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排序方式: 共有722条查询结果,搜索用时 15 毫秒
1.
F Sebastiano G Di Gennaro V Esposito A Picardi R Morace A Sparano A Mascia C Colonnese G Cantore P P Quarato 《Clinical neurophysiology》2006,117(2):341-347
OBJECTIVES: To evaluate a novel method for localization of subdural electrodes in presurgical assessment of patients with drug-resistant focal epilepsy. METHODS: We studied eight consecutive patients with posterior epilepsy in whom subdural electrodes were implanted for presurgical evaluation. Electrodes were detected on post-implantation brain CT scans through a semiautomated procedure based on a MATLAB routine. Then, post-implantation CT scans were fused with pre-implantation MRI to localize the electrodes in relation to the underlying cortical structures. The reliability of this procedure was tested by comparing 3D-rendered MR images of the electrodes with electrode position as determined by intraoperative digital photography. RESULTS: In each patient, all electrodes could be correctly localized and visualized in a stereotactic space, thus allowing optimal surgery planning. The agreement between the procedure-generated images and the digital photographs was good according to two independent raters. The mean mismatch between the 3D images and the photographs was 2 mm. CONCLUSIONS: While our findings need confirmation on larger samples including patients with anterior epilepsy, this procedure allowed to localize subdural electrodes and to establish the spatial relationship of each electrode to the underlying brain structure, either normal or damaged, on brain convessity, basal and medial cortex. SIGNIFICANCE: Being simple, rapid, unexpensive, and reliable, this procedure holds promise to be useful to optimize epilepsy surgery planning. 相似文献
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We studied the significance of free erythrocyte protoporphyrin (FEP) in relation to iron status, aluminum levels and anemia in uremic patients on chronic dialysis. All but 1 patient showed high FEP values closely related to the degree of anemia. Increased FEP levels are due to a defective heme synthesis, not related to iron deficiency or aluminum overload. Treatment of anemia with recombinant human erythropoietin reduced FEP values. We therefore hypothesize that recombinant human erythropoietin ameliorates an enzymatic defect in heme synthesis. 相似文献
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The synthesis and localization of alternatively spliced fibronectin EIIIB in resting and thrombin-treated megakaryocytes 总被引:1,自引:1,他引:0
There are several species of alternatively spliced fibronectin (FN). One of these, FN EIIIB, is primarily present in embryonic and in proliferating and migrating cells and is believed to be important for cell maturation. We have studied the synthesis, localization, and secretion of this FN isoform in isolated guinea pig megakaryocytes, nonmegakaryocytic bone marrow cells, and platelets. There was 7.5 times more general FN in megakaryocytes than in nonmegakaryocytic cells based on the analysis of equivalent amounts of protein. FN EIIIB was detected by Western blotting in megakaryocytes but not in nonmegakaryocytic cells present in bone marrow. Neither megakaryocytes nor platelets secreted FN EIIIB, while megakaryocytes secreted 25.3% +/- 4.6% general FN and platelets secreted about 61% general FN in response to thrombin. Analysis of immunostained cells by confocal microscopy revealed that FN EIIIB had been redistributed to the surface of megakaryocytes in response to thrombin. Synthesis was studied by metabolic labeling, and megakaryocytes were shown to synthesize FN and FN EIIIB. Thus, megakaryocytes and platelets are among a small number of adult cells and tissues that synthesize and contain FN EIIIB. The expression of FN EIIIB on the megakaryocyte surface may influence migration and maturation. 相似文献
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Isolation of nontoxigenic Vibrio cholerae O group 1 from a patient with severe gastrointestinal disease. 总被引:6,自引:1,他引:6 下载免费PDF全文
J G Morris Jr J L Picardi S Lieb J V Lee A Roberts M Hood R A Gunn P A Blake 《Journal of clinical microbiology》1984,19(2):296-297
A nontoxigenic strain of Vibrio cholerae O group 1 was isolated in Florida from the stool of a patient with severe diarrhea. The strain had the same hemolytic and unique phage-sensitivity pattern as all toxigenic isolates from recent cases of cholera in Texas and Louisiana. Identical strains were transiently isolated from sewerage systems in two other Florida communities, suggesting that multiple human infections had occurred. This is the first indication that V. cholerae O1 strains which do not produce cholera toxin may be able to cause gastrointestinal disease in humans. The identification of these strains also raises questions about the relationship between toxigenic and nontoxigenic strains of V. cholerae O1 along the Gulf Coast of the United States. 相似文献
8.
