全文获取类型
收费全文 | 12171篇 |
免费 | 968篇 |
国内免费 | 568篇 |
专业分类
耳鼻咽喉 | 44篇 |
儿科学 | 249篇 |
妇产科学 | 65篇 |
基础医学 | 496篇 |
口腔科学 | 81篇 |
临床医学 | 715篇 |
内科学 | 784篇 |
皮肤病学 | 98篇 |
神经病学 | 359篇 |
特种医学 | 206篇 |
外国民族医学 | 7篇 |
外科学 | 633篇 |
综合类 | 1273篇 |
预防医学 | 1115篇 |
眼科学 | 237篇 |
药学 | 4562篇 |
1篇 | |
中国医学 | 1200篇 |
肿瘤学 | 1582篇 |
出版年
2023年 | 153篇 |
2022年 | 214篇 |
2021年 | 280篇 |
2020年 | 382篇 |
2019年 | 404篇 |
2018年 | 394篇 |
2017年 | 482篇 |
2016年 | 510篇 |
2015年 | 420篇 |
2014年 | 672篇 |
2013年 | 1215篇 |
2012年 | 718篇 |
2011年 | 768篇 |
2010年 | 590篇 |
2009年 | 612篇 |
2008年 | 588篇 |
2007年 | 617篇 |
2006年 | 526篇 |
2005年 | 457篇 |
2004年 | 413篇 |
2003年 | 357篇 |
2002年 | 295篇 |
2001年 | 268篇 |
2000年 | 207篇 |
1999年 | 187篇 |
1998年 | 156篇 |
1997年 | 162篇 |
1996年 | 140篇 |
1995年 | 149篇 |
1994年 | 150篇 |
1993年 | 146篇 |
1992年 | 117篇 |
1991年 | 82篇 |
1990年 | 98篇 |
1989年 | 86篇 |
1988年 | 101篇 |
1987年 | 59篇 |
1986年 | 40篇 |
1985年 | 93篇 |
1984年 | 71篇 |
1983年 | 71篇 |
1982年 | 60篇 |
1981年 | 32篇 |
1980年 | 38篇 |
1979年 | 19篇 |
1978年 | 25篇 |
1977年 | 15篇 |
1976年 | 27篇 |
1975年 | 15篇 |
1973年 | 7篇 |
排序方式: 共有10000条查询结果,搜索用时 31 毫秒
1.
2.
《Revista portuguesa de cardiologia》2022,41(9):783-789
Amiodarone is the most potent antiarrhythmic drug available and is commonly prescribed to treat and prevent not only life-threatening ventricular arrhythmias but also atrial fibrillation (AF). The latest European Society of Cardiology AF guidelines state that amiodarone is recommended for long-term rhythm control in all AF patients but that other antiarrhythmic drugs should be considered first whenever possible, due to its extracardiac toxicity. In patients without significant or with only minimal structural heart disease, amiodarone is not listed as a possibility in their therapeutic scheme. Still, amiodarone is widely and liberally used, and is the most prescribed antiarrhythmic drug for patients with AF despite its high toxicity profile. Non-cardiovascular death was more frequent with amiodarone treatment than with a rate control strategy in AFFIRM, while meta-analyses suggest an association between amiodarone use in patients without structural heart disease and increased non-cardiovascular mortality. Severe or even fatal outcomes due to amiodarone may occur years after treatment initiation and are often not acknowledged by the prescribing physician, who may no longer be following the patient. The lack of widely accepted diagnostic criteria and symptom definitions may lead to underestimation of the incidence of severe side effects and of its toxicity. Unlike the underestimated risk of toxicity with amiodarone, severe complications associated with catheter ablation are usually directly ascribed to the treatment even by non-medical personnel, possibly resulting in overestimation of risks. This brief review will address the issue of amiodarone overuse and the frequent underestimation of its toxicity, while suggesting scenarios in which its use is entirely reasonable, and compare it with catheter ablation. 相似文献
3.
