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991.

Background

To assess the effects of 5-(3-chlorobenzyl)-4-hexyl-2,4-dihydro-3H-1,2,4-triazole-3-thione (TP427) on the protective anticonvulsant action of four classical antiepileptic drugs (carbamazepine, phenobarbital, phenytoin and valproate) in the tonic-clonic seizure model in mice, an isobolographic transformation of data was used.

Methods

Electrically-induced tonic-clonic seizures were experimentally evoked in adult male albino Swiss mice. The anticonvulsant effects of TP427, when used singly, were determined by the calculation of the threshold increasing the dose by 20% (TID20 value). The influence of TP427 on the anticonvulsant potency of four various classical antiepileptic drugs was determined with a subthreshold method. Types of interactions between drugs were determined using the isobolographic transformation of data. Additionally, total brain antiepileptic drug concentrations were measured.

Results

TP427, when administered separately, significantly increased the threshold for electroconvulsions. The experimentally determined TID20 value for TP427 was 11.71?mg/kg. Moreover, TP427 (10?mg/kg) significantly increased the anticonvulsant activity of valproate (p?<? 0.01), but not that of carbamazepine, phenobarbital or phenytoin in the mouse tonic-clonic seizure model. Isobolographic transformation of data confirmed that the interaction between TP427 and valproate was synergistic. Pharmacokinetic study revealed that TP427 increased total brain valproate concentrations, and had no impact on total brain concentrations of carbamazepine, phenobarbital or phenytoin in mice.

