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71.
OBJECTIVE: The goal of this study was to determine whether self-mutilators with personality disorders differ from nonmutilators with personality disorders in impulsivity, aggression, and other psychopathology and whether serotonergic dysfunction contributes to self-mutilation. METHOD: Twenty-six self-mutilators with personality disorders were matched to 26 control subjects with personality disorders for gender, age, education, axis I diagnosis of affective disorder, and axis II diagnosis of personality disorder. Numerous indexes of psychopathology as well as CSF 5-hydroxyindoleacetic acid (5-HIAA) levels and platelet imipramine binding sites (Bmax) and affinity (Kd) were determined. RESULTS: Self-mutilators had significantly more severe character pathology, had greater lifetime aggression, and were more antisocial than the control subjects. The self-mutilators scored higher on the Hamilton Rating Scale for Depression but not on the Beck Depression Inventory or the Beck Hopelessness Scale. The two groups did not differ on the Buss-Durkee Hostility and Guilt Inventory or on the Sensation Seeking Scale. The degree of self-mutilation was significantly correlated with impulsivity, chronic anger, and somatic anxiety. Both self-mutilation and impulsivity showed significant negative correlations with Bmax, although the two groups did not differ in CSF 5-HIAA levels or in platelet imipramine binding. CONCLUSIONS: The results demonstrate the contribution of severe character pathology, aggression, impulsivity, anxiety, and anger to self-mutilation and provide preliminary support for the hypothesis of underlying serotonergic dysfunction facilitating self-mutilation.  相似文献   
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Variations in levels of motivation to learn among established general practitioners (GPs) have received scant attention. Building on previous work, we present an analysis of factors contributing to the development of motivation to learn in those who are entering and already established in practice. This approach suggests that individual motivation is both complex and unstable in response to external factors. We draw attention to the possibility of motivational immaturity in recruits to general practice, the contribution of values, and the presence of demotivators. The implications of our analysis are explored in relation to individual professional development and continuing education provision. We suggest that motivational audit will identify individual and contextual factors that are reducing the capacity of GPs to continue learning. A number of approaches addressing these factors are proposed.  相似文献   
75.
K B Seydel  T Zhang    S L Stanley  Jr 《Infection and immunity》1997,65(9):3951-3953
Animal models of liver abscess formation with Entamoeba histolytica suggest that the neutrophil is the first cell of the host immune system to interact with the invading ameba. In vitro studies have suggested that lysis of neutrophils by virulent amebae may exacerbate the damage seen in amebic liver abscesses. To investigate the role of neutrophils in vivo, we used the severe combined immunodeficient (SCID) mouse model of amebic liver abscess formation and compared liver damage in neutrophil-depleted and control mice. We found that neutrophil-depleted animals have significantly larger amebic liver abscesses at early stages of infection and that abscesses in neutrophil-depleted SCID mice lack the prominent inflammatory cell ring seen in amebic liver abscesses in control SCID mice. These data suggest that neutrophils play a protective role in the early host response to amebic infection of the liver.  相似文献   
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Forty-one cases of chondrosarcoma from varying sites throughout the body, and treated exclusively by one of the authors (R. L. H.) from 1972 to 1990 were reviewed. The symptoms, signs, location of tumours, treatment and progress are presented. Particular attention was paid to modular bone replacement techniques. Excision and reconstruction of the bone or joint were carried out in 17 femora, five tibia and six humeri. Comparison between this method of management and other techniques is discussed. Titanium and alumina prostheses for the hip, femur, tibia, shoulder and humerus have been designed by the senior author. These are both inert and modular, and have been found to be superior to other methods of treatment in both function and cosmesis. They do not possess the same potential donor infection risks and other disadvantages of allograft replacement. Immediate postoperative weight bearing and mobilization are possible with these systems. The Huckstep prostheses allow for bony in growth into their porous coated alumina sleeves, spacers and stems. In addition, the titanium alloy locking component for the femoral stems has an elasticity half that of other metal alloys and this was found to minimize stress shielding.  相似文献   
77.
The cholinergic hypothesis of memory dysfunction has guided most of the recent proposals for treating the primary symptoms of AD. The efficacy of these treatments has been severely limited. This review examines two major lines of evidence which suggest that the cholinergic hypothesis may have to be expanded and revised. The cholinergic hypothesis focuses on pre-synaptic defects. It assumes cholinoceptive neurons would function normally with adequate stimulation. Evidence is not sufficient to support this assumption. In addition, dissociations have been demonstrated between muscarinic receptor number and functional response of cholinoceptive neurons. Various measures are proposed to investigate the functional integrity of muscarinic receptors in AD patients. AD often has been characterized as a disorder produced by generalized cholinergic hypoactivity. Evidence for cortisol hypersecretion, abnormal dexamethasone suppression, and the occurrence of depressive symptoms, motoric dysfunction and sleep abnormalities in AD patients is more consistent with regional cholinergic hyperactivity than generalized hypoactivity. Resolution of these discrepancies could shed new light on the pathophysiology and treatment strategies for AD. Cholinoceptive neurons could be hypersensitive, subsensitive or have unaltered responsivity. These options would have very different treatment implications. New developments in outcome assessment which are capable of discriminating varieties of differential response to treatment can spur treatment development and improve quality of care for patients with complex disorders such as AD.  相似文献   
78.
Cells transformed by the McDonough strain of feline sarcoma virus (SM-FeSV) express a v-fms-encoded glycoprotein whose expression at the cell surface correlates with the transformed phenotype. The mouse mononuclear phagocyte growth factor CSF-1 specifically binds to SM-FeSV-transformed cells at high-affinity sites indistinguishable from those detected on normal feline macrophages. A monoclonal antibody to a v-fms-encoded epitope competed for CSF-1 binding to SM-FeSV-transformed cells, and chemical crosslinking demonstrated that murine CSF-1 bound to the v-fms gene product at the cell surface. Although SM-FeSV-transformed fibroblast lines were found to secrete CSF-1, the growth of transformed cells was not affected by antibodies to the v-fms gene product or to the growth factor. Tyrosine phosphorylation of the v-fms products in membranes was observed in the absence of CSF-1 and was not enhanced by addition of the murine growth factor. The data support the hypothesis that the c-fms protooncogene product is related, and possibly identical, to the CSF-1 receptor and suggest that the v-fms-encoded kinase functions in the absence of an exogenous growth factor.  相似文献   
79.
Academic Achievement of Children with Epilepsy   总被引:31,自引:23,他引:8  
The academic achievement scores of 122 children with epilepsy were examined in relation to demographic and clinical seizure variables. As a group, these children were making less academic progress than expected for their age and IQ level. Academic deficiencies were greatest in arithmetic, followed by spelling, reading, comprehension, and word recognition. Results of the multiple regression analyses indicated a modest combined predictive significance of the demographic and clinical seizure variables for academic performance. In addition, the magnitude of these relationships varied by academic area. Among the individual variables examined the strongest correlates of academic performance were age of the child, age of seizure onset, lifetime total seizure frequency, and presence of multiple seizures (absence and tonic-clonic). These results are discussed in relation to developing an understanding of the factors which underlie academic vulnerability in children with epilepsy.  相似文献   
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