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   34303篇
  免费   1915篇
  国内免费   417篇
耳鼻咽喉   190篇
儿科学   315篇
妇产科学   440篇
基础医学   2626篇
口腔科学   429篇
临床医学   3755篇
内科学   4236篇
皮肤病学   302篇
神经病学   3030篇
特种医学   1039篇
外国民族医学   292篇
外科学   1893篇
综合类   6253篇
一般理论   2篇
预防医学   2840篇
眼科学   180篇
药学   3725篇
  9篇
中国医学   1934篇
肿瘤学   3145篇
  2023年   214篇
  2022年   390篇
  2021年   682篇
  2020年   656篇
  2019年   598篇
  2018年   770篇
  2017年   638篇
  2016年   617篇
  2015年   651篇
  2014年   4907篇
  2013年   3870篇
  2012年   2914篇
  2011年   2755篇
  2010年   3964篇
  2009年   3714篇
  2008年   1914篇
  2007年   904篇
  2006年   796篇
  2005年   630篇
  2004年   569篇
  2003年   510篇
  2002年   372篇
  2001年   392篇
  2000年   300篇
  1999年   320篇
  1998年   247篇
  1997年   243篇
  1996年   231篇
  1995年   203篇
  1994年   184篇
  1993年   132篇
  1992年   139篇
  1991年   120篇
  1990年   113篇
  1989年   86篇
  1988年   98篇
  1987年   81篇
  1986年   65篇
  1985年   106篇
  1984年   101篇
  1983年   66篇
  1982年   79篇
  1981年   53篇
  1980年   43篇
  1979年   45篇
  1978年   28篇
  1977年   32篇
  1976年   28篇
  1975年   14篇
  1973年   14篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
1.
《Vaccine》2022,40(23):3236-3243
BackgroundInfections can have a significant impact on morbidity and mortality in multiple sclerosis (MS) patients. Therefore, vaccinations are of immense importance. If vaccination willingness is to be increased, possible influencing factors should be identified. The aim of the present study was to investigate the status of active immunisation in MS patients in association with sociodemographic, clinical-neurological, psychopathological and personality variables using the NEO-Five Factor Inventory, the Temperament and Character Inventory-Revised and the Hospital Anxiety and Depression Scale.MethodFour hundred and four MS patients from two German neurological hospitals were examined for their vaccination attitudes, in detail, the general willingness to vaccinate and the current vaccination status of mumps, measles and rubella (MMR) as well as tetanus and influenza. We also looked at the current level of disability in relation to the current vaccination status, as well as possible associated personality and psychopathological variables.ResultsPatients with a complete MMR vaccination status were significantly younger and those with a complete influenza vaccination status were significantly older than those with related incomplete vaccination status. Tetanus vaccination status completeness did not differ depending on age and did not show substantial association with personality scores. However, influenza vaccination completeness was associated with differences in personality and psychopathological variables; extraversion, openness, novelty seeking, harm avoidance and anxiety. A reported general vaccination willingness was significantly correlated with the current completeness of tetanus and influenza vaccinations. Novelty seeking, persistence, extraversion, agreeableness, conscientiousness and neuroticism were found associated with an increased vaccination willingness. Anxiety and depression were not related to general vaccination willingness.ConclusionsNo specific personality trait could be defined on its own in relation to general vaccination willingness or complete vaccination status. Younger patients should be made more aware of influenza vaccination. Reasons for rather low vaccination rates need to be further investigated.  相似文献   
2.
BackgroundOne in two people with multiple sclerosis (PwMS) will fall in a three-month period. Predicting which patients will fall remains a challenge for clinicians. Standardized functional assessments provide insight into balance deficits and fall risk but their use has been limited to supervised visits.Research questionThe study aim was to characterize unsupervised 30-second chair stand test (30CST) performance using accelerometer-derived metrics and assess its ability to classify fall status in PwMS compared to supervised 30CST.MethodsThirty-seven PwMS (21 fallers) performed instrumented supervised and unsupervised 30CSTs with a single wearable sensor on the thigh. In unsupervised conditions, participants performed bi-hourly 30CSTs and rated their balance confidence and fatigue over 48-hours. ROC analysis was used to classify fall status for 30CST performance.ResultsNon-fallers (p = 0.02) but not fallers (p = 0.23) differed in their average unsupervised 30CST performance (repetitions) compared to their supervised performance. The unsupervised maximum number of 30CST repetitions performed optimized ROC classification AUC (0.79), accuracy (78.4%) and specificity (90.0%) for fall status with an optimal cutoff of 17 repetitions.SignificanceBrief durations of instrumented unsupervised monitoring as an adjunct to routine clinical assessments could improve the ability for predicting fall risk and fluctuations in functional mobility in PwMS.  相似文献   
3.
