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21.
22.
In order to investigate the fate of orally administered proteins, the absorption of ovalbumin (OVA) from the gastrointestinal tract into both the blood and lymph circulation was quantitatively evaluated. After oral administration, a significant amount of intact OVA was detected in both the plasma and the lymph fluid by means of a two-site enzyme immunoassay. The extent of absorption into the plasma, calculated from the area under the plasma concentration versus time curve of OVA after oral and intravenous administration, was only 0.007-0.008% of the dose. This value is extremely low compared to that after nasal administration, showing the stronger barrier function of the gastrointestinal tract against the invasion of macromolecular proteins into the body. The extent of absorption into the lymph was dose-dependent (0.0007-0.002% of dose), and a higher dose leads to a higher fraction of OVA absorbed into the lymph. Moreover, it was demonstrated that not only the small intestine but also the stomach can absorb OVA. OVA absorbed from the stomach was transferred almost exclusively to the blood circulation, which suggests different mechanisms and/or routes of absorption between the stomach and the small intestine. In order to improve the low oral absorption, OVA was incorporated in liposomes and administered orally. Although the effect of liposomes was not significant, it increased OVA absorption into both the plasma and lymph by about 2 to 3-fold. It was considered that the liposomes suppressed the enzymatic degradation of OVA and released it slowly in the gastrointestinal tract.  相似文献   
23.
There are many expert systems that use experimental knowledge for diagnostic analysis and design. However, there are two problems for systems using only experiential knowledge:
  1. unexpected problems cannot be solved and
  2. acquiring experiential knowledge from human experts is difficult.
To solve these problems, general principles or basic knowledge must be added to expert systems in addition to the experimental knowledge. In response, we previously proposed Qupras (Qualitative physical reasoning system) as a framework for basic knowledge. This system has two knowledge representations, one related to physical laws and the other to objects. By using this knowledge, Qupras reasons about the relations among physical objects, and predicts the next state of a physical phenomenon. Recently, we have improved some of Qupras’ features, and this pater desctibes the following main enhancements:
  1. inheritance for representation of objects,
  2. new primitive representations to describe discontinuous change, and
  3. control features for effective reasoning.
  相似文献   
24.
Anand模型预测63Sn37Pb焊锡钎料的应力应变行为   总被引:4,自引:1,他引:4  
张莉  陈旭  Nose H  Sakane M 《机械强度》2004,26(4):447-450
通过在温度313K~398K、应变率10^-3%/s~10%/s内的一系列恒应变率拉伸实验,研究63Sn37Pb焊锡钎料的力学行为,发现该材料的应力应变关系与温度和应变率有很大的相关性。采用统一型Anand粘塑性本构方程对该材料在较大温度和应变率范围内的应力应变行为进行数值模拟。结果表明Anand粘塑性方程可以有效地描述63Sn37Pb焊锡钎料在10%应变下的温度和应变率相关粘塑性本构行为。  相似文献   
25.
Friction under boundary lubrication was measured using a pendulum-type friction machine. Long straight-chain fatty acids with even carbon numbers, amine, and alcohol were used as additives, and n-hexadecane was used as the base oil.

Effect of the temperature, chain length of additives and additive concentration were investigated.

The phenomena obtained under 373 K were as follows:

1) “Transition concentration” wherein a drastic change of friction coefficient appeared were observed.

2) “Transition concentration” of amine or alcohol solutions appeared at higher concentration than that of acid solution.

3) In “high concentration region,” the friction coefficient gradually increased with the decrease of the concentration.

4) Temperature raise caused a high friction coefficient.

5) Friction coefficient gradually decreased with an increase in chain length.

6) “Transition concentration” shifted toward low concentration with an increase in chain length.

7) No chain-matching effect was observed.

These results are explained introducing a new concept of adsorption mechanism, where both mechanical disturbance, i.e. friction, and adsorption-desorption process of molecules are taken into consideration.  相似文献   
26.
The ultra-HVEM with an accelerating voltage of 3 MV at Osaka University is capable of achieving excellent penetration and resolution for thick specimens. We obtained images of 5-microm-thick slices tilted at angles of up to 70 degrees for biological samples and observed stick-shaped samples of Si devices free from missing zone. These features make the ultra-HVEM an invaluable extension of 3D observation by electron tomography. In this paper, we introduce aspects of ultra-HVEM tomography; specifically, the magnification, the amount of image blurring for thick samples and the electron staining method. Finally, we give some typical applications in the fields of cell biology, pathology and electrical engineering.  相似文献   
27.
28.
This paper presents HELIC-II, a legal reasoning system on the parallel inference machine. HELIC-II draws legal conclusions for a given case by referring to a statutory law (legal rules) and judicial precedents (old cases). This system consists of two inference engines. The rule-based engine draws legal consequences logically by using legal rules. The case-based engine generates legal concepts by referencing similar old cases. These engines complementally draw all possible conclusions, and output them in the form of inference trees. Users can use these trees as material to construct arguments in a legal suit. HELIC-II is implemented on the parallel inference machine, and it can draw conclusions quickly by parallel inference. As an example, a legal inference system for the Penal Code is introduced, and the effectiveness of the legal reasoning and parallel inference model is shown.  相似文献   
29.
Summary A bifunctional living poly(dimethylsiloxane), poly(DMS), was synthesized through the anionic ring-opening polymerization of hexamethylcyclotrisiloxane(D3) (3) with an initiator system consisting of dilithium salt(2) of bis (p-hydroxydimethylsilyl)phenyl ether(1) and N-methylpyrrolidine in THF solution. The subsequent end-capping reaction of the bifunctional living poly(DMS) with dimethylvinylchlorosilane(4) provided the uniform size poly(DMS) having vinylsilane group at the both chain ends(5).  相似文献   
30.
Ozone decomposition of hazardous chemical substance in organic solvents   总被引:3,自引:0,他引:3  
Nakano Y  Okawa K  Nishijima W  Okada M 《Water research》2003,37(11):2595-2598
Performance on the ozonation of hazardous chemicals in non-aqueous solutions, i.e. organic solvents, was studied in comparison with those in water. The specific conclusions obtained from this study are as follows: the rate of decomposition and the specific amount of decomposition per ozone consumption for orange II were higher in organic solvents like acetic acid, acetone, ter-butyl alcohol than in distilled water. The rates of trichloroethylene decomposition in organic solvents like acetic acid, acetone, and ethyl acetate were also higher than those in distilled water.  相似文献   
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