全文获取类型
收费全文 | 314篇 |
免费 | 16篇 |
出版年
2023年 | 6篇 |
2022年 | 4篇 |
2021年 | 18篇 |
2020年 | 8篇 |
2019年 | 7篇 |
2018年 | 9篇 |
2017年 | 6篇 |
2016年 | 10篇 |
2015年 | 17篇 |
2014年 | 18篇 |
2013年 | 22篇 |
2012年 | 24篇 |
2011年 | 30篇 |
2010年 | 20篇 |
2009年 | 10篇 |
2008年 | 18篇 |
2007年 | 18篇 |
2006年 | 20篇 |
2005年 | 22篇 |
2004年 | 11篇 |
2003年 | 12篇 |
2002年 | 3篇 |
2001年 | 1篇 |
2000年 | 1篇 |
1998年 | 2篇 |
1997年 | 2篇 |
1994年 | 1篇 |
1993年 | 3篇 |
1991年 | 3篇 |
1990年 | 2篇 |
1987年 | 1篇 |
1986年 | 1篇 |
排序方式: 共有330条查询结果,搜索用时 78 毫秒
91.
Barli O Elmali D Midilli R Aydintan E Ustün S Sagsöz A Ozgen S Gedik T 《Collegium antropologicum》2005,29(1):45-51
This paper presents the results of an anthropometrical survey conducted on male and female children aged 3, 4 and 5 years in Turkey. A set of 18 body dimensions was taken from 154 males and 132 females. It is considered that the 18 parameters are necessary for the design of school furniture, fittings and equipment in order to minimize musculoskeletal, visual and circulatory problems resulting from badly designed elements. This study identified significant gender differences in a set of 18 anthropometrical measures in this subject group. 相似文献
92.
Alemdar A Iridag Y Kazanci M 《International journal of biological macromolecules》2005,35(3-4):151-153
Keratin is abundantly present in nature and the major component of hair, wool, feather, nail and horns. Dissolution of keratin is often required when non-textile applications are demanded. However, the low solubility of keratin in water is the major problem. It becomes unstable and precipitated when stored for a long time. Therefore, it is necessary to find a good solvent that provides high stability and easy processibility. In this research, we used formic acid and dimethylformamide (DMF) to dissolve regenerated keratin protein films. It is shown that formic acid is a good solvent for regenerated keratin proteins for the purpose of storage. Transparent and stable regenerated keratin solution is obtained in formic acid. 相似文献
93.
Expression of glucose transporter 1 confers susceptibility to human T-cell leukemia virus envelope-mediated fusion 下载免费PDF全文
Human T-cell leukemia virus type 1 (HTLV-1) was the first human retrovirus identified and causes both adult T-cell leukemia/lymphoma and tropical spastic paraparesis/HTLV-1-associated myelopathy, among other disorders. In vitro, HTLV-1 has an extremely broad host cell tropism in that it is capable of infecting most mammalian cell types, although at the same time viral titers remain relatively low. Despite years of study, only recently has a bona fide candidate cellular receptor, glucose transporter 1 (glut-1), been identified. Although glut-1 was shown to bind specifically to the ectodomain of HTLV-1 and HTLV-2 envelope glycoproteins, which was reversible with small interfering RNA directed against glut-1, cellular susceptibility to HTLV upon expression of glut-1 was not established. Here we show that expression of glut-1 in relatively resistant MDBK cells conferred increased susceptibility to both HTLV-1- and HTLV-2-pseudotyped particles. glut-1 also markedly increased syncytium formation in MDBK cells after exposure to HTLV-1. Another assay also demonstrated HTLV-1 envelope-cell fusion in the presence of glut-1. Taken together, these results provide additional evidence that glut-1 is a receptor for HTLV. 相似文献
94.
The genotoxic risk of underground coal miners from Turkey 总被引:4,自引:0,他引:4
A cytogenetic monitoring study was carried out on a group of workers from a bituminous coal mine in Zonguldak province of Turkey, to investigate the genotoxic risk of occupational exposure to coal mine dust. Cytogenetic analysis, namely sister chromatid exchanges (SCEs), chromosomal aberrations (CAs) and micronucleus (MN) tests were performed on a strictly selected group of 39 workers and compared to 34 controls matched for gender, age, and habit. Smoking and age were considered as modulating factors. Both SCE and CA frequencies in coal miners appeared significantly higher than in controls. Similarly, there was a significant increase in the frequency of total micronuclei in exposed group as compared to control group. The effect of smoking on the level of SCE and MN was significant in the control group. A positive correlation between the age and the level of SCE was also found in controls. The frequencies of both SCE and CA were significantly enhanced with the years of exposure. The results of this study demonstrated that occupational exposure to coal mine dust leads to a significant induction of cytogenetic damage in peripheral lymphocytes of workers engaged in underground coal mining. 相似文献
95.
