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1.
In 2 consecutive laboratory studies using virtually identical methods, undergraduate Ss (45 and 133 Ss for Studies 1 and 2, respectively) completed the Group Embedded Figures Test in group sessions. They then performed an assembly task in a laboratory setting and completed a measure designed to assess the "immediate" and "projected" perceptions of task characteristics. Results of Study 1 show significant correlations between field independence and immediate perceptions of variety, task identity, and feedback. These results were replicated in Study 2. In addition, Study 2 revealed significant correlations between field independence and (a) immediate perceptions of interaction and (b) projected perceptions of variety and interaction. Results suggest that field independence may be a determinant of individuals' perceptions of task characteristics. (13 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   

2.
The coagulation activity of plasma phospholipid membranes (PM) was measured in plasma depleted for platelets (PDP) in 50 normal subjects and 33 patients with the antiphospholipid syndrome (APS) and the "lupus anticoagulant" in the plasma. The normal value for phospholipid activation of clotting was 99.8 +/- 3.5% (from 75 to 125%), whereas in patients with APS and lupus anticoagulant it was 42.1 +/- 8.2% (p < 0.001). Addition of PM from patients' PDP to normal plasma free from PM did not normalize clotting. Addition of PM from normal plasma to patients' PDP normalized the clotting time. Therapy with discrete plasmapheresis increased the phospholipid activation value in the patients from 42.1 to 73.3% (p < 0.01), which was due to removal of the PM-antiphospholipid antibody complex from PDP. The proposed microfiltration method can be used in the complex of tests for detecting the lupus anticoagulant in patient's plasma.  相似文献   

3.
Interstitial lung disease (ILD) is a complication of polymyositis (PM) and dermatomyositis (DM). It often manifests itself in association with myositis-specific antisynthetase autoantibodies, among which anti-Jo-1 antibodies are the most commonly encountered. In contrast, ILD associated with anti-Jo-1 antibodies without muscle involvement is rare and not well characterized. We report four patients presenting with ILD associated with anti-Jo-1 antibodies. Histological findings of transbronchial biopsies disclosed a pattern consistent with nonspecific interstitial pneumonitis, a CD8+ lymphocytosis was found in bronchoalveolar lavage. Only one of these patients developed an "antisynthetase syndrome" with PM, after nearly 2 yrs of severe ILD. The clinical conditions of all four cases showed stabilization or improvement when cyclosporine was added to their immunosuppressive treatment. These cases confirm that a CD8+ lymphocytic interstitial lung disease may be the first, and sole manifestation of autoimmune disease associated with anti-Jo-1 antibodies. Furthermore, they suggest that this form of interstitial lung disease apparently has a poor response to steroids and cytotoxic drugs, but may respond to moderate doses of cyclosporine and azathioprine in addition to low doses of steroids.  相似文献   

4.
The sperm plasma membrane is segregated into functionally, biochemically, and structurally distinct domains yet the protein sorting pathways and assembly mechanisms that assemble these domains during spermiogenesis are incompletely understood. We previously characterized two structurally related size-variant, integral membrane proteins of 52 kDa (PM52) and 35 kDa localized to the periacrosomal plasma membrane of guinea pig cauda epididymal spermatozoa (Westbrook-Case et al., 1994). In this study we used light and electron microscopic immunocytochemistry to define the expression pattern and sorting pathway that establishes the domain-specific distribution of PM52 during spermiogenesis. The PM52 is first expressed in acrosome-phase spermatids and it localizes exclusively to the cytoplasmic lobe. Immunoelectron microscopy revealed that both cytoplasmic vesicles and the plasma membrane of the cytoplasmic lobe labeled with anti-PM52. During early stages of expression, PM52 appeared to be absent from the head region, but significant PM52 accumulation over the spermatid head was noted in late acrosomal phase spermatids. Throughout spermiogenesis PM52 extended posteriorly to the annulus, which represents a barrier preventing PM52 diffusion into the posterior tail. Following the migration of the annulus to the midpiece-principal piece junction, PM52 began to disappear from the flagellar region and at the completion of spermiogenesis most of the PM52 was restricted to the acrosomal segment. Spermatids and epididymal sperm PM52 exhibited identical sizes by SDS-PAGE and immunoblotting, indicating that they are not proteolytically modified during epididymal maturation. The PM52 antibodies were also used to screen a guinea pig testis cDNA library, and sequence determination of full-length PM52 clones demonstrated identity of a sperm membrane protein recently termed "sperad" (Quill and Garbers, 1996). Membrane barriers and potential mechanisms establishing the domain-specific residence of PM52 are discussed.  相似文献   

