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131.
Angiotensin I-converting enzyme (ACE) inhibitory activities of aqueous extracts of Chinese commercial soypaste were investigated in this work. Six samples from northern China showed potent ACE inhibitory activities with IC50 values less than 40.0 μg/mL. ACE inhibitors in the sample with the strongest activity were purified by ultrafiltration, solid-phase extraction and gradient RP-HPLC. According to spectroscopic methods, a compound (M328.1) was separated as C15H21NO7. It was supposed to be a conjugate of phenylalanine and glucose generated by Maillard reaction during soypaste production, providing support on the contribution of Maillard reaction products to the ACE inhibitory activity of the sample. Results further indicated that the total ACE inhibition by the sample occurred from the combined function of various bioactive substances, suggesting that Chinese soypaste could be a good source of ACE inhibitors for exploring functional foods or ingredients with antihypertensive effect.  相似文献   
132.
 This paper describes the results of in-situ measurements of magnetic susceptibility in landslide deposits along the Tsurukawa fault zone in central Japan. The measured magnetic susceptibility values range from 0.4 to 9.6×10–3 (in SI) and correspond to the proportions of the two component materials, weathered volcanic ash and faulted rock fragments. The study shows that landslide deposits along the Tsurukawa fault zone are composed of varying proportions of weathered volcanic ash. The results contrast with some general assumptions concerning landslides along fault zones in Japan. Received: 16 April 1999 · Accepted: 10 August 1999  相似文献   
133.
The structures of M2O3–TeO2 (M = Al and Ga) glasses have been investigated by means of 125Te, 27Al, and 71Ga NMR spectroscopies. The structural units of respective cations in M2O3–TeO2 glasses were quantitatively analyzed. The fractions of TeO4 trigonal bipyramid, AlO6 and GaO6 octahedra decreased and those of TeO3 trigonal pyramid, AlO4, AlO5, and GaO4 polyhedra increased with increasing M2O3 content. Based on the local structures around Te, Al, and Ga atoms, the structure models of M2O3–TeO2 glasses were proposed.  相似文献   
134.
In the weak magnetic field perpendicular to the discharge electric field, both the electrons and positive ions are transported in the direction of E×B drift by the space charge electric field produced by the preceded electrons. As a result, radicals are generated uniformly outside of discharge space between the electrodes in the direction of E×B drift. On the other hand, negatively charged heavy particles such as dust particles can be removed from discharge space in the direction opposite to E×B drift of plasmas. The authors have studied the transport mechanisms of magnetized dusty plasmas and its applications for the large-area uniform a-Si:H thin film deposition in plasma CVD methods. This paper reviews the transport phenomena and the transport mechanisms of dust particles and the results of film preparation under particle-free process conditions.  相似文献   
135.
A micro-space cell culture system was recently developed in which cells such as hepatocytes can be cultured and formed into a multicellular three-dimensional (3D) architecture. In this study, we assessed the performance of HepG2 cells cultured in this micro-space cell culture system in a drug toxicity test, and evaluated the effects of micro-space culture on their hepatocyte-specific functions. The micro-space cell culture facilitated the formation of 3D HepG2 cell architecture. HepG2 cells cultured in a micro-space culture plate exhibited increased albumin secretion and enhanced mRNA expression levels of cytochrome P450 (CYP) enzyme compared to those cultured in a monolayer culture. When the cells were exposed to acetaminophen, a hepatotoxic drug, the damage to the HepG2 cells grown in micro-space culture was greater than the damage to the HepG2 cells grown in monolayer culture. In addition, human primary hepatocytes grown in micro-space culture also exhibited increased albumin secretion, enhanced CYP mRNA expression levels and increased sensitivity to acetaminophen compared to those grown in monolayer culture. These results suggest that this micro-space culture method enhances the hepatocyte-specific functions of hepatocytes, including drug-metabolizing enzyme activities, making hepatocytes grown in the micro-space culture system a useful tool for evaluating drug toxicity in vitro.  相似文献   
136.
