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21.
In this study we treated 6 patients with epidermotropic cutaneous T cell lymphoma (CTCL) with intermediate doses of recombinant alpha 2a interferon (18-100 x 10(6) IU/week) for 2-6 months. One patient experienced complete clinical remission in spite of a persistent dense lymphocytic skin infiltrate. One patient was markedly improved and 2 patients were moderately improved. The clinical condition of the 2 remaining patients was unchanged by interferon treatment. In all cases lesions relapsed a few weeks after treatment was discontinued. This study shows that interferon can be used to treat epidermotropic CTCL. However, a 2- to 6-month treatment using moderate doses did not lead to the high percentage of remission previously reported by others with high doses of recombinant alpha 2a interferon, for longer periods. This result suggests that interferon should be used at high doses and/or for long time periods for clinical improvement of CTCL patients.  相似文献   
22.
Selective attention to facial emotion and identity in schizophrenia.   总被引:4,自引:0,他引:4  
The selective attention to facial emotion and identity was investigated in 12 patients with schizophrenia and 12 healthy participants. Both patients and controls were required to perform two classification tasks (according either to identity or emotion). Two separate values for identity (person A/person B) and for emotion (fear/anger) were used. When the classification task was on one dimension, the other dimension was either correlated, constant, or orthogonal (Garner WR. The Processing of Information and Structure. Potomac, MD: Erlbaum, 1974, Garner WR. Interaction of stimulus dimensions in concept and choice processes. Cognitive Psychology 1976;8:98-123). Results indicated that both patients and healthy participants had an asymmetrical pattern of performance: they were able to selectively attend to the identity of the face presented, regardless of the emotion expressed on the face, but variation in identity interfered with the classification of facial emotion. Moreover, a correlational study indicated that the identity interference on emotion classification for schizophrenic patients covaried with the severity of their negative symptoms. The selective attention competencies in schizophrenia and the independence hypothesis of emotion and face recognition are discussed in the framework of current face recognition models.  相似文献   
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A radio-immunoassay (RIA) was used to screen for specific IgE to myorelaxants. Alcuronium was coupled to epoxy-activated Sepharose. Sixteen patients with anaphylaxis to alcuronium (n = 2), gallamine (n = 2) or suxamethonium (n = 12) were studied. The diagnosis was established by intradermal tests (ID), passive cutaneous anaphylaxis tests and human basophil degranulation tests. The amount of non specific label retained by Sepharose-ethanolamine (with sera of patients) and Sepharose-alcuronium (with sera of 11 control subjects) was estimated. The RIA was positive 10/16 (8/14 patients having reacted to a muscle relaxant other than alcuronium). The RIA seemed to be useful in the diagnosis of anaphylaxis to muscle relaxants. Drug-reactive antibodies were specific of the quaternary ammonium radical, which was the common allergenic determinant of all molecules of muscle relaxants. This test accounted for in vitro cross-reactivity, but had no predictive value for the clinical risk of crossed-anaphylaxis. This risk was best assessed by ID; it was positive in three cases. Although it was not possible to compare ID and RIA, the interpretation of which was different, both tests should be recommended for the detection of sensitivity to muscle relaxants.  相似文献   
25.