5.
Examined mother–child emotion-related interactions and how these interactions related to mothers' perceptions of children's emotional reactivity. Mothers of 49 kindergartners and 54 2nd graders told their children 2 stories about distressed others. Children's emotional, physiological, and prosocial responses were also obtained. Mothers rated children's tendencies to become emotional when exposed to distressed others. For kindergartners, mothers' perceptions of children's emotional reactivity were positively related to her use of positive facial expressions. Mothers' perceptions of 2nd graders' emotional reactivity were inversely related to maternal responsiveness. These findings suggest that mothers may "adjust" their interactions with their children based on their perceptions of children's emotional tendencies. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   

6.
The lamellar spacing dl of purple membrane (PM) multilayer systems was investigated with neutron diffraction as a function of temperature and of the level of hydration. The observed large T-dependent variations of dl indicate that PM is partially dehydrated when cooled below a "hydration water freezing point". This phenomenon is reversible, but a hysteresis is observed when PM is rehydrated upon reheating. The hydration water remaining bound to the membrane below about 240 K is non-freezing. Its amount was found to be hnf=0.24(+/-0.02) g 2H2O/g BR for all samples equilibrated at room temperature in the presence of 2H2O vapour at >/=84% r.h. It is evident, that the dehydration/rehydration behaviour of PM is strongly correlated with the temperature-dependent behaviour of the dynamical structure factor. Above the well-known "dynamical transition" announcing the onset of localized diffusive molecular motions between 190 K and 230 K, a second dynamical transition is caused by the temperature-induced rehydration of the PM starting near 255 K. This is also correlated with the deviation from a pure Arrhenius law of the rate-limiting process in the photocycle, known to occur upon cooling beyond the ice point into the same temperature region. Our results suggest that the phenomenon of dehydration and rehydration induced by cooling and reheating, respectively, is a general property of biological membranes.  相似文献   

7.
The effect of delay on prospective memory (PM) is mixed. Research has typically shown that PM either decreases or remains unchanged as the time increases between intention formation and encounter with a PM cue. However, the results of one study demonstrated that PM sometimes increases with increasing delays (Hicks, Marsh, & Russell, 2000). Hicks et al. hypothesised that increasing the delay may afford an opportunity for people to spontaneously rehearse the intention, or to be reminded of the intention. In the present work, we tested delays of 6 minutes, 21 minutes, and 36 minutes. Two factors were orthogonally manipulated between-subjects. One was the duration of the filler task that came between intention formation and the beginning of the ongoing task in which PM cues were embedded. The second was the duration of the ongoing task prior to the presentation of the first PM cue. Lengthening the ongoing task delay decreased PM. However, lengthening the filler task nominally increased PM. These results suggest that delays within the ongoing task replicate the effects traditionally found in retrospective memory work. In contrast, delays between intention formation and the beginning of the ongoing task may not have straightforward effects on PM retrieval. (PsycINFO Database Record (c) 2011 APA, all rights reserved)  相似文献   

