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1.
The in vitro response of wild Gambian Plasmodium falciparum to pyrimethamine is described. Parasites were grown in 100 microliter cultures through schizogony. The number of rings present after 48 hours in drug-treated cultures was expressed as a percentage of the controls. Neither a medium and drug change after 24 hours nor different starting parasitaemias were found to affect the outcome of the assay, although a medium and drug change did increase the multiplication rate. 60 randomly taken pure P. falciparum infections were studied. 57 were sensitive. The ID50 and ID90 of drug-sensitive infections were 1.7 X 10(-9) M and 4.5 X 10(-9) M pyrimethamine respectively. Three infections were resistant (5%) with individual ID50 values of greater than 10(-6) M, 3 and 4 X 10(-9) M and ID90 values of greater than 10(-6) M, 8 and 9 X 10(-7) M. 相似文献
2.
Recoverin is a calcium-binding protein expressed in retinal photoreceptors. It appears to delay the termination of the phototransduction cascade by blocking the phosphorylation of photoexcited rhodopsin. The goal of this study was to determine if recoverin mRNA and protein are expressed in cultured human Y79 retinoblastoma cells, so that this cell line could be used as a model to study the mechanism of recoverin gene expression in the retina. A cDNA encoding human recoverin was PCR cloned and used for prokaryotic expression of recoverin protein. Polyclonal antibodies raised against pure recombinant recoverin were used for western blotting and immunocytochemistry of Y79 cells grown as attachment cultures in the presence of the differentiating agents dibutyryl cyclic AMP (dbcAMP) or butyrate. Northern blot analysis was performed on mRNA extracted from Y79 cells that were also treated with the differentiating agents. In Y79 cell monolayer cultures, recoverin was immunolocalized to the cell cytoplasm, and immunoreactivity was increased dramatically by the addition of 2 mM butyrate to the culture medium. Butyrate treatment also caused an increase in the development of neurite-like cellular processes. Addition of 4 mM dbcAMP resulted in a moderate increase in both recoverin immunoreactivity and number of cellular processes. Western and northern blots of butyrate and dbcAMP-treated Y79 cell cultures demonstrated an increase in recoverin protein and RNA expression, respectively, comparable with that observed with immunocytochemistry. These data suggest that, under the influence of the differentiating agent butyrate, Y79 cells exhibit an increase in expression of the photoreceptor protein recoverin and a concomitant morphological differentiation toward a neuronal phenotype. 相似文献
3.
Surface growth of synchronized bacteria was obtained by means of a suspension of Mycobacterium phlei cells in pentane, the dispersion of which resulted from passage through glass (Ballotini) column. By using standardized conditions, a series of identical cultures were obtained, suitable for studying their evolution as a function of time. By counting colonies every twenty minutes, during ten hours, two doublings were observed, with a generation time of five hours. At the end of a plateau, just before the next doubling, the curve exhibited a marked decrease. Bacteriophages were found in culture medium at the time corresponding to this decrease. In thin sections of the pellicles collected at this time, condensations resembling DNA from phage heads could be noticed within the bacterial cells, as well as free phages in th close neighbourhood of burst cells. The relations between phage and bacteria, and the possible relation between the presence of the phage and the synthesis of phleates has not been determined. 相似文献
4.
FJ Seil 《Canadian Metallurgical Quarterly》1994,35(5-6):445-450
Locus coeruleus axons project to cerebellar cortex in coeruleocerebellar cultures, where they make functional contacts, and also appear as fine fibers in the outgrowth zones. The predominant catecholamine of locus coeruleus neurons in culture is dopamine. When coeruleocerebellar cultures are exposed to cytosine arabinoside to destroy cerebellar granule cells and functionally compromise glia, there is a resultant increase of Purkinje cell survival and a sprouting of Purkinje cell recurrent axon collaterals, plus an increase of catecholaminergic axons accompanied by a doubling of tissue dopamine content. If such reorganized cultures are transplanted with granule cells and glia, a second round of plastic changes ensues in which the Purkinje cell population and the recurrent axon collaterals are reduced to control levels, but catecholaminergic axons and dopamine content remain increased. The maintenance of catecholaminergic axons does not appear to depend on the persistence of target neurons. 相似文献
5.
