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101.
All first-time admissions from 1970 to 1986 with obsessive-compulsive neurosis (OCD) (ICD-8 diagnosis number 300.39) or obsessive-compulsive personality disorder (OCPD) (ICD-8 diagnosis number 301.49) were analyzed based on an extract from the nationwide Psychiatric Case Register in Denmark. All patients with secondary diagnoses other than neurotic disorders or personality disorders (including “neuroses characterogenes”) were excluded from the study. A total of 284 patients were first-time admitted with a main diagnosis of OCD during the period. The sex ratio was 0.67 (males/females). A total of 126 were first-time admitted with a diagnosis of OCPD, with a sex ratio of 1.18 (males/females). Seventy-seven percent of the readmitted patients with a first-time diagnosis of OCD kept a diagnosis within the “emotional spectrum” at the last admission. About half kept OCD as a main diagnosis, whereas only 15% shifted to a severe psychiatric diagnosis such as schizophrenia or manic-depressive psychosis. Of the readmitted patients with OCPD. 13% later developed a diagnosis of manic-depressive psychosis.  相似文献   
102.
Summary MRI-autopsy correlation in a case of gliomatosis cerebri suggests that poor gray-white matter demarcation on MRI may be sign of neoplastic infiltration. The extent of infiltration is imperfectly assessed by current imaging modalities.  相似文献   
103.
BALB/c mice were bilaterally implanted with bipolar electrodes either in anterodorsal (ADH) or posteroventral hippocampus (PVH) in order to compare the effects of postsession electrical stimulation on memory processes. For each experiment, 30 s after the end of the first session, the animals were stimulated during 80 s. For both hippocampal regions, the stimulation intensity was half of the afterdischarge threshold value. Control groups were naive, ADH and PVH implanted non-stimulated animals. Different appetitive and aversive tasks were used. Subseizure stimulation never created a deficit. Depending on the region of the hippocampus stimulated and on the learning task, a retention enhancement was eventually observed. These data are in agreement with the involvement of hippocampus in initial stages of memory consolidation. Further, the subseizure stimulation permitted a functional dissociation between the two hippocampal regions. Both regions seemed involved in the integration of information, but the anterodorsal part would be rather related to behavioral inhibition, while the posteroventral part would have the capacity to induce an arousal state allowing behavioral flexibility.  相似文献   
104.
All cases of acute intermittent porphyria (AIP) are believed to be caused by a mutation in the gene encoding for porphobilinogen deaminase, a rate-limiting enzyme in the haem synthetic pathway. This gene has been mapped to the long arm of chromosome 11, a region of the genome that has recently attracted considerable attention as a possible location for genes implicated in major mental disorder. This study was designed to show whether major mental illness co-segregated with acute intermittent porphyria in families where the two conditions are found. The study also investigated the relation between clinical mental symptoms and biochemical parameters of acute intermittent porphyria. The case records of 344 consecutive patients admitted to the Porphyrias Research Group in the Western Infirmary in Glasgow between 1950 and 1988 with acute intermittent porphyria were examined for evidence of psychiatric contact. Of 16 individuals identified, 12 were available for the study. Forty relatives of these 12 probands, including 9 who were asymptomatic carriers of AIP, were interviewed for lifetime history of mental illness and current symptoms. Comparisons were made between 4 groups of patients based on urinary porphyrin levels and erythrocyte enzyme activity; 1) manifest acute intermittent porphyria, 2) latent acute intermittent porphyria, 3) normal relatives and 4) total acute intermittent porphyria (latent and manifest combined). No association was found between AIP and schizophrenia or manic-depressive illness. Only one patient with schizophrenia was found in the sample of 344 case notes, and in 2 families bipolar illness was found but did not segregate with acute intermittent porphyria. The commonest psychiatric diagnosis in patients was generalized anxiety. In the total AIP group (latent and manifest), compared with normals, the rating scale measures of anxiety were significantly correlated with the level of porphyrin metabolites in the urine at the time of rating. This was true even in subjects with latent AIP, who were not at the time of testing aware that they were asymptomatic carriers of the illness. AIP should be considered in the differential diagnosis of generalized anxiety disorder.  相似文献   
105.
Auditory oddball scalp and limbic P3s were recorded from 18 patients with unilateral temporal lobe epilepsy (TLE) prior to seizure surgery. Limbic P3s were unilaterally absent ipsilateral to the seizure focus and were present in the nonepileptogenic temporal lobe in all 18 cases studied. Scalp P3s, recorded from C3 and C4, on the other hand, were elicited bilaterally and there was no significant difference in amplitude or latency between the epileptogenic and nonepileptogenic sides. These data concur with studies of scalp P3 performed following surgery and suggest that the assessment of the contribution of limbic P3 to scalp P3 may be masked by volume conduction effects and other generators of P3. We conclude that the P3 recorded from central scalp sites, unlike its limbic counterpart, offers little clinical information in the presurgical assessment of patients with TLE.  相似文献   
106.
