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41.
Ahmed Imrul Mosaddek Nadira Umme Aktari Cao Fangbin He Xiaoyan Zhang Guoping Wu Feibo 《Planta》2016,243(4):973-985
Planta - The drought-stimulated gene expression of NCED, SUS, and KS - DHN and ABA signal cross-talk with other phytohormones maintains barley root growth under drought stress at pH 4.0 plus... 相似文献
42.
H. Elenga O. Peyron R. Bonnefille D. Jolly R. Cheddadi J. Guiot V. Andrieu S. Bottema G. Buchet J.-L. De Beaulieu A. C. Hamilton J. Maley R. Marchant R. Perez-Obiol M. Reille G. Riollet L. Scott H. Straka D. Taylor E. Van Campo A. Vincens F. Laarif H. Jonson 《Journal of Biogeography》2000,27(3):621-634
Pollen data from 18,000 14C yr bp were compiled in order to reconstruct biome distributions at the last glacial maximum in southern Europe and Africa. Biome reconstructions were made using the objective biomization method applied to pollen counts using a complete list of dryland taxa wherever possible. Consistent and major differences from present‐day biomes are shown. Forest and xerophytic woods/scrub were replaced by steppe, both in the Mediterranean region and in southern Africa, except in south‐western Cape Province where fynbos (xerophytic scrub) persisted. Sites in the tropical highlands, characterized today by evergreen forest, were dominated by steppe and/or xerophytic vegetation (cf. today’s Ericaceous belt and Afroalpine grassland) at the last glacial maximum. Available data from the tropical lowlands are sparse but suggest that the modern tropical rain forest was largely replaced by tropical seasonal forest while the modern seasonal or dry forests were encroached on by savanna or steppe. Montane forest elements descended to lower elevations than today. 相似文献
43.
44.
Zhenzhen Zhang Changjiu He Yu Gao Lu Zhang Yukun Song Tianqi Zhu Kuanfeng Zhu Dongying Lv Jing Wang Xiuzhi Tian Teng Ma Pengyun Ji Wei Cui Guoshi Liu 《Aging cell》2021,20(2)
The fecundity reduction with aging is referred as the reproductive aging which comes earlier than that of chronological aging. Since humans have postponed their childbearing age, to prolong the reproductive age becomes urgent agenda for reproductive biologists. In the current study, we examined the potential associations of α‐ketoglutarate (α‐KG) and reproductive aging in mammals including mice, swine, and humans. There is a clear tendency of reduced α‐KG level with aging in the follicle fluids of human. To explore the mechanisms, mice were selected as the convenient animal model. It is observed that a long term of α‐KG administration preserves the ovarian function, the quality and quantity of oocytes as well as the telomere maintaining system in mice. α‐KG suppresses ATP synthase and alterations of the energy metabolism trigger the nutritional sensors to down‐regulate mTOR pathway. These events not only benefit the general aging process but also maintain ovarian function and delay the reproductive decline. Considering the safety of the α‐KG as a naturally occurring molecule in energy metabolism, its utility in reproduction of large mammals including humans deserves further investigation. 相似文献
45.
Abstract This paper deals in detail with the morphology of the larva of Neopsylla specialis specialis Jordan, 1932. It may be distinguished from other larvae of 5 species or subspecies of Neopsylla by two fine setae lying on outside of each posterior long seta on the ventral plates of the first to third thoracic segments, ratio of the length and width of the egg burster, number and shape of mandibular teeth, number and length of the setae in the anterior and posterior row on dorsal side of head, and number of the setae of anal comb and the strut setae. The sense organs on the 10th tergite are discussed. 相似文献
46.
Sonia Coni Silvia Maria Serrao Zuleyha Nihan Yurtsever Laura Di Magno Rosa Bordone Camilla Bertani Valerio Licursi Zaira Ianniello Paola Infante Marta Moretti Marialaura Petroni Francesca Guerrieri Alessandro Fatica Alberto Macone Enrico De Smaele Lucia Di Marcotullio Giuseppe Giannini Marella Maroder Enzo Agostinelli Gianluca Canettieri 《Cell death & disease》2020,11(12)
47.
