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排序方式: 共有653条查询结果,搜索用时 15 毫秒
1.
Beth T McCreary Thomas E Joiner Norman B Schmidt Nicholas S Ialongo 《Journal of clinical child and adolescent psychology》2004,33(2):313-324
This study examined the structure and symptom correlates of perfectionism in a sample of 6th-grade, urban, African American children using the Child and Adolescent Perfectionism Scale (CAPS; Flett, Hewitt, Boucher, Davidson, & Munro, 2000). Confirmatory factor analysis showed inadequate fit of the original subscales. Exploratory factor analysis suggested 3 dimensions of perfectionism: A Socially Prescribed and a Self-Oriented-Critical factor were described as maladaptive, whereas a Self-Oriented-Striving factor was proposed as adaptive. Cross-sectional correlations among the perfectionism dimensions and symptoms of psychopathology fit well with the adaptive versus maladaptive model. In addition, Socially Prescribed Perfectionism showed a robust predictive relation to 7th-grade internalizing symptoms, especially depression, in boys. Results are discussed in the context of the cultural and socioeconomic characteristics of this African American sample and suggestions for future research are provided. 相似文献
2.
The role of complement in host resistance to bacteria 总被引:9,自引:0,他引:9
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K. A. Joiner J. A. Gelfand J. G. Bartlett S. L. Gorbach 《International journal of experimental pathology》1981,62(3):222-226
We have used a recently developed model for s.c. abscess formation to study the effect of corticosteroids on abscess formation in mice. Mice were given daily i.p. injections of either hydrocortisone, 20 mg/kg/day or dexamethasone, 0.8 mg/kg/day, starting 3 days before inoculation with Staph, aureus and continuing for the duration of the experiment. Another group of mice was given a single injection of dexamethasone, 8 mg/kg, 1 h after inoculation with Staph. aureus. Encapsulated abscesses developed in all animals by Day 4, and there was no mortality. Abscess volume +/- s.l. mean at 4 days was reduced (p less than 0.0005) from 39.9 +/- 3.0 mm3 in controls to 16.7 +/- 3.6 mm3 in the daily dexamethasone group. Abscess volume at 4 days after a single dose of dexamethasone was 39.9 +/- 8.0 mm3. Bacterial concentrations per ml of pus were equivalent in all groups (10(10,6)-10(10.9). The effect of steroids on formation of sterile abscesses was also studied. Abscess volumes were smaller in animals given daily hydrocortisone or dexamethasone when compared to controls, but the difference was significant only for mice receiving daily hydrocortisone. These results suggest that prolonged high-dose steroid administration decreased the magnitude of the acute inflammatory reaction responsible for abscess formation in the soft tissue but did not interfere significantly with the process of containment and encapsulation of s.c. abscesses. A single massive dose of steroid did not influence abscess formation. 相似文献
5.
Cummins RJ Mothersill C Seymour CB Johns H Joiner MC 《International journal of radiation biology》1999,75(2):225-232
PURPOSE: To investigate the effect of irradiating microcolonies of various sizes on their subsequent ability to form colonies. MATERIALS AND METHODS: The location of individual HPV-G cells in tissue culture flasks was recorded using computerized microscopy. This allowed the cells' positions to be continually revisited, which enabled manual sizing of individual microcolonies both at the time of irradiation (between 0-5 Gy) and following an incubation period during which the microcolonies were assessed for cologenic survival. RESULTS: The experiments indicate that when irradiated as microcolonies, cells have plating efficiencies (PE) that are lower than expected when compared with the prediction from the PE values of cells irradiated individually. CONCLUSION: These data support the conclusions of Mothersill and Seymour (1997b) which challenge the concept of independent survival of certain types of cells following irradiation. The results indicate that interactions between cells can occur even in small aggregates. 相似文献
6.
This article describes how the goal programming methodology was applied to a state level Crippled Children's Program. The various organizational goals are incorporated into the programming model to indicate the trade-offs associated with the resource allocation process. Alternative allocations are presented in terms of a "what if" approach to programming. 相似文献
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S. C. Short J. Kelly C. R. Mayes M. Woodcock M. C. Joiner 《International journal of radiation biology》2013,89(6):655-664
Purpose : It was demonstrated previously that some radioresistant tumour cell lines respond to decreasing single, low radiation doses by becoming increasingly radiosensitive. This paper reports the response of four radioresistant human glioma cell lines to multiple low-dose radiation exposures given at various intervals. Three of the cell lines (T98G, U87, A7) were proven already to show low-dose hyper-radiosensitivity (HRS) after single low doses; the fourth, U373, does not show HRS after acute doses. Materials and methods : Clonogenic cell-survival measurements were made in vitro using the Dynamic Microscopic Image Processing Scanner (DMIPS) or Cell Sorter (CS) following exposure to 240kVp X-rays one or more times. Results : A consistent, time-dependent hypersensitive response to a second, or subsequent, dose was observed in the cell lines that demonstrated HRS. This time-dependent change in radiosensitivity did not occur in the radioresistant cell line that did not show HRS (U373). In one cell line that demonstrated strong HRS, T98G, a similar time-dependent hypersensitive response was also seen when the cells were irradiated whilst held in the G1-phase of the cell cycle. In this same cell line, significantly increased cell kill was demonstrated when three very low doses (0.4 Gy) were given per day, 4 h apart, for 5 days, compared with the same total dose given as once-daily 1.2Gy fractions. Conclusions : These data demonstrate the possibility that a multipledose per day, low-dose per fraction regimen, termed 'ultrafractionation', could produce increased tumour cell kill in radioresistant tumours compared with the same total dose given as conventional-sized 2 Gy fractions. 相似文献
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Borderline personality disorder diagnostic criteria, particularly affective dysregulation and behavioral dysregulation, are avenues through which suicide risk is conferred, though pathways are not well understood. The interpersonal theory of suicide may help elucidate these associations. The current study examined indirect relationships between affective and behavioral dysregulation and suicidal ideation through perceived burdensomeness, thwarted belongingness, and the acquired capability for suicide. 169 outpatients completed measures prior to their intake assessment. Perceived burdensomeness accounted for the relationship between affective dysregulation and suicidal ideation. The acquired capability did not explain the association between behavioral dysregulation and suicide attempt history. Affective and behavioral dysregulation may be key targets in treatment for reducing suicide risk. 相似文献