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51.
52.
Diffusion-weighted MRI (DWI) is becoming important for diagnosis and investigation of acute cerebral ischaemia. It has been reported that apparent diffusion coefficient (ADC) maps could be an indicator of reperfusion. Our aim was to use echo-planar technology to investigate this phenomenon. We report 19 patients treated by local intra-arterial thrombolysis for middle cerebral artery stroke within 6 h of the onset of symptoms, in whom we performed follow-up DWI. ADC were found to be higher in the patients with angiographically proven reperfusion. Received: 3 November 2000 Accepted: 10 January 2001  相似文献   
53.
Induction of mixed allogeneic chimerism is a promising approach for achieving donor‐specific tolerance, thereby obviating the need for life‐long immunosuppression for solid organ allograft acceptance. In mice receiving a low dose (3Gy) of total body irradiation, allogeneic bone marrow transplantation combined with anti‐CD154 tolerizes peripheral CD4 and CD8 T cells, allowing achievement of mixed chimerism with specific tolerance to donor. With this approach, peripheral CD8 T‐cell tolerance requires recipient MHC class II, CD4 T cells, B cells and DCs. Recipient‐type B cells from chimeras that were tolerant to donor still promoted CD8 T‐cell tolerance, but their role could not be replaced by donor‐type B cells. Using recipients whose B cells or DCs specifically lack MHC class I and/or class II or lack CD80 and CD86, we demonstrate that dendritic cells (DCs) must express CD80/86 and either MHC class I or class II to promote CD8 tolerance. In contrast, B cells, though required, did not need to express MHC class I or class II or CD80/86 to promote CD8 tolerance. Moreover, recipient IDO and IL‐10 were not required. Thus, antigen presentation by recipient DCs and not by B cells is critical for peripheral alloreactive CD8 T cell tolerance.  相似文献   
54.
PurposeTo compare outcomes of unresectable hepatocellular-cholangiocarcinoma (HCC-CC) with hepatocellular carcinoma (HCC) after locoregional therapy (LRT).Materials and MethodsConsecutive patients with histologically confirmed HCC-CC or HCC treated with LRT between 2007 and 2017 were retrospectively reviewed. Ten patients (8 men; median age, 60 y) with 12 HCC-CCs (mean diameter, 4.2 cm ± 1.9; mean number, 3.7 ± 3.3) treated with chemoembolization (n = 6), yttrium-90 radioembolization (n = 2), RF ablation (n = 1), or chemoembolization/RF ablation (n = 1) were compared with 124 patients (92 men; median age, 59 y) with 134 HCCs (mean diameter, 4.8 cm ± 4.0; mean number, 2.6 ± 2.2) treated with chemoembolization (n = 51), yttrium-90 radioembolization (n = 17), RF ablation (n = 41), or chemoembolization/RF ablation (n = 15). Propensity score–matched analysis with conditional logistic regression adjusted for age, sex, LRT modality, tumor-specific features, and Child-Pugh class. Tumor-volume doubling time (TVDT) before LRT and objective response rates were compared by Kruskal-Wallis and Fisher exact test; progression-free survival (PFS) and transplant-free survival (TFS) were compared by Cox proportional hazards model.ResultsOn univariate analysis, HCC-CC was associated with lower median TVDT (2.4 months vs 5.2 months, P = .03), objective response (30% vs 71%, P = .01), and median PFS (2.4 months vs 7.4 months, HR 4.3, 95% CI 2.2–8.4, P < .0001). Propensity score–matched analysis demonstrated greater distant progression (60% vs 30%, P = .003) and significantly shorter median PFS (2.4 months vs 6.0 months, HR 3.3, 95% CI 1.3–8.9, P = .017) for HCC-CC. No significant difference was observed in TFS (7.5 months vs 13.8 months, HR 1.5, 95% CI 0.4–6.1).ConclusionsHCC-CC was associated with reduced PFS and greater distant progression after LRT compared with HCC, indicating a need for adjunctive treatment strategies to improve outcomes.  相似文献   
55.
Five patients with hepatic metastases of midgut carcinoid underwent somatostatin receptor scintigraphy with indium-111 pentetreotide before and during treatment with octreotide. Octreotide treatment changed the biodistribution of 111In-pentetreotide significantly. Whereas the radioactivity in liver, spleen and kidney decreased, hepatic metastases showed increased contrast. In one patient, liver metastases could only be detected during octreotide treatment. These data suggest that the diagnostic reliability of somatostatin receptor scintigraphy in carcinoid liver metastases is not necessarily compromised by octreotide therapy. Because of different biodistributions, the detection of liver metastases may even be improved during octreotide therapy. Correspondence to: U. Dörr  相似文献   
56.
