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41.
Soymilk coagulation process is the most important step in tofu making. An experimental setup was developed to control the coagulation temperature and heating rate by ohmic heating and to perform impedance measurement in time-sharing mode. Soymilk coagulation process was characterized by electrical impedance spectroscopy. Frequency 10 kHz was chosen to analyze the coagulation process. Normalized conductivity was useful in determination of the endpoint of soymilk coagulation process. The coagulation process was considered as two successive first-order reactions. The rate constant in the first stage was 10 times higher than that in the second stage, both rate constants increased with coagulation temperature. The activation energy in the second stage was three times greater than that in the first stage. The successive reaction process was elucidated by using soymilk coagulation mechanism. The use of impedance measurement to analyze the coagulation process provides a basis for the control of soymilk coagulation process.  相似文献   
42.
McCune-Albright syndrome (MAS) is clinically characterized by polyostotic fibrous dysplasia, cafe au lait pigmentation of the skin and multiple endocrinopathies. Recently activating mutations of codon 201 in the gene encoding Gs alpha have been found in affected tissues in MAS. Herein we report a case of acromegaly associated with multiple bone cysts and skin pigmentation in a 47-year-old women. She had suffered a history of aortitis syndrome. The DNA sequence indicated that a Cys201 for Arg201 substitution was found in the GH secreting pituitary adenoma tissue but not in peripheral mononuclear cells. We speculate that the patient has a possible variant from of MAS characterized by multiple bone lesions skin pigmentation and GH-secreting pituitary adenoma.  相似文献   
43.
In recent logic ULSI's, the problem of device integration density has tended to be dominated by interconnection-related issues rather than transistor-related ones. In seeking to establish an analytical model, this paper describes the limit on integration density caused by electromigration (EM) tolerance. In our model, all signal lines within a logic block are assumed to be local interconnections and to be the predominant factor in integration density. Also in our model, integration density is approximated to be inversely proportional to the average width of signal lines, which can be derived from their width distribution. The width distribution of EM-limited interconnections is connected to the gate width distribution of their corresponding driving transistors. The relation between the two distributions is derived by incorporating an expanded EM model that treats currents in signal lines as bi-directional periodic pulses. Scaling theory is also incorporated to investigate the future trend in integration density in terms of the MOSFET gate length. Calculated results predict that EM tolerance could become a significant restraining factor on the trend toward increasing integration density when MOSFET gate lengths are scaled down to the quarter-micron range. This constraint is found to disappear at moderately lower operation temperatures  相似文献   
44.
We analyzed an amino-terminal modification of beta-amyloid (A beta) peptide in brain, using anti-A beta antibodies that distinguish distinct molecular species. Examination of cortical sections from 28 aged individuals with a wide range in senile plaque density revealed that a molecular species distinct from the standard A beta is deposited in the brain in a dominant and differential manner. This modified A beta peptide (A beta N3(pE)) starts at the 3rd aminoterminal residue of the standard A beta, glutamate, converted to pyroglutamate through intramolecular dehydration. Because plaques composed of A beta N3(pE) are present in equivalent or greater densities than those composed of standard A beta bearing the first amino-terminal residue (A beta N1) and because deposition of the former species appears to precede deposition of the latter, as confirmed with specimens from Down's syndrome patients, the processes involved in A beta N3(pE) production and retention may play an early and critical role in senile plaque formation.  相似文献   
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Intraneuronal accumulation of paired helical filaments (PHF) is considered to be closely related to the neuronal loss observed in brains of patients affected with Alzheimer's disease. The central issue is whether PHF formation itself causes or accelerates the neuronal perikaryal and neuritic degeneration or whether they are simply the consequence of preceding degeneration. We sought to address the issue in part by characterizing the PHF-associated molecules and thus raised a number of monoclonal antibodies to neurofibrillary tangles. One monoclonal antibody, 3F4, strongly reacted with neurofibrillary tangles and some plaque neurites but few neuropil threads. This monoclonal antibody labeled a 65-kDa protein, but not tau or ubiquitin, on a Western blot of human brain extract and immunoprecipitated the same protein. The peptides released from the purified 65-kDa protein had the same sequences as those of a newly identified protein, human collapsin response mediator protein-2. Incorporation into neurofibrillary tangles may deplete soluble, cytosolic human collapsin response mediator protein-2 and lead to abnormal neuritic and/or axonal outgrowth of the tangle-bearing neuron, thus accelerating the neuritic degeneration in Alzheimer's disease.  相似文献   
47.
Autonomous Decentralized Computer Control Systems   总被引:4,自引:0,他引:4  
Ihara  H. Mori  K. 《Computer》1984,17(8):57-66
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48.
A method to identify dyad symmetrical sequence on duplex DNA in a homogeneous system has been investigated. In this method, luminescence from the complex of Tb(III)-phenanthroline-DNA triple helix was utilized.  相似文献   
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