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排序方式: 共有1433条查询结果,搜索用时 11 毫秒
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Smoking and raven IQ 总被引:1,自引:0,他引:1
Nicotine has recently been shown to enhance measures of information processing speed including the decision time (DT) component of simple and choice reaction time and the string length measure of evoked potential waveform complexity. Both (DT and string length) have been previously demonstrated to correlate with performance on standard intelligence tests (IQ). We therefore hypothesised that nicotine is acting to improve intellectual performance on the elementary information processing correlates of IQ. In the current experiment we tested this hypothesis using the Raven Advanced Progressive Matrices (APM) test. APM scores were significantly higher in the smoking session compared to the non-smoking session, suggesting that nicotine acts to enhance physiological processes underlying performance on intellectual tasks. 相似文献
3.
Clinical trial of a prevention and treatment protocol for skin breakdown in two nursing homes. 总被引:1,自引:0,他引:1
Susan Hunter Julie Anderson Darlene Hanson Patricia Thompson Diane Langemo Marilyn G Klug 《Journal of wound, ostomy, and continence nursing》2003,30(5):250-258
OBJECTIVE: Our objective was to assess the effectiveness of skin care protocols, including a body wash and skin protectant, on skin breakdown in 2 nursing homes. DESIGN: This was a quasi-experimental pretest/posttest design study.Setting and subjects Adult residents (n = 136) of 2 skilled nursing homes consented to participate in this study. Seventy percent were women; the sample average age of 82 years. INSTRUMENTS: A researcher-designed data recording form documented resident demographics, incidence and type of skin breakdown or pressure ulcer, presence of urinary or fecal incontinence, and assessment of the effectiveness of body wash and skin protectant. METHODS: Baseline data on prevalence of pressure ulcers and skin protocol were collected weekly for a 3-month period followed by a week-long educational program by the researchers about skin care and the body wash and skin protectant. During the 3-month trial with the body wash and skin protectant incorporated into routine care, research assistants recorded resident data weekly and researchers again assessed prevalence and incidence of pressure ulcers and skin breakdown weekly. RESULTS: Incorporation of a body wash and skin protectant into a skin care prevention and early intervention protocol in 2 nursing homes documented a decrease in skin breakdowns from 68 pre-intervention to 40 postintervention; the decrease in agency B was statistically significant. There was a statistically significant decrease in stage I and II pressure ulcer incidence overall (pre-intervention = 19.9%, postintervention = 8.1%). Nurses evaluated the body wash and skin protectant as effective for 98% of the time used. CONCLUSION: Implementation of a protocol for skin care along with staff education, including the prophylactic use of a body wash and skin protectant, reduced the incidence of skin breakdown, including pressure ulcers and perineal dermatitis, in 2 long-term care facilities. 相似文献
4.
J. E. Herrmann Dorothy M. Perron-Henry Darlene Stobbs-Walro N. R. Blacklow 《Archives of virology》1987,94(3-4):259-265
Summary We have prepared monoclonal antibodies to each of the enteric adenoviruses types 40 and 41. Three different hybridoma cell lines were selected which produced antibody found to react by radioimmunoprecipitation with adenovirus (Ad) hexon antigens. One was specific for Ad 40, another for Ad 41, and a third one reacted with both types. When tested in an enzyme immunoassay against all 41 known human Ad types, the type-specific monoclonal antibody against Ad 40 reacted homotypically, as did the monoclonal antibody against Ad 41. In addition, these monoclonal antibodies neutralized the homologous enteric Ad type. The monoclonal antibody which reacted with both enteric Ad types also showed lower levels of reactivity with the group C adenoviruses types 2, 5, and 6. The monoclonal antibodies produced will provide a definitive means for rapid identification of specific Ad types, and will be useful in defining the relationship of enteric adenoviruses to other types. 相似文献
5.
Petra C. Arck David A. Ferrick Darlene Steele-Norwood Ken Croitoru David A. Clark 《American journal of reproductive immunology (New York, N.Y. : 1989)》1997,37(1):87-93
PROBLEM: T cells are present at the feto-maternal interface, but their function during pregnancy has not been fully elucidated. T cells bearing γλ T-cell receptor (TCR) may be particularly important, as some subsets can react to trophoblast cells by producing cytokines, such as interleukin-2 (IL-2). METHOD: We depleted T cells bearing the γλ receptor by injecting monoclonal antibodies (mAB) into females of the abortion-prone animal model CBA x DBA/2. We investigated the percentage and number of γλ T-cell receptor positive (TCR)+ cells in decidua and spleen during pregnancy in control and γλ-depleted female mice. Pregnant females were also exposed to ultrasonic sound stress to boost the abortion rate. RESULTS: Stress failed to increase the abortion rate in the γλ TCR-depleted mice. FACScan analysis show that the ratio of cells bearing the γλ TCR dramatically decreased after injection of mAB to the γλ TCR in spleen and decidua, these cells recovered six days after depletion, showing a change in cytokine pattern. Levels of TNF-α in decidual γλ T cells decreased; similar effects of decreasing Th1 cytokines could be observed in splenic γλ T cells. We further identified increased levels of intracellular TNF-α in the Vλ4 subset in the decidua, compared to spleen. CONCLUSIONS: Trophoblast recognition by the Vλ4 T-cell subset in the decidua may cause the release of abortogenic cytokines such as TNF-α. Depletion of such γλ TCR T cells during early pregnancy may promote successful pregnancy outcome in normal pregnancy and prevent stress-induced abortions. 相似文献
6.
