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161.
Expression of the alcohol dehydrogenase gene ADH1, which converts ethanol into carcinogenic acetaldehyde, significantly inversely correlated with the expression of CDR1 and CDR2, genes linked to azole resistance in Candida albicans isolated from chronic oral candidosis in autoimmune polyendocrinopathy-candidosis-ectodermal dystrophy (APECED, APS-I) patients. This is a novel link between candidal two-carbon metabolism genes and azole resistance.  相似文献   
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The differentiation of human primary T helper 1 (Th1) cells from naïve precursor cells is regulated by a complex, interrelated signaling network. The identification of factors regulating the early steps of Th1 cell polarization can provide important insight in the development of therapeutics for many inflammatory and autoimmune diseases. The serine/threonine-specific proviral integration site for Moloney murine leukemia virus (PIM) kinases PIM1 and PIM2 have been implicated in the cytokine-dependent proliferation and survival of lymphocytes. We have established that the third member of this family, PIM3, is also expressed in human primary Th cells and identified a new function for the entire PIM kinase family in T lymphocytes. Although PIM kinases are expressed more in Th1 than Th2 cells, we demonstrate here that these kinases positively influence Th1 cell differentiation. Our RNA interference results from human primary Th cells also suggest that PIM kinases promote the production of IFNγ, the hallmark cytokine produced by Th1 cells. Consistent with this, they also seem to be important for the up-regulation of the critical Th1-driving factor, T box expressed in T cells (T-BET), and the IL-12/STAT4 signaling pathway during the early Th1 differentiation process. In summary, we have identified PIM kinases as new regulators of human primary Th1 cell differentiation, thus providing new insights into the mechanisms controlling the selective development of human Th cell subsets.  相似文献   
165.
Acetone-soluble compounds found in different root zones and stumps of Norway spruce (Picea abies [L.] Karst), which were grown on either peatland or a mineral soil site, were studied. Samples from stumps and roots of different sizes and ages were collected a day after the trees were felled. The wood and bark of stumps and three zones of the roots were separated and extracted with acetone in an ultrasonic bath. Extracts were silylated and analysed by gas chromatography–mass spectrometry. The stilbene glucosides astringin and isorhapontin were major compounds in the spruce bark samples. The resveratrol glucoside piceid and the flavonoid catechin were also extracted from spruce bark. We also found the lignan hydroxymatairesinol in some wood extracts. Total concentrations of stilbene glucosides in bark of stumps and different root zones varied between 0.53 and 8.29 % (w/w, dry weight) with isorhapontin being the major compound. Isorhapontin concentrations were highest in the spruce samples grown on mineral soil. The bark of the roots close to the stem is a rich source of stilbenes for commercial utilisation.  相似文献   
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For women, menopausal transition is a time of significant hormonal changes, which may contribute to altered body composition and regional adipose tissue accumulation. Excess adiposity, and especially adipose tissue accumulation in the central body region, increases women''s risk of cardiovascular and metabolic conditions and affects physical functioning. We investigated the associations between menopausal progression and total and regional body adiposity measured with dual‐energy X‐ray absorptiometry and computed tomography in two longitudinal cohort studies of women aged 47–55 (n = 230 and 148, mean follow‐up times 1.3 ± 0.7 and 3.9 ± 0.2 years, mean baseline BMI 25.5 kg/m2). We also examined associations between menopausal progression and skeletal muscle fiber characteristics, as well as adipose tissue‐derived adipokines. Relative increases of 2%–14% were observed in regional and total body adiposity measures, with a pronounced fat mass increase in the android area (4% and 14% during short‐ and long‐term follow‐ups). Muscle fiber oxidative and glycolytic capacities and intracellular adiposity were not affected by menopause, but were differentially correlated with total and regional body adiposity at different menopausal stages. Menopausal progression and regional adipose tissue masses were positively associated with serum adiponectin and leptin, and negatively associated with resistin levels. Higher diet quality and physical activity level were also inversely associated with several body adiposity measures. Therefore, healthy lifestyle habits before and during menopause might delay the onset of severe metabolic conditions in women.  相似文献   
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This study aims to identify how climate change may influence total emissions of monoterpene and isoprene from boreal forest canopies. The whole of Finland is assumed to experience an annual mean temperature (T) increase of 4 °C and a precipitation increase of 10% by the year 2100. This will increase forest resources throughout the country. At the same time, the proportions of Scots pine (Pinus sylvestris) and Norway spruce (Picea abies) in southern Finland (60°≤ latitude < 65°N) will be reduced from the current 40–50% to less than 10–20%, with increased dominance of birches (Betula pendula and Betula pubescens). In northern Finland (65°≤ latitude < 70°N), the proportions of Norway spruce and Scots pine will be balanced at a level of about 40% as the result of an increase in Norway spruce from the current 21% to 37% and a concurrent reduction in Scots pine from 63% to 40%. The proportion of birches is predicted to increase from the current 17% to 23%, but these will become the dominant species only on the most fertile sites. Total mean emissions of monoterpene by Scots pine will be reduced by 80% in southern Finland, but will increase by 62% in the north. Emissions from Norway spruce canopies will increase by 4% in the south but by 428% in the north, while those from birch canopies will increase by about 300% and 113%, respectively. Overall emissions of monoterpene over the whole country amount to about 950 kg km?2 y?1 under current temperature conditions and will increase by 17% to 1100 kg km?2 y?1 with elevated temperature and precipitation, mainly because of an increase at northern latitudes. Under current conditions, emissions of isoprene follow the spatial distribution of spruce canopies (the only isoprene‐emitting tree species that forms forests in Finland) with four times higher emissions in the south than in the north. The elevated temperature and the changes in the areal distribution of Norway spruce will result in increases in isoprene emissions of about 37% in southern Finland and 435% in northern Finland. Annual mean isoprene emissions from Norway spruce canopies over the whole country will increase by about 60% up to the year 2100.  相似文献   
169.
Importance of the Hsp70 ATPase domain in yeast prion propagation   总被引:1,自引:0,他引:1       下载免费PDF全文
Loovers HM  Guinan E  Jones GW 《Genetics》2007,175(2):621-630
The Saccharomyces cerevisiae non-Mendelian genetic element [PSI+] is the prion form of the translation termination factor Sup35p. The ability of [PSI+] to propagate efficiently has been shown previously to depend upon the action of protein chaperones. In this article we describe a genetic screen that identifies an array of mutants within the two major cytosolic Hsp70 chaperones of yeast, Ssa1p and Ssa2p, which impair the propagation of [PSI+]. All but one of the mutants was located within the ATPase domain of Hsp70, which highlights the important role of regulation of Hsp70-Ssa ATP hydrolysis in prion propagation. A subset of mutants is shown to alter Hsp70 function in a way that is distinct from that of previously characterized Hsp70 mutants that alter [PSI+] propagation and supports the importance of interdomain communication and Hsp70 interaction with nucleotide exchange factors in prion propagation. Analysis of the effects of Hsp70 mutants upon propagation of a second yeast prion [URE3] further classifies these mutants as having general or prion-specific inhibitory properties.  相似文献   
170.
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