The Bose Paleolithic industry in the Bose Basin, Guangxi, South China is well known in the international scientific community for its bearing handaxes dated back to 803 ka. Seven terraces were developed in the basin and terrace 4 is the most important because handaxes and tektites were recovered from this terrace. Since the first site was discovered in 1973, additional sites of the Bose Paleolithic industry have been investigated and excavated, most of which are located on terrace 4. The previous studies concluded that there is only one phase within this industry and its age is 803 ka. However, before 2013, no attempt had been made to dig down to the basal gravels from the top of terrace 4 in archaeological excavations. Therefore, the stratigraphy and the layers from which the stone artifacts derive of terrace 4 are not clear. In 2013–2014, we conducted an excavation of 200 m2 at the Gaolingpo site, which is one of the most important Paleolithic sites in the Bose Basin. We excavated to the basal gravel deposits from the top of this terrace, and a section of more than 7 meters thick deposit was exposed and clearly shows the stratigraphic layers of Pleistocene and Holocene deposits. Furthermore, features and about 800 stone artifacts including choppers, picks, scrapers, etc. were excavated from several stratigraphic layers, which are different in age and other aspects. Based on stratigraphy and the stone artifacts, three stages of Paleolithic cultural remains from the Gaolingpo site can be established. The first stage is in the age of at leat 803 ka. The second stage can be dated to 15 ka and the third stage to about 10 ka. 相似文献
Abrigo de la Quebrada offers an exceptional sequence with nine occupation levels which seven belongs to Middle Paleolithic. The division between levels II to V and VII to IX by a sterile level VI allow us to study diachronic changes on raw materials and knapping systems. This data is compared with other contemporary sites to evaluate technological trends and the raw material availability in the central region of Mediterranean area. 相似文献
A truncated Man9-mannosidase gene and a full-length -1,4-galactosyltransferase gene were isolated from human kidney and placenta cDNAs, respectively. Both genes were cloned in plasmid pMAL-c2 to produce fusions with maltose-binding protein. Fusion products were purified by affinity chromatography. Purified enzymes were assayed using pyridyl-amino labelled oligosaccharides as substrates and analysed by HPLC. 相似文献
1. 1.Effects of habitat on the thermal regime were investigated in two diurno—nocturnal geckos in Hawaii.
2. 2.In trees Hemidactylus frenatus thermoregulated in daytime with body temperature (BT) above air temperture (AT); in houses some thermoregulated likewise in daytime but mainly the species thermoregulated at night, on electric lamps, to the same BT as in trees by day.
3. 3.Lepidodactylus lugubris in trees thermoregulated in daytime, its BT lower than in H. frenatus. In the rocks it had at night a BT resembling that in trees in daytime, because the thermal cycle in rock crevices lagged behind outside AT.
4. 4.The flexibility of these geckos in thermal regime and activity cycle preadapts them to both migration and invasion of houses.
Author Keywords: Thermoregulation; thermal regime; diel activity cycle; body temperature; temperature regulation; Hemidactylus frenatus; Lepidodactylus lugubris; Gekkonidae; geckos; lizards; reptiles; Hawaii; migration; invasion of habitats; commensalism; lizards with man; activity; diurno—nocturnal; basking; rocks; thermal cycle; habitat, effects on thermoregulation; preadaptation 相似文献
Several extensive reviews concerning the actions of new positive inotropic agents in the treatment of congestive heart failure, often with reference to their mechanism of action, have recently been published [1–7]. Each of them has presented specific points of view. This review will place special emphasis on the significance of intracellular sodium activity for the modulation of myocardial inotropy; the continuing importance, after a 200 year history, of the use of cardiac glycosides as strong inotropic agents; the emerging significance of the phosphoinositide (PIP2) pathway to provide additional second messengers for the modulation and regulation of cardiac inotropy; the contribution of the 1-adrenergic system to cardiac inotropy; the increasing awareness of the significant involvement of adenosine and its antagonists in cardiac function; and the increasing realization that myocardial tissues are not homogeneous, i.e., that in many species the atrial and ventricular tissues are using different, even opposite mechanisms in the generation of their functional responses. 相似文献
Summary The mitogenic and differentiation-inducing activities of epidermal growth factor (EGF) in epithelial tissues have been well described. Since non-mitogenic effects of EGF, especially in mesenchymal tissues such as smooth muscle are not well-known (Nanney et al. 1984), we have examined EGF-binding and receptors in smooth muscle from many sites. Specific EGF binding sites were detected by incubating small pieces of tissue with 125I-EGF; immunoreactive EGF receptors were detected by immunohistochemistry. In-situ localization of 125I-EGF binding sites and immunoreactive EGF receptors of smooth muscle cells in intact mammalian tissues were identical using either 125I-EGF autoradiography or anti-EGF receptor antibody in an immunoperoxidase method. Cultured rat aortic smooth muscle also contained specific EGF receptors as detected by their biological response to EGF-binding and internalization of 125I-EGF, as well as EGF-stimulated phosphorylation of a 170K protein. The presence of EGF receptors in a well-differentiated smooth muscle cell indicates that EGF may play a physiological, but non-mitogenic role in mammalian tissues in vivo. 相似文献