全文获取类型
收费全文 | 774篇 |
免费 | 34篇 |
出版年
2023年 | 4篇 |
2022年 | 7篇 |
2021年 | 20篇 |
2020年 | 7篇 |
2019年 | 19篇 |
2018年 | 14篇 |
2017年 | 16篇 |
2016年 | 27篇 |
2015年 | 33篇 |
2014年 | 50篇 |
2013年 | 57篇 |
2012年 | 73篇 |
2011年 | 60篇 |
2010年 | 39篇 |
2009年 | 28篇 |
2008年 | 42篇 |
2007年 | 35篇 |
2006年 | 49篇 |
2005年 | 31篇 |
2004年 | 39篇 |
2003年 | 33篇 |
2002年 | 39篇 |
2001年 | 3篇 |
2000年 | 7篇 |
1999年 | 8篇 |
1998年 | 7篇 |
1996年 | 4篇 |
1995年 | 4篇 |
1994年 | 1篇 |
1993年 | 6篇 |
1992年 | 4篇 |
1991年 | 2篇 |
1990年 | 1篇 |
1989年 | 5篇 |
1988年 | 1篇 |
1987年 | 2篇 |
1985年 | 6篇 |
1984年 | 3篇 |
1983年 | 1篇 |
1982年 | 3篇 |
1981年 | 2篇 |
1980年 | 2篇 |
1979年 | 1篇 |
1978年 | 1篇 |
1977年 | 3篇 |
1976年 | 1篇 |
1974年 | 1篇 |
1973年 | 1篇 |
1971年 | 3篇 |
1969年 | 2篇 |
排序方式: 共有808条查询结果,搜索用时 15 毫秒
201.
The bodies of primary sensory neurons and their satellite glial cells (SGCs) are limited by the basal laminae from extracellular matrix of the dorsal root ganglia (DRG). The basal laminae displayed uniform immunofluorescence staining for laminin-1 in the sections of rat intact (naive) DRG. A proximal or distal ligature of the spinal nerves resulted in a heterogeneous immunostaining for laminin-1 around neuron-SGC units in the sections of the corresponding DRG. The pattern of irregular laminin-1 immunofluorescence was more extensive in the ipsilateral than the contralateral DRG of the operated rats. The immunofluorescence for laminin-1 exactly coincided with binding of Concanavalin-A as well as immunostaining for type IV collagen in both naive DRG and DRG affected by nerve ligature. Nidogen immunostaining decreased or fully disappeared at the surface of the SGCs consistently with immunofluorescence staining for laminin-1, but retained or increased in the endothelial cells and ED-1 positive cells invaded the DRG affected by nerve ligature. The results indicate an alteration of the content of basal laminae surrounding the bodies of primary sensory neurons and their SGSs following nerve constriction injury. A modulation of the basal laminae may be related with other cellular and molecular alterations related with peripheral neuropathic pain, for example, expansion of sympathetic sprouts. 相似文献
202.
Rivkin A Kim YR Goulet MT Bays N Hill AD Kariv I Krauss S Ginanni N Strack PR Kohl NE Chung CC Varnerin JP Goudreau PN Chang A Tota MR Munoz B 《Bioorganic & medicinal chemistry letters》2006,16(17):4620-4623
A series of 3-aryl-4-hydroxyquinolin-2(1H)-ones with fatty acid synthase inhibitory activity was prepared. Starting from a derivative with an IC(50) = 1.4 microM, SAR studies led to compounds with more than 70-fold increase in potency (IC(50) < 20 nM). 相似文献
203.
204.
Toxic effects of metals appear to be partly related to the production of reactive oxygen species (ROS), which can cause oxidative damage to cells. The ability of several redox active metals [Fe(III), Cu(II), Ag(I), Cr(III), Cr(VI)], nonredox active metals [Pb(II), Cd(II), Zn(II)], and the metalloid As(III) and As(V) to produce ROS at environmentally relevant metal concentrations was assessed. Cells of the freshwater alga Chlamydomonas reinhardtii P. A. Dang. were exposed to various metal concentrations for 2.5 h. Intracellular ROS accumulation was detected using an oxidation‐sensitive reporter dye, 5‐(and‐6)‐carboxy‐2′,7′‐dihydrodifluorofluorescein diacetate (H2DFFDA), and changes in the fluorescence signal were quantified by flow cytometry (FCM). In almost all cases, low concentrations of both redox and nonredox active metals enhanced intracellular ROS levels. The hierarchy of maximal ROS induction indicated by the increased number of stained cells compared to the control sample was as follows: Pb(II) > Fe(III) > Cd(II) > Ag(I) > Cu(II) > As(V) > Cr(VI) > Zn(II). As(III) and Cr(III) had no detectable effect. The effective free metal ion concentrations ranged from 10?6 to 10?9 M, except in the case of Fe(III), which was effective at 10?18 M. These metal concentrations did not affect algal photosynthesis. Therefore, a slightly enhanced ROS production is a general and early response to elevated, environmentally relevant metal concentrations. 相似文献
205.
A series of 2-deoxy-hexopyranosyl derivatives of uridine have been synthesized as analogues of UDP-sugar. These compounds were tested as inhibitors against bovine β-1,4-galactosyltransferase I in fluorescent assays and showed no significant inhibition. 相似文献
206.
