全文获取类型
收费全文 | 4759篇 |
免费 | 435篇 |
国内免费 | 4篇 |
出版年
2022年 | 40篇 |
2021年 | 75篇 |
2020年 | 26篇 |
2019年 | 39篇 |
2018年 | 63篇 |
2017年 | 48篇 |
2016年 | 113篇 |
2015年 | 242篇 |
2014年 | 250篇 |
2013年 | 312篇 |
2012年 | 432篇 |
2011年 | 379篇 |
2010年 | 201篇 |
2009年 | 176篇 |
2008年 | 235篇 |
2007年 | 244篇 |
2006年 | 231篇 |
2005年 | 211篇 |
2004年 | 198篇 |
2003年 | 171篇 |
2002年 | 162篇 |
2001年 | 148篇 |
2000年 | 136篇 |
1999年 | 106篇 |
1998年 | 50篇 |
1997年 | 39篇 |
1996年 | 40篇 |
1995年 | 30篇 |
1994年 | 30篇 |
1993年 | 31篇 |
1992年 | 70篇 |
1991年 | 70篇 |
1990年 | 59篇 |
1989年 | 61篇 |
1988年 | 58篇 |
1987年 | 60篇 |
1986年 | 37篇 |
1985年 | 20篇 |
1984年 | 31篇 |
1983年 | 22篇 |
1982年 | 14篇 |
1981年 | 17篇 |
1979年 | 26篇 |
1978年 | 23篇 |
1977年 | 14篇 |
1976年 | 17篇 |
1975年 | 18篇 |
1974年 | 23篇 |
1973年 | 22篇 |
1972年 | 11篇 |
排序方式: 共有5198条查询结果,搜索用时 15 毫秒
131.
Mouse leukemia L-1210 cells were iodinated with 125I; this permitted the development of a method for the isolation of the plasma membranes. These show a 10- to 16-fold increase in the specific activity of 125I over that of the cell homogenate and a 20-fold increase in the specific activities of 5′-nucleotidase and alkaline phosphate; no mitochondrial or microsomal marker enzyme activities were detected. Sodium dodecyl sulfate gel electrophoresis of the plasma membranes shows approx. 40 peptides with molecular weights ranging from 10 000 to over 200 000; a polypeptide ( 50 000) predominates. Of 13 iodinated surface membrane proteins, the major radioactive peptide has a molecular weight of 85 000. The importance of the selection of the appropriate gel sytem for the analysis of membrane proteins is emphasized. 相似文献
132.
133.
Wu Changwei W. Tsai Pei-Jung Chen Sharon Chia-Ju Li Chia-Wei Hsu Ai-Ling Wu Hong-Yi Ko Yu-Ting Hung Pai-Chuan Chang Chun-Yen Lin Ching-Po Lane Timothy J. Chen Chia-Yuen 《Sleep and biological rhythms》2019,17(4):423-431
Sleep and Biological Rhythms - Neurovascular coupling (NVC), the transient regional hyperemia following the evoked neuronal responses, is the basis of blood oxygenation level-dependent techniques... 相似文献
134.
Shang-Yi Lin Po-Liang Lu Kun-Bow Tsai Chun-Yu Lin Wei-Ru Lin Tun-Chieh Chen Ya-Ting Chang Chung-Hao Huang Chi-Yu Chen Chung-Chih Lai Yen-Hsu Chen 《Mycopathologia》2012,174(5-6):499-504
Mucormycosis is an invasive fungal infection associated with a high mortality rate, especially in immunocompromised hosts. Mucormycosis rarely occurs in cirrhotic patients. Here, we report a case of mucormycosis with underlying liver cirrhosis and diabetes mellitus. The patient suffered from maxillary sinusitis and osteomyelitis, and the infection was successfully treated with antifungal agents, surgical debridement, and hyperbaric oxygen therapy. The antifungal treatments used were liposomal amphotericin B, itraconazole, and posaconazole. Although our patient had liver cirrhosis (Child-Pugh classification B), no hepatic decompensation was developed during the treatment course of posaconazole. This is the first report of the safe and effective use of posaconazole for the treatment of mucormycosis in a cirrhotic patient. 相似文献
135.