We previously reported that lysophosphatidylinositol (LPI) functions as an endogenous agonist of GPR55, a novel cannabinoid receptor. However, the physiological roles of LPI-GPR55 have not yet been elucidated in detail. In the present study, we found that LPI induced morphological changes in GPR55-expressing HEK293 cells. LPI induced the cell rounding of GPR55-expressing HEK293 cells but not of empty-vector-transfected cells. LPI also induced the activation of small GTP-binding protein RhoA and increased stress fiber formation in GPR55-expressing HEK293 cells. The inhibition of RhoA and Rho kinase ROCK by the C3 exoenzyme and the ROCK inhibitor reduced LPI-induced cell rounding and stress fiber formation. These results clearly indicated that the LPI-induced morphological changes and the assembly of the cytoskeletons were mediated through the GPR55-RhoA-ROCK pathway.  相似文献   
137.
138.
A 58-year-old man with subacute fulminant onset of autoimmune hepatitis (AIH) was treated by leukocytapheresis (LCAP) and bilirubin adsorption therapy (BAT), rather than by administration of high-dose corticosteroids as he had mild glucose intolerance, and a definitive diagnosis of AIH was not obtained on admission; further, there was a risk of viral infection. After initiation of the therapies, serum transaminases and bilirubin, immunoglobulins, anti-nuclear antibodies, and rheumatoid factor decreased rapidly, as did the initially high levels of activated cells and several pro-inflammatory cytokines. Liver inflammation observed on liver biopsy settled during the course of the therapies, with no adverse side effects. A pause in the therapies was associated with deterioration; however, restoration of apheresis was followed by normalization. Remission was sustained throughout the period monitored, except for a recurrence 14 months after discharge, which was successfully resolved by two additional LCAP sessions. These results suggest that LCAP influences the causal mechanism(s) of exacerbation of AIH.  相似文献   
139.
A retrospective study of 85 patients with IgA nephropathy was undertaken to determine the long-term effect of tonsillectomy. Forty-three patients (24 males and 19 females) had received tonsillectomies (Group A) and 42 patients (17 males and 25 females) had not (Group B). These patients had been followed up for more than 5 years after renal biopsy. The average age at the initial renal biopsy was 25.72 years in Group A, and 33.16 years old in Group B. The average period of renal biopsy to tonsillectomy in Group A was 10.47 months. The average follow-up period was 8 years and 9 months in both groups. At the beginning of treatment, the two groups were well matched in terms of creatinine clearance, urinalysis, and blood pressure. Six patients in Group A and eight patients in Group B were treated with steroids. The glomerular injury detected at the renal biopsy was more extensive in Group A than in Group B. Renal function in the two groups was compared. The clinical remission rate in Group A was significantly higher than in group B (P<0.05). The stable renal function rate in Group A was significantly higher than in Group B (P<0.05). The renal survival rate was 97.7% in Group A and 83.3% in Group B, but there was no significant difference between the two groups. Histologically, the rate of remission of the minor lesion in Group A was significantly higher than in Group B (P < 0.05). Our results showed that tonsillectomy for IgA nephropathy was clinically of great value.  相似文献   
140.
The mechanical properties of polyphenylene sulphide (PPS) and liquid crystalline polymer (LCP) blends were investigated over a range of temperatures. The effect of blend composition on the brittle-ductile transition temperature (B-D) was also studied by differential scanning calorimetry and scanning electron microscopy. Blends of various compositions (PPS/LCP; 90/10, 75/25, 50/50 and 25/75) were prepared and injection moulded. The bending test temperature was varied between –40 and 150 °C. The results showed a rapid load drop at the B-D transition region. The B-D transition temperature occurred in unannealed pure PPS, 90/10, 25/75 and 50/50 blends around 75 °C whilst in the annealed sample it was observed around 100 °C. In pure LCP and 25/75, no transition occurred. Partial miscibility of PPS and LCP was confirmed by SEM observations, bending modulus and thermal properties. The use of LCP, as a good reinforcing agent which can improve processability and modulus, is discussed.  相似文献   
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