8.
Objective: In a recent study, performance on a certain kind of prospective memory task (PM), labeled focal PM, was sensitive to the very early stages of Alzheimer's disease (AD; Duchek, Balota, & Cortese, 2006). This study sought to replicate and extend these findings by investigating both focal and nonfocal PM, as well as possible influences of alleles of the apolipoprotein E (ApoE) gene. Method: Thirty-five healthy older adults and 33 adults in the very earliest stages of AD, as determined by the clinical dementia rating scale, completed both focal and nonfocal PM tasks. Performance on these tasks has been linked to qualitatively different cognitive processes (Scullin, McDaniel, Shelton, & Lee, 2010), thereby providing leverage to illuminate the specific processes that underlie PM failures in very early AD. Approximately half of the adults in each group were ApoE e4 carriers and half were noncarriers. We also obtained participants' scores on a battery of standard psychometric tests. Results: There was a significant interaction between the type of PM task and dementia status, p p2 = .12, demonstrating that the AD-related decline was more robust for focal than for nonfocal PM. Further, focal PM performance significantly discriminated between the very earliest stages of AD and normal aging, explaining variance unique to that explained by typical psychometric indices. ApoE status, however, was not associated with PM performance. Conclusion: The pronounced deficit observed in the focal PM task suggests that spontaneous retrieval processes may be compromised in very early AD. (PsycINFO Database Record (c) 2011 APA, all rights reserved)  相似文献   

9.
Polymyositis (PM) and dermatomyositis (DM) may be associated with motor dysfunction of the entire gastrointestinal tract. Abnormal esophageal motor function is a well-recognized complication of these diseases. In this study, we used a solid phase esophageal study to evaluate the motor function in patients with PM or DM. Twenty-three patients and 36 age-matched normal volunteers were studied. Each subject was placed in a supine position above a gamma camera linked to a computer and was given a 4-ml bolus of solid gelatin containing 1 mCi of Tc-99m phytate. Data were acquired in the list mode. A computer method modified from Kelim and Wald and Russell et al. was used to calculate the following: A) total mean transit time (MTT); B) residual fraction after the first swallow (RF); and C) retrograde index (RI). All values are presented as mean +/- standard deviation (SD). The Student's t-test was used to test statistical significance. Our preliminary results suggest: 1) delayed esophageal emptying is common (17/23) in PM/DM, indicating frequent malfunction of the smooth muscle of the upper gastrointestinal tract in PM/DM and 2) measurement of esophageal motility may monitor disease activity in PM/DM.  相似文献   

10.
Polymyositis and dermatomyositis (PM/DM) without creatine kinase (CK) elevation shows a poor prognosis. PM/DM is complicated with interstitial lung disease (ILD), some of which progress rapidly. To clarify the clinical features of PM/DM from the viewpoint of ILD progression, the clinical data of 25 PM/DM patients with ILD were reviewed. They were classified as responders or non-responders. The patients whose ILD responded to steroid therapy and elicited good clinical courses were termed as responders. On the other hand, the patients who had rapidly progressive ILD resistant to steroid therapy were considered as non-responders. The patients diagnosed to have DM were likely to be steroid-resistant. The non-responder group revealed significantly high aspartate aminotransferase (AST), low CK, low white blood cell (WBC), and low absolute lymphocyte counts in their peripheral blood. High CK/AST may be a favorable predictor of the disease. The percentages of lymphocytes in bronchoalveolar lavage fluid were increased in both groups. However, the percentages of two responders with low CK/AST were lower than those of three non-responders. A steroid-resistant ILD group with PM/DM may be clinically different from a steroid-responsive ILD group.  相似文献   

11.
Young (ages 18–22 years) and older (ages 61–87 years) adults (N = 106) played the Virtual Week board game, which involves simulating common prospective memory (PM) tasks of everyday life (e.g., taking medication), and performed working memory (WM) and vigilance tasks. The Virtual Week game includes regular (repeated) and irregular (nonrepeated) PM tasks with cues that are either more or less focal to other ongoing activities. Age differences in PM were reduced for repeated tasks, and performance improved over the course of the week, suggesting retrieval was more spontaneous or habitual. Correlations with WM within each age group were reduced for PM tasks that had more regular or focal cues. WM (but not vigilance) ability was a strong predictor of irregular PM tasks with less focal cues. Taken together, these results support the hypothesis that habitual and focally cued PM tasks are less demanding of attentional resources (specifically, WM), whereas tasks that are more demanding of controlled attentional processes produce larger age differences, which may be attributable to individual differences in WM. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   

