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1.
Ss "were first given the F Scale and a measure of anti-Negro prejudice… . Four weeks later they read a case history of a person who was prejudiced and authoritarian. Half of the subjects were told that the person in the case history was similar to themselves in background and objective personal characteristics. The other half… that the person was dissimilar to them. Three weeks later the F Scale and the anti-Negro prejudice scale were readministered. It was found that those low in prejudice at the first administration became more prejudiced but only if they were told the case history was about someone like themselves… . These results were interpreted in terms of the social support for suppressed 'wrong' feelings and in terms of the pressures to achieve cognitive consistency in one's self-concept." From Psyc Abstracts 36:04:4GD65S. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
2.
Bending of 15 to 24 degrees is observed within crystal structures of B-DNA duplexes, is strongly sequence-dependent, and exhibits no correlation with the concentration of MPD (2-methyl-2,4-pentanediol) in the crystallizing solution. Two types of bends are observed: facultative bends or flexible hinges at junctions between regions of G.C and A.T base-pairs, and a persistent and almost obligatory bend at the center of the sequence R-G-C-Y. Only A-tracts are characteristically straight and unbent in every crystal structure examined to date. A detailed examination of normal vector plots for individual strands of a double helix provides an explanation, in terms of the stacking properties of guanine and adenine bases. The effect of high MPD concentrations, in both solution and crystal, is to decrease local bending somewhat without removing it altogether. MPD gel retardation experiments provide no basis for choosing among the three models that seek to explain macroscopic curvature of DNA by means of microscopic bending: junction being, bent A-tracts, or bent general -sequence DNA. Crystallographic data on the straightness of A-tracts, the bendability of non-A sequences, and the identity of inclination angles in A-tract and non-A-tracts B-DNA support only the general-sequence bending model. The pre-melting transition observed in A-tract DNA probably represents a relaxation of stiff adenine stacks to a flexible conformation more typical of general-sequence DNA. 相似文献
3.
T Abelin 《Canadian Metallurgical Quarterly》1993,38(5):259-267
Both public health and social and preventive medicine are characterised by the common goal of promoting, maintaining and improving health and preventing disease, and both are concerned with a population-related, preventive and environmental perspective. But whereas public health is interdisciplinary and goes far beyond the medical focus, social and preventive medicine is medically based and forms a bridge between public health and medical practice. Research in a department of social and preventive medicine serves to support preventive and medico-social activities in medical practice as well as in public health. This is illustrated by results from research conducted at the author's department during the last twenty years. Examples are research in support of smoking cessation activities, and research used for the planning of care for the elderly. Both the research and the teaching activities of the department take into account the population focus of public health as well as the focus on individual medicine in clinical practice. 相似文献
4.
The fluorescent cholesterol analogues, cholesta-5,7,9(11)triene-3-beta-ol (I) and ergosta-5,7,9(11)-22-tetraene-3-beta-ol (II), have been shown to be readily incorporated by various tissues and lipoproteins in rabbits maintained on diets supplemented with these fluorophores. Human erythrocytes and lipoproteins were also found to incorporate I and II in vitro under physiological conditions. The thermotropic behavior of the lipoproteins and erythrocyte membranes labeled with sterols I and II was evaluated using temperature-dependent fluorescence polarization and/or fluorescence intensity spectra. Erythrocyte ghosts, fluorescently labeled in vivo (rabbit) or in vitro (rabbit and human), were found to undergo a reversible thermally induced transition at 24 +/- 2 degrees C. A similar transition occurring at higher temperatures was also observed in fluorescently labeled human and rabbit LDL particles. Furthermore, the transition temperatures and relative microviscosities of the in vivo labeled rabbit LDL particles were found to be dependent upon the amount of sterol present in the rabbits' diet. No evidence of a similar thermotropic transition was observed in any of the HDL particles. These results are discussed in terms of a thermotropic reordering of cholesterol clusters existing in the erythrocyte membrane and of the cholesteryl ester core present within the low density lipoprotein particle. 相似文献
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6.
Supernatants obtained after incubation of tumor patient lymphocytes with the homologous tumor-associated antigen (TAA) elicit adherence inhibition in normal guinea pig peritoneal cells. From 37 tested patients with different carcinomas, the supernatants of 30 caused more than 10 per cent adherence inhibition (breast cancer 11/11, lung cancer 7/8, colon cancer 6/7, stomach cancer 6/11). Besides 40 healthy blood donors were tested to a panel of TAA. There was a reactivity more than 10 per cent only in 2 cases. The supernatants of 14 patients with nonmalignant disorders produced adherence inhibition more than 10 per cent in 2 cases. By incubation of tumor patient lymphocytes with the human encephalitogenic protein the supernatants of 19/27 patients elicited a positive reaction. The results suggest that anti-tumor immunity can be detected in an indirect heterologous adherence inhibition system. 相似文献
7.
