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61.
Helmut Ponta Karl-Heinz Altendorf Manfred Schweiger Monica Hirsch-Kaufmann Mei-Li Pfennig-Yeh Peter Herrlich 《Molecular & general genetics : MGG》1976,149(2):145-150
Summary Infection of E. coli with the viruses T7 or T3 leads to a dramatic efflux of potassium ions. This ion efflux is caused by the virus particle since no concomitant protein synthesis is required. T7 mutants carrying deletions in the M-gene (Schweiger et al., 1975), however, yield virus particles disturbed in the ion release. 相似文献
62.
Growing lily (Lilium longiflorum Thunb.) pollen always drive a current into their tubes and out of their grains. The only external ions needed for growth (and the growth current) are K+, H+, and Ca2+. Increases in K+ immediately stimulate the current; while decreases in K+ immediately inhibit it. Comparable changes in H+ have the opposite effect; while those in Ca2+ have very little effect. We infer that most of the steady growth current is carried in by a potassium leak and out by a proton pump; but other considerations indicate that a minor, but controlling, component of the inward current consists of calcium ions. 相似文献
63.
Summary A deficient G-6PD variant was discovered in 4 males of one family from north-western Germany. Five generations of this family could be studied.The deficient G-6PD was a new variant, called Gd (-) Aachen. Its main characteristics are the following: severe enzyme deficiency in erythrocytes (3% of normal), contrasting with an almost normal activity in leukocytes; normal molecular specific activity (i.e., normal ratio enzyme activity/cross-reacting material); slow mobility in starch gel electrophoresis (92–94% of normal); increased Michaelis constant for glucose-6-phosphate (60–70 M) and NADP+ (20–25 M); decreased inhibition constant by NADPH with respect to NADP+ (7 M); increased inhibition by ATP; normal utilization of the substrate analogues; slightly biphasic pH curve; thermal instability, and normal activation energy of the enzymatic reaction.The relationships between the hematologic disorders (severe and frequent hemolytic crises) and the unfavorable kinetic modifications are discussed.with the technical assistance of Joelle Marie and Dominique CottreauDedicated to Prof. Dr. H. Schonenberg, Aachen, on his 60th birthday. The first results of this work were presented in part at the Kongress der Deutschen Kinderärzte, München. 相似文献
64.
Peter Schneider Manfred Hermes 《Journal of comparative physiology. A, Neuroethology, sensory, neural, and behavioral physiology》1976,106(1):39-49
The function of the flapping elytra was investigated in garden shafers (Melolontha melolontha L.) and rhinoceros beetles (Oryctes boas Fabr.).
相似文献
1. | The movements of alae and elytra are determined. Both move with the same frequency and in the same phase, but the range of the elytral stroke never reaches below the frontal plane. In downstroke the elytra are at an angle positive to the airstream (horizontal flight). |
2. | After exact investigation of the construction of the elytra (depth, width, length, surface, torsion and velocity of each point of the elytra) the most effective point in the production of lift during the downstroke was determined. |
3. | After loss of one third of the surface of the elytra the beetles cannot fly horizontally. In tethered flight the wing stroke frequency of the alae does not increase when the elytra are shortened. Shortening of the elytra does not interfere with the resonance system of the pterothorax. |
4. | The lift of the elytra results from active and passive components (more than 17% of the body weight). In the airstream (front 2.00 m/s, average body weight 944 mp) the passive lift is 14.3% for elytra in the down position; 3.1% of the lift is caused by the active downstroke. |
5. | The elytra of these beetles are indispensible for horizontal flight. Primarily they produce lift passively with added help from the downstroke, and have no function for the drag. The effect of upstroke is discussed. |
65.
Veronica lycica
Lehm. is a distinct, diploid member of theVeronica cymbalaria group, endemic in Lycia (S.W. Anatolia). Closely related is the newV. stamatiadae
M. Fischer etW. Greuter which is also diploid and seems to be restricted to the small Greek island Ro close to the South coast of Lycia. The chromosome numbers for both species are reported for the first time (2n = 18).
Untersuchungen über den PolyploidkomplexVeronica cymbalaria agg., II. — Der erste Beitrag dieser Serie:Fischer (1975). 相似文献
66.
Prof. Dr. Manfred Gersch Heiner Birkenbeil Joachim Ude 《Cell and tissue research》1975,160(3):389-397
The prothoracic glands of the last instar of Galleria mellonella undergo characteristic alterations of their cellular fine structure closely related to cellular activity. During progressive secretory activity of the gland cells there are extensive plasmalemmal infoldings and formation of a pronounced lacunar system. Mitochondria of the active cell phase are characterized by a specific increase in size and paler colour of the matrix. In contrast to the alterations, nuclei, ER and Golgi cisterns do not undergo any submicroscopic changes during the different phases of cellular activity. The relationship between the substructural phenomena and the specific phases of cellular activity are discussed. 相似文献
67.
