全文获取类型
收费全文 | 16247篇 |
免费 | 1483篇 |
国内免费 | 975篇 |
专业分类
耳鼻咽喉 | 146篇 |
儿科学 | 162篇 |
妇产科学 | 283篇 |
基础医学 | 2018篇 |
口腔科学 | 267篇 |
临床医学 | 2153篇 |
内科学 | 2642篇 |
皮肤病学 | 182篇 |
神经病学 | 851篇 |
特种医学 | 567篇 |
外国民族医学 | 5篇 |
外科学 | 1904篇 |
综合类 | 2150篇 |
现状与发展 | 1篇 |
一般理论 | 6篇 |
预防医学 | 1079篇 |
眼科学 | 513篇 |
药学 | 1672篇 |
15篇 | |
中国医学 | 743篇 |
肿瘤学 | 1346篇 |
出版年
2024年 | 45篇 |
2023年 | 243篇 |
2022年 | 579篇 |
2021年 | 795篇 |
2020年 | 551篇 |
2019年 | 546篇 |
2018年 | 561篇 |
2017年 | 502篇 |
2016年 | 495篇 |
2015年 | 723篇 |
2014年 | 877篇 |
2013年 | 818篇 |
2012年 | 1181篇 |
2011年 | 1177篇 |
2010年 | 855篇 |
2009年 | 664篇 |
2008年 | 782篇 |
2007年 | 789篇 |
2006年 | 833篇 |
2005年 | 777篇 |
2004年 | 642篇 |
2003年 | 620篇 |
2002年 | 568篇 |
2001年 | 446篇 |
2000年 | 387篇 |
1999年 | 393篇 |
1998年 | 272篇 |
1997年 | 240篇 |
1996年 | 181篇 |
1995年 | 182篇 |
1994年 | 117篇 |
1993年 | 102篇 |
1992年 | 110篇 |
1991年 | 96篇 |
1990年 | 74篇 |
1989年 | 70篇 |
1988年 | 66篇 |
1987年 | 62篇 |
1986年 | 43篇 |
1985年 | 42篇 |
1984年 | 22篇 |
1983年 | 15篇 |
1981年 | 14篇 |
1980年 | 12篇 |
1979年 | 21篇 |
1976年 | 10篇 |
1974年 | 15篇 |
1973年 | 13篇 |
1972年 | 10篇 |
1969年 | 11篇 |
排序方式: 共有10000条查询结果,搜索用时 78 毫秒
91.
基于扩展Infomax ICA的ERP少次提取方法研究 总被引:1,自引:0,他引:1
事件相关电位(event related potential,ERP)提取是脑电研究的重点之一,目前临床上主要通过相干平均的方法来获取.由于脑电的非平稳性,使其需要大量重复刺激才能获得,对于受试者极不方便,也不利于ERP的实时检测.本文以反映大脑稀少认知事件的相关电位P300为例,采用扩展Infomax(extended informationmaximization)独立分量分析(independent component analysis,ICA)算法,先滤除眼动、工频干扰,再重构脑电数据,最后经少次叠加即可得到与通常需多次相干平均结果相近的比较满意的P300波形.说明ICA算法在ERP的峰值和潜伏期模式识别上具有较为明显的效果,具有潜在的临床工程应用价值. 相似文献
92.
The role of mPer1 in morphine dependence in mice 总被引:6,自引:0,他引:6
Liu Y Wang Y Wan C Zhou W Peng T Liu Y Wang Z Li G Cornelisson G Halberg F 《Neuroscience》2005,130(2):383-388
Investigations using Drosophila melanogaster have shown that the circadian clock gene period can influence behavioral responses to cocaine, and the mouse homologues, mPer1 and mPer2, modulate cocaine sensitization and reward. In the present study, we applied DNAzyme targeting mPer1 to interfere the expression of mPer1 in CNS in mice and studied the role of mPer1 on morphine dependence. We found that the DNAzyme could attenuate the expression of mPer1 in CNS in mice. Mice treated with DNAzyme and morphine synchronously did not show preference to the morphine-trained side, whereas the control group did. In contrast, mice treated with DNAzyme after morphine showed preference to the morphine-trained side as well as the control group did. These results indicate that drug dependence seems to be influenced at least partially by mPer1, but mPer1 cannot affect morphine dependence that has been formed. 相似文献
93.
94.
