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951.
952.
Karen R. Lips Patricia A. Burrowes Joseph R. Mendelson Gabriela Parra‐Olea 《Biotropica》2005,37(2):163-165
Amphibian populations are in decline throughout Latin America; all families of frogs have experienced declines, but the species associated with aquatic habitats in upland areas have been most affected. Declines in Latin America were most common during the 1980s, but new declines continue to be reported. The causes of declines are varied, but they have most often been associated with habitat loss, a pathogenic fungus, and climate change. Scientists are just beginning to grasp the ethical and biological implications of losses of this magnitude. In this Special Section, we provide a general summary of the phenomenon and introduce five contributed papers that provide new data and new insights into Latin American declines. 相似文献
953.
The aim of this paper is to prove the uniqueness of isolated periodic solutions (i.e. limit cycles) in two simple models
for microparasitic and macroparasitic diseases. Both models are described by systems of planar autonomous ordinary differential
equations. After transformation of these systems to generalized Liénard systems, we will apply a modified theorem of Zhang
and Dulac’s criterion to prove the uniqueness of limit cycles.
Received 27 February; received in revised form 19 May 1997 相似文献
954.
In order to clarify the transmission process of human immunodeficiency virus type 1 (HIV-1) through the epithelial cell barrier, HeLa cells susceptible and non-susceptible to HIV-1 were cloned and designated as P6 HeLa and N7 HeLa cells, respectively. P6 HeLa cells could be infected with the LAI strain of HIV-1 and mediated HIV-1 transcytosis. In contrast, N7 HeLa cells exhibited neither HIV-1 infection nor transcytosis. CD4 and galactosylceramide as the receptors for HIV-1 were not detected on P6 HeLa cells, although an anti-CD4 monoclonal antibody (mAb) blocked HIV-1 infection. Since HIV-1-infected P6 HeLa cells exhibited no fusion and survived, we speculated that the P6 HeLa cells expressed molecules other than CD4 which facilitated HIV-1 infection. Two mAbs (A-14 ITK and C57 a9-9) which inhibited the HIV-1 infection of P6 HeLa cells were generated. Each mAb recognized distinct molecule(s) as shown by Western blotting. Transcytosis by the P6 HeLa cells was inhibited by C57 a9-9 but not by A-14 ITK or anti-CD4 mAb. Both infection and transcytosis may be responsible for HIV-1 transmission through epithelial cells in a complex manner. Although infection and transcytosis occurred via different mechanisms, the molecule(s) recognized by C57 a9-9 mAb may be associated with both processes. 相似文献
955.
F.-Nora Vögtle Björn Brändl Austin Larson Manuela Pendziwiat Marisa W. Friederich Susan M. White Alice Basinger Cansu Kücükköse Hiltrud Muhle Johanna A. Jähn Oliver Keminer Katherine L. Helbig Carolyn F. Delto Lisa Myketin Dirk Mossmann Nils Burger Noriko Miyake Audrey Burnett Ingo Helbig 《American journal of human genetics》2018,102(4):557-573
956.
Vacuolated PAS‐positive lymphocytes as an hallmark of Pompe disease and other myopathies related to impaired autophagy 下载免费PDF全文
Angelo Pascarella Chiara Terracciano Olimpia Farina Luca Lombardi Teresa Esposito Filomena Napolitano Giuseppina Franzese Giovanni Panella Francesco Tuccillo Giancarlo la Marca Sergio Bernardini Silvia Boffo Antonio Giordano Giuseppe Di Iorio Mariarosa A.B. Melone Simone Sampaolo 《Journal of cellular physiology》2018,233(8):5829-5837
957.
The diagnostic and prognostic value of circulating microRNAs in coronary artery disease: A novel approach to disease diagnosis of stable CAD and acute coronary syndrome 下载免费PDF全文
958.
959.
《Journal of lipid research》2018,59(1):69-78
Vascular calcification is the deposition of mineral in the artery wall by vascular smooth muscle cells (VSMCs) in response to pathological stimuli. The process is similar to bone formation and is an independent risk factor for cardiovascular disease. Given that ceramide and sphingosine 1-phosphate (S1P) are involved in cardiovascular pathophysiology and biomineralization, their role in VSMC matrix mineralization was investigated. During phosphate-induced VSMC mineralization, endogenous S1P levels increased accompanied by increased sphingosine kinase (SK) activity and increased mRNA expression of SK1 and SK2. Consistent with this, mineralization was increased by exogenous S1P, but decreased by C2-ceramide. Mechanistically, exogenous S1P stimulated ezrin-radixin-moesin (ERM) phosphorylation in VSMCs and ERM phosphorylation was increased concomitantly with endogenous S1P during mineralization. Moreover, inhibition of acid sphingomyelinase and ceramidase with desipramine prevented increased S1P levels, ERM activation, and mineralization. Finally, pharmacological inhibition of ERM phosphorylation with NSC663894 decreased mineralization induced by phosphate and exogenous S1P. Although further studies will be needed to verify these findings in vivo, this study defines a novel role for the SK-S1P-ERM pathways in phosphate-induced VSMC matrix mineralization and shows that blocking these pathways with pharmacological inhibitors reduces mineralization. These results may inform new therapeutic approaches to inhibit or delay vascular calcification. 相似文献
960.