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181.
Histological and physiological studies indicated that most skeletal muscles can be divided into a series of relatively independent sub-volumes: "neuromuscular compartments" and the partitioning property of the muscle result in the localization of muscle reflex. In the present experiment we studied the recruitment properties of medial gastracnemius (MG) muscle motoneuron pool of decerebrate cat with two kinds of local mechanical stimulation: local stretch and acupuncture-like stimuli. The results indicate that: (ⅰ) there is an obvious property of localization of recruitment activity, only the MNs which innervate the stimulated compartment were recruited by weaker and shorter stimuli; (ⅱ) recruitment activity spread to those MNs which supply the adjacent and distal compartments during the strength of stimulation or duration of the stimulation was increased; and (ⅲ) the recruitment property of muscle activity elicited by the local mechanical stimulation is thought similar to that of "needle feeling" along the meridian pathway during stimulation of acupuncture point.  相似文献   
182.
183.
An oxygen isotope temperature record from 381 to 166 kaB. P. (230Th/234U dating and tuned ages) has been obtained by combining data on the isotopic composition of calcites with that of fluid inclusions trapped in a stalagmite from a limestone cave in which a fossil cranium deposited. Several laminae in microsequence of the stalagmite represent climatic events or shifts. The Nanjing man fossil was older than 381 kaB. P.  相似文献   
184.
185.
An energy theory is proposed on the buckling of a ferromagnetic thin plate in a transverse static magnetic field. The analytic solution of critical field for plates is obtained by using variational method. It is shown that the critical magnetic field is not only influenced by the ratio of the thickness to the length, but also by the width, total length and the magnetic susceptibility of the specimen. Theoretical calculations agree with experiments reasonably.  相似文献   
186.
Colony-stimulating factor-1 (CSF-1), which is necessary for cell proliferation and differentiation, regulates both immediate and delayed early responses throughout G1 phase. The binding of CSF-1 to its receptor (CSF-1R) triggers phosphorylation of the receptor and its intrinsic tyrosine kinase. The activated receptor binds directly to cytoplasmic effector proteins, which induce multiple-signal transduction pathways. CSF-1 can induce the c-myc gene expression via Ras and Ets-related proteins. The expression of c-fos/jun family genes is also targeted following the activation of Ras. CSF-1R activates STAT1 and STAT3 to participate in signaling, but JAKs do not appear to contribute to signaling by CSF-1R. CSF-1R activates PI3-kinase, and PI3-ki can interact with downstream proteins by the MAPKK-related pathway independent of Ras/Raf. PC-PLC can enforce signaling in response to CSF-1. Furthermore, the turnover and dephosphorylation by the phosphatase SHPTP1 of CSF-1R are the major mechanism in the negative regulation of signaling by CSF-1R  相似文献   
187.
This is a report of carbon isotope anomaly in marbles associated with the UHP eclogites from the Dabie Mountains. The results place constraints on the degree of crust-mantle interaction during the UHP metamorphism.  相似文献   
188.
SrGa2S4: Ce blue TFEL device with a novel structure was prepared by electron beam evaporation. The dielectric constant of insulator layer in this structure is far less than that in the conventional structure, so the hot-electrons can be accelerated in SiO2 layers. The stable TFEL with good chromaticity was achieved and the basic characteristics were investigated.  相似文献   
189.
An all solid-state electrochromic smart window employing prussian blue and electrodeposited WO3 film with poly (vinyl chloride) (PVC) gel electrolyte that has high conductivity (2 mS/cm) at room temperature has been fabricated for the first time. The smart window has beell found to be excellent for electrochromism and memory characteristics.  相似文献   
190.
The plagioclase amphibolites from Kuokesu area, Kuruktag, Xinjiang occur as enclaves embedded in the granodioritic gneiss. In the light of major elements and REE data, the parent rocks of the plagioclase amphibolites belong to weak_alkaline basalts. Their Nd model ages mainly range from 2 832 to 3 075 Ma. The seven plagioclase amphibolites yield a reasonable good isochron age of (828±86) Ma(2σ) with I Nd =0.510 981±82, ε Nd ( t )=-11.5±1.6. Such a case shows the existence of great proportion of the Archaean mafic crustal basement on the Kuokesu area. The strong tectonic_thermal event at about 820 Ma made the Sm_Nd isotope of the metamorphic rocks homogenization. This event would be associated with the Tarim Movement.  相似文献   
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