全文获取类型
收费全文 | 2294篇 |
免费 | 142篇 |
国内免费 | 5篇 |
专业分类
2441篇 |
出版年
2024年 | 8篇 |
2023年 | 52篇 |
2022年 | 101篇 |
2021年 | 161篇 |
2020年 | 168篇 |
2019年 | 266篇 |
2018年 | 167篇 |
2017年 | 113篇 |
2016年 | 145篇 |
2015年 | 99篇 |
2014年 | 152篇 |
2013年 | 187篇 |
2012年 | 165篇 |
2011年 | 151篇 |
2010年 | 82篇 |
2009年 | 79篇 |
2008年 | 75篇 |
2007年 | 57篇 |
2006年 | 46篇 |
2005年 | 40篇 |
2004年 | 40篇 |
2003年 | 26篇 |
2002年 | 25篇 |
2001年 | 2篇 |
2000年 | 2篇 |
1999年 | 3篇 |
1998年 | 3篇 |
1997年 | 7篇 |
1996年 | 1篇 |
1995年 | 5篇 |
1994年 | 2篇 |
1992年 | 2篇 |
1988年 | 3篇 |
1985年 | 1篇 |
1983年 | 2篇 |
1982年 | 1篇 |
1949年 | 1篇 |
1938年 | 1篇 |
排序方式: 共有2441条查询结果,搜索用时 15 毫秒
51.
52.
Maryam?Pourabdollah Mohammad?Bahmanyar Eshetu?G.?Atenafu Donna?Reece Jian?Hou Hong?ChangEmail author 《Journal of hematology & oncology》2016,9(1):123
The aim of this study is to assess nucleoprotein expression of IKZF1/3 in patients with relapsed/refractory multiple myeloma (MM) who received lenalidomide-based therapy and correlated them with their clinical outcomes. A total of 50 patients diagnosed with MM were entered in the study with the median follow-up of 86.4 months. By immunohistochemistry (IHC), IKZF1 and IKZF3 were expressed in 72 and 58% of the cases, respectively. IKZF1 and IKZF3 expressions were associated with longer median progression free survival (P?=?0.0029 and P?<?0.0001) and overall survival (P?=?0.0014 and P?<?0.0001). IKZF3 expression also appears predicted a favorable response to the lenalidomide-based therapy. 相似文献
53.
Ali Behrad Vakylabad Mahin Schaffie Ali Naseri Mohammad Ranjbar Zahra Manafi 《Bioprocess and biosystems engineering》2016,39(7):1081-1104
In this investigation, copper was bioleached from a low-grade chalcopyrite ore using a chloride-containing lixiviant. In this regard, firstly, the composition of the bacterial culture media was designed to control the cost in commercial application. The bacterial culture used in this process was acclimated to the presence of chloride in the lixiviant. Practically speaking, the modified culture helped the bio-heap-leaching system operate in the chloridic media. Compared to the copper recovery from the low-grade chalcopyrite by bioleaching in the absence of chloride, bioleaching in the presence of chloride resulted in improved copper recovery. The composition of the lixiviant used in this study was a modification with respect to the basal salts in 9 K medium to optimize the leaching process. When leaching the ore in columns, 76.81 % Cu (based on solid residues of bioleaching operation) was recovered by staged leaching with lixiviant containing 34.22 mM NaCl. The quantitative findings were supported by SEM/EDS observations, X-ray elemental mapping, and mineralogical analysis of the ore before and after leaching. Finally, Adaptive neuro-fuzzy inference system (ANFIS) was used to simulate the operational parameters affecting the bioleaching operation in chloride–sulfate system. 相似文献
54.
