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1.
ABSTRACTThe article presents the analytical framework, notably Bateson’s concepts of the double-bind and flexibility, in the context of a discussion of the Anthropocene, and outlines the subsequent articles and their internal relationships. 相似文献
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Gordon H. Snow 《The Western journal of medicine》1964,101(4):260-262
The term “whiplash,” used to describe a neck injury received in an automobile accident, has no foundation in medical science to support the complaints of persons suing for damages. The term is gaining unwarranted popularity as a term describing an injury, even though there are no clinical or pathological findings to support it.“Whiplash” cases today account for an estimated 30 per cent of all injuries in automobile accidents. Direct compensation for damages paid to persons injured in automobile accidents in the United States in 1961 amounted to approximately one billion, seven hundred million dollars. It has been estimated that five hundred and eighty million dollars of that amount was paid in compensation on allegation of neck injuries. 相似文献
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Background
Economic growth is widely perceived as a major policy instrument in reducing childhood undernutrition in India. We assessed the association between changes in state per capita income and the risk of undernutrition among children in India.Methods and Findings
Data for this analysis came from three cross-sectional waves of the National Family Health Survey (NFHS) conducted in 1992–93, 1998–99, and 2005–06 in India. The sample sizes in the three waves were 33,816, 30,383, and 28,876 children, respectively. After excluding observations missing on the child anthropometric measures and the independent variables included in the study, the analytic sample size was 28,066, 26,121, and 23,139, respectively, with a pooled sample size of 77,326 children. The proportion of missing data was 12%–20%. The outcomes were underweight, stunting, and wasting, defined as more than two standard deviations below the World Health Organization–determined median scores by age and gender. We also examined severe underweight, severe stunting, and severe wasting. The main exposure of interest was per capita income at the state level at each survey period measured as per capita net state domestic product measured in 2008 prices. We estimated fixed and random effects logistic models that accounted for the clustering of the data. In models that did not account for survey-period effects, there appeared to be an inverse association between state economic growth and risk of undernutrition among children. However, in models accounting for data structure related to repeated cross-sectional design through survey period effects, state economic growth was not associated with the risk of underweight (OR 1.01, 95% CI 0.98, 1.04), stunting (OR 1.02, 95% CI 0.99, 1.05), and wasting (OR 0.99, 95% CI 0.96, 1.02). Adjustment for demographic and socioeconomic covariates did not alter these estimates. Similar patterns were observed for severe undernutrition outcomes.Conclusions
We failed to find consistent evidence that economic growth leads to reduction in childhood undernutrition in India. Direct investments in appropriate health interventions may be necessary to reduce childhood undernutrition in India. Please see later in the article for the Editors'' Summary 相似文献4.
Li-Qun Chen De Ye 《植物学报(英文版)》2007,49(1):94-98
Elongation of the pollen tube in pistil is essential for delivering sperms into the female gametophyte in sexual plant reproduction. Recently, a group of cell wall enzymes, pectin methylesterases (PMEs), have been identified as playing an important role in this process. This article reviews the new understanding of the roles of PMEs in regulating pollen tube growth. 相似文献
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Federica Accornero Jop H. van Berlo Robert N. Correll John W. Elrod Michelle A. Sargent Allen York Joseph E. Rabinowitz Andrew Leask Jeffery D. Molkentin 《Molecular and cellular biology》2015,35(12):2154-2164
The matricellular secreted protein connective tissue growth factor (CTGF) is upregulated in response to cardiac injury or with transforming growth factor β (TGF-β) stimulation, where it has been suggested to function as a fibrotic effector. Here we generated transgenic mice with inducible heart-specific CTGF overexpression, mice with heart-specific expression of an activated TGF-β mutant protein, mice with heart-specific deletion of Ctgf, and mice in which Ctgf was also deleted from fibroblasts in the heart. Remarkably, neither gain nor loss of CTGF in the heart affected cardiac pathology and propensity toward early lethality due to TGF-β overactivation in the heart. Also, neither heart-specific Ctgf deletion nor CTGF overexpression altered cardiac remodeling and function with aging or after multiple acute stress stimuli. Cardiac fibrosis was also unchanged by modulation of CTGF levels in the heart with aging, pressure overload, agonist infusion, or TGF-β overexpression. However, CTGF mildly altered the overall cardiac response to TGF-β when pressure overload stimulation was applied. CTGF has been proposed to function as a critical TGF-β effector in underlying tissue remodeling and fibrosis throughout the body, although our results suggest that CTGF is of minimal importance and is an unlikely therapeutic vantage point for the heart. 相似文献
