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71.
Promyelocytic leukemic HL-60 cells were incubated with different fatty acids. Arachidonic acid (AA; 20:4, n-6) and eicosapentaenoic acid (EPA; 20:5, n-3) were the most potent inhibitors of proliferation in a dose- dependent way. Retinoic acid (RA) was used as a positive control. Inhibitors of cyclooxygenase and lipoxygenase or addition of antioxidants did not influence the effect of EPA or AA on cell proliferation. Increased capacity to generate superoxide anions after phorbol ester treatment and a reduced serglycin messenger RNA level in cells treated with AA or EPA indicated that these fatty acids induced differentiation in HL-60 cells similar to that induced by RA. However, down-regulation of the c-myc mRNA level, also typical for differentiation with RA in HL-60 cells, was not observed in cells incubated with AA or EPA. Flow cytometric analyses showed that in cultures incubated with AA or EPA, the proportion of cells in the G1 phase of the cell cycle increased. Similar effects were observed with RA. By flow cytometry and light scatter analyses it could be shown that AA made 8% of the cells apoptotic and 7% necrotic. The corresponding numbers were 21% and 10% for RA-treated cells, and 19% and 32% for EPA- treated cells. The present study shows that AA and EPA reduce the proliferation rate of HL-60 cells. This is mediated by mechanisms independent of eicosanoids or lipid peroxidation products and is due to effects both on apoptosis/necrosis and cell differentiation.  相似文献   
72.
Gjerset  GF; Martin  PJ; Counts  RB; Fast  LD; Hansen  JA 《Blood》1984,64(3):715-720
We evaluated 37 patients with moderate or severe hemophilia A and six patients with severe factor IX deficiency for clinical or laboratory evidence of immune abnormalities. Patients were assigned to one of four groups according to the type of clotting factor replacement. Twenty patients had received only cryoprecipitate during the two years preceding the evaluation (group I); 11 additional patients were treated predominantly with cryoprecipitate but had also received up to nine bottles of factor VIII concentrate (group II); six patients received factor VIII concentrate (group III); six patients received factor IX concentrate (group IV). There was no clinical or laboratory evidence of immunodeficiency among the 43 patients. The mean absolute number of Th cells was normal in all patient groups, but the mean absolute number of Ts cells was increased compared with controls, both in patients treated with cryoprecipitate and in patients treated with factor VIII or factor IX concentrate. There was no correlation between the Th/Ts ratio and patient age, alanine aminotransferase level, hepatitis serology, in vitro lymphocyte function, or amount of clotting factor administered. Our observations demonstrate that the volunteer or commercial origin of clotting factor replacement cannot fully explain the alterations in lymphocyte subset distribution previously described in patients with hemophilia A.  相似文献   
73.
Corzo  D; Yunis  JJ; Salazar  M; Lieberman  JA; Howard  A; Awdeh  Z; Alper  CA; Yunis  EJ 《Blood》1995,86(10):3835-3840
Genes of the major histocompatibility complex (MHC) have been associated with susceptibility to drug-induced adverse reactions. We previously found that clozapine-induced agranulocytosis (CA) is associated with the HLA-DRB1*0402, DRB4*0101, DQB1*0302, DQA1*0301 haplotype in Ashkenazi Jewish patients and with the HLA-DRB1*1601, DRB5*02, DQB1*0502, DQA1*0102 haplotype in non-Jewish patients. In the present study, we tested the hypothesis that the variants of the heat- shock protein 70 (HSP-70) encoded by the HSP-70 loci located within the MHC region and known to be involved in apoptosis and regulation of cell proliferation could play an important role in molecular mechanisms of CA. First, we analyzed HSP70-2 polymorphism in risk-associated haplotypes from HLA homozygous cells and normal individuals and confirmed that the HSP70-2 9-kb variant was associated invariably with DR4 (HLA-DRB1*0402, DQB1*0302) and DR2 (HLA-DRB1*01601, DQB1*0502, DQA1*0102 and HLA-DRB1*1501, DQB1*0602) haplotypes, which were the haplotypes found increased in Jewish and non-Jewish patients with CA, respectively. The 9.0-kb variant was also found to be associated with HLA-B44, DRB1*0401 and HLA-B44, DRB1*07 haplotypes. Second, in patients with CA (12 Ashkenazi Jewish and 20 non-Jewish patients), HSP70-1 A and HSP70-2 9.0-kb variants were associated with the MHC haplotypes found by us to be markers of susceptibility to CA. The clozapine-treated control group had an excess number of HSP70-1 C and HSP70-2 8.5-kb variants, consistent with genetic resistance to CA associated with those variants. This finding supports our hypothesis that a dominant gene within the MHC region (marked by HSP70-1 and HSP70-2), but not necessarily HLA, is associated with CA in two different ethnic groups.  相似文献   
74.