96.
DeGiorgis JA Jaffe H Moreira JE Carlotti CG Leite JP Pant HC Dosemeci A 《Journal of proteome research》2005,4(2):306-315
Protein phosphorylation is a crucial post-translational modification mechanism in the regulation of synaptic organization and function. Here, we analyzed synaptosome fractions from human cerebral cortex obtained during therapeutic surgery. To minimize changes in the phosphorylation state of proteins, the tissue was homogenized within two minutes of excision. Synaptosomal proteins were digested with trypsin and phosphopeptides were isolated by immobilized metal affinity chromatography and analyzed by liquid chromatography and tandem mass spectrometry. The method allowed the detection of residues on synaptic proteins that were presumably phosphorylated in the intact cell, including synapsin 1, syntaxin 1, and SNIP, PSD-93, NCAM, GABA-B receptor, chaperone molecules, and protein kinases. Some of the residues identified are the same or homologous to sites that had been previously described to be phosphorylated in mammals whereas others appear to be novel sites which, to our knowledge, have not been reported previously. The study shows that new phosphoproteomic strategies can be used to analyze subcellular fractions from small amounts of tissue for the identification of phosphorylated residues for research and potentially for diagnostic purposes. 相似文献
97.
Ayse KAPLAN 《植物学报(英文版)》2004,46(6):668-674
The variation in airborne pollen concentration of the Zonguldak region, Turkey was studied for two consecutive years 2001-2002 using a Durham sampler. During this period, a total of 61 304 pollen grains belonging to 43 taxa were recorded. Of these 43 taxa, 26 belonged to arboreal and 17 to nonarboreal plants. The main pollen types were Pinaceae, Populus, Carpinus, Betula, Corylus, Fagus orientalis,Castanea sativa, Alnus glutinosa, Quercus, Cupressaceae, Chenopodiaceae and Gramineae, representing 96.7% of the pollen spectrum. Pollen concentration reached the highest level in March. 相似文献
98.
Fakhriddin Sarzhanov Funda Dogruman-Al Monica Santin Jenny G. Maloney Ayse Semra Gureser Djursun Karasartova Aysegul Taylan-Ozkan 《PLoS neglected tropical diseases》2021,15(10)
IntroductionThe clinical significance of Blastocystis sp. and Dientamoeba fragilis in patients with gastrointestinal symptoms is a controversial issue. Since the pathogenicity of these protists has not been fully elucidated, testing for these organisms is not routinely pursued by most laboratories and clinicians. Thus, the prevalence of these organisms and the subtypes of Blastocystis sp. in human patients in Turkey are not well characterized. This study aimed to determine the prevalence of Blastocystis sp. and D. fragilis in the diarrheic stool samples of immunodeficient and immunocompetent patients using conventional and molecular methods and to identify Blastocystis sp. subtypes using next generation sequencing.Material and methodsIndividual stool specimens were collected from 245 immunodeficient and 193 immunocompetent diarrheic patients between March 2017 and December 2019 at the Gazi University Training and Research Hospital in Ankara, Turkey. Samples were screened for Blastocystis sp. and D. fragilis by conventional and molecular methods. Molecular detection of both protists was achieved by separate qPCRs targeting a partial fragment of the SSU rRNA gene. Next generation sequencing was used to identify Blastocystis sp. subtypes.ResultsThe prevalence of Blastocystis sp. and D. fragilis was 16.7% and 11.9%, respectively as measured by qPCR. The prevalence of Blastocystis sp. and D. fragilis was lower in immunodeficient patients (12.7% and 10.6%, respectively) compared to immunocompetent patients (21.8% and 13.5%, respectively). Five Blastocystis sp. subtypes were identified and the following subtype distribution was observed: ST3 54.4% (n = 37), ST2 16.2% (n = 11), ST1 4.4% (n = 3), ST6 2.9% (n = 2), ST4 1.5% (n = 1), ST2/ST3 11.8% (n = 8) and ST1/ST3 8.8% (n = 6). There was no statistically significant difference in the distribution of Blastocystis sp. subtypes between immunocompetent and immunodeficient patients.Conclusion and recommendationOur findings demonstrated that Blastocystis sp. and D. fragilis are commonly present in immunocompetent and immunodeficient patients with diarrhea. This study is the first to use next generation sequencing to address the presence of Blastocystis sp. mixed subtypes and intra-subtype variability in clinical samples in Turkey. 相似文献
99.