Smad Anchor for Receptor Activation (SARA) has been reported as a critical role in TGF-β signal transduction by recruiting non-activated Smad2/3 to the TGF-β receptor and ensuring appropriate subcellular localization of the activated receptor-bound complex. However, controversies still exist in previous reports. In this study, we describe the expression of two SARA isoforms, SARA1 and SARA2, in mice and report the generation and characterization of SARA mutant mice with FYVE domain deletion. SARA mutant mice developed normally and showed no gross abnormalities. Further examination showed that the TGF-β signaling pathway was indeed altered in SARA mutant mice, with the downregulation of Smad2 protein expression. The decreasing expression of Smad2 was caused by enhancing Smurf2-mediated proteasome degradation pathway. However, the internalization of TGF-β receptors into the early endosome was not affected in SARA mutant mouse embryonic fibroblasts (MEFs). Moreover, the downregulation of Smad2 in SARA mutant MEFs was not sufficient to disrupt the diverse cellular biological functions of TGF-β signaling, including growth inhibition, apoptosis, senescence, and the epithelial-to-mesenchymal transition. Our results indicate that SARA is not involved in the activation process of TGF-β signal transduction. Using a two-stage skin chemical carcinogenesis assay, we found that the loss of SARA promoted skin tumor formation and malignant progression. Our data suggest a protective role of SARA in skin carcinogenesis. 相似文献
136.
137.
138.
139.
Hung-Yen Ke Li-Han Chin Chien-Sung Tsai Feng-Zhi Lin Yen-Hui Chen Yung-Lung Chang Shih-Ming Huang Yao-Chang Chen Chih-Yuan Lin 《Journal of cellular and molecular medicine》2020,24(6):3669-3677
Cardiovascular complications are leading causes of morbidity and mortality in patients with chronic kidney disease (CKD). CKD significantly affects cardiac calcium (Ca2+) regulation, but the underlying mechanisms are not clear. The present study investigated the modulation of Ca2+ homeostasis in CKD mice. Echocardiography revealed impaired fractional shortening (FS) and stroke volume (SV) in CKD mice. Electrocardiography showed that CKD mice exhibited longer QT interval, corrected QT (QTc) prolongation, faster spontaneous activities, shorter action potential duration (APD) and increased ventricle arrhythmogenesis, and ranolazine (10 µmol/L) blocked these effects. Conventional microelectrodes and the Fluo-3 fluorometric ratio techniques indicated that CKD ventricular cardiomyocytes exhibited higher Ca2+ decay time, Ca2+ sparks, and Ca2+ leakage but lower [Ca2+]i transients and sarcoplasmic reticulum Ca2+ contents. The CaMKII inhibitor KN93 and ranolazine (RAN; late sodium current inhibitor) reversed the deterioration in Ca2+ handling. Western blots revealed that CKD ventricles exhibited higher phosphorylated RyR2 and CaMKII and reduced phosphorylated SERCA2 and SERCA2 and the ratio of PLB-Thr17 to PLB. In conclusions, the modulation of CaMKII, PLB and late Na+ current in CKD significantly altered cardiac Ca2+ regulation and electrophysiological characteristics. These findings may apply on future clinical therapies. 相似文献
140.
Nader Morshed William T Ralvenius Alexi Nott L Ashley Watson Felicia H Rodriguez Leyla A Akay Brian A Joughin PingChieh Pao Jay Penney Lauren LaRocque Diego Mastroeni LiHuei Tsai Forest M White 《Molecular systems biology》2020,16(12)
Alzheimer’s disease (AD) is characterized by the appearance of amyloid‐β plaques, neurofibrillary tangles, and inflammation in brain regions involved in memory. Using mass spectrometry, we have quantified the phosphoproteome of the CK‐p25, 5XFAD, and Tau P301S mouse models of neurodegeneration. We identified a shared response involving Siglec‐F which was upregulated on a subset of reactive microglia. The human paralog Siglec‐8 was also upregulated on microglia in AD. Siglec‐F and Siglec‐8 were upregulated following microglial activation with interferon gamma (IFNγ) in BV‐2 cell line and human stem cell‐derived microglia models. Siglec‐F overexpression activates an endocytic and pyroptotic inflammatory response in BV‐2 cells, dependent on its sialic acid substrates and immunoreceptor tyrosine‐based inhibition motif (ITIM) phosphorylation sites. Related human Siglecs induced a similar response in BV‐2 cells. Collectively, our results point to an important role for mouse Siglec‐F and human Siglec‐8 in regulating microglial activation during neurodegeneration. 相似文献