全文获取类型
收费全文 | 591篇 |
免费 | 47篇 |
出版年
2022年 | 4篇 |
2021年 | 11篇 |
2020年 | 8篇 |
2019年 | 17篇 |
2018年 | 9篇 |
2017年 | 7篇 |
2016年 | 17篇 |
2015年 | 21篇 |
2014年 | 25篇 |
2013年 | 31篇 |
2012年 | 49篇 |
2011年 | 58篇 |
2010年 | 26篇 |
2009年 | 22篇 |
2008年 | 41篇 |
2007年 | 52篇 |
2006年 | 35篇 |
2005年 | 32篇 |
2004年 | 33篇 |
2003年 | 50篇 |
2002年 | 34篇 |
2001年 | 5篇 |
2000年 | 6篇 |
1999年 | 8篇 |
1998年 | 7篇 |
1997年 | 4篇 |
1996年 | 7篇 |
1995年 | 2篇 |
1993年 | 3篇 |
1992年 | 5篇 |
1990年 | 1篇 |
1989年 | 2篇 |
1988年 | 1篇 |
1986年 | 3篇 |
1982年 | 1篇 |
1975年 | 1篇 |
排序方式: 共有638条查询结果,搜索用时 15 毫秒
1.
2.
Antibodies to human amyloid precursor protein (APP695) and beta‐amyloid peptide (Aβ1‐42) were used to determine timing of amyloidosis in the brain of kokanee salmon (Oncorhynchus nerka kennerlyi) in one of four reproductive stages: immature (IM), maturing (MA), sexually mature (SM), and spawning (SP), representing a range of aging from somatically mature but sexually immature to spawning and somatic senescence. In IM fish, immunoreactive (ir) intracellular APP occurred in 18 of 23 brain regions. During sexual maturation and aging, the number of neurons expressing APP increased in 11 of these APP‐ir regions. Aβ‐ir was absent in IM fish, present in seven regions in MA fish, moderately abundant in 15 regions in SM fish, and was most abundant in all brain regions of SP fish exhibiting Aβ‐ir. Intracellular APP‐ir was observed in brain regions involved in sensory integration, olfaction, vision, stress responses, reproduction, and coordination. Intra‐ and extracellular Aβ1‐42 immunoreactivity (Aβ‐ir) was present in all APP‐ir regions except the nucleus lateralis tuberis (hypothalamus) and Purkinje cells (cerebellum). APP‐ir and Aβ deposition increase during aging. APP‐ir is present in IM fish; Aβ‐ir usually appears first in MA or SM fish and increases in SM fish as does APP‐ir. Extracellular Aβ deposition dramatically increases between SM and SP stages (1–2 weeks) in all fish, indicating an extremely rapid and synchronized process. Rapid senescence observed in pacific salmon could make them a useful model to investigate timing of amyloidosis and neurodegeneration during brain aging. © 2002 Wiley Periodicals, Inc. J Neurobiol 53: 11–20, 2002 相似文献
3.
Charles R. Ill Tammy Brehm Bjorn K. Lydersen Rachel Hernandez Karen G. Burnett 《In vitro cellular & developmental biology. Plant》1988,24(5):413-419
Summary Studies with Human x Human (HxH), Human x Mouse (HxM), and Mouse x Mouse (MxM) hybridomas have enabled us to define specific
factors that affect hybridoma growth in a species-specific manner. Three transferrins and three lipophilic iron chelates have
been tested for their ability to support hybridoma proliferation and antibody production. The results of these studies demonstrate
that HxH hybridomas do not respond to bovine transferrin a+ concentrations up to 100 μg/ml and are approximately 100-fold less responsive to mouse transferrin than to human transferrin.
HxM and MxM hybridomas respond equally to human or mouse transferrin but are 100-fold less sensitive to bovine transferrin.
An antibody to the human transferrin receptor inhibited the growth-promoting activity of human or mouse transferrin on HxH
hybridomas but was ineffective on HxM hybridomas. This semonstrated the functionality of the human transferrin receptor in
HxH hybridomas and that human, mouse, and bovine transferrin were interacting through the mouse transferrin receptor in HxM
hybridomas. HxH and HxM hybridomas respond similarly to three different iron chelates exhibiting 80 to 110% of the growth
response to human transferrin. MxM hybridomas fail to respond to the iron chelates at similar concentrations, suggesting that
the human genome present in the other hybridoma species confers a unique ability for utilizing iron when delivered in this
form. 相似文献
4.
