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51.
A large number of studies have been carried out to identify the Friend leukemia virus (FV) target cell(s). In FV-infected mice, the kinetics of "primitive" erythroid burst-forming units (P-BFU-E) is perturbed, and their proliferative rate is enhanced. These results indirectly suggest, but do not prove, that cycling P-BFU-E may serve as FV target. In vitro infection studies showed that normal erythroid colony forming units (CFU-E) and "mature" erythroid burst-forming units (M-BFU-E) are targets for FV, while the largely out-of-cycle normal P-BFU-E are not. In an attempt to shed light on these aspects, we have evaluated the expression of viral cytoplasmic RNA sequences in pools of colonies generated by P-BFU-E and granulocyte-macrophage colony forming units (CFU-GM) from spleen and marrow of polycythemic Friend virus (FVP)-infected mice, as measured by liquid hybridization with FVP- or spleen focus-forming polycythemic virus (SFFVp)-specific DNA probes. Moreover, similar assays were performed on RNAs derived from whole spleen or bone marrow from mice treated with FVP or the anemic strain of Friend virus (FVA). Control studies were performed on corresponding colonies and whole tissues from normal animals. FVP- and SFFVp-specific sequences are more abundant in RNA extracted from infected spleen as compared to marrow by a 10-fold factor. On the other hand, FVP and SFFVp-specific sequences are expressed at a comparable level in both P-BFU-E- and CFU-GM-derived colonies from spleen or marrow of FVP-treated mice. Since in vitro spread of FVP infection was excluded by control studies with addition in culture of antibody to the viral glycoprotein with a molecular weight of 70,000 (gp70) these results indicate that P-BFU-E and CFU-GM are infected in vivo by FVP.  相似文献   
52.
Seven paired HIV-1 isolates from peripheral blood mononuclear cells (PMCs) and cerebrospinal fluid (CSF) of infected subjects at various stages of the disease were studied for their capacity to replicate in continuous cell lines (Molt-3 and U-937 cells) and to induce cytopathic effects "in vitro". Obtained results indicate that paired HIV-1 isolates from PMCs and CSF of the same patient can differ in their replicative activity "in vitro", suggesting that, at least in some cases, CSF isolates may represent a distinct subtype of HIV-1.  相似文献   
53.
Three cases of an infrequent cerebral vascular malformation, venous angioma, are reported. The first 2 of these cases, with the lesion in a supratentorial location, exhibited exophthalmos as a presenting symptom, together with palpebral or intraobital angiomatous formations, and also impairment of visual function. The first patient was operated upon and the "venous angioma" could be confirmed histologically. An angiographic follow-up of the same patient at an 18 year interval was also possible. The diagnostic work-up to be performed in cases of exophthalmos is discussed and the need for angiography is stressed.  相似文献   
54.
The aim of this study was to investigate the in vitro immunomodulatory effects of zoledronic acid (Zol) on peripheral blood Vgamma9/Vdelta2 (gammadelta) T cells of normal donors and multiple myeloma (MM) patients. gammadelta T cells were stimulated with Zol and low doses of interleukin-2 (IL-2), and then analyzed for proliferation, cytokine production, and generation of effector activity against myeloma cell lines and primary myeloma cells. Proliferation of gammadelta T cells was observed in 100% of normal donors and 50% of MM patients. gammadelta T cells produced IFN-gamma, surface mobilized the CD107a and CD107b antigens, and exerted direct cell-to-cell antimyeloma activity irrespective of the ability to proliferate to Zol and IL-2. The memory phenotype was predominant in the MM gammadelta T cells that proliferated in response to Zol (responders), whereas effector cells were predominant in those that did not (nonresponders). Zol induced antimyeloma activity through the monocyte-dependent activation of gammadelta T cells and by enhancing the immunosensitivity of myeloma cells to gammadelta T cells. Mevastatin, a specific inhibitor of hydroxy-methylglutaryl-CoA reductase, completely abrogated this antimyeloma activity.  相似文献   
55.
PURPOSE: To explore the safety and therapeutic activity of combination anti-B-cell monoclonal antibody therapy in non-Hodgkin's lymphoma (NHL). PATIENTS AND METHODS: Twenty-three patients with recurrent B-cell lymphoma received anti-CD22 epratuzumab 360 mg/m(2) and anti-CD20 rituximab 375 mg/m(2) monoclonal antibodies weekly for four doses each. Sixteen patients had indolent histologies (15 with follicular lymphoma) and seven had aggressive NHL (all diffuse large B-cell lymphoma [DLBCL]). Indolent patients had received a median of one (range, one to six) prior treatment, with 31% refractory to their last therapy and 81% with high-risk Follicular Lymphoma International Prognostic Index scores. Patients with DLBCL had a median of three (range, one to eight) prior regimens (14% resistant to last treatment) and 71% had high intermediate-risk or high-risk International Prognostic Index scores. All patients were rituximab na?ve. RESULTS: Treatment was well tolerated, with toxicities principally infusion-related and predominantly grade 1 or 2. Ten (67%) patients with follicular NHL achieved an objective response (OR), including nine of 15 (60%) with complete responses (CRs and unconfirmed CRs). Four of six assessable patients (67%) with DLBCL achieved an OR, including three (50%) CRs. Median time to progression for all indolent NHL patients was 17.8 months. CONCLUSION: The full-dose combination of epratuzumab with rituximab was well tolerated and had significant clinical activity in NHL, suggesting that this combination should be tested in comparison with single-agent treatment.  相似文献   
56.
