全文获取类型
收费全文 | 463篇 |
免费 | 36篇 |
出版年
2022年 | 4篇 |
2021年 | 9篇 |
2020年 | 4篇 |
2019年 | 4篇 |
2018年 | 9篇 |
2017年 | 4篇 |
2016年 | 9篇 |
2015年 | 19篇 |
2014年 | 18篇 |
2013年 | 15篇 |
2012年 | 27篇 |
2011年 | 24篇 |
2010年 | 15篇 |
2009年 | 16篇 |
2008年 | 26篇 |
2007年 | 18篇 |
2006年 | 33篇 |
2005年 | 16篇 |
2004年 | 18篇 |
2003年 | 10篇 |
2002年 | 10篇 |
2001年 | 14篇 |
2000年 | 15篇 |
1999年 | 17篇 |
1998年 | 11篇 |
1997年 | 7篇 |
1996年 | 6篇 |
1995年 | 10篇 |
1994年 | 8篇 |
1993年 | 5篇 |
1992年 | 7篇 |
1991年 | 9篇 |
1990年 | 4篇 |
1989年 | 9篇 |
1988年 | 5篇 |
1987年 | 5篇 |
1986年 | 4篇 |
1984年 | 3篇 |
1982年 | 4篇 |
1981年 | 3篇 |
1978年 | 4篇 |
1977年 | 5篇 |
1972年 | 2篇 |
1971年 | 2篇 |
1970年 | 2篇 |
1969年 | 3篇 |
1965年 | 2篇 |
1963年 | 2篇 |
1962年 | 2篇 |
1876年 | 2篇 |
排序方式: 共有499条查询结果,搜索用时 15 毫秒
21.
Beinke Christina Scherthan Harry Port Matthias Popp Tanja Hermann Cornelius Eder Stefan 《Radiation and environmental biophysics》2020,59(3):461-472
Radiation and Environmental Biophysics - Ionizing radiation produces reactive oxygen species (ROS) leading to cellular DNA damage. Therefore, patients undergoing radiation therapy or first... 相似文献
22.
Two silicone coatings have been evaluated for barnacle adhesion. One coating is an unfilled hydrosilation cured polydimethylsiloxane (PDMS) network, while the other is a room temperature vulcanized (RTV), filled, ethoxysiloxane cured PDMS elastomer, RTV11?. The adhesion strength of one species of barnacle, Balanus eburneus, to the hydrosilation coatings is in the range of 0.37–0.60 kg cm‐2 while the corresponding range for RTV11 is 0.64–0.90 kg cm‐2. The easier release of B. eburneus from the hydrosilation cured network compared to RTV11 is discussed in relationship to differences in bulk and surface properties. Preliminary results suggest bulk modulus may be the most important parameter in determining barnacle adhesion strength. In light or mechanical property analysis, a re‐evaluation of surface properties and chemical stability is presented. 相似文献
23.
24.
25.
Resource selection by juvenile pallid sturgeon Scaphirhynchus albus (Forbes and Richardson, 1905) in the channelized Missouri River,Nebraska, USA
下载免费PDF全文
![点击此处可从《Zeitschrift fur angewandte Ichthyologie》网站下载免费的PDF全文](/ch/ext_images/free.gif)
B. L. Eder B. C. Neely J. D. Haas J. D. Adams 《Zeitschrift fur angewandte Ichthyologie》2016,32(4):629-635
Habitat selection has been quantified for age‐0 and adult pallid sturgeon Scaphirhynchus albus Bull. Illinois State Lab. Nat. Hist., 7, 1905, 37, but little is known regarding habitat use of the juvenile fish. The objective of this study was to quantify habitat use and selection of juvenile pallid sturgeon in the Missouri River, Nebraska, USA. Thirty‐seven age‐4 pallid sturgeon with transmitters were released in July of 2014, plus an additional 21 in September, with habitat monitored using biotelemetry. Age‐1 and age‐4 hatchery reared pallid sturgeon were found to avoid areas associated with the outside bend and thalweg habitats that were characterized by rapid water velocity (>1 ms?1), which accounted for 50% of the area in the channelized Missouri River. Age‐1 pallid sturgeon selected an off‐channel habitat and inside bend habitat while age‐4 pallid sturgeon selected an off‐channel and inside bend channel border habitat. Juvenile pallid sturgeon in unaltered rivers have been shown to associate with island tips and sand bars, habitat that is largely absent in the channelized Missouri River. This study indicates that juvenile pallid sturgeon in the Missouri River, Nebraska are selecting habitats with shallow water and slow water velocity, similar to those associated with island tips and sand bars in unaltered reaches. 相似文献
26.
27.