Interstrain Variation in Amylase Gene Copy Number and mRNA Abundance in Three Mouse Tissues 总被引:2,自引:0,他引:2
下载免费PDF全文
![点击此处可从《Genetics》网站下载免费的PDF全文](/ch/ext_images/free.gif)
Miriam H. Meisler Tammy K. Antonucci Laurelee O. Treisman Deborah L. Gumucio Linda C. Samuelson 《Genetics》1986,113(3):713-722
Amylase expression in strain YBR differs in several respects from the standard mouse phenotype. The synthesis of salivary amylase is elevated twofold in YBR mice and the synthesis of pancreatic amylase is reduced to one-half the normal rate. We have compared the concentrations of amylase mRNA in the parotid, liver and pancreas of YBR mice with those in strains A/J and C3H. We observed differences in amylase mRNA abundance which can account for the levels of amylase protein synthesis in the parotid and pancreas of these strains. Unexpectedly, the concentration of amylase mRNA in the liver of YBR mice was also higher than in the other strains. Since liver amylase is transcribed from the same gene as parotid amylase, duplication of the Amy-1 locus could account for the elevated mRNA concentration in both tissues. Quantitative analysis of genomic DNA by Southern blotting provided direct evidence for duplication of Amy-1 in strain YBR. 相似文献
5.
6.
7.
8.
Assessment of human adenovirus removal by qPCR in an advanced water reclamation plant in Georgia,USA
P. Liu O. Herzegh M. Fernandez S. Hooper W. Shu J. Sobolik R. Porter N. Spivey C. Moe 《Journal of applied microbiology》2013,115(1):310-318
Aims
To assess human adenoviruses (HAdVs) removal in an advanced wastewater treatment facility and compare two parallel tertiary treatment methods for the removal of HAdVs.Methods and Results
Tangential flow ultrafiltration was used to concentrate the water samples, and HAdVs were precipitated by polyethylene glycol. HAdVs were detected only by TaqMan real‐time PCR, and HAdV genotype was determined by DNA sequence. HAdVs were detected in 100% of primary clarification influent, secondary clarification effluent and granular media (GM) filtration effluent samples but only in 31·2% of membrane filtration (MF) effluent and 41·7% of final effluent (FE) samples, respectively. The average HAdVs loads were significantly reduced along the treatments but HAdVs were still present in FE. Comparison of two parallel treatments (GM vs MF) showed that MF was technically superior to GM for the removal of HAdVs.Conclusions
These findings indicate that adenoviruses are not completely removed by treatment processes. MF is a better treatment for removal of adenoviruses than GM filtration. Because only qPCR was used, the results only indicate the removal of adenovirus DNA and not the infectivity of viruses.Significance and Impact of the Study
Presence of HAdVs in FE by qPCR suggests a potential public health risk from exposure to the treated wastewater and using the FE for recreational or water reuse purposes should be cautious. 相似文献9.
Gudka Mishal Obura David Mbugua James Ahamada Said Kloiber Ulli Holter Tammy 《Coral reefs (Online)》2020,39(1):1-11
Coral Reefs - Climate change, coupled with an El Niño, caused a devastating bleaching event in the Western Indian Ocean (WIO) in 1998. Similar extreme conditions at the end of 2015 meant that... 相似文献
10.
Robert H. C. Chen Sabine Wislet-Gendebien Filsy Samuel Naomi P. Visanji Gang Zhang Diana Marsilio Tammy Langman Paul E. Fraser Anurag Tandon 《The Journal of biological chemistry》2013,288(11):7438-7449
α-Synuclein is an abundant presynaptic protein and a primary component of Lewy bodies in Parkinson disease. Although its pathogenic role remains unclear, in healthy nerve terminals α-synuclein undergoes a cycle of membrane binding and dissociation. An α-synuclein binding assay was used to screen for vesicle proteins involved in α-synuclein membrane interactions and showed that antibodies directed to the Ras-related GTPase Rab3a and its chaperone RabGDI abrogated α-synuclein membrane binding. Biochemical analyses, including density gradient sedimentation and co-immunoprecipitation, suggested that α-synuclein interacts with membrane-associated GTP-bound Rab3a but not to cytosolic GDP-Rab3a. Accumulation of membrane-bound α-synuclein was induced by the expression of a GTPase-deficient Rab3a mutant, by a dominant-negative GDP dissociation inhibitor mutant unable to recycle Rab3a off membranes, and by Hsp90 inhibitors, radicicol and geldanamycin, which are known to inhibit Rab3a dissociation from membranes. Thus, all treatments that inhibited Rab3a recycling also increased α-synuclein sequestration on intracellular membranes. Our results suggest that membrane-bound GTP-Rab3a stabilizes α-synuclein on synaptic vesicles and that the GDP dissociation inhibitor·Hsp90 complex that controls Rab3a membrane dissociation also regulates α-synuclein dissociation during synaptic activity. 相似文献