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The reproduction of apterous virginoparae of A. fabae on field beans is primarily controlled by nutrition of both the larval and adult stages. The kind of hostplant and the lighting conditions under which it is grown affect the aphid's fecundity and reproductive rate. Plants grown under mercury fluorescent lamps provide the aphids with better or more nutrients of the right kind so that they reproduce better than aphids living on plants grown in daylight in glasshouses.Nutrition during larval life also affects the early reproductive rate and fecundity of the aphids. Aphids that grew quickly as larvae reproduced faster during early adult life than slow developers. Fast developers were heavier and larger but did not contain more embryos than slow developers as adults and probably received a more nutritious food supply during their larval lives.
Zusammenfassung Die Fortpflanzung ungeflügelter Virginoparer von Aphis fabae auf Ackerbohnen wird primär durch die Ernährung der Larven und Erwachsenen gesteuert. Die Art der Wirtspflanze und die Beleuchtungsbedingungen, unter denen sie sich entwickeln, beeinflussen die Gesamt-Fruchtbarkeit und die Reproduktionsrate der Blattläuse. Pflanzen, die unter Quecksilber-Fluoreszenz-Lampen (Leuchtstoffröhren) aufwuchsen, bieten den Blattläusen offensichtlich bessere oder mehr Nahrungsstoffe der erforderlichen Art, so daß sie sich besser fortpflanzen als Läuse, die auf Pflanzen leben, die im Gewächshaus unter Tageslicht aufgezogen wurden.Auch die Ernährungsverhältnisse während des Larvallebens beeinflussen die anfängliche Reproduktionsrate und die Fruchtbarkeit der Blattläuse. Manche Blattläuse, die sich rascher als andere entwickeln, hatten im frühen Adultstadium eine höhere Reproduktionsrate als die Langsam-Entwickler. Schnell-Entwickler waren schwerer und größer als Langsam-Entwickler und erhielten während ihres Larvallebens wahrscheinlich eine nahrhaftere Kost.相似文献
44.
Pedro A. Soares Jean A. Trejaut Teresa Rito Bruno Cavadas Catherine Hill Ken Khong Eng Maru Mormina Andreia Brandão Ross M. Fraser Tse-Yi Wang Jun-Hun Loo Christopher Snell Tsang-Ming Ko António Amorim Maria Pala Vincent Macaulay David Bulbeck James F. Wilson Leonor Gusmão Luísa Pereira Stephen Oppenheimer Marie Lin Martin B. Richards 《Human genetics》2016,135(3):309-326
45.
A Role for Protein Kinase Bβ/Akt2 in Insulin-Stimulated GLUT4 Translocation in Adipocytes 总被引:1,自引:0,他引:1
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Michelle M. Hill Sharon F. Clark David F. Tucker Morris J. Birnbaum David E. James S. Lance Macaulay 《Molecular and cellular biology》1999,19(11):7771-7781
Insulin stimulates glucose uptake into muscle and fat cells by promoting the translocation of glucose transporter 4 (GLUT4) to the cell surface. Phosphatidylinositide 3-kinase (PI3K) has been implicated in this process. However, the involvement of protein kinase B (PKB)/Akt, a downstream target of PI3K in regulation of GLUT4 translocation, has been controversial. Here we report that microinjection of a PKB substrate peptide or an antibody to PKB inhibited insulin-stimulated GLUT4 translocation to the plasma membrane by 66 or 56%, respectively. We further examined the activation of PKB isoforms following treatment of cells with insulin or platelet-derived growth factor (PDGF) and found that PKBbeta is preferentially expressed in both rat and 3T3-L1 adipocytes, whereas PKBalpha expression is down-regulated in 3T3-L1 adipocytes. A switch in growth factor response was also observed when 3T3-L1 fibroblasts were differentiated into adipocytes. While PDGF was more efficacious than insulin in stimulating PKB phosphorylation in fibroblasts, PDGF did not stimulate PKBbeta phosphorylation to any significant extent in adipocytes, as assessed by several methods. Moreover, insulin, but not PDGF, stimulated the translocation of PKBbeta to the plasma membrane and high-density microsome fractions of 3T3-L1 adipocytes. These results support a role for PKBbeta in insulin-stimulated glucose transport in adipocytes. 相似文献
46.
