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Immunotherapy has raised the attention of many scientists because it hold promise to be an attractive therapeutic strategy to treat a number of disorders. In this study, the immunomodulatory effects of low titers of Newcastle disease virus (NDV) AF2240 on human peripheral blood mononuclear cells (PBMC) were analyzed. We evaluated cytokine secretion and PBMC activation by cell proliferation assay, immunophenotyping and enzyme linked immunosorbent assay. The proliferation of the human PBMC was measured to be 28.5% and 36.5% upon treatment with 8 hemaglutinin unit (HAU) and 2 HAU of NDV respectively. Interestingly, the percentage of cells with activating markers CD16 and CD56 were increased significantly. Furthermore, the intracellular perforin and granzyme levels were also increased upon virus infection. Human PBMC treated with NDV titer 8 HAU was found to stimulate the highest level of cytokine production including interferon-γ, interleukin-2 and interleukin-12. The release of these proteins contributes to the antitumor effect of PBMC against MCF-7 breast cancer cells. Based on the 3-(4, 5-dimethylthiazol-2-yl)-2, 5-diphenyl tetrazolium bromide assay, activated human PBMC showed high cytolytic efficiency towards human breast tumor cells. In summary, NDV was able to stimulate PBMC proliferation, cytokine secretion and cytolytic activity.  相似文献   
54.

Background

Understanding the relationship between alcohol abuse, a common and theoretically modifiable condition, and the most common cause of death in the world, cardiovascular disease, may inform potential prevention strategies.

Objectives

The study sought to investigate the associations among alcohol abuse and atrial fibrillation (AF), myocardial infarction (MI), and congestive heart failure (CHF).

Methods

Using the Healthcare Cost and Utilization Project database, we performed a longitudinal analysis of California residents ≥21 years of age who received ambulatory surgery, emergency, or inpatient medical care in California between 2005 and 2009. We determined the risk of an alcohol abuse diagnosis on incident AF, MI, and CHF. Patient characteristics modifying the associations and population-attributable risks were determined.

Results

Among 14,727,591 patients, 268,084 (1.8%) had alcohol abuse. After multivariable adjustment, alcohol abuse was associated with an increased risk of incident AF (hazard ratio [HR]: 2.14; 95% confidence interval [CI]: 2.08 to 2.19; p < 0.0001), MI (HR: 1.45; 95% CI: 1.40 to 1.51; p < 0.0001), and CHF (HR: 2.34; 95% CI: 2.29 to 2.39; p < 0.0001). In interaction analyses, individuals without conventional risk factors for cardiovascular disease exhibited a disproportionately enhanced risk of each outcome. The population-attributable risk of alcohol abuse on each outcome was of similar magnitude to other well-recognized modifiable risk factors.

Conclusions

Alcohol abuse increased the risk of AF, MI, and CHF to a similar degree as other well-established risk factors. Those without traditional cardiovascular risk factors are disproportionately prone to these cardiac diseases in the setting of alcohol abuse. Thus, efforts to mitigate alcohol abuse might result in meaningful reductions of cardiovascular disease.  相似文献   
55.

Background

The underlying mechanisms sustaining human persistent atrial fibrillation (PsAF) is poorly understood.

Objectives

This study sought to investigate the complexity and distribution of AF drivers in PsAF of varying durations.

Methods

Of 135 consecutive patients with PsAF, 105 patients referred for de novo ablation of PsAF were prospectively recruited. Patients were divided into 3 groups according to AF duration: PsAF presenting in sinus rhythm (AF induced), PsAF <12 months, and PsAF >12 months. Patients wore a 252-electrode vest for body surface mapping. Localized drivers (re-entrant or focal) were identified using phase-mapping algorithms.

Results

In this patient cohort, the most prominent re-entrant driver regions included the pulmonary vein (PV) regions and inferoposterior left atrial wall. Focal drivers were observed in 1 or both PV regions in 75% of patients. Comparing between the 3 groups, with longer AF duration AF complexity increased, reflected by increased number of re-entrant rotations (p < 0.05), number of re-entrant rotations and focal events (p < 0.05), and number of regions harboring re-entrant (p < 0.01) and focal (p < 0.05) drivers. With increased AF duration, a higher proportion of patients had multiple extra-PV driver regions, specifically in the inferoposterior left atrium (p < 0.01), superior right atrium (p < 0.05), and inferior right atrium (p < 0.05). Procedural AF termination was achieved in 70% of patients, but decreased with longer AF duration.

