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991.
Biologic correlates of (18)fluorodeoxyglucose uptake in human breast cancer measured by positron emission tomography. 总被引:32,自引:0,他引:32
Reinhard Bos Jacobus J M van Der Hoeven Elsken van Der Wall Petra van Der Groep Paul J van Diest Emile F I Comans Urvi Joshi Gregg L Semenza Otto S Hoekstra Adriaan A Lammertsma Carla F M Molthoff 《Journal of clinical oncology》2002,20(2):379-387
PURPOSE: Variable uptake of the glucose analog (18)fluorodeoxyglucose (FDG) has been noticed in positron emission tomography (PET) studies of breast cancer patients, with low uptake occurring especially in lobular cancer. At present, no satisfactory biologic explanation exists for this phenomenon. This study compared (18)FDG uptake in vivo with biomarkers expected to be involved in the underlying biologic mechanisms. PATIENTS AND METHODS: Preoperative (18)FDG-PET scans were performed in 55 patients. (18)FDG activity was assessed visually by three observers using a four-point score. Tumor sections were stained by immunohistochemistry for glucose transporter-1 (Glut-1); Hexokinase (HK) I, II, and III; macrophages; hypoxia-inducible factor-1-alfa (HIF-1alpha); vascular endothelial growth factor (VEGF(165)); and microvessels. Mitotic activity index (MAI), amount of necrosis, number of lymphocytes, and tumor cells/volume were assessed. RESULTS: There were positive correlations between (18)FDG uptake and Glut-1 expression (P <.001), MAI (P =.001), amount of necrosis (P =.010), number of tumor cells/volume (P =.009), expression of HK I (P =.019), number of lymphocytes (P =.032), and microvessel density (r =.373; P =.005). HIF-1alpha, VEGF(165), HK II, HK III, and macrophages showed no univariate correlation with (18)FDG. In logistic regression, however, HIF-1alpha and HK II added value to MAI and Glut-1. CONCLUSION: (18)FDG uptake in breast cancer is a function of microvasculature for delivering nutrients, Glut-1 for transportation of (18)FDG into the cell, HK for entering (18)FDG into glycolysis, number of tumor cells/volume, proliferation rate (also reflected in necrosis), number of lymphocytes (not macrophages), and HIF-1alpha for upregulating Glut-1. Together, these features explain why breast cancers vary in (18)FDG uptake and elucidate the low uptake in lobular breast cancer. 相似文献
992.
Roland A. M. J. Claessens Otto C. Boerman Emile B. Koenders Wim J. G. Oyen Jos W. M. van der Meer Frans H. M. Corstens 《European journal of nuclear medicine and molecular imaging》1996,23(4):414-421
Recently a new linker — hydrazinonicotinate (HYNIC) — was introduced for labelling of proteins and peptides with technetium-99m. HYNIC and other linkers have been used for labelling of human non-specific polyclonal immunoglobulin G (hIgG) with99mTc for the detection of infections. In this study we compared the tissue distribution of three different99mTc-hIgG preparations in groups of five Wistar rats with a focal intramuscular infection withStaphylococcus aureus. We compared99mTc-HYNIC-hIgG with99mTc-hIgG labelled via the so-called Schwarz method (reduction of disulphide bonds) and with the99mTc-labelled commercially available Technescan-HIG. Unlike the HYNIC linker, in the two other labelling methods free sulph-hydryl groups are involved in the binding of99mTc. High-performance liquid chromatography analysis of the labelled preparations and of plasma samples revealed aggregate or polymer formation in all three agents; this was least pronounced in the product labelled by means of the Schwarz method. The tested preparations did not show signs of degradation in vitro. The difference in linker chemistry was reflected in the tissue distribution. Thus the biodistribution of99mTc-HYNIC-hIgG was significantly different from the distribution of the two other preparations: abscess (1.4%±0.2%ID/g), muscle, liver, spleen, plasma, lung, bone marrow, and small intestine concentrations were higher at 24 h p.i.; kidney uptake (1.19%±0.08%ID/g) was significantly lower. The abscess-to-plasma and the abscess-to-muscle ratios (0.5 and 11, respectively), however, were in the same range for the three preparations tested. Quantitative analysis of the scintigraphs revealed that the total body clearance of99mTc-HYNIC-hIgG was significantly slower than for the other agents. The abscess uptake of99mTc-HYNIC-hIgG as a percentage of the remaining body activity was significantly higher. Based on its high abscess uptake, its low uptake in the kidneys and the high percentage of its abscess uptake in relation to the remaining body activity, we conclude that99mTc-HYNIC-hIgG seems superior to the two other preparations tested for the detection of infections. 相似文献
993.
994.
995.
