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101.
K Jármay G Karácsony Z Ozsvár I Nagy J Lonovics Z Schaff 《Canadian Metallurgical Quarterly》1998,139(15):875-881
BACKGROUND AND AIMS: Interferon-alfa (IFN-alfa) has recently been introduced for chronic C hepatitis treatment; however, the response rate is merely 25-50%. The aims of this follow-up study were to compare the efficacy of 6 and 12-month IFN-alfa treatment via liver biopsy scores and to evaluate the correlation with the biochemical response. PATIENTS AND METHODS: 20 chronic C hepatitis patients were studied. 10 patients received IFN-alfa therapy for 6 months, and 10 for 12 months (3 million units three times a week). Liver biopsy material was taken before and after therapy. RESULTS: There was a significant serum alanine aminotransferase (ALT) level improvement in both groups, but a significant histological improvement in necroinflammatory activity (grade) occurred only in the 12-month group. The Chevallier stage scores demonstrated a significant progression in both groups. CONCLUSIONS: 12-month IFN-alfa treatment affords a better response in the liver histology grade and serum ALT level, but not the stage; a normal ALT does not guarantee hepatitis inactivity. Liver biopsies appear indispensable for monitoring the fibrotic changes in chronic C hepatitis. 相似文献
102.
B Bódis O Karádi P Németh C Dohoczky M Kolega G Mózsik 《Canadian Metallurgical Quarterly》1997,61(16):PL 243-PL 248
The direct gastric mucosal cellular effect of four PL-10 substances (a synthesized part of human body protection compound, BPC containing 14 or 15 amino acids) was studied on freshly isolated rat gastric mucosal cells and on a mouse myeloma cell line (Sp2/0-Ag14) in an ethanol-induced cell injury model. The examined substances were not toxic for the cells. Two of them proved to be significantly protective against the direct cellular damaging effect of ethanol (PL 10.1.15AK-3 in 5 microg/ml dose and PL 10.1.AK14-2 dose-dependently, ED50=50 ng/ml) on gastric mucosal cells. This cytoprotective effect was failured on mouse myeloma cells. Based on these results a part of the in vivo protection induced by BPC seems to be a direct cellular protective effect to gastric mucosal cells. 相似文献
103.
S. Kar 《Solid-state electronics》1975,18(2):169-181
Very accurate and reliable values of the difference between silicon electron affinity, χSi, and the metal work function, ΦM, have been obtained for seven different metals by the MOS flat-band capacitance technique. Different MOS structures with the same interface charge density and the same metal but varying oxide thickness were manufactured on the same wafer by employing a small temperature gradient during steam oxidation in an r.f. induction heated vertical furnace. The flat-band voltage, VFB, vs oxide thickness, tox, graphs obtained are very good straight lines. Use of both p- and n-Si in case of the metals Au and Cr produced two values of the silicon bandgap EG. The value of EG obtained in case of Au differed from the established value of 1·11 eV at room temperature by ?0·04 eV only, and by 0·07 eV in case of Cr. This gives an indication of the experimental accuracy of the ΦHS = ΦM ? χSi values. obtained by this technique is 0·73 eV for Ag. ?0·11 eV for Al, 0·82 eV for Au, ?0·06 eV for Cr, 0·63 eV for Cu, ?1·05 eV for Mg, and ?0·82 eV for Sn. The total inaccuracy is limited to . 相似文献
104.
S. Kar 《Solid-state electronics》1975,18(9):723-732
Characteristics of interface states and interface charges of MOS structures with steam grown oxides and different metal contacts were investigated. Steam oxidation was carried out in an RF furnace under the influence of a d.c. bias. Interface state density Nis as well as the interface charge density at flat band QicFB were found to be independent of the oxide thickness between 150 and 5000 Å, independent of steam oxidation temperature between 900 and 1150°C, but dependent on the contact metal. Metals with smaller work functions were found to have lower Nis and QicFB. Post oxidation annealing in nitrogen at high temperatures reduced both Nis and QicFB. The silicon type had no influence on the interface state density, but p-type silicon had a higher interface charge density at flat band than n-type silicon. Post metallization annealing in nitrogen at low temperatures completely removed a slight slow trapping instability observed before the heat treatment but increased QicFB. MOS structures with oxides grown without bias had much higher interface state density as well as QicFB, however a short postmetallization annealing was very effective in greatly reducing these. The above experimental facts suggest that the interface charges result from acceptor type interface states and fixed positive charges at or near the interface. Protons or SiH groups are very likely to be the source of the fixed positive charges while likely source for the acceptor states are the OH radicals. 相似文献
105.
