全文获取类型
收费全文 | 387542篇 |
免费 | 26255篇 |
国内免费 | 8423篇 |
专业分类
耳鼻咽喉 | 4307篇 |
儿科学 | 11799篇 |
妇产科学 | 7318篇 |
基础医学 | 32326篇 |
口腔科学 | 8875篇 |
临床医学 | 43875篇 |
内科学 | 49962篇 |
皮肤病学 | 5220篇 |
神经病学 | 20210篇 |
特种医学 | 8636篇 |
外国民族医学 | 32篇 |
外科学 | 41856篇 |
综合类 | 57265篇 |
现状与发展 | 19篇 |
一般理论 | 29篇 |
预防医学 | 44458篇 |
眼科学 | 5574篇 |
药学 | 33946篇 |
430篇 | |
中国医学 | 31509篇 |
肿瘤学 | 14574篇 |
出版年
2023年 | 6334篇 |
2022年 | 11372篇 |
2021年 | 15494篇 |
2020年 | 14620篇 |
2019年 | 20052篇 |
2018年 | 17551篇 |
2017年 | 14442篇 |
2016年 | 12105篇 |
2015年 | 11586篇 |
2014年 | 22870篇 |
2013年 | 24931篇 |
2012年 | 21291篇 |
2011年 | 22872篇 |
2010年 | 18083篇 |
2009年 | 16593篇 |
2008年 | 16142篇 |
2007年 | 16636篇 |
2006年 | 14718篇 |
2005年 | 12793篇 |
2004年 | 10439篇 |
2003年 | 9140篇 |
2002年 | 7081篇 |
2001年 | 6388篇 |
2000年 | 5278篇 |
1999年 | 4638篇 |
1998年 | 3759篇 |
1997年 | 3574篇 |
1996年 | 3097篇 |
1995年 | 2979篇 |
1994年 | 2858篇 |
1993年 | 2288篇 |
1992年 | 2281篇 |
1991年 | 2004篇 |
1990年 | 1729篇 |
1989年 | 1568篇 |
1988年 | 1457篇 |
1987年 | 1247篇 |
1985年 | 3921篇 |
1984年 | 4876篇 |
1983年 | 3407篇 |
1982年 | 3871篇 |
1981年 | 3601篇 |
1980年 | 3193篇 |
1979年 | 2950篇 |
1978年 | 2559篇 |
1977年 | 1931篇 |
1976年 | 2183篇 |
1975年 | 1646篇 |
1974年 | 1435篇 |
1973年 | 1287篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
101.
Michael D. Cabana David Bruckman Susan L. Bratton Alex R. Kemper Noreen M. Clark 《The Journal of asthma》2003,40(7):741-749
Background. The National Heart, Lung, and Blood Institute (NHLBI) guidelines recommend that patients receive a follow-up outpatient asthma visit after being discharged from an emergency department (ED) for asthma. Objective. To measure the frequency of follow-up outpatient asthma visits and its association with repeat ED asthma visit. Design. We conducted a retrospective cohort study of children with asthma using claims data from a university-based managed care organization from 01 1998 to 10 2000. We performed a multivariate survival analysis using Cox proportional hazards model to determine the effect of follow-up outpatient asthma visits on the likelihood of a repeat ED asthma visit, after controlling for severity of illness, patient age, gender, insurance, and the specialty of the primary care provider. Results: A total of 561 children had 780 ED asthma visits. Of these, 103 (17%) had a repeat ED asthma visit within 1 year. Almost two-thirds of children (66%) did not receive outpatient follow-up for asthma within 30 days of an ED asthma visit. Outpatient asthma visits within 30 days of an ED asthma visit are associated with an increased likelihood (relative risk = 1.80; 95% confidence interval 1.19, 2.72) for repeat ED asthma visits within 1 year. Conclusions. Most patients do not have outpatient follow-up after an ED asthma visit. However, those patients that present for outpatient follow-up have an increased likelihood for repeat ED asthma visits. For the primary care provider, these outpatient follow-up visits signal an increased risk that a patient will return to the ED for asthma and are a key opportunity to prevent future ED asthma visits. 相似文献
102.