PURPOSE: To evaluate the safety and efficacy of a sequential chemotherapy plus radioimmunotherapy (RIT) regimen in previously untreated follicular non-Hodgkin's lymphoma. PATIENTS AND METHODS: Thirty-five patients received an abbreviated course (three cycles) of fludarabine followed 6 to 8 weeks later by tositumomab and iodine I 131 tositumomab. RESULTS: After fludarabine, 31 (89%) of 35 patients responded, with three (9%) of 31 patients achieving a complete response (CR). After the full regimen of fludarabine and iodine I 131 tositumomab, all 35 patients responded; 30 (86%) of 35 patients achieved CR, and five (14%) of 35 achieved partial response. After a median follow-up of 58 months, the median progression-free survival (PFS) had not been reached (95% CI, 27 months to not reached), but it will be at least 48 months. The 5-year estimated PFS rate is 60%. Baseline Follicular Lymphoma International Prognostic Index (FLIPI) was significantly associated (P = .003) with PFS. Five of six patients with more than 25% bone marrow involvement at baseline achieved adequate bone marrow cytoreduction to receive standard-dose iodine I 131 tositumomab. Ten (77%) of 13 patients with baseline bone marrow Bcl-2 positivity demonstrated molecular remissions at month 12. Toxicities were manageable and principally hematologic. Two (6%) of 35 patients developed human antimurine antibodies (HAMA) after RIT. CONCLUSION: Use of abbreviated fludarabine before iodine I 131 tositumomab can reduce bone marrow involvement, when needed, to allow the use of RIT and can suppress HAMA responses. This sequential treatment regimen is highly effective as front-line therapy for follicular lymphoma, particularly for low- or intermediate-risk FLIPI patients.  相似文献   
57.
PURPOSE: Between September 1991 and May 1997, within the International Berlin-Frankfurt-Muenster Study Group (I-BFM-SG), a randomized study was performed aimed at assessing the efficacy of prolonged use of high-dose l-asparaginase (HD-l-ASP) during continuation therapy in children with standard risk (SR) acute lymphoblastic leukemia (ALL), treated with a reduced BFM-type chemotherapy. PATIENTS AND METHODS: The Italian, Dutch, and Hungarian groups participated in this study denominated IDH-ALL-91, and 494 children were enrolled. Treatment consisted of a BFM-type modified backbone with omission of the IB part in induction and elimination of two doses of anthracyclines during reinduction in both arms at the beginning of continuation therapy. Patients were randomly assigned to receive (YES-ASP) or not (NO-ASP) 20 weekly HD-l-ASP (25,000 IU/m2). RESULTS: The event-free-survival and overall survival probabilities at 10 years for the entire group were 82.5% (1.8) and 90.3% (1.3), respectively. Of the 490 patients eligible for random assignment, 355 (72.4%) were randomly assigned (178 YES-ASP and 177 NO-ASP). After a median follow-up of 9 years, the probability of disease-free survival at 10 years was 87.5% (SE, 2.5) for YES-ASP arm versus 78.7% (SE, 3.3) for NO-ASP arm (P = .03). In multivariate analysis, NO-ASP arm (P = .03), male sex (P = .004), and age older than 10 years (P = .0003) had a significantly adverse impact on outcome. CONCLUSION: In this subset of patients, selected with criteria not including monitoring of minimal residual disease, application of extended HD-l-ASP may improve prognosis, compensating reduced leukemia control that results from adoption of a reduced-intensity BFM-backbone for treatment of children with SR ALL.  相似文献   
58.
59.
60.
The development of new human skeletal muscle tissue is an alternative approach to the replacement of tissue after severe damage, for example in the case of traumatic injury, where surgical reconstruction is often needed following major loss of natural tissue. Treatment to date has involved the transfer of muscle tissue from other sites, resulting in a functional loss and volume deficiency of donor sites. Approaches that seek to eliminate these problems include the relatively new solution of skeletal muscle engineering. Here there are two main components to consider: (a) the cells with their regenerative potential; and (b) the polymeric structure onto which cells are seeded and where they must perform their activities. In this paper we describe well‐defined two‐ and three‐dimensional polymeric structures able to drive the myoblast process of adhesion, proliferation and differentiation. We examine a series of polymers and protein adhesions with which to functionalize the structures, and cell‐seeding methods, with a view to defining the optimal protocol for engineering skeletal muscle tissue. All polymer samples were tested for their mechanical and biological properties, to support the validity of our results in the real context of muscle tissue engineering. Copyright © 2014 John Wiley & Sons, Ltd.  相似文献   
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