4.
5.
《Vaccine》2022,40(30):4038-4045
PurposeAs protection from COVID-19 following two doses of the BNT162b2 vaccine showed a time dependent waning, a third (booster) dose was administrated. This study aims to compare the antibody response following the third dose versus the second and to evaluate post-booster seroconversion.MethodsA prospective observational study conducted in Maccabi Healthcare Services. Serial SARS-CoV-2 Spike IgG tests, 1,2,3 and 6 months following the second vaccine dose and one month following the third were obtained. Neutralizing antibody levels were measured in a subset of participants. Per individual SARS-CoV-2 Spike IgG titer ratios were calculated one month after the booster administration compared to titers one month following the second dose and prior to booster.ResultsAmong 110 participants, 56 (51%) were women. Mean age was 61.7 ± 1.9 years and 66 (60%) were immunocompromised. One month after third dose, IgG titers were induced 7.83 (95 %CI 5.25–11.67) folds and 2.40 (95 %CI 1.90–3.03) folds compared to one month after the second, in the immunocompromised and immunocompetent groups, respectively. Of the 17 immunocompromised participants who were seronegative after the second dose, 4 (24%) became seropositive following the third. Comparing the titers prior to the third dose, an increase of 50.7 (95 %CI 32.5–79.1) fold in the immunocompromised group and 25.7 (95 %CI 19.1–34.7) fold in and immunocompetent group, was observed.ConclusionA third BNT162b2 vaccine elicited robust humoral response, superior to the response observed following the second, among immunocompetent and immunocompromised individuals.  相似文献   
6.
We review the spectrum of cutaneous disorders associated with inflammatory and neoplastic plasmacytic pathology. Because plasma cells are derived from B‐lymphocytes our overview includes discussion of certain lymphoplasmacytic proliferations. It is structured along histopathological lines, addressing conditions characterized by (a) cutaneous plasma cell infiltrates, (b) deposits of plasma cell products or their derivatives in the skin and (c) miscellaneous, poorly understood cutaneous complications of plasmacytic disorders. Lesions arising primarily in the skin and those due to cutaneous involvement by multisystem disorders are addressed. The range includes a spectrum of tumefactive and circulatory manifestations. We highlight key clinical and pathological features of the different conditions and outline recent advances in our understanding of these entities. By emphasizing the dermatopathological characteristics of this spectrum of disorders we hope to hone the diagnostic accuracy of practitioners in the field.  相似文献   
7.
Introduction: Dysregulation of histone deacetylase (HDAC) activity is an epigenetic hallmark of multiple myeloma (MM), leading to aberrant gene expression and cellular signaling in myeloma cell growth, survival and resistance to therapy. Hyper-methylation at diagnosis is a frequent observation, which eventually may convert to hypo-methylation during advanced phases.

Areas covered: A literature search on ‘HDAC inhibitors’ and ‘multiple myeloma’ was carried out using PubMed and Google Scholar in the preparation of this overview on clinical efficacy and safety data.

Expert opinion: First-generation non-selective HDAC inhibitors have demonstrated minimal single-agent activity in refractory MM. Subsequently, combination therapy has proven an improvement in progression-free survival (PFS) but not response rates. The main concerns are associated with toxicities. Ongoing studies on new and more selective agents, i.e. Romidepsin or Ricolinostat, are promising in terms of better efficacy and less toxicity.  相似文献   

8.