Psychopathological dimensions of depression: a factor study of the 17-item Hamilton depression rating scale in unipolar depressed outpatients 总被引:1,自引:0,他引:1
BACKGROUND: Agreement on the factor structure of the Hamilton Depression Rating Scale (HDRS) has not been consistent among studies, and some investigators argued that the scale's factor structure is not reliable. This study aimed at shedding more light on this debated issue. METHODS: We studied 186 adults with unipolar depression (Major Depressive Disorder, n=80; Dysthymic Disorder, n=71; Depressive Disorder Not Otherwise Specified, n=25; Adjustment Disorder, n=10). They had no comorbid DSM-IV axis I or axis II disorders, and had received no treatment with antidepressant drugs in the previous 2 months. The factor structure of the scale was studied using the principal factor method, followed by oblique rotation. Factor scores were computed for each subject using the regression method. RESULTS: Using the scree-test criterion for factor extraction, we obtained a four-factor solution, explaining 43.8% of total variance. The four factors extracted were identified as (1) somatic anxiety/somatization factor; (2) a psychic anxiety dimension; (3) a pure depressive dimension; and (4) anorexia factor. Patients with Major Depressive Disorder scored significantly higher than patients with other diagnoses on the pure depressive dimension. LIMITATIONS: These results need to be replicated in different cultures, using analogous factoring techniques. CONCLUSIONS: Though not exhibiting factorial invariance in the stricter sense of the term, the 17-item HDRS did exhibit a relatively reliable factor structure. Our analysis provides further evidence that the scale is multidimensional. However, as long as the multidimensional character of the scale is taken into account the scale should be able to play a useful role in clinical research. 相似文献
9.
S CHAUDHURY PK CHAKRABORTY P BHARADWAJ M AUGUSTINE 《Medical Journal Armed Forces India》1994,50(1):59-60
A rare case of viral encephalitis in an 18 year old recruit who presented with signs of catatonic schizophrenia is reported.KEY WORDS: Viral encephalitis, Catatonic schizophrenia 相似文献
10.
Picardi N Di Rienzo M Annunziata A Bartolacci M Relmi F 《Annali italiani di chirurgia》1999,70(5):741-748
To remove the immerse portion of a cervical goitre it is necessary to treat preventively the cervical thyroid arteries. In most cases it is afterwards it is easy the blunt finger dissection of the mediastinal bulk following the correct cleavage plane and its dislodging in the cervical area. But in very rare instances, according also to the personal experience, remains some difficulty for the passage of a too bulky and hard mediastinal mass through the rigid limits of the upper thoracic outlet, or the immerse struma is too fragile for pulling it by transfixion threads. Therefore, traditionally arises the opportunity of an additional surgical access, through the breastbone or through the thoracic wall, according to the circumstances. Our experience, completely occasional but extremely positive of two of such cases, induces us to advance a proved alternative surgical proposal. When the difficulty of the removal of the immerse portion of the goitre comes only from the incongruence of the immerse volume and the rigid limits of the upper thoracic outlet, our proposal is that to obtain an amplification of the narrow passage breaking the continuity of the clavicle, by its section beneath the periostium near the breastbone and removing this sternal stump from the joint. The result is that of an widening of the upper thoracic outlet, no more rigid, and making easy the transit of the immerse portion from anterior mediastinum so dislodged in the neck. The rationale of this choice is that all is requested in such cases is only to overcome the obstacle of the incongruence among volume and bulk of the immerse portion and the bone limits fixed from the narrow upper thoracic outlet. Both the traditional sternotomy and the thoracotomy seems disproportional for this purpose, moreover with additional problems during the operation. The true advantage of these classical solutions is in treating under direct vision the anomalous arteries of the mediastinal goitre in cases of ectopic localization. But this is not the case of an immerse cervical goitre. It is therefore essential to note that this proposal applies only to the migrated goitre and not to the ectopic ones. The recovery is extremely simple, and both the aesthetics and the static of the scapular joint are not substantially compromised. 相似文献