baseline normal spirometry (one in five versus one in 25). CONCLUSIONS: In a cohort of middle-aged male smokers, the estimated cumulative incidence of moderate COPD (GOLD II) over 5 years was relatively high (8.3%). Age, childhood smoking, cough, and one or more GP contacts for lower respiratory tract problems were independently associated with incident moderate COPD. 相似文献
63.
Matthew J. Bassignani Samuel J. Dwyer III Jonathan M. Ciambotti Juan M Olazagasti Ruth Moran Sean Moynihan Alfred C. Weaver Andrew M. Snyder 《Journal of digital imaging》2004,17(1):18-27
Teleradiology allows contemporaneous interpretation of imaging exams performed at some distance from the interpreting radiologist. The transmitted images are usually static. However, there is benefit to real-time review of full-motion ultrasound (US) exams as they are performed. Telesonography is transmission of full-motion sonographic data to a remote site. We hypothesize that US exams, read after having been compressed utilizing Motion Picture Experts Group version 4 (MPEG-4) compression scheme, transmitted over the Internet as streaming multimedia, decompressed, and displayed, are equivalent in diagnostic accuracy to reading the examinations locally. MPEG-4 uses variable compression on each image frame to achieve a constant output bit rate. With less compression, the bit rate rises, and the only way the encoder can contain bit rate within the set bandwidth is by lowering frame rate or reducing image quality. We review the relevant technologies and industry standard components that will enable low-cost telesonography. 相似文献
64.
Chest radiography in general practice: indications, diagnostic yield and consequences for patient management
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Anouk M Speets Yolanda van der Graaf Arno W Hoes Sandra Kalmijn Alfred PE Sachs Matthieu JCM Rutten Jan Willem C Gratama Alexander D Montauban van Swijndregt Willem PThM Mali 《The British journal of general practice》2006,56(529):574-578
BACKGROUND: Chest radiography (CXR) is frequently performed in Western societies. There is insufficient knowledge of its diagnostic value in terms of changes in patient management decisions in primary care. AIM: To assess the influence of CXR on patient management in general practice. DESIGN OF STUDY: Prospective cohort study. SETTING: Seventy-eight GPs and three general hospitals in the Netherlands. METHOD: Patients (n = 792) aged > or =18 years referred by their GPs for CXR were included. The main outcome was change in patient management assessed by means of questionnaires filled in by GPs before and after CXR. RESULTS: Mean age of the patients was 57.3+/-16.2 years and 53% were male. Clinically relevant abnormalities were found in 24% of the CXRs. Patient management changed in 60% of the patients following CXR. Main changes included: fewer referrals to a medical specialist (from 26 to 12%); reduction in initiation or change in therapy (from 24 to 15%); and more frequent reassurance (from 25 to 46%). However, this reassurance was not perceived as such in a quarter of these patients. A change in patient management occurred significantly more frequently in patients with complaints of cough (67%), those who exhibited abnormalities during physical examination (69%), or those with a suspected diagnosis of pneumonia (68%). CONCLUSION: Patient management by the GP changed in 60% of patients following CXR. CXR substantially reduced the number of referrals and initiation or change in therapy, and more patients were reassured by their GP. Thus, CXR is an important diagnostic tool for GPs and seems a cost-effective diagnostic test. 相似文献
65.
cDNA arrays are a powerful tool for the identification of differentially expressed genes in malignant tumors. We used this technique to study the gene expression profiles of anaplastic large cell lymphoma (ALCL) and Hodgkin's disease (HD). Gene expression of 11 lymphoma cell lines was analyzed covering 1176 cDNA sequences. Comparing these data to the expression profiles of B- and T-lymphocytes, we identified 27 genes that were deregulated in all cell lines or in a particular entity. For the establishment of gene expression profiles the 27 genes were assigned to four groups composed of genes deregulated in (i) all lymphoma cell lines, (ii) ALCL and HD, (iii) only HD, and (iv) ALCL exclusively. Our results indicate that ALCL and HD share the differential expression of at least five genes. In addition, both entities are characterized by the differentially deregulated expression of four genes in HD and seven genes in ALCL. Because the expression profiling was performed on cell lines, further studies are needed to clarify the biological significance of the differentially expressed genes. 相似文献
66.