Fugier C Klein AF Hammer C Vassilopoulos S Ivarsson Y Toussaint A Tosch V Vignaud A Ferry A Messaddeq N Kokunai Y Tsuburaya R de la Grange P Dembele D Francois V Precigout G Boulade-Ladame C Hummel MC Lopez de Munain A Sergeant N Laquerrière A Thibault C Deryckere F Auboeuf D Garcia L Zimmermann P Udd B Schoser B Takahashi MP Nishino I Bassez G Laporte J Furling D Charlet-Berguerand N 《Nature medicine》2011,17(6):720-725
Myotonic dystrophy is the most common muscular dystrophy in adults and the first recognized example of an RNA-mediated disease. Congenital myotonic dystrophy (CDM1) and myotonic dystrophy of type 1 (DM1) or of type 2 (DM2) are caused by the expression of mutant RNAs containing expanded CUG or CCUG repeats, respectively. These mutant RNAs sequester the splicing regulator Muscleblind-like-1 (MBNL1), resulting in specific misregulation of the alternative splicing of other pre-mRNAs. We found that alternative splicing of the bridging integrator-1 (BIN1) pre-mRNA is altered in skeletal muscle samples of people with CDM1, DM1 and DM2. BIN1 is involved in tubular invaginations of membranes and is required for the biogenesis of muscle T tubules, which are specialized skeletal muscle membrane structures essential for excitation-contraction coupling. Mutations in the BIN1 gene cause centronuclear myopathy, which shares some histopathological features with myotonic dystrophy. We found that MBNL1 binds the BIN1 pre-mRNA and regulates its alternative splicing. BIN1 missplicing results in expression of an inactive form of BIN1 lacking phosphatidylinositol 5-phosphate-binding and membrane-tubulating activities. Consistent with a defect of BIN1, muscle T tubules are altered in people with myotonic dystrophy, and membrane structures are restored upon expression of the normal splicing form of BIN1 in muscle cells of such individuals. Finally, reproducing BIN1 splicing alteration in mice is sufficient to promote T tubule alterations and muscle weakness, a predominant feature of myotonic dystrophy. 相似文献
100.
Mammadov R Mammadov B Toksoz S Aydin B Yagci R Tekinay AB Guler MO 《Biomacromolecules》2011,12(10):3508-3519
New blood vessel formation (angiogenesis) is one of the most important processes required for functional tissue formation. Induction of angiogenesis is usually triggered by growth factors released by cells. Glycosaminoglycans (e.g., heparan sulphates) in the extracellular matrix aid in proper functioning of these growth factors. Therefore, exogeneous heparin or growth factors were required for promoting angiogenesis in previous regenerative medicine studies. Here we report for the first time induction of angiogenesis by a synthetic nanofibrous peptide scaffold without the addition of any exogenous growth factors or heparin. We designed and synthesized a self-assembling peptide amphiphile molecule that is functionalized with biologically active groups to mimic heparin. Like heparin, this molecule has the ability to interact with growth factors and effectively enhance their bioactivity. The nanofibers formed by these molecules were shown to form a 3D network mimicking the structural proteins in the extracellular matrix. Because of heparin mimicking capabilities of the peptide nanofibers, angiogenesis was induced without the addition of exogenous growth factors in vitro. Bioactive interactions between the nanofibers and the growth factors enabled robust vascularization in vivo as well. Heparin mimetic peptide nanofibers presented here provide new opportunities for angiogenesis and tissue regeneration by avoiding the use of heparin and exogenous growth factors. The synthetic peptide nanofiber scaffolds enriched with proper chemical functional groups shown in this study can be used to induce various desired physiological responses for tissue regeneration. 相似文献