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1.
We propose a novel fully automated method for retrospective correction of intensity inhomogeneity, which is an undesired phenomenon in many automatic image analysis tasks, especially if quantitative analysis is the final goal. Besides most commonly used intensity features, additional spatial image features are incorporated to improve inhomogeneity correction and to make it more dynamic, so that local intensity variations can be corrected more efficiently. The proposed method is a four-step iterative procedure in which a non-parametric inhomogeneity correction is conducted. First, the probability distribution of image intensities and corresponding second derivatives is obtained. Second, intensity correction forces, condensing the probability distribution along the intensity feature, are computed for each voxel. Third, the inhomogeneity correction field is estimated by regularization of all voxel forces, and fourth, the corresponding partial inhomogeneity correction is performed. The degree of inhomogeneity correction dynamics is determined by the size of regularization kernel. The method was qualitatively and quantitatively evaluated on simulated and real MR brain images. The obtained results show that the proposed method does not corrupt inhomogeneity-free images and successfully corrects intensity inhomogeneity artefacts even if these are more dynamic.  相似文献   
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Background:  Data concerning the effects of alcohol on social interaction in everyday life are limited.
Methods:  Healthy volunteers in 4 studies of social behaviors and mood were instructed to complete record forms immediately after a social interaction had occurred, a method known as event-contingent recording. Record forms asked questions about quarrelsome, agreeable, dominant, and submissive behaviors; about aspects of mood; and, in 3 studies, about perceptions of others. Each form also contained a question about alcohol consumption prior to a social interaction. For the present report, only social interactions taking place in the evening and outside the work setting were included. Only individuals who consumed alcohol at least once in these circumstances were included ( n  = 171).
Results:  Social interactions involving alcohol were primarily characterized by higher levels of agreeable behaviors, by perceptions of greater agreeableness in others, and by more positive mood. Alcohol consumption was not associated with higher levels of quarrelsomeness.
Conclusions:  Alcohol consumption in a social context may have predominantly positive effects, an observation which is at odds with most alcohol-induced aggression experiments performed in laboratory settings. Drinking in everyday life may be less likely to result in aggression because, unlike in most laboratory experiments, individuals can choose among a variety of behaviors in response to social cues and the alcohol dose consumed is usually lower. Event-contingent recording provides a new approach for the study of alcohol's effects in everyday life and the conditions in which alcohol might result in interpersonal aggression.  相似文献   
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Background:

Individuals with a family history of depression show subtle abnormalities in the processing of social stimuli. This could negatively affect their interpersonal functioning and contribute to their depression risk. Repeated administration of the serotonin precursor tryptophan has previously been shown to increase agreeable behavior and reduce quarrelsome behavior in irritable people, who are also considered at risk for depression.

Methods:

To examine the effects of tryptophan on social functioning in individuals with a family history of depression, 40 men and women with at least one first-degree relative with depression received tryptophan (1g three times a day) and placebo for 14 days each in a double-blind crossover design and recorded their social behavior and mood during everyday interpersonal encounters. Participants also provided daily ratings of their positive and negative cognitions concerning their social functioning.

Results:

Tryptophan improved mood. Unexpectedly, tryptophan increased quarrelsome behavior and reduced agreeable behavior, specifically during interactions at home. The behavioral effects of tryptophan were not moderated by mood or by the interaction partner. Negative social cognitions were lower when tryptophan was given second and lower during placebo when placebo was given second.

Conclusion:

