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BACKGROUND: Limited knowledge exists regarding the neurobiology of trichotillomania (TTM). Cerebellum (CBM) volumes were explored, given its role in complex, coordinated motor sequences. METHODS: Morphometric magnetic resonance imaging (MRI) scans were obtained for 14 female subjects with DSM-IV diagnoses of TTM and 12 age-, education-, and gender-matched normal control (NC) participants. Parcellation was performed utilizing a recently developed methodology to measure subterritory volumes of the CBM. Regions were defined based on knowledge of the structural and functional subunits of the CBM. RESULTS: As predicted, significant group differences were reported for CBM raw cortical volumes (p = .008) that survived correction for total brain volume (TBV; p = .037) and head circumference (HC; p = .011). A priori and post hoc group raw volume comparisons for CBM subterritories and functional clusters revealed many significant differences. However, most differences failed to withstand correction for total CBM volumes (TCV). Smaller volumes were consistently reported for the TTM versus NC cohorts. Total Massachusetts General Hospital Hair Pulling Scale (MGHHPS) scores were significantly inversely correlated with left primary sensorimotor cluster volumes (p = .008), with smaller volumes associated with more severe TTM symptoms. CONCLUSIONS: These findings implicate the CBM in the neurobiology of TTM, with reduced subterritory volumes reported for the TTM versus NC groups.  相似文献   
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Effects of age on volumes of cortex, white matter and subcortical structures   总被引:11,自引:0,他引:11  
The effect of age was investigated in and compared across 16 automatically segmented brain measures: cortical gray matter, cerebral white matter, hippocampus, amygdala, thalamus, the accumbens area, caudate, putamen, pallidum, brainstem, cerebellar cortex, cerebellar white matter, the lateral ventricle, the inferior lateral ventricle, and the 3rd and 4th ventricle. Significant age effects were found for all volumes except pallidum and the 4th ventricle. Heterogeneous age responses were seen in that age relationships for cortex, amygdala, thalamus, the accumbens area, and caudate were linear, while cerebral white matter, hippocampus, brainstem, cerebellar white, and gray matter, as well as volume of the lateral, inferior lateral, and 3rd ventricles showed curvilinear relationships with age. In general, the findings point to global and large effects of age across brain volumes.  相似文献   
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OBJECT: The goal of this study was to test hypotheses regarding changes in volume in subcortical structures following anterior cingulotomy. METHODS: Morphometric magnetic resonance (MR) imaging methods were used to assess volume reductions in subcortical regions following anterior cingulate lesioning in nine patients. Magnetic resonance imaging data obtained before and 9 +/- 6 months following anterior cingulotomy were subjected to segmentation and subcortical parcellation. Significant volume reductions were predicted and found bilaterally within the caudate nucleus, but not in the amygdala, thalamus, lenticular nuclei, or hippocampus. Subcortical parcellation revealed that the volume reduction in the caudate nucleus was principally referrable to the body, rather than the head. Furthermore, the magnitude of volume reduction in the caudate body was significantly correlated with total lesion volume. CONCLUSIONS: Taken together, these findings implicate significant connectivity between a region of anterior cingulate cortex (ACC) lesioned during cingulotomy and the caudate body. This unique data set complements published findings in nonhuman primates, and advances our knowledge regarding patterns of cortical-subcortical connectivity involving the ACC in humans. Moreover, these findings indicate changes distant from the site of anterior cingulotomy lesions that may play a role in the clinical response to this neurosurgical procedure.  相似文献   
