全文获取类型
收费全文 | 371809篇 |
免费 | 21301篇 |
国内免费 | 12791篇 |
专业分类
耳鼻咽喉 | 2892篇 |
儿科学 | 8752篇 |
妇产科学 | 5558篇 |
基础医学 | 39501篇 |
口腔科学 | 5167篇 |
临床医学 | 38480篇 |
内科学 | 59038篇 |
皮肤病学 | 3143篇 |
神经病学 | 26298篇 |
特种医学 | 15747篇 |
外国民族医学 | 99篇 |
外科学 | 48530篇 |
综合类 | 35605篇 |
现状与发展 | 47篇 |
一般理论 | 27篇 |
预防医学 | 31864篇 |
眼科学 | 7990篇 |
药学 | 31265篇 |
216篇 | |
中国医学 | 13300篇 |
肿瘤学 | 32382篇 |
出版年
2024年 | 864篇 |
2023年 | 3435篇 |
2022年 | 8915篇 |
2021年 | 11165篇 |
2020年 | 8527篇 |
2019年 | 7161篇 |
2018年 | 28758篇 |
2017年 | 23886篇 |
2016年 | 25408篇 |
2015年 | 10648篇 |
2014年 | 12559篇 |
2013年 | 11777篇 |
2012年 | 22684篇 |
2011年 | 37586篇 |
2010年 | 29523篇 |
2009年 | 19858篇 |
2008年 | 30307篇 |
2007年 | 31793篇 |
2006年 | 10359篇 |
2005年 | 11579篇 |
2004年 | 9363篇 |
2003年 | 9734篇 |
2002年 | 7003篇 |
2001年 | 4144篇 |
2000年 | 4392篇 |
1999年 | 4136篇 |
1998年 | 2523篇 |
1997年 | 2572篇 |
1996年 | 1896篇 |
1995年 | 1858篇 |
1994年 | 1624篇 |
1993年 | 983篇 |
1992年 | 1365篇 |
1991年 | 1224篇 |
1990年 | 1046篇 |
1989年 | 943篇 |
1988年 | 832篇 |
1987年 | 677篇 |
1986年 | 501篇 |
1985年 | 445篇 |
1984年 | 232篇 |
1983年 | 202篇 |
1982年 | 127篇 |
1981年 | 130篇 |
1980年 | 126篇 |
1979年 | 121篇 |
1978年 | 69篇 |
1977年 | 66篇 |
1974年 | 74篇 |
1938年 | 60篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
121.
目的 探究黄石、荆门地区产后妇女母乳喂养自我效能的现状及影响因素,为改善母乳喂养率提供更多理论依据。方法 对2017年12月—2018年3月在湖北省黄石市、荆门市的三所医院住院分娩的产妇进行问卷调查,获得产妇社会人口特征、孕产相关资料、母乳喂养相关情况。采用多元线性回归分析母乳喂养自我效能的影响因素。结果 共1 023名产妇纳入分析,平均年龄(29.0±5.7)岁。已婚占98.3%,初产占54.0%,大专及以上学历占53.9%。研究对象的母乳喂养自我效能平均得分为(45.5±12.3)分。多元线性回归的结果显示:当前不存在乳腺问题(B=2.08,P=0.036)、有母乳喂养经历(B=3.62,P<0.001)、家人提供母乳喂养指导或经验(B=3.20,P=0.001)、丈夫支持母乳喂养(B=5.87,P=0.001)及产后30 min内有医护母乳喂养帮助(B=3.02,P=0.003)的产妇母乳喂养自我效能得分更高。结论 产后妇女的母乳喂养自我效能可能与其健康状况、母乳喂养经历、社会支持及母乳喂养卫生服务有关。应对产后妇女提供广泛的社会支持,加强母乳喂养卫生服务提供,以提高其母乳喂养的自我效能,促进母乳喂养。 相似文献
122.
ABSTRACT Most senior veterans who live in veteran homes in Taiwan have few interpersonal relationships. Aging is often accompanied by solitude and illness, which causes senior veterans to doubt the meaning of life and to lose confidence in the value of life. This study tested the effectiveness of a group reminiscence therapy protocol on the depression and meaning of life among elderly institutionalized veterans. A quasi-experimental design was applied. A convenience sample of older adults was drawn from two veteran homes in southern Taiwan. Participants were assigned to intervention or control groups based on the veterans' homes they attended. The participants in the intervention group carried out group reminiscence therapy for 8 weeks in addition to their daily activities. The participants in the comparison group maintained their daily activities. Both groups were evaluated using the GDS-SF and MLS scale including two aspects of depression mood and meaning of life in weeks 1 and 8. The overall life satisfaction increased significantly over time for the intervention group compared to the comparison group from week 1 to week 8. The group reminiscence therapy programs showed promising effects in improving the depression and meaning of life of older veterans living in veteran homes. 相似文献
123.
124.
125.
126.
127.