In the pars distalis of the pituitary gland in adult and embryonic dwarf (dw/dw) mutant mice, ambiguous cells exhibiting ultrastructural features common to growth hormone (GH) cells and prolactin (Prl) cells were analyzed by means of colloidal gold ultrastructural immunocytochemistry in order to define the functional nature of these peculiar cells. Adult and 18-day embryonic pituitaries from normal (+/+; dw/+) and dwarf (dw/dw) mice were processed with antibodies to GH, Prl, TSH (thyroid-stimulating hormone), ACTH (adrenocorticotropic hormone), LH (luteinizing hormone), FSH (follicle-stimulating hormone), and HCG (chorionic gonadotropic hormone). In the adult and embryonic dwarf pituitaries, the ambiguous cells reacted negatively to all of the antibodies except for anti-ACTH, which labeled them well. In addition, the ACTH-positive cells showed a much wider variety of shapes and granule size and distribution, as compared with normal adults. In the embryos, this variability in ACTH cell morphology occurred not only in dwarf embryos, but in their normal counterparts as well. The results thus suggest that adult dwarf pituitaries may retain an embryonic or incompletely differentiated form of ACTH cells. © 1993 Wiley-Liss, Inc. 相似文献
7.
Summary Immunofluorescence and colloidal gold immunocytochemistry were used to analyze the regional distribution of adrenocorticotropic (ACTH) cells and their ultrastructural relationship with growth hormone (GH) cells in adult and 17-day embryonic little (lit/lit) mice that exhibit GH cell defects. Adult lit/lit pituitaries lack the distinctive regionalization of ACTH cells that characterizes normal pituitaries, although typical ultrastructural relationships occur between some ACTH and GH cells. In 17-day embryos, normal and lit/lit pituitaries show similar distributions of ACTH cells. However, in lit/lit pituitaries the pars distalis cells are more loosely arranged, with poorly defined clusters and cords, than in normal glands. The results indicate that whereas the lack of ACTH cell regionalization in adult glands may be a secondary effect of the GH cell defect, the differences in overall integrity of the 17-day embryonic glands suggest the possibility of a developmental disturbance during early stages of gestation in this mutant.Supported by research grant No. HD12308 from the National Institute of Child Health and Human Development, National Institutes of Health (USA) 相似文献
8.
Randomized placebo-controlled study of low-dose warfarin for the prevention of central venous catheter-associated thrombosis in patients with cancer. 总被引:13,自引:0,他引:13
Stephen Couban Michael Goodyear Margot Burnell Sean Dolan Parveen Wasi David Barnes Darlene Macleod Erica Burton Pantelis Andreou David R Anderson 《Journal of clinical oncology》2005,23(18):4063-4069
PURPOSE: In this multicenter, randomized, placebo-controlled clinical trial, we studied whether warfarin 1 mg daily reduces the incidence of symptomatic central venous catheter (CVC) -associated thrombosis in patients with cancer. PATIENTS AND METHODS: Two hundred fifty-five patients with cancer who required a CVC for at least 7 days were randomly assigned to receive warfarin 1 mg or placebo. RESULTS: There were 11 (4.3%) symptomatic CVC-associated thromboses among 255 patients, with no difference in the incidence of symptomatic CVC-associated thrombosis between patients taking warfarin 1 mg daily (six of 130 patients; 4.6%) and patients taking placebo (five of 125 patients; 4.0%; hazard ratio, 1.20; 95% CI, 0.37 to 3.94). Warfarin had no effect on CVC life span (84 days v 63 days in control and warfarin groups, respectively; 95% confidence limit, -16 to 55 days; P = .09), and it did not affect the number of premature CVC removals (23.2% v 25.4% in control and warfarin groups, respectively; 95% confidence limit of difference -8.34 to 12.71; P = .68) or the frequency of major bleeding episodes (2% v 0% in control and warfarin groups, respectively; P = .5, Fisher's exact test). CONCLUSION: Symptomatic CVC-associated thrombosis in patients with cancer, although significant, is less common than previously reported. In this study, the administration of warfarin 1 mg daily did not reduce the incidence of symptomatic CVC-associated thrombosis in patients with cancer. However, the low rate of symptomatic CVC-associated thrombosis means that a much larger trial is required to address this issue definitively. 相似文献
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10.
Stough C Downey LA Lloyd J Silber B Redman S Hutchison C Wesnes K Nathan PJ 《Phytotherapy research : PTR》2008,22(12):1629-1634
While Ayurvedic medicine has touted the cognitive enhancing effects of Bacopa monniera for centuries, there is a need for double-blind placebo-controlled investigations. One hundred and seven healthy participants were recruited for this double-blind placebo-controlled independent group design investigation. Sixty-two participants completed the study with 80% treatment compliance. Neuropsychological testing using the Cognitive Drug Research cognitive assessment system was conducted at baseline and after 90 days of treatment with a special extract of Bacopa monniera (2 x 150 mg KeenMind) or placebo. The Bacopa monniera product significantly improved performance on the 'Working Memory' factor, more specifically spatial working memory accuracy. The number of false-positives recorded in the Rapid visual information processing task was also reduced for the Bacopa monniera group following the treatment period. The current study provides support for the two other published studies reporting cognitive enhancing effects in healthy humans after a 90 day administration of the Bacopa monniera extract. Further studies are required to ascertain the effective dosage range, the time required to attain therapeutic levels and the effects over a longer term of administration. 相似文献