Conclusions

The complexity of AF drivers increases with prolonged AF duration. Re-entrant and focal drivers are predominantly located in the PV antral and adjacent regions. However, with longer AF duration, multiple drivers are distributed at extra-PV sites. AF termination rate declines as patients progress to longstanding PsAF, underscoring the importance of early intervention.  相似文献   
56.
ObjectivesThe purpose of the study was to investigate the impact of oral anticoagulation (OAC) type on clinical outcomes 1 year after transcatheter aortic valve replacement (TAVR).BackgroundNon–vitamin K oral anticoagulants (NOACs) are superior to vitamin K antagonists (VKAs) in nonvalvular atrial fibrillation (AF), while their comparative performance among patients in need of OAC undergoing TAVR is underinvestigated.MethodsThe study enrolled 962 consecutive patients who underwent TAVR in 4 tertiary European centers and were discharged on either NOACs (n = 326) or VKAs (n = 636). By using propensity scores for inverse probability of treatment weighting (IPTW), the comparison of treatment groups was adjusted to correct for potential confounding.ResultsMean age and Society of Thoracic Surgeons score of the population were 81.3 ± 6.3 years and 4.5% (interquartile range: 3.0% to 7.3%); 52.5% were women and a balloon-expandable valve was used in 62.7% of cases. The primary outcome of interest, combined incidence of all-cause mortality, myocardial infarction, and any cerebrovascular event at 1-year after TAVR, was 21.2% with NOACs versus 15.0% with VKAs (hazard ratio [HR]: 1.44; 95% confidence interval [CI]: 1.00 to 2.07; p = 0.050, IPTW-adjusted). The 1-year incidence of any Bleeding Academic Research Consortium bleeds and all-cause mortality were comparable between the NOAC and VKA groups, 33.9% versus 34.1% (HR: 0.97; 95% CI: 0.74 to 1.26; p = 0.838, IPTW-adjusted) and 16.5% versus 12.2% (HR: 1.36; 95% CI: 0.90 to 2.06; p = 0.136, IPTW-adjusted), respectively.ConclusionsChronic use of both NOACs and VKAs among patients in need of OAC after TAVR are comparable regarding 1-year bleeding risk. The higher ischemic event rate observed with NOACs needs to be evaluated in large randomized trials.  相似文献   
57.
目的探讨环孢素A抗曼氏血吸虫童虫的作用机制。方法制备童虫,环孢素A体外作用,AF18标记,荧光显微镜观察;定量童虫荧光素的分布以及测定光漂洗后童虫荧光素的复原率。结果童虫损伤或死亡,虫体逐渐从绿色变成黄色,虫体表面损伤;随着环孢素A剂量加大,童虫荧光素定量增加;童虫光漂洗后荧光素的复原率大幅度降低。结论环孢素A增加童虫AF18的含量,降低童虫荧光素的复原率,减低童虫表膜流动性;提示,表膜是药物作用的靶标。  相似文献   
58.
预激综合征易并发室上速,但绝大多数患者无器质性心脏病,传统上认为是良性心律失常。最近发现,其死亡率占所有心性猝死的0.15%-0.39%,且猝死者也多数无器质性心脏病,主要死于合并心肌梗死或心律失常,故提高对其合并症诊断及危险分层的能力,及时进行干预,具有重要的临床意义。为此,将其有关问题进行综述。  相似文献   
59.
Objective: The aim of this study was to observe the affection of targeted therapy to plasmid AF-pGL3-hTERT-TK in HCC cell line HepG2. Methods: We constructed therapeutic plasmid pGL3-hTERT-TK (containing suicide gene TK that promoted by promoter of hTERT) and was conjugated with AF-liposome (a protein that can combine with the receptor ASPGR on HCC cell surface). Then we transfected HCC cell line HepG2 and hepatic cell L02 with AF-pGL3-hTERT-TK, observed the effects of therapeutic plasmid AF-pGL3-hTERT-TK for HCC cell line growth and apoptosis in vitro by Flow cytometry and Tun- nel method. Results: Our results showed that TK gene was 1100 bp in plasmid pGL3-hTERT-TK. Plasmid pGL3-hTERT-TK can effectively transfect HCC cell HepG2 and the transfection rate was 8.91%. By recognizing and combining effects of recep- tor protein ASPGR on HCC cell surface the therapeutic plasmid AF-pGL3-hTERT-TK could easily enter into HCC cell HepG2 and induce its apeptosis. The apoptosis rate was 85.87% while only 8.65% in L02 cell. Four days after AF-pGL3-hTERT-TK transfected HepG2 was intervention by ganciclovir (GCV), a lot of apeptotic bodies were found by Tunnel analysis, while little apoptotic body was found in hepatic cell L02. Conclusion: AF-pGL3-hTERT-TK can target to HCC cell line and induce it to apoptesis, almost has no influence on hepatic cell L02. AF-pGL3-hTERT-TK has the potential therapeutic effects for HCC.  相似文献   
60.
胸腰段骨折是脊柱常见的损伤 ,上个世纪 80年代起我们采用哈氏或卢氏棒操作内固定 ,收到了一定效果。近几年随着内固定器材的发展 ,我们采用AF系统治疗胸腰段骨折2 2例 ,效果满意 ,报告如下。1 临床资料1.1 一般资料 :本组共 2 2例 ,男 17例 ,女 5例 ;年龄 2 1~ 4 5岁 ,平均 38岁。伤后 1周内手术 15例 ,2周内 5例 ,4周内 2例。损伤部位 :T10 1例 ,T114例 ,T12 8例 ,L16例 ,L2 3例。不全截瘫 16例 ,全瘫 6例。  X线检查显示椎体压缩性骨折 11例 ,爆裂性骨折 8例 ,Chance骨折 3例。所有骨折患者CT扫描显示伤椎均有骨椎管狭窄或骨块…  相似文献   
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