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991.
The aim of this study was to examine the latent structure of the Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition (DSM-IV), Narcissistic Personality Disorder (NPD) criteria in a group of 641 outpatients. The consecutively admitted outpatients were administered the Structured Clinical Interview for DSM-IV Axis II Personality Disorders, Version 2.0, and the Personality Questionnaire. Both confirmatory and exploratory factor analyses (CFA and EFA, respectively) were used to evaluate whether the NPD criteria measure a single latent trait. Latent class analysis was used to assess the diagnostic accuracy of the individual DSM-IV NPD criteria. Mean above minus below a cut (MAMBAC) and maximum covariance (MAXCOV) taxometric analyses were used to evaluate whether the latent distribution of the DSM-IV NPD features is actually discrete. Both CFA and EFA results showed that the 9 DSM-IV NPD criteria loaded on 2 correlated factors. The latent class analysis results suggested a 3-class solution for NPD criteria; relevant differences in diagnostic efficiency were observed among the NPD criteria. MAMBAC and MAXCOV analyses provided consistent evidence of taxonic (ie, discrete) latent structure for NPD. This study gave only partial support to the validity of the DSM-IV NPD construct. Taxometric analyses indicated that a typological model is appropriate for describing NPD, but CFA and EFA suggested the existence of 2 distinct-albeit correlated-clusters of narcissistic features. As a whole, the DSM-IV criteria discriminated NPD from other personality disorders, but diagnostic accuracy statistics did not replicate the rank order of diagnostic efficiency of NPD criteria proposed by the DSM-IV.  相似文献   
992.
OBJECTIVE: To report on clinical features, comorbidity, and response to pharmacotherapy in children and adolescents with obsessive-compulsive disorder (OCD) naturalistically followed and treated with serotonin reuptake inhibitors (SRIs). METHOD: A consecutive series of 94 patients (65 males, 29 females, age 13.6 +/- 2.8 years), referred in the period January 2001-April 2004, diagnosed with a clinical interview (Diagnostic Interview for Children and Adolescents-Revised), and followed for 10 +/- 6 months, were included in the study. RESULTS: Contamination obsessions and washing rituals were associated with less impairment than other subtypes of OCD. Aggressive sexual obsessions and checking rituals as well as symmetry obsessions and ordering-repeating rituals were more frequently comorbid with tic disorders. According to the Clinical Global Impressions-Improvement scale (score 1 or 2), 63 subjects (67%) were responders to treatment. Nonresponders were more severely impaired and had a higher number of comorbid disorders, namely, bipolar disorder and conduct disorder (p < .05). Forty-seven patients (50%) received an SRI monotherapy, whereas the other 47 (50%) needed other medications. Patients receiving SRI monotherapy were less severely impaired; had a later onset of OCD; were at a younger age at the visit, had higher rates of depression and anxiety and lower rates of bipolar disorder, attention-deficit/hyperactivity disorder, and conduct disorder (p < .05). CONCLUSIONS: Long-term naturalistic prospective studies in pediatric patients with OCD might represent an important source of information for everyday care regarding the effectiveness of a treatment over extended periods of time under routine clinical conditions.  相似文献   
993.
Texture discrimination and bounding contour extraction are essential parts of the object segmentation and shape discrimination process. As such, successful texture and contour processing are key components underlying the development of the perception of both objects and surfaces. By recording visual-evoked potentials, we investigate whether young infants can detect orientation-defined textures and contours. We measured responses to an organized texture comprised of many Gabor patches of the same orientation, alternated with images containing the same number of patches, but all of random orientation. These responses were compared with a control condition consisting of the alternation between two independently random configurations. Significant difference potentials were found as early as 2-5 months, as were significant odd harmonics in the test conditions. Responses were also measured to Gabor patches organized either as circles (all patches tangent to an imaginary circular path) alternated with pinwheels (all patches having a fixed orientation offset from the path). Infants between 6 and 13 months also showed sensitivity to the global organization of the elements along contours. Differential responses to our texture and contour stimuli and their controls could only have been generated by mechanisms that are capable of comparing the relative orientation of 2 or more patches, as no local information at a single patch distinguished the random and organized textures or the circle and pinwheel configurations.  相似文献   
994.
995.
996.
Bullous pemphigoid is a rare chronic recurrent dermatosis that is often reported in association with various neurological diseases. No investigation involving a large number of patients has ever been carried out to demonstrate such an association. This study was accomplished by analysing the discharge diagnosis of all hospitalized patients, both day-patients and inpatients, during a 5-year period (1995-2000) covering a total population group of 934,023 living in a region of Italy that has approximately 1,200,000 inhabitants. The results support the hypothesis of an association between bullous pemphigoid, multiple sclerosis and Parkinson's disease on a highly significant statistical basis. The aetiopathogenic mechanisms and the causes that induce the loss of immunological tolerance are not yet understood.  相似文献   
997.
