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61.
Operationsprinzip Obwohl sich weniger invasive Methoden der Synovektomie, wie zum Beispiel die radiochemische oder arthroskopische Vorgehensweise, zunehmender Beliebtheit erfreuen, bleibt die offene operative Behandlung einer schweren Synovialitis des Kniegelenks, selbst in weit fortgeschrittenen F?llen, die Methode der Wahl. Die Entfernung der chronisch-entzündlich ver?nderten Membrana synovialis scheint die Lokalsituation in der Mehrzahl der F?lle unter Kontrolle zu bringen. Die offene Synovektomie sollte nicht bei weitgehend zerst?rtem Gelenk mit signifikantem Knorpel-Knochen-Verlust der Gelenkoberfl?chen durchgeführt werden. überarbeitete Fassung aus: Orthop. Traumatol. 2 (1993), 244–250 (englische Ausgabe).  相似文献   
62.
Multiple reports of cauda equina syndrome and transient radicular nerve root irritation have suggested that lidocaine spinal anesthesia may be responsible. In this case report, a patient with a preexisting diabetic neuropathy received a partial block following a tetracaine spinal, which was followed by a lidocaine spinal. Following block resolution, a new conus medullaris syndrome was diagnosed. Because of the close proximity of the cauda equina and the conus medullaris, differentiation between these syndromes can be difficult. The preexisting diabetic neuropathy may have predisposed this patient to neurologic injury. The choice of a different local anesthetic drug with less neurotoxic potential such as bupivacaine may have prevented this injury.  相似文献   
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64.
Partial k-space sampling is frequently used in single-shot diffusion-weighted echo-planar imaging (DW-EPI) to reduce the TE and thereby improve the SNR. However, it increases the sensitivity of the technique to bulk rotational motion, which introduces a phase gradient across the tissue that shifts the echo in k-space. If the echo is displaced into the high spatial frequencies, conventional homodyne reconstruction fails, causing intensity oscillations across the image. Zero-padding, on the other hand, compromises the image resolution and may cause truncation artifacts. We present an adaptive version of the homodyne algorithm that detects the location of the echo in k-space and adjusts the center and width of the homodyne filters accordingly. The adaptive algorithm produces artifact-free images when the echo is shifted into the high positive k-space range, and reduces to the standard homodyne algorithm in the absence of bulk motion.  相似文献   
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66.
Cutaneous T-cell lymphoma   总被引:1,自引:0,他引:1  
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67.
The purpose of this study was to determine the suitability of MRI to accurately detect radiofrequency (RF) thermoablative lesions created under MR guidance. In vivo RF lesions were created in the livers of six New Zealand White rabbits using a 2-mm-diameter titanium alloy RF electrode with a 20-mm exposed tip and a 50-W RF generator. This was performed using a 0.2T clinical C-arm MR imager for guidance and monitoring. Each animal was sacrificed and gross evaluation was performed. Histologic correlation was performed on the first two animals. The MR-compatible RF electrode was easily identified on rapid gradient-echo images used to guide electrode placement. A single lesion was created in each rabbit liver. Lesions ranged from approximately 10 to 17 mm in diameter (mean, 13.5 mm). T2-weighted and short T1 inversion recovery (STIR) images demonstrated lesions ranging in diameter from 12 to 18 mm (mean, 14.6 mm). Lesion dimensions determined from images closely correlated with those determined at gross examination with the discrepancy never exceeding 2 mm, for an r2 value of .87. MRI performed at the time of MR-guided RF ablation accurately demonstrated created lesions. This modality may provide a new option for the treatment of local and regional neoplastic disease.  相似文献   
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69.
The authors completed a retrospective chart review of the records of all patients identified with diagnoses of mania and schizoaffective disorder, manic type, who underwent electroconvulsive therapy between the years 1973 and 1986 at McLean Hospital. Ten of 18 manic patients (56%) and 3 of 9 schizoaffective patients (33%) experienced meaningful clinical benefit. The authors report the correlation of treatment and patient factors with outcome and review the literature on the convulsive therapy of mania.  相似文献   
70.
The elicitation of violent of psychotic behavior by phencyclidine (PCP) administration is well documented. There are indications, however, that behavioral responses to PCP may differ among PCP users as a function of background or personality characteristics. The present study examined 35 male jail inmates with histories of PCP use. Estimates of the nature and extent of drug use and self-reports of previous psychiatric hospitalizations were obtained in these subjects. The Buss-Durkee Hostility Inventory was modified to reflect behaviors under the two simulated conditions of "No PCP" and "PCP" use. Results showed that PCP use was related to increased levels of hostility in our subjects when present age, age of first use, the frequency of use and suspicion and assaultive behavior when not using PCP was considered. Also, subjects with a history of psychiatric hospitalizations reported higher levels of assault when using PCP than those without psychiatric histories. These data suggest that the self-reported behavioral results of PCP use are associated with certain personality traits and background features.  相似文献   
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