目的探究肿瘤坏死因子-α(Tumornecrosis factor-α,TNF-α)-308基因对导管相关性脓毒症(Catheter related sepsis,CRS)患者病情的影响,旨在为临床治疗CRS提供科学依据。方法选取2017年7月-2018年10月于浙江大学医学院附属杭州市第一人民医院接受治疗的86例CRS患者为研究对象,按照是否并发多器官功能障碍综合征将患者分为试验组和对照组,对照组共48例,未并发多器官功能障碍综合征,试验组共38例,并发多器官功能障碍综合征,分析两组患者TNF-α-308基因多态性差异,使用多因素Logistic回归分析CRS患者并发多器官功能障碍综合征的危险因素。结果试验组GA基因型频率34.21%、AA基因型频率50.00%、高G等位基因频率18.42%均高于对照组,GG基因型频率52.63%、A等位基因频率28.95%均低于对照组,差异均具有统计学意义(P<0.05);多因素Logistic回归分析结果显示,低GG基因型频率、低G等位基因频率、高GA基因型频率、高AA基因型频率、高A等位基因频率是CRS患者并发多器官功能障碍综合征的危险因素(P<0.05)。结论TNF-α-308基因与CRS患者病情密切相关,GG基因型频率和G等位基因频率降低,GA基因型频率、AA基因型频率、A等位基因频率升高会加重患者的病情,增加多器官功能障碍综合征的发生风险,临床上应该加以重视。  相似文献   
9.
目的:分析超声内镜引导下经支气管针吸活检(endobronchial ultrasound-guided transbronchial needle aspiration,EBUS-TBNA)术中肿大纵隔淋巴结的超声图像特点,探讨EBUS-TBNA超声内镜对纵隔淋巴结良恶性的鉴别诊断价值,以期提高EBUS-TBNA对纵隔淋巴结恶性病变的活检率。方法:回顾性分析2014年10月至2018年11月行EBUS-TBNA患者的超声内镜图像。我们使用以下EBUS超声内镜特征来预测淋巴结的良恶:回声,长轴长度,短轴长度,纵横比,形态,边界,淋巴门有无,淋巴结内血流信号分级。将超声检查结果与最终病理结果或临床随访结果进行比较。采用SPSS 20.0软件进行统计学分析,采用logistic回归分析评价肿大淋巴结EBUS-TBNA超声内镜下的特征与良恶性的相关性,以 P<0.05 为标准判定差异有统计学意义。结果:对130例纵隔淋巴结肿大患者的227个淋巴结进行回顾性分析,67.4%的肿大淋巴结被证实为恶性转移。Logistic回归分析显示回声、长轴及短轴的长度、正常淋巴门结构的消失是诊断恶性淋巴结的独立预测因素。结论:纵隔恶性淋巴结具有一定的超声特征,可以通过这些超声特征提高EBUS-TBNA对纵隔恶性淋巴结的检出率。  相似文献   
10.
IntroductionCognitive deficits and neuropsychiatric symptoms occur in parkinsonian and cerebellar subtypes of Multiple System Atrophy (MSA-P and MSA-C). These symptoms have been investigated mainly in cross-sectional studies. The present 1-year follow-up study aimed at evaluating the evolution of cognitive and neuropsychiatric profile in patients with MSA-C and MSA-P.MethodsTwenty-nine patients with MSA-P, 21 with MSA-C and 30 healthy subjects (HCs) underwent a neuropsychological battery and questionnaires assessing depression and apathy (T0). After 1 year (T1), patients with MSA-C and MSA-P underwent the same neuropsychological and neuropsychiatric tools employed at T0.ResultsAt T0, MSA-P and MSA-C groups were more depressed and apathetic and performed worse on tests assessing repetition abilities, executive and attentive functions than HCs. MSA-P and MSA-C groups did not differ on cognitive variables and neuropsychiatric scales. At T1, a significant worsening in spatial planning and psychomotor speed in MSA-C group and a significant worsening in memory, spatial planning, repetition abilities and functional autonomy in MSA-P group were found. The prevalence of apathy increased in both subtypes, whereas the prevalence of depression was reduced in MSA-C and relatively consistent in MSA-P.ConclusionsThe finding revealed a wide-ranging worsening of cognitive functions in MSA-P and a significant decline in processing speed in MSA-C. These results underline the relevance of evaluating cognitive and psychiatric features of MSA over the course of the disease in the daily clinical practice.  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