Intraindividual variations of DNA adduct levels in humans 总被引:7,自引:0,他引:7
Eder E 《Mutation research》1999,424(1-2):249-261
Reports on intraindividual changes of DNA adduct levels in humans are rare. Most of the data available in the literature are from polycyclic aromatic hydrocarbons (PAHs) and are measured in white blood cells with 32P-postlabeling or immunochemical assays. Surprisingly, environmental exposure can have a larger effect on PAH adduct levels than occupational exposure, food or smoking. Highest (13-fold) summer/winter increments, due to indoor heating were observed in Gliwice, Poland. Further studies of environmental PAH exposure confirm the environmental influence on intraindividual changes in PAHs-DNA adduct levels: studies of the Teplice program, (Czech Republic) and studies with US soldiers, stationed in Germany who went for a 8-week period of duty to Kuwait. Variations in occupational exposure, e.g., changing of anode material in aluminium plants (elevation factor 3.94), layoffs, reduced working hours in iron foundries or vacation also led to intraindividual changes in PAH adduct levels. Increase in PAH adduct levels after consumption of charcoal broiled meat evidently depends on individual susceptibility, e.g., polymorphism. In one person a 7.4-fold increment was observed. PAH adduct levels were not significantly influenced by smoking cessation whereas sister chromatid exchanges significantly decreased. Changes in occupational exposure to styrene in lamination plants, e.g., due to vacation, did not significantly influence styrene-O6-dG adduct levels in lymphocytes and granulocytes as determined by 32P-postlabeling. Increase of N7-methylguanine and O6-methylguanine levels were followed in white blood cells during treatment of cancer patients with dacarbazine and allowed insights into pharmacokinetic properties. According to a rough estimation the high increment in the PAHs-DNA adduct level of about 13 observed in Gliwice (see above) would result in a tentative increase in cancer risk from about 1 death/107 inhabitants to approximately 10 deaths/107 inhabitants which, in general, is considered as acceptable. 相似文献
28.
Monteiro-Vitorello CB Camargo LE Van Sluys MA Kitajima JP Truffi D do Amaral AM Harakava R de Oliveira JC Wood D de Oliveira MC Miyaki C Takita MA da Silva AC Furlan LR Carraro DM Camarotte G Almeida NF Carrer H Coutinho LL El-Dorry HA Ferro MI Gagliardi PR Giglioti E Goldman MH Goldman GH Kimura ET Ferro ES Kuramae EE Lemos EG Lemos MV Mauro SM Machado MA Marino CL Menck CF Nunes LR Oliveira RC Pereira GG Siqueira W de Souza AA Tsai SM Zanca AS Simpson AJ Brumbley SM Setúbal JC 《Molecular plant-microbe interactions : MPMI》2004,17(8):827-836
The genome sequence of Leifsonia xyli subsp. xyli, which causes ratoon stunting disease and affects sugarcane worldwide, was determined. The single circular chromosome of Leifsonia xyli subsp. xyli CTCB07 was 2.6 Mb in length with a GC content of 68% and 2,044 predicted open reading frames. The analysis also revealed 307 predicted pseudogenes, which is more than any bacterial plant pathogen sequenced to date. Many of these pseudogenes, if functional, would likely be involved in the degradation of plant heteropolysaccharides, uptake of free sugars, and synthesis of amino acids. Although L. xyli subsp. xyli has only been identified colonizing the xylem vessels of sugarcane, the numbers of predicted regulatory genes and sugar transporters are similar to those in free-living organisms. Some of the predicted pathogenicity genes appear to have been acquired by lateral transfer and include genes for cellulase, pectinase, wilt-inducing protein, lysozyme, and desaturase. The presence of the latter may contribute to stunting, since it is likely involved in the synthesis of abscisic acid, a hormone that arrests growth. Our findings are consistent with the nutritionally fastidious behavior exhibited by L. xyli subsp. xyli and suggest an ongoing adaptation to the restricted ecological niche it inhabits. 相似文献
29.
Vincentz M Cara FA Okura VK da Silva FR Pedrosa GL Hemerly AS Capella AN Marins M Ferreira PC França SC Grivet L Vettore AL Kemper EL Burnquist WL Targon ML Siqueira WJ Kuramae EE Marino CL Camargo LE Carrer H Coutinho LL Furlan LR Lemos MV Nunes LR Gomes SL Santelli RV Goldman MH Bacci M Giglioti EA Thiemann OH Silva FH Van Sluys MA Nobrega FG Arruda P Menck CF 《Plant physiology》2004,134(3):951-959
30.
Catanozi S Rocha JC Passarelli M Guzzo ML Alves C Furukawa LN Nunes VS Nakandakare ER Heimann JC Quintão EC 《Journal of lipid research》2003,44(4):727-732
This study aimed at measuring the influence of a low salt diet on the development of experimental atherosclerosis in moderately hyperlipidemic mice. Experiments were carried out on LDL receptor (LDLR) knockout (KO) mice, or apolipoprotein E (apoE) KO mice on a low sodium chloride diet (LSD) as compared with a normal salt diet (NSD). On LSD, the rise of the plasma concentrations of TG and nonesterified fatty acid (NEFA) was, respectively, 19% and 34% in LDLR KO mice, and 21% and 35% in apoE KO mice, and that of plasma cholesterol was limited to the LDLR KO group alone (15%). Probably due to the apoE KO severe hypercholesterolemia, the arterial inner-wall fat storage was not influenced by the diet salt content and was far more abundant in the apoE KO than in the LDLR KO mice. However, in the less severe hypercholesterolemia of the LDLR KO mice, lipid deposits on the LSD were greater than on the NSD. Arterial fat storage correlated with NEFA concentrations in the LDLR KO mice alone (n = 14, P = 0.0065). Thus, dietary sodium chloride restriction enhances aortic wall lipid storage in moderately hyperlipidemic mice. 相似文献