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41.
HW Klafki AI Pick I Pardowitz T Cole LA Awni HU Barnikol F Mayer HD Kratzin N Hilschmann 《Canadian Metallurgical Quarterly》1993,374(12):1117-1122
Motivated by the finding that the amino acid sequence of the Bence Jones protein BJP-DIA was identical to that of the main protein component of the amyloid fibrils obtained from the same patient with AL-amyloidosis, (Klafki, H.-W., Kratzin, H.-D., Pick, A.-I., Eckart, K., Karas, M. & Hilschmann, N. (1992) Biochemistry 31, 3265-3272.), we attempted to create "amyloid-like" fibrils from the Bence Jones protein in vitro, without addition of proteolytic enzymes. Reduction of BJP-DIA, solubilized in PBS, pH 7.4, overnight at 37 degrees C resulted in the formation of a precipitate which had affinity for the dye Congo red. Electron microscopy of negatively stained samples of the reduced protein revealed aggregates of linear unbranched fibrils. SDS-polyacrylamide gel electrophoresis demonstrated that the precipitate consisted almost exclusively of intact light chain molecules. This result makes it possible to deduce a molecular model of these amyloid fibrils generated in vitro. 相似文献
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LG Kupchinski? IuA Barshte?n BG Pogodaev AI Treshinski? 《Canadian Metallurgical Quarterly》1976,(3):80-84
A study was made of a possibility of using Soviet made membranes "Vladipor" with a pore diameter of 16--17 nm for the purpose of concentration and purification of antigenic extracts from stab cultures of S. typhi obtained by the action of typsin, hydrogen peroxide and detergents. Preparations, complete by antigenic structure, were obtained by ultrafiltration, with a good yield. The maximal rate of ultrafiltration was noted in case of "peroxide" antigenic preparations. The use of diafiltration provided a significant reduction of the ash content in the end products. 相似文献
44.
Circulating plasma progesterone (P) has been quantitatively controlled in the rat "model" through highly specific binding by treatment with anti-P (A-P). Knowing the constant, which characterizes the binding of P to A-P in plasma, sequential assays of circulating A-P and A-P bound total P (Pt) revealed the levels of the biologically active unbound P (Pu). The studies showed that at different stages of gestation the mechanisms through which A-P reduces Pu and terminates pregnancy are the same. However, the doses of AP which effectively reduce Pu and also the critical levels of Pu at which pregnancy terminates are different. The moderate and transient physiologic P-withdrawal (Pw) at midterm permits the continuation of normal gestation, but pregnancy is terminated by a drastic and sustained reduction in Pu. In contrast, when Pu is only slightly and briefly reduced below physiologic levels, pregnancy continues and only retarded conceptus growth signals that Pw occurred. Apparently Pw has to be controlled and measured with "razor's-edge" precision to fully expose and define the regulatory significance of this steroid in the maintenance and termination of pregnancy. Short of this precision, the key regulator of the pregnant uterus will remain buried, as it has been during 40 years, in controversial findings. 相似文献
45.
Histories of deliveries and development records of 44 newborns with penumopathies who had died on the first days of life in the presence of phenomena of the syndrome of respiratory disorder were analysed and the newborns' lungs were morphologically investigated. The investigation made it possible to single out the following forms of pneumopathy in newborns: edematous-hemorrhagic, hyaline, atelectatic, aspirated, and mixed. In the majority of cases the syndrome of respiratory disorder was a sequela of hypoxia of the intrauterine origin which continued during the first hours and days of life after birth. Such "primary asphyxia" may lead to the development of pneumopathy in a neonate. On the other hand, "secondary asphyxia" in many cases represent sequelae of penumopathy destructural and functional immaturity of the pulmonary tissue, hypoxia, a higher permeability of vessels of the microcirculatory bed, spasm of small pulmonary arteris contributed considerably to the development of penumopathies. 相似文献
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高炉紫铜风口是由铸造本体和轧制端头两个部分采用TIG手工焊接而成。随着高炉的扩容,为了延长风口使用寿命,提高焊缝物理和力学性能,成功采用了MIG自动焊,满足了高炉生产需求。 相似文献
49.
650轧辊的堆焊修复 总被引:1,自引:0,他引:1
对轧辊断裂部位进行了分析,找出了裂纹形成的主要原因。通过采取焊前预热、低氢焊接和焊后热处理等措施,成功地实现了650轧辊端头断裂的堆焊修复,即以焊代换。同时,延长了轧辊服役周期。 相似文献
50.
针对传统电路硬件复杂及可靠性差等问题,介绍了利用AT89C51单片机和相应的SPI串行接口芯片,构成的一种光纤气敏传感器的数据采集和数据处理部分,在分析了各串行芯片的特点后,详细介绍了该单片机系统的硬件接口电路和软件程序,由于该光纤气敏传感器具有电路简单,体积小,运行可靠等特点,因而具有很好的应用前景。 相似文献