TUVP手术时间对血红蛋白及电解质的影响 总被引:2,自引:0,他引:2
目的 了解经尿道前列腺汽化电切手术时间对血红蛋白及血清电解质的影响。方法 对64例经尿道前列腺汽化电切术患按手术时间分组,观察手术前后血红蛋白及血清电解质的变化。结果 手术时间对血清电解质的降低有的影响,对血红蛋白降低的影响不显。结论 减少TUR综合征的关键是要操作熟练,缩短手术时间及手术中注意止血。 相似文献
103.
Foley尿管气囊压迫治疗骶前静脉丛大出血的评价(附6例报告) 总被引:5,自引:0,他引:5
目的:评价直肠癌根治术中用Foley尿管气囊压迫治疗骶前静脉丛大出血(MPVP)的临床价值。方法:分析1995~2005年用Foley尿管气囊压迫治疗骶前静脉丛大出血6例的临床资料。结果:6例骶前大出血中全部用Foley尿管气囊压迫控制出血,术中出血量为800~1700mL,Foley尿管于术后4d拔除3例,5d1例,6d2例,均无再出血,会阴切口均一期愈合。结论:Foley尿管气囊压迫治疗骶前静脉丛大出血是一种简单安全有效的治疗方法。 相似文献
104.
R W Tennant 《Environmental and molecular mutagenesis》1991,18(4):322-323
The development of transgenic mouse lines with target genes that are suitable for tissue-specific mutagenesis studies is an important contribution to the field of environmental mutagenesis. These models can accommodate many of the questions relating to metabolism, distribution and relative potency of mutagens as well as providing a more comprehensive system for the identification of mutagens. However, the lesions that the field has learned about methods, development and validation from the use of in vitro systems must be applied to the development and validation of transgenic models. 相似文献
105.
处女膜修补手术及麻醉方法的改进 总被引:9,自引:7,他引:2
目的;增大处女膜粘膜瓣的接触面,减少因麻醉造成的处女膜粘膜水肿,提高修复手术的成功率。方法:手术全部采用1%的卡因行粘膜表面麻醉。53例采用瓦合粘膜瓣法,3例用瓦合粘膜瓣联合阴道粘膜瓣修复法。结果:56例术后一月随访,53例处女膜孔径为一指,成功率94.64%。结论:采用1%的卡因粘膜表面麻醉,瓦合粘膜瓣法及瓦合粘膜联合阴道粘膜瓣修复法对处女膜修复是行之有效的。 相似文献
106.
Imad Ghorayeb MD PhD Anderson Loundou PhD Pascal Auquier MD Yves Dauvilliers MD PhD Bernard Bioulac MD PhD François Tison MD PhD 《Movement disorders》2007,22(11):1567-1572
To determine the prevalence of excessive daytime sleepiness (EDS) and that of dozing and sudden onset of sleep episodes (SOS) while driving in ambulatory patients with Parkinson's disease (PD) in France, a national sample of private and public neurologists was asked to recruit the first 10 consecutive nondemented PD patients. Each patient completed a questionnaire including the Epworth Sleepiness Scale (ESS) and the likelihood of dozing off and experiencing SOS episodes behind the wheel. Clinical and demographic data were collected. One thousand six hundred and twenty‐five patients with PD were included in the survey. Twenty‐nine percent of the patients suffered from EDS (ESS score ≥10) but only 0.8% declared a high chance of dozing while driving and 0.5% reported totally unpredictable SOS episodes while driving. Risk factors for EDS were male gender, reduced activity of daily living, and a high daily levodopa equivalent dosage. Risk factors for SOS episodes while driving were an ESS score ≥10, male gender, and low Hoehn and Yahr staging. EDS is common in ambulatory patients with PD and is a major risk factor for dozing and for SOS episodes behind the wheel in patients who drive. © 2007 Movement Disorder Society 相似文献
107.
