首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   2904650篇
  免费   249945篇
  国内免费   12883篇
耳鼻咽喉   40094篇
儿科学   93434篇
妇产科学   72908篇
基础医学   480339篇
口腔科学   76354篇
临床医学   263081篇
内科学   492537篇
皮肤病学   83823篇
神经病学   247729篇
特种医学   115264篇
外国民族医学   79篇
外科学   461295篇
综合类   88855篇
现状与发展   24篇
一般理论   2100篇
预防医学   244332篇
眼科学   66835篇
药学   197093篇
  17篇
中国医学   8852篇
肿瘤学   132433篇
  2021年   55403篇
  2020年   35284篇
  2019年   58266篇
  2018年   71037篇
  2017年   53625篇
  2016年   59115篇
  2015年   73504篇
  2014年   107928篇
  2013年   173048篇
  2012年   79651篇
  2011年   78868篇
  2010年   114528篇
  2009年   118933篇
  2008年   64371篇
  2007年   66269篇
  2006年   76841篇
  2005年   72438篇
  2004年   74442篇
  2003年   65638篇
  2002年   55575篇
  2001年   72752篇
  2000年   64220篇
  1999年   70328篇
  1998年   61896篇
  1997年   60366篇
  1996年   58064篇
  1995年   53537篇
  1994年   47538篇
  1993年   44602篇
  1992年   46932篇
  1991年   46152篇
  1990年   43629篇
  1989年   43759篇
  1988年   40543篇
  1987年   39767篇
  1986年   37613篇
  1985年   38630篇
  1984年   38103篇
  1983年   35612篇
  1982年   37428篇
  1981年   35654篇
  1980年   33730篇
  1979年   30281篇
  1978年   29056篇
  1977年   26818篇
  1976年   25033篇
  1975年   24111篇
  1974年   23529篇
  1973年   22545篇
  1972年   21099篇
排序方式: 共有10000条查询结果,搜索用时 421 毫秒
991.
目的:特应性皮炎的发病及治疗存在很大的异质性,在治疗方面特别强调个体化治疗,本文主要总结成年女性特应性皮炎的治疗思路和方法。方法:基于肝脾两脏的生理、病理及成年女性特应性皮炎的临床表现,深入分析其病因病机及治疗方法。结果:女性成年特应性皮炎患者常肝脾同病,肝郁脾虚湿蕴和肝郁脾虚血弱是成年女性特应性皮炎的常见证型,临床可采用疏肝健脾祛湿法和疏肝健脾养血法进行治疗。典型病例中采用肝脾同调法不但可以改善患者的皮疹,也可有效缓解瘙痒和不良情绪。结论:肝脾同调法是治疗成年女性特应性皮炎的有效方法。  相似文献   
992.
In May 2017, the Health and Environmental Sciences Institute's Genetic Toxicology Technical Committee hosted a workshop to discuss whether mode of action (MOA) investigation is enhanced through the application of the adverse outcome pathway (AOP) framework. As AOPs are a relatively new approach in genetic toxicology, this report describes how AOPs could be harnessed to advance MOA analysis of genotoxicity pathways using five example case studies. Each of these genetic toxicology AOPs proposed for further development includes the relevant molecular initiating events, key events, and adverse outcomes (AOs), identification and/or further development of the appropriate assays to link an agent to these events, and discussion regarding the biological plausibility of the proposed AOP. A key difference between these proposed genetic toxicology AOPs versus traditional AOPs is that the AO is a genetic toxicology endpoint of potential significance in risk characterization, in contrast to an adverse state of an organism or a population. The first two detailed case studies describe provisional AOPs for aurora kinase inhibition and tubulin binding, leading to the common AO of aneuploidy. The remaining three case studies highlight provisional AOPs that lead to chromosome breakage or mutation via indirect DNA interaction (inhibition of topoisomerase II, production of cellular reactive oxygen species, and inhibition of DNA synthesis). These case studies serve as starting points for genotoxicity AOPs that could ultimately be published and utilized by the broader toxicology community and illustrate the practical considerations and evidence required to formalize such AOPs so that they may be applied to genetic toxicity evaluation schemes. Environ. Mol. Mutagen. 61:114–134, 2020. © 2019 Wiley Periodicals, Inc.  相似文献   
993.
