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71.
《Vaccine》2022,40(48):6971-6978
Background and aimsRecent studies have reported poor humoral immune response to mRNA vaccines in patients with chronic liver disease (CLD). However, the immunogenicity of ChAdOx1 (vector-based) and BBV152 (inactivated virus) vaccines in patients with CLD and liver transplant recipients (LTRs) is unknown. Therefore, we aimed to assess the immunogenicity of ChAdOx1 and BBV152 vaccines in patients with CLD (including cirrhosis patients) and LTRs.MethodsIn this single-center prospective study, consecutive completely vaccinated (ChAdOx1 or BBV152) non-cirrhosis CLD patients, those with cirrhosis, and LTRs were compared with matched healthy controls for anti-spike antibody and cellular response.ResultsSixty healthy individuals, 50 NCCLD patients, 63 compensated and 50 decompensated cirrhosis, and 17 LTRs were included. The proportion of non-responders was similar among the healthy control (8 %), non-cirrhosis CLD (16 %), and compensated cirrhosis groups (17.5 %;p = 0.3). However, a higher proportion of patients with decompensated cirrhosis (34 %) and LTRs (59 %) were non-responders than the healthy controls (p = 0.001). Cluster of differentiation (CD) 4-effector cells were lower in patients with non-cirrhosis CLD and compensated cirrhosis. CD4-naïve, CD4-effector, B, and B-memory cells were lower in the decompensated cirrhosis group. Although the central memory cells were higher in the decompensated cirrhosis group, they could not differentiate into effector cells. CD4- and CD8-naïve cells were higher in the marrow in the LTRs, while the CD4-effector memory cells and CD4- and CD8-effector cells were lower in the LTRs. Furthermore, B cells were more deficient in the LTRs, suggesting poor antibody response.ConclusionPatients with decompensated cirrhosis and LTRs demonstrated suboptimal humoral and cellular immune responses against recombinant and inactivated COVID-19 vaccines.  相似文献   
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Study Objective

To evaluate the risk of posttransplantation malignancy in renal transplant recipients exposed to pretransplantation cyclophosphamide for the treatment of glomerular nephropathy (GN).

Design

Retrospective cohort study.

Setting

Tertiary academic medical center.

Patients

Six hundred adult renal transplant recipients were transplanted between 1993 and 2014; 54 patients were exposed to pretransplantation cyclophosphamide for treatment of GN (GN‐CYC group), and 546 patients with polycystic kidney disease were not exposed to pretransplantation cyclophosphamide (PKD group).

Measurement and Main Results

Data were collected retrospectively from electronic medical records. The primary outcome was occurrence of posttransplantation malignancy. During a median follow‐up of 5.5 years, 130 patients developed malignancy (incidence rate 3.5 events per 100 person‐yrs). Exposure to cyclophosphamide before transplantation was significantly associated with malignancy after transplantation (adjusted hazard ratio [aHR] 2.20, 95% confidence interval [CI] 1.16–4.22, p=0.02), specifically skin cancer (aHR 2.24, 95% CI 1.09–4.60, p=0.03). Malignancy risk in the GN‐CYC group was higher in the setting of lymphocyte‐depleting induction (alemtuzumab; aHR 4.53, 95% CI 0.99–20.72, p=0.05) compared with basiliximab induction. Incidences of death‐censored graft loss and mortality were similar between the GN‐CYC and PKD groups.

