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31.
J E Paulsen K L Reichelt A K Petersen 《Virchows Archiv. B, Cell pathology including molecular pathology》1987,54(3):152-154
A pentapeptide isolated from normal mouse liver seems to inhibit DNA synthesis (3H-thymidine incorporation into liver DNA and labeling indices) and the mitotic rate (G2-M cell flux) in regenerating mouse liver. The inhibitor is somewhat similar to the growth inhibitory pentapeptides previously reported for granulocytes and epidermis. It is active at very low dose levels, showing a bell-shaped dose-response curve. 相似文献
32.
Effect of sodium chloride on growth of heterotrophic marine bacteria 总被引:13,自引:0,他引:13
33.
Activation of hypothalamic RIP‐Cre neurons promotes beiging of WAT via sympathetic nervous system 下载免费PDF全文
Baile Wang Ang Li Xiaomu Li Philip WL Ho Donghai Wu Xiaoqi Wang Zhuohao Liu Kelvin KL Wu Sonata SY Yau Aimin Xu Kenneth KY Cheng 《EMBO reports》2018,19(4)
Activation of brown adipose tissue (BAT) and beige fat by cold increases energy expenditure. Although their activation is known to be differentially regulated in part by hypothalamus, the underlying neural pathways and populations remain poorly characterized. Here, we show that activation of rat‐insulin‐promoter‐Cre (RIP‐Cre) neurons in ventromedial hypothalamus (VMH) preferentially promotes recruitment of beige fat via a selective control of sympathetic nervous system (SNS) outflow to subcutaneous white adipose tissue (sWAT), but has no effect on BAT. Genetic ablation of APPL2 in RIP‐Cre neurons diminishes beiging in sWAT without affecting BAT, leading to cold intolerance and obesity in mice. Such defects are reversed by activation of RIP‐Cre neurons, inactivation of VMH AMPK, or treatment with a β3‐adrenergic receptor agonist. Hypothalamic APPL2 enhances neuronal activation in VMH RIP‐Cre neurons and raphe pallidus, thereby eliciting SNS outflow to sWAT and subsequent beiging. These data suggest that beige fat can be selectively activated by VMH RIP‐Cre neurons, in which the APPL2–AMPK signaling axis is crucial for this defending mechanism to cold and obesity. 相似文献
34.
Chao T. I Grosche J Biedermann B Francke M Pannicke T Reichelt W Wulst M Muhle C Pritz-Hohmeier S Kuhrt H Faude F Drommer W Kasper M Buse E Reichenbach A 《Brain Cell Biology》1997,26(7):439-454
Brain Cell Biology - Muller cells from 22 mammalian species were subjected to morphological and electrophysiological studies. In the ‘mid-periphery’ of retinae immunocytochemically... 相似文献
35.
Taxonomy of Marine Bacteria: Beneckea parahaemolytica and Beneckea alginolytica 总被引:12,自引:2,他引:10 下载免费PDF全文
A collection of 169 strains, including 91 obtained from cases of gastroenteritis and 41 from localized tissue infections and infections of the eye and ear, was submitted to an extensive nutritional, physiological, and morphological characterization. The nutritional and physiological data obtained from these strains, as well as data for strains of other species of the genus Beneckea, were submitted to a numerical analysis which grouped the strains into clusters on the basis of phenotypic similarity. Strains from cases of gastroenteritis formed a group of three clusters which linked at a similarity value of 68%. These three clusters could not, however, be separated from each other by universally positive or negative traits, and on the basis of their overall phenotypic similarity were assigned to a single species, B. parahaemolytica. The majority of the strains from human, nonenteric sources segregated into two distinct clusters, one designated B. alginolytica and the other unassigned with respect to species (group C-2). B. parahaemolytica, B. alginolytica, and group C-2 could be readily distinguished from one another as well as from the remaining species of the genus Beneckea by multiple, unrelated, phenotypic traits. Activities of selected enzymes of glucose and gluconate catabolism in cell-free extracts of B. parahaemolytica, B. alginolytica, and group C-2 suggested that these organisms utilized glucose primarily via the Embden-Meyerhof pathway and gluconate primarily via the Entner-Doudoroff pathway. Similar results were observed in the other members of the genus Beneckea. 相似文献
36.
S Vrtala S Fischer M Grote L Vangelista A Pastore W R Sperr P Valent R Reichelt D Kraft R Valenta 《Journal of immunology (Baltimore, Md. : 1950)》1999,163(10):5489-5496
Due to the wide distribution and heavy pollen production of grasses, approximately 50% of allergic patients are sensitized against grass pollen allergens. cDNAs coding for two isoforms and four fragments of a major timothy grass (Phleum pratense) pollen allergen, Phl p 6, were isolated by IgE immunoscreening from a pollen expression cDNA library. Recombinant Phl p 6 (rPhl p 6), an acidic protein of 11.8 kDa, was purified to homogeneity as assessed by mass spectrometry and exhibited almost exclusive alpha-helical secondary structure as determined by circular dichroism spectroscopy. Phl p 6 reacted with serum IgE from 75% of grass pollen-allergic patients (n = 171). IgE binding experiments with rPhl p 6 fragments indicated that the N terminus of the allergen is required for IgE recognition. Purified rPhl p 6 elicited dose-dependent basophil histamine release and immediate type skin reactions in patients allergic to grass pollen. A rabbit antiserum raised against purified rPhl p 6 identified it as a pollen-specific protein that, by immunogold electron microscopy, was localized on the polysaccharide-containing wall-precursor bodies (P-particles). The association of Phl p 6 with P-particles may facilitate its intrusion into the deeper airways and thus be responsible for the high prevalence of IgE recognition of Phl p 6. Recombinant native-like Phl p 6 can be used for in vitro as well as in vivo diagnoses of grass pollen allergy, whereas N-terminal deletion mutants with reduced IgE binding capacity may represent candidates for immunotherapy of grass pollen allergy with a low risk of anaphylactic side effects. 相似文献
37.
