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排序方式: 共有536条查询结果,搜索用时 15 毫秒
61.
62.
Abstract – The color stability of three composite resins used in the inlay/onlay technique was determined by means of irradiation with UV-light and by water storage. Generally, water storage resulted in greater changes in color than did UV-light, but no correlation was found between the results of the two chromogenic procedures. The microfilled composite resin was the least color stable material, but none of the resins had alarmingly low color stability. 相似文献
63.
ULRICH ROGER G.; PETRELLA DIANE K.; LARSEN ERIK R.; COX JEFFREY W.; CRAMER CLAY T.; PIPER RICHARD C.; GRAY JACK E. 《Toxicological sciences》1990,14(1):60-70
Hepatic Changes Produced by 30-Day Administration of a NovelAminocyclitol Antibiotic, Trospectomycin Sulfate, to LaboratoryAnimals. ULRICH, R. G., PETRELLA, D. K., LARSEN, E. R., COX,J. W., CRAMER, C. T., PIPER, R. C, AND GRAY, J. E. (1990). Fundam.Appl. Toxi-col. 14, 6070. The studies described herewere done to characterize the hepatic response to a new aminocyclitolantibiotic, trospectomycin sulfate, administered intravenously(beagle dog) or subcutaneously (Sprague-Dawley rat) at a varietyof dose levels, to investigate reversibility of observed changes,and to document any untoward effects of subchronic trospectomycinsulfate administration. Both species showed significant elevationsin serum levels of alanine and aspartate transaminases in higherdose groups. In the dog only, a transient neuromuscular blockadewas also observed within higher dose groups. No other functional,morphological, or serum chemical changes were observed. Examinationof liver by electron microscopy revealed the presence of cytoplasmiclamellar inclusion bodies, concentrated in the bile canalicularregion of the hepatocytes. Occurrence of the lamellar bodiesand coincident transaminase increases were found to be reversibleupon discontinuance of treatment (studied in the dog). Electronmicroscopy of acid phosphatase cytochemistry in the rat indicatedthat most, but not all, of the lamellar bodies contained thisenzyme. This observation suggests that they may be derived fromthe lysosome, or once formed become lysosomal. 相似文献
64.
We discuss deinstitutionalization and the question of how long-termmentally ill persons adjust to life outside institutions.An interview survey was conducted in 1990 with 61 persons whohad been discharged to the community from a mental hospitalin the County of Värmland, Sweden during the 1980s afterat least five years inpatient care. The question of accommodationwas solved for all the interviewees prior to discharge and allnow live in modern apartments. Each discharge was preceded byan individual plan. The majority of the 61 ex-patients stillhad contact with psychiatry in some form but only 19 had beentreated in inpatient psychiatric care since they were discharged.While the ex-patients' material standard of living was satisfactory,the situation with respect to the occupation and fellowshipwas not. The need for intermediate forms of individually adaptedoccupation and supportive housing conditions is discussed. 相似文献
65.
PER CARLENS ALF HOLMGREN RUNE JONASSON CHRISTIAN LANDOU ERIK ORINIUS 《Journal of internal medicine》1983,214(1):43-47
ABSTRACT. The mechanism of ischaemic ST depression and the cause of its low sensitivity to coronary artery stenosis are not well understood. Of 30 patients with severe stable effort angina, 19 (63%) showed ischaemic ST depressions after exercise (the STAE group) and 11 did not. The highest load during the symptom-limited exercise test and the heart rate on that load did not differ between the two groups. The clinical characteristics and angiographic findings were also similar, bat the findings at heart catheterization differed during exercise (in supine). Although the load was similar, the stroke index was significantly lower (38 vs. 53 ml/m2 BSA) and the left ventricular end-diastolic pressure rose to a significantly higher value in the STAE group (40 vs. 32 mmHg). When STAE occurred, they were exclusively or concomitantly present in chest lead 5. These findings suggest that ischaemic STAE may not reflect regional ischaemia but the consequent left ventricular dysfunction. The mechanism may, for example, be that a sufficiently elevated left ventricular diastolic pressure causes a global subendocardial ischaemia. 相似文献
66.