OBJECTIVE: To evaluate the association between different components of smoking history and the clinical severity of psoriasis. DESIGN: A hospital-based cross-sectional study. SETTING: Inpatient wards of a hospital for skin diseases in Rome, Italy. PATIENTS: A total of 818 adults with psoriasis. MAIN OUTCOME MEASURE: The Psoriasis Area and Severity Index was used to assess the clinical severity of psoriasis between February 21, 2000, and February 19, 2002. RESULTS: After adjustment for potential confounders (sex, age, body mass index, psychological distress, family history of psoriasis, duration of psoriasis disease, and alcohol consumption), high intensity of smoking (>20 cigarettes daily) vs a lower level of consumption (< or =10 cigarettes daily) was associated with a more than 2-fold increased risk of clinically more severe psoriasis (odds ratio [OR], 2.2; 95% confidence interval [CI], 1.2-4.1). Cigarette-years, measured as the product of the intensity and duration (years) of smoking, significantly increased the risk of clinically more severe psoriasis after adjustment for confounding factors (OR,1.3; 95% CI, 1.0-1.6, for a 600-U increase in cigarette-years). Separate analyses for men and women showed that the effect of cigarette-years was stronger for women (OR, 1.8; 95% CI, 1.2-2.6, for a 400-U increase in cigarette-years) than for men (OR, 1.2; 95% CI, 0.9-1.6, for a 700-U increase in cigarette-years). CONCLUSION: Smoking is associated with the clinical severity of psoriasis and highlights the importance of smoking cessation in patients with psoriasis.  相似文献   
998.
To investigate efficacy of cystamine induced neuroprotection, we conducted PET imaging studies of cerebral glucose metabolism with [(18)F]FDG (2-deoxy-2-[(18)F]fluoro-d-glucose) and striatal dopamine D2 receptor function with [(11)C]raclopride in R6/2 transgenic Huntington mice. In the control mice, exponentially decreasing glucose utilization was observed in the striatum N(str) [SUV]=(41.75+/-11.80)(58,str)*exp(-(0.041+/-0.007)*t [days]); cortex N(cort) [SUV]=24.14+/-3.66)(58,cort)*exp(-(0.043+/-0.007)*t [days]); and cerebellum N(cer) [SUV]=(34.97+/-10.58)(58,cer)*exp(-(0.037+/-0.008)*t [days]) as a function of age starting at 58 days. Given that the underlying degeneration rate in the cystamine treated mice is similar to that observed in control animals, the protection coefficient (beta) calculated from the equation N(t)=N(58)*exp(-(1-beta)*k*t) was 0.133+/-0.035 for the striatum; 0.122+/-0.028 for the cortex and 0.224+/-00.042 for the cerebellum with a dose of 100 mg/kg. The 50 mg/kg cystamine dose provided significant protection only for the striatum and only minor protection was obtained using lower doses. Striatal binding potential of [(11)C]raclopride was 1.059+/-0.030 in the control mice, and enhanced in the cystamine treated animals in a dose dependent manner up to 1.245+/-0.063 using the 100 mg/kg dose. Histological analysis confirmed cystamine induced neuroprotection of striatal and cortical neurons and Nissl staining revealed that formation of cellular inclusions was reversed in a dose dependent manner. Cerebral imaging and histological evidence support the use of cystamine as a neuroprotective agent for Huntington's disease (HD) pathology.  相似文献   
999.
1000.
Numerous studies on neuro-immuno-modulation indicate that the thymus is involved in many neurological diseases, including experimental allergic encephalomyelitis (EAE). Twenty Lewis rats were induced for EAE. At X, XII, XX and XXX days post-inoculation the animals were killed, and the thymus was recovered and harvested. Specimens of thymus were submitted to morphological light microscopy analysis (1% toluidine blue) and ultra-structural analysis (transmission electron microscopy). Significant morphometric data were collected by examining the images quantitatively and by statistically analysing the values. Our results show that the microenvironment of the thymus is severally involved in acute EAE. Thymocytes and reticular epithelial cells show many changes which are closely related to the pathogenesis of EAE. In particular we observed: (1) inside the cell an increase in intra-cytoplasmic vacuoles, and changes in the thickness of the nuclear membrane, mitochondria, rough endoplasmic reticulum, cellular inter-digitations and cellular electron-density; (2) outside the cell an increase in pericellular translucent halo, intercellular spaces, intercellular contacts and apoptotic and necrotic figures. The evidence of a thymic role in MS may suggest the intriguing therapeutic concept of thymectomy in the management of this neurological disease.  相似文献   
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