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   46949篇
  免费   5059篇
  国内免费   1226篇
耳鼻咽喉   664篇
儿科学   700篇
妇产科学   285篇
基础医学   2914篇
口腔科学   6202篇
临床医学   5118篇
内科学   5851篇
皮肤病学   431篇
神经病学   2278篇
特种医学   674篇
外国民族医学   3篇
外科学   2471篇
综合类   8419篇
现状与发展   6篇
一般理论   2篇
预防医学   4070篇
眼科学   3200篇
药学   4138篇
  49篇
中国医学   4994篇
肿瘤学   765篇
  2024年   219篇
  2023年   1196篇
  2022年   1795篇
  2021年   2525篇
  2020年   2486篇
  2019年   2060篇
  2018年   2163篇
  2017年   2083篇
  2016年   2233篇
  2015年   2002篇
  2014年   3613篇
  2013年   3467篇
  2012年   3206篇
  2011年   3226篇
  2010年   2422篇
  2009年   2018篇
  2008年   1993篇
  2007年   1961篇
  2006年   1669篇
  2005年   1450篇
  2004年   1233篇
  2003年   1162篇
  2002年   815篇
  2001年   796篇
  2000年   612篇
  1999年   584篇
  1998年   440篇
  1997年   421篇
  1996年   362篇
  1995年   344篇
  1994年   309篇
  1993年   228篇
  1992年   236篇
  1991年   185篇
  1990年   153篇
  1989年   162篇
  1988年   122篇
  1987年   120篇
  1986年   113篇
  1985年   163篇
  1984年   143篇
  1983年   110篇
  1982年   131篇
  1981年   95篇
  1980年   105篇
  1979年   48篇
  1978年   60篇
  1977年   34篇
  1976年   32篇
  1973年   20篇
排序方式: 共有10000条查询结果,搜索用时 31 毫秒
1.
《台湾医志》2022,121(12):2490-2500
Background/PurposeOrthokeratology (Ortho-K), atropine eye drops and combined atropine with Ortho-K are proven to be effective ways to prevent myopic progression in many studies, but there is scarce evidence regarding the comparative efficacy of different dosages of atropine,Ortho-K, and combined atropine with Ortho-K for childhood myopia.MethodsWe performed a network meta-analysis (NMA) to assess the relative efficacy of the aforementioned interventions for myopic progression; moreover, we calculated the surface under cumulative ranking area (SUCRA) to determine the relative ranking of treatments.ResultsWe identified 19 randomized controlled trials (3435 patients). NMA revealed that 0.01%–1% atropine, Ortho-K, and 0.01% atropine combined with Ortho-K inhibited axial elongation (AL) over one year. For refractive change, SUCRA analysis revealed that the hierarchy was high-dose (0.5%–1%), moderate-dose (0.1%–0.25%), and low-dose (0.01%–0.05%) atropine. Regarding AL, SUCRA analysis revealed the following hierarchy: Ortho-K combined with 0.01% atropine, high-dose atropine, moderate-dose atropine, Ortho-K, and low-dose atropine.ConclusionIn conclusion, we found that atropine (0.01%–1%), Ortho-K, and 0.01% atropine combined with Ortho-K could significantly slow down myopia progression. The atropine efficacy followed a dose-related pattern; moreover, Ortho-K and low-dose atropine showed similar efficacy. There was a synergistic effect of using 0.01% atropine combined with Ortho-K, and it showed comparable efficacy to that of high-dose atropine.  相似文献   
2.
Discrimination towards individuals with disabilities is problematic within nursing. There have been calls to increase diversity in nursing and this includes embracing nurses with disabilities. Increasing diversity in nursing requires increasing diversity among nursing students; in this way, nurse educators are gatekeepers to the profession. Clinical education is a crucial element of nursing education, yet there have been very few studies related to the clinical education of nursing students with disabilities. There have been no studies of attitudes of acute care nurse preceptors toward students with disabilities in the United States. This gap is important as the majority of clinical experiences occur in the acute care environment. Utilizing a focused ethnography, semi-structured interviews were conducted with 20 acute care nurses with at least two years’ experience precepting students. While positive feelings about nursing students with disabilities were shared, thoughts and behavioral intentions remained negative. Six themes emerged: safety, barriers, otherness, communicating to meet needs, disclosure, and student versus colleague. Attitudinal barriers are the primary barriers faced by individuals with disabilities in becoming and practicing as nurses. Nurses in practice and education must embrace more inclusive attitudes towards individuals with disabilities.  相似文献   
3.
《Pancreatology》2022,22(8):1175-1180
BackgroundHepatic steatosis has been described as a common finding in adults following total pancreatectomy with islet autotransplantation (TPIAT) but it is unknown if this occurs in children and adolescents.ObjectivesTo define the frequency of post-TPIAT hepatic steatosis in a sample of children and adolescents and to identify clinical predictors of incident steatosis post-TPIAT.MethodsIn this prospective study, consecutive participants at least 1-month post-TPIAT underwent a liver MRI with proton density fat fraction (PDFF) and blood draw at our pediatric academic medical center between April 2021 and January 2022. Comparison clinical pre-TPIAT liver MRI or ultrasound and insulin use and graft function data were extracted from the medical record. T-tests were used for the comparison of means across continuous variables between participants with and without post-TPIAT steatosis.ResultsA total of 20 participants (mean: 13 ± 4 years; 12 female) were evaluated. Mean liver PDFF at research MRI was 7.4 ± 6.2% (range: 2–25%). Seven participants (35%) had categorical hepatic steatosis (PDFF>5%) post-TPIAT, five of whom had pre-TPIAT steatosis, reflecting a 13% (2/15; 95% CI: 2–40%) incidence of post-TPIAT steatosis. Participant characteristics were not significantly different between subgroups with and without post-TPIAT steatosis. Mean PDFF at research MRI was not different between graft function subgroups (7.5% optimal/good vs. 7.3% marginal/failure; p = .96).ConclusionOur study shows a moderate prevalence but low incidence of hepatic steatosis in a small sample of children and adolescents post-TPIAT. This study raises questions about a causal relationship between TPIAT and hepatic steatosis.  相似文献   