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Two kinds of α-galactosidase-producing microorganisms, strain No. 31–2 and strain No. 7–5, have been isolated from soil and subjected to a determinative study. On the basis of the morphological and physiological characters, the strain No. 31–2 was identified to be belonged to genus Micrococcus and the strain No. 7–5 to genus Bacillus. The former strain, Micrococcus sp. No. 31–2, produced exclusively an intracellular α-galactosidase, and the latter one, Bacillus sp. No. 7–5, secreted the enzyme into culture medium. The cell growth and enzyme production of both strains were observed to reach the maximum under an alkaline culture condition. The intracellular α-galactosidase of Micrococcus sp. No. 31–2 was inducible by galactose, melibiose, and raffinose, while the α-galactosidase of Bacillus sp. No. 7–5 was produced constitutively. 相似文献
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Yusuke Suzuki Makoto Yanagisawa Hirokazu Yagi Yoshihiko Nakatani Robert K. Yu 《The Journal of biological chemistry》2010,285(24):18443-18451
In neural stem cells, basic fibroblast growth factor (bFGF) and epidermal growth factor (EGF) promote cell proliferation and self-renewal. In the bFGF- and EGF-responsive neural stem cells, β1-integrin also plays important roles in crucial cellular processes, including proliferation, migration, and apoptosis. The cross-talk of the signaling pathways mediated by these growth factors and β1-integrin, however, has not been fully elucidated. Here we report a novel molecular mechanism through which bFGF or EGF promotes the proliferation of mouse neuroepithelial cells (NECs). In the NECs, total β1-integrin expression levels and proliferation were dose-dependently increased by bFGF but not by EGF. EGF rather than bFGF strongly induced the increase of β1-integrin localization on the NEC surface. bFGF- and EGF-induced β1-integrin up-regulation and proliferation were inhibited after treatment with a mitogen-activated protein kinase kinase inhibitor, U0126, which indicates the dependence on the mitogen-activated protein kinase pathway. Involvement of β1-integrin in bFGF- and EGF-induced proliferation was confirmed by the finding that NEC proliferation and adhesion to fibronectin-coated dishes were inhibited by knockdown of β1-integrin using small interfering RNA. On the other hand, apoptosis was induced in NECs treated with RGD peptide, a small β1-integrin inhibitor peptide with the Arg-Gly-Asp motif, but it was independent of β1-integrin expression levels. Those results suggest that regulation of β1-integrin expression/localization is involved in cellular processes, such as proliferation, induced by bFGF and EGF in NECs. The mechanism underlying the proliferation through β1-integrin would not be expected to be completely identical, however, for bFGF and EGF. 相似文献
8.
Isolation and Growth Characteristics of an EDTA-degrading Member of the α-subclass of Proteobacteria
A Gram-negative, ethylenediaminetetraacetic acid (EDTA)-degrading bacterium (deposited at the German Culture Collection as strain DSM 9103) utilising EDTA as the only source of carbon, energy and nitrogen was isolated from a mixed EDTA-degrading population that was originally enriched in a column system from a mixture of activated sludge and soil. Chemotaxonomic analysis of quinones, polar lipids and fatty acids allowed allocation of the isolate to the alpha-subclass of Proteobacteria. 16S rDNA sequencing and phylogenetic analysis revealed highest similarity to the Mesorhizobium genus followed by the Aminobacter genus. However, the EDTA-degrading strain apparently forms a new branch within the Phyllobacteriaceae/Mesorhizobia family. Growth of the strain was rather slow not only on EDTA (micro(max) = 0.05 h(-1)) but also on other substrates. Classical substrate utilisation testing in batch culture suggested a quite restricted carbon source spectrum with only lactate, glutamate, and complexing agents chemically related to EDTA (nitrilotriacetate, iminodiacetate and ethylenediaminedisuccinate) supporting growth. However, when EDTA-limited continuous cultures of strain DSM 9103 were pulsed with fumarate, succinate, glucose or acetate, these substrates were assimilated immediately. Apparently, the strain can use a broader spectrum than indicated by traditional substrate testing techniques. The EDTA species CaEDTA and MgEDTA served as growth substrates of the strain because in the mineral medium employed EDTA was predicted to be mainly present in the form of these two complexes. The bacterium was not able to degrade Fe3+-complexed EDTA. 相似文献
9.
The authors have succeeded in isolating an antibiotic, from the cultured filtrate of Asp. oryzae, responsible for, at least, the majority of the active substances against hiochi-bacteria, as pale yellow crystals of m.p. 152~153°C. It has been proved that this antibiotic is identical with hydroxyaspergillic acid. The minimum concentration for complete inhibition in diluted Saké-peptone medium against true hiochi-bacilli, Lactobacillus homohiochii H-42 and Lactobacillus heterohiochii H-l, was 10 γ/ml, and that against hiochi-lactobacilli H-7 and H-34 20 γ/ml. 相似文献
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To test whether plant growth–promoting bacteria might be useful in facilitating the growth of Phragmites australis, the common reed, in the presence of metals and organic compounds, P. australis seeds were treated with plant growth–promoting bacteria. The bacterium Pseudomonas asplenii AC was genetically transformed to express a bacterial gene encoding the enzyme 1-aminocyclopropane-1-carboxylate deaminase,
and both the native and transformed bacteria were tested in conjunction with P. australis. Inoculation of seeds, which were subsequently grown in the presence of copper or creosote, with transformed P. asplenii AC significantly increased seed germination. Moreover, the addition of either native or transformed P. asplenii AC to P. australis seeds enabled the plants (shoots and roots) to attain a greater size than noninoculated plants after growth in soil in the
presence of either copper or creosote. 相似文献
14.