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Background Food allergy (FA) represents a common and worldwide disorder but in publications referring to FA the reported diagnosis is rarely confirmed. Consequently, the subjectively assessed FA may negatively affect the quality of life of patients and their families. Objective We have conducted this internet survey in order to estimate the self‐reported perception of FA in Greece. Methods A standard anonymous questionnaire was posted for a 3‐month period on http://www.in.gr , a Greek popular Internet portal. Each individual could participate only once. Participants were screened for the presence or history of FA by a key question and were then asked to provide information on symptoms, course and management. Results A total of 3673 adult subjects (mean age 34.2 years, range 18–74, females 61.3%), reporting FA were included in analysis. Most reported reactions were related to fruits (14.9%), seafood (10.7%) and nuts (9.2%). The first episode occurred principally during the second (29.2%) and third (30.9%) decade within 3 h from consumption (82.2%). Predominant symptoms were urticaria and oral allergy syndrome (almost 25% each one). Nearly half of the participants sought no medical advice, while 31.4% asked for an allergist’s consultation. Almost 21% of reactors were hospitalized; nuts, severity of symptoms (lower respiratory and/or cardiovascular), onset in lower age, previous exercise and concomitant alcohol and/or aspirin intake were positively associated with hospitalization. Conclusion Although FA causes severe anaphylactic episodes, almost 50% of individuals who experience symptoms perceived as FA do not seek medical advice. Awareness programmes must be carried out in order to increase consciousness about this potentially fatal medical condition.  相似文献   
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Beekeepers are at increased risk for honeybee (Hb) venom allergy and they represent a unique population for Hymenoptera venom studies. The aim of this was to prospectively examine the pattern of Hb venom sensitization over a 5-year period in new beekeepers and define possible predisposing factors. Thirty-five beekeepers were tested every 6 months for 5 years with in vivo and in vitro methods to detect the possible development of sensitization to Hb and common wasp (Cw) venom. Inclusion criteria included the lack of previous beekeeping activity and absence of sensitization or reported reaction to Hymenoptera stings. Subjects with both in vivo and in vitro tests that were definitely positive or with one definitely positive and the other doubtful were considered sensitized. Ten of 35 new beekeepers (28.6%) and 3 of 36 controls (8.3%) developed sensitivity to Hb venom during the 5-year period. The risk ratio in incidence studies was calculated at 3.43 (SE of log risk ratio = 0.61; 95% CI of risk ratio = 1.03-11.42). All sensitized beekeepers were detected within the first 18 months of occupational exposure; 8 of 10 (80%) beekeepers were detected during the initial 12 months and the 2 remaining beekeepers were detected between 12 and 18 months. One of 35 (2.9%) beekeepers and 1 of 36 controls (2.8%) were sensitized to Cw venom. The number of stings per year and atopy had no effect on sensitization rate. Although predisposing factors to sensitization or anaphylaxis could not be identified, beekeepers developed sensitization to bee venom in <18 months.  相似文献   
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The natural history of chronic hepatitis C in haemophiliacs   总被引:6,自引:0,他引:6  
Most haemophiliacs treated with non-virally-inactivated clotting factor concentrates have been infected with hepatitis C virus (HCV). We have studied the natural history of chronic HCV infection by following all 138 HCV-positive patients from our centre for periods of up to 28 years. As well as the clinical and biochemical characteristics, we studied 116 liver samples from 63 patients obtained at elective biopsy ( n =103) or autopsy ( n =13). 36 (26%) of the patients were HIV positive, and three were chronic carriers of hepatitis B. Evidence of previous exposure to hepatitis A and B was found in 37.2% and 48.1% respectively. Raised transaminase levels were found in 82.6% of patients. 11 of 15 patients with normal transaminases tested by PCR for HCV RNA were positive, indicating that most patients, even in this group, have chronic hepatitis C infection. Cirrhosis was diagnosed by liver histology in 19 patients, and nine patients developed liver failure. The incidence of cirrhosis rose rapidly 15 years after HCV infection to 15.6 per 1000 person-years. Multivariate analysis showed that HIV status, length of time since HCV infection and age at HCV infection were independently associated with both the development of cirrhosis and liver failure. Two patients developed hepatocellular carcinoma; one of these was exposed only to a single batch of FVIII concentrate 11 years earlier. Chronic hepatitis C is increasingly recognized as a major cause for morbidity and mortality in haemophiliacs, especially those who are HIV positive and who were infected at an older age.  相似文献   
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CardioVascular and Interventional Radiology - The interventional radiology (IR) trainee recruitment in the UK is lagging behind the pace of service expansion and is potentially hindered by...  相似文献   
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