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941.
AIM: To evaluate in a multicenter study whether the sonographic characterization of focal liver lesions can be improved using SonoVue(R)-enhancement; and to compare this method with computed tomography (CT) and magnetic resonance imaging (MRI). METHODS: One hundred and thirty four patients with one focal liver lesion detected in baseline ultrasound (US) were examined with conventional US, contrastenhanced US ( n = 134), contrast-enhanced CT ( n = 115) and/or dynamic contrast-enhanced MRI ( n = 70). The lesions were classified as malignant, benign or indeterminate and the type of lesion was determined.The final diagnosis based on the combined information of all imaging examinations, clinical information and histology ( n = 32) was used. Comparisons were made to see whether the addition of contrast-enhanced US led to the improvement of the characterization of doubtful focal liver lesions. RESULTS: In comparison with unenhanced US, SonoVue(r) markedly improves sensitivity and specificity for the characterization (malignant/benign) of focal liver lesions. In comparison with CT and/or dynamic MRI, SonoVue(r) -enhanced sonography applied for characterization of focal liver lesions was 30.2% more sensitive in the recognition of malignancy and 16.1% more specific in the exclusion of malignancy and overall 22.9% more accurate. In the subgroup with confirmative histology available ( n = 30), sensitivity was 95.5% (CEUS), 72.2% (CT) and 81.8% (MRI), and specificity was 75.0% (CEUS), 37.5% (CT) and 42.9% (MRI). The sensitivity and specificity of CEUS for the identification of focal nodular hyperplasia (FNH) and hemangiomas was 100% and 87%, resulting in an accuracy of 94.5%. CONCLUSION: SonoVue(r)-enhanced sonography emerges as the most sensitive, most specific and thus most accurate imaging modality for the characterization of focal liver lesions. 相似文献
942.
Miriam Hauben Boris Haesendonckx Evi Standaert Katrien Van Der Kelen Abdelkrim Azmi Hervé Akpo Frank Van Breusegem Yves Guisez Marc Bots Bart Lambert Benjamin Laga Marc De Block 《Proceedings of the National Academy of Sciences of the United States of America》2009,106(47):20109-20114
Quantitative traits, such as size and weight in animals and seed yield in plants, are distributed normally, even within a population of genetically identical individuals. For example, in plants, various factors, such as local soil quality, microclimate, and sowing depth, affect growth differences among individual plants of isogenic populations. Besides these physical factors, also epigenetic components contribute to differences in growth and yield. The network that regulates crop yield is still not well understood. Although this network is expected to have epigenetic elements, it is completely unclear whether it would be possible to shape the epigenome to increase crop yield. Here we show that energy use efficiency is an important factor in determining seed yield in canola (Brassica napus) and that it can be selected artificially through an epigenetic feature. From an isogenic canola population of which the individual plants and their self-fertilized progenies were recursively selected for respiration intensity, populations with distinct physiological and agronomical characteristics could be generated. These populations were found to be genetically identical, but epigenetically different. Furthermore, both the DNA methylation patterns as well as the agronomical and physiological characteristics of the selected lines were heritable. Hybrids derived from parent lines selected for high energy use efficiencies had a 5% yield increase on top of heterosis. Our results demonstrate that artificial selection allows the increase of the yield potential by selecting populations with particular epigenomic states. 相似文献
943.
The objective of this study was to assess whether parameters of the negative expiratory pressure (NEP) technique are able to detect obstructive sleep apnea syndrome (OSAS) in snoring patients. A cross-sectional study included 42 OSAS patients diagnosed by polysomnography (PSG), 34 simple snorers, and 32 healthy subjects. Lung function was measured by using a plethysmograph and the NEP technique was performed with the patient in the seated and supine positions in a random order. The depression was fixed to 5 cmH(2)O. All patients had normal forced expiratory flow/volume loops. Apneic patients had lower Dflow in both positions with a number of oscillations on the expiratory curve obtained with NEP and an expiratory flow limitation (EFL) in the supine position higher than that of other groups (p < 0.05). Changing from the sitting to the supine position raised the EFL of the three groups, with a significant decrease in Dflow and an increase in the number of oscillations in snoring and OSAS patients (p < 0.05). The analysis of variance showed that only the number of oscillations was significantly different between apneic and snoring patients. NEP constitutes a simple and useful tool for the screening OSAS by EFL, especially the number of oscillations obtained with NEP. 相似文献
944.
945.
Judith Raimbourg Grégoire Cormier Gilles Tanguy Yves Bleher Hervé Maisonneuve 《Joint, bone, spine : revue du rhumatisme》2009,76(4):416-420
Hairy-cell leukemia is a chronic B-cell malignancy seen in adults. The presenting manifestations consist of splenomegaly, pancytopenia, and characteristic monocyte depletion. The presence in peripheral blood or bone marrow of hairy cells exhibiting the CD19+ CD20+ CD25+ CD11c+ phenotype establishes the diagnosis. Rarely, patients present with inaugural joint manifestations related either to the hematological malignancy or to immune dysfunction. The resulting polymorphic polyarticular symptoms may cause diagnostic wanderings. Monocytopenia is a valuable diagnostic clue. The identification of hairy cells in the joint fluid establishes the diagnosis of leukemia-related arthritis. The treatment rests on purine analogs. One of the main differential diagnoses is Felty's syndrome, which combines rheumatoid arthritis, splenomegaly, and neutropenia. Felty's syndrome is usually caused by T-cell lymphoproliferative disorders. Among 27 patients with hairy-cell leukemia managed at our institution, 1 presented with joint manifestations. We describe this case. 相似文献
946.