Inspired by the dynamic clamp of cellular neuroscience, this paper introduces VPI—Virtual Partner Interaction—a coupled dynamical system for studying real time interaction between a human and a machine. In this proof of concept study, human subjects coordinate hand movements with a virtual partner, an avatar of a hand whose movements are driven by a computerized version of the Haken-Kelso-Bunz (HKB) equations that have been shown to govern basic forms of human coordination. As a surrogate system for human social coordination, VPI allows one to examine regions of the parameter space not typically explored during live interactions. A number of novel behaviors never previously observed are uncovered and accounted for. Having its basis in an empirically derived theory of human coordination, VPI offers a principled approach to human-machine interaction and opens up new ways to understand how humans interact with human-like machines including identification of underlying neural mechanisms.  相似文献   
57.
58.
In November 1996, 11 lots of one U.S. manufacturer's 1996-97 trivalent influenza vaccine were voluntarily recalled because of decreasing potency of the A/Nanchang/933/95 (H3N2) component. Because the elderly are at high risk of developing influenza-related complications, we assessed the postvaccination antibody titers of nursing home residents who received recalled vaccine and assessed the antibody response to revaccination. Blood samples were collected 3 weeks after vaccination from 86 residents at three nursing homes who received recalled vaccine and 86 residents at three other nursing homes who received a different manufacturer's vaccine. Medical records were reviewed. Residents of one nursing home were later revaccinated. Blood samples were collected on the day of revaccination and again in 3 weeks. Serum was tested by hemagglutination inhibition for antibody to all three components of the 1996-97 influenza vaccine. The geometric mean antibody titer (GMT) (33 vs 55; p=0.01) and the percentage of residents with an antibody titer > or = 1:40 (52 vs 67%; p=0.04) to the A/Nanchang/933/95 component were lower among residents who received recalled vaccine compared to those who received non-recalled vaccine, but had similar GMTs against the other two vaccine components. After revaccination, the GMT to A/Nanchang/933/95 increased from 24 on the day of revaccination to 39 (p=0.01) in residents from one nursing home. Therefore, vaccination with the recalled vaccine was associated with lower postvaccination antibody titers to A/Nanchang/933/95, but not against the other two vaccine components. Revaccination was moderately effective in increasing antibody titers. With annual changes in influenza vaccine strains, routine post-release stability testing of influenza vaccine should continue.  相似文献   
59.
The safety of percutaneous liver biopsy with a 1.2 mm Menghini needle in infants aged one year or less was investigated. One hundred and eighty four procedures performed from 1975 to 1985 were reviewed. There were no deaths or major complications within 48 hours associated with the procedure. In five instances specific complications occurred: a drop in haemoglobin concentration (three), transient hypotension (one), and haematoma at the biopsy site (one). The result of liver biopsy was diagnostic in 83% of cases, compatible with unspecified metabolic disease in 8%, and normal or not diagnostic in 9%. This study suggests that percutaneous liver biopsy can be performed with relative safety in small infants if coagulation is normal and there are no major contraindications, and the results yield important diagnostic information which cannot be obtained using less invasive procedures.  相似文献   
60.
Carica papaya seed extract is currently being marketed as a nutritional supplement with purported ability "to rejuvenate the body condition and to increase energy". The product claims to improve immunity against common infection and body functioning. The present study was initiated to analyze the chemical constituents of the Carica Seed Extract and determine the potential immunomodulatory properties of the different bioactive fractions. These immunomodulatory activities of crude Carica Seed Extract and its bioactive fractions were examined in vitro using lymphocyte proliferation assays and complement-mediated hemolytic assay. Three major observations were made in this study: (1) the crude Carica Seed Extract and two other bioactive fractions significantly enhanced the phytohemagglutinin responsiveness of lymphocytes; (2) none of the Carica Seed Extract (at the concentrations used in this study) was able to protect the lymphocytes from the toxic effects of chromium; and (3) some of the bioactive fractions of Carica Seed Extract were able to significantly inhibit the classical complement-mediated hemolytic pathway. These findings provide evidence for immunostimulatory and anti-inflammatory actions of Carica Seed Extract. No single compound is likely responsible for these activities. Further purification, isolation and characterization of the active components are needed.  相似文献   
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