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381.
S Kasina JA Sanderson JN Fitzner A Srinivasan TN Rao LJ Hobson JM Reno DB Axworthy PL Beaumier AR Fritzberg 《Canadian Metallurgical Quarterly》1998,9(1):108-117
The precentral P22/N30 cortical component of the median nerve somatosensory evoked potentials (SEPs) was recorded in 16 patients (11 women and five men) suffering from cervical dystonia before and after botulinum toxin therapy. Cervical dystonia was diagnosed as idiopathic in all patients: 13 patients suffered from right-sided torticollis, and three suffered from left-sided torticollis. The amplitude of the P22/N30 component and the side-to-side ratio of amplitude values were measured. Normal values were obtained by acquiring measurements in two groups of healthy volunteers (n1 = 20 and n2 = 20). The recordings in the first control group were done with the patient's head in a normal position, whereas, in the second control group, the patient kept the head intentionally rotated 60 degrees to the right. Patients were treated with local injections of botulinum toxin A (BTX-A). The mean duration of treatment was 8.3 months, and the mean total amount of BTX injected was 295 U. The P22/N30 precentral component was repeatedly recorded in patients after head posture had been corrected to the normal plane by BTX-A treatment. The recordings showed that the amplitude of the P22/N30 precentral component recorded contralaterally to the direction of head deviation was significantly higher in patients before treatment than after treatment. Contralateral pretreatment amplitudes were also significantly higher (p < 0.01 and p < 0.05, respectively) than amplitudes in both groups of healthy volunteers. The mean side-to-side ratio of precentral P22/N30 component amplitudes was significantly higher in patients before treatment compared with after treatment and also compared with both control groups. These changes in dystonic patients probably reflect the direction of head rotation, the muscle pattern of torticollis, and the change in force of dystonic contraction after the treatment. The changes presumably could be the result of higher excitability of the precentral cortex contralateral to head rotation in patients with cervical dystonia and its change after successful BTX-A treatment. 相似文献
382.
AR Walker 《Canadian Metallurgical Quarterly》1998,11(3):146-147
Epileptic seizures are a known complication of uremia, but non-convulsive seizures appear to be rare. We describe a patient with absence status presenting with acute confusion who responded well to intravenous diazepam. Attention is drawn to this rare cause of acute confusional state in the hemodialysis population. 相似文献
383.
AR Tuguz MV Kiselevski? AM Buntsevich DV Komov BE Polotski? VA Normantovich IG Komarov EM Roshchin TS Golubeva SN Bykovskaia 《Canadian Metallurgical Quarterly》1996,121(2):192-195
Testicular germ cell tumour is said to be a model for curable neoplasm. However, the prognosis of primary extragonadal germ cell tumour does not appear to be as promising. Though similar in histology, the biology of primary extragonadal germ cell tumour is different as exemplified by the patients in this review. Eight patients with primary mediastinal germ cell tumours were treated with intensive cisplatin-based chemotherapy. All, except one, had non-seminomatous components. The poor prognosis of mediastinal germ cell tumour is due to a combination of poor treatment results with the cisplatin-based regimen and the development of non-germ cell and haematological malignancies. 相似文献
384.
385.
EO Costa AR Ribeiro PA Melville MS Prada AC Carciofi ET Watanabe 《Canadian Metallurgical Quarterly》1996,133(2):85-88
A survey of the prevention of disability policy and activities in a random sample of 200 ILEP assisted projects was conducted in 1995. This was followed by a workshop of field experts in different aspects of prevention of disability who work in different geographical regions. The survey findings and state of current knowledge on prevention of disability were reviewed during the workshop and recommendations on the planning, implementation, and evaluation of simple and effective prevention of disability developed. Prevention of disability includes complex activities, such as nerve decompression and reconstructive surgery, however these recommendations focus on the simple techniques and approaches which can be implemented through leprosy control programmes, primary health care and community-based rehabilitation. These recommendations have been approved by the ILEP Medical Commission, and reported in the ILEP Medical Bulletin (N degree 8, December 1995). 相似文献
386.
387.
Deciding advantageously in a complex situation is thought to require overt reasoning on declarative knowledge, namely, on facts pertaining to premises, options for action, and outcomes of actions that embody the pertinent previous experience. An alternative possibility was investigated: that overt reasoning is preceded by a nonconscious biasing step that uses neural systems other than those that support declarative knowledge. Normal participants and patients with prefrontal damage and decision-making defects performed a gambling task in which behavioral, psychophysiological, and self-account measures were obtained in parallel. Normals began to choose advantageously before they realized which strategy worked best, whereas prefrontal patients continued to choose disadvantageously even after they knew the correct strategy. Moreover, normals began to generate anticipatory skin conductance responses (SCRs) whenever they pondered a choice that turned out to be risky, before they knew explicitly that it was a risky choice, whereas patients never developed anticipatory SCRs, although some eventually realized which choices were risky. The results suggest that, in normal individuals, nonconscious biases guide behavior before conscious knowledge does. Without the help of such biases, overt knowledge may be insufficient to ensure advantageous behavior. 相似文献
388.
389.
Rheumatoid-like synovial lesions have been produced experimentally in 21% of rabbits receiving intravenous injections of bovine serum by various regimens. They were characterized by lining cell hyperplasia, accumulations, often follicular, of lymphocytes and plasma cells just under the lining layer, sometimes with extensive fibroplasia and pannus formation with cartilage erosion. 相似文献
390.
JK Shoemaker AR Kunselman DH Silber LI Sinoway 《Canadian Metallurgical Quarterly》1998,85(5):1793-1799
The impact of forearm blood flow limitation on muscle reflex (metaboreflex) activation during exercise was examined in 10 heart failure (HF) (NYHA class III and IV) and 9 control (Ctl) subjects. Rhythmic handgrip contractions (25% maximal voluntary contraction, 30 contractions/min) were performed over 5 min under conditions of ambient pressure or with +50 mmHg positive pressure about the exercising forearm. Mean arterial blood pressure (MAP) and venous effluent hemoglobin (Hb) O2 saturation, lactate and H+ concentrations ([La] and [H+], respectively) were measured at baseline and during exercise. For ambient contractions, the increase (Delta) in MAP by end exercise (DeltaMAP; i.e., the exercise pressor response) was the same in both groups (10.1 +/- 1.2 vs. 7.33 +/- 1.3 mmHg, HF vs. Ctl, respectively) despite larger Delta[La] and Delta[H+] for the HF group (P < 0.05). With ischemic exercise, the DeltaMAP for HF (21.7 +/- 2.7 mmHg) exceeded that of Ctl subjects (12.2 +/- 2.8 mmHg) (P < 0.0001). Also, for HF, Delta[La] (2.94 +/- 0.4 mmol) and Delta[H+] (24.8 +/- 2.7 nmol) in the ischemic trial were greater than in Ctl (1.63 +/- 0.4 mmol and 15.3 +/- 2.8 nmol; [La] and [H+], respectively) (P < 0.02). Hb O2 saturation was reduced in Ctl from approximately 43% in the ambient trial to approximately 27% with ischemia (P < 0.0001). O2 extraction was maximized under ambient exercise conditions for HF but not for Ctl. Despite progressive increases in blood perfusion pressure over the course of ischemic exercise, no improvement in Hb O2 saturation or muscle metabolism was observed in either group. These data suggest that muscle reflex activation of the pressor response is intact in HF subjects but the resulting improvement in perfusion pressure does not appear to enhance muscle oxidative metabolism or muscle blood flow, possibly because of associated increases in sympathetic vasoconstriction of active skeletal muscle. 相似文献