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31.
M. Takada  T. Kono  S. T. Kitai 《Brain research》1992,590(1-2):311-315
Neurotoxic effects of flunarizine (Fz), a selective calcium channel blocker, on the nigrostriatal dopamine system was investigated. Systemic injections of Fz to mice resulted in a transient loss of tyrosine hydroxylase (TH) immunoreactive nigrostriatal neurons without cell loss. TH immunoreactivity in these neurons was greatly reduced as rapidly as one day after drug administration (regardless of dosage used) and thereafter recovered in both dose- and time-dependent manners. Such a novel neurotoxic action of Fz may constitute a morphological substrate for reversible drug-induced parkinsonian signs described in recent clinical case reports.  相似文献   
32.
改良超滤对婴幼儿心脏手术输血的影响   总被引:4,自引:1,他引:3  
目的 观察改良超滤技术在婴幼儿体外循环心血管手术中对输血及术后出血的影响。方法  6 0例接受体外循环下心血管手术的先天性心脏病患儿 ,均分为对照组 (不接受任何超滤 )、常规超滤组 (CUF组 )和改良超滤组 (MUF组 )。观察术中库血用量、血浆用量、血球压积的变化及术后2 4h出血量 ,并用SSPS/PC进行统计学处理。结果 MUF组库血用量、血浆用量、术后 2 4h出血量显著低于对照组和CUF组 (P <0 0 1) ,且滤出水量明显多于CUF组 (P <0 0 1)。结论 在婴幼儿心血管手术中 ,改良超滤可有效排出体内水分 ,提高血球压积 ,明显减少输血及术后出血 ,是节约用血的重要手段之一。  相似文献   
33.
BACKGROUND: Recalcitrant gingival erythematous lichen planus/lichenoid lesions comprise a considerable therapeutic problem. The objective of this study was to evaluate the therapeutic effect of grafting keratinized oral palatal mucosa to the sites of gingival lichen. METHODS: In 12 patients 20 grafts were transplanted to buccal gingival lesions. Mean age of the patients was 59.8 +/- 7.1 years (range 46-71 years). The mean observation time was 32 +/- 32.7 months (range 5-97 months). RESULTS: On a 4-point clinical grade scale (0-3), 12 (60%) transplants showed complete healing grade 3, six (30%) grade 2 and two (10%) grade 1. CONCLUSIONS: Using oral mucosal grafts from the palatal mucosa for the treatment of recalcitrant erythematous gingival lichen planus/lichenoid lesions seems to be a promising treatment modality.  相似文献   
34.
In glaucomatous eyes refractory to medication, laser techniques and conventional drainage surgery, intraocular pressure is often high, and visual loss rapid. In this situation a reliable, robust artificial outflow system is required. Molteno has evolved a plastic tube and plate device combined with a fibrosis suppression medication regimen. Thirty-eight eyes of 32 patients with uncontrolled glaucoma were treated with the Molteno system. Six months after operation mean intraocular pressure had been reduced from 41.0 ± 13.6 to 16.2 ± 5.6 mmHg. Eighteen eyes had pressures of 20 mmHg or less on no hypotensive therapy, 17 on reduced treatment. Three eyes had a pressure of 21 to 35 mmHg on treatment at six months. The 13 aphakic eyes responded as well as 25 phakic eyes. Five eyes with rubeotic glaucoma demonstrated pressures of less than 20 mmHg without therapy, four eyes with traumatic glaucoma required continuing medication with three having pressures below 22 mmHg. Of the seven eyes with uveitic glaucoma, one was lost, two required maintenance therapy; five of six surviving eyes had pressures below 20 mmHg. Fifteen eyes with congenital or juvenile glaucoma achieved pressures below 20 mmHg, three of these with timolol drops, three with timolol and acetazolamide, and nine with no treatment. While seven of seven eyes with refractory primary open-angle glaucoma attained pressures below 20 mmHg. all seven needed continuing mild hypotensive therapy. Eleven eyes underwent a one-stage procedure, while 27 eyes required a two-stage operation. Twenty-eight eyes received fibrosis suppression medication after the second stage, and 24 maintained or improved their preoperative visual acuity. Results have been encouraging: in general the Molteno system is recommended as the second drainage operation in all glaucomatous eyes in which conventional therapy has failed, and as the primary surgical procedure (after laser techniques) in eyes with rubeotic and uveitic glaucoma. Ciliary body destructive procedures should be restricted to control of symptoms in blind eyes.  相似文献   
35.
Summary A randomized prospective study was performed to compare the results of filtering surgery using a Limbusbased versus a Fornix-based conjunctival flap. The wound closure of the Fornix-based flap was performed using a running 10/0 nylon suture at the limbus. No statistical significant difference of IOP regulation was found between the two groups. There was a tendency of reduced occurrence of shallow anterior chamber and of less vascularized filtering blebs in the Fornix-based technique.  相似文献   
36.