A mesenteric cyst with milk of calcium in an adult patient is presented. Preoperative evaluation included plain film, ultrasound, computed tomography (CT), and magnetic resonance imaging (MRI). To our knowledge, the presence of milk of calcium in a mesenteric cyst has not been previously described.  相似文献   
107.
The purpose of this study was to characterize the contrast caused by a susceptibility MRI contrast agents, on spin echo T2-weighted imaging of reperfused myocardial infarction. Our interest in this model focused on the expected requirement that such agents be compartmentalized in the tissue to cause signal loss on spin echo images, a condition which may not be present in reperfused infarcted myocardium. Accordingly, nine rats were subjected to 2 h of left coronary artery occlusion followed by 3 ± 0.5 h of reperfusion prior to administration of contrast media. Three sets of MR images were acquired: (a) baseline axial images at the midventricle, both T1-weighted (TR/TE = 300/20) and T2-weighted (TR/TE = 1500/60); (b) T1-weighted images after administering a T1-enhancing agent, Gd-DTPA-BMA (0.2 mmol/kg), to document that contrast media is delivered to the reperfused infarction; and (c) T2-weighted images after administering the susceptibility agent, Dy-DTPA-BMA (1.0 mmol/kg). Gadolinium-enhanced T1 images depicted reperfused infarction as regions with greatly enhanced signal intensity compared with unin-farcted myocardium, indicating that contrast agent was delivered to the infarcted zone. Dysprosium-enhanced T1 images depicted the injury as a region of persistent signal intensity relative to depletion of signal in normal myocardium, consistent with failure of the contrast agent to cause signal loss. Similar infarction sizes were observed for unenhanced T2-weighted images (33 ± 5%), gadolinium-enhanced T1 weighted images (36 ± 5%) and postmortem staining (30 ± 6%); strong correlations (r > 0.9) were noted in comparisons of these data. Dysprosium-enhanced images exhibited a smaller region of differential signal presumed to be infarction (20 ± 5%, P < 0.05) and weak correlations (r < 0.75) with the other measurements. We conclude that the smaller infarction depicted on dysprosium-enhanced images is a subregion of the true infarction in which myocardial necrosis is sufficiently advanced that the agent is homogeneously distributed throughout all tissue compartments, preventing T2*-dependent phase loss on spin echo images.  相似文献   
108.
We assessed the effect of a broad spectrum glutamatergic receptor antagonist, kynurenic acid (500 mg/kg) on ischemia-induced hippocampal glutamate release and neuronal damage. Kynurenic acid significantly decreased glutamate release during ischemia but had no effect on the hippocampal lesion. Some protection was observed in the cortex and in the striatum. These data suggested that the extracellular accumulation of glutamate during forebrain ischemia does not play a major role in the hippocampus.  相似文献   
109.
A number of pulse sequence techniques, including magnetization-prepared gradient echo (MP-GRE), segmented GRE, and hybrid RARE, employ a relatively large number of variable pulse sequence parameters and acquire the image data during a transient signal evolution. These sequences have recently been proposed and/or used for clinical applications in the brain, spine, liver, and coronary arteries. Thus, the need for a method of deriving optimal pulse sequence parameter values for this class of sequences now exists. Due to the complexity of these sequences, conventional optimization approaches, such as applying differential calculus to signal difference equations, are inadequate. We have developed a general framework for adapting the simulated annealing algorithm to pulse sequence parameter value optimization, and applied this framework to the specific case of optimizing the white matter-gray matter signal difference for a T1-weighted variable flip angle 3D MP-RAGE sequence. Using our algorithm, the values of 35 sequence parameters, including the magnetization-preparation RF pulse flip angle and delay time, 32 flip angles in the variable flip angle gradient-echo acquisition sequence, and the magnetization recovery time, were derived. Optimized 3D MP-RAGE achieved up to a 130% increase in white matter-gray matter signal difference compared with optimized 3D RF-spoiled FLASH with the same total acquisition time. The simulated annealing approach was effective at deriving optimal parameter values for a specific 3D MP-RAGE imaging objective, and may be useful for other imaging objectives and sequences in this general class.  相似文献   
110.
目的 :进一步探讨 MRI增强前后的准备与护理方法。材料与方法 :共增强 833例 ,男 5 85例 ,女 2 4 8例。使用顺磁性造影剂 Gd- DTPA,按 0 .2 m L/kg体重给药。其中双倍量增强 110例 ,增强前认真履行告知义务和签署同意书。发生造影剂外漏者给予鲜马铃薯片外敷。结果 :增强效果达良好以上共 82 5例 ,占 99% ,未发生严重负反应。 3例造影剂外漏 ,鲜马铃薯片外敷后 3h痊愈。结论 :增强前充分细致的准备是保证增强效果的重要因素。认真履行告知义务和签置同意书 ,不仅尊重了病人的权利 ,也是依法行医 ,保证医疗安全的需要  相似文献   
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