全文获取类型
收费全文 | 502篇 |
免费 | 42篇 |
出版年
2024年 | 3篇 |
2023年 | 3篇 |
2022年 | 10篇 |
2021年 | 18篇 |
2020年 | 12篇 |
2019年 | 12篇 |
2018年 | 11篇 |
2017年 | 9篇 |
2016年 | 10篇 |
2015年 | 23篇 |
2014年 | 31篇 |
2013年 | 34篇 |
2012年 | 33篇 |
2011年 | 29篇 |
2010年 | 18篇 |
2009年 | 20篇 |
2008年 | 16篇 |
2007年 | 28篇 |
2006年 | 21篇 |
2005年 | 19篇 |
2004年 | 14篇 |
2003年 | 24篇 |
2002年 | 23篇 |
2001年 | 11篇 |
2000年 | 8篇 |
1999年 | 9篇 |
1998年 | 4篇 |
1996年 | 5篇 |
1995年 | 4篇 |
1994年 | 4篇 |
1993年 | 6篇 |
1992年 | 5篇 |
1991年 | 7篇 |
1990年 | 5篇 |
1989年 | 5篇 |
1988年 | 5篇 |
1987年 | 2篇 |
1986年 | 3篇 |
1985年 | 3篇 |
1983年 | 3篇 |
1982年 | 5篇 |
1981年 | 2篇 |
1980年 | 4篇 |
1979年 | 2篇 |
1978年 | 2篇 |
1977年 | 4篇 |
1975年 | 3篇 |
1971年 | 3篇 |
1970年 | 2篇 |
1966年 | 2篇 |
排序方式: 共有544条查询结果,搜索用时 15 毫秒
91.
92.
93.
94.
95.
Ramin Ekhteiari Salmas Serdar Durdagi Mehmet Fuat Gulhan Merve Duruyurek Huda I. Abdullah 《Journal of biomolecular structure & dynamics》2018,36(3):609-620
The objective of the present study was to evaluate the effects of propolis, pollen, and caffeic acid phenethyl ester (CAPE) on tyrosine hydroxylase (TH) activity and total RNA levels of Nω-nitro-L-arginine methyl ester (L-NAME) inhibition of nitric oxide synthase in the heart, adrenal medulla, and hypothalamus of hypertensive male Sprague dawley rats. The TH activity in the adrenal medulla, heart, and hypothalamus of the rats was significantly increased in the L-NAME group vs. control (p < 0.05). Treatment with L-NAME led to a significant increase in blood pressure (BP) in the L-NAME group compared to control (p < 0.05). These data suggest that propolis, pollen, and CAPE may mediate diminished TH activity in the heart, adrenal medulla, and hypothalamus in hypertensive rats. The decreased TH activity may be due to the modulation and synthesis of catecholamines and BP effects. In addition, the binding mechanism of CAPE within the catalytic domain of TH was investigated by means of molecular modeling approaches. These data suggest that the amino acid residues, Glu429 and Ser354 of TH may play a pivotal role in the stabilization of CAPE within the active site as evaluated by molecular dynamics (MD) simulations. Gibbs binding free energy (ΔGbinding) of CAPE in complex with TH was also determined by post-processing MD analysis approaches (i.e. Poisson-Boltzmann Surface Area (MM-PBSA) method). 相似文献
96.
