全文获取类型
收费全文 | 156234篇 |
免费 | 14169篇 |
国内免费 | 8348篇 |
专业分类
耳鼻咽喉 | 1467篇 |
儿科学 | 2463篇 |
妇产科学 | 3066篇 |
基础医学 | 14831篇 |
口腔科学 | 3274篇 |
临床医学 | 19511篇 |
内科学 | 22544篇 |
皮肤病学 | 2041篇 |
神经病学 | 6838篇 |
特种医学 | 5490篇 |
外国民族医学 | 40篇 |
外科学 | 16224篇 |
综合类 | 27094篇 |
现状与发展 | 28篇 |
一般理论 | 18篇 |
预防医学 | 12618篇 |
眼科学 | 3736篇 |
药学 | 16646篇 |
143篇 | |
中国医学 | 9071篇 |
肿瘤学 | 11608篇 |
出版年
2024年 | 477篇 |
2023年 | 1989篇 |
2022年 | 4808篇 |
2021年 | 6423篇 |
2020年 | 4978篇 |
2019年 | 4095篇 |
2018年 | 4452篇 |
2017年 | 4459篇 |
2016年 | 3832篇 |
2015年 | 6225篇 |
2014年 | 8091篇 |
2013年 | 8762篇 |
2012年 | 12566篇 |
2011年 | 13550篇 |
2010年 | 9929篇 |
2009年 | 8398篇 |
2008年 | 10080篇 |
2007年 | 9896篇 |
2006年 | 9273篇 |
2005年 | 8201篇 |
2004年 | 5995篇 |
2003年 | 5340篇 |
2002年 | 4488篇 |
2001年 | 3834篇 |
2000年 | 3481篇 |
1999年 | 2851篇 |
1998年 | 1356篇 |
1997年 | 1271篇 |
1996年 | 1024篇 |
1995年 | 979篇 |
1994年 | 910篇 |
1993年 | 521篇 |
1992年 | 901篇 |
1991年 | 816篇 |
1990年 | 679篇 |
1989年 | 580篇 |
1988年 | 529篇 |
1987年 | 469篇 |
1986年 | 370篇 |
1985年 | 291篇 |
1984年 | 186篇 |
1983年 | 169篇 |
1982年 | 101篇 |
1981年 | 95篇 |
1979年 | 141篇 |
1978年 | 112篇 |
1977年 | 84篇 |
1974年 | 94篇 |
1973年 | 72篇 |
1972年 | 87篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
41.
42.
43.
Melatonin induces apoptosis of colorectal cancer cells through HDAC4 nuclear import mediated by CaMKII inactivation
下载免费PDF全文
![点击此处可从《Journal of pineal research》网站下载免费的PDF全文](/ch/ext_images/free.gif)
Melatonin induces apoptosis in many different cancer cell lines, including colorectal cancer. However, the precise mechanisms involved remain largely unresolved. In this study, we provide evidence to reveal a new mechanism by which melatonin induces apoptosis of colorectal cancer LoVo cells. Melatonin at pharmacological concentrations significantly suppressed cell proliferation and induced apoptosis in a dose‐dependent manner. The observed apoptosis was accompanied by the melatonin‐induced dephosphorylation and nuclear import of histone deacetylase 4 (HDAC4). Pretreatment with a HDAC4‐specific siRNA effectively attenuated the melatonin‐induced apoptosis, indicating that nuclear localization of HDAC4 is required for melatonin‐induced apoptosis. Moreover, constitutively active Ca2+/calmodulin‐dependent protein kinase II alpha (CaMKIIα) abrogated the melatonin‐induced HDAC4 nuclear import and apoptosis of LoVo cells. Furthermore, melatonin decreased H3 acetylation on bcl‐2 promoter, leading to a reduction of bcl‐2 expression, whereas constitutively active CaMKIIα(T286D) or HDAC4‐specific siRNA abrogated the effect of melatonin. In conclusion, the present study provides evidence that melatonin‐induced apoptosis in colorectal cancer LoVo cells largely depends on the nuclear import of HDAC4 and subsequent H3 deacetylation via the inactivation of CaMKIIα. 相似文献
44.
目的:肌少症对老年肝癌术后恢复及预后的影响。方法:选取2015年1月至2017年12月收治的114例老年肝癌,根据有无合并肌少症,分为肌少症组(n=35)和非肌少症组(n=79)。比较两组患者的术后恢复及生存情况。结果:肌少症组总并发症发生率、住院时间和30 d再入院率均高于对照组,差异均有统计学意义(P<0.05)。肌少症组中位生存时间为25.9个月,1年、2年、3年累积总生存率为74.3%、51.1%、24.5%,而非肌少症组中位生存时间为35.7个月,1年、2年、3年累积总生存率为87.3%、75.6%、49.4%,差异有统计学意义(P=0.004)。单因素分析结果显示,老年肝癌术后预后与Charlson合并症指数(CCI)、肌少症、巴塞罗那分期(BCLC)、甲胎蛋白、肿瘤大小、肿瘤个数、肿瘤分化程度、微血管侵犯(MVI)相关(P<0.05)。Cox多因素分析结果显示,CCI、肌少症、BCLC分期、肿瘤个数、MVI是老年肝癌术后预后的独立危险因素(P<0.05)。结论:肌少症会增加老年肝癌患者术后并发症发生率,延长住院时间,影响术后恢复,同时也会降低总生存率。 相似文献
45.
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
46.