This paper identifies two difficulties with treatments of derivation in Algonquian languages. In traditional approaches to grammar, in which the morpheme is seen as a unitary entity, morphemes are understood as minimal units of meaning and/or function. Definitions share an appeal to the morpheme’s indivisibility. In the Algonquianist literature, in contrast, some morphemes (‘components’) can themselves contain other morphemes (which we call ‘formatives’) and they can also be synchronically derived from other components or stems. Drawing data from Menominee, we propose that these difficulties disappear if the formatives are seen as historical rather than synchronic units, while the components are the synchronic morphemes. Formatives bear the hallmarks of historical products of morphologization (phonetic/phonological reduction, semantic bleaching, and increase in grammatical function), and we conclude that they are not part of synchronic grammatical computation. This resolves problems present in traditional and modern theoretical approaches to Algonquian derivation, and has broader ramifications for linguistic theory: in both the structuralist and generativist traditions, synchronic grammar has often been seen as expansive, responsible for generating surface patterns that may instead be products of history. This has been the case in phonology and syntax. The present paper provides a study of the phenomenon in derivational morphology, and suggests that a more modest role for synchronic rules is called for. 相似文献
47.
J Klein J Gonzalez J Duchene L Esposito JP Pradère E Neau C Delage D Calise A Ahluwalia P Carayon JB Pesquero M Bader JP Schanstra JL Bascands 《FASEB journal》2009,23(1):134-142
Renal fibrosis is the common histological feature of advanced glomerular and tubulointerstitial disease leading to end-stage renal disease (ESRD). However, specific antifibrotic therapies to slow down the evolution to ESRD are still absent. Because persistent inflammation is a key event in the development of fibrosis, we hypothesized that the proinflammatory kinin B1 receptor (B1R) could be such a new target. Here we show that, in the unilateral ureteral obstruction model of renal fibrosis, the B1R is overexpressed and that delayed treatment with an orally active nonpeptide B1R antagonist blocks macrophage infiltration, leading to a reversal of the level of renal fibrosis. In vivo bone marrow transplantation studies as well as in vitro studies on renal cells show that part of this antifibrotic mechanism of B1R blockade involves a direct effect on resident renal cells by inhibiting chemokine CCL2 and CCL7 expression. These findings suggest that blocking the B1R is a promising antifibrotic therapy. 相似文献
48.
Background
DNA repair is the general term for the collection of critical mechanisms which repair many forms of DNA damage such as methylation or ionizing radiation. DNA repair has mainly been studied in experimental and clinical situations, and relatively few information-based approaches to new extracting DNA repair knowledge exist. As a first step, automatic detection of DNA repair proteins in genomes via informatics techniques is desirable; however, there are many forms of DNA repair and it is not a straightforward process to identify and classify repair proteins with a single optimal method. We perform a study of the ability of homology and machine learning-based methods to identify and classify DNA repair proteins, as well as scan vertebrate genomes for the presence of novel repair proteins. Combinations of primary sequence polypeptide frequency, secondary structure, and homology information are used as feature information for input to a Support Vector Machine (SVM). 相似文献49.
The authors report the rates of obesity, hypertension, hypercholesterolemia, smoking, and macrovascular and microvascular complications among Mohawks of Kahnawake, PQ, who have non-insulin-dependent diabetes mellitus. The data were derived from a study comparing rates of macrovascular and microvascular complications among the diabetic subjects and a nondiabetic group matched for age and sex. The data for both groups were collected by means of chart review, interview and body measurement. There were no important differences between the male and female diabetic subjects. Both sexes had high levels of obesity, hypertension, hypercholesterolemia and diabetic complications. A total of 86% of the diabetic subjects were obese; the rate was also very high (74%) among the nondiabetic subjects. The mean age at onset of diabetes, 59 years, was 10 years higher than that observed in Oneida Iroquois of Ontario. The rates of macrovascular disease among the diabetic subjects were higher than those found among Cree/Ojibwa in Ontario and Manitoba. Our findings add to the knowledge of non-insulin-dependent diabetes in North American Indians in Canada and show that there are differences between our Mohawk subjects and diabetic people of other native communities. 相似文献
50.
Single-Cell Multiomics: Multiple Measurements from Single Cells 总被引:1,自引:0,他引:1