全文获取类型
收费全文 | 915篇 |
免费 | 127篇 |
出版年
2023年 | 9篇 |
2022年 | 5篇 |
2021年 | 17篇 |
2020年 | 13篇 |
2019年 | 27篇 |
2018年 | 21篇 |
2017年 | 27篇 |
2016年 | 31篇 |
2015年 | 48篇 |
2014年 | 41篇 |
2013年 | 51篇 |
2012年 | 58篇 |
2011年 | 53篇 |
2010年 | 33篇 |
2009年 | 31篇 |
2008年 | 40篇 |
2007年 | 42篇 |
2006年 | 45篇 |
2005年 | 36篇 |
2004年 | 31篇 |
2003年 | 36篇 |
2002年 | 28篇 |
2001年 | 36篇 |
2000年 | 24篇 |
1999年 | 20篇 |
1998年 | 16篇 |
1997年 | 9篇 |
1996年 | 12篇 |
1995年 | 13篇 |
1994年 | 17篇 |
1993年 | 11篇 |
1992年 | 18篇 |
1991年 | 17篇 |
1990年 | 9篇 |
1989年 | 18篇 |
1988年 | 17篇 |
1987年 | 10篇 |
1986年 | 12篇 |
1985年 | 15篇 |
1984年 | 5篇 |
1983年 | 4篇 |
1982年 | 6篇 |
1980年 | 5篇 |
1979年 | 2篇 |
1978年 | 2篇 |
1977年 | 2篇 |
1976年 | 4篇 |
1974年 | 2篇 |
1966年 | 3篇 |
1960年 | 2篇 |
排序方式: 共有1042条查询结果,搜索用时 250 毫秒
111.
112.
113.
R. Mioso F.J. Toledo Marante I. Herrera Bravo de Laguna 《Journal of applied microbiology》2015,118(4):781-791
This is a comprehensive review, with 114 references, of the chemical diversity found in the fungus Penicillium roqueforti. Secondary metabolites of an alkaloidal nature are described, for example, ergot alkaloids such as festuclavine, isofumigaclavines A and B, and diketopiperazine alkaloids such as roquefortines A–D, which are derived from imidazole. Other metabolites are marcfortines A–C, PR‐toxin, eremofortines A–E, mycophenolic and penicillic acids, and some γ‐lactones. Also, recent developments related to the structural characteristics of botryodiplodin and andrastin are studied—the latter has anticancer properties. Finally, we discuss the enzymes of P. roqueforti, which can participate in the biotechnological production of high value‐added molecules, as well as the use of secondary metabolite profiles for taxonomic purposes. 相似文献
114.
Background
A recent epidemiological study demonstrated a reduced risk of lung cancer mortality in breast cancer patients using antiestrogens. These and other data implicate a role for estrogens in lung cancer, particularly nonsmall cell lung cancer (NSCLC). Approximately 61% of human NSCLC tumors express nuclear estrogen receptor β (ERβ); however, the role of ERβ and estrogens in NSCLC is likely to be multifactorial. Here we tested the hypothesis that proteins interacting with ERβ in human lung adenocarcinoma cells that respond proliferatively to estradiol (E2) are distinct from those in non-E2-responsive cells.Methods
FLAG affinity purification of FLAG-ERβ-interacting proteins was used to isolate ERβ-interacting proteins in whole cell extracts from E2 proliferative H1793 and non-E2-proliferative A549 lung adenocarcinoma cell lines. Following trypsin digestion, proteins were identified using liquid chromatography electrospray ionization tandem mass spectrometry (LC-MS/MS). Proteomic data were analyzed using Ingenuity Pathway Analysis. Select results were confirmed by coimmunoprecipitation.Results
LC-MS/MS identified 27 non-redundant ERβ-interacting proteins. ERβ-interacting proteins included hsp70, hsp60, vimentin, histones and calmodulin. Ingenuity Pathway Analysis of the ERβ-interacting proteins revealed differences in molecular and functional networks between H1793 and A549 lung adenocarcinoma cells. Coimmunoprecipitation experiments in these and other lung adenocarcinoma cells confirmed that ERβ and EGFR interact in a gender-dependent manner and in response to E2 or EGF. BRCA1 interacted with ERβ in A549 cell lines and in human lung adenocarcinoma tumors, but not normal lung tissue.Conclusion
Our results identify specific differences in ERβ-interacting proteins in lung adenocarcinoma cells corresponding to ligand-dependent differences in estrogenic responses.115.
Bakker MF Verstappen SM Welsing PM Jacobs JW Jahangier ZN van der Veen MJ Bijlsma JW Lafeber FP;Utrecht Arthritis Cohort study group 《Arthritis research & therapy》2011,13(3):R70
Introduction
The aim of this study was to investigate whether serum biomarker levels of C2C, C1,2C, CS846, and CPII can predict the long-term course of disease activity and radiographic progression early in the disease course of rheumatoid arthritis (RA). 相似文献116.
