全文获取类型
收费全文 | 6847篇 |
免费 | 318篇 |
国内免费 | 96篇 |
专业分类
耳鼻咽喉 | 364篇 |
儿科学 | 70篇 |
妇产科学 | 5篇 |
基础医学 | 826篇 |
口腔科学 | 42篇 |
临床医学 | 355篇 |
内科学 | 284篇 |
皮肤病学 | 4篇 |
神经病学 | 3552篇 |
特种医学 | 320篇 |
外科学 | 437篇 |
综合类 | 449篇 |
预防医学 | 117篇 |
眼科学 | 162篇 |
药学 | 178篇 |
中国医学 | 24篇 |
肿瘤学 | 72篇 |
出版年
2023年 | 71篇 |
2022年 | 80篇 |
2021年 | 124篇 |
2020年 | 150篇 |
2019年 | 143篇 |
2018年 | 164篇 |
2017年 | 178篇 |
2016年 | 185篇 |
2015年 | 179篇 |
2014年 | 328篇 |
2013年 | 397篇 |
2012年 | 345篇 |
2011年 | 374篇 |
2010年 | 339篇 |
2009年 | 372篇 |
2008年 | 439篇 |
2007年 | 396篇 |
2006年 | 356篇 |
2005年 | 295篇 |
2004年 | 267篇 |
2003年 | 214篇 |
2002年 | 183篇 |
2001年 | 144篇 |
2000年 | 151篇 |
1999年 | 130篇 |
1998年 | 132篇 |
1997年 | 138篇 |
1996年 | 98篇 |
1995年 | 105篇 |
1994年 | 92篇 |
1993年 | 64篇 |
1992年 | 55篇 |
1991年 | 73篇 |
1990年 | 50篇 |
1989年 | 49篇 |
1988年 | 36篇 |
1987年 | 30篇 |
1986年 | 44篇 |
1985年 | 48篇 |
1984年 | 36篇 |
1983年 | 38篇 |
1982年 | 35篇 |
1981年 | 21篇 |
1980年 | 17篇 |
1979年 | 27篇 |
1978年 | 12篇 |
1977年 | 10篇 |
1976年 | 15篇 |
1973年 | 9篇 |
1972年 | 9篇 |
排序方式: 共有7261条查询结果,搜索用时 31 毫秒
1.
目的 探讨儿童颞骨骨折的临床特点及治疗策略。 方法 回顾性分析2014年7月~2021年7月首都医科大学附属北京儿童医院确诊的477例18岁以下颞骨骨折患儿的临床资料,包括患儿性别、年龄、受伤原因、影像学、面神经及听力学评估、并发症、治疗及预后。 结果 477例颞骨骨折患儿中男358例、女119例,男女比例为3∶1,年龄范围为0~18岁,中位年龄9岁,其中6例为双侧。交通事故是受伤主要原因(57.23%),其次为跌倒(23.69%)。最常见的临床症状为鼓室积血和耳出血,通常3周~1个月消失。纵行骨折253耳(52.38%),横行骨折35耳(7.25%),混合型骨折48耳(9.93%),其他不能进行分型147耳(30.43%),表现为轻微骨折线。听力受损372例(77.02%);面神经损伤28例(5.80%),其中8例为内听道及以上层面损伤;脑脊液耳漏47例(9.73%);鼓膜穿孔15例(3.11%)。合并颅内损伤78例(16.35%),全身多发损伤19例(3.98%)。即发性面瘫10例,1例恢复良好(10.00%);迟发性面瘫18例,15例恢复良好(83.33%)。耳科并发症的处理经手术治疗10例,包括8例鼓室探查+听骨链重建,术后听阈恢复正常。2例面神经减压术,术后House-Brackmann面神经功能分级(HB分级)Ⅴ级恢复至Ⅱ级。 结论 儿童颞骨骨折中,男童常见,最常见的受伤原因为交通事故。鼓室积血、鼓膜穿孔、脑脊液耳漏和传导性耳聋经保守治疗多可治愈,外伤所致听骨链骨折或脱位经手术治疗预后良好,外伤所致内听道区域骨折可引起极重度感音神经性耳聋和完全性面瘫,预后较差。 相似文献
2.
3.
4.
《Clinical oncology (Royal College of Radiologists (Great Britain))》2022,34(12):e482-e492
AimsTo use pre-treatment magnetic resonance imaging-based radiomics data with clinical data to predict radiation-induced temporal lobe injury (RTLI) in nasopharyngeal carcinoma (NPC) patients with stage T4/N0–3/M0 within 5 years after radiotherapy.Materials and methodsThis study retrospectively examined 98 patients (198 temporal lobes) with stage T4/N0–3/M0 NPC. Participants were enrolled into a training cohort or a validation cohort in a ratio of 7:3. Radiomics features were extracted from pre-treatment magnetic resonance imaging that were T1-and T2-weighted. Spearman rank correlation, the t-test and the least absolute shrinkage and selection operator (LASSO) algorithm were used to select significant radiomics features; machine-learning models were used to generate radiomics signatures (Rad-Scores). Rad-Scores and clinical factors were integrated into a nomogram for prediction of RTLI. Nomogram discrimination was evaluated using receiver operating characteristic analysis and clinical benefits were evaluated using decision curve analysis.ResultsParticipants were enrolled into a training cohort (n = 139) or a validation cohort (n = 59). In total, 3568 radiomics features were initially extracted from T1-and T2-weighted images. Age, Dmax, D1cc and 16 stable radiomics features (six from T1-weighted and 10 from T2-weighted images) were identified as independent predictive factors. A greater Rad-Score was associated with a greater risk of RTLI. The nomogram showed good discrimination, with a C-index of 0.85 (95% confidence interval 0.79–0.92) in the training cohort and 0.82 (95% confidence interval 0.71–0.92) in the validation cohort.ConclusionWe developed models for the prediction of RTLI in patients with stage T4/N0–3/M0 NPC using pre-treatment radiomics data and clinical data. Nomograms from these pre-treatment data improved the prediction of RTLI. These results may allow the selection of patients for earlier clinical interventions. 相似文献
5.