XW Tang CC Hsu JV Schloss MD Faiman E Wu CY Yang JY Wu 《Canadian Metallurgical Quarterly》1997,17(18):6947-6951
Taurine is known to be involved in many important physiological functions. Here we report that both in vivo and in vitro the taurine-synthesizing enzyme in the brain, namely cysteine sulfinic acid decarboxylase (CSAD), is activated when phosphorylated and inhibited when dephosphorylated. Furthermore, protein kinase C and protein phosphatase 2C have been identified as the enzymes responsible for phosphorylation and dephosphorylation of CSAD, respectively. In addition, the effect of neuronal depolarization on CSAD activity and 32P incorporation into CSAD in neuronal cultures is also included. A model to link neuronal excitation and CSAD activation by a Ca2+-dependent protein kinase is proposed. 相似文献
8.
I Crisostomo A Zayyad DW Carley J Abubaker E Onal EJ Stepanski M Lopata RC Basner 《Canadian Metallurgical Quarterly》1998,85(4):1413-1420
To determine sleep effects on baro- and ventilatory responses to transient chemo- and barostimulation in African-Americans and Caucasians, 26 nonobese normotensive young subjects (13 African-Americans and 13 Caucasians) were studied awake and in non-rapid-eye movement (NREM) and rapid-eye-movement sleep during induced transient hypoxemia (N2), hypertension (phenylephrine, PE), and concomitant hypoxemia and hypertension (N2 + PE). Arterial blood pressure was recorded by plethysmographic volume clamp, minute ventilation by pneumotachograph, and arterial O2 saturation by pulse oximeter. For all subjects, chronotropic baroresponse (Deltapulse interval/Deltasystolic blood pressure, where Delta is change) increased with NREM sleep (P = 0.007). Baroresponse slope was greater in Caucasians than in African-Americans (ANOVA, P = 0.02). Hypoxemic ventilatory response (Deltaminute ventilation/Deltaarterial O2 saturation) was greater in African-Americans than in Caucasians in NREM sleep (P = 0.01), as was hypoxemic attenuation of baroresponse (N2 + PE, P = 0.03). These data suggest sleep-related differences in arterial chemo- and baroreceptor responses in normal young African-Americans and Caucasians, which may have implications concerning development of systemic hypertension. 相似文献
9.
Translated from Poroshkovaya Metallurgiya, No. 5(317), pp. 77–80, May, 1989. 相似文献
10.
BM Sutherland 《Canadian Metallurgical Quarterly》1981,77(1):91-95
In many procaryotic and eucaryotic cells, photoreactivating enzyme mediates light-dependent repair of UV-induced damage: the enzyme binds to a pyrimidine dimer in DNA, and, on absorption of a photon (300-600 nm), specifically monomerizes the dimer, thus repairing the DNA. Photoreactivating enzyme has been found in human tissues and human cells in culture; human cells in culture can photoreactivate cellular dimers, and can mediate photoreactivation of Herpes (human fibroblasts) and Epstein-Barr virus (human leukocytes). Measurements of pyrimidine dimer formation and repair in human skin indicate that detectable numbers of dimers are formed at 1 minimal erythemal dose, that the dimers are rapidly removed in skin kept in the absence of light, and they are more rapidly removed when the skin is exposed to visible light. 相似文献
11.
The response of P. falciparum to chloroquine and pyrimethamine-sulfadoxine in vivo and chloroquine and amodiaquine in vitro was investigated in parasitaemic school children from six locations. Mean parasite sensitivity to chloroquine at day 7 was 74% (range 61-97) with parasite clearance rates between 2-3 days and complete defervescence in 85% of febrile children. Sensitivity declined in the four sites followed up to day 14 to 45% (range 37-53). Parasites were significantly more sensitive to pyrimethamine/sulfadoxine at 5/6 sites (100% day 7) but 5% of subjects became parasitaemic by day 14. In vitro isolates were significantly less sensitive to chloroquine than to amodiaquine with a mean 99% effective concentration of 348 mumol/L compared to 6.44 mumol/L. Clearly the role of chloroquine as the primary therapy for uncomplicated P. falciparum malaria should be reconsidered especially in the light of increasing disease severity and resurgence. Amodiaquine may be suitable alternative with pyrimethamine/sulfadoxine as second line and for more severe malaria prior to referral. The cost of alternative antimalarials and the dynamic and deteriorating pattern of resistance are powerful arguments for more objective slide diagnosis to minimise drug pressure and a regular drug sensitivity surveillance system. We believe that the latter should concentrate on measuring clinical drug efficacy in symptomatic outpatients rather than in asymptomatic children while the former needs more pragmatic and economical strategies possibly centred on seasonality and risk. 相似文献
12.