Conclusion

The synergistic interaction between TP427 and valproate in the mouse tonic-clonic seizure model might occur favorable for epilepsy patients in future. The combinations of TP427 with carbamazepine, phenobarbital and phenytoin were additive in the mouse tonic-clonic seizure model and also deserves clinical attention.  相似文献   
992.
目的探讨复杂人工全膝关节置换术(total knee arthroplasty,TKA)中采用股直肌斜切辅助显露的安全性及有效性。方法回顾分析 2016 年 1 月—2017 年 5 月,采用股直肌斜切辅助显露的 19 例(29 膝)复杂 TKA 患者临床资料。其中男 9 例(13 膝),女 10 例(16 膝);年龄 34~66 岁,平均 50.2 岁。强直性脊柱炎 4 例(8 膝),类风湿性关节炎 5 例(7 膝),膝关节骨关节炎 10 例(14 膝)。病程 8~15 年,平均 10.9 年。Kellgren-LawrenceⅢ级 12 膝,Ⅳ级 17 膝。患者膝关节活动度为(19.86±7.23)°,膝关节学会评分系统(KSS)临床评分(47.86±11.26)分、功能评分(15.52±11.21)分。术后随访纳入并发症、膝关节活动度、KSS 评分、伸膝迟滞发生情况及假体松动情况。结果术后切口均Ⅰ期愈合,无感染及心脑血管意外等并发症发生。患者均获随访,随访时间 25~39 个月,平均 30.3 个月。末次随访时,患者膝关节活动度为(91.03±7.30)°,KSS 临床评分为(83.62±9.99)分、功能评分为(66.38±7.89)分,均较术前明显改善,差异有统计学意义(P<0.05)。3 膝出现伸膝迟滞,分别迟滞 10°、10°、15°。X 线片复查未见假体位置不良、松动及病理性透亮线。 结论复杂 TKA 中采用股直肌斜切能有效显露膝关节术野,减少髌腱撕脱、髌骨骨折以及股四头肌肌腱损伤等并发症的发生;采用 Krackow 肌腱缝合法修复切断的股直肌有利于术后早期膝关节功能锻炼及恢复,而且不会增加并发症发生风险。  相似文献   
993.
Necrotizing enterocolitis (NEC), a devastating infant disease characterized by severe intestinal necrosis, its pathogenesis is poorly understood, but appears to be multifactorial and highly associated with immaturity of gastrointestinal tract and immature innate-immune system. Breast-milk is effective strategy to protect infants against NEC. This study is using a NEC rat model to investigate the pathological mechanism of NEC involved intestinal-damages, and the therapeutic mechanism of sialylated human milk oligosaccharides (SHMOs) on NEC rats; also using cell model to investigate the effects of SHMOs on colon-epithelial cells (Caco-2) in-vitro.Extraction and characterization of SHMOs from breast milk, establishment of a NEC rat model, histopathological analysis and mast cell accounting of the terminal ileum were taken; The levels of DPPI, TLR4, IL-6, TNF-α, MMP-2/9 and glutathione were measured using various methods. Caco-2 cells were pre-treated with SHMOs and cultured with LPS, histamine, chymase or DPPI, cell viabilities and mitochondrial membrane potential were examined; flow cytometry was used to detect cell cycle.The accumulation of mast cells was found in the ileum of NEC rats, but prohibited by SHMOs treatment; the increased levels of TLR4, DPPI, IL-6, TNF-α, MMP-2/9 in NEC ileum were suppressed by SHMOs in-vivo. SHMOs prevented Caco-2 cells from LPS, histamine, chymase induced damages by surviving cell viability, regulating G0/G1 and S phase in cell cycles, and increasing mitochondrial membrane potential. These findings provide a new insight into the pharmacological mechanism of SHMOs treatment for NEC and suggest that SHMOs needs well attention for therapeutic aims.  相似文献   
994.
巴赫  彭强  朱耀东 《肿瘤防治研究》2020,47(12):942-946
目的 观察胃癌组织中抑癌基因PDCD4启动子区甲基化状态及其对PDCD4表达水平的影响并探讨其临床意义。方法 通过免疫组织化学、Western blot法检测胃癌组织中PDCD4蛋白的表达;RT-PCR法检测PDCD4 mRNA的表达;甲基化特异性PCR(MSP)法检测PDCD4启动子区甲基化水平。分析PDCD4表达水平以及启动子甲基化水平与胃癌患者临床病理特征之间的相关性。结果 胃癌组织中PDCD4蛋白及mRNA表达水平均显著降低(P<0.05),甲基化作用显著增强(P<0.05)。PDCD4蛋白表达缺失与胃癌的分化、临床分期以及淋巴结转移密切相关(P<0.05);PDCD4高甲基化与胃癌的淋巴结转移、临床分期密切相关(P<0.05)。PDCD4甲基化水平与PDCD4蛋白以及mRNA表达水平均呈负相关(P<0.05)。结论 胃癌组织中PDCD4表达水平显著降低,并与胃癌发展相关,启动子区高甲基化可能是PDCD4表达缺失的原因。  相似文献   
995.
The nuclear receptor Nur77 is expressed in a multitude of tissues, regulating cell differentiation and homeostasis. Dysregulation of Nur77 signaling is associated with cancer, cardiovascular disease, and disorders of the CNS. The role of Nur77 in T cells has been studied for almost 30 years now. There is a clear appreciation that Nur77 is crucial for apoptosis of self-reactive T cells. However, the regulation and function of Nur77 in mature T cells remains largely unclear. In an exciting development, Nur77 has been recently demonstrated to impinge on cancer immunotherapy involving chimeric antigen receptor (CAR) T cells and tumor infiltrating lymphocytes (TILs). These studies indicated that Nur77 deficiency reduced T cell tolerance and exhaustion, thus raising the effectiveness of immune therapy in mice. Based on these novel insights, it may be proposed that regulation of Nur77 activity holds promise for innovative drug development in the field of cellular immunotherapy in cancer. In this review, we therefore summarize the role of Nur77 in T cell selection and maturation; and further develop the idea of targeting its activity in these cells as a potential strategy to augment current cancer immunotherapy treatments.  相似文献   
996.
《Immunobiology》2020,225(3):151959