Carcinomatous involvement of the hilum and mediastinum: computed tomographic and magnetic resonance evaluation 总被引:1,自引:0,他引:1
Heelan RT; Martini N; Westcott JW; Bains MS; Watson RC; Caravelli JF; Berkmen YM; Henschke CI; McCormack PM; McCaughan BC 《Radiology》1985,156(1):111-115
Magnetic resonance (MR) imaging and computed tomography (CT) were compared in 20 patients who had primary lung tumors, and the results were correlated with findings at surgery and pathologic evaluation. Both studies demonstrated a similar ability to detect hilar and mediastinal tumor. MR imaging detected more enlarged nodes in the mediastinum, but in several patients these enlarged nodes did not contain tumor. Consequently, MR imaging has a slightly higher false-positive rate in the evaluation of the mediastinum. Both modalities were highly sensitive, with specificity limited by the presence of enlarged benign lymph nodes in this series of patients. 相似文献
996.
Florence Lagarde Lonard Reibel Emile Franta 《Macromolecular chemistry and physics.》1992,193(5):1087-1097
The early stage of cationic polymerization of 1,2-epoxy-3-nitropropane in the presence of ethylene glycol and borontrifluoride etherate is examined. It is shown that the reaction proceeds according to the Activated Monomer Mechanism: initiation and propagation involve the nucleophilic attack of an hydroxyl end-group moiety onto a protonated monomer molecule; this attack takes place on the carbon atom located in the β-position with regard to the ? CH2NO2 group. 相似文献
997.
Biochemical evidence for altered subchondral bone collagen metabolism in osteoarthritis of the hip 总被引:3,自引:0,他引:3
Osteoarthritis (OA) of the hip is invariably viewed as a disease primarily
affecting the articular cartilage. Data presented in this report, however,
demonstrate changes in the metabolic activity of the underlying trabecular
bone tissue, the processes of which may represent a significant factor in
the pathogenesis of hip OA. Trabecular bone tissue from OA subjects
expressed significantly more matrix metalloproteinase (MMP)-2 (gelatinase
A, 72 kDa type IV collagenase) when compared to age-matched osteoporotic
(OP) and normal bone tissue. Alkaline phosphatase was also significantly
elevated in OA bone tissue. The combination of increased MMP-2 and alkaline
phosphatase indicates heightened collagen turnover in the subchondral bone
compartment of osteoarthritic hips. The data obtained from this study
warrant a closer investigation into the significance of these changes in OA
and emphasize the multifactorial elements of the whole joint in the whole
joint in the overall disease process.
相似文献
998.
A monoclonal antibody (LYP18) directed against the blood platelet glycoprotein IIb/IIIa complex inhibits human melanoma growth in vivo 总被引:7,自引:0,他引:7
A monoclonal antibody (MoAb) (LYP18), generated against human platelet glycoprotein IIb/IIIa (GPIIb/IIIa), immuno-precipitated a IIb/IIIa-like GP complex from a highly tumorigenic human melanoma cell line (M3Dau). The M3Dau melanoma cells specifically bound 125I-labeled LYP18. To study the biologic role of these IIb/IIIa-like glycoproteins, M3Dau melanoma cells were incubated with LYP18 or a control MoAb directed against another melanoma cell-surface antigen and implanted subcutaneously (SC) in nude mice. LYP18 dramatically inhibited the growth of tumor in vivo. LYP18 was not directly cytotoxic to the melanoma cells. These results demonstrate that the IIb/IIIa-like GPs are present on melanoma cells and play a crucial role in tumor cell growth. MoAbs directed against tumor cytoadhesive receptors may represent a novel approach in tumor treatment. 相似文献
999.
O Chassany D Elkharrat JF Bergmann JM Segrestaa 《La Revue de médecine interne / fondée ... par la Société nationale francaise de médecine interne》1995,16(12)
Gastroesophageal reflux is a common disease. Its chronic course, even if mild, is sometimes complicated by erosive oesophagitis. Drug therapy acts against gastric acidity and motility disorders. Treatment of gastroesophageal reflux disease has three aims: improvement of symptoms and quality of life, healing erosive lesions and prevention of symptomatic and endoscopie relapses. Non-drug measures are always useful, even if their efficacy is not well established. Initial therapy of a symptomatic reflux or mild oesophagitis is most of the time effective (antacids, prokinetics, H2 receptor antagonists). Proton-pump inhibitors are also effective in healing and preventing severe oesophagitis. Questions about long-term treatment adverse events with powerful acid inhibitors, such as hypergastrinemia and the risk of gastric carcinoid tumours seem to be resolved. Studies are requested to define the optimal long-term maintenance treatment with cisapride, H2 receptor antagonists or proton-pump inhibitors at low doses in prevention of symptomatic and mild oesophagitis relapses. 相似文献