The polymerization of lactides with various D /L enantiomeric compositions using achiral Schiff's base/aluminium methoxide as initiator (SALENAlOCH3) in dichloromethane solution at 70°C is reported. The conversion was kept below 70% in order to limit transesterification reactions. The polymers obtained after precipitation show a narrow molecular weight distribution (ratio of weight- to number-average molecular weights M w/M n = 1,1–1,2) and an optical rotation higher than that expected from the optical purity of the starting monomers. The examination of the thermal properties reveals that whatever their enantiomeric composition all the prepared polymers are crystalline. This unusual behavior is explained by an end-chain propagation mechanism producing stereocopolymers with long enantiomeric sequences, i.e., increased isotacticity as substantiated by an examination of the microstructure of the polymers by means of 13C nuclear magnetic resonance. A stereocomplex formation was observed for stereocopolymers with optical purities below 40%.  相似文献   
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We developed a technique that allows the routine integration of PET in stereotactic neurosurgery, including radiosurgery. We report our clinical experience with the combined use of metabolic (i.e., PET) and anatomic (i.e., MRI and CT) images for the radiosurgical treatment of brain tumors. We propose a classification describing the relative role of the information provided by PET in this multimodality image-guided approach. METHODS: Between December 1999 and March 2003, 57 patients had stereotactic PET as part of their image acquisition for the planning of gamma knife radiosurgery. Together with stereotactic MRI and CT, stereotactic PET images were acquired on the same day using either (18)F-FDG or (11)C-methionine. PET images were imported in the planning software for the radiosurgery dosimetry, and the target volume was defined using the combined information of PET and MRI or CT. To analyze the specific contribution of the PET findings, we propose a classification that reflects the strategy used to define the target volume. RESULTS: The patients were offered radiosurgery with PET guidance when their tumor was ill-defined and we anticipated some limitation of target definition on MRI alone. This represents 10% of the radiosurgery procedures performed in our center during the same period of time. There were 40 primary brain lesions, 7 metastases, and 10 pituitary adenomas. Abnormal PET uptake was found in 62 of 72 targets (86%), and this information altered significantly the MRI-defined tumor in 43 targets (69%). CONCLUSION: The integration of PET in radiosurgery provides additional information that opens new perspectives for the optimization of the treatment of brain tumors.  相似文献   
29.
Background. Head and neck squamous cell carcinomas (HNSCC) present variable aggressiveness and chemosensitivity. Because the glutathione (GSH) system and thymidylate synthase (TS) are involved in the resistance to the main drugs used in HNSCC (cisplatin and 5-FU), we studied these systems in tumors and normal mucosae. Methods. Tumor samples and normal adjacent mucosae were collected from 37 untreated HNSCC patients. GSH and glutathione S-transferase (GST) activity were assayed by spectrophotometry, whereas TS activity and folates were determined by radioassays. Results. Mean GSH levels were higher in tumors (15.2 ± 8.2 nmol/mg protein) than in mucosae (8.3 ± 4.1 nmol/mg protein) (p = 0.005, paired t test). GST activity was also higher in tumors (394 ± 194 nmol/min/mg protein) than in mucosae (261 ± 132 nmol/min/mg protein) (p = 0.0003). TS activity was markedly higher in tumors (9.2 ± 21.5 pmol/min/mg protein) compared to that of mucosae (0.9 ± 1.2 pmol/min/mg protein) (p = 0.0001). Folate levels in tumors and mucosae were similar (1.2 ± 1.1 and 0.8 ± 0.9 pmol/mg protein, respectively; p = 0.1, NS). In relation to clinical stage and tumor size, a statistical difference was found in GSH and GST values between tumors and mucosae for stage IV and T3/T4. The increase in tumor TS compared to that of mucosae was significant for all clinical stages, tumor sizes, and nodal involvement. Conclusions. These data enhance our understanding of the enzymatic systems involved in cisplatin and 5-fluorouracil (5-FU) resistance in HNSCC and normal mucosae and may help to elucidate tumor behavior and interpatient differences in drug sensitivity. © 1994 John Wiley & Sons, Inc.  相似文献   
30.
Extracorporeal shockwave lithotripsy (ESWL) has been initially designed for stones located in the kidney and the upper ureter. Our lithotripter is no exception. Its components (the table and the orientation of the semi-ellipsoid reflector) are adapted for the treatment of kidney or lumbar ureter stones. However, the elements forming the unit of treatment (the table, the C-arm and the Tripter) can be modified in such a way that focalization of stones of the lower ureter becomes possible through a perineal exposure. The aim is to avoid the pelvic bone shield while a good focalization of the stone is realized. From June 1989 to March 1991, 35 patients were treated for distal ureteric stones by ESWL in this original positioning.  相似文献   
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