AimsNeuromyelitis optica spectrum disorders (NMOSD) are aquaporin-4 antibody-mediated diseases of the central nervous system. Endothelin-1 (ET-1) is an inflammatory cytokine released by vascular endothelial cells and activated astrocytes. Previous studies have reported the aberrant expressions of cytokines/chemokines in patients diagnosed with NMOSD. However, the serum levels of ET-1 in NMOSD patients remain unknown. The purpose of this study was to measure the serum levels of ET-1 and other immune-related cytokines/chemokines in patients with NMOSD, and to investigate the correlation between serum ET-1 levels and clinical characteristics of NMOSD.MethodsThirty-eight patients with NMOSD and twenty-eight healthy controls (HCs) were recruited in this study. The serum concentrations of ET-1 and other cytokines/chemokines were measured, and their correlations to the clinical features of patients with NMOSD were analyzed.ResultsThe serum levels of ET-1 in patients with NMOSD were significantly higher than those in HCs (P = 0.0001). The serum concentrations of ET-1 were positively correlated with the Expanded Disability Status Scale score (r = 0.428, P = 0.0183). High-dose intravenous methylprednisolone treatment significantly reduced the levels of ET-1 and interleukin (IL)-6 in blood, but significantly increased the serum concentrations of IL-10 in NMOSD patients. No correlations were found between serum ET-1 levels and the concentrations of other cytokines/chemokines in these patients.ConclusionET-1 and IL-6 might exert pro-inflammatory effects in the pathogenesis of NMOSD, whereas IL-10 played an anti-inflammatory role in this process. ET-1 might be a potential biomarker for predicting the severity of NMOSD. However, the serum levels of ET-1 were not correlated with the changes of other cytokines/chemokines in patients with NMOSD. The involvement of ET-1 in the development of NMOSD needs to be further studied.  相似文献   
997.
《Vaccine》2020,38(44):6941-6953
Addressing vaccine management bottlenecks, including high vaccine wastage rates, has traditionally been addressed through health worker training and other didactic methods of technical assistance or support as required. It has been shown, though, that the high level of technical skills, expertise, and responsibility required in vaccine handling and management cannot be achieved by mere didactic learning. While gains have been made in vaccine management and handling with these approaches, there remain challenges of high vaccine wastage rates and poor vaccine management practices across the board. Interestingly, approaching vaccine management through social behavior change has not been documented. Through Participatory Action Research (PAR), which is increasingly being used in health sciences, we explore an attempt at strengthening vaccine management and thus reducing high vaccine wastage rates by working together with health workers to identify plausible, realistic solutions to vaccine management through social behavior change. Select health workers directly involved with the immunization program in the four major provinces of the Solomon Islands were identified purposively to use action media and come up with concepts and materials for social behavior change communication that will have an impact on effective vaccine management and reducing wastages. This is the first documented use of such methodology in addressing vaccine management issues.  相似文献   
998.
ObjectivesThis study aimed to determine the impact of the approval of prothrombin complex concentrates on the treatment of vitamin K antagonist-related intracerebral hemorrhage.Materials and MethodsWe retrospectively studied all patients with vitamin K antagonist-related intracerebral hemorrhage treated with prothrombin complex concentrate at our institutes between January 2010 and June 2021. Before approval, prothrombin complex concentrate was administered as either 500 or 1000 IU at the physician's discretion (previous dose group). After approval, we adopted the manufacturer's recommended regimen (recommended dose group). The primary outcome was post-administration international normalized ratio. Secondary outcomes were the amount of prothrombin complex concentrate administered and proportion of post-administration international normalized ratio <1.5, hematoma expansion, thrombotic events within 30 days, modified Rankin scale 0–3 at discharge, and in-hospital mortality.ResultsThirty-two and 19 patients in the previous and recommended dose groups, respectively, were included. The post-administration international normalized ratio significantly differed between groups. The prothrombin complex concentrate dose and proportion of patients achieving post-administration international normalized ratio <1.5 were significantly higher in the recommended dose group than in the previous dose group (1500 IU vs. 500 IU, p<0.001 and 100% vs. 68%, p = 0.008). The proportions of hematoma expansion, thromboembolic events, modified Rankin scale 0-3, and mortality did not differ between groups.ConclusionAfter prothrombin complex concentrate approval, prothrombin time-international normalized ratio correction was more effective with a significant increase in the prothrombin complex concentrates dose for vitamin K antagonist-associated intracerebral hemorrhage; however, there was no apparent difference in clinical outcomes.  相似文献   
999.
目的比较硫酸钙介导的诱导膜(Masquelet)技术与常规的Masquelet技术治疗成人胫骨大段骨缺损的早期临床疗效。方法回顾性分析2013年1月至2017年5月我院收治的39例成人胫骨大段骨缺损患者:硫酸钙介导的Masquelet技术治疗的23例纳入硫酸钙组,男15例,女8例,骨缺损长度为(7.3±1.8)cm;常规的Masquelet技术治疗的16例纳入常规组,男12例,女4例,骨缺损长度为(7.4±1.9) cm。收集并比较两组病例的骨愈合时间、完全负重时间、术后并发症情况及末次随访时的Iowa膝关节评分、Iowa踝关节评分、健康状况调查问卷(SF-36)得分。结果 39例患者的随访时间为11~36个月,平均(20.5±7.5)个月。硫酸钙组与常规组的骨愈合时间分别为(20.85±4.31)周、(28.86±6.47)周,完全负重时间分别为(23.17±6.93)周、(32.87±6.79)周,两组间比较,差异均有统计学意义(t=4.944,P0.000 1;t=4.636,P0.000 1);两组末次随访时的Iowa膝、踝关节评分及SF-36量表总得分均较术前明显改善,但两组间比较,差异均无统计学意义(P均0.05)。结论硫酸钙介导的Masquelet技术与常规的Masquelet技术均可有效地解决成人胫骨大段骨缺损清创后大段骨缺损问题,但硫酸钙介导的Masquelet技术能显著缩短治疗周期,完全负重时间早,是一种简单有效的手术方法。  相似文献   
1000.
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