《Survey of ophthalmology》2023,68(5):1006-1010
A 23-year-old previously healthy woman presented with headache, generalized seizures, ataxia, encephalopathy, abdominal pain, nausea, and vomiting culminating in a 40-pound weight loss. A contrasted magnetic resonance imaging scan of the brain showed T2/FLAIR hyperintensities in the sulci of the occipital and parietal lobes, a punctate focus of restricted diffusion along the inferior aspect of the left caudate head and an empty sella. A lumbar puncture showed an opening pressure of 55 cm H2O, and kidney, ureter, and bladder X ray showed a radiopaque particle in the colon. Serum lead level was 85 mcg/dL (< 3.5). Blood smear showed foreign bodies identified as lead particles in the blood with basophilic stippling of RBCs. She was treated with chelation therapy and bowel irrigation and eventually recovered. Further investigation indicated that she was being slowly poisoned by her husband, a chiropractor who had access to lead. 相似文献
4.
Rapid industrial and technological development has impacted ecosystem homeostasis strongly. Arsenic is one of the most detrimental environmental toxins and its management with chelating agents remains a matter of concern due to associated adverse effects. Thus, safer and more effective alternative therapy is required to manage arsenic toxicity. Based on existing evidence, native and indigenous plant-based active biomolecules appear as a promising strategy to mitigate arsenic-induced toxicity with an acceptable safety profile. In this regard, various phytochemicals (flavonoids and stilbenoids) are considered important classes of polyphenolic compounds with antioxidant and chelation effects, which may facilitate the removal of arsenic from the body more effectively and safely with regard to conventional approaches. This review presents an overview of conventional chelating agents and the potential role of flavonoids and stilbenoids in ameliorating arsenic toxicity. This report may provide a roadmap for identifying novel prophylactic/therapeutic strategies for managing arsenic toxicity. 相似文献
5.
目的分析维生素D(vitamin D, VitD)在降低PM2.5对肺泡上皮细胞毒性中的影响。 方法采用透射电子显微镜和激光诱导荧光分析对比VitD处理前后,PM2.5的毒性能力。MMT观察VitD处理前后细胞生存率,分析PM2.5对A549的毒性影响。 结果VitD作用后的PM2.5平均粒径减小5.5 nm,颗粒聚结和团聚更为明显,颗粒平均条纹长度增加、弯曲度减小,差异有统计学意义。PM2.5条纹间距无统计学差异,有明显减小,接近0.06 nm。VitD溶液从PM2.5解吸3环和4环多环芳香烃(polycyclic aromatic hydrocarbons, PAHs),减少PM2.5表面附着的致病性PAHs。PM2.5可引起肺上皮细胞A549生存率明显下降,给予VitD干预后,PM2.5对A549细胞生存率的抑制改善了54.7%,PM2.5的生物毒性降低。 结论VitD可减少PM2.5上吸附的致病性PAHs,抑制其致病活性,减小PM2.5对肺上皮细胞的毒性。 相似文献
6.
目的 了解膀胱癌输尿管皮肤造口患者经济毒性现状并分析其影响因素,为探索干预策略提供参考。方法 采用便利抽样法抽取就诊于伤口造口门诊的130例输尿管皮肤造口患者,采用一般资料调查表、患者报告结局的经济毒性综合评分量表、恐惧疾病进展简化量表、患者健康问卷抑郁量表进行调查。结果 输尿管皮肤造口患者经济毒性发生率为86.15%,经济毒性总分为23.00(17.00,25.00)分;相关性分析结果显示,恐惧疾病进展水平、抑郁水平与经济毒性呈正相关(均P<0.01);多元线性回归结果显示,恐惧疾病进展、抑郁、年龄、家庭人均月收入、医保类型、到达医疗机构的乘车时间是患者经济毒性的影响因素(P<0.05,P<0.01)。结论 输尿管皮肤造口患者经济毒性阳性率较高,在临床工作中应特别关注年轻、低收入、未参保、到达医疗机构的乘车时间较长的输尿管皮肤造口患者经济毒性的评估,对高危患者进行早期干预,防止因经济毒性引起不良结局事件。 相似文献
7.
Sharon Elad DMD MSc Noam Yarom DMD Yehuda Zadik DMD MHA Michal Kuten-Shorrer DMD DMSc Stephen T. Sonis DMD DMSc 《CA: a cancer journal for clinicians》2022,72(1):57-77
Oral mucositis (OM) is a common, highly symptomatic complication of cancer therapy that affects patients' function, quality of life, and ability to tolerate treatment. In certain patients with cancer, OM is associated with increased mortality. Research on the management of OM is ongoing. Oral mucosal toxicities are also reported in targeted and immune checkpoint inhibitor therapies. The objective of this article is to present current knowledge about the epidemiology, pathogenesis, assessment, risk prediction, and current and developing intervention strategies for OM and other ulcerative mucosal toxicities caused by both conventional and evolving forms of cancer therapy. 相似文献
8.