12.
Osmotically hemolysed pigeon erythrocytes retain a considerable part of the total cell content of aldolase activity. After washing off the ghosts from hemoglobin and removing the nuclei, a considerable portion of aldolase activity is found in the supernatant. The retained part of aldolase is rather firmly bound to plasma membranes (PM), as evidenced by the fact, that double washing with a mixture of 0.3 M sucrose, 0.01 M tris-HCl (pH 7.4) and 0.004 M MgCL2, or with 0.15 M NaCl or H2O does not appreciably decrease the aldolase activity of PM. Only washing of PM with 0.5 M NaCl results in appreciable decrease of aldolase retention by PM. The binding of aldolase proved to be temperature sensitive: after heating the binding of aldolase to PM specifically decreased. These data suggest that the interaction of the enzyme with PM of pigeon erythrocytes occurs in the intact cell and may be of physiological significance.  相似文献   

13.
In a prospective study of pregnant women (n = 36) in four southern Manitoba First Nations communities to test a breastfeeding decision-making model, maternal perceptions of the impact of referents (individuals and groups which impact a woman's decisions) was measured. A quantitative "referent score" comprised of a measure of the referent's "breastfeeding-supportiveness" and a measure of maternal compliance with the referent. The woman's own mother, the community health nurse, and the physician were perceived as highly supportive of breastfeeding, and as people with whom the woman was most likely to comply. Women also identified the timing of their infant feeding decisions, as reported in the third trimester of pregnancy. Only 22% had decided prior to pregnancy. During the third trimester, 36% did not know their infant feeding choice. Women forced to verbalize a "choice" prior to being informed may make decisions based on the perceived cultural norm, which may be bottle feeding. A neutral attitude by health professionals may be harmful if it prevents informed choice by pregnant or postpartum clients. Prenatal education of the pregnant woman with her own mother, and adolescent school education of the peer group (sisters, close friends and male partner) may need to be incorporated into a community strategy to promote breastfeeding.  相似文献   

14.
15.
Prospective memory (PM) reflects the product of cognitive processes associated with the formation, retention, delayed initiation, and execution of intentions. It has been proposed that developmental changes in PM across the lifespan are heavily dependent upon the developmental trajectory of executive control functions. This study is the first to apply a complex PM task to children, young adults, and older adults. The procedure allows for the assessment of each of the 4 phases of PM. During intention execution, the authors additionally manipulated whether participants had to actively interrupt attention to the current 'ongoing' task in order to switch to the execution of the next intended task. Group differences mirroring inverted U-shaped functions were observed in those phases conceptualized as relying on executive control (intention formation, initiation, and execution). Age differences in intention execution were substantially greater when active task interruption was necessary. The current study provides the first evidence of growth and decline of complex PM across the lifespan and suggests that the degree of inhibitory control needed to succeed in the task may be one factor underlying this development (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   

16.
Adoptive immunotherapy with interleukin-2 and tumor-infiltrating lymphocytes (TIL) is rarely effective in primary lung cancer. We hypothesize that pulmonary macrophages (PM), which are increased substantially in the lungs of smokers, might suppress TIL function. The addition of PM into the TIL cytotoxicity assay produced a concentration-dependent suppression of TIL cytotoxicity with up to 71% inhibition of autologous tumor killing at the 1:1 PM:TIL ratio. Inhibition was not target-specific, as killing of NK-sensitive (K562), NK-resistant (M14), and autologous tumor targets were equally suppressed. Nor was inhibition specific for lung TIL, as similar inhibition was observed with melanoma and renal TIL. Using a model system, we demonstrated that both CD3+ antigen-specific and CD56+ nonspecific lymphocytes are susceptible to the suppressive effects of the PM. Direct co-incubation of PM and TIL for 4 to 44 h resulted in progressive suppression of TIL proliferation and cytotoxicity. TIL cytotoxicity remained suppressed even if PM were removed from the co-culture after 24 h, but was restored if the separated TIL were re-incubated in interleukin-2. These results suggest that PM may locally regulate the proliferative and cytotoxic function of adoptively transferred TIL.  相似文献   

