全文获取类型
收费全文 | 19839篇 |
免费 | 2522篇 |
国内免费 | 9篇 |
出版年
2021年 | 248篇 |
2019年 | 208篇 |
2018年 | 246篇 |
2017年 | 215篇 |
2016年 | 378篇 |
2015年 | 582篇 |
2014年 | 682篇 |
2013年 | 800篇 |
2012年 | 974篇 |
2011年 | 1029篇 |
2010年 | 680篇 |
2009年 | 647篇 |
2008年 | 880篇 |
2007年 | 836篇 |
2006年 | 740篇 |
2005年 | 772篇 |
2004年 | 774篇 |
2003年 | 730篇 |
2002年 | 678篇 |
2001年 | 551篇 |
2000年 | 594篇 |
1999年 | 512篇 |
1998年 | 248篇 |
1997年 | 249篇 |
1996年 | 225篇 |
1995年 | 221篇 |
1994年 | 219篇 |
1993年 | 209篇 |
1992年 | 421篇 |
1991年 | 411篇 |
1990年 | 413篇 |
1989年 | 355篇 |
1988年 | 347篇 |
1987年 | 319篇 |
1986年 | 277篇 |
1985年 | 305篇 |
1984年 | 265篇 |
1983年 | 244篇 |
1982年 | 204篇 |
1981年 | 204篇 |
1980年 | 200篇 |
1979年 | 268篇 |
1978年 | 222篇 |
1977年 | 199篇 |
1976年 | 198篇 |
1975年 | 194篇 |
1974年 | 190篇 |
1973年 | 209篇 |
1972年 | 191篇 |
1971年 | 178篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
941.
942.
943.
Phyllis T. Johnson 《Journal of invertebrate pathology》1977,29(2):201-209
A disease of the blue crab caused by a cytoplasmic virus morphologically resembling reovirus is described. Crabs infected with the virus were collected both from a low-salinity tributary of Chesapeake Bay, Maryland, and from Chicoteague Bay, Virginia, a high-salinity area. Virus occurs with greatest frequency in cells of the hemopoietic tissue and in hyaline hemocytes. It is also found in epidermis and gill epithelia and within the neurilemma where it occurs in granulocytes and other cells of uncertain identity. The following diseases are considered in the differential diagnosis of the viral infection: paramoebiasis, bacterial infection, microsporidan infection, Hematodinium infection, and disease caused by a herpes-like virus. 相似文献
944.
945.
946.
B Lynn 《Acta physiologica Hungarica》1987,69(3-4):287-294
Capsaicin has now been shown to have a neurotoxic action on C-fibres in adult rodents and several other mammalian species. In the adult the effect is preferentially on nociceptive C-fibres. The hypoalgesia and loss of neurogenic inflammation that follow capsaicin treatment are likely to be a direct consequence of the C-fibre loss. In addition to its long-term toxic action, capsaicin also has an immediate effect on conduction in nociceptive C-fibres. This action probably produces the short-term hypoalgesia and loss of antidromic plasma extravasation that follow application of capsaicin to peripheral nerves. 相似文献
947.
948.
949.
Kristofer E. Bouchard David F. Conant Gopala K. Anumanchipalli Benjamin Dichter Kris S. Chaisanguanthum Keith Johnson Edward F. Chang 《PloS one》2016,11(3)
A complete neurobiological understanding of speech motor control requires determination of the relationship between simultaneously recorded neural activity and the kinematics of the lips, jaw, tongue, and larynx. Many speech articulators are internal to the vocal tract, and therefore simultaneously tracking the kinematics of all articulators is nontrivial—especially in the context of human electrophysiology recordings. Here, we describe a noninvasive, multi-modal imaging system to monitor vocal tract kinematics, demonstrate this system in six speakers during production of nine American English vowels, and provide new analysis of such data. Classification and regression analysis revealed considerable variability in the articulator-to-acoustic relationship across speakers. Non-negative matrix factorization extracted basis sets capturing vocal tract shapes allowing for higher vowel classification accuracy than traditional methods. Statistical speech synthesis generated speech from vocal tract measurements, and we demonstrate perceptual identification. We demonstrate the capacity to predict lip kinematics from ventral sensorimotor cortical activity. These results demonstrate a multi-modal system to non-invasively monitor articulator kinematics during speech production, describe novel analytic methods for relating kinematic data to speech acoustics, and provide the first decoding of speech kinematics from electrocorticography. These advances will be critical for understanding the cortical basis of speech production and the creation of vocal prosthetics. 相似文献
950.