全文获取类型
收费全文 | 19703篇 |
免费 | 1570篇 |
国内免费 | 214篇 |
专业分类
耳鼻咽喉 | 91篇 |
儿科学 | 110篇 |
妇产科学 | 104篇 |
基础医学 | 835篇 |
口腔科学 | 253篇 |
临床医学 | 3465篇 |
内科学 | 3196篇 |
皮肤病学 | 112篇 |
神经病学 | 925篇 |
特种医学 | 316篇 |
外科学 | 1660篇 |
综合类 | 3409篇 |
一般理论 | 2篇 |
预防医学 | 3554篇 |
眼科学 | 102篇 |
药学 | 1972篇 |
27篇 | |
中国医学 | 504篇 |
肿瘤学 | 850篇 |
出版年
2024年 | 74篇 |
2023年 | 376篇 |
2022年 | 599篇 |
2021年 | 912篇 |
2020年 | 815篇 |
2019年 | 932篇 |
2018年 | 961篇 |
2017年 | 877篇 |
2016年 | 892篇 |
2015年 | 839篇 |
2014年 | 1877篇 |
2013年 | 1799篇 |
2012年 | 1524篇 |
2011年 | 1480篇 |
2010年 | 1110篇 |
2009年 | 903篇 |
2008年 | 874篇 |
2007年 | 756篇 |
2006年 | 627篇 |
2005年 | 561篇 |
2004年 | 420篇 |
2003年 | 338篇 |
2002年 | 312篇 |
2001年 | 258篇 |
2000年 | 206篇 |
1999年 | 157篇 |
1998年 | 114篇 |
1997年 | 99篇 |
1996年 | 73篇 |
1995年 | 59篇 |
1994年 | 66篇 |
1993年 | 61篇 |
1992年 | 35篇 |
1991年 | 39篇 |
1990年 | 35篇 |
1989年 | 17篇 |
1988年 | 16篇 |
1987年 | 18篇 |
1986年 | 10篇 |
1985年 | 53篇 |
1984年 | 67篇 |
1983年 | 39篇 |
1982年 | 55篇 |
1981年 | 53篇 |
1980年 | 29篇 |
1979年 | 28篇 |
1978年 | 16篇 |
1977年 | 17篇 |
1976年 | 9篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
71.
摘 要: 目的:探究中老年人颈动脉斑块与血清25羟维生素D (25-OH-D) 的相关性。 方法:选取2019年1月—2020
年 12 月自愿参与该研究的上海市浦东新区北蔡社区常住居民 412 人为研究对象,测定及记录其一般临床资料及血清
25-OH-D 等实验室检测结果。依据血管 B 超结果将研究对象分为有斑块组 268 人和无斑块组 144 人,比较两组人群血清
25-OH-D水平差异,用Pearson相关性分析各变量的关系,采用logistic回归分析颈动脉斑块形成的危险因素。结果:有斑块
组血清 25-OH-D 为 (45.18±18.71) nmol/L,无斑块组为 (56.12±19.54) nmol/L,两组差异有统计学意义 (χ2=5.573,P<
0.05)。相关性分析显示颈动脉斑块与收缩压、HbA1c、年龄呈正相关 (r值分别为0.388、0.119和0.128,P值均<0.05);与
血清 25-OH-D 呈负相关 (r=-0.365,P<0.01)。血清 25-OH-D 是颈动脉斑块形成的独立相关因素 (OR=0.973,95%CI:
0.960,0.985,P<0.05)。结论:低水平血清25-OH-D是颈动脉斑块形成的独立危险因素。 相似文献
72.
《Health & place》2021
Within the United States South, the socio-religious norms that shape life for many residents may have public health implications. Drawing from 12 key informant interviews, this study explores the role of religious institutions in HIV care and prevention access among transgender people of color in Southern cities. Findings suggest that while religious anti-transgender stigma is pervasive, the regional importance of faith-based beliefs and institutions necessitates targeted faith-based initiatives for the population. Broadly, findings suggest regional environments may demand interventions that negotiate historically marginalizing relationships between at-risk groups and dominant cultural institutions. 相似文献
73.
目的分析老年慢性病患者肺部感染与白细胞分化抗原14(CD14)和人类白细胞抗原(HLA)基因多态性的关系。方法选取2017年10月-2019年10月菏泽市单县中心医院老年慢性疾病患者615例,以其中合并肺部感染者97例(15.77%)为研究组,另在未合并肺部感染者中随机抽取92例为对照组,采集两组临床资料,检测并比较两组CD14-159 C/T、CD14-260 C/T和HLA-A、HLA-B和HLA-DRB1基因分布。结果两组患者性别、年龄、体质量指数(BMI)及基础疾病等临床资料比较差异无统计学意义,研究组合并慢性疾病种类较对照组多(P<0.05);两组CD14-159 C/T基因型分布差异显著(P<0.05),研究组CD14-159 C等位基因频率显著低于对照组,T等位基因频率显著高于对照组(P<0.05),两组CD14-260 C/T基因型及等位基因频率比较差异无统计学意义;研究组HLA-A*0101等位基因频率高于对照组,HLA-B*5201和HLA-DRB1*1502等位基因频率低于对照组,差异有统计学意义(P<0.05)。结论合并慢性疾病种类较多的老年慢性疾病患者容易发生肺部感染,感染可能与CD14和HLA基因多态性有关,CD14-159 TT和HLA-A*0101可能为易感基因。 相似文献
74.
