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991.
Our objective was to determine the natural history and prognostic factors of familial forms of cerebral cavernous malformations (CCM). Cavernomas are one of the most common central nervous system vascular malformations. Familial CCM is increasingly diagnosed, but little is known about its natural history. In a national survey, we analysed clinical and MRI features of 173 patients from 57 unrelated French families. Of these 40 had undergone at least two clinical and MRI examinations. Occurrence of haemorrhage, new lesions, change in signal intensity and size of lesions have been studied by comparison between first and last MRI studies. The CCM were classified according to Zabramski et al. Mean follow-up was 3.2 years (range 0.5–6.5 years). We followed 232 cavernomas (mean 5.9 per patient, range 1–17). Serial MRI demonstrated changes in 28 patients (70 %). Bleeding occurred in 21 lesions (9.1 %) in 14 patients (35 %). The haemorrhagic risk was 2.5 % per lesion-year, higher in type I and brain-stem CCM. We saw 23 new lesions appear in 11 patients (27.5 %), with an incidence of 0.2 lesions per patient year. Signal change was observed in 11 patients (27.5 %), in 14 lesions (6 %), while 9 lesions (3.9 %) in 9 patients (22.5 %) changed significantly in size. Received: 20 May 1999/Accepted: 1 September 1999  相似文献   
992.

Purpose  

A variety of templates are being used for mandible reconstruction with free flaps. We describe a simple and cost effective method using a ‘K’ wire template for the central segment reconstruction of the mandible with free fibula flap.  相似文献   
993.
994.
《Clinical neurophysiology》2020,131(5):1102-1118
ObjectiveStroke lesions in non-auditory areas may affect higher-order central auditory processing. We sought to characterize auditory functions in chronic stroke survivors with unilateral arm/hand impairment using auditory evoked responses (AERs) with lesion and perception metrics.MethodsThe AERs in 29 stroke survivors and 14 controls were recorded with single tones, active and passive frequency-oddballs, and a dual-oddball with pitch-contour and time-interval deviants. Performance in speech-in-noise, mistuning detection, and moving-sound detection was assessed. Relationships between AERs, behaviour, and lesion overlap with functional networks, were examined.ResultsDespite their normal hearing, eight patients showed unilateral AER in the hemisphere ipsilateral to the affected hand with reduced amplitude compared to those with bilateral AERs. Both groups showed increasing attenuation of later components. Hemispheric asymmetry of AER sources was reduced in bilateral-AER patients. The N1 wave (100 ms latency) and P2 (200 ms) were delayed in individuals with lesions in the basal-ganglia and white-matter, while lesions in the attention network reduced the frequency-MMN (mismatch negativity) responses and increased the pitch-contour P3a response. Patients’ impaired speech-in-noise perception was explained by AER measures and frequency-deviant detection performance with multiple regression.ConclusionAERs reflect disruption of auditory functions due to damage outside of temporal lobe, and further explain complexity of neural mechanisms underlying higher-order auditory perception.SignificanceStroke survivors without obvious hearing problems may benefit from rehabilitation for central auditory processing.  相似文献   
995.
996.
997.
In this study, the effect of ripening stage (R), cultivar (C), bunch type (T), and location (L) on the variability of provitamin A carotenoids (pVACs) in 16 plantain cultivars grown in Cameroon and Gabon was investigated. For the sixteen plantain cultivars, fruits were collected at stages 1 (unripe), 5 (ripe), and 7 (overripe) from three different bunch types (French, False Horn, and True Horn) across 13 locations in Cameroon and Gabon. For all cultivars, the highest concentration of carotenoids was found in ripe pulp (p < 0.05). For bunch type, a higher level of pVACs was observed in the French type compared with the False Horn and True Horn types at all ripening stages. In addition, the concentration of pVACs at each ripening stage varied greatly across locations. In both countries, the interaction between the four factors, particularly between R × C, R × T, R × L, R × C × L, and R × T × L, contributed significantly (p < 0.05) to the variability of pVACs in plantain. Daily consumption of 100 g of ripe plantain could meet 36.2–101.7 % of the dietary reference intakes (DRIs) for children 1–5 years old, 20.7–58.1 % for adult women, and 16.1–45.2 % for adult men. These findings can serve as a guide to reducing vitamin A deficiency (VAD) in Africa.  相似文献   
998.
《中国现代医生》2020,58(12):184-192
光学相干断层扫描血管造影通过连续探测同一位置的血管内红细胞运动,生成三维血流信息,获取高分辨率的眼底血管图像。分频幅去相关血流成像演算技术,减少了因眼球轴向运动和组织运动产生的噪点及伪影,优化了信噪比,使得对毛细血管网的检测更具有连贯性。光学相干断层扫描血管造影目前已应用于糖尿病性视网膜病变、年龄相关性黄斑变性、视网膜血管阻塞、青光眼、中心性浆液性脉络膜病变等疾病的诊疗中,具有广阔的临床应用及科研前景。本文就光学相干断层扫描血管造影在眼底微血管定量分析中的应用作综合性论述。  相似文献   
999.
· Purpose: To evaluate whether ocular hypertensive subjects have a higher central corneal thickness than other individuals. · Methods: In this prospective study, 48 subjects with ocular hypertension, 63 patients with open-angle glaucoma, 56 nonglaucomatous patients with diabetes mellitus, and 106 control subjects were evaluated. Corneal thickness was measured by ultrasound pachymetry, and intraocular pressure was determined by Goldmann applanation tonometry. · Results: Central corneal thickness was significantly higher in the ocular hypertensive subjects, mean ±S.D., 592±39 μm, than in the patients with glaucoma (536±34 μm), the nonglaucomatous patients with diabetes mellitus (550±31 μm), and the normal subjects (545±33 μm), P<0.001. The three latter groups did not vary significantly in central corneal thickness, P>0.05. · Conclusion: In some individuals with increased transcorneal measurements of intraocular pressure, the cornea is thicker than in subjects with normal intraocular pressure readings or patients with glaucoma. It suggests that in ocular hypertensive subjects, corneal pachymetry should be performed to rule out an abnormally thick cornea as a reason for falsely high measurements of intraocular pressure. Received: 14 April 1998 Revised version received: 10 July 1998 Accepted: 23 July 1998  相似文献   
1000.

Background

The purpose of this study was to determine if laterality of internal jugular vein (IJV) sampling affects the accuracy of intraoperative parathyroid hormone (PTH) monitoring during parathyroidectomy for primary hyperparathyroidism.

Methods

In this study, 109 patients underwent parathyroidectomy (82 with unilateral disease, 27 with multigland disease). PTH samples were taken from both the left and the right IJV at these time points: preincision (baseline) and then at 5, 10, and, in selected patients, 20 minutes after excision. The Miami criterion was used to determine operative success.

Results

In all 109 patients combined, the mean decreases in intraoperative PTH levels were 73.8 ± 22.2% for the left IJV and 71.9 ± 23.0% for the right IJV (P = .22). The Miami criterion was met in 105 patients: in 100 (95%) left IJV samples and 99 (94%) right IJV samples (P = 1.00).

Conclusions

No difference was found in the accuracy of intraoperative PTH monitoring between patients' left and right IJV samples. Central venous laterality did not affect fulfillment of the Miami criterion.  相似文献   
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