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1.
(+/?)3,4‐methylenedioxymethamphetamine (MDMA, “ecstasy”) is an abused psychostimulant that produces strong monoaminergic stimulation and whole‐body hyperthermia. MDMA‐induced thermogenesis involves activation of uncoupling proteins (UCPs), primarily a type specific to skeletal muscle (UCP‐3) and absent from the brain, although other UCP types are expressed in the brain (e.g. thalamus) and might contribute to thermogenesis. Since neuroimaging of brain temperature could provide insights into MDMA action, we measured spatial distributions of systemically administered MDMA‐induced temperature changes and dynamics in rat cortex and subcortex using a novel magnetic resonance method, Biosensor Imaging of Redundant Deviation in Shifts (BIRDS), with an exogenous temperature‐sensitive probe (thulium ion and macrocyclic chelate 1,4,7,10‐tetraazacyclododecane‐1,4,7,10‐tetramethyl‐1,4,7,10‐tetraacetate (DOTMA4?)). The MDMA‐induced temperature rise was greater in the cortex than in the subcortex (1.6 ± 0.4 °C versus 1.3 ± 0.4 °C) and occurred more rapidly (2.0 ± 0.2 °C/h versus 1.5 ± 0.2 °C/h). MDMA‐induced temperature changes and dynamics in the cortex and body were correlated, although the body temperature exceeded the cortex temperature before and after MDMA. Temperature, neuronal activity, and blood flow (CBF) were measured simultaneously in the cortex and subcortex (i.e. thalamus) to investigate possible differences of MDMA‐induced warming across brain regions. MDMA‐induced warming correlated with increases in neuronal activity and blood flow in the cortex, suggesting that the normal neurovascular response to increased neural activity was maintained. In contrast to the cortex, a biphasic relationship was seen in the subcortex (i.e. thalamus), with a decline in CBF as temperature and neural activity rose, transitioning to a rise in CBF for temperature above 37 °C, suggesting that MDMA affected CBF and neurovascular coupling differently in subcortical regions. Considering that MDMA effects on CBF and heat dissipation (as well as potential heat generation) may vary regionally, neuroprotection may require different cooling strategies. Copyright © 2015 John Wiley & Sons, Ltd.  相似文献   
2.
Although traditional diagnostic criteria are accepted for use with mentally retarded persons, diagnosis of psychiatric disorders in this population is often complicated by clinicians' ignoring or underestimating such disorders and by patients' communication problems. The revision of DSM-III and changes in policies of third-party payers have sensitized clinicians to the presence of psychopathology among mentally retarded persons. The authors discuss the relationship between mental illness and mental retardation and review recent research on the diagnosis of specific psychiatric disorders in these patients. Some problems, such as behavioral disruptiveness, psychoses, and phobias, are more prevalent among mentally retarded persons than among other populations, whereas other problems, such as alcoholism and suicide, may be less common.  相似文献   
3.
Edema due to increased capillary permeability (ICP) may be diffuse or localized. Local edemas (Quincke edema, angioneurotic edema) are most often allergic or very rarely due to a defect in C1-inhibitor. Generalized edemas due to ICP share the following clinical features: Fluid retention (subcutaneous edema and diffused swelling) is predominant in lower limbs; it is worsened by orthostatism and warmth and alleviated by decubitus and cold, with important weight variations between morning and evening. It is associated with enhanced thirst, hypotension, oliguria, headaches and blood volume reduction; secondary hyperaldosteronism is the main mechanism. These troubles are due to ICP, associated with lymphatic drainage abnormalities; ICP is measured by the isotopic Landis Test. This abnormality is present in several diseases. Idiopathic orthostatic edema (IOE) is frequent and often unrecognized, occurring mainly in women, often associated with luteal insufficiency. Iatrogenic complications (diuretic and laxative abuses) are frequently superimposed. ICP may be corrected by vitamins P (rutin, anthocyanosides, diosmin, Ginkgo biloba extracts...) Cyclic shock due to ICP is rare. It is characterized by cyclic edema and shock with hypovolemia, hypoproteinemia; the mechanism of shock is a severe loss of fluid and protein from the vascular bed. It is often associated with monoclonal gammapathy and complement activation. In our personal case, the trouble in CP was present all along the disease with permanent edema and low blood pressure (especially in orthostatism). Vit "P" and Ginkgo biloba extracts were able to partially improve CP and the clinical troubles. However, in spite of this treatment a fatal shock occurred after ten years follow-up. Episodic angioedema associated with eosinophilia was first described by Gleich.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
4.