ERIK KEITH HANSEN 《European journal of oral sciences》1984,92(2):148-155
Abstract – The marginal porosity of four light activated restoratives (Command, Durafill, Prismafill and Silux) was investigated in extracted human teeth It was found that the use of a lowviscous resin prior to application of the restorative materials significantly reduced the marginal porosity in both acid etched enamel cavities and EDTA-cleaned dentin cavities. 相似文献
67.
ERIK KEITH HANSEN 《European journal of oral sciences》1982,90(6):480-483
Abstract – The correlation between the wall-to-wall polymerization contraction close to the surface and the marginal gap in the deeper parts of chemically cured resin fillings was investigated. The investigation was carried out with fillings placed in non-etched dentin cavities in extracted human teeth. A negative correlation was found; i.e. the narrower the marginal gap in the upper part of the cavities, the more pronounced the contraction in the deeper parts of the fillings, and vice versa. 相似文献
68.
KNUD DREYER JÖRGENSEN KAZUO ITOH ERIK CHRISTIAN MUNKSGAARD ERIK ASMUSSEN 《European journal of oral sciences》1985,93(3):276-279
Abstract – Extracted human teeth are frequently used in studies on bonding of composites to dentin. However, little is known about the effect of storing conditions on the results recorded. The purpose of the present work was to measure the wall-to-wall polymerization contraction of a light-cured composite material with and without the use of five different dentin bonding agents in cylindrical dentin cavities prepared in extracted human teeth, either fresh or after storing for up to 4 wk in four different media. No effect of the storing conditions on the width of contraction gaps could be demonstrated when the teeth were stored either in tap water or in a 1.0% aqueous chloramine solution. Aqueous solutions of either 0.1% benzalkonium chloride or 0.9% sodium chloride did occasionally affect the size of the contraction gap. 相似文献
69.
A 68-year-old woman suffering from frequent attacks of supraventricular tachycardia received an implantable, automatic scanning pacemaker for tachycardia termination (PASAR). Electrophysiological study had shown the mechanism to be atrioventricular reentry with retrograde conduction through a concealed bypass tract. During 1 year of follow-up, a total of twenty-one 24-hour Holter recordings documented 554 episodes of tachycardia. In spite of marked fluctuation in tachycardia rate from 135 to 195 bpm and a considerable variation in diurnal pattern of onset of episodes, a clinical improvement resulted. Previous episodes of tachycardia had been isolated and of longer duration. Following implantation, an unexpected observation was made of numerous episodes of supraventricular tachycardia confined to periods lasting up to several hours. This pattern seemed to result from the efficacy of tachycardia termination combined with a continued presence of factors responsible for initiation of tachycardia. 相似文献
70.
ERIK STRANDBERG JOHAN KORDEL RONNY LUNDIN THOMAS WEHLER G
RAN WIDMALM 《Chemical biology & drug design》1997,49(3):254-260
The synthetic C-terminal hGH fragment I179-C182-[SS]-C189-P191 and the related trisulfide peptide I179-C182-[SSS]-C189-P191 have been studied using homonuclear 1H-NMR methods and distance geometry calculations. The 1H-NMR spectra of both the disulfide (diS) and the trisulfide (triS) were completely assigned. Amide proton exchange rates, NOEs and the temperature dependence of the NH chemical shifts indicate a hydrogen bond in triS between Val 185 and Ser 188 stabilizing a turn in this region. 3JH, H coupling constants and NOEs were measured and used as input for distance geometry calculations. For triS two families of structures with averaged pairwise backbone root mean square deviations for Cys 182-Cys 189 of 1.3–1.5 Å were found, only one of which is compatible with experimental data. For diS only one family of structures was found, but with such a low structural definition (backbone rmsd >2Å) that no interpretation into a consensus structure is useful. The generated structures were compared to the crystal structure of the terminal loop in hGH. complexed to its binding proteins. The resemblance was low between the solution structures of the tridecapeptides and the terminal hGH loop. © Munksgaard 1997. 相似文献