Grouzet Frederick M. E.; Kasser Tim; Ahuvia Aaron; Dols José Miguel Fernández; Kim Youngmee; Lau Sing; Ryan Richard M.; Saunders Shaun; Schmuck Peter; Sheldon Kennon M. 《Canadian Metallurgical Quarterly》2005,89(5):800
The authors investigated the structure of goal contents in a group of 1,854 undergraduates from 15 cultures around the world. Results suggested that the 11 types of goals the authors assessed were consistently organized in a circumplex fashion across the 15 cultures. The circumplex was well described by positing 2 primary dimensions underlying the goals: intrinsic (e.g., self-acceptance, affiliation) versus extrinsic (e.g., financial success, image) and self-transcendent (e.g., spirituality) versus physical (e.g., hedonism). The circumplex model of goal contents was also quite similar in both wealthier and poorer nations, although there were some slight cross-cultural variations. The relevance of these results for several theories of motivation and personality are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
6.
7.
M Turgut 《Canadian Metallurgical Quarterly》1998,14(4-5):161-166
The term "cerebellar mutism" refers to a specific disorder in which a complete but transient loss of speech, followed by dysarthria, occurs following resection of intrinsic posterior cranial fossa tumors or cerebellar hemorrhages, or upon trauma. Although it is well known that the lack of long-tract findings and cranial nerve (CN) involvement is the rule, the pathophysiology of cerebellar mutism has not been clearly elucidated. A review of the relevant literature disclosed 93 patients with this condition, the majority of these being in the pediatric age group. The neuropathological findings were as follows: 57 primitive neuroectodermal tumors (PNET), 19 astrocytomas, 10 ependymomas, 5 vascular malformations, 1 metastatic tumor, and 1 traumatic injury. The interval before the onset of mutism ranged from 0 to 168 h (mean 40.9 h). The mutism lasted from 1 to 168 days (mean 37.6 days). Subsequent dysarthria was present in 75 (80%) of the 93 patients. In this article, some specific recent illustrative reports are presented, and the concept of the role of the cerebellum in language and cognition is discussed. With these data as our point of departure, various hypotheses that have been advanced to explain the pathogenesis of this transient speech disorder are analyzed. The findings of the study suggest that the cause of the cerebellar mutism is the ischemia caused by vasospasm, as it usually developed after a latent period. 相似文献
8.
Administered a battery of test anxiety scales and 2 physiological measures to 25 undergraduates under 3 differing sets of demand characteristics in order to determine the effect of situational aspects on anxiety scale scores. Measures of academic performances were also obtained. The hypothesis that specific demand characteristics would differentially influence Ss' scoring on "trait" and "state" anxiety scales was supported, but no support for a hypothesized relationship between the operation of demand characteristics and systematic changes in the correlations between the anxiety scales and academic performance was found. Implications of findings for the construction and use of anxiety scales were discussed. (21 ref.) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
9.
G-protein-coupled receptors: molecular mechanisms involved in receptor activation and selectivity of G-protein recognition 总被引:1,自引:0,他引:1
J Wess 《Canadian Metallurgical Quarterly》1997,11(5):346-354
Asian students of seven Japanese language schools participated, and data of 292 Chinese, Taiwanese, and Korean students were analyzed in this study. They were asked about (1) attitudes toward their own and other cultures, (2) high regard for their country and culture, (3) self-efficacy and social skills at the moment and when they were in their country, (4) aspired level of social skills in this country, and (5) feeling of adjustment to life in Japan. Main findings were as follows: (1) psychological factors had stronger effects on the feeling than demographic factors. Self-efficacy in particular had a strong effect. (2) Attitudes to own and other cultures were related to self-efficacy and the feeling. (3) Structural analysis revealed a difference in the feeling between students from socialist and capitalist regions. Based on the analysis, a causal model was proposed of psychological and demographic factors leading to feeling of adjustment, and Asian students' adjustment to life in Japan was discussed in terms of adjustment to their inner, psychological environment. 相似文献
10.
Costa Paul Jr.; Terracciano Antonio; McCrae Robert R. 《Canadian Metallurgical Quarterly》2001,81(2):322
Secondary analyses of Revised NEO Personality inventory data from 26 cultures (N =23,031) suggest that gender differences are small relative to individual variation within genders; differences are replicated across cultures for both college-age and adult samples, and differences are broadly consistent with gender stereotypes: Women reported themselves to be higher in Neuroticism, Agreeableness, Warmth, and Openness to Feelings, whereas men were higher in Assertiveness and Openness to Ideas. Contrary to predictions from evolutionary theory, the magnitude of gender differences varied across cultures. Contrary to predictions from the social role model, gender differences were most pronounced in European and American cultures in which traditional sex roles are minimized. Possible explanations for this surprising finding are discussed, including the attribution of masculine and feminine behaviors to roles rather than traits in traditional cultures. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
11.