ObjectiveStimulation of the dorsal spinal roots, or spinal nerve root stimulation (SNRS), is a neuromodulation modality that can target pain within specific dermatomal distributions. The use of paresthesia-free stimulation has been described with conventional dorsal column spinal cord stimulation, although has yet to be described for SNRS. This objective of this study was to investigate the efficacy of paresthesia-free high-frequency (1000–1200 Hz) SNRS in the treatment of intractable, dermatomal neuropathic pain.Materials and MethodsA retrospective chart review was performed on 14 patients implanted with SNRS in varying distributions: Ten patients initially received tonic stimulation and crossed over to a paresthesia-free paradigm and four patients received only paresthesia-free stimulation. The primary outcome was reduction in pain severity (visual analog scale [VAS]), measured at baseline and follow-up to 24 months with paresthesia-free stimulation.ResultsAll 14 patients who received paresthesia-free stimulation had significant improvement in pain severity at a mean follow-up of 1.39 ± 0.15 years (VAS 7.46 at baseline vs. 3.25 at most recent follow-up, p < 0.001). Ten patients were initially treated with tonic stimulation and crossed over to paresthesia-free stimulation after a mean of 61.7 months. Baseline pain in these crossover patients was significantly improved at last follow-up with tonic stimulation (VAS 7.65 at baseline vs. 2.83 at 48 months, p < 0.001), although all patients developed uncomfortable paresthesias. There was no significant difference in pain severity between patients receiving tonic and paresthesia-free stimulation.ConclusionsWe present real-world outcomes of patients with intractable dermatomal neuropathic pain treated with paresthesia-free, high-frequency SNRS. We demonstrate its effectiveness in providing pain reduction at a level comparable to tonic SNRS up to 24 months follow-up, without producing uncomfortable paresthesias.  相似文献   
994.
995.
996.
997.
Phone use is a critical communication event in many people''s lives. Audiologists have aimed to assist individuals with hearing loss and phone usage through the use of technology and counseling. To counsel effectively, all contributions to hearing difficulty on the phone must be considered, including the effects of smartphone cases. The purpose of this study was to evaluate the effects on dB output caused by waterproof smartphone cases that cover the ear-level speaker. One waterproof case was tested with three smartphones, two iPhones, and one Android. A second waterproof case was tested with the two iPhones. Results revealed there was significant attenuation of the audio-signal by both waterproof smartphone cases that was great enough in one case/phone combination to potentially result in a complete lack of intelligibility of the signal.  相似文献   
998.
999.
1000.
In this review we summarize the impact of the various modalities of breast cancer therapy coupled with intrinsic patient factors on incidence of subsequent treatment-induced myelodysplasia and acute myelogenous leukemia (t-MDS/AML). It is clear that risk is increased for patients treated with radiation and chemotherapy at younger ages. Radiation is associated with modest risk, whereas chemotherapy, particularly the combination of an alkylating agent and an anthracycline, carries higher risk and radiation and chemotherapy combined increase the risk markedly. Recently, treatment with granulocyte colony-stimulating factor (G-CSF), but not pegylated G-CSF, has been identified as a factor associated with increased t-MDS/AML risk. Two newly identified associations may link homologous DNA repair gene deficiency and poly (ADP-ribose) polymerase inhibitor treatment to increased t-MDS/AML risk. When predisposing factors, such as young age, are combined with an increasing number of potentially leukemogenic treatments that may not confer large risk singly, the risk of t-MDS/AML appears to increase. Patient and treatment factors combine to form a biological cascade that can trigger a myelodysplastic event. Patients with breast cancer are often exposed to many of these risk factors in the course of their treatment, and triple-negative patients, who are often younger and/or BRCA positive, are often exposed to all of them. It is important going forward to identify effective therapies without these adverse associated effects and choose existing therapies that minimize the risk of t-MDS/AML without sacrificing therapeutic gain.

Implications for Practice

Breast cancer is far more curable than in the past but requires multimodality treatment. Great care must be taken to use the least leukemogenic treatment programs that do not sacrifice efficacy. Elimination of radiation and anthracycline/alkylating agent regimens will be helpful where possible, particularly in younger patients and possibly those with homologous repair deficiency (HRD). Use of colony-stimulating factors should be limited to those who truly require them for safe chemotherapy administration. Further study of a possible leukemogenic association with HRD and the various forms of colony-stimulating factors is badly needed.
  相似文献   
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号