全文获取类型
收费全文 | 6536篇 |
免费 | 556篇 |
国内免费 | 3篇 |
专业分类
7095篇 |
出版年
2023年 | 49篇 |
2022年 | 124篇 |
2021年 | 231篇 |
2020年 | 105篇 |
2019年 | 139篇 |
2018年 | 163篇 |
2017年 | 119篇 |
2016年 | 236篇 |
2015年 | 380篇 |
2014年 | 357篇 |
2013年 | 442篇 |
2012年 | 600篇 |
2011年 | 536篇 |
2010年 | 338篇 |
2009年 | 260篇 |
2008年 | 375篇 |
2007年 | 397篇 |
2006年 | 349篇 |
2005年 | 319篇 |
2004年 | 309篇 |
2003年 | 260篇 |
2002年 | 234篇 |
2001年 | 56篇 |
2000年 | 51篇 |
1999年 | 46篇 |
1998年 | 65篇 |
1997年 | 31篇 |
1996年 | 29篇 |
1995年 | 27篇 |
1994年 | 32篇 |
1993年 | 33篇 |
1992年 | 24篇 |
1991年 | 29篇 |
1990年 | 24篇 |
1989年 | 23篇 |
1988年 | 16篇 |
1987年 | 14篇 |
1986年 | 12篇 |
1985年 | 18篇 |
1984年 | 22篇 |
1983年 | 20篇 |
1982年 | 18篇 |
1981年 | 11篇 |
1980年 | 15篇 |
1978年 | 18篇 |
1977年 | 12篇 |
1976年 | 9篇 |
1975年 | 8篇 |
1972年 | 7篇 |
1971年 | 12篇 |
排序方式: 共有7095条查询结果,搜索用时 0 毫秒
21.
22.
Hongsheng Liu Long Yu George Simon Katherine Dean Ling Chen 《Carbohydrate polymers》2009,77(3):662-669
Corn starches with different amylose/amylopectin ratios (waxy 0/100, normal corn 23/77, Gelose 50 50/50, Gelose 80 80/20) were annealed at below their gelatinization temperatures in excess water. The effects of annealing on the gelatinization and microstructures of the starches were studied using DSC, XRD and a microscope equipped with both normal and polarized light. In addition, a high-pressure DSC pan was used to study the effects of high-temperature annealing on the multiphase transitions of starches with different water contents. The granular size of the starches increased after the annealing process, but the size variation rates were different, with higher amylopectin contents resulting in a higher diameter growth rates and final accretion ratios. DSC results showed that annealing increased the gelatinization enthalpy of the amylose-rich starches. The increased enthalpy was mainly attributed to endotherm G – there were no significant changes to endotherms M1, M2 or Z – indicating that annealing mainly affected the helical length of shorter or sub-optional amylopectins, in particular the amylopectin in amylose-rich starches. The XRD traces of all starches after annealing remained unchanged. 相似文献
23.
24.
25.
Kathryn Davidson Paul Grevitt Maria F. Contreras-Gerenas Katherine S. Bridge Miguel Hermida Kunal M. Shah Faraz K. Mardakheh Mark Stubbs Rosemary Burke Pedro Casado Pedro R. Cutillas Sarah A. Martin Tyson V. Sharp 《Cell death & disease》2021,12(11)
An early event in lung oncogenesis is loss of the tumour suppressor gene LIMD1 (LIM domains containing 1); this encodes a scaffold protein, which suppresses tumorigenesis via a number of different mechanisms. Approximately 45% of non-small cell lung cancers (NSCLC) are deficient in LIMD1, yet this subtype of NSCLC has been overlooked in preclinical and clinical investigations. Defining therapeutic targets in these LIMD1 loss-of-function patients is difficult due to a lack of ‘druggable’ targets, thus alternative approaches are required. To this end, we performed the first drug repurposing screen to identify compounds that confer synthetic lethality with LIMD1 loss in NSCLC cells. PF-477736 was shown to selectively target LIMD1-deficient cells in vitro through inhibition of multiple kinases, inducing cell death via apoptosis. Furthermore, PF-477736 was effective in treating LIMD1−/− tumours in subcutaneous xenograft models, with no significant effect in LIMD1+/+ cells. We have identified a novel drug tool with significant preclinical characterisation that serves as an excellent candidate to explore and define LIMD1-deficient cancers as a new therapeutic subgroup of critical unmet need.Subject terms: Targeted therapies, Non-small-cell lung cancer 相似文献
26.
27.
Ramazan Ulus İbrahim Yeşildağ Muhammet Tanç Metin Bülbül Muharrem Kaya Claudiu T. Supuran 《Bioorganic & medicinal chemistry》2013,21(18):5799-5805
4-Amino-N-(4-sulfamoylphenyl)benzamide was synthesized by reduction of 4-nitro-N-(4-sulfamoylphenyl)benzamide and used to synthesize novel acridine sulfonamide compounds, by a coupling reaction with cyclic-1,3-diketones and aromatic aldehydes. The new compounds were investigated as inhibitors of the metalloenzyme carbonic anhydrase (CA, EC 4.2.1.1), and more precisely the cytosolic isoforms hCA I, II and VII. hCA I was inhibited in the micromolar range by the new compounds (KIs of 0.16–9.64 μM) whereas hCA II and VII showed higher affinity for these compounds, with KIs in the range of 15–96 nM for hCA II, and of 4–498 nM for hCA VII. The structure–activity relationships for the inhibition of these isoforms with the acridine–sulfonamides reported here were also elucidated. 相似文献
28.
Cryopreserved human haematopoietic stem cells retain engraftment potential after extended (5-14 years) cryostorage 总被引:3,自引:0,他引:3
Harvesting of stem cells during the early phases of treatment with no immediate intention to perform a stem cell transplant is becoming an increasingly common practice. Such "insurance" harvests are often stored for many years before being needed for transplant in a subsequent relapse. The effect of long-term cryostorage (5-14 years) on the viability and functional capacity of haematopoietic stem cells (HSCs) was investigated in 40 bone marrow and peripheral blood harvests using standard in vitro methods, the colony forming unit-granulocyte/macrophage (CFU-GM) assay and a single platform viable CD34(+) cell absolute count by flow cytometry. Forty percent of harvests had CD34(+) HSC counts of at least 0.7 x 10(6)/kg bodyweight and 85% had CFU-GM counts of at least 1.0 x 10(5)/kg bodyweight, these values representing our institutional minimum requirements for safe transplantation. Based on these results, it appears that HSC collections can remain adequate for safe transplantation after up to 14 years of cryostorage. However, as deterioration of HSC quality and viability may occur, some precautions may be warranted, namely harvesting higher than normal numbers of HSCs in collections intended for long-term storage and repeating in vitro assays on harvests after long-term storage prior to transplantation. 相似文献
29.
30.