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941.
942.
OBJECTIVE: The major aim was to explore the extent to which the Miller Behavioral Style Scale (MBSS) can be used to differentiate cancer patients who are likely to benefit from rehabilitation efforts with a strong information component from those who are not. METHODS: Newly diagnosed patients with breast, gastrointestinal, or prostate cancer (N = 442) were included in a randomized, prospective study of the effects (on anxiety, depression, intrusion, avoidance) of rehabilitation approximately 4 months after diagnosis as compared with control patients. Patients were classified as "monitors" or "blunters" on the basis of the MBSS (368 patients, 83%, completed the MBSS). RESULTS: The expected interaction at postintervention between coping style and experimental condition (ie, rehabilitation or control) was found only for avoidance among breast and prostate cancer patients. Assignment to the rehabilitation or control condition was of no importance for outcome among blunters. Among monitors, the response pattern differed between breast and prostate cancer patients. Prostate cancer monitors seemed to benefit from rehabilitation on all outcome measures, whereas intrusion and avoidance were reduced among breast cancer patients in the control condition. This interaction of diagnosis with condition (rehabilitation or control) among monitors is suggested to be due to demands for diagnosis-specific information during diagnostic work, in the period just after diagnosis, and before treatment decision. CONCLUSIONS: Only the monitor concept seems useful for predicting response to cancer rehabilitation with a strong information component. However, whether rehabilitation is of benefit depends also on other factors.  相似文献   
943.
INK4a/ARF locus codes for two different proteins, p16(INK4a) and p14(ARF), involved in cell cycle regulation. p14(ARF) is considered an upstream regulator of p53 function. To determine the role of these genes in the pathogenesis of human non-Hodgkin's lymphomas we have analyzed exon 1beta, 1alpha, and 2 of the INK4a/ARF locus and p53 gene aberrations in 97 tumors previously characterized for p16(INK4a) alterations. p53 alterations were detected in four of 51 (8%) indolent lymphomas but in 15 of 46 (33%) aggressive tumors. Inactivation of p14(ARF) was always associated with p16(INK4a) alterations. Exon 1beta was concomitantly deleted with exon 1alpha and 2 in eight tumors. One additional lymphoblastic lymphoma showed deletion of exon 1alpha and 2 but retained exon 1beta. No mutations were detected in exon 1alpha and 1beta in any case. Two of the three mutations detected in exon 2 caused a nonsense mutation in the p16(INK4a) reading frame and a missense mutation in the ARF reading frame involving the nucleolar transport domain of the protein. The third mutation was a missense mutation in the p16(INK4a) reading frame, but it was outside the coding region of p14(ARF). Aggressive lymphomas with p14(ARF) inactivation and p53 wild type showed a significantly lower p53 protein expression than tumors with no alteration in any of these genes. In this series of tumors, inactivation of the INK4a/ARF locus mainly occurred in tumors with a wild-type p53 gene because only two lymphomas showed simultaneous aberrations in these genes. Tumors with concomitant alterations of p16(INK4a) and p14(ARF)/p53 genes seem to exhibit a worse clinical behavior than lymphomas with no alterations or isolated inactivation of any of these genes. These findings indicate that p14(ARF) genetic alterations occur in a subset of aggressive NHLs, but they are always associated with p16(INK4a) aberrations. Concomitant disruption of p16(INK4a) and p14(ARF)/p53 regulatory pathways may have a cooperative effect in the progression of these tumors.  相似文献   
944.
Experiencing adverse life events during childhood may increase vulnerability to physical illnesses and psychological disorders during adulthood. We developed an Early Life Events Questionnaire (ELEQ) with 12 scales and administered it to 92 relatively healthy elderly individuals (29 men and 63 women). A canonical-correlation analysis of the 12 ELEQ scales and physical and psychological symptoms revealed a significant canonical correlation. The results indicate that those who grew up in a family with a harsh climate and whose affiliation needs were not met tended to have more psychological and physical symptoms in old age. Regression analysis revealed that, in men, early life events accounted for 42% of the variance in physical symptoms and 39% in psychological symptoms. No significant relationship, however, was found between ELEQ scales and health outcomes in women. These results suggest that women may be less vulnerable than men to the adverse health consequences of childhood deprivation and other misfortunes.This work was supported by Award SA 325 from the Medical Research Service of the Department of Veterans Affairs.  相似文献   
945.
Summary In this report we describe changes in the intracellular redistribution of raf serine/threonine protein kinase (product of the raf proto-oncogene family) in hippocampal neurons following cerebral ischemia in Mongolian gerbils. For immunohistochemical localization studies polyclonal antisera specific for each of the A, B, and Raf-1 isotypes of raf, as well as a pan-raf antisera, were employed. Of these, only sera recognizing B-raf, as well as the general v-raf (raised against the conserved C-terminal region) were positive, indicating that B-raf is the major isotype in this neuronal region. Three different ischemie models were used (repeated 3 times for two min and single 5 or 15 min occlusions, of the common carotid arteries) to demonstrate that ischemie insult causes redistribution of raf protein kinase into the cell nucleus of hippocampal neurons. Increased amounts of raf protein in the nuclei of pyramidal cells following ischemia was confirmed by Western blot analysis of isolated nuclear fractionations. Moreover, an elevation in the level of nuclear raf protein also was detected in the contralateral (i.e. non-occluded hemisphere) neurons of CA1 and CA3 subfields 4 days after the ischemie insult indicating a possible transsynaptic increase in the amount of raf protein along with redistribution. The intranuclear translocation of the immunoreactive material started from the perinucleolar rim and with time extended throughout the nucleus. Enhanced levels and altered redistribution of the raf polypeptide in the nuclei of pyramidal cells of the CA3 subfleld appears to be reversible and returns to the normal level 12 days following the ischemic insult. In addition to triggering the above changes in the intracellular redistribution of raf, ischemie insult also caused an increase in the level of B-raf protein in reactive astrocytes.  相似文献   
946.
To examine the influence of the host cell type on poliovirus RNA synthesis we compared the levels of (-) and (+) strand poliovirus RNA during infection of epithelial (HeLa and HEp-2), leukocytic (U-937, HL-60 and K-562) and nerve (IMR-32) cells. The levels of (-) strand RNA were higher in IMR-32, U-937, K-562 or HL-60 cells than those in HeLa or HEp-2 cells. By contrast, (+) strand RNA content was greater in HeLa or HEp-2 cells. Although significant levels of (+) strand RNA were detected in U-937, K-562 and HL-60 cells, no viral protein synthesis was detected by polyacrylamide gel electrophoretic analysis of metabolically labelled proteins. The molar ratio of poliovirus (-) and (+) RNAs was 2-3 fold higher in IMR-32, U-937 and K-562 cells than in HeLa or HL-60 cells and 5-6 fold higher than in HEp-2 cells. Differentiation of HL-60 cells with a variety of inducers produced differential effects on poliovirus (-) and (+) RNA content and modified the molar ratio of (-)/(+) strand RNAs. These findings indicate that host cell components play a critical role in the regulation of the amount of poliovirus (-) and (+) strand RNAs synthesized during infection.  相似文献   
947.