约1/4的难治性颞叶癫痫患者的发作无法通过常规前颞叶切除术得到有效控制,这可能是因为疾病存在多种复杂的亚型,且部分亚型涉及颞叶外的脑区病变。基于多模态脑影像特征,使用隐含狄利克雷分布模型可以估计潜在疾病因子及各因子在患者大脑内的表达程度,有助于个体精准分型。该研究通过PET/MR同步一体扫描仪采集了86名难治性颞叶癫痫患者的T1加权影像和FDG PET影像,并采集了39名健康志愿者的T1加权影像和36名健康志愿者的FDG PET影像作为对照。该研究提取与癫痫病理相关的灰质体积和葡萄糖摄取值,使用隐含狄利克雷分布进行分型,将疾病因子的数量分别设为3、4、5,进行多次实验,并对四因子模型中的各疾病因子与临床指标之间的关系进行统计分析。研究发现,选取不同数量的疾病因子进行分型时得到的结果具有一定的相似性。在四因子模型中存在与病灶偏侧性、癫痫发作年限和认知能力显著相关(P<0.05)的疾病因子。该研究对颞叶癫痫分型具有一定的参考价值。 相似文献
6.
7.
《Biomedical and environmental sciences : BES》2022,35(9):773-781
ObjectiveImprovement in the quality of life is reflected in the narrowing of the gap between health-adjusted life expectancy (HALE) and life expectancy (LE). The effect of megacity expansion on narrowing the gap is rarely reported. This study aimed to disclose this potential relationship.MethodsAnnual life tables were constructed from identified death records and population counts from multiple administrative sources in Guangzhou, China, from 2010 to 2020. Joinpoint regression was used to evaluate the temporal trend. Generalized principal component analysis and multilevel models were applied to examine the county-level association between the gap and social determinants.ResultsAlthough LE and HALE in megacities are increasing steadily, their gap is widening. Socio-economic and health services are guaranteed to narrow this gap. Increasing personal wealth, a growing number of newborns and healthy immigrants, high urbanization, and healthy aging have helped in narrowing this gap.ConclusionIn megacities, parallel LE and HALE growth should be highly considered to narrow their gap. Multiple social determinants need to be integrated as a whole to formulate public health plans. 相似文献
8.
9.
Beata Lindholm Frida Eek
rjan Skogar Eva E. Hansson 《Acta neurologica Scandinavica》2019,139(6):512-518
A growing body of research highlights the importance of cognition for prediction of falls in Parkinson's disease (PD). However, a previously proposed prediction model for future near falls and falls in PD, which includes history of near falls, tandem gait, and retropulsion, was developed without considering cognitive impairment. Therefore, by using a sample of 64 individuals with relatively mild PD and not excluding those with impaired cognition we aimed to externally validate the previously proposed model as well as to explore the value of additional predictors that also consider cognitive impairment. Since this validation study failed to support the proposed model in a PD sample including individuals with impaired global cognition, extended analyses generated a new model including dyskinesia (item 32 of Unified PD Rating Scale) and frontal lobe impairment (Frontal Assessment Battery—FAB) as significant independent predictors for future near falls and falls in PD. The discriminant ability of this new model was acceptable (AUC, 0. 80; 95% CI 0.68‐0.91). Replacing the continuous FAB scores by a dichotomized version of FAB with a cut‐off score ≤14 yielded slightly lower but still acceptable discriminant ability (AUC, 0. 79; 95% CI 0.68‐0.91). Further studies are needed to test our new model and the proposed cut‐off score of FAB in additional samples. Taken together, our observations suggest potentially important additions to the evidence base for clinical fall prediction in PD with concomitant cognitive impairment. 相似文献
10.
Jungchan Park Gyu‐Seong Choi Mi Sook Gwak Justin Sangwook Ko Bobae Han Sangbin Han Jae Won Joh Suk‐Koo Lee Jongman Kim Gaab Soo Kim 《Transplant international》2019,32(2):141-152
Despite technical difficulties, right lobe liver grafting is preferred in living donor liver transplantation because of the graft size. Re‐exploration after living donor right lobe liver transplantation (LRLT) has never been separately analyzed. We aimed to analyze the incidence, causes, outcomes, and risk factors of re‐exploration after LRLT. We reviewed medical records of 1016 LRLT recipients from October 2003 to July 2017 and identified recipients who underwent re‐exploration within hospital stay. Separate analyses were also performed according to cause of re‐exploration. The overall incidence of re‐exploration was 17.0% (173/1016). The most common cause of re‐exploration was bleeding (50%). Overall re‐exploration was associated with clinical outcome, but different results were shown on analyses according to cause of re‐exploration. Risk factors of re‐exploration were underlying hepatocellular carcinoma and operative duration [Odds ratio (OR), 1.49; 95% confidence interval (CI), 1.05–2.12; P = 0.03, and OR, 1.002; 95% CI, 1.001–1.004; P = 0.0023, respectively]. Re‐exploration after LRLT is relatively common, and is strongly associated with mortality and graft failure. 相似文献