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Somatosensory evoked magnetic fields and electrical potentials were measured in eight patients with unilateral neuropathic pain. After median nerve stimulation on the painful side, the amplitudes of the evoked responses were enhanced 2 to 3 times at a latency of about 100 ms compared to the responses of the contralateral, unaffected side. After posterior tibial nerve stimulation an enhancement was found at latencies around 110 ms and 150 ms. The scalp distribution of the magnetic field at the latencies of abnormal responses was dipolar and the responses could be ascribed to a current dipole. Three (of the eight) patients underwent spinal cord stimulation (SCS) for their pain. The enhancement of the evoked responses to stimulation of the painful side decreased after spinal cord stimulation. After a long period of spinal cord stimulation only (e.g., a year) during which the patient reported to be pain free, these abnormal responses were no longer observed.  相似文献   
44.
Adenovirus (Ad) isolates from a large number of human immunodeficiency virus (HIV)-infected individuals were compared serologically and genetically with Ad isolates from immunocompetent patients. Between 1982 and 1994, stool and urine samples from 137 subjects with AIDS hospitalized in The Netherlands yielded 143 Ad strains. Forty additional Ad strains were obtained from 35 HIV-positive patients in Manchester, United Kingdom, in 1992 and 1993. Of these 183 HIV-associated Ad strains, 84% belonged to species D and 3% belonged to species C. These strains were compared with 2,301 Ad strains collected during general diagnostic examinations in The Netherlands from 1973 to 1992. Of the latter strains, 5% belonged to species D and 49% belonged to species C. Two of the Ads isolated from fecal specimens of AIDS patients represent new serotypes: candidate Ad serotype 50 (prototype strain, Wan) of subspecies B1 and candidate Ad serotype 51 (prototype strain, Bom) of species D. The DNA restriction enzyme patterns of strains Wan and Bom differed from the patterns of all established prototypes.  相似文献   
45.
We obtained follow-up data on 22 sets of twins where at least one twin had Alzheimer's disease (AD). The concordance rate for monozygotic twins (n = 17 pairs) was 59%, whereas that for dizygotic twins was 40%. In our series 8 monozygotic twins had hysterectomies; all had AD. The twins with hysterectomies also had a tendency to develop AD at an earlier age than their co-twin. Five twins with serious systemic infection developed AD, and they tended to have earlier onset than their corresponding twin. We found no strong evidence that head injury predisposed to AD.  相似文献   
46.
During a 2-year period, 34 patients of catatonic features in Chinese ethnic background Taiwanese were brought to the emergency unit of Chang Gung Memorial Hospital at Linkou. The ratios of the causes of catatonic features by schizophrenic disorders, mood disorders, neuroleptic-induced disorders, and general medical conditions were 26, 9, 24 and 41%, respectively. After the treatments of antipsychotics, benzodiazepam, or electroconvulsive therapy (ECT), 24 patients (70.6%) showed complete remission, seven patients (20.6%) showed partial remission, and three patients (8.8%) showed no response (two died). Additionally, a suggestive period is proposed in order to distinguish acute and insidious onset catatonic conditions to help clinicians in deciding on probability immediately. The patients were grouped into four diagnostic categories; namely, schizophrenic disorders, mood disorders, neuroleptic-induced disorders, and general medical conditions for comparison. One-way ANOVA and Duncan's multiple-range test were used for continuous variables, and the Chi-squared test was used for categorical variables. The mean duration of 'insidious onset catatonic condition' (including schizophrenic disorders and general medical conditions) before seeking medical help was longer than 3.33 weeks, while the mean duration of 'acute catatonic condition' (including mood disorders and neuroleptic-induced disorders) was shorter than 1.83 weeks. These findings suggest that 2-3 weeks would be a cut-off point for acute or insidious onsets of catatonic conditions.  相似文献   
47.
