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121.
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Homogenates of tissue from the female genital tract contain isoamylases which are, to a certain extent, electrophoretically distinguishable from the pancreatic and salivary isoamylases. In healthy nonpregnant women, high levels of activity of genital isoamylases were found in tissue homogenates of cervical and Fallopian tube mucosa, whereas activity was weak or absent in homogenates of endometrium. The isoamylases of the cervical mucosa had an electrophoretic migration rate toward the anode identical to that of the salivary main fraction, whereas the isoamylases of the Fallopian tube migrated faster. Specific genital isoamylase activities were also demonstrable in peritoneal fluid collected from the cul-de-sac. During the menstrual cycle, these activities showed a midcycle peak. In pregnant women, the levels of activity of the genital isoamylases in peritoneal fluid were lower than in nonpregnant women. In homogenates of the male accessory genital glands, the isoamylases specific for the genital tract were present in minute amounts. The isoamylases specific for the genital tract were not detectable in serum in either sex. 相似文献
123.
Golgi and electron microscopic analysis of the known cellular layers in concentric shells of the ventro-lateral portion of the medial geniculate body revealed a flat grid of high density neuropil filling the space between the geniculocortical relay cells, forming essentially a single cell layer in each lamina. The "skeleton" of this neuropil grid is made up by the interdigitating dendritic tufts of the geniculocortical relay cells, joined together by a rich system of desmosomoid adhesion plaques. The "holes" of the "skeleton" are filled in by the multilobed dendritic appendages of Golgi type II interneurons and the grape-like terminals of the inferior collicular specific afferents. Additional axon terminals of other sources--terminals of descending corticogenicular fibers, axons of the Golgi type II interneurons and terminals of the initial collaterals of the geniculocortical relay cells--contribute only to a very insignificant fraction of neuropil volume. The Golgi type II interneurons are oriented in perpendicular direction to the cell layers so that they may bridge with their dendrites several successive layers. Although the general expression "synaptic glomeruli" used in other relay nuclei for this type of specific synaptic arrangement is hardly applicable to this grid-like neuropil, the essential synaptic articulation pattern of all thalamic relay nuclei is well maintained. The specific inferior collicular afferents are presynaptic to both relay cell dendrites and to the multilobed dendritic appendages of Golgi type II cells, which in turn are presynaptic to the same dendritic regions of the relay cells receiving the bulk of the specific afferents. 相似文献
124.
Lecithin/sphingomyelin ratio (L/S ratio) in amniotic fluid has gained wide clinical acceptance as an index of fetal lung maturity. We determined L/S ratios of amniotic fluids centrifuged at various "g-forces." Our studies demonstrate that the L/S ratio value is highly dependent on the g-force used to prepare the fluid. We recommend standardization of the g-force, time, and temperature used in preparation of the amniotic fluid for L/S ratio determination. 相似文献
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A. Kumar HI. Chan U. Ekanayake A. Wierzbicki N. B. Dahotre 《Journal of Materials Engineering and Performance》1997,6(5):577-582
Thin film nitride coatings were deposited on Si (100) substrates by the pulsed laser deposition (PLD) technique. The PLD method
is a unique process for depositing high quality thin films with novel microstructure and properties. Boron nitride (BN) films
deposited on Si (100) substrates have a higher percentage of c-BN phases when processed in higher nitrogen partial pressure.
Titanium nitride films deposited on Si (100) substrates at a higher temperature (600 °C) have better quality crystallinity
and higher hardness and Young’s modulus values than films deposited at lower temperatures. Nanoindentation technique was used
to measure the mechanical properties of thin films. The film orientation was determined by x-ray diffraction. Atomic force
microscopy (AFM) technique was used to understand the growth structure of the films. 相似文献
127.
含硫铝土矿预焙烧动力学研究 总被引:2,自引:0,他引:2
使用马弗炉、旋转管式炉及流化床对我国含硫一水硬铝石型铝土矿进行预焙烧脱硫性能的研究.考察了焙烧温度、焙烧时间和矿石粒度对焙烧矿中硫含量的影响,并根据实验结果对750~800℃温度范围内不同焙烧方式下矿石脱硫预焙烧动力学进行分析.实验和计算结果表明,不同焙烧方式下焙烧矿中硫含量在750和800℃焙烧温度下均随焙烧时间的延长而下降,马弗炉、旋转管式炉焙烧矿在该焙烧条件下反应表观活化能分别为46.895l和33.090kJ/mol,流态化焙烧反应表观活化能为505.727kJ/mol. 相似文献
128.
DM Katschinski R Benndorf GJ Wiedemann DL Mulkerin R Touhidi HI Robins 《Canadian Metallurgical Quarterly》1999,22(1):67-70
Calculation of the pA2 value and dissociation constants for an antagonist from the effects observed on isolated smooth muscles can be done in two ways: using Schild's plot procedure or Schild's equation. In our study we used the effects of muscarinic antagonists observed in experiments on isolated human and feline stomach and rat gastric fundus. Only the estimates of pA2 values and dissociation constants made using the Schild's equation on the basis of the lowest antagonist concentrations were not significantly different from the values calculated using the Schild's plot procedure. This suggest that, when it is impractical to perform the full Schild's plot procedure, the best estimate of pA2 values and dissociation constants can be done with the lowest antagonist concentration that significantly inhibits the effects of an agonist on an isolated smooth muscle preparation. 相似文献
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130.