Ching Shan Wan Jade Mitchell Andrea B. Maier 《Journal of the American Medical Directors Association》2021,22(6):1331.e1-1331.e9
ObjectivesTo evaluate the effect of Hospital Admission Risk Program (HARP) on unplanned hospitalization, bed days, and mortality of enrolled individuals and to evaluate the cost-effectiveness of HARP.DesignA retrospective longitudinal analysis of hospital administrative data.InterventionIndividuals at risk of hospitalization were provided with multidisciplinary, community-based care support managed by care coordinators including integrated care planning, education, monitoring, service linkages, and general practitioner liaison over 6-9 months.Setting and ParticipantsIndividuals who were enrolled into 1 of 8 HARP chronic disease management programs between July 1, 2017, and June 30, 2018, at the Royal Melbourne Hospital, Australia.MethodsHospital admissions between 18 months before and 18 months after HARP enrollment were analyzed. Total hospital costs were compared between 18 months before and 12 months after HARP enrollment.ResultsA total of 1553 individuals with a median age of 71 years (interquartile range 60-81), 63.4% males, were admitted to HARP. Both unplanned hospitalizations and bed days were reduced during the HARP intervention compared to within 3 months before enrollment in each of the HARP management programs. After the HARP intervention, cardiac coach, cardiac heart failure, chronic respiratory, diabetes comanagement, and medication management programs had higher hospitalizations and bed days than individuals’ baseline of at least 3 months before HARP enrollment. Individuals in cardiac heart failure and chronic respiratory management programs had a higher mortality rate than other HARP chronic disease management programs. Individuals in cardiac coach, diabetes comanagement, and medication management programs had lower hospital costs during the HARP intervention compared to within 3 months before HARP enrollment.Conclusions and ImplicationsHARP reduced unplanned hospitalization and bed days but did not return individuals’ hospital use to baseline before the intervention. The variations in mortality between HARP chronic disease management programs implies that condition-specific goals between programs is preferable. 相似文献
95.
Pyoeng Gyun Choe Chang Kyung Kang Hyeon Jeong Suh Jongtak Jung Kyoung-Ho Song Ji Hwan Bang Eu Suk Kim Hong Bin Kim Sang Won Park Nam Joong Kim Wan Beom Park Myoung-don Oh 《Emerging infectious diseases》2021,27(1):327
We investigated the kinetics of severe acute respiratory syndrome coronavirus 2 neutralizing antibodies in 7 asymptomatic persons and 11 patients with pneumonia. The geometric mean titer of neutralizing antibodies declined from 219.4 at 2 months to 143.7 at 5 months after infection, indicating a waning antibody response. 相似文献
97.
目的:探讨治疗创伤对高血压性脑出血患者血糖及按期预后的影响。方法:采用局麻血肿穿刺抽吸治疗(治疗组32例)及全麻外科手术血肿清除治疗(对照组30例),比较术后的血糖变化,结果:治疗组血肿穿刺抽吸后血糖高峰值水平显著低于对照组(P<0.01),而治疗后第1,2,周血糖降至正常者治疗组显著高于对照组(P<0.05),病死率治疗组6.25%,对照组26.7%),两组比较差异显著(P<0.05),结论:高血压性脑出血患者血肿穿刺抽吸治疗较外科手术血肿清除治疗有血糖峰值低,恢复正常的速度快,病死率低,对脑组织的损伤小等优点,值得临床推广。 相似文献
98.
目的:通过对骨髓单个核细胞在体外与不同细胞因子培养,了解不同细胞因子对骨髓淋巴细胞的激活能力和对骨髓干祖细胞的损伤情况。方法:将IL-1、IL-2、γ-IFN、CD3单抗进行不同组合后,在体外与骨髓单个核细胞分成对照组、IL-2组、CD3-AK、CIK组进行培养。培养过程中观察细胞形态和数量的变化,并在培养后检测免疫活性细胞的细胞毒性和造血干细胞的保存情况。结果:培养过程中对照组细胞数量减少;IL-2组细胞数量变化不明显;CD3-AK组、CIK组细胞数量显著增多,并出现较多的集聚成簇的淋巴样细胞,培养后其细胞毒性明显强于对照组及IL-2组,但细胞数量增加和细胞毒性无明性差异,培养后各组造血干细胞保存情况约16%~87%。结论:IL-2、CD3单抗在体外与骨髓单个核细胞培养后,即能激活免疫细胞增殖,又能保留足够的造血干细胞。 相似文献
99.
夹竹桃水提物灭螺活性研究 总被引:3,自引:0,他引:3
目的 研究夹竹桃水提物的灭螺活性。方法 测试水提物作用后钉螺的死亡率,用直线回归法进行量效和时效分析。结果 夹竹桃水提物灭螺的量效和时效关系分别为Y=95.4378D-21.2478和Y=21.32T-3.96,pH从5.5到8.5的范围内其活性随pH上升略有下降,室内贮存1年及100℃加热2h其活性基本不变。结论 夹竹桃水提物具有很强的灭螺活性。 相似文献
100.
功能性鼻窦内窥镜手术100例疗效观察 总被引:1,自引:0,他引:1
目的:功能性鼻窦内窥镜手术的长期疗效。方法:采用Messerklinger术式为100例患者手术;并以传统术式治疗100例作对照。结果:内窥镜组临床治愈率81%,总有效率95%,明显优于传统手术组(P<0.05),手术并发症发生率为6%,明显低于传统组(P<0.05)。结论:内窥镜手术长期疗效可靠,并发症少,复发率低。 相似文献