The growth responses of an acetate-utilizing isolate of Butyrivibrio fibrisolvens to CO2, acetate and pyruvate were determined using a chemically-defined medium. Carbon dioxide was essential for growth and both acetate and pyruvate increased growth. 14C from [I-14C]pyruvate appeared predominantly in formate and lactate. These results, together with those obtained with enzyme preparations, indicated pyruvate synthase, pyruvate-CO2 exchange and pyruvate formate lyase to be active. 相似文献
106.
The Self-Organizing Map (SOM) network, a variation of neural computing networks, is a categorization network developed by Kohonen. The theory of the SOM network is motivated by the observation of the operation of the brain. This paper presents the technique of SOM and shows how it may be applied as a clustering tool to group technology. A computer program for implementing the SOM neural networks is developed and the results are compared with other clustering approaches used in group technology. The study demonstrates the potential of using the Self-Organizing Map as the clustering tool for part family formation in group technology. 相似文献
107.
Forty patients of HBV related cirrhosis of the liver were studied for the presence of delta infection and subsequently the clinical features, course and outcome of these delta infected cases was compared with those of delta uninfected cases. Out of 40 patients studied, only four patients (10%) were reactive for anti-delta antibodies. The incidence of delta infection was common in the younger age group (31.25 +/- 4.78 years) as compared to the older age group (48 +/- 7.25 years) at p < 0.001. Hepatic Encephalopathy was seen in only 13.88% of delta negative patients as compared to 75% of delta infected patients (p < 0.05). During follow up period of 1 year, 75% of patients died in the delta virus infected group as compared to 22.22% in the delta negative group. The mortality was significantly higher in Child's class C (P < 0.01). So delta virus infection is associated with a more severe course of illness and a poorer prognosis in HBV related cirrhotics. 相似文献
108.
Mridul Gautam Krishnendu Kar Heping Yang Kelly Clifton John T. Jurewicz 《Particulate Science and Technology》1993,11(1):57-71
This paper describes the history of LDV measurements employed in research involving gas-solid flows. Much of the discussion deals with measurement techniques employed to obtain separate and simultaneous solid and gas phase velocities. Also, LDV based measurement techniques that are used to obtain particle size and concentration information in conjunction with the velocity measurements are presented. 相似文献
109.
C Varga I Pávó D Lamarque Z Szepes J Kiss G Karácsony FA László F László 《Canadian Metallurgical Quarterly》1998,352(2-3):257-261
Administration of a low dose of endotoxin (from Escherichia coli, 3 mg kg(-1), i.v.), which does not affect vascular permeability or blood pressure over 1 h, leads to the release of endogenous vasopressin and damage to the mucosal microvasculature. Thus, endogenous vasopressin could be involved in septic shock. In the present study, we investigated the role of endogenous vasopressin in gastrointestinal mucosal injury induced by acute endotoxin shock, which was generated in rats by administering a high dose of E. coli endotoxin (50 mg kg(-1), i.v.). Tissues were removed 15 min after endotoxin. The vasopressin V1 receptor antagonist, d[CH2]5Tyr[Me]arginine-vasopressin (0.2-1 microg kg(-1), i.v.), was injected 10 min before endotoxin. Monastral blue (30 mg kg(-1), i.v.), which stains damaged vasculature, was injected 10 min before autopsy. Endotoxin reduced systemic arterial blood pressure (from 115+/-5 to 42+/-4 mmHg), generated macroscopic and microvascular injury, and elevated plasma vasopressin levels (from 3.4+/-0.2 to 178+/-16 pg ml(-1)). The vasopressin V1 receptor antagonist reduced this macroscopic injury, and in the vasopressin-deficient Brattleboro rat a similar reduction of gastrointestinal mucosal damage was found. Substantial decreases in endotoxin-induced microvascular damage were observed in each tissue, e.g., the gastric Monastral blue staining was reduced by 47+/-3% and 96+/-3% (P < 0.01) after vasopressin V1 receptor antagonist treatment and in Brattleboro rats, respectively. Vasopressin, acting through its V1 receptors, thus appears to be involved in acute endotoxin shock-provoked gastrointestinal injury. 相似文献
110.