Voelckel C Heenan PB Janssen B Reichelt M Ford K Hofmann R Lockhart PJ 《Molecular ecology》2008,17(21):4740-4753
New Zealand is diverse in alpine and subalpine environments, a consequence of Late Tertiary tectonic and climatic change. However, few studies have sought to evaluate the importance of these environments as abiotic drivers in the diversification of plant species. Of particular interest is the Late Tertiary radiation of Pachycladon, an endemic New Zealand genus of alpine cress. Here we report observations on genome-wide levels of differential expression measured in the habitats of two closely related species of Pachycladon with distinct altitudinal preferences. Using Arabidopsis microarrays, we have identified 310 predominantly hormone- and stress-response genes up-regulated in Pachycladon fastigiata and 324 genes up-regulated in Pachycladon enysii. Expression patterns for glucosinolate biosynthesis and hydrolysis genes (MAM1, MAM-I, MAM-D, AOP2, ESP, ESM1) as well as flavonoid biosynthesis genes (F3'H, FLS, FAH1) were found to be species specific. Predicted differences in flavonoid contents were partly confirmed by high performance liquid chromatography analysis. Differences in glucosinolate profiles and glucosinolate hydrolysis products obtained by high performance liquid chromatography and gas chromatography-mass spectrometry analysis, respectively, also supported inferences from expression analyses. Five glucosinolate chemotypes were matched to known Arabidopsis ecotypes, and the potential adaptive significance of these chemotypes has been discussed. Our findings, in contrast to expectations for evolution of the New Zealand flora, suggest that biotic drivers, such as plant-herbivore interactions, are likely to be as important as abiotic drivers in the diversification of Pachycladon. 相似文献
38.
Tanja Knill Michael Reichelt Christian Paetz Jonathan Gershenzon Stefan Binder 《Plant molecular biology》2009,71(3):227-239
The last steps of the Leu biosynthetic pathway and the Met chain elongation cycle for glucosinolate formation share identical
reaction types suggesting a close evolutionary relationship of these pathways. Both pathways involve the condensation of acetyl-CoA
and a 2-oxo acid, isomerization of the resulting 2-malate derivative to form a 3-malate derivative, the oxidation-decarboxylation
of the 3-malate derivative to give an elongated 2-oxo acid, and transamination to generate the corresponding amino acid. We
have now analyzed the genes encoding the isomerization reaction, the second step of this sequence, in Arabidopsis thaliana. One gene encodes the large subunit and three encode small subunits of this enzyme, referred to as isopropylmalate isomerase
(IPMI) with respect to the Leu pathway. Metabolic profiling of large subunit mutants revealed accumulation of intermediates
of both Leu biosynthesis and Met chain elongation, and an altered composition of aliphatic glucosinolates demonstrating the
function of this gene in both pathways. In contrast, the small subunits appear to be specialized to either Leu biosynthesis
or Met chain elongation. Green fluorescent protein tagging experiments confirms the import of one of the IPMI small subunits
into the chloroplast, the localization of the Met chain elongation pathway in these organelles. These results suggest the
presence of different heterodimeric IPMIs in Arabidopsis chloroplasts with distinct substrate specificities for Leu or glucosinolate
metabolism determined by the nature of the different small subunit.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. 相似文献
39.
人类端粒酶启动子(hTERT启动子)在肿瘤基因治疗中的有效性已经得到了证实. 然而,hTERT启动子有限的肿瘤靶向转录活性困扰着它的临床应用.早期研究已经揭示,核心hTERT启动子上的-34位E-box元件与该启动子的肿瘤靶向转录活性有关.为进一步探索核心hTERT启动子序列3′端富余E-box元件是否能提高启动子的肿瘤靶向转录能力,用化学合成方法在野生型hTERT(WT-hTERT)核心启动子片段(编码蛋白起始子ATG上游-268 bp~-10 bp)的3′端接入3个E-box序列, 构建成修饰型hTERT(Mod-hTERT)启动子. 然后,分别用WT-hTERT和Mod-hTERT启动子去调控增强型绿色荧光蛋白(EGFP)及荧光素酶报告基因在293FT、HepGⅡ、SGC7901、U2OS、以及原代培养人成纤维细胞(PHF)中表达. 结果表明, 在Mod-hTERT启动子的各实验组细胞中,能够在端粒酶阳性的293FT、HepGⅡ及 SGC7901细胞组中观测到EGFP的表达,而在端粒酶阴性的U2OS及PHF细胞组中没有观测到EGFP的表达;在端粒酶阳性的293FT、HepGⅡ和SGC7901细胞株中,Mod-hTERT启动子调控下的荧光素酶活性要高于WT-hTERT启动子组(P<0.01); 而在端粒酶阴性的U2OS细胞组中,Mod-hTERT启动子调控下的荧光素酶活性则低于WT-hTERT启动子组(P<0.01); 在PHF细胞组中,Mod-hTERT启动子组与WT-hTERT启动子组的荧光素酶活性差异不显著(P>0.05).研究提示,在3′端增加E-box元件可以提高核心hTERT启动子序列的肿瘤靶向转录活性. 相似文献
40.
Claudia Azucena Palafox Sánchez Minoru Satoh Edward KL Chan Wendy C Carcamo José Francisco Muñoz Valle Gerardo Orozco Barocio Edith Oregon Romero Rosa Elena Navarro Hernández Mario Salazar Páramo Antonio Cabral Castañeda Mónica Vázquez del Mercado 《Arthritis research & therapy》2009,11(1):1-12