ME Farago P Kavanagh R Blanks J Kelly G Kazantzis I Thornton PR Simpson JM Cook HT Delves GE Hall 《Canadian Metallurgical Quarterly》1998,123(3):451-454
Increasing Pt concentrations from vehicle catalysts have been reported from a number of countries. Analysis of Pt and Pd in soils and road dusts taken from areas of high and low traffic flows in SE England show concentrations of Pt in the range < 0.30-40.1 ng g-1 and Pd in the range < 2.1-57.9 ng g-1. Higher concentrations of Pt are associated with high traffic densities. Samples taken from streets of lower traffic flows were found to contain the lower concentrations of the ranges. Pilot studies of Pt concentrations in blood and urine using ICP-MS have been carried out. Platinum concentrations in whole blood were: precious metal workers, 780-2170, mean 1263 pmol l-1 (0.152-0.423, mean 0.246 microgram l-1); motorway maintenance workers, 645-810, mean 744 pmol l-1 (0.126-0.158, mean 0.145 microgram l-1); Imperial College staff, 590-713, mean 660 pmol l-1 (0.115-0.139, mean 0.129 microgram l-1). Platinum concentrations in urine in pmol Pt per mmol creatinine were: precious metal workers, 122-682, mean 273 [0.21-1.18, mean 0.47 microgram Pt (g creatinine)-1]; motorway maintenance workers, 13-78, mean 33.7 [0.022-0.135, mean 0.058 microgram Pt (g creatinine)-1]; Imperial College staff, 28-130, mean 65.6 [0.048-0.224, mean 0.113 microgram Pt (g creatinine)-1]. Detection limits were 0.03 microgram l-1 for both blood and urine. The possible health effects of increasing Pt in the environment are discussed. Platinum provides an excellent example of the significance of speciation in metal toxicity. Platinum allergy is confined to a small group of charged compounds that contain reactive ligand systems, the most effective of which are chloride ligand systems. Metallic Pt is considered to be biologically inert and non allergenic and since the emitted Pt is probably in the metallic or oxide form, the sensitising potential is probably very low. Platinum from road dusts, however, can be solubilised, and enter waters, sediments, soils and the food chain. There is at present no evidence for any adverse health effects from Pt in the general environment, particularly allergic reactions. 相似文献
13.
Berlucchi G.; Sprague J. M.; Levy J.; DiBerardino A. C. 《Canadian Metallurgical Quarterly》1972,78(1):123
Monocularly trained 11 adult split-brain cats with unilateral ablation of pretectum and/or superior colliculus in flux and form discriminations. When the midbrain lesions involved both colliculus and pretectum, there was a severe impairment in learning pattern discriminations using the eye on the lesion side. In those cases with the lesions chiefly in the colliculus or in pretectum, the deficit was present but less marked. When these same discriminations were taught before the midbrain lesion, no loss in retention was found postoperatively. (78 ref.) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
14.
In 7 ewes during late pregnancy, peripheral plasma concentrations of oestrogens were correlated with uterine activity (P less than 0-01; r=+0-47). In myometrial tissue, the concentration of progesterone was similar to that in plasma; it rose to a plateau from Days 115 to 130 of pregnancy and then fell, but was still detectable during parturition. Myometrial oestrogen concentration was much higher than in plasma; from a peak at Days 100-115 it decreased, but rose sharply just before parturition. 相似文献
15.
The influence of sex, pregnancy and parturition of biological accumulation and metabolic fate was studied in Sherman rats. 3H-epinephrine was used as a tracer to determine differences in metabolite formation in normal males and females as well as pregnant rats from 18 days post coitum to the end of parturition. The disappearance of 3H-epinephrine and its metabolites was measured in blood, heart, kidney and brain at different intervals but 20 min after the injection of tracer was found the most appropriate time to find appreciable radioactivity in most of the organs studied. All the comparisons for 3H-epinephrine accumulation and its transformation to metabolites have been reported 20 min post-perfusion period. Marked changes of high statistical significance in 3H-epinephrine accumulation and its transformation to 3H-metanephrine and 3H-acid metabolities were observed between males and females. Heart, adrenals, and spleen showed lower rate of metabolism but higher rate of accumulation during pregnancy. Kidney, ovary, and uterus demonstrated higher rate of metabolism but lower rate of accumulation during gestation. In brain regions, hypophysis discriminated greatly between males and females for the three parameters studied. There were important alterations in metabolite formation during 18 and 21 days of pregnancy. The observed variations have been considered due to modified endocrine activity during pregnancy and parturition. 相似文献
16.