Gottschling M Bravo IG Schulz E Bracho MA Deaville R Jepson PD Van Bressem MF Stockfleth E Nindl I 《Molecular phylogenetics and evolution》2011,59(1):34-42
The phylogenetic position of cetacean papillomaviruses (PVs: Omikron-PVs and Upsilon-PVs) varies depending on the region of the genome analysed. They cluster together with Alpha-PVs when analysing early genes and with Xi-PVs and Phi-PVs when analysing late genes. We cloned and sequenced the complete genomes of five novel PVs, sampled from genital and oesophageal lesions of free-ranging cetaceans: Delphinus delphis (DdPV1), Lagenorhynchus acutus (TtPV3 variant), and Phocoena phocoena (PphPV1, PphPV2, and PphPV3). Using Maximum Likelihood and Bayesian approaches, all cetacean PVs constituted a monophyletic group with Alpha-, Omega-, and Dyodelta-PVs as inferred from E1-E2 early genes analyses, thus matching the shared phenotype of mucosal tropism. However, cetacean PVs, with the exception of PphPV3, were the closest relatives of Xi-PVs and Phi-PVs in L2-L1 late genes analyses, isolated from cow and goat, thus reflecting the close relationship between Cetacea and Artiodactyla. Our results are compatible with a recombination between ancestral PVs infecting the Cetartiodactyla lineage. Our study supports a complex evolutionary scenario with multiple driving forces for PV diversification, possibly including recombination and also interspecies transmission. 相似文献
117.
Hong E Larios F Gómez-Viquez NL Huang F Bravo G 《Journal of physiology and biochemistry》2011,67(3):427-435
The contribution of α-adrenoceptors and nitric oxide (NO) on the alterations of sympathetically mediated cardiovascular responses
after acute (AcH) and chronic (ChH) hypertension was evaluated in pithed aortic coarcted hypertensive rats. Pressor and tachycardia
response produced by electrical stimulation of preganglionic sympathetic fibers or exogenous noradrenaline (NA) were recorded
in the absence and presence of prazosin (α1-antagonist), rauwolscine (α2-antagonist), or N
G-nitro-l-arginine methyl ester (l-NAME; an inhibitor of NO synthase). Compared with age-matched sham-operated rats (Nt), the pressor response produced by electrical
stimulation or NA was smaller in AcH rats and larger in ChH rats. Prazosin caused a decrease of pressor response elicited
by electrical stimulation or NA in all groups. However, this effect was higher in ChH. Rauwolscine produced a similar increase
of sympathetically mediated pressor response in Nt and AcH rats. Nevertheless, this antagonist did not affect the sympathetically
mediated pressor response in ChH rats. In addition, rauwolscine did not affect the NA-induced pressor response in all groups.
The pressor response elicited by l-NAME was larger in all groups compared without l-NAME and in presence of l-arginine. Moreover, l-NAME in the presence of NA increased sympathetically mediated pressor response is in all groups, compared without it or in
the presence of l-arginine. Compared with Nt, basally produced NO in aortic rings was increased in AcH but decreased in ChH. Collectively,
our data suggest that decreased cardiovascular reactivity in AcH is due to an increase in basally produced NO. In ChH, enhanced
cardiovascular response appears to be associated with a decrease in produced NO and an increase in released NA from sympathetic
nerves. 相似文献
118.
The type specimens of Neodiogmites hirtuosus (Wiedemann, 1821), two males and one female, deposited at the Museum für Naturkunde der Humboldt-Universität (ZMHB), Berlin were examined. The specimens show the diagnostic characters of Apoxyria Schiner, 1866: face strongly pronounced, swollen and curved hind tibia, and terminalia with epandrium large and hypandrium short and obtuse. A new combination is suggested, Apoxyria hirtuosa (Wiedemann, 1821), and lectotype and paralectotypes are designated. The species is redescribed, the male terminalia is described and illustrated for the first time, and an identification key to Apoxyria is presented. 相似文献
119.
120.
The effect of the dilution rate on biomass and product synthesis in fermentations of glucose, fructose and a commercial mixture of fructooligosaccharides (FOS) by Bifidobacterium longum ATCC 15707 was studied. Kinetic parameters (maximum specific growth rate, Monod constant, maintenance, and yield coefficients) in the mathematical model of the fermentation were estimated from experimental data. In the FOS mixture fermentations, approximately 12% of the total reducing sugars (mainly fructose) in the feed were not metabolized by the bacterium. In fermentations of fructose and the FOS mixture, biomass concentration increased as the dilution rate increased and, once maximum values were reached [3.90 (D=0.20 h–1) and 2.54 g l–1 (D=0.15 h–1), respectively], decreased rapidly as the culture was washed out. Formic acid was detected at low dilution rates in glucose and fructose fermentations. The main products in fermentations of the three carbon sources were lactic and acetic acids. Average values of the molar ratio between acetic and lactic acids of 1.18, 1.21 and 0.83 mol mol–1 were obtained in glucose, fructose and FOS mixture fermentations, respectively. In batch fermentations carried out without pH control this molar ratio was lower than 1.5 only when fructose was used as the carbon source. 相似文献