腺性膀胱炎三种治疗方法治疗效果的随访观察 总被引:2,自引:0,他引:2
目的 比较腺性膀胱炎三种治疗方法的效果。方法 86例腺性膀胱炎患者分别行膀胱药物灌注、经尿道电切、经尿道电切加膀胱药物灌注治疗。随访观察症状缓解程度和膀胱镜病检结果 1年。结果 73例完成了随访调查 ,占 84.9%。三种方法治疗后症状缓解程度 ,差异无显著性意义 (P >0 .0 5 ) ;膀胱镜病检复查 ,灌注治疗效果好于电切治疗效果 ,综合治疗效果好于电切治疗效果 ,差异具有显著性意义 ;比较灌注治疗后膀胱镜病检阴性例数 ( 2 2 /2 8)与综合治疗后膀胱镜病检阴性例数 ( 3 0 /3 4) ,差异无显著性意义 ( χ2 =1.0 60 ,P =0 .3 0 3 )。结论 膀胱药物灌注和经尿道电切加膀胱药物灌注的膀胱镜病检复查 ,效果好于电切治疗的效果。 相似文献
108.
T. Hammen F. Kerling M. Schwarz A. Stadlbauer O. Ganslandt B. Keck B. Tomandl A. Dörfler H. Stefan 《European journal of neurology》2006,13(5):482-490
Up to 30% of patients with temporal lobe epilepsy (TLE) remain without remarkable changes in MRI. In this study we investigated the role of (1)H-MR spectroscopy ((1)H-MRS) in lateralizing the affected hemisphere in the mentioned patient group. Twenty-two consecutive patients diagnosed with TLE were investigated by high resolution MRI and (1)H-MRS. We examined the incidence and diagnostic accuracy of temporal metabolite alterations determined by Linear Combination of Model Spectra (L C Model) via water reference. Metabolite values of each hemisphere of TLE patients were compared with healthy controls. Results of metabolite alterations were related to intensive video EEG focus localization. Reduction of N-acetylaspartate + N-acetylaspartyl-glutamate (tNAA) in the affected hemisphere revealed identification in six of nine patients (66%) with unilateral TLE. Group comparison revealed a significant reduction of tNAA (6.1+/-0.8*) in the involved temporal lobe compared with controls (6.67+/-0.4*, P=0.026). Choline levels were significantly increased in the affected hemisphere (1.42+/-0.17*) compared with healthy controls (1.22+/-0.17*, P=0.035). The results of our study show that (1)H-MRS is able to identify the affected hemisphere of MRI negative TLE patients and can be used as an additive tool in multimodal focus localization. 相似文献
109.
用外耳道外沿皮下缝合法制备了一种新的单侧听觉气传导持续阻滞大鼠模型。它具有制作简便、损伤较小、效果持续的优点。 相似文献
110.
The intrauterine position occupied by a rodent fetus influences the amount of testosterone to which it is exposed before birth. Animals that are gestated between two male fetuses (2M) are exposed to higher circulating levels of testosterone than are animals positioned between two female fetuses (2F) and there are reliable differences in the reproductive physiology and behavior of 2M and 2F animals when adult. To determine whether intrauterine position modifies development of the central nervous system, we examined the sexually dimorphic spinal nucleus of the bulbocavernosus (SNB) in male and female gerbils from known intrauterine positions. We found that adult 2M female gerbils had 16% more SNB motoneurons than did 2F females. 2M males did not differ from 2F males in SNB motoneuron number, but the bulbocavernosus muscle, which is innervated by SNB motoneurons, was approximately 50% larger in 2M than in 2F males. These data indicate that intrauterine position can influence the morphology of the sexually dimorphic SNB neuromuscular system. 相似文献