目的探讨专科护士-社区护士-个体-家庭四方联动防跌护理模式在社区跌倒高危老年人中的应用与效果。方法选取深圳市龙岗区的2个社区,随机分为观察组和对照组,从两个社区登记建档的跌倒高风险老年居民中分别随机抽选45名进行干预。观察组采用"专科护士-社区护士-个体-家庭"四方联动推进的综合干预方案。对照组接受社区防跌倒常规护理。于干预前及干预后12个月使用修订版社区老年人跌倒危险评估量表、步态和平衡测试量表对两组老年人进行评测,记录两组1年内跌倒发生例次。结果干预期间跌倒发生情况:观察组1人次,对照组6人次。观察组步态和平衡测试得分提高,跌倒危险评估表得分降低,与对照组比较,差异有统计学意义(均P0.01)。结论四方联动的综合干预方案应用于社区居家老年人,能有效降低老年人跌倒风险,提升其防跌能力,对预防社区老年人跌倒的发生有积极作用。 相似文献
47.
目的:探讨益胃汤加味对改善原发性干燥综合征(primary sj?rgren's syndrome,pSS)气阴两虚、瘀血阻络证患者疲劳症状及免疫学指标的治疗效果。方法:将116例原发性干燥综合征患者按照随机、对照、单盲法分为治疗组与对照组,每组58例。治疗组给予益胃汤加味方,每日1剂,2次/d;对照组给予硫酸羟氯喹200 mg/次,2次/d,两组均连续治疗24周。比较治疗前后两组患者中医证候疗效、中医疲劳症状积分、疲劳症状视觉模拟评分(visual analogue scale,VAS)以及类风湿因子(rheumatoid factor,RF)与血清免疫球蛋白G(immunoglobulin G,IgG)水平。结果:治疗后治疗组患者中医证候疗效优于对照组(Z=3. 712,P0. 05);治疗组中医疲劳积分与疲劳症状视觉模拟评分改善均优于对照组(P0. 05)。治疗6个月后,治疗组IgG水平较本组治疗前明显下降(P0. 05),与对照组组间比较差异无统计学意义。治疗后两组类风湿因子与本组治疗前比较均无明显下降。治疗组不良反应率1. 75%(1/57),对照组不良反应发生率为25. 49%(13/51)。结论:与硫酸羟氯喹相比,益胃汤加味方治疗pSS,可明显改善患者疲劳及总体症状,两者均可降低血清IgG,益胃汤加味方组疗效较硫酸羟氯喹更明显。两组药物对pSS患者RF水平均无明显影响。长期用药,益胃汤加味方治疗pSS较硫酸羟氯喹更为安全。 相似文献
48.
目的研制加强型鼻咽通气道应用于五官科鼻腔手术后的气道管理。方法选取2014年1月至2015年3月行五官科鼻腔手术的患者60例,将其分为A组和B组,各30例。A组作为加强型鼻咽通气道组,术毕在膨胀止血海绵中放置加强型鼻咽通气道保留鼻腔通气;B组作为对照组,术毕采用传统单纯填塞膨胀止血海绵。通过术后24、48 h随访,对两组患者进行疼痛、睡眠质量、口干程度评分,并对其进行对比分析。结果加强型鼻咽通气道具有良好的抗压抗折性;A组患者24、48 h睡眠质量、口干程度评分均明显优于B组,差异均有统计学意义(P<0.05)。结论加强型鼻咽通气道用于五官科鼻腔手术后气道管理可增强气道管理安全性及患者舒适度。 相似文献
49.
The objective of the present study was to evaluate the clinical, radiological, and functional outcomes of a subscapularis transthoracic surgical approach and a posterolateral surgical approach with debridement, bone graft fusion, and internal fixation for the treatment of upper thoracic tuberculosis.There is currently debate over the best surgical approach for the treatment of upper thoracic tuberculosis. Traditionally, the subscapularis transthoracic approach has been preferred; however, the posterolateral approach has gained popularity in the past few years.A prospective, consecutive cohort of 43 upper thoracic tuberculosis patients with a mean age of 39 years (range: 20–52 years) was followed up for a minimum of 12 months (range: 12–60 months). Patients were randomly divided into 2 groups. Group A (n = 21) was treated by the subscapularis transthoracic approach and group B (n = 22) was treated by the posterolateral approach. All cases were evaluated for clinical, radiological, and functional outcomes. Intraoperative blood loss, operative duration, intraoperative and postoperative complications, hospital stay, the cure rate, fusion time, and the Frankel scale were used for clinical and functional evaluation, whereas the kyphosis angle was used for radiological evaluation.Grafted bones were fused by 10 months in all cases. There was no statistically significant difference between groups before surgery in terms of gender, age, segmental tuberculosis, erythrocyte sedimentation rate (ESR), Frankel scale, or Cobb''s angle (P > 0.05). The average operative duration for Group B was lower than that of Group A. There were no significant differences in intraoperative blood loss, intraoperative and postoperative complications, hospital stay, grafted bone fusion time, or cure rate between groups (P > 0.05). The Cobb''s angle correction rate for group B (68.5%) was significantly better than that of group A (30.9%). The neurological score showed significant postoperative improvement in both groups, with no significant difference between the groups.The subscapularis transthoracic approach and the posterolateral approach with debridement, bone graft fusion, and internal fixation are both sufficient and satisfactory for the surgical treatment of upper thoracic tuberculosis. However, the posterolateral approach is superior to the subscapularis transthoracic approach in terms of surgical trauma, operative time, and kyphosis correction. 相似文献