Verena Ilona Carrara Julien Zwang Elizabeth A. Ashley Ric N. Price Kasia Stepniewska Marion Barends Alan Brockman Tim Anderson Rose McGready Lucy Phaiphun Stephane Proux Michele van Vugt Robert Hutagalung Khin Maung Lwin Aung Pyae Phyo Piyanuch Preechapornkul Mallika Imwong Sasithon Pukrittayakamee Pratap Singhasivanon Nicholas J. White Fran?ois Nosten 《PloS one》2009,4(2)
Background
Artemisinin combination treatments (ACT) are recommended as first line treatment for falciparum malaria throughout the malaria affected world. We reviewed the efficacy of a 3-day regimen of mefloquine and artesunate regimen (MAS3), over a 13 year period of continuous deployment as first-line treatment in camps for displaced persons and in clinics for migrant population along the Thai-Myanmar border.Methods and Findings
3,264 patients were enrolled in prospective treatment trials between 1995 and 2007 and treated with MAS3. The proportion of patients with parasitaemia persisting on day-2 increased significantly from 4.5% before 2001 to 21.9% since 2002 (p<0.001). Delayed parasite clearance was associated with increased risk of developing gametocytaemia (AOR = 2.29; 95% CI, 2.00–2.69, p = 0.002). Gametocytaemia on admission and carriage also increased over the years (p = 0.001, test for trend, for both). MAS3 efficacy has declined slightly but significantly (Hazards ratio 1.13; 95% CI, 1.07–1.19, p<0.001), although efficacy in 2007 remained well within acceptable limits: 96.5% (95% CI, 91.0–98.7). The in vitro susceptibility of P. falciparum to artesunate increased significantly until 2002, but thereafter declined to levels close to those of 13 years ago (geometric mean in 2007: 4.2 nM/l; 95% CI, 3.2–5.5). The proportion of infections caused by parasites with increased pfmdr1 copy number rose from 30% (12/40) in 1996 to 53% (24/45) in 2006 (p = 0.012, test for trend).Conclusion
Artesunate-mefloquine remains a highly efficacious antimalarial treatment in this area despite 13 years of widespread intense deployment, but there is evidence of a modest increase in resistance. Of particular concern is the slowing of parasitological response to artesunate and the associated increase in gametocyte carriage. 相似文献207.
Coumarin-type anticoagulants, warfarin, phenprocoumon and acenocoumarol, were tested for their stereoselective binding to the human orosomucoid (ORM; AGP) genetic variants ORM 1 and ORM 2. Direct binding studies with racemic ligands were carried out by the ultrafiltration method; the concentrations of free enantiomers were determined by capillary electrophoresis. The binding of pure enantiomers was investigated with quinaldine red fluorescence displacement measurements. Our results demonstrated that all investigated compounds bind stronger to ORM 1 variant than to ORM 2. ORM 1 and human native AGP preferred the binding of (S)-enantiomers of warfarin and acenocoumarol, while no enantioselectivity was observed in phenprocoumon binding. Acenocoumarol possessed the highest enantioselectivity in AGP binding due to the weak binding of its (R)-enantiomer. Furthermore, a new homology model of AGP was built and the models of ORM 1 and ORM 2 suggested that difference in binding to AGP genetic variants is caused by steric factors. 相似文献
208.
Monique Juergens Claudia Paetsch Ilona Krämer Marc Zahn Frank Rabenstein Jörg Schondelmaier Edgar Schliephake Rod Snowdon Wolfgang Friedt Frank Ordon 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》2010,120(4):735-744
The aphid transmitted Turnip yellows virus (TuYV) has become a serious pathogen in many rapeseed (Brassica napus L.) growing areas. Three-years’ field trials were carried out to get detailed information on the genetics of TuYV resistance
derived from the resynthesised B. napus line ‘R54’ and to develop closely linked markers. F1 plants and segregating doubled-haploid (DH) populations derived from crosses to susceptible cultivars were analysed using
artificial inoculation with virus-bearing aphids, followed by DAS-ELISA. Assuming a threshold of E
405 = 0.1 in ELISA carried out in December, the results led to the conclusion that pre-winter inhibition of TuYV is inherited
in a monogenic dominant manner. However, the virus titre in most resistant lines increased during the growing period, indicating
that the resistance is incomplete and that the level of the virus titre is influenced by environmental factors. Bulked-segregant
marker analysis for this resistance locus identified two closely linked SSR markers along with six closely linked and three
co-segregating AFLP markers. Two AFLP markers were converted into co-dominant STS markers, facilitating efficient marker-based
selection for TuYV resistance. Effective markers are particularly valuable with respect to breeding for TuYV resistance, because
artificial inoculation procedures using virus-bearing aphids are extremely difficult to integrate into practical rapeseed
breeding programs. 相似文献
209.
210.
Selective binding interactions of deramciclane to the genetic variants of human α1-acid glycoprotein
Ilona Fitos Júlia VisyMiklós Simonyi György MádyFerenc Zsila 《Biochimica et Biophysica Acta (BBA)/General Subjects》2010