Seyedeh Maryam Banihashemian Vengadesh Periasamy Goh Boon Tong Saadah Abdul Rahman 《PloS one》2016,11(3)
Studying the effect of a magnetic field on oligonucleotide DNA can provide a novel DNA manipulation technique for potential application in bioengineering and medicine. In this work, the optical and electrochemical response of a 100 bases oligonucleotides DNA, cytosine-guanine (CG100), is investigated via exposure to different magnetic fields (250, 500, 750, and 1000 mT). As a result of the optical response of CG100 to the magnetic field, the ultra-violet-visible spectrum indicated a slight variation in the band gap of CG100 of about 0.3 eV. Raman spectroscopy showed a significant deviation in hydrogen and phosphate bonds’ vibration after exposure to the magnetic field. Oligonucleotide DNA mobility was investigated in the external electric field using the gel electrophoresis technique, which revealed a small decrease in the migration of CG100 after exposure to the magnetic field. 相似文献
55.
56.
Maryam Heidari Kharaji Delaram Doroud Tahereh Taheri Sima Rafati 《AAPS PharmSciTech》2016,17(5):1110-1119
Leishmaniasis is a worldwide disease that leads to high mortality and morbidity in human populations. Today, leishmaniasis is managed via drug therapy. The drugs that are already in clinical use are limited to a number of toxic chemical compounds and their parasite drug resistance is increasing. It is therefore essential, in order to circumvent the current difficulties, to design a new anti-leishmanial drug treatment strategy. Besides producing new, active anti-leishmanial entities, another promising strategy could be developing novel delivery systems and formulations of the existing pharmaceutical ingredients to improve drug efficacy. In the present study, paromomycin sulfate (PM), as one of the promising anti-leishmanial drugs, was formulated in solid lipid nanoparticles (SLN), and its in vitro efficacy was investigated against different strains of Leishmania using a MTT test, Parasite-Rescue-Transformation-Assay, SYTO Green staining, and fluorescent microscope imaging. The results show that PM-loaded SLN is significantly more effective than PM in inhibiting parasite propagation (P?<?0.05) and that cytotoxicity of PM-SLN formulations is size dependent. According to our results, delivery of the drugs to the macrophages via nanoparticle utilization seems to be an accessible and practical approach. 相似文献
57.
Reactivation of mutant p53: Constraints on mechanism highlighted by principal component analysis of the DNA binding domain 下载免费PDF全文
Zahra Ouaray Karim M. ElSawy David P. Lane Jonathan W. Essex Chandra Verma 《Proteins》2016,84(10):1443-1461
Most p53 mutations associated with cancer are located in its DNA binding domain (DBD). Many structures (X‐ray and NMR) of this domain are available in the protein data bank (PDB) and a vast conformational heterogeneity characterizes the various free and complexed states. The major difference between the apo and the holo‐complexed states appears to lie in the L1 loop. In particular, the conformations of this loop appear to depend intimately on the sequence of DNA to which it binds. This conclusion builds upon recent observations that implicate the tetramerization and the C‐terminal domains (respectively TD and Cter) in DNA binding specificity. Detailed PCA analysis of the most recent collection of DBD structures from the PDB have been carried out. In contrast to recommendations that small molecules/drugs stabilize the flexible L1 loop to rescue mutant p53, our study highlights a need to retain the flexibility of the p53 DNA binding surface (DBS). It is the adaptability of this region that enables p53 to engage in the diverse interactions responsible for its functionality. Proteins 2016; 84:1443–1461. © 2016 Wiley Periodicals, Inc. 相似文献
58.
59.
Bevacizumab Antibody Affinity Maturation to Improve Ovarian Cancer Immunotherapy: In Silico Approach
Eyvazi Shirin Payandeh Zahra Khalili Saeed Sefid Fatemeh Ouladsahebmadarek Elaheh 《International journal of peptide research and therapeutics》2019,25(4):1417-1430
International Journal of Peptide Research and Therapeutics - Ovarian cancer is one of the most lethal gynecologic cancers. The high mortality rate is due to lack of early symptoms and developing... 相似文献
60.
Zahra Rahmani Chang‐Jun Kim Mostafa Ghafouri Moghaddam Ehsan Rakhshani 《Entomological Research》2019,49(9):409-415
Occurrence of the family Ismaridae Thomson is recorded for the first time from Iran, represented by a single species, Ismarus rugulosus Förster, 1850. A series of diagnostic characters and morphometric ratios for this species is presented, as well as a distribution map throughout the Holarctic region. 相似文献