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11.
Fabian Doerr Akmal M. A. Badreldin Ferzen Can Ole Bayer Thorsten Wahlers 《Scandinavian cardiovascular journal : SCJ》2014,48(2):111-119
Objectives. Cardiac surgery patients are excluded from SAPS2 but included in SAPS3. Neither score is evaluated for this exclusive population; however, they are used daily. We hypothesized that SAPS3 may be superior to SAPS2 in outcome prediction in cardiac surgery patients. Design. All consecutive patients undergoing cardiac surgery between January 2007 and December 2010 were included in our prospective study. Both models were tested with calibration and discrimination statistics. We compared the AUC of the ROC curves by DeLong's method and calculated OCC values. Results. A total of 5207 patients with mean age of 67.2 ± 10.9 years were admitted to the ICU. The mean length of ICU stay was 4.6 ± 7.0 days and the ICU mortality was 5.9%. The two tested models had acceptable discriminatory power (AUC: SAPS2: 0.777–0.875; SAPS3: 0.757–893). SAPS3 had a low AUC and poor calibration on admission day. SAPS2 had poor calibration on Days 1–6 and 8. Conclusions. Despite including cardiac surgery patients, SAPS3 was not superior to SAPS2 in our analysis. In this large cohort of ICU cardiac surgery patients, performance of both SAPS models was generally poor. In this subset of patients, neither scoring system is recommended. 相似文献
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Templeton AW; Johnson JA; Anderson WH; Cook LT; Dwyer SJ d; Preston DF; Lee KR; Rosenthal SJ; Batnitzky S; Levine E 《Radiology》1984,151(2):527-528
The increasing use of digitally formatted imaging systems requires high-quality interactive gray-scale computer raster graphics systems for the management, display, and analog film recording of digital image and alphanumeric information. These systems are a combination of computer hardware and software and implement a set of graphics protocols. This paper describes a set of interactive graphics protocols that has been developed for clinical use. 相似文献
14.
Immunohistochemical localization of membrane and alpha-granule proteins in human megakaryocytes: application to plastic-embedded bone marrow biopsy specimens 总被引:12,自引:2,他引:12
Using a new technique for antigen localization, we have demonstrated platelet proteins in megakaryocytes in plastic-embedded biopsy specimens of normal human bone marrow. In a series of 25 specimens, megakaryocytes showed labeling with antibodies to the integral membrane glycoproteins IIIa, IIb, and the IIb-IIIa complex; granule membrane protein 140; and five alpha-granule matrix proteins: thrombospondin, factor VIII-related antigen, beta-thromboglobulin, platelet factor 4, and fibrinogen. The antibodies to the membrane glycoproteins IIIa, IIb, and IIb-IIIa produced diffuse cytoplasmic staining and heavier staining on the plasma membrane, whereas the antibodies to the alpha-granule matrix proteins produced a distinct granular staining within the cytoplasm. Staining for granule membrane protein 140 was also granular in distribution. Rare mononuclear cells consistent with megakaryocyte precursors were labeled with these markers. Other enzyme histochemical and lectin-binding studies showed that the enzyme alpha-naphthyl acetate esterase, the lectin Ulex europaeus I, and the periodic-acid Schiff reaction were consistent, but not specific, markers of megakaryocytes. This immunohistochemical technique should facilitate the examination of qualitative and quantitative changes in megakaryocytes in a variety of physiologic and pathologic processes. 相似文献
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Infection with the SARS-associated coronavirus (SARS-CoV) induces an atypical pulmonary disease with a high lethality rate. Although the initial SARS epidemic was contained, sporadic outbreaks of the disease still occur, suggesting a continuous need for a vaccine against this virus. We therefore explored exosome-based vaccines containing the spike S proteins of SARS-CoV. S-containing exosomes were obtained by replacing the transmembrane and cytoplasmic domains of the S protein by those of VSV-G. The immunogenicity and efficacy of the S-containing exosomes were tested in mice and compared to an adenoviral vector vaccine expressing the S protein. Both, S-containing exosomes and the adenoviral vector vaccine induced neutralizing antibody titers. After priming with the SARS-S exosomal vaccine and boosting with the adenoviral vector the neutralizing antibody titers exceeded those observed in the convalescent serum of a SARS patient. Both approaches were effective in a SARS-S-expressing tumor challenge model and thus warrant further investigation. 相似文献
19.
Zenker M Horn D Wieczorek D Allanson J Pauli S van der Burgt I Doerr HG Gaspar H Hofbeck M Gillessen-Kaesbach G Koch A Meinecke P Mundlos S Nowka A Rauch A Reif S von Schnakenburg C Seidel H Wehner LE Zweier C Bauhuber S Matejas V Kratz CP Thomas C Kutsche K 《Journal of medical genetics》2007,44(10):651-656
Background
Heterozygous gain‐of‐function mutations in various genes encoding proteins of the Ras‐MAPK signalling cascade have been identified as the genetic basis of Noonan syndrome (NS) and cardio‐facio‐cutaneous syndrome (CFCS). Mutations of SOS1, the gene encoding a guanine nucleotide exchange factor for Ras, have been the most recent discoveries in patients with NS, but this gene has not been studied in patients with CFCS.Methods and results
We investigated SOS1 in a large cohort of patients with disorders of the NS–CFCS spectrum, who had previously tested negative for mutations in PTPN11, KRAS, BRAF, MEK1 and MEK2. Missense mutations of SOS1 were discovered in 28% of patients with NS. In contrast, none of the patients classified as having CFCS was found to carry a pathogenic sequence change in this gene.Conclusion
We have confirmed SOS1 as the second major gene for NS. Patients carrying mutations in this gene have a distinctive phenotype with frequent ectodermal anomalies such as keratosis pilaris and curly hair. However, the clinical picture associated with SOS1 mutations is different from that of CFCS. These findings corroborate that, despite being caused by gain‐of‐function mutations in molecules belonging to the same pathway, NS and CFCS scarcely overlap genotypically. 相似文献20.
Zusammenfassung
Bei einer 37 j?hrigen, bisher gesunden Patientin entwickelte sich eine über 2 Monate progrediente Dyspnoe. Radiologisch und
echokardiographisch zeigte sich eine massive Dilatation s?mtlicher Herzh?hlen mit biventrikul?ren Thromben und eine stark
herabgesetzte Kontraktilit?t. Die Endomyokardbiopsien wurden von 2 Instituten als Myokarditis eingestuft. Im weiteren Verlauf
entwickelten sich thrombembolische Komplikationen und ein therapierefrakt?res Pumpversagen, in dem die Patientin schlie?lich
verstarb. Bei der Obduktion fand sich au?er einem dilatierten 600 g schweren Herzen mit biventrikul?ren Thromben ein klinisch
bisher unbekanntes Ph?ochromozytom der linken Nebenniere. Die eingehende histologische und immunhistologische Aufarbeitung
des Herzmuskelgewebes einschlie?lich Reevaluierung der Endomyokardbiopsien führte zur Revision der ursprünglichen Diagnose:
Das Krankheitsbild der 37 j?hrigen Patientin war durch eine katecholamininduzierte dilatative Kardiomyopathie verursacht worden.
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