Since the early days of antiretroviral therapy, adherence has emerged as the milestone of success; in fact, it is the most potent predictor of effectiveness. The main factors related to adherence include the complexity of the therapeutic regimen, adverse effects, psychological problems, alcoholism and active addiction to drugs, lack of social and family support and the patient's beliefs and attitudes about the treatment. Adherence monitoring should be part of the HIV patient's regular care, and should be done with feasible, easily applied methods adapted to the different clinical settings. The minimally acceptable measures should include use of a validated questionnaire, together with data from the Pharmacy Department's drug dispensation registry. All patients that begin HAART or undergo a change of treatment should participate in a treatment education program imparted by health professionals with knowledge and experience in the management of patients with HIV infection. The health team (doctors, pharmacists and nursing professionals) should offer maximum availability to solve the doubts and problems that may occur during treatment. When sub-optimal adherence is detected, intervention strategies based on psychological therapy, educational efforts and personal advice should be attempted, in order to adapt the treatment scheme to the patient's habits and provide solutions to the problem of non-compliance. In certain situations, co-morbid conditions will also require attention. Treatment adherence, being a multidimensional problem, needs a multidisciplinary team approach. The choice of therapy, only one aspect of the multidimensional problem of adherence, must be a careful and individualized decision; however, simpler regimens with regard to the number of pills and daily dose are desirable.  相似文献   
75.
Chronic thromboembolic pulmonary hypertension is a rare sequela to an acute untreated or recurrent pulmonary embolism. The mechanisms that underlie the failure to resolve the thrombus are still uncertain. As most patients are not diagnosed until a relatively late stage, little is known about the course of their illness. We report the case of a 51-year-old woman who had previously been diagnosed with and operated on for endomyocardial fibrosis of the right ventricle and who developed chronic thromboembolic pulmonary hypertension several years later.  相似文献   
76.
Summary. Twenty-four patients with multiple myeloma (MM), three (12-5%) in complete remission (CR) and 21 (87-5%) in partial remission (PR) were treated with high-dose chemotherapy (HDCT) (busulfan 12 mg/kg-l-melphalan 140mg/m2) as preparative regimen for autologous peripheral blood stem cell (PBSC) transplantation. These cells were previously collected by leukapheresis after mobilization by high-dose cyclophosphamide (HD Cy) + rhGM-CSF (18 patients) or rhG-CSF alone (six patients). Considering 23 evaluable patients following HDCT, the CR rate was 58% (14 patients) and the PR rate was 38% (nine patients). One transplant-related death occurred following this regimen (4%). With a median follow-up of 20 months (range 4-34) after transplantation, 21 patients are alive (87%). Disease progression after transplantation was observed in four patients. Overall and relapse-free actuarial survival at 24 months was 91% and 74%, respectively. 12 patients (50%) remain in CR 15 months (4-34) post transplant. The major toxicity was mucositis. Busulfan + melphalan is a safe and feasible conditioning regimen for APBSCT in MM with acceptable toxicity and a high objective response rate, which may result in prolonged survival.  相似文献   
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For decades, oral implants have been used successfully for the replacement of missing teeth. Nevertheless, peri‐implant diseases have become an increasingly important issue in daily practice. In this working group, the prevalence of peri‐implant mucositis and peri‐implantitis, as well as different general risk factors and their impact on the onset and progression of peri‐implant diseases, were discussed based on reviews reflecting the current state of evidence. The influence of smoking on the peri‐implant bone‐healing process and its association with peri‐implantitis has been explored in the current literature, demonstrating that smoking is an important risk indicator for the development of peri‐implantitis and implant loss. Compared with non‐smokers, smokers have a higher potential for pathological peri‐implant bone loss, which is also influenced by poor oral hygiene. Despite the fact that a growing number of genetic polymorphisms have been identified and related to periodontal diseases, there are still no genetic patterns that could act as adjuncts to clinical diagnostics in order to identify patients at higher risk of peri‐implant diseases. Long‐term medications, such as bisphosphonate therapy (> 3 years), may have an impact on implant loss. A higher incidence of implant failure was reported in patients using selective serotonin reuptake inhibitors in anti‐depression therapy. Alcoholism (defined as more than 5 units a day) has been associated with implant loss in retrospective and case–control studies, as well as in animal studies.  相似文献   
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