4.
BackgroundDespite indications for the removal of temporary inferior vena cava (IVC) filters, many filters are unintentionally left in place, predisposing patients to adverse outcomes.ObjectiveThis quality improvement study set out to determine the impact of an IVC filter retrieval protocol on filter retrieval rates and patients lost to follow-up for patients who had undergone placement of a temporary IVC filter.MethodsFollowing a quasi-experimental design, data of all consecutive patients who underwent insertion of a temporary IVC filter for a period of 24-month preprotocol and 12-month postprotocol were compared.ResultsFilter retrieval rates of eligible filters increased from 64.2% to 100%; patients lost to follow-up decreased from 35.9% to 0% (p < .01, both outcomes).ConclusionAdoption of a comprehensive IVC filter protocol by the service that implants these devices can improve filter retrieval rates and decrease patients being lost to follow-up.  相似文献   
5.
??Objective    To discuss the influence of basic periodontal therapy on the level of IL-8?? IL-10 in serum and gingival crevicular fluid in patients who have chronic periodontitis complicated by coronary heart disease. Methods     A total of 65 cases of patients with chronic periodontitis complicated by coronary heart disease were selected and divided into two groups randomly??Group A of 35 patients who received the basic periodontal therapy and cardiac medical treatment??Group B of 30 patients who received cardiological treatment only. Then??select 25 patient who had developed chronic severe periodontitis with non-systematic disease to establish group C and give them the basic periodontal therapy only. Observe the changes of the IL-8??IL-10 levels in serum and gingival crevicular fluid and the periodontal infection indexes??BI??PD??. Results    The results showed that after three months of basic periodontal therapy the periodontal clinical indices of both group A and group C became better and the IL-8 level obviously reduced??while the IL-10 level obviously increased. There was no obvious difference between group A and group B in each examination index before the therapy. After three months??we found that the periodontal infection index??SBI PD??of group A was obviously better than group B. Compared to group B??the IL-8 level of group A obviously reduced??and the IL-10 level obviously increased. The difference was statistically significant??P < 0.05??. Conclusion    The basic periodontal therapy can effectively improve periodontal conditions of the patients with chronic periodontal diseases??and reduce the risk of breaking the normal cardiovascular function.  相似文献   
6.
观察并评估角膜电刺激对糖尿病大鼠前部缺血性视神经病变(AION)模型的影响。方法:实验 研究。健康雄性Sparague-Dawley大鼠40只,随机分组后抽出8只作为正常大鼠组。余下32只先予 以链脲佐菌素腹腔注射建立糖尿病大鼠模型,将造模成功的大鼠随机抽出8只作为糖尿病组,余下 24只糖尿病大鼠采用孟加拉玫瑰红联合532 nm激光方法建立AION大鼠模型。将24只造模成功的 AION大鼠随机分成3组,每组8只,分别为AION模型组,不予任何处理;电刺激组,予以角膜电刺 激(刺激参数为:电流1 mA,频率20 Hz,波宽1 ms/phase,刺激时间1 h,隔日1次,刺激2周);假电 刺激组,电极安放位置与电刺激组相同,仅不接通电源。2周后5组大鼠进行眼底照相、光学相干断 层扫描和视觉诱发电位,然后处死,行视网膜及视神经冰冻切片,苏木精伊红染色观察。数据采用 单因素方差分析和LSD-t检验进行分析。结果:正常大鼠组视盘上半部视网膜厚度为(211±13)μm, 糖尿病大鼠组为(206±16)μm,AION模型组为(240±54)μm,假电刺激组为(216±11)μm,电刺 激组为(198±4)μm,5组视盘上半部视网膜厚度差异有统计学意义(F=2.854,P=0.038)。其中AION 模型组视盘上半部视网膜厚度高于正常组、糖尿病组、电刺激组,差异均有统计学意义(P<0.05); 正常组与糖尿病组差异无统计学意义,AION模型组与假电刺激组未见明显差异。视觉诱发电位示 AION模型组N1潜伏期较电刺激组延长,差异有统计学意义(t=4.1,P<0.001);AION模型组P1潜伏 期较正常组、糖尿病组、假电刺激组、电刺激组延长,差异均有统计学意义(t=4.1、2.5、2.6、3.2, P<0.05);电刺激组N1-P1波幅大于假电刺激组,差异有统计学意义(t=4.0,P<0.001)。结论:角膜电 刺激能促进糖尿病大鼠前部缺血性视神经病变模型肿胀的视盘变薄,加速视盘水肿的消退,同时在 一定程度上改善视功能。  相似文献   
7.
多生牙也称额外牙,发生率占恒牙列人群的1%~3%,发生于牙弓腭侧者约占85.2%、牙弓内占13.8%、唇颊侧区占1%[1],发生于上颌前牙区者约占98.24%[2]。本病例2颗多生牙萌出于患者右上颌第二、第三磨牙颊侧。现报告如下。1临床资料患者男,40岁。因"右上颌后牙食物嵌塞"于2013-09-25就诊于南昌大学附属口腔医院。检查:全身一般状况良好,口腔内牙齿咬合关系良  相似文献   
8.
Research supports that people of color in the U.S. have poorer outcomes after burn injury compared to White individuals. The current study sought to explore burn health disparities by testing the relationship between racial and ethnic minority status, a proxy for systemic discrimination due to race and ethnicity, with two key constructs linked to functional outcomes, satisfaction with appearance and social community integration. Participants included 1318 burn survivors from the Burn Model System National Database (mean age = 40.2, SD = 12.7). Participants completed measures of satisfaction with appearance and social community integration at baseline, 6-, 12-, and 24-months after burn injury. Linear regressions revealed that racial and ethnic minority status significantly related to lower satisfaction with appearance and social community integration compared to White individuals at all time points. In addition, satisfaction with appearance continued to significantly relate to greater social community integration even while accounting for race and ethnicity, age, sex, burn size, and physical disability at 6-, 12-, and 24-month time points. Overall, the study supports that racial and ethnic minority burn survivors report greater dissatisfaction with their appearance and lower social community reintegration after burn injury.  相似文献   
9.