André De Troyer 《Journal of applied physiology》2005,98(3):795-803
Changes in intrathoracic pressure produced by the various inspiratory intercostals are essentially additive, but the interaction between these muscles and the diaphragm remains uncertain. In the present study, this interaction was assessed by measuring the changes in airway opening (DeltaPao) or transpulmonary pressure (DeltaPtp) in vagotomized, phrenicotomized dogs during spontaneous inspiration (isolated intercostal contraction), during isolated rectangular or ramp stimulation of the peripheral ends of the transected C(5) phrenic nerve roots (isolated diaphragm contraction), and during spontaneous inspiration with superimposed phrenic nerve stimulation (combined diaphragm-intercostal contraction). With the endotracheal tube occluded at functional residual capacity, DeltaPao during combined diaphragm-intercostal contraction was nearly equal to the sum of the DeltaPao produced by the two muscle groups contracting individually. However, when the endotracheal tube was kept open, DeltaPtp during combined contraction was 123% of the sum of the individual DeltaPtp (P < 0.001). The increase in lung volume during combined contraction was also 109% of the sum of the individual volume increases (P < 0.02). Abdominal pressure during combined contraction was invariably lower than during isolated diaphragm contraction. It is concluded, therefore, that the canine diaphragm and intercostal muscles act synergistically during lung expansion and that this synergism is primarily due to the fact that the intercostal muscles reduce shortening of the diaphragm. When the lung is maintained at functional residual capacity, however, the synergism is obscured because the greater stiffness of the rib cage during diaphragm contraction enhances the DeltaPao produced by the isolated diaphragm and reduces the DeltaPao produced by the intercostal muscles. 相似文献
48.
Lusinete Aciole De Queiroz 《Mycopathologia》1973,51(4):307-314
A new species of the genusEndomycopsis is proposed. It was isolated from waste water, at Montevideo-Uruguay.By its morphological and biochemical proprieties it differs from allEndomycopsis previously described.
Este trabajo fue desarrollado en el Laboratorio de Micologia de la Facultad de Química de Montevideo, Uruguay y en uso de una beca de la Universidad Federal de Pernambuco para perfecciobamiento en el estudio de las levaduras. 相似文献
Este trabajo fue desarrollado en el Laboratorio de Micologia de la Facultad de Química de Montevideo, Uruguay y en uso de una beca de la Universidad Federal de Pernambuco para perfecciobamiento en el estudio de las levaduras. 相似文献
49.
Isolation of Temperature-Sensitive Membrane Mutants of Escherichia coli K-12 总被引:1,自引:1,他引:0 下载免费PDF全文
Johan F. Steenbakkers J. H. F. F. Broekman A. Kerkenaar P. G. De Haan 《Journal of bacteriology》1973,116(2):535-540
Mutants with impaired biosynthesis of unsaturated fatty acids or altered metabolism of the phospholipids were isolated at a rather high frequency from a set of temperature-sensitive lysis mutants. It is suggested that preselection for the lysis phenotype makes it possible to isolate several kinds of mutants affected in the integrity of the cytoplasmic membrane. 相似文献
50.
Physiological and Biochemical Mechanisms Involved in the Response to Abscisic Acid in Maize Coleoptiles 总被引:2,自引:0,他引:2
The role of abscisic acid (ABA) in controlling growth and developmenthas been studied in maize (Zea mays L.) coleoptile segments.Application of ABA reduces the elongation rate by about 50%and affects ion fluxes. In particular, proton extrusion is decreasedwhile potassium efflux is greatly enhanced. Apparently, ABAdoes not: seem to influence calcium influx from the apoplastinto the cytosol, but more likely it influences its efflux.Alteration of cytosolic calcium concentration may also be obtainedby increasing its release from internal stores. This possibilitymight be sustained by the increased hydrolysis of phosphatidylinositolupon ABA application. Change in the balance of ion fluxes shouldresult from regulation of transport mechanisms at the membranelevel and should produce changes in the transmembrane electricalpotential. The H+- ATPase and the ATP-dependent calcium transportactivities are both influenced by the treatment with ABA, 55%and 40%, respectively. Under these conditions [Ca2+]cytand pHcyt can be modified and, as a consequence of their regulation,they may play an important role in mediating the physiologicaland biochemical effects of ABA, acting as second intracellularmessengers.
1Research supported by National Research Council of Italy, SpecialProject RAISA, Sub-Project N. 2, Paper n. 2782. 相似文献