Evaluated the relation between "automatization" cognitive style and handedness, or degree of preferred-nonpreferred hand differentiation. 58 male undergraduates were tested on 8 cognitive tasks representing both automatized and nonautomatized abilities. After ipsatization of scores, 14 Ss were chosen as representing "strong automatization," and 14 Ss as "weak automatizers." All Ss were given 6 tests of manual performance using both preferred and nonpreferred hands. No differences were found between strong and weak automatizers in the degree of differentiation between overall preferred and nonpreferred hand performance. Explanations for these findings and the possible role of automatization cognitive style in hand differentiation in young children are discussed. (French summary) (15 ref.) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
12.
Culture, cross-role consistency, and adjustment: Testing trait and cultural psychology perspectives.
Church A. Timothy; Anderson-Harumi Cheryl A.; del Prado Alicia M.; Curtis Guy J.; Tanaka-Matsumi Junko; Valdez Medina José L.; Mastor Khairul A.; White Fiona A.; Miramontes Lilia A.; Katigbak Marcia S. 《Canadian Metallurgical Quarterly》2008,95(3):739
Trait and cultural psychology perspectives on cross-role consistency and its relation to adjustment were examined in 2 individualistic cultures, the United States (N = 231) and Australia (N = 195), and 4 collectivistic cultures, Mexico (N = 199), the Philippines (N = 195), Malaysia (N = 217), and Japan (N = 180). Cross-role consistency in trait ratings was evident in all cultures, supporting trait perspectives. Cultural comparisons of mean consistency provided support for cultural psychology perspectives as applied to East Asian cultures (i.e., Japan) but not collectivistic cultures more generally. Some but not all of the hypothesized predictors of consistency were supported across cultures. Cross-role consistency predicted aspects of adjustment in all cultures, but prediction was most reliable in the U.S. sample and weakest in the Japanese sample. Alternative constructs proposed by cultural psychologists-personality coherence, social appraisal, and relationship harmony-predicted adjustment in all cultures but were not, as hypothesized, better predictors of adjustment in collectivistic cultures than in individualistic cultures. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
13.
BB Tarbox BP Conroy ES Malicky FW Moussa DE Hockman JO Anglen WA Simpson EH Adelstein G Christensen BJ Gainor 《Canadian Metallurgical Quarterly》1998,(346):255-261
The efficacy of benzalkonium chloride was evaluated as an irrigating solution for the eradication of Staphylococcus aureus from a contaminated orthopaedic wound. Thirty Sprague Dawley rats were randomized into two groups. A stainless steel wire was placed in a lumbar spinous process, and the wound was inoculated with 10(7) or 10(6) colony forming units of Staphylococcus aureus. The wound was irrigated with 1 L of normal saline or 0.1% benzalkonium chloride solution. The animals were sacrificed, and cultures were obtained. Rats inoculated with 10(7) colony forming units of Staphylococcus aureus and irrigated with benzalkonium chloride had a significant decrease in the total number of positive cultures, deep wound cultures, and stainless steel wire cultures. Rats inoculated with 10(6) colony forming units of Staphylococcus aureus and irrigated with benzalkonium chloride also had a significant decrease in the total number of positive cultures, deep wound cultures, and stainless steel wire cultures. In a parallel noninoculation study, histologic evaluation of tissues did not show toxicity in the rats irrigated with benzalkonium chloride. This study shows that benzalkonium chloride is more effective than normal saline as an irrigating agent for eradicating Staphylococcus aureus from a contaminated orthopaedic wound. 相似文献
14.
Ouabain and concanavalin A, agents which bind to specific sites in the cell membrane, stimulate DNA synthesis and cell replication in monolayer cultures of neural retina cells from late chick embryos. The results suggest a relationship between control of retina cell replication and properties of the cell membrane. The experiments involved measurements of 3H-thymidine incorporation in primary monolayer cultures (24-48h) of retina cells from embryos of different ages. Stimulation by ouabain was greatest in cells from 14-day embryos, and its magnitude was similar to that elicited in these cell cultures by concanavalin A. Simultaneous treatment of 14-day retina cells with both agents resulted in a greater than additive stimulation of DNA synthesis. Our results demonstrated that, although during normal embryogenesis cell replication in the neural retina has virtually ceased by day 14 of development, some cells retained a capacity for mitogenesis when exposed to conditions such as provided in these experiments. By autoradiography the responding cells were identified as large epithelioid retina cells (LER cells). Under optimal conditions of simultaneous treatment with ouabain and Con A about 20% of the LER cells showed stimulation of DNA synthesis. The nature of LER cells and other aspects of our findings are discussed. 相似文献
15.