J. Yang S. Gohel Z. Zhang V. Hatzoglou A.I. Holodny B.A. Vachha 《AJNR. American journal of neuroradiology》2021,42(3):551
BACKGROUND AND PURPOSE:Cognitive challenges are prevalent in survivors of glioma, but their neurobiology is incompletely understood. The purpose of this study was to investigate the effect of glioma presence and tumor characteristics on resting-state functional connectivity and amplitude of low-frequency fluctuations of the salience network, a key neural network associated with cognition.MATERIALS AND METHODS:Sixty-nine patients with glioma (mean age, 48.74 [SD, 14.32] years) who underwent resting-state fMRI were compared with 31 healthy controls (mean age, 49.68 [SD, 15.54] years). We identified 4 salience network ROIs: left/right dorsal anterior cingulate cortex and left/right anterior insula. Average salience network resting-state functional connectivity and amplitude of low-frequency fluctuations within the 4 salience network ROIs were computed.RESULTS:Patients with gliomas showed decreased overall salience network resting-state functional connectivity (P = .001) and increased amplitude of low-frequency fluctuations in all salience network ROIs (P < .01) except in the left dorsal anterior cingulate cortex. Compared with controls, patients with left-sided gliomas showed increased amplitude of low-frequency fluctuations in the right dorsal anterior cingulate cortex (P = .002) and right anterior insula (P < .001), and patients with right-sided gliomas showed increased amplitude of low-frequency fluctuations in the left anterior insula (P = .002). Anterior tumors were associated with decreased salience network resting-state functional connectivity (P < .001) and increased amplitude of low-frequency fluctuations in the right anterior insula, left anterior insula, and right dorsal anterior cingulate cortex. Patients with high-grade gliomas had decreased salience network resting-state functional connectivity compared with healthy controls (P < .05). The right anterior insula showed increased amplitude of low-frequency fluctuations in patients with grade II and IV gliomas compared with controls (P < .01).CONCLUSIONS:By demonstrating decreased resting-state functional connectivity and an increased amplitude of low-frequency fluctuations related to the salience network in patients with glioma, this study adds to our understanding of the neurobiology underpinning observable cognitive deficits in these patients. In addition to more conventional functional connectivity, amplitude of low-frequency fluctuations is a promising functional-imaging biomarker of tumor-induced vascular and neural pathology.Detrimental effects of cancer on cognitive function and, consequently, on the quality of life are emerging as a key focus of cancer survivorship both in research and clinical practice.1,2 Brain tumors have been shown to affect memory, processing, and attention in patients; however, their underlying neurobiology is incompletely understood.3 Using resting-state functional MR imaging (rsfMRI) to evaluate changes in cognitive resting-state networks may provide a better understanding of the pathology underlying the observable cognitive disruptions in gliomas, the most common primary brain tumor in adults.A “triple network model” of neurocognitive pathology has been proposed, which encompasses the default mode network, involved in mind wandering; the central executive network, involved in decision-making; and the salience network (SN), implicated in modulating activation of the default mode network and central executive network by detecting the presence of salient stimuli.4-8 While previous rsfMRI research has largely focused on tumor-induced changes in the default mode network,9,10 our study examined the less-studied SN, a network rooted in the anterior insula and the dorsal anterior cingulate cortex.6Prior studies evaluating gliomas and SN resting-state functional connectivity (RSFC) provided conflicting results in small patient samples: Maesawa et al10 found no significant differences in the SN in 12 patients, while Liu et al11 more recently found decreased SN connectivity in 13 patients. Gliomas impact the integrity of the neurovascular unit to varying degrees, resulting in neurovascular uncoupling that has been reported to confound fMRI interpretations in patients with brain tumors.12-14 Additionally, research has reported neuronal plasticity manifested by structural reorganization and functional remodeling of neural networks in patients with gliomas with possible alterations in clinically observable cognitive manifestations.15-17 An rsfMRI metric, the amplitude of low-frequency fluctuations (ALFF), has recently shown promise as a biomarker for brain plasticity and hemodynamic characterization, including neurovascular uncoupling in patients with gliomas.15-19The purpose of this study was to investigate the effect of glioma presence and tumor characteristics on overall RSFC and regional normalized ALFF within the SN in a large patient population. We hypothesized that there would be decreased average SN RSFC and altered ALFF in patients with gliomas compared with healthy controls. Recent studies have acknowledged that gliomas have variable effects on network integrity based on lesion location and proximity to network ROIs,20-22 and unilateral gliomas can be associated with plasticity in both the ipsilateral and contralateral hemispheres.11,17 Research also supports differences in resting-state network reorganization in aggressive high-grade gliomas compared with slower-growing low-grade gliomas.20,23 Therefore, we also hypothesized that there would be differences in average SN RSFC and regional ALFF in patients based on the anterior-versus-posterior location, hemispheric side, and grade of glioma. 相似文献
128.
129.
Bryan E.K. Guevara Suhail Saleem Wan‐Ting Chen Pa‐Fan Hsiao Yu‐Hung Wu 《Journal of cutaneous pathology》2019,46(5):347-352
Lucio phenomenon is an atypical reaction of leprosy, characterized by vasculitic lesions that can mimic antiphospholipid syndrome (APS) clinically. Distinguishing the two can be difficult as antiphospholipid autoantibodies may be present in patients with leprosy. We report on a 32‐year‐old female patient presenting with a sudden onset of fever, hemorrhagic bullae, and skin necrosis on her lower legs. She was treated for APS due to the presence of antiphospholipid antibodies but had an inadequate response. A skin biopsy revealed thrombotic vasculopathy and necrotizing vasculitis associated with aggregation of foam cells in the perivascular area and subcutis, with acid‐fast bacilli in the histiocytes and blood vessel walls. Direct immunofluorescence showed IgM, C3, and fibrinogen deposition in the superficial and deep dermal blood vessels. The pathology confirmed the diagnosis of Lucio phenomenon, and appropriate therapy was given. It is essential to evaluate the patient comprehensively, including clinical, serological, and pathological aspects, to obtain the correct diagnosis. 相似文献
130.