Abstract The objective of the study was to evaluate the precision, concordance, practicability and the early clinical outcome of the use of a computerised navigation system in a comparative study with a group of 100 patients. Two groups of 50 patients each underwent implantation of a bicondylar knee prosthesis either by means of the freehand navigation system or by means of technical instrumentation. We found that the computerised navigation system provided a higher precision than the technically instrumented implantation: 94% of the prostheses implanted with the navigation system have an alignment within a range of -3° to 3° on of the Mikulicz line. Only 46% of the patients operated by means of the technical instrumentation reached this aspired result. Furthermore, the navigation system showed smaller ranges in the deviation of the aspired alignment. The radiological and computer-modeled alignment values differed both pre- and postoperatively, but to a larger extent before surgery. The varus or valgus deviations of the axis were more distinct radiologically under the weight of the patient’s body than in the computer model. The clinical outcome examined by the use of the HSS score after a mean followup of 7 months is good in both groups, and without significant differences. On average, the duration of surgery was 13 minutes longer in the computerised navigation group. We conclude that the benefit of the computerised navigation system is represented by the high improvement of precision. Achieving early clinical results identical to those in the technical instrumentation group, we expect a reduction of aseptic loosening in the computerised navigation group.  相似文献   
37.
A decrease of heteronymous median nerve-evoked inhibition of corticospinal projections to forearm extensor muscles was reported in a group of 10 dystonic patients by Bertolasi and colleagues in 2003. Here we tested the excitability of corticomotoneuronal connections to both wrist extensor (ECR) and flexor (FCR) muscles after conditioning stimulation of median and also radial nerve at rest in a group of 25 patients with focal hand dystonia compared to 20 healthy subjects. We also investigated the effect of the wrist dystonic posture, either in flexion or in extension, on the afferent modulation of ECR and FCR motor evolved potentials (MEPs). The heteronymous (median-induced) but also homonymous (radial-induced) inhibitions (interstimuli intervals 13-21 ms) of ECR MEP size observed in healthy subjects were decreased in patients. In addition, homonymous (median-induced) facilitation of FCR MEP size was also decreased in patients while heteronymous inhibition (radial-induced) was not. Neither the involvement of the target muscle in the dystonic posture nor the origin of the afferent volley (from a dystonic muscle) influenced the degree of impairment of afferent modulation of the MEP. These findings support the view that a global abnormal somatosensory coupling in focal hand dystonia may contribute to an inadequate motor command to wrist muscles.  相似文献   
38.
Depressive symptoms are common in patients with neurodegenerative disorders. Imaging studies suggest that a disruption of frontal-subcortical pathways may underlie depression associated with basal ganglia disease. This pilot study tested the hypothesis that frontal dysfunction contributes to depression associated with multiple system atrophy (MSA) and progressive supranuclear palsy (PSP). Depressed patients with MSA (n = 11), PSP (n = 9), and age-matched controls (n = 25) underwent measures of cerebral glucose metabolism applying positron emission tomography with (18)F-fluorodeoxyglucose. Regional metabolism in the patient groups was compared to the normal subjects using the voxel-based statistical parametric mapping. Depressive symptom severity (Hamilton Depression Rating) and degree of locomotor disability (Hoehn & Yahr) were assessed in the patient groups. The association between prefrontal metabolism and the occurrence of depressive symptoms and the degree of locomotor disability was investigated. When compared to controls, MSA patients revealed significant metabolic decreases in bilateral frontal, parietal, and cerebellar cortex and in the left putamen. In PSP patients, significant hypometabolism was demonstrated in bilateral frontal cortex, right thalamus, and midbrain. Depression severity but not the patients' functional condition was significantly associated with dorsolateral prefrontal glucose metabolism in both patient groups. The findings of this pilot study support the hypothesis that depressive symptoms in MSA and PSP are associated with prefrontal dysfunction.  相似文献   
39.
40.
BACKGROUND: Basal cell carcinoma (BCC) is a non-melanoma form of skin cancer that is frequently localized within the cervicofacial area. So far, little research is available on how patients perceive their facial aesthetics after surgical treatment for BCC. OBJECTIVES: To analyse (i) if there was a statistically significant improvement over time with regard to the perceived facial aesthetics of surgical patients; (ii) if there was a significant difference between primary and recurrent BCC patients; and (iii) between patients who had Mohs micrographic surgery (MMS) or surgical excision (SE). To assess (iv) which baseline perceptions and/or clinical parameters may predict the evaluation of facial aesthetics at 6 months after surgery. METHODS: Parallel to a clinical trial, a survey was carried out in which patients were asked, by means of a newly developed disease-specific questionnaire, about perceptions with regard to their facial aesthetics before and after surgery. RESULTS: Aesthetic perceptions of all surgical patients improved over time. There was no statistically significant difference on facial aesthetics between the group with a primary or recurrent BCC and patients treated with MMS or SE. Results also showed that the evaluation of postsurgical facial aesthetics can be predicted by both visibility of the tumour and preoperative perceptions. CONCLUSION: It is recommended to administer preoperatively a short questionnaire in which perceptions related to facial aesthetics are included. In doing so, physicians will become more familiar with the aesthetic problems patients might have regarding their afflicted facial site. Ultimately, it may help physicians in deciding whether patients will benefit from additional cosmetic procedures after surgery.  相似文献   
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