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101.
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Enzyme activities of the serine/threonine kinase Akt were compared in mid-temporal and mid-frontal cortices from Alzheimer's disease cases and matched controls. Activities (GSK-3alpha/beta fusion protein phosphorylation by immunoprecipitated Akt) were significantly increased in temporal cortex soluble fractions from Alzheimer's disease compared with non-disease controls and positive disease controls with another neurodegenerative disease. Temporal cortex soluble fraction Akt activities positively correlated with Braak staging for neurofibrillary changes. Frontal cortex soluble fraction activities were significantly reduced in positive disease compared with Alzheimer's disease cases and non-disease controls. Strong Ser Akt immunoreactivity was seen in Alzheimer's disease pyramidal neurons likely undergoing degeneration and in reactive astroglia. Non-disease and positive disease controls showed moderate Ser Akt immunostaining of occasional pyramidal neurons. 相似文献
103.
Dalal I Binson I Levine A Somekh E Ballin A Reifen R 《Pediatric allergy and immunology》2003,14(4):312-316
Recently, we found sesame to be a major cause of severe IgE-mediated food allergic reactions among infants and young children in Israel. The purpose of this study was to describe the different patterns of sesame sensitivity. We have identified three subgroups among our patients (n = 32). Group I (n = 23, M/F; 14/9) consisted of cases with IgE-mediated sesame allergy. The mean age of the first allergic reaction was 11.7 months. Although the main clinical manifestation was urticaria/angiedema (n = 14, 60%), anaphylaxis was the presenting symptom in seven (30%) patients; all of them were younger than 1 year. Sixteen (70%) were found to be allergic to other foods, and other atopic diseases were identified in 18 (78%) patients. Three patients 'outgrew' their allergy within 1–2 years. Group II (n = 2) included cases in whom sesame allergy was ruled out based on a negative skin prick test (SPT) together with a negative open oral challenge. Group III (n = 7) consisted of patients that were found to be SPT positive for sesame as part of a screening for other food allergies. Although sesame products have become fashionable in westernized countries, early exposure may cause sesame to share eventually the same 'noteriety and fate' as peanut – a major cause of severe food allergic reactions. 相似文献
104.
Bergmann OJ Christiansen M Laursen I Bang P Hansen NE Ellegaard J Koch C Andersen V 《European journal of haematology》2003,70(2):91-97
PURPOSE: To estimate the clinical significance of low serum concentrations of mannose-binding lectin (MBL) in patients with acute myeloid leukaemia (AML) during initial cancer chemotherapy. PATIENTS AND METHODS: 80 consecutive, newly diagnosed, and unselected AML patients (age 18-77 yr) undergoing remission induction chemotherapy. The patients were examined for 28 d. MAIN FINDINGS: Low levels of serum MBL (<1,000 microg/L) were found in 16/80 patients at diagnosis. This frequency is similar to what is found in the general population. In the remaining 64 patients, MBL concentrations were significantly higher than in controls and showed only a slight rise during the period of antineoplastic chemotherapy with its associated infectious complications. Low levels of MBL did not affect overall survival or morbidity in terms of incidence or duration of fever, or occurrence of septicaemia or pneumonia. Long-term survival was likewise independent of MBL concentration. CONCLUSION: MBL levels have no discernible influence on the occurrence or course of infections in AML patients during the initial hospitalisation. The predominant immunodeficiency during this phase is the profound granulocytopenia, which also compromises important effector functions of MBL. The finding in most AML patients of elevated MBL concentrations on admission is most likely because of the role of MBL as an acute phase reactant. 相似文献
105.
Can particulate extraction from the ascending aorta reduce neurologic injury in cardiac surgery? 总被引:3,自引:0,他引:3
Schmitz C Weinreich S White J Oengoeren I Schneider R Schneider D Speth I Pohl C Welz A 《The Journal of thoracic and cardiovascular surgery》2003,126(6):1829-1838
OBJECTIVE: This study examined whether extraction of particulate emboli using intra-aortic filtration could decrease neurologic outcomes. METHODS: Patients (N = 582) were enrolled in a prospective, controlled study and alternately assigned to the therapy arm (n = 304; intra-aortic filtration) or control arm (n = 278). Preoperative, procedural, and postoperative data were collected. Neurologic examinations included the National Institutes of Health Stroke Scale, Glasgow Coma Scale, and memory tests. Investigators administering neurologic tests were blinded to the study arm. By the use of logistic regression and propensity matching, composite neurologic outcomes (transient ischemic attack, stroke, delirium, coma, and memory deficit) were evaluated. RESULTS: Patients in the filter group experienced a lower incidence of adverse neurologic outcomes than patients in the control group (4.3% vs 11.9%) (P <.001). There were significantly less transient ischemic attacks (0% vs 1.4%), delirium (3.0% vs 6.5%), and memory deficit (1.3% vs 6.2%). There were fewer strokes in the filter group compared with the control group (0.7% vs 2.2%), although the sample size was too small for a significant finding. Both groups experienced 1 coma outcome. The use of a filter was associated with an adjusted odds ratio of 0.375, implying that a patient who does not receive a filter is 2.7 times more likely to experience an adverse neurologic event. Logistic modeling also demonstrated that there are increasing chances of poor neurologic outcome with increasing age. The model indicates that there may be an increasing protective benefit from the filter with increasing age, although the interaction was not significant. CONCLUSIONS: The extraction of particulate emboli using intra-aortic filtration resulted in decreased neurologic outcomes. 相似文献
106.