Amitabha Mazumder Elizabeth A. Grimm Steven A. Rosenberg 《Cancer immunology, immunotherapy : CII》1998,15(1):1-10
Summary We have previously demonstrated that cancer patients' peripheral blood lymphocytes (PBL) allosensitized against single or pool normal donor PBL are capable of lysing fresh autologous tumor cells in a 4-h 51Cr-release assay. In this report, we present further investigations into this phenomenon. These alloactivated killer cells (A-AK cells) lysed autologous and allogeneic tumors and allogeneic but not autologous PBL. Furthermore, cold target inhibition studies demonstrated that autologous and allogeneic tumors were lysed by the same effector cells. Multiple metastases from the same patient were equivalently lysed by these A-AK cells. The presence of adherent cells and proliferation of the precursors were necessary to generate A-AK cells, although the effector cell itself was radioresistant and nonadherent. The effects of allosensitization were enhanced by the addition of lectin-free interleukin-2 preparations to the in vitro culture by partial depletion of adherent cells prior to sensitization. The A-AK effector cell was OKT3+, OKT8+, OKT4–, OKM1– and could be generated by just 3 days of allosensitization. The precursors for A-AK cells could be separated from NK cells on percoll gradients and lysis could be generated from thoracic duct lymphocytes, a population devoid of NK cells. The phenotype of the majority of the precursor cells was OKT3+, OKT4–. These allocatived PBL could be expanded in crude or lectin-free interleukin-2 without loss of cytotoxicity for fresh autologous tumor cells. Activated T cells represent a population of non-NK cells with broad lytic specificity for fresh tumor cells. Such cells may be of value in the adoptive immunotherapy of human solid tumors and may play a role in immune surveillance. 相似文献
97.
Inga M. Höben Rim Hjeij Heike Olbrich Gerard W. Dougherty Tabea Nöthe-Menchen Isabella Aprea Diana Frank Petra Pennekamp Bernd Dworniczak Julia Wallmeier Johanna Raidt Kim G. Nielsen Maria C. Philipsen Francesca Santamaria Laura Venditto Israel Amirav Huda Mussaffi Freerk Prenzel Heymut Omran 《American journal of human genetics》2018,102(5):973-984
98.
Sparsha Pallen Yuthika Shetty Subir Das Joel Markus Vaz Nirmal Mazumder 《Biophysical reviews》2021,13(6):1199
Understanding the mechanism of the brain via optical microscopy is one of the challenges in neuroimaging, considering the complex structures. Advanced neuroimaging techniques provide a more comprehensive insight into patho-mechanisms of brain disorders, which is useful in the early diagnosis of the pathological and physiological changes associated with various neurodegenerative diseases. Recent advances in optical microscopy techniques have evolved powerful tools to overcome scattering of light and provide improved in vivo neuroimaging with sub-cellular resolution, endogenous contrast specificity, pinhole less optical sectioning capability, high penetration depth, and so on. The following article reviews the developments in various optical imaging techniques including two-photon and three-photon fluorescence, second-harmonic generation, third-harmonic generation, coherent anti-Stokes Raman scattering, and stimulated Raman scattering in neuroimaging. We have outlined the potentials and drawbacks of these techniques and their possible applications in the investigation of neurodegenerative diseases. 相似文献
99.
Length‐weight relationships of Badis dibruensis Geetakumari and Vishwanath, 2010 (Badidae) and Lepidocephalichthys arunachalensis (Datta and Barman, 1984) (Cobitidae) from Subansiri River (Brahmaputra basin), Northeast India 下载免费PDF全文
H. Choudhury S. Mili S. Basumatary A. Mazumder D. Sarma 《Zeitschrift fur angewandte Ichthyologie》2017,33(6):1294-1295
Length–weight relationships (LWRs) for Badis dibruensis and Lepidocephalichthys arunachalensis, collected from the lower Subansiri River (Brahmaputra basin) in Assam, India from March 2016 to April 2017 using fishing gears namely cast nets (2.5 m, 1 m; 10–15 mm mesh size) and gillnets (30 × 0.9 m; 5–10 mm mesh size), are presented based on seasonal collections. The b values in the LWRs were determined as 2.56 for B. dibruensis and 3.28 for L. arunachalensis. 相似文献
100.
Alex G. Lee Megan Hagenauer Devin Absher Kathleen E. Morrison Tracy L. Bale Richard M. Myers Stanley J. Watson Huda Akil Alan F. Schatzberg David M. Lyons 《Biology of sex differences》2017,8(1):36