Gap junction remodeling and altered connexin43 expression in the failing human heart 总被引:15,自引:0,他引:15
Kostin S Rieger M Dammer S Hein S Richter M Klövekorn WP Bauer EP Schaper J 《Molecular and cellular biochemistry》2003,242(1-2):135-144
Gap junctions (GJ) are important determinants of cardiac conduction and the evidence has recently emerged that altered distribution of these junctions and changes in the expression of their constituent connexins (Cx) may lead to abnormal coupling between cardiomyocytes and likely contribute to arrhythmogenesis. However, it is largely unknown whether changes in the expression and distribution of the major cardiac GJ protein, Cx43, is a general feature of diverse chronic myocardial diseases or is confined to some particular pathophysiological settings. In the present study, we therefore set out to investigate qualitatively and quantitatively the distribution and expression of Cx43 in normal human myocardium and in patients with dilated (DCM), ischemic (ICM), and inflammatory cardiomyopathies (MYO). Left ventricular tissue samples were obtained at the time of cardiac transplantation and investigated with immunoconfocal and electron microscopy. As compared with the control group, Cx43 labeling in myocytes bordering regions of healed myocardial infarction (ICM), small areas of replacement fibrosis (DCM) and myocardial inflammation (MYO) was found to be highly disrupted instead of being confined to the intercalated discs. In all groups, myocardium distant from these regions showed an apparently normal Cx43 distribution at the intercalated discs. Quantitative immunoconfocal analyis of Cx43 in the latter myocytes revealed that the Cx43 area per myocyte area or per myocyte volume is significantly decreased by respectively 30 and 55% in DCM, 23 and 48% in ICM, and by 21 and 40% in MYO as compared with normal human myocardium. In conclusion, focal disorganization of GJ distribution and down-regulation of Cx43 are typical features of myocardial remodeling that may play an important role in the development of an arrhythmogenic substrate in human cardiomyopathies. 相似文献
68.
Transcriptome profiling of immune tissues reveals habitat‐specific gene expression between lake and river sticklebacks 下载免费PDF全文
69.
Jacob Fry Manfred Lenzen Damien Giurco Stefan Pauliuk 《Journal of Industrial Ecology》2016,20(6):1295-1305
The production of waste creates both direct and indirect environmental impacts. A range of strategies are available to reduce the generation of waste by industry and households, and to select waste treatment approaches that minimize environmental harm. However, evaluating these strategies requires reliable and detailed data on waste production and treatment. Unfortunately, published Australian waste data are typically highly aggregated, published by a variety of entities in different formats, and do not form a complete time‐series. We demonstrate a technique for constructing a multi‐regional waste supply‐use (MRWSU) framework for Australia using information from numerous waste data sources. This is the first MRWSU framework to be constructed (to the authors' knowledge) and the first sub‐national waste input‐output framework to be constructed for Australia. We construct the framework using the Industrial Ecology Virtual Laboratory (IELab), a cloud‐hosted computational platform for building Australian multi‐regional input‐output tables. The structure of the framework complies with the System of Environmental‐Economic Accounting (SEEA). We demonstrate the use of the MRWSU framework by calculating waste footprints that enumerate the full supply chain waste production for Australian consumers. 相似文献
70.
Genetic sex determination in an XX-XY chromosome system can be realized through a locus on the Y chromosome that makes the undifferentiated gonad develop into a testis. Although this mechanism is widespread, only in two cases so far have the corresponding master male sex-determining genes been identified. One is Sry, which initiates testes determination in most mammals. The other is dmrt1bY (syn. dmy), from the fish medaka, Oryzias latipes. The mammalian Y is roughly estimated to be over 200 million years old. The medaka Y may be considerably younger. A comparative analysis of the genus Oryzias revealed that one sister species of the medaka has dmrt1bY on a homologous Y chromosome, whereas in another closely related species only a non-sex-linked pseudogene is present. In all other species, dmrt1bY was not detected. The divergence time for the different species was determined with mitochondrial DNA sequences. The timing was confirmed by independent calculations based on dmrt1 sequences. We show that the medaka sex-determining gene originated approximately 10 million years ago. This makes dmrt1bY and the corresponding Y chromosome the youngest male sex-determining system, at least in vertebrates, known so far. 相似文献