Ushma D. Upadhyay Phoebe Y. Danza Torsten B. Neilands Jessica D. Gipson Claire D. Brindis Michelle J. Hindin Diana Greene Foster Shari L. Dworkin 《The Journal of adolescent health》2021,68(1):86-94
PurposeWe developed and validated a measure that assesses the latent construct of sexual and reproductive empowerment among adolescents and young adults. A specific measure for this group is critical because of their unique life stage and circumstances, which often includes frequent changes in sexual partners and involvement from parents in decision-making.MethodsAfter formative qualitative research, a review of the literature, and cognitive interviews, we developed 95 items representing nine dimensions of sexual and reproductive empowerment. Items were then fielded among a national sample of young people aged 15–24 years, and those who identified as sexually active completed a 3-month follow-up survey. We conducted psychometric analysis and scale validation.ResultsExploratory factor analysis on responses from 1,117 participants resulted in the Sexual and Reproductive Empowerment Scale for Adolescents and Young Adults, containing 23 items captured by seven subscales: comfort talking with partner; choice of partners, marriage, and children; parental support; sexual safety; self-love; sense of future; and sexual pleasure. Validation using logistic regression demonstrated that the subscales were consistently associated with sexual and reproductive health information and access to sexual and reproductive health services measured at baseline and moderately associated with the use of desired contraceptive methods at 3-month follow-up.ConclusionsThe Sexual and Reproductive Empowerment Scale for Adolescents and Young Adults is a new measure that assesses young people’s empowerment regarding sexual and reproductive health. It can be used by researchers, public health practitioners, and clinicians to measure sexual and reproductive empowerment among young people. 相似文献
75.
76.
《Journal of the American Medical Directors Association》2022,23(4):671-677.e4
ObjectivesWe examined whether the comorbidity burden of patients with hip fracture was associated with quality of in-hospital care reflected by fulfillment of process performance measures.DesignPopulation-based cohort study using prospectively collected data from the Danish Multidisciplinary Hip Fracture Registry (DMHFR).Setting and ParticipantsPatients aged 65 years or older with an incident hip fracture from 2014 to 2018 registered in the DMHFR (n = 31,443).MethodsComorbidity was measured using the Charlson Comorbidity Index based on hospital diagnoses. Quality of in-hospital care was defined as fulfillment of eligible process performance measures, including preoperative optimization, early surgery, early mobilization, pain assessment, basic mobility, nutritional risk, need for anti-osteoporotic medication, fall prevention, and a post-discharge rehabilitation program, reflecting guideline-recommended in-hospital care. The outcomes were (1) an all-or-none composite measure defined as fulfillment of all relevant process performance measures, and (2) fulfillment of the individual process performance measures. Using binary regression, we calculated relative risk (RR) for the association between comorbidity level and outcomes.ResultsThe overall proportion of patients with hip fracture who fulfilled the all-or-none measure was 31%. Among patients with no comorbidity, 34% fulfilled the all-or-none measure versus 29% among patients with high comorbidity (Charlson ≥ 3). This corresponds to a 15% lower chance (RR = 0.85, 95% confidence interval 0.81–0.89). Increasing comorbidity was also associated with lower fulfillment of the individual process performance measures. The largest difference was seen for preoperative optimization, early surgery, and early mobilization, where patients with high comorbidity had 6% to 11% lower chance of fulfillment of these process performance measures compared with patients without comorbidity.Conclusion and ImplicationsIncreasing level of comorbidity was associated with lower quality of in-hospital care among patients with hip fracture. Our results highlight the need for tailored clinical initiatives to ensure that comorbid patients also benefit from the positive progress in hip fracture care in recent years. 相似文献
77.
目的 :探讨老年人的膳食及营养状况。方法 :选择 97名 60~ 69岁男性为调查对象 ;膳食调查采用 4天称量法 ;尿负荷试验 ,试验者于清晨空腹时口服维生素 B1、B2 各 5mg及维生素 C 50 0 mg,收集 4 h尿 ,用 2 ,4 -二硝基苯肼比色法测定尿中维生素 C含量 ;用荧光光度法测定尿中维生素 B1、B2 含量。结果 :维生素 A和钙的摄入量分别占供给量 2 1.5%和 52 .7% ,热能和其他营养素摄入量均超过或达到我国推荐的营养素供给量标准。结论 :老年人从膳食中摄入的热能和大多数营养素均达到了供给量标准 相似文献
78.
79.
Zeyad T. Sahli Joseph K. Canner Martha A. Zeiger Aarti Mathur 《American journal of surgery》2021,221(2):478-484
BackgroundThe aim of this study was to evaluate the association between age and disease specific mortality (DSM) among adults diagnosed with medullary thyroid cancer (MTC).MethodSurveillance, Epidemiology, and End Results (SEER-18) was used to analyze adult MTC patients stratified by age (18–64, 65–79, ≥80 years). Associations between patient demographics, tumor size, nodal status, metastatic disease, and extent of surgery on DSM was assessed with multivariable Cox regression.ResultsAmong 1457 patients with MTC, 1008 (69.2%) were younger adults, 371 (25.5%) older adults, and 78 (5.4%) were super-elderly. A significantly higher proportion of older adults and super-elderly had less than the recommended operation for MTC. On multivariable analysis, older adults and super-elderly were 2.9 and 6.7 times more likely to have an increased DSM (HR:2.91, 95% CI: 1.83–4.63; p < 0.001 and HR: 6.70, 95%CI: 3.69–12.20; p < 0.001). Extent of surgery or lymphadenectomy did not affect DSM.ConclusionsIncreased age is an independent predictor of DSM in patients with MTC. 相似文献
80.