A 61-year-old man with Hodgkin lymphoma (mixed type), with lymph node manifestations and extranodal and bone marrow involvement in both supra- and infradiaphragmatic locations (stage 4), had dyspnea and tachycardia on echocardiography. There were pleural and pericardial effusions and thickening of the epicardium and pericardium. These findings and computed tomographic findings were suspicious for manifestations of Hodgkin lymphoma. The pericardial findings were demonstrated on F-18 fluorodeoxyglucose positron emission tomographic imaging. 相似文献
107.
Insulin affects vascular smooth muscle cell phenotype and migration via distinct signaling pathways 总被引:13,自引:0,他引:13
Insulin maintains vascular smooth muscle cell (VSMC) quiescence yet can also promote VSMC migration. The mechanisms by which insulin exerts these contrasting effects were examined using alpha-smooth muscle actin (alpha-SMA) as a marker of VSMC phenotype because alpha-SMA is highly expressed in quiescent but not migratory VSMC. Insulin alone maintained VSMC quiescence and modestly stimulated VSMC migration. Wortmannin, a phosphatidylinositol 3-kinase (PI3K) inhibitor, decreased insulin-stimulated expression of alpha-SMA mRNA by 26% and protein by 48% but had no effect on VSMC migration. PD98059, a mitogen-activated protein kinase (MAPK) kinase inhibitor, decreased insulin-induced VSMC migration by 52% but did not affect alpha-SMA levels. Platelet-derived growth factor (PDGF) promoted dedifferentiation of VSMC, and insulin counteracted this effect. Furthermore, insulin increased alpha-SMA mRNA and protein levels to 111 and 118%, respectively, after PDGF-induced dedifferentiation, an effect inhibited by wortmannin. In conclusion, insulin's ability to maintain VSMC quiescence and reverse the dedifferentiating influence of PDGF is mediated via the PI3K pathway, whereas insulin promotes VSMC migration via the MAPK pathway. Thus, with impaired PI 3-kinase signaling and intact MAPK signaling, as seen in insulin resistance, insulin may lose its ability to maintain VSMC quiescence and instead promote VSMC migration. 相似文献
108.
Grills IS Kestin LL Goldstein N Mitchell C Martinez A Ingold J Vicini FA 《International journal of radiation oncology, biology, physics》2003,56(3):658-670
PURPOSE: To determine the incidence of, and risk factors for, regional nodal failure (RNF) and to evaluate the effectiveness of, and indications for, regional nodal irradiation (RNI) in patients with Stage I-II breast cancer treated with breast-conserving therapy. METHOD AND MATERIALS: A total of 1500 cases of Stage I-II breast cancer were treated with breast-conserving therapy between February 1980 and December 2000. All patients underwent excisional biopsy, and 925 (62%) underwent re-excision. Level I-II axillary lymph node dissection was done in 94% of patients. The lymph nodes were pathologically involved in 335 patients (22%); 255 with 1-3 nodes and 80 with >/=4 nodes involved. All patients received whole breast irradiation to a median dose of 45 Gy, and 97% received a tumor bed boost to a median dose of 61 Gy. Treatment included the breast only in 1309 patients (87%), and the breast and regional lymphatics in 191 (13%). RESULTS: With a median follow-up of 8.1 years, 35 patients had failure within the regional nodes: 12 patients (6%) who received RNI and 23 patients (2%) who did not. The 5- and 10-year rate for any RNF was 1.9% and 2.8%, respectively. The 5 and 10-year rates of axillary failure and supraclavicular failure were 0.6% and 1.0% and 0.9% and 1.6%, respectively. In patients with >/=4 positive lymph nodes, RNI reduced the 10-year rate of any RNF from 11% to 2% (p = 0.024), the rate of axillary failure from 5% to 0% (p = 0.019), and the rate of supraclavicular failure from 11% to 2% (p = 0.114). RNI did not affect the rate of axillary failure or supraclavicular failure in patients with 1-3 positive nodes. In node-negative patients, the rate of RNF was significantly greater if <6 nodes were removed at the time of axillary dissection. Multiple clinical, pathologic, and treatment-related factors were analyzed for association with RNF. On univariate analysis, RNF was associated with the number of nodes excised, number of positive nodes, percentage of positive nodes, size of nodal metastasis, presence of angiolymphatic invasion, estrogen receptor status, age, systemic chemotherapy, and RNI. Three subsets of patients had unusually high rates of RNF, those with >/=67% nodes positive (16%), nodal metastasis >/=2.0 cm (44%), or age =35 years (14%). On multivariate analysis, the only significant predictor of RNF was the maximal size of the nodal metastasis. RNI did not improve the overall survival for any subset of patients. The number of lymph nodes excised had an impact on overall survival, with a 10-year survival rate of 33%, 65%, and 69% in patients with <6, 6-10, and >10 nodes excised, respectively (p = 0.05). CONCLUSION: Failure within the regional lymph nodes as an isolated site of first relapse is uncommon in patients with Stage I-II breast cancer treated with breast-conserving therapy. RNI can significantly reduce the rate of RNF (axillary failure) in patients with >/=4 positive lymph nodes. The maximal size of the lymph node metastasis was found to be the only significant independent predictor of RNF, with nodal metastases >/=2.0 cm associated with extremely high regional failure rates. Despite this, young age and the extent of axillary dissection (particularly as related to the number of positive nodes) also appear to be important and should be considered when evaluating patients for RNI. Inadequate axillary dissection was not only associated with increased regional failure, but also reduced survival. 相似文献
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110.