Background

Resistin is an immunometabolic mediator that is elevated in several inflammatory disorders. A ligand for Toll-like receptor 4, resistin modulates the recruitment and activation of myeloid cells, notably neutrophils. Neutrophils are major drivers of cystic fibrosis (CF) lung disease, in part due to the release of human neutrophil elastase- and myeloperoxidase-rich primary granules, leading to tissue damage. Here we assessed the relationship of resistin to CF lung disease.

Methods

Resistin levels were measured in plasma and sputum from three retrospective CF cohorts spanning a wide range of disease. We also assessed the ability of neutrophils to secrete resistin upon activation in vitro. Finally, we constructed a multivariate model assessing the relationship between resistin levels and lung function.

Results

Plasma resistin levels were only marginally higher in CF than in healthy control subjects. By contrast, sputum resistin levels were very high in CF, reaching 50–100 fold higher levels than in plasma. Among CF patients, higher plasma resistin levels were associated with allergic bronchopulmonary aspergillosis, and higher sputum resistin levels were associated with CF-related diabetes. Mechanistically, in vitro release of neutrophil primary granules was concomitant with resistin secretion. Overall, sputum resistin levels were negatively correlated with CF lung function, independently of other variables (age, sex, and genotype).

Conclusions

Our data establish relationships between resistin levels in the plasma and sputum of CF patients that correlate with disease status, and identify resistin as a novel mechanistic link between neutrophilic inflammation and lung disease in CF.  相似文献   
10.
目的 探讨577 nm激光光凝联合玻璃体内注射康柏西普治疗糖尿病性黄斑水肿的效果。方法 选取2016年1月至2017年3月在我院治疗的糖尿病性黄斑水肿患者81例81眼,根据患者最终选取的治疗方案分为观察组43例43眼和对照组38例38眼,观察组给予577 nm激光光凝联合玻璃体内注射康柏西普治疗,对照组仅给予577 nm激光光凝,观察两组治疗前后最佳矫正视力(best corrected visual acuity,BCVA)和黄斑中心凹厚度(central fovea of macula thickness,CMT),分析观察组BCVA和CMT变化值与初始因素的相关性。结果 随治疗时间延长,观察组和对照组BCVA、CMT相应改善(均为P<0.05);观察组治疗后1个月、3个月和6个月BCVA分别为0.37±0.09、0.44±0.10和0.52±0.13,均明显高于对照组(均为P<0.05);观察组治疗后1个月、3个月和6个月CMT分别为(351.03±41.43)μm、(270.32±40.03)μm和(220.01±32.91)μm,均明显低于对照组(均为P<0.05);BCVA变化值与糖尿病性黄斑水肿病程、治疗前BCVA呈负相关(r=-0.422、-0.410,均为P<0.05);CMT变化值与糖尿病性黄斑水肿病程、治疗前CMT呈负相关(r=-0.430、-0.415,均为P<0.05)。结论 577 nm激光光凝联合玻璃体内注射康柏西普治疗糖尿病性黄斑水肿效果较好,其效果与患者基线BCVA、糖尿病性黄斑水肿病程有一定相关性。  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