17.
The present study, a secondary analysis of published data (B. Hitsman et al., 1999), assessed (a) the influence of initial positive mood (PM) on smoking cessation and (b) whether smokers low in PM benefited from fluoxetine versus placebo for cessation. Euthymic adult smokers (N = 103) received 10 weeks of cessation treatment. Analyses showed a Time × PM interaction, indicating that higher baseline PM predicted decreased abstinence during treatment but increased abstinence afterward, mediated by time to dropout. Dichotomous initial PM interacted with drug, suggesting a benefit of fluoxetine for low-PM smokers. Results indicate that lower pretreatment PM may inhibit long-term cessation. Smokers with lower baseline PM may benefit from treatment that increases PM. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   

18.
OBJECTIVE: To determine whether the "spot" method of determining fractional excretion (FE) of electrolytes in cats is accurate. ANIMALS: 5 clinically normal young adult female cats. PROCEDURE: Cats were acclimated to metabolism cages, and 2 consecutive 72-hour collections of urine were made to determine FE of total calcium, potassium, total magnesium, sodium, and phosphorus by conventional methods, using endogenous creatinine clearance as an estimate of glomerular filtration rate. During collections, small samples of urine were obtained by cystocentesis at 8 AM, 3 PM, and 9 PM for determination of FE of the electrolytes by use of the "spot" method. RESULTS: Values from "spot" determinations were highly variable, compared with 72-hour values, with a high percentage falling outside the range of mean +/- 2 SD for 72-hour FE values. CONCLUSIONS AND CLINICAL RELEVANCE: The "spot" method for determining FE is not precise, and if used, caution and judgement should be exercised in interpretation of the results.  相似文献   

19.
100 nurses were observed for burnout and depressive symptomatology. Analysis of change scores and structural equations suggested that the variance shared by burnout and depression (20%) may be attributable to their codevelopment. A definitive temporal sequence among measures of burnout and depressive affect was not obtained. At initial assessment and follow-up, burned-out nurses displayed accurate perceptions of job uncontrollability, whereas non-burned-out nurses overestimated job control. Perceptual accuracy increased in linear fashion with degree of burnout, irrespective of depressive symptomatology. Frequency of threats to job control predicted a significant amount of the variance in perceptual accuracy, supporting the view that "burnout realism" is reality driven. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   

20.
OBJECTIVES: Environmental particles < 10 microns average aerodynamic diameter (PM10) are associated with mortality, exacerbation of airways diseases, and decrement in lung function. It is hypothesised that PM10 particles, along with other pathogenic particles, generate free radicals at their surface in reactions involving iron, and that this is a factor in the pathogenicity of PM10 particles. Identification of free radical activity in PM10 and examination of the content and role of iron in this process was undertaken. METHODS: Free radical activity was detected with a supercoiled plasmid, phi X174 RF1 DNA, and measured as scission of the supercoiled DNA (mediated by free radicals) by scanning laser densitometry. The role of the hydroxyl radical was confirmed by the use of the specific scavenger mannitol, and the role of iron investigated with the iron chelator desferrioxamine-B (DSF-B). Iron released from PM10 particles at pH 7.2 and pH 4.6 (to mimic conditions on the lung surface and in macrophage phagolysosomes, respectively) was assessed spectrophotometrically with the Fe++ chelator ferrozine and the Fe+ + + chelator DSF-B. RESULTS: PM10 particles showed significant free radical activity by their ability to degrade supercoiled DNA. A substantial part of this activity was due to the generation of hydroxyl radicals, as shown by partial protection with mannitol. Similarly, DSF-B also conferred protection against the damage caused to plasmid DNA indicating the role of iron in generation of hydroxyl radicals. Negligible Fe++ was released at either pH 7.2 or pH 4.6 by contrast with Fe+ + +, which was released in substantial quantities at both pHs, although twice as much was released at pH 4.6. CONCLUSIONS: PM10 particles generate the hydroxyl radical, a highly deleterious free radical, in aqueous solution. This occurs by an iron dependent process and hydroxyl radicals could play a part in the pathogenicity of PM10 particles. Iron release was greatest at the pH of the lysosome (pH 4.6) indicating that iron may be mobilised inside macrophages after phagocytosis, leading to oxidative stress in the macrophages.  相似文献   

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