Werner Schlegel Adalbert Raimann Daniel Halbauer Daniela Scharmer Susanne Sagmeister Barbara Wessner Magdalena Helmreich Gabriele Haeusler Monika Egerbacher 《PloS one》2013,8(10)
Human insulin-like growth factor 1 Ec (IGF-1Ec), also called mechano growth factor (MGF), is a splice variant of insulin-like growth factor 1 (IGF-1), which has been shown in vitro as well as in vivo to induce growth and hypertrophy in mechanically stimulated or damaged muscle. Growth, hypertrophy and responses to mechanical stimulation are important reactions of cartilaginous tissues, especially those in growth plates. Therefore, we wanted to ascertain if MGF is expressed in growth plate cartilage and if it influences proliferation of chondrocytes, as it does in musculoskeletal tissues. MGF expression was analyzed in growth plate and control tissue samples from piglets aged 3 to 6 weeks. Furthermore, growth plate chondrocyte cell culture was used to evaluate the effects of the MGF peptide on proliferation. We showed that MGF is expressed in considerable amounts in the tissues evaluated. We found the MGF peptide to be primarily located in the cytoplasm, and in some instances, it was also found in the nucleus of the cells. Addition of MGF peptides was not associated with growth plate chondrocyte proliferation. 相似文献
15.
Pim Van Hoek Johannes P. Van Dijken Jack T. Pronk 《Applied and environmental microbiology》1998,64(11):4226-4233
The specific growth rate is a key control parameter in the industrial production of baker’s yeast. Nevertheless, quantitative data describing its effect on fermentative capacity are not available from the literature. In this study, the effect of the specific growth rate on the physiology and fermentative capacity of an industrial Saccharomyces cerevisiae strain in aerobic, glucose-limited chemostat cultures was investigated. At specific growth rates (dilution rates, D) below 0.28 h−1, glucose metabolism was fully respiratory. Above this dilution rate, respirofermentative metabolism set in, with ethanol production rates of up to 14 mmol of ethanol · g of biomass−1 · h−1 at D = 0.40 h−1. A substantial fermentative capacity (assayed offline as ethanol production rate under anaerobic conditions) was found in cultures in which no ethanol was detectable (D < 0.28 h−1). This fermentative capacity increased with increasing dilution rates, from 10.0 mmol of ethanol · g of dry yeast biomass−1 · h−1 at D = 0.025 h−1 to 20.5 mmol of ethanol · g of dry yeast biomass−1 · h−1 at D = 0.28 h−1. At even higher dilution rates, the fermentative capacity showed only a small further increase, up to 22.0 mmol of ethanol · g of dry yeast biomass−1 · h−1 at D = 0.40 h−1. The activities of all glycolytic enzymes, pyruvate decarboxylase, and alcohol dehydrogenase were determined in cell extracts. Only the in vitro activities of pyruvate decarboxylase and phosphofructokinase showed a clear positive correlation with fermentative capacity. These enzymes are interesting targets for overexpression in attempts to improve the fermentative capacity of aerobic cultures grown at low specific growth rates.The quality of commercial baker’s yeast (Saccharomyces cerevisiae) is determined by many parameters, including storage stability, osmotolerance, freeze-thaw resistance, rehydration resistance of dried yeast, and color. In view of the primary role of baker’s yeast in dough, fermentative capacity (i.e., the specific rate of carbon dioxide production by yeast upon its introduction into dough) is a particularly important parameter (2).In S. cerevisiae, high sugar concentrations and high specific growth rates trigger alcoholic fermentation, even under fully aerobic conditions (6, 18). Alcoholic fermentation during the industrial production of baker’s yeast is highly undesirable, as it reduces the biomass yield on the carbohydrate feedstock. Industrial baker’s yeast production is therefore performed in aerobic, sugar-limited fed-batch cultures. The conditions in such cultures differ drastically from those in the dough environment, which is anaerobic and with sugars at least initially present in excess (23).Optimization of biomass productivity requires that the specific growth rate and biomass yield in the fed-batch process be as high as possible. In the early stage of the process, the maximum feasible growth rate is dictated by the threshold specific growth rate at which respirofermentative metabolism sets in. In later stages, the specific growth rate is decreased to avoid problems with the limited oxygen transfer and/or cooling capacity of industrial bioreactors (10, 27). The actual growth rate profile during fed-batch cultivation is controlled primarily by the feed rate profile of the carbohydrate feedstock (4, 22). Generally, an initial exponential feed phase is followed by phases with constant and declining feed rates, respectively (8).From a theoretical point of view, the objective of suppressing alcoholic fermentation during the