全文获取类型
收费全文 | 40410篇 |
免费 | 2884篇 |
国内免费 | 1002篇 |
专业分类
耳鼻咽喉 | 517篇 |
儿科学 | 1200篇 |
妇产科学 | 282篇 |
基础医学 | 3876篇 |
口腔科学 | 229篇 |
临床医学 | 5976篇 |
内科学 | 13414篇 |
皮肤病学 | 181篇 |
神经病学 | 3589篇 |
特种医学 | 1017篇 |
外科学 | 3005篇 |
综合类 | 4866篇 |
现状与发展 | 1篇 |
一般理论 | 1篇 |
预防医学 | 917篇 |
眼科学 | 607篇 |
药学 | 3021篇 |
14篇 | |
中国医学 | 931篇 |
肿瘤学 | 652篇 |
出版年
2024年 | 33篇 |
2023年 | 571篇 |
2022年 | 714篇 |
2021年 | 1453篇 |
2020年 | 1418篇 |
2019年 | 1528篇 |
2018年 | 1438篇 |
2017年 | 1055篇 |
2016年 | 989篇 |
2015年 | 1153篇 |
2014年 | 2387篇 |
2013年 | 2362篇 |
2012年 | 1786篇 |
2011年 | 2101篇 |
2010年 | 1804篇 |
2009年 | 1716篇 |
2008年 | 1908篇 |
2007年 | 1972篇 |
2006年 | 1738篇 |
2005年 | 1525篇 |
2004年 | 1322篇 |
2003年 | 1153篇 |
2002年 | 1033篇 |
2001年 | 964篇 |
2000年 | 877篇 |
1999年 | 845篇 |
1998年 | 787篇 |
1997年 | 793篇 |
1996年 | 663篇 |
1995年 | 578篇 |
1994年 | 536篇 |
1993年 | 477篇 |
1992年 | 489篇 |
1991年 | 447篇 |
1990年 | 385篇 |
1989年 | 311篇 |
1988年 | 310篇 |
1987年 | 295篇 |
1986年 | 284篇 |
1985年 | 360篇 |
1984年 | 302篇 |
1983年 | 242篇 |
1982年 | 251篇 |
1981年 | 211篇 |
1980年 | 184篇 |
1979年 | 148篇 |
1978年 | 113篇 |
1977年 | 68篇 |
1976年 | 67篇 |
1973年 | 31篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
1.
2.
《Clinical neurophysiology》2021,132(9):2003-2011
ObjectiveA large N20 and P25 of the median nerve somatosensory evoked potential (SEP) predicts short survival in amyotrophic lateral sclerosis (ALS). We investigated whether high frequency oscillations (HFOs) over N20 are enlarged and associated with survival in ALS.MethodsA total of 145 patients with ALS and 57 healthy subjects were studied. We recorded the median nerve SEP and measured the onset-to-peak amplitude of N20 (N20o-p), and peak-to-peak amplitude between N20 and P25 (N20p-P25p). We obtained early and late HFO potentials by filtering SEP between 500 and 1 kHz, and measured the peak-to-peak amplitude. We followed up patients until endpoints (death or tracheostomy) and analyzed the relationship between SEP or HFO amplitudes and survival using a Cox analysis.ResultsPatients showed larger N20o-p, N20p-P25p, and early and late HFO amplitudes than the control values. N20p-P25p was associated with survival periods (p = 0.0004), while early and late HFO amplitudes showed no significant association with survival (p = 0.4307, and p = 0.6858, respectively).ConclusionsThe HFO amplitude in ALS is increased, but does not predict survival.SignificanceThe enlarged HFOs in ALS might be a compensatory phenomenon to the hyperexcitability of the sensory cortex pyramidal neurons. 相似文献
3.
4.
5.
6.
7.
8.
9.
《Clinical neurophysiology》2020,131(1):259-264
ObjectivesFasciculation potentials (FP) are an important consideration in the electrophysiological diagnosis of ALS. Muscle ultrasonography (MUS) has a higher sensitivity in detecting fasciculations than electromyography (EMG), while in some cases, it is unable to detect EMG-detected fasciculations. We aimed to investigate the differences of FP between the muscles with and without MUS-detected fasciculations (MUS-fas).MethodsThirty-one consecutive patients with sporadic ALS were prospectively recruited and in those, both needle EMG and MUS were performed. Analyses of the amplitude, duration, and number of phases of EMG-detected FPs were performed for seven muscles per patient, and results were compared between the muscles with and without MUS-fas in the total cohort.ResultsThe mean amplitude and phase number of FP were significantly lower in patients with EMG-detected FP alone (0.39 ± 0.25 mV and 3.21 ± 0.88, respectively) than in those with both FP and MUS-fas (1.22 ± 0.92 mV and 3.74 ± 1.39, respectively; p < 0.0001 and p = 0.017, Welch’s t-test).ConclusionSmall FP may be undetectable with MUS. MUS cannot replace EMG in the diagnostic approach for ALS.SignificanceClinicians should use a combination of EMG and MUS for the detection and quantitative analysis of fasciculation in ALS. 相似文献