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131.
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
132.
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. |
133.
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
134.
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
135.
Manfred Milinski 《Philosophical transactions of the Royal Society of London. Series B, Biological sciences》2016,371(1687)
Decision rules of reciprocity include ‘I help those who helped me’ (direct reciprocity) and ‘I help those who have helped others’ (indirect reciprocity), i.e. I help those who have a reputation to care for others. A person''s reputation is a score that members of a social group update whenever they see the person interacting or hear at best multiple gossip about the person''s social interactions. Reputation is the current standing the person has gained from previous investments or refusal of investments in helping others. Is he a good guy, can I trust him or should I better avoid him as a social partner? A good reputation pays off by attracting help from others, even from strangers or members from another group, if the recipient''s reputation is known. Any costly investment in others, i.e. direct help, donations to charity, investment in averting climate change, etc. increases a person''s reputation. I shall argue and illustrate with examples that a person''s known reputation functions like money that can be used whenever the person needs help. Whenever possible I will present tests of predictions of evolutionary theory, i.e. fitness maximizing strategies, mostly by economic experiments with humans. 相似文献
136.
137.
Luis Garreta Ivania CernSouza Manfred Ricardo Palacio Paula H. ReyesHerrera 《Ecology and evolution》2021,11(12):7411
The genome‐wide association studies (GWASs) are essential to determine the genetic bases of either ecological or economic phenotypic variation across individuals within populations of the model and nonmodel organisms. For this research question, the GWAS replication testing different parameters and models to validate the results'' reproducibility is common. However, straightforward methodologies that manage both replication and tetraploid data are still missing. To solve this problem, we designed the MultiGWAS, a tool that does GWAS for diploid and tetraploid organisms by executing in parallel four software packages, two designed for polyploid data (GWASpoly and SHEsis) and two designed for diploid data (GAPIT and TASSEL). MultiGWAS has several advantages. It runs either in the command line or in a graphical interface; it manages different genotype formats, including VCF. Moreover, it allows control for population structure, relatedness, and several quality control checks on genotype data. Besides, MultiGWAS can test for additive and dominant gene action models, and, through a proprietary scoring function, select the best model to report its associations. Finally, it generates several reports that facilitate identifying false associations from both the significant and the best‐ranked association Single Nucleotide Polymorphisms (SNPs) among the four software packages. We tested MultiGWAS with public tetraploid potato data for tuber shape and several simulated data under both additive and dominant models. These tests demonstrated that MultiGWAS is better at detecting reliable associations than using each of the four software packages individually. Moreover, the parallel analysis of polyploid and diploid software that only offers MultiGWAS demonstrates its utility in understanding the best genetic model behind the SNP association in tetraploid organisms. Therefore, MultiGWAS probed to be an excellent alternative for wrapping GWAS replication in diploid and tetraploid organisms in a single analysis environment. 相似文献
138.
Christina Bock Manfred Jensen Dominik Forster Sabina Marks Julia Nuy Roland Psenner Daniela Beisser Jens Boenigk 《Environmental microbiology》2020,22(6):2243-2260
Factors shaping community patterns of microorganisms are controversially discussed. Physical and chemical factors certainly limit the survival of individual taxa and maintenance of diversity. In recent years, a contribution of geographic distance and dispersal barriers to distribution patterns of protists and bacteria has been demonstrated. Organismic interactions such as competition, predation and mutualism further modify community structure and maintenance of distinct taxa. Here, we address the relative importance of these different factors in shaping protists and bacterial communities on a European scale using high-throughput sequencing data obtained from lentic freshwater ecosystems. We show that community patterns of protists are similar to those of bacteria. Our results indicate that cross-domain organismic factors are important variables with a higher influence on protists as compared with bacteria. Abiotic physical and chemical factors also contributed significantly to community patterns. The contribution of these latter factors was higher for bacteria, which may reflect a stronger biogeochemical coupling. The contribution of geographical distance was similar for both microbial groups. 相似文献
139.
Tserendorj Gegeensuvd Marinova Elena Lechterbeck Jutta Behling Hermann Wick Lucia Fischer Elske Sillmann Marion Märkle Tanja Rösch Manfred 《Vegetation History and Archaeobotany》2021,30(1):35-46
Vegetation History and Archaeobotany - A system of farming with an alternation of land use between being cultivated or left fallow as grassland (Feldgraswirtschaft) developed in southwestern... 相似文献
140.
Manfred Schartl Susanne Kneitz Jenny Ormanns Cornelia Schmidt Jennifer L. Anderson Angel Amores Julian Catchen Catherine Wilson Dietmar Geiger Kang Du Mateo Garcia-Olazábal Sudha Sudaram Christoph Winkler Rainer Hedrich Wesley C. Warren Ronald Walter Axel Meyer John H. Postlethwait 《Current biology : CB》2021,31(5):911-922.e4