production phase may interfere with the aim of obtaining a high fermentative capacity in the final product. Process optimization has so far been based on strain selection and on empirical optimization of environmental conditions during fed-batch cultivation (e.g., pH, temperature, aeration rate, and feed profiles of sugar, nitrogen, and phosphorus [5, 10, 23]). For rational optimization of the specific growth rate profile, knowledge of the relation between specific growth rate and fermentative capacity is of primary importance. Nevertheless, quantitative data on this subject cannot be found in the literature.The chemostat cultivation system allows manipulation of the specific growth rate (which is equal to the dilution rate) while keeping other important growth conditions constant. Similar to industrial fed-batch cultivation, sugar-limited chemostat cultivation allows fully respiratory growth of S. cerevisiae on sugars (21, 37, 39). This is not possible in batch cultures, which by definition require high sugar concentrations, which lead to alcoholic fermentation, even during aerobic growth (6, 18, 37). Thus, as an experimental system, batch cultures bear little resemblance to the aerobic baker’s yeast production process. Indeed, we have recently shown that differences in fermentative capacity between a laboratory strain of S. cerevisiae and an industrial strain became apparent only in glucose-limited chemostat cultures but not in batch cultures (30).The aim of the present study was to assess the effect of specific growth rate on fermentative capacity in an industrial baker’s yeast strain grown in aerobic, sugar-limited chemostat cultures. Furthermore, the effect of specific growth rate on in vitro activities of key glycolytic and fermentative enzymes was investigated in an attempt to identify correlations between fermentative capacity and enzyme levels. 相似文献
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Roberto F. Escamilla John J. Hutchings Choh Hao Li Peter Forsham 《The Western journal of medicine》1966,105(2):104-110
Two male patients with achondroplastic dwarfism aged 7-5/12 and 14½ years were treated with human growth hormone 5 mg daily. Both showed nitrogen retention on balance studies, the older second patient to a marked degree. In the younger patient, height increased from 95.4 to 106.3 cm on hgh 5 mg daily alone for 14 out of 24 months. The rate of growth approximately doubled during the first two treatment periods as compared with the pre-treatment rate. In the second older patient hgh was administered 5 mg daily intramuscularly for 21 out of 33 months. Growth from 129.6 cm to 137.8 cm occurred with the rate increasing following the addition of Na-1-thyroxine to the routine. This increased growth rate occurred during the post-puberty deceleration phase. Bone ages, interpreted from changes in the phalanges and metacarpals, increased from 4½ to 6 years during 16 months in Case 1, and from 13½ to 18 years in 33 months in Case 2. Transient adolescent gynecomastia appeared in Case 2. No local or general toxic effects were noted.These results are suggestive, but whether or not the eventual height of an achondroplastic dwarf can be significantly altered must await further studies. 相似文献
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The authors give a sketch about the "K?rmend Growth Study" which is series of cross-sectional growth studies, carried out in K?rmend, a small town in Western Hungary. The first investigation was carried out in 1958 (K-58) and it has been repeated every ten years (K-68, K-78, K-88, and K-98). All 3-18 year-old healthy boys and girls in nurseries and schools in K?rmend were involved in the study. Twenty-three body measurements were taken. This paper focuses on changes in height, weight, and BMI. Means of these two body measurements show an increase from time to time (as a phenomenon of positive secular trend), however, the secular trend for increasing height and weight is declining. BMI follows a similar pattern. 相似文献
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Antagonism of Transforming Growth Factor-Β Signaling Inhibits
Fibrosis-Related Genes 总被引:4,自引:0,他引:4
In the fibrotic process, the transforming growth factor-β1 (TGF-β1)/Smad3 (Sma- and Mad-related protein␣3) signaling plays
a central role. To screen for antagonists of TGF-β1/Smad3 signaling and to investigate their effects on the genes related
to fibrosis, we construct a molecular model with a luciferase reporter gene. Results showed that both SB-431542 [4-(5-benzo[1,3]dioxol-5-yl-4-pyridin-2-yl-1H-imidazol-2-yl)-benzamide] and small interference RNA (siRNA) against Smad3 could dose-dependently suppress the reporter gene.
More importantly, they both significantly inhibited the expression of plasminogen activator inhibitor-type 1 (PAI-1) and type
I collagenα1 (Col Iα1) genes in rat hepatic stellate cells. Thus, SB-431542 and Smad3/siRNA may be potential therapeutics
for fibrosis. 相似文献