Paulette Bioulac‐Sage Hervé Laumonier Anne Rullier Gaelle Cubel Christophe Laurent Jessica Zucman‐Rossi Charles Balabaud 《Liver international》2009,29(3):459-465
Background and Aims: Glutamine synthetase (GS) is a useful marker in tumour liver pathology, including hepatocellular adenomas and nodules in cirrhosis. We investigated the use of GS as a marker in various clinical situations, in which FNH diagnosis had been firmly established to determine its contribution to diagnosis. Methods: Seventy‐nine cases of resected FNH, all on normal (or occasionally steatotic) livers, were retrieved from our collection. The control group was composed of hepatocellular adenomas and well‐differentiated hepatocellular carcinoma. The following stains: H&E, Masson's trichrome, Gordon‐Sweet, PAS, perls and immunostains: CK7 and 19, and GS were carried out. FNH was diagnosed based on traditional pathological techniques. In case of uncertainty, particularly with hepatocellular adenoma, additional immunostainings including liver fatty acid‐binding protein, serum amyloid A and β‐catenin were performed. Results: Glutamine synthetase immunostaining was similar in all FNH cases. Positive GS staining of hepatocytic cytoplasms formed large areas, anastomosed in a ‘map‐like’ pattern, often surrounding hepatic veins, whereas GS was not expressed in hepatocytes close to fibrotic bands containing arteries and ductules. In comparison, hepatocellular adenoma staining was completely different, even in cases of fibrotic bands due to tumour remodelling related to necrosis or haemorrhage. In hepatocellular adenomas or well‐differentiated hepatocellular carcinoma presenting β‐catenin mutation, GS was positive but with a completely different pattern that appeared diffuse and not ‘map‐like’. Conclusion: Regardless of the FNH size or steatotic content, GS produced a similar and characteristic pattern and consequently represents a good marker for easily identifying resected FNH from other hepatocellular nodules. 相似文献
947.
Asunción Hervás Morón María Luisa García de Paredes Eduardo Lobo Martínez 《Clinical & translational oncology》2010,12(12):805-818
The treatment of rectal cancer has evolved over the last few decades from surgery alone to treatments with trimodal therapy for high-risk patients. The involvement of a multidisciplinary team of radiologists, pathologists, surgeons, radiotherapists and medical oncologists is now fundamental for decision-making and outcomes. The evolution of different diagnostic and therapeutic techniques has optimised the therapeutic rate. Future studies will determine the optimal regimen for inducing complete responses in locally advanced disease and whether the intensification of local treatments could enable the use of more conservative treatments, as for other tumour locations. The study of biomarkers will be essential in this respect. 相似文献
948.
Joaquín Martí María C. Santa-Cruz Roger Serra Oliver Valero Vanessa Molina José P. Hervás Sandra Villegas 《Cerebellum (London, England)》2013,12(3):406-417
The present study evaluates the usefulness of the principal component analysis-based cluster analysis in the categorization of several sub-phenotypes in the weaver mutant by using several morphological parameters from the cerebellar cortex of control, heterozygous (+/wv) and homozygous (wv/wv) weaver mice. The quantified parameters were length of the cerebellar cortex, area of the external granular layer, area of the molecular layer, number of the external granular layer cells (EGL), and number of Purkinje cells (PCs). The analysis indicated that at postnatal day 8, the genotype +/wv presented three sub-phenotypes tagged as +/wv 0, +/wv 1 and +/wv 2, whereas two sub-phenotypes designated as wv 0/wv 1 and wv 0/wv 2 were identified in the genotype wv/wv. The number of PCs for the genotype +/wv and the number of EGL cells for the genotype wv/wv were the variables that discriminated the best among sub-phenotypes. Each one of the sub-phenotypes showed specific abnormalities in the cytoarchitecture of the cerebellar cortex as well as in the foliar pattern. In particular, the wv 0/wv 1 and wv 0/wv 2 sub-phenotypes had the most altered cytoarchitectonics, followed by the +/wv 2 sub-phenotype and then by the +/wv 1 one. The sub-phenotype +/wv 0 was the less affected one. Apart from reporting for the first time the coexistence of several sub-phenotypes in the weaver mutant, our approach provides a new statistical tool that can be used to assess cerebellar morphology. 相似文献
949.
950.
Jaime Ruiz-Tovar Vicente Morales Asunción Hervás Alfonso Sanjuanbenito Eduardo Lobo Enrique Martínez-Molina 《Clinical & translational oncology》2009,11(8):539-543