Overall, tryptophan may not alter social behavior in individuals with a family history of depression as it does in irritable people. However, the behavioral effects of tryptophan at home might be seen as a way for individuals with a family history of depression to achieve more control. Over time, this may positively influence the way they feel and think about themselves in a social context.  相似文献   
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A patient with longstanding ankylosing spondylitis (AS) developed a cauda equina syndrome. The myelogram showed a block at the L2 level. Vertebral computerised tomography showed calcification in the centre of the spinal canal. The patient also had features suggestive of a diffuse idiopathic skeletal hyperostosis (DISH). Meningeal calcification has never been reported in AS, so we suggest that this is related to an associated DISH. Cauda equina syndrome has not been described in DISH, and calcification of meninges has not been reported in AS, so we suggest that the meningeal calcifications and associated cauda equina syndrome are related to DISH.  相似文献   
6.
OBJECTIVE: To determine the range and activity of the clinical and biological features of patients aged <40 with Paget's disease of bone. METHODS: A retrospective two centre study of 314 patients with Paget's disease of bone from two university hospitals. The disease was diagnosed by radiological, serum alkaline phosphatase (AP) levels, or clinical features, and bone scintigraphy in most patients. Demographic data, reason for diagnosis, bones affected, disease extent using Coutris' index, complications during progression, and disease activity using Renier's index were assessed. Patients over and under 40 were compared. RESULTS: 18/314 (5.7%) patients were diagnosed before the age of 40; median (SD) age was 35.4 (5.5) (range 18-40) and AP 555.6 (566.3) IU/l (range 70-1949). Coutris' extension index was 12.8 (10.5) and Renier's activity index 35.9 (31.9). Younger patients had more affected bones (p<0.05) than those aged >40, higher level of extension (p<0.05), higher AP value (p = 0.05), and greater incidence of thoracolumbar spine disease. Disease activity did not differ significantly between the groups. CONCLUSIONS: Paget's disease diagnosed before the age of 40 is more extensive but not more active, with higher AP values than in those diagnosed after age 40.  相似文献   
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Hypercortisolism due to an ACTH-secreting pituitary adenoma (Cushing’s disease) is a chronic condition associated with high morbidity and mortality if inadequately managed. Pasireotide is a multireceptor-targeted somatostatin analogue and is the only approved medical therapy for Cushing’s disease that treats the underlying cause of the disorder. This paper reviews the available literature for medical-therapy-induced adenoma volume reduction in patients with Cushing’s disease and reports the experience of a 53-year-old surgically, radiologically and medically naïve (de novo) female with a pituitary macroadenoma who declined surgery. This patient was treated with pasireotide as first-line therapy as part of the largest randomized Phase III study evaluating a medical therapy in patients with Cushing’s disease (SOM230B2305 trial). Subcutaneous pasireotide significantly decreased tumor volume, suppressed cortisol secretion, and improved clinical signs and symptoms of Cushing’s disease in this patient. Based on this experience, first-line pasireotide has the potential to achieve substantial tumor volume reduction in addition to significant improvements in cortisol levels and signs and symptoms in patients with Cushing’s disease for whom surgery is not an option.  相似文献   
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ObjectiveSystemic lupus erythematosus (SLE) is an autoimmune disease which may has joint impairment. Often, SLE patients complain of hand and wrist arthralgia (HA). Usually, these patients do not show any swelling in the physical exam. Our aim was to demonstrate Power Doppler Ultrasound (PDUS) abnormalities in SLE patients with HA.MethodsWe recruited 58 consecutive SLE patients and divided them into two groups: case group (n = 28) were patients with HA, and control group (n = 30) were patients without HA. We also collected socio-demographic and disease activity data, biological markers and SLEDAI index. We evaluated disability and quality of life by mHAQ and SF-12, respectively. We performed a bilateral hand and wrist PDUS on all patients. PDUS findings were based in OMERACT-7 group criteria.ResultsWe found PDUS abnormalities in most of SLE patients who suffered HA, when compared to SLE controls (P < 0.001). The main findings in Case Group were: tenosynovitis (39.2%), synovial effusion or hypertrophy (25%) and active synovitis (14.2%). SLEDAI score and dsDNA antibodies were related to the presence of PDUS abnormalities (P < 0.05 and P < 0.001, respectively). We also found worse physical SF-12 (P < 0.05) and mHAQ (NS) scores in case group.ConclusionsSLE patients who present HA have more PDUS abnormalities. These findings are associated with a higher SLEDAI score and dsDNA antibodies. This articular affection may contribute to a worsened functional ability and a lower quality of life. PDUS seems to be a reliable tool in the assessment of SLE patients with HA.  相似文献   
10.
The high sequence identity observed between UNC-93B of mouse and human imply common evolutionary ancestors and a conserved function. A nonconservative point mutation in the mouse Unc93b1 gene has been associated with defective Toll-like receptor (TLR) signaling and impaired major histocompatibility complex (MHC) I and II restricted antigen responses. Like murine UNC-93B, the human homologue is predicted to form 12 transmembrane domains, and it localizes to the endoplasmic reticulum. In human beings its expression is highest in professional antigen-presenting cells such as dendritic cells and macrophages. Interestingly, UNC-93B itself is specifically induced by TLR3 signaling in monocyte-derived dendritic cells and macrophages. To study the effect of UNC-93B deficiency in TLR signaling and antigen-presentation in human beings, UNC-93B message was knocked down in monocyte-derived dendritic cells and a reduced TNFalpha production in response to TLR3 agonists was observed. In the same experiment, the achieved knockdown had no effect on an MHC II-dependent antigen response, suggesting that the reduced quantity of human UNC-93B was still capable of supporting class II antigen presentation or that UNC-93B is not required for class II antigen presentation in human antigen-presenting cells.  相似文献   
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