Wassif CA Krakowiak PA Wright BS Gewandter JS Sterner AL Javitt N Yergey AL Porter FD 《Molecular genetics and metabolism》2005,85(2):96-107
Smith-Lemli-Opitz syndrome (RSH/SLOS) is an autosomal recessive, malformation syndrome caused by mutations in the 3beta-hydroxysterol delta7-reductase gene (DHCR7). DHCR7 catalyzes the reduction of 7-dehydrocholesterol (7DHC) to cholesterol. We report the mutation analysis and determination of residual cholesterol synthesis in 47 SLOS patients, and the effects of treatment of SLOS skin fibroblasts with simvastatin. Using deuterium labeling we have quantified the amount of synthesized cholesterol and 7DHC in homozygote, heterozygote, and control fibroblast cell lines. In SLOS fibroblasts, the fraction of synthesized cholesterol to total sterol synthesis ranged from undetectable to over 50%. This establishes that different mutant alleles encode enzymes with varying degrees of residual activity. There was a correlation between increased phenotypic severity and decreased residual cholesterol synthesis (r(2)=0.45, p<0.0001). Simvastatin treatment of SLOS fibroblasts with residual DHCR7 enzymatic activity decreased 7DHC levels and increased cholesterol synthesis. This increase in cholesterol synthesis is due to increased expression of a mutant allele with residual function. Determination of residual enzymatic activity for specific DHCR7 mutant alleles will help in understanding the processes underlying the broad phenotypic spectrum found in this disorder and will be useful in identifying patients who may benefit from simvastatin therapy. 相似文献
67.
The Effect of Thorotrast® and Cortisone on Renal Cortical Fibrinolytic Activity in the Rabbit
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Previous studies have shown that a single injection of endotoxin inhibits renal cortical fibrinolytic activity in the rabbit. This suggests that the initial injection of endotoxin may prepare for the generalized Shwartzman reaction by depletion of cortical fibrinolytic activity. A fibrin slide technic was used to determine whether Thorotrast® and cortisone prepare for the generalized Schwartzman reaction by a similar mechanism. Renal cortical fibrinolytic activity was inhibited following Thorotrast injection, but no inhibition could be detected following cortisone injection. This suggests that Thorotrast, like endotoxin, prepares for the generalized Shwartzman reaction by depletion of cortical fibrinolytic activity. Failure to demonstrate inhibition of lytic activity following cortisone injection may indicate that cortisone prepares for the generalized Shwartzman reaction by another mechanism, or that the fibrin slide technic was unable to detect quantitative changes in lytic activity. 相似文献
68.
69.
Generation, annotation, evolutionary analysis, and database integration of 20,000 unique sea urchin EST clusters 总被引:2,自引:0,他引:2
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Poustka AJ Groth D Hennig S Thamm S Cameron A Beck A Reinhardt R Herwig R Panopoulou G Lehrach H 《Genome research》2003,13(12):2736-2746
Together with the hemichordates, sea urchins represent basal groups of nonchordate invertebrate deuterostomes that occupy a key position in bilaterian evolution. Because sea urchin embryos are also amenable to functional studies, the sea urchin system has emerged as one of the leading models for the analysis of the function of genomic regulatory networks that control development. We have analyzed a total of 107,283 cDNA clones of libraries that span the development of the sea urchin Strongylocentrotus purpuratus. Normalization by oligonucleotide fingerprinting, EST sequencing and sequence clustering resulted in an EST catalog comprised of 20,000 unique genes or gene fragments. Around 7000 of the unique EST consensus sequences were associated with molecular and developmental functions. Phylogenetic comparison of the identified genes to the genome of the urochordate Ciona intestinalis indicate that at least one quarter of the genes thought to be chordate specific were already present at the base of deuterostome evolution. Comparison of the number of gene copies in sea urchins to those in chordates and vertebrates indicates that the sea urchin genome has not undergone extensive gene or complete genome duplications. The established unique gene set represents an essential tool for the annotation and assembly of the forthcoming sea urchin genome sequence. All cDNA clones and filters of all analyzed libraries are available from the resource center of the German genome project at http://www.rzpd.de. 相似文献
70.
In recent years, medical educators have expressed concern that the reductionist-positivist mode of medical education fails to equip physicians with the skills and attitudes to meet the full range of patients' physical and emotional needs. Indeed, the authors suggest that neither patients nor physicians are satisfied. Among the factors responsible are a pervasive industrialization of clinical practice, a progressive segmentation of patient care, and a deepening shortage of both primary care and specialty physicians. But underlying these system issues is a lack of adequate schooling in the values, ethics, and culture of caring. Today's physicians must simultaneously be analytical, perceptive, and self-reflective. They must have the capacity to see their patients as individuals with differing psychological, social, and historical natures. And they must have insight into their own values and behaviors. All of this contributes to making a competent and humane physician. To aid medical students in achieving these characteristics, the authors contend that medical education must be radically restructured so that knowledge and skills are taught within the context of values and ethics. This commentary explores such reform through the lens of three articles published in the current issue of Academic Medicine, by Litzelman and Cottingham, Kanter and colleagues, and Dobie. These articles are the product of a national call that resulted in more than thirty abstracts, testimony to the fertile thinking already being applied to this problem. It is the authors' hope that this series of papers will stimulate still more thinking and lead to the curricular reform that future generations of physicians deserve. 相似文献