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排序方式: 共有1022条查询结果,搜索用时 15 毫秒
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Ozlem Coskun Serap Ucler Leyla Cavdar Levent E Inan 《Journal of clinical neuroscience》2007,14(4):334-339
Discontinuation of medication is the treatment of choice for patients with chronic daily headache (CDH) who overuse their medications. This treatment may be difficult due to increased headache severity observed in patients immediately after withdrawal. We retrospectively evaluated the efficacy of valproic acid therapy in 66 patients with overuse of CDH medication during withdrawal therapy. Patients were all withdrawn from medications and valproic acid started at 250 mg or 500 mg daily. Forty-two (63.6%) patients had decreased headache severity, including 27.3% objective responses in the first week. At the last visit in the 12th week, 50 patients were headache-free and only one patient had persistent headache. Fifteen patients withdrew from therapy due to side effects and lost to follow-up within this timeframe. Thus, low dose valproic acid appears to be safe and effective in the management of withdrawal therapy. 相似文献
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In this study, Doppler signals recorded from ophthalmic artery of 75 subjects were processed by PC-computer using classical and model-based methods. The classical method (fast Fourier transform) and three model-based methods (Burg autoregressive, moving average, least-squares modified Yule–Walker autoregressive moving average methods) were selected for processing ophthalmic arterial Doppler signals with uveitis disease. Doppler power spectra of ophthalmic arterial Doppler signals were obtained by using these spectrum analysis techniques. The variations in the shape of the Doppler spectra as a function of time were presented in the form of sonograms in order to obtain medical information. These Doppler spectra and sonograms were then used to compare the applied methods in terms of their frequency resolution and the effects in determination of uveitis disease. 相似文献
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Doppler ultrasound is known as a reliable technique, which demonstrates the flow characteristics and resistance of ophthalmic arteries. In this study, ophthalmic arterial Doppler signals were obtained from 106 subjects, 54 of whom suffered from ocular Behcet disease while the rest were healthy subjects. Multilayer perceptron neural network (MLPNN) employing delta-bar-delta training algorithm was used to detect the presence of ocular Behcet disease. Spectral analysis of the ophthalmic arterial Doppler signals was performed by least squares (LS) autoregressive (AR) method for determining the MLPNN inputs. The MLPNN was trained with training set, cross validated with cross validation set and tested with testing set. All these data sets were obtