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991.
NK cells play important roles in innate immunity against tumors and infections of the host. Studies show that CD107a (LAMP-1) may be a marker for degranulation of NK and activated CD8+ T cells. In our study, the relationship between the expression of CD107a, cytokine secretion and cytotoxic activity in CD56+ NK, CD8+ T cells and lymphocytes has been determined after various stimuli. Effector cells from PBMCs of healthy subjects were isolated and K562 cell line was used as target of cytotoxicity. IL-2 stimulation resulted in a significant increase of CD107a expression in CD56+ NK, CD8+ T cells and lymphocytes. Increased expression of CD107a after IL-2 stimulation of NK cells was parallel to the increase of cytotoxicity. Our results suggest that CD107a expression may be a sensitive marker for the cytotoxic activity determination. 相似文献
992.
Xiumin Lu Nan Su Jing Yang Can Li Qifen He Yue Shen Lin Chen 《Biochemical and biophysical research communications》2009,390(3):494-3094
To elucidate the direct role and mechanism of FGFR1 signaling in the differentiation and activation of osteoclasts, we conditionally inactivated FGFR1 in bone marrow monocytes and mature osteoclasts of mice. Mice deficient in FGFR1 (Fgfr1−/−) exhibited misregulated bone remodeling with reduced osteoclast number and impaired osteoclast function. In vitro assay demonstrated that the number of tartrate-resistant acid phosphatase (TRAP) positive osteoclasts derived from bone marrow monocytes of Fgfr1−/− mice was significantly diminished. The bone resorption activity of mature osteoclasts derived from Fgfr1−/− mice was also suppressed. Further analysis showed that the osteoclasts with FGFR1 deficiency exhibited downregulated expression of genes related to osteoclastic activity including TRAP and MMP-9. The phosphorylation of Erk1/2 mitogen-activated protein (MAP) kinase was also decreased. Our results suggest that FGFR1 is indispensable for complete differentiation and activation of osteoclasts in mice. 相似文献
993.
994.
Açikgoz S Harma M Harma M Mungan G Can M Demirtas S 《Biological trace element research》2006,113(1):1-8
Preeclampsia is a syndrome of unknown etiopathogenesis. Recent studies carried out on preeclampsia have focused on the increase
in free radicals in the feto-placental unit with poor perfusion. It is believed that the renin-angiotensin system (RAS) has
a role in the poor perfusion of the placenta. It is uncertain whether there is a pre-existing impairment in RAS in pre-eclamptic
pregnant women or not. In the present study, we measured angiotensin-converting enzyme (ACE), malonaldehyde (MDA), zinc, and
copper levels in the placental tissue of 16 pre-eclamptic pregnant women and compared them with those in 20 healthy pregnant
women.
Whereas ACE activity and MDA were found to be high in the placentas of pre-eclamptic patients, zinc and copper levels were
low and there was a negative correlation between ACE activity and zinc concentration. These findings suggest that high ACE
activity might play a role in the increase in tissue hypoxia and consequent lipid peroxidation through vasoconstriction; zinc
deficiency in the placental tissue might cause insufficiency of superoxide dismutase, an antioxidant enzyme. Furthermore,
deficiency in placental zinc also plays a role in the biosynthesis of connective tissue, maintaining its integrity, which
might have an impact on the structure of the spiral arteries 相似文献
995.
Background
Prospective population-based neuropathological studies have a special place in dementia research which is under emphasised. 相似文献996.
为了探讨在人永生化支气管上皮细胞BEP2D细胞中,Smad4分子对 ERK/MAPK通路的作用,我们用RNA干扰的方法分别设计了两对Smad4 siRNA,并使BEP2D细胞中Smad4靶向沉默,用Western印迹分析了细胞内ERK激酶和MEK激酶磷酸化水平的变化.结果发现,当Smad4表达沉默后,ERK激酶磷酸化水平未变,MEK激酶磷酸化水平有所降低;再加TGF-β1诱导后ERK激酶和MEK激酶磷酸化水平均显著降低至基础水平以下.结果表明在BEP2D细胞中,Smad4的缺失抑制TGF-β1对ERK/MAPK通路的活化,故提出TGF β活化ERK/MAPK通路需要Smad4存在的假设. 相似文献
997.
目的:探讨人永生化BEP2D细胞中TGF-β活化ERK/MAPK通路的机制。方法:用RNA干扰的方法设计siRNAs使人永生化BEP2D细胞中TβRⅡ、Smad7基因沉默,用Westernblot分析TGF-β1诱导的ERK激酶磷酸化的变化。结果:当Smad7表达沉默后,TGF-β1诱导的ERK激酶磷酸化水平显著降低;当TβRⅡ和Smad7表达同时发生沉默后,细胞内TGF-β1诱导的ERK激酶磷酸化水平进一步降低到基础水平以下。结论:TGF-β1以受体和Smad7依赖的方式活化ERK/MAPK通路。 相似文献
998.
Ayse Gul Ince Mehmet Karaca A. Naci Onus 《Molecular breeding : new strategies in plant improvement》2010,25(3):491-499
Microsatellites found in expressed sequence tags (ESTs) have several advantages in comparison to conventional microsatellites
developed from genomic DNA. Advantages of EST-microsatellites include better transferability between the species and lower
development cost of primer pairs. However, in many cases the amplified products of genomic DNA are larger than their expected
sizes based on ESTs and these markers have low level of polymorphism. In the present study we report on a new approach as
a modest modification of the cleavage amplified polymorphic sequence (CAPS) called CAPS-microsatellites. Using a total of
20 EST-microsatellite primer pairs on four Capsicum species and two Gossypium species we observed that all 20 monomorphic EST-microsatellites could be converted into polymorphic markers among the species
used. Further analyses using a total of 37 F2 individuals obtained from two Capsicum annuum L. lines indicated that CAPS-microsatellite markers usually segregated as co-dominant fashions, discriminating the homozygous
from heterozygous genotypes and could be used in genetic analyses of plant species. 相似文献
999.
Nan Su Xiaoling Xu Cuiling Li Qifen He Ling Zhao Can Li Siyu Chen Fengtao Luo Lingxian Yi Xiaolan Du Haiyang Huang Chuxia Deng Lin Chen 《International journal of biological sciences》2010,6(4):327-332
Fibroblast growth factor receptor 3 (FGFR3), highly conserved in both humans and murine, is one of key tyrosine kinase receptors for FGF. FGFR3 is expressed in different tissues, including cartilage, brain, kidney, and intestine at different development stages. Conventional knockout of Fgfr3 alleles leads to short life span, and overgrowth of bone. In clinic, human FGFR3 mutations are responsible for three different types of chondrodysplasia syndromes including achondroplasia (ACH), hypochondroplasia (HCH) and thanatophoric dysplasia (TD). For better understanding of the roles of FGFR3 in different tissues at different stages of development and in pathological conditions, we generated Fgfr3 conditional knockout mice in which loxp sites flank exons 9-10 in the Fgfr3 allele. We also demonstrated that Cre-mediated recombination using Col2a1-Cre, a Cre line expressed in chondrocyte during bone development, results in specific deletion of the gene in tissues containing cartilage. This animal model will be useful to study distinct roles of FGFR3 in different tissues at different ages. 相似文献
1000.
Short term effects of a low-carbohydrate diet in overweight and obese subjects with low HDL-C levels