Moskowitz D. S.; Schwartzman Alex E.; Ledingham Jane E. 《Canadian Metallurgical Quarterly》1985,94(1):30
Examined stability and change in aggression and withdrawal in the context of both normal and deviant behavioral development. The design included 3 age cohorts with a total of 653 Ss separated in age by 3 yrs. Aggression and withdrawal were measured using the Peer Evaluation Inventory initially when the Ss were in Grades 1, 4, and 7 and a 2nd time when the Ss were in Grades 4, 7, and 10, respectively. Members of 4 classification groups were included in the sample: 183 Ss in an aggressive group, 219 Ss in a withdrawn group, 251 Ss in an aggressive-withdrawn group, and a nondeviant control group consisting of 1,103 Ss. The stability of aggression was found to be moderately high, regardless of sex of S or grade at time of initial assessment. Moderate stability was found for withdrawal for both boys and girls when initial assessments were conducted at Grades 4 and 7. The withdrawn Ss became more withdrawn over the 3-yr period. It is concluded that, for many children, the problems of aggression and withdrawal do not appear to be transitory. (34 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
17.
The binding characteristics of saxitoxin (STX), a known voltage-gated sodium channel blocker, and its analog saxitoxinol (STXOL), were studied in neuroblastoma, peritoneal macrophage, hepatocytes and PC-12 cell lines. 3H-STXOL bound to the cell-surface sites which appear to be the same as those occupied by 3H-STX and which can, therefore, be identified as STX receptors. The relative agreement of respective Kd obtained by saturation, competition, association and dissociation kinetics for STX and STXOL suggest the absence of any artifact in binding measurements. Unlike STX, STXOL was non-toxic to mice by intratracheal instillation. The major advantage of using 3H-STXOL is that the tritium label is not exchangeable. Data from this study suggest that 3H-STXOL can be used to identify STX receptors at 37 degrees C. 相似文献
18.
P Pienim?ki AL Hartikainen P Arvela T Partanen R Herva O Pelkonen K V?h?kangas 《Canadian Metallurgical Quarterly》1995,36(3):241-248
Placental transfer and metabolism of carbamazepine (CBZ) was studied in a dual recirculating placental cotyledon perfusion system and was also evaluated in 16 pairs of maternal venous and cord blood samples. Among the parameters studied as possible indicators of a successful perfusion, volume changes in perfusate divided the perfusions into two groups, whereas no significant differences between perfusions were noted in blood gas analysis or in antipyrine transfer. CBZ added into the maternal circulation crosses the placenta in the beginning quicker than antipyrine which is in agreement with the different lipid solubilities of these compounds. Because the transfer rates of antipyrine and CBZ were about the same, the mechanism of transfer of CBZ is probably similar to that of antipyrine (passive diffusion). No metabolites of CBZ could be detected in the perfusate by high-performance liquid chromatography (HPLC) or gas chromatography/mass spectrometry. With the improved HPLC methodology for CBZ metabolites, six metabolites were detected in clinical samples, including 10-hydroxy-10,11-dihydro-CBZ (10-OH-CBZ), which has been described earlier in only 1 uremic patient. Relative levels of metabolites showed significant individual differences. CBZ crosses perfused placenta rapidly, but this does not contribute to CBZ metabolites detected in maternal and fetal circulation. 相似文献
19.
Israel Orbach; Seymour Feshbach; Gabrielle Carlson; Hananyah Glaubman; Yigal Gross 《Canadian Metallurgical Quarterly》1983,51(5):661
Attraction and repulsion by life and death in 52 suicidal and 58 normal 6–12 yr olds were measured through responses to questions that followed fairy-tale stories. Each story represented 1 of the 4 attitudes. Parallel forms of the test were administered in a time interval of 4 wks. Analyses showed that the 4 attitudes were distinguishable from each other and that the response profile of the suicidal Ss was significantly different from that of normal Ss. Suicidal Ss, in contrast to normal Ss, showed a high degree of repulsion by life and attraction to death and a low degree of attraction to life and repulsion by death. In addition, in suicidal Ss the 4 attitudes were more distinguishable from each other but at the same time were more conflictual. The correlations between the scores of the 1st administrations indicate that 3 of the 4 attitudes have a moderate reliability for both normal and suicidal children. (19 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献