Conclusion

In our observational study, renal transplant recipients exposed to pretransplantation cyclophosphamide appeared to have a higher risk of developing a malignancy compared with unexposed renal transplant recipients. Further investigation into the impact of pretransplantation immunosuppression on malignancy, particularly the compounded effect with lymphocyte‐depleting induction, is warranted.  相似文献   
75.
冯丽娟  杨春兰  夏泉  廖贵益  许杜娟 《安徽医药》2018,39(12):1446-1450
目的 探讨免疫抑制剂霉酚酸酯(MMF)、他克莫司(FK506)血药浓度与肾移植术后腹泻之间的关系。方法 选取2015年8月至2017年8月在安徽医科大学第一附属医院行肾移植手术的146例受者,根据术后是否发生腹泻分为两组,未发生腹泻的患者为非腹泻组(83例)、发生腹泻且大于1次者为腹泻组(63例),测定受者的霉酚酸谷浓度(MPA-C0)和FK506谷浓度(FK506-C0),记录术后出现的腹泻情况,运用统计软件分析MPA-C0和FK506-C0与腹泻间的关系。结果 腹泻组与非腹泻组之间MPA-C0差异无统计学意义(P>0.05),FK506-C0差异有统计学意(P<0.001);ROC曲线分析显示,FK506-C0仅在术后1个月差异有统计学意义(曲线下面积0.607,P<0.05),FK506 C0<11.15 ng/mL是术后1个月发生腹泻的截断值,敏感度51.90%,特异性63.60%;MPA-C0与FK506-C0对腹泻发生不存在交互作用(P>0.05)。结论 MPA-C0与腹泻的发生没有关联性,而较高的FK506-C0易导致肾移植术后腹泻,其中术后1个月FK506-C0 <11.15 ng/mL是发生腹泻的的最佳截断值。  相似文献   
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High-risk neuroblastoma has a poor prognosis, and research studies have shown that increasing the intensity of therapy improves outcomes. Autologous hematopoietic cell transplant (aHCT) as consolidation therapy confers a significant survival advantage but is accompanied by significant morbidity. Transplant-associated thrombotic microangiopathy (TA-TMA) is a life-threatening complication caused by endothelial injury that often leads to hemolytic anemia, microthrombotic platelet consumption, and renal injury. Here we investigated the incidence, potential risk factors, and sequelae of TA-TMA in patients with high-risk neuroblastoma. We conducted a retrospective chart review of all patients (n = 141) with neuroblastoma in our institutions who underwent aHCT from 2000 to 2017. Ten patients (7%) developed TA-TMA. The patients in the TA-TMA group were similar to the rest of the subjects in demographics, disease burden, prior therapies, renal function, and timing of transplant. The type of conditioning regimen was the only statistically significant pretransplant variable (P < .001). Six of 15 patients (40%) intended to receive tandem transplants (cyclophosphamide/thiotepa and then carboplatin/etoposide/melphalan (CEM)), 4 of 68 patients (6%) who received conditioning with single CEM, and none of the 56 patients who received busulfan/melphalan were diagnosed with TA-TMA. Patients with TA-TMA were more likely to require intensive care unit transfer, have a longer length of stay in the hospital, and experience a delay or change in their subsequent therapy. In our cohort overall, patients with a delay in therapy after transplant appeared to have a worse overall survival, although the difference was not statistically significant. Because of this high incidence and significant morbidity, we have implemented standardized screening for TA-TMA during and after transplant. We anticipate that screening will lead to earlier intervention and decreased severity of disease.  相似文献   
79.
Peripheral blood (PB) and bone marrow (BM) from unrelated donors can serve as a graft source for hematopoietic cell transplantation (HCT). Currently, PB is most commonly used in roughly 80% of adult recipients. Determining the long-term impact of graft source on outcomes would inform this decision. Data collected by the Center for International Blood and Marrow Transplant Research from 5200 adult recipients of a first HCT from an 8/8 or 7/8 HLA antigen-matched unrelated donor for treatment of acute leukemia, chronic myelogenous leukemia, or myelodysplastic syndrome between 2001 and 2011 were analyzed to determine the impact of graft source on graft-versus-host disease (GVHD) relapse-free survival (GRFS), defined as freedom from grade III/IV acute GVHD, chronic GVHD requiring immunosuppressive therapy, relapse, and death, and overall survival. GRFS at 2 years was superior in BM recipients compared with PB recipients (16%; 95% confidence interval [CI], 14% to 18% versus 10%; 95% CI, 8% to 11%; P <.0001) in the 8/8 HLA-matched cohort and 7/8 HLA-matched cohort (11%; 95% CI, 8% to 14% versus 5%; 95% CI, 4% to 7%; P?=?.001). With 8/8 HLA-matched unrelated donors, overall survival at 5 years was superior in recipients of BM (43%; 95% CI, 40% to 46% versus 38%; 95% CI, 36% to 40%; P?=?.014). The inferior 5-year survival in the PB cohort was attributable to a higher frequency of deaths while in remission compared with the BM cohort. For recipients of 7/8 HLA-matched grafts, survival at 5 years was similar in BM recipients and PB recipients (32% versus 29%; P?=?.329). BM grafts are associated with improved long-term GRFS and overall survival in recipients of matched unrelated donor HCT and should be considered the unrelated allograft of choice, when available, for adults with acute leukemia, chronic myelogenous leukemia, and myelodysplastic syndrome.  相似文献   
80.
Pharmacogenetics influences oral tacrolimus exposure; however, little data exist regarding i.v. tacrolimus. We investigated the impact of genetic polymorphisms in CYP3A4, CYP3A5, and ABCB1 on i.v. tacrolimus exposure and toxicity in adult patients receiving an allogeneic hematopoietic stem cell transplant for hematologic malignancies. Germline DNA was extracted from buccal swabs and genotyped for CYP3A4, CYP3A5, and ABCB1 polymorphisms. Continuous i.v. infusion of tacrolimus .03 mg/kg/day was initiated on day +5 post-transplant, and steady-state blood concentrations were measured 4days later. We evaluated the association between phenotypes and prevalence of nontherapeutic target concentrations (below or above 5 to 15 ng/mL) as well as tacrolimus-related toxicities. Of 63 patients, 28.6% achieved the target concentration; 71.4% were >15ng/mL, which was more common in CYP3A4 intermediate/normal metabolizers (compared with rapid) and those with at least 1 ABCB1 C2677T loss-of-function allele (P < .05). ABCB1 C2677T was significantly associated with concentrations >15ng/mL (odds ratio, 6.2; 95% confidence interval, 1.8 to 23.6; P = .004) and tacrolimus-related toxicities (odds ratio, 7.5; 95% confidence interval, 1.6 to 55.2; P = .02). ABCB1 C2677T and CYP3A4 are important determinants of i.v. tacrolimus exposure, whereas ABCB1 C2677T also impacts tacrolimus-related toxicities in stem cell transplants.  相似文献   
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