Obsessive-compulsive disorder in mentally retarded patients   总被引:2,自引:0,他引:2  
Of 283 mildly to profoundly retarded patients, 10 (3.5%) presented with compulsive behavior that significantly interfered with their daily functioning. Compulsions occurred in the context of obvious cerebral dysfunction and in the absence of anxiety or "ego-dystonic" qualities. The interrater reliability of the differential diagnosis between compulsions, stereotypies, and other repetitive behaviors was good (kappa = .82). A severity rating scale for the compulsive behavior yielded total scores with good interrater reliability (intraclass correlation coefficient = .82). Single items that described observable behaviors had good reliability, while inner resistance and subjective distress were not reliably assessed and contributed little to the total score. The authors suggest that the DSM-III-R diagnosis of obsessive-compulsive disorder be considered in mentally retarded patients, despite the absence of recognizable ego dystonic characteristics. Emphasis should be on the behavioral, externally observable components of the disorder, rather than on inner conflicts and anxiety. Such a diagnostic approach may also benefit nonretarded compulsive patients.  相似文献   
5.
In order to investigate the role of the idiotypic network in miscarriages, sera from 28 habitually aborting women undergoing paternal leukocyte immunization were studied for the presence of HLA antibodies and related anti-idiotypes. Sixty-eight percent of sera from preimmunized patients which did not contain anti-lymphocyte antibodies inhibited the activity of antibodies to the HLA class I antigens expressed by the spouse. This inhibitory activity could be assigned to IgM antibodies, which cross-inhibit antibodies of similar specificity. This suggests that they are anti-idiotypes for the binding site of HLA antibodies. Immune sera of successfully treated patients exhibited both cytotoxic IgG anti-HLA antibodies and inhibitory IgM anti-idiotypic antibodies. A possible role for an intact idiotypic network in maintaining pregnancy is suggested.  相似文献   
6.
Deficiencies of terminal complement components, particularly the latter ones, are often detected because of increased susceptibility to Neisserial infections. Herein we document the first report of C7 deficiency among a highly inbred Arab population living in the lower Galilee region of Israel. Both biochemical and molecular analysis were performed on samples from infected survivors and parents of children who succumbed to Neisserial infections in a 4-year period. Only the index case who suffered recurrent infections and a sibling who had not suffered an infection during the outbreak were found to be C7-deficient. The mutation was found to be the one previously described to be prevalent among Israeli Jews of Moroccan ancestry (mutation G1135C). The implications of this finding are discussed in the context of family pedigree, the protective effect of complement deficiency, and the clinical outcome.  相似文献   
7.
8.
Belmont MJ  Behar PM  Wax MK 《Head & neck》1999,21(3):264-268
BACKGROUND: Actinomycotic infections of the cervicofacial region are uncommon. Most major medical centers report approximately one case per year. Presenting clinical manifestations are confusing because they often mimic other disease processes. Diagnosis may be difficult due to a general lack of familiarity with the disease and the fastidious nature of the organism in culture. The cervicofacial manifestations of actinomycosis are varied, and a high index of suspicion is required to make an accurate and timely diagnosis. METHODS: Retrospective chart review with the presentation of four unusual cases of actinomycosis were performed. RESULTS: Two patients were initially seen with dysphagia from a tongue base mass. The third patient was initially seen with a 3-week history of worsening hoarseness and stridor. Examination revealed an ulcerative lesion of the left hemilarynx and pyriform sinus. All three patients were thought to have a neoplastic process. Diagnosis was made on histologic examination of a tissue biopsy. The fourth patient was initially seen with a buccal space mass that was draining externally. Culture of the purulent drainage revealed Actinomyces. In all four cases, symptoms resolved after appropriate antimicrobial therapy. CONCLUSIONS: Actinomycosis of the head and neck, although rare, is an important entity to the otolaryngologist. A confusing clinical presentation combined with the fastidious nature of the organism make for a difficult diagnosis. A high index of suspicion is required to make an accurate diagnosis and institute the appropriate antibiotic therapy.  相似文献   
9.
10.
The first EORTC (European Organization of Research and Treatment of Cancer) acute myeloblastic leukemia (AML) pilot study (58872) was conducted between January 1988 and December 1991. Out of 108 patients, 78% achieved complete remission (CR), and event-free survival (EFS) and survival rates (s.e., %) at 7 years were 40 (5) and 51% (6%), respectively. It indicated that mitoxantrone could be substituted for conventional anthracyclines in the treatment of childhood AML without inducing cardiotoxicity. The aim of the next EORTC 58921 trial was to compare the efficacy and toxicity of idarubicin vs mitoxantrone in initial chemotherapy courses, further therapy consisting of allogeneic bone marrow transplantation (alloBMT) in patients with an HLA-compatible sibling donor or chemotherapy in patients without a donor. Out of 177 patients, recruited between October 1992 and December 2002, 81% reached CR. Overall 7-year EFS and survival rates were 49 (4) and 62% (4%), respectively. Out of 145 patients who received the first intensification, 39 had a sibling donor. In patients with or without a donor, the 7-year disease-free survival (DFS) rate was 63 (8) and 57% (5%) and the 7-year survival rate was 78 (7) and 65% (5%), respectively. Patients with favorable, intermediate and unfavorable cytogenetic features had a 5-year EFS rate of 57, 45 and 45% and a 5-year survival rate of 89, 67 and 53%, respectively.  相似文献   
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