This feasibility study was performed to evaluate the suitability of MRI in defining appropriate pelvic radiotherapy treatment volumes, and to compare MRI sequences with CT for prostate cancer radiotherapy. Five patients with localized prostate cancer, imaged with four MRI sequences (spin echo (SE) T1, turbo SE (TSE) T2, high resolution TSE (HR) T2, and FLASH 3D (F3D)), compared with their corresponding CT planning scans. Segmentation ability of the following pelvic structures: prostatic apex (PA), prostate, rectum, bladder and seminal vesicles (SV), were evaluated by three independent observers. They used a five point grading scale based on the anatomical definition of the organ boundary, tissue contrast and multiplanar display. Results were averaged for the group and for each sequence. There was no significant interobserver variation in the assessed scores (p > 0.1). The average scores (+/- 1 SD) for all pelvic structures assessed by each imaging sequence were CT 1.3 +/- 0.6; SE T1 2.4 +/- 0.9; TSE T2 2.4 +/- 0.7; HR T2 2.2 +/- 0.7 and F3D 3.4 +/- 0.6. Compared with CT, the average MR score for each assessed pelvic structure was higher with a trend for all transaxial MR sequences to provide improved segmentation of the PA and rectum. The F3D sequence scored highest as it provided multiplanar views and avoided the problem of partial volume averaging. MRI, compared with CT, appears to provide improved definition of pelvic treatment volumes but further work is required to confirm this and to address the issues of MRI associated distortion and dosimetry before MRI can be used routinely for pelvic radiotherapy planning.  相似文献   
48.
Mesenteric ischaemia is a rare but serious cause of abdominal pain. We present the case of a man with Sneddon's syndrome, who had symptomatic mesenteric ischaemia secondary to a superior mesenteric artery stenosis in conjunction with a hepatic artery stenosis. As far as the authors are aware, this has not previously been described in Sneddon's syndrome, which is a vascular systemic disease characterized by an association between cerebrovascular accidents and a livedo reticularis skin rash. He was treated with balloon angioplasty and stent insertion, with good symptomatic improvement. This has implications for other stenoses in this condition should they become symptomatic.  相似文献   
49.
Low doses of oxytocin facilitate social recognition in rats   总被引:7,自引:0,他引:7  
Social recognition of juveniles by adult male residents has been shown to be modulated by neurohypophyseal hormones. The decrease of social investigation behavior during a second encounter with the same juvenile serves as index for social recognition. In the present study it was found that low doses (0.09–6.0 ng · kg–1) of oxytocin (OXT) given subcutaneously dose dependently facilitated social recognition. The effect of OXT appeared specific, since no change in social investigation was found when a novel juvenile was tested during the second encounter. No disturbances of social recognition by the low doses of OXT could be detected, in contrast to higher doses of this hormone. Other neurohypophyseal hormones, vasopressin and vasotocin, did not facilitate social recognition when tested in the same range of low doses.  相似文献   
50.
The effects on social recognition memory of (Arg(8))-vasopressin (AVP-(1-9), [pGlu(4), Cyt(6)]AVP-(4-8) and oxytocin locally administered into the rat's septum were investigated. In the behavioural paradigm used, a juvenile intruder was presented to an adult resident male rat twice for 5 min, with an inter-exposure interval of 120 min. Peptide-free residents investigated the juvenile during the second encounter as long as during the first encounter. Intraseptal injection just after the first encounter with graded doses of (Arg(8))-vasopressin, [pGlu(4),Cyt(6)]AVP-(4-8) or oxytocin caused a decrease of social investigation, as compared to placebo treatment, indicating facilitation of social recognition. The least effective dose was 100pg, 200pg and 300pg respectively. The action of vasopressin was blocked by both d(CH(2))(5)[Tyr(Me)(2)]AVP and d(CH(2))(5)[D-Ile(2)Ile(4)]AVP, V(1) and V(2) vasopressinergic receptor antagonists, but not by desGly(NH(2))(9)-d(CH(2))(5)[Tyr(Me)(2)Thr(4)]-OVT, an oxytocinergic receptor antagonist. None of the antagonists blocked the oxytocin-facilitating action on social recognition. They also did not affect social recognition when injected alone. The effects of vasopressin seem to be mediated by vasopressinergic receptors dissimilar to those found in the periphery, while the receptors involved in the action of oxytocin remain to be elucidated.  相似文献   
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