Xinwen Zhang Delphis F. Levia Elvis Osamudiamhen Ebikade Jeffrey Chang Dionisios G. Vlachos Changqing Wu 《Journal of applied toxicology : JAT》2022,42(3):423-435
Lignin and lignin-based materials have received considerable attention in various fields due to their promise as sustainable feedstocks. Guaiacol (G) and syringol (S) are two primary monolignols that occur in different ratios for different plant species. As methoxyphenols, G and S have been targeted as atmospheric pollutants and their acute toxicity examined. However, there is a rare understanding of the toxicological properties on other endpoints and mixture effects of these monolignols. To fill this knowledge gap, our study investigated the impact of different S/G ratios (0.5, 1, and 2) and three lignin depolymerization samples from poplar, pine, and miscanthus species on mutagenicity and developmental toxicity. A multitiered method consisted of in silico simulation, in vitro Ames test, and in vivo chicken embryonic assay was employed. In the Ames test, syringol showed a sign of mutagenicity, whereas guaiacol did not, which agreed with the T.E.S.T. simulation. For three S and G mixture and lignin monomers, mutagenic activity was related to the proportion of syringol. In addition, both S and G showed developmental toxicity in the chicken embryonic assay and T.E.S.T. simulation, and guaiacol had a severe effect on lipid peroxidation. A similar trend and comparable developmental toxicity levels were detected for S and G mixtures and the three lignin depolymerized monomers. This study provides data and insights on the differential toxicity of varying S/G ratios for some important building blocks for bio-based materials. 相似文献
9.
毒性中药饮片的安全性、有效性与质量可控性是中医药传承与创新的核心,而炮制工艺的科学合理是保证毒性中药饮片应用安全有效的关键。本文概述了毒性中药饮片发展过程及质量控制现状,并对其存在的问题进行分析总结。毒性中药主要通过加工炮制达到减毒增效的目的以保障临床安全有效,因此针对毒性中药饮片炮制现状进行综述,系统梳理了古今毒性中药饮片炮制工艺,初步阐述了毒性中药饮片炮制减毒机制。在此基础之上,针对毒性中药饮片炮制研究,提出基于中医药整体观系统开展炮制过程动态变化规律研究,基于中医药和谐观解析炮制过程中物质相互作用科学内涵,为明晰毒性中药饮片炮制机制,规范毒性中药饮片炮制工艺,实现毒性中药饮片质量控制,保障毒性中药饮片临床安全有效提供参考借鉴。 相似文献
10.
Preliminary study on blood coagulation and hemostatic effect and acute toxicity of Oxalis corniculata L. ethanol extract 下载免费PDF全文
In the present study, we aimed to observe the effects of ethanol extract of Oxalis corniculata L. on bleeding time (BT) and coagulation time (CT) and determine its acute toxicity in mice. Firstly, the ethanol extract of O. corniculata was administered to 40 mice, which were randomly divided into the normal control group, Yunnan Baiyao control group, low-dose group, and high-dose group. The low-dose (0.6 g/kg) and high-dose (1.2 g/kg) groups received ethanol extract of O. corniculata by gavage, and the BT and CT of the mice were measured by the slide method and tail clipping method, respectively. Secondly, the median lethal dose method was used with 50 mice to observe the physiological state, poisoning reaction, and death of the mice after intragastric administration. Finally, on the 14th day of the experiment, a necropsy was performed to observe any abnormality of the organs. In conclusion, in the coagulation and hemostasis tests, there were no statistical differences between the groups (P > 0.05), while there was a significant dose-response relationship, and the BT and CT were significantly shorter than those of the negative control group, which were comparable to the Yunnan Baiyao control group. Moreover, in the acute toxicity test, the median lethal dose of ethanol extract of O. corniculata was 6.0291 g/kg, with a 95% confidence interval of 5.3065–6.7829 mg/kg. 相似文献