Introduction

Although an objective structured clinical examination (OSCE) format has been applied in Uruguay since 2004, and providing reliable performance measures, perceptions of it properties and level of student satisfaction have not been determined.

Objective

To evaluate the face validity of OSCE format as a contribution to its local feasibility study.

Material and methods

At the end of the introductory clinical course, the sub-cohort enrolled at the University Hospital responded to a 28-item questionnaire aimed at exploring perceptions about the properties of the OSCE about the potential factors ‘design’ and ‘apparent validity’. After analysing the reliability of the original questionnaire, the questionnaire was refined in an attempt to provide a shorter and more reliable tool.

Results

The original questionnaire showed good internal consistency (Cronbach alpha = 0.70), with a dominance of ‘agreement/total agreement’ opinions on authenticity of the stimuli, dynamic, relevance, and equity of the test. Students perceived organisational obstacles during the test, expressing disagreement to include some stations only aimed at assessing communication skills, and requiring personalised feedback sessions. The refined version of the questionnaire provides consistent measures on student perceptions and is a useful tool that can be widely applied. A discussion is presented on the contributions of this experience to a comprehensive feasibility study of the new format during curriculum transition.

Conclusions

The OSCE is well evaluated by students at the end of the propaedeutic course, supporting its validity. Educational potentials of the new format should be exploited, providing effective feedback to students, clinical teachers, and institutions.  相似文献   
948.
949.
950.
Proportions of T cells and T cell subsets, as identified by their Fc receptors (FcR) for IgM and IgG (Tmu and T gamma), were determined in the peripheral blood lymphocyte (PBL) and cerebrospinal fluid (CSF) lymphocyte populations in patients with multiple sclerosis (MS). On average, MS patients had 79% total T cells (62% of which were T gamma, 66% Tmu) in CSF lymphocytes compared to 66% total T cells (30% T gamma, 63% Tmu) in PBL. Normal age- and sex-matched controls PBL had 74% total T cells (20% T gamma, 54% Tmu). By direct observation using an indirect immunofluorescence assay, 41% of the CSF T gamma cells in MS patients bore receptors for IgM; these cells were designated T gamma mu and, according to the double-marker analysis, did not seem to correlate with disease stage. In MS PBL, 20% of T gamma cells were T gamma mu compared to 9% in the control PBL T gamma population. Thus, MS patients had a higher proportion of total T cells, T gamma cells and T gamma mu cells in their CSF than in their peripheral blood and than those populations found in normal control blood. The significance of this T gamma mu population for the continuing disease state in MS is discussed.  相似文献   
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