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1.
Industrial sectors that operate in uncertain environments - with demand variability, product seasonality and different industrialisation structures - need studies that enable identification and forecast trends. Therefore, the development of competitiveness extends beyond a company’s individual performance. Collective action, whether toward consumer markets, supplier markets, competitors and substitutes, can reinforce or help reformulate the current practices of an organisation, besides providing better results in the development of strategies and competitive positioning. Thus, clothing, the sector addressed in this work, is characterised by a long, fragmented, heterogeneous production chain, the competitiveness of which is linked to product differentiation. Therefore, the use of systemic approaches to study this sector is effective. In this sense, this research aims at adapting Systems Thinking and Scenario Planning (STSP) so that it supports the development and planning process in a given sector. Thus, this research applies STSP adapted to an analysis of the clothing sector in the northern region of Rio Grande do Sul State, Brazil. As a result, in academic terms, this research proposed and validated a method for analysing industrial sectors of the clothing industry. In the sectoral context, this research identified elements that leverage the sector’s competitiveness, besides generating knowledge and learning aimed at strengthening the sectoral structure identified, and fostering the formation of a new clothing cluster.  相似文献   
2.
Detection and characterization of a folding intermediate in barnase by NMR   总被引:17,自引:0,他引:17  
Protein engineering is being developed for mapping the energetics and pathway of protein folding. From kinetic studies on wild-type and mutant proteins, the sequence and energetics of formation of tertiary interactions of side chains can be mapped and the formation of secondary structure inferred. Here we cross-check and complement results from this approach by using a recently developed procedure that traps and characterizes secondary structure in intermediate states using 1H NMR. The refolding of barnase is shown to be a multiphasic process in which the secondary structure in alpha-helices and beta-sheets and some turns is formed more rapidly than is the overall folding.  相似文献   
3.
Engineering stability in gene networks by autoregulation   总被引:47,自引:0,他引:47  
Becskei A  Serrano L 《Nature》2000,405(6786):590-593
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4.
Most preneoplastic lesions are quiescent and do not progress to form overt tumors. It has been proposed that oncogenic stress activates the DNA damage response and the key tumor suppressor p53, which prohibits tumor growth. However, the molecular pathways by which cells sense a premalignant state in vivo are largely unknown. Here we report that tissue-specific inactivation of the stress signaling kinase MKK7 in KRas(G12D)-driven lung carcinomas and NeuT-driven mammary tumors markedly accelerates tumor onset and reduces overall survival. Mechanistically, MKK7 acts through the kinases JNK1 and JNK2, and this signaling pathway directly couples oncogenic and genotoxic stress to the stability of p53, which is required for cell cycle arrest and suppression of epithelial cancers. These results show that MKK7 functions as a major tumor suppressor in lung and mammary cancer in mouse and identify MKK7 as a vital molecular sensor to set a cellular anti-cancer barrier.  相似文献   
5.
A Matouschek  J T Kellis  L Serrano  A R Fersht 《Nature》1989,340(6229):122-126
In the transition state for unfolding of barnase, the hydrophobic core between the major alpha-helix and beta-sheet is somewhat weakened, the C terminus of the major helix is largely intact but its N terminus is exposed and a major loop has been invaded by solvent.  相似文献   
6.
Summary Scarites occidentalis has 2n=41 (females 2n=42), n=19+X1X2Y. This multiple sex-chromosome system and other karyotypic characteristics suggest that this species andS. buparius share a recent common ancestor in which the sex trivalent was probably originated.Thanks are due to Dr N. Virkki for his valuable comments and his help with the English, to Dr Ramos and Dr Aparicio for discussion and advice, to Dr F. Hiraldo and M. Mañez for collecting the specimens. This work has been supported by a postdoctoral fellowship of the Consejo Superior de Investigaciones Científicas.  相似文献   
7.
L Serrano  J L Neira  J Sancho  A R Fersht 《Nature》1992,356(6368):453-455
The rational design of proteins requires knowledge of the helix-forming propensities (s-values) of the different amino acids. There is, however, considerable controversy about the relative values for alanine and glycine. We find from experiments on mutants of barnase that the relative effect of Ala versus Gly on helix stability depends crucially on the position in the helix (whether they are at the ends (caps) or are internal) and the context (the influence of their neighbours). Glycine is greatly preferred at the N and C caps. At internal positions, Ala stabilizes the helix relative to Gly by 0.4 to 2 kcal mol-1. The variation results from a combination of burial of hydrophobic surface on folding and interference with hydrogen bonding of the protein with solvent. There is a good empirical correlation between the relative stabilizing effects of Ala and Gly with the total change in solvent-accessible hydrophobic surface area of the folded protein on mutation of Gly to Ala. It is not valid to assign to each amino acid a unique s-value that is generally applicable to all positions in all helices in all proteins.  相似文献   
8.
Tumour biology: senescence in premalignant tumours   总被引:1,自引:0,他引:1  
Oncogene-induced senescence is a cellular response that may be crucial for protection against cancer development, but its investigation has so far been restricted to cultured cells that have been manipulated to overexpress an oncogene. Here we analyse tumours initiated by an endogenous oncogene, ras, and show that senescent cells exist in premalignant tumours but not in malignant ones. Senescence is therefore a defining feature of premalignant tumours that could prove valuable in the diagnosis and prognosis of cancer.  相似文献   
9.
Fasting (48 h) results in dopamine-beta-hydroxylase (DBH) release both in adrenal gland and spleen, suggestive of an increase in the activity of these organs. Cold exposure (48 h) produces a dissociation of the sympathoadrenal response. When both stimuli are simultaneously employed, the DBH response suggests the preponderance of the response to fasting. Plasma DBH is decreased in all groups studied, this could be due to its half-life and the splenic DBH depletion.  相似文献   
10.
Summary Fasting (48 h) results in dopamine-beta-hydroxylase (DBH) release both in adrenal gland and spleen, suggestive of an increase in the activity of these organs. Cold exposure (48 h) produces a dissociation of the, sympathoadrenal response. When both stimuli are simultaneously employed, the DBH response suggests the preponderance of the response to fasting. Plasma DBH is decreased in all groups studied, this could be due to its half-life and the splenic DBH depletion.This work was supported by a grant of Fondo de Investigaciones Sanitarias de la Seguridad Social, No. 83/0905.  相似文献   
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