From 25 to 27 Sept 1997, a workshop was organized at the Essen Medical School (Universit?tsklinikum Essen), at which radiooncologists and jurists from universities and courts as well as lawyers contributed their views on mutual problems. The following topics were discussed by papers and in round table meetings: "Requirements on the patient's information", "definition of therapeutic guidelines-limits of clinical research and standard treatments", "treatment documentation", "liability of the physician for treatment faults" and "technical standard and preserve of quality". The consensual guidelines to the topics "patient's information", "therapeutic guidelines" and "liability" are presented here. 相似文献
16.
Conducted 3 experiments with a total of 131 male Wistar rats. Results indicate that (a) a single preexposure to a distinctive flavor resulted in both a retardation of aversion learning (if the flavor was later paired with toxicosis) and a preference for this flavor (if the flavor was not paired with toxicosis); (b) preexposure-induced preferences were retained over a 24-day period and were not attributable to thirst reduction consequent upon ingestion; and (c) Ss evidenced a preference for a preexposed solution by subsequently ingesting relatively great amounts of this solution when it was the only fluid available (as well as by choosing it over an alternative, simultaneously available solution). Results are discussed in terms of a "learned safety" interpretation of the deleterious effects of flavor preexposure on flavor-aversion learning. (27 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
17.
Robert Christopher; Probst Tahira M.; Martocchio Joseph J.; Drasgow Fritz; Lawler John J. 《Canadian Metallurgical Quarterly》2000,85(5):643
Although variations in national cultures predominate as explanations for the belief that universal approaches to management do not exist, there have been few reports of systematic studies. Data from employees of a single firm with operations in the United States, Mexico, Poland, and India were used to test the fit of empowerment and continuous improvement practices with national culture. Using the theoretical constructs of individualism–collectivism and power distance, the authors predicted that the practices would be more congruent in some cultures than in others and that value congruence would result in job satisfaction. Using structural equations modeling, the authors found that empowerment was negatively associated with satisfaction in India but positively associated in the other 3 samples. Continuous improvement was positively associated with satisfaction in all samples. Substantive, theoretical, and methodological implications are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
18.
Volunteer Ss were placed in 3 experimental therapy situations talking to: a tape recorder; a therapist who would respond on a nonverbal level only; and a regular therapeutic situation, nondirectively oriented. The degree of manifest (GSR) and reported anxiety was obtained as well as ratings re the patient's tendency to approach meaningful areas of discussion and amount of associated affect. Over a period of 5?hr. sessions, the "regular" group showed a tendency to approach more affectively-laden content and to experience more anxiety with the initial approach, but overall anxiety reduction. "Tape" and "nonverbal" group results were discussed and compared. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
19.
FAN Jinping PING Zhongyuan XU Enjun PAN Bingbing CHE Daidi 《Canadian Metallurgical Quarterly》2011,18(1)
The effects of the microspore developmental stage, hormones and culture condition on anther in vitro culture of lily (Lilium spp.) were discussed. The results showed that when the flower buds were about 23-26 mm long, the microspores were at the uninucleate stage wluch was suitable for culture and the culture under the darkness would promote the callus induction of anther. The induction frequency could reach 42.5% in the optimized medium which was MS+[6-BA(0.5)+KT(2.0)+2,4-D(1.0)]mg·L-1.The rate of callus differentiation could reach 31.57% in the optimized medium wluch was MS+NAA(1.5,2.0)mg·L-1. 相似文献
20.
GW Ajello GM Matar B Swaminathan WF Bibb LO Helsel BA Perkins 《Canadian Metallurgical Quarterly》1995,30(6):345-349
Brazilian purpuric fever (BPF) is a highly fatal pediatric disease that may follow an episode of purulent conjunctivitis caused by a virulent clone of Haemophilus influenzae biogroup aegyptius (Hae). Oral rifampin prophylaxis, by eliminating carriage of the BPF clone in children with conjunctivitis, may prevent onset of the systemic disease. A test to detect the BPF clone directly from eye swabs could identify those in need of prophylaxis. This is a preliminary report of a rapid dot immunoassay performed on a "flow-through" cartridge that was developed for use under field conditions. The test is based upon recognition of a unique epitope of the 25-kDa pilin protein on the surface of BPF clone cells by a monoclonal antibody. With 36 laboratory-maintained cultures of Hae (15 clone isolates and 21 others), sensitivity of the assay was 67% and specificity was 95%. When fimbrial-enriched (25-kDa+) phenotypes of five false-negative clone strains were prepared for use as test antigens, sensitivity rose to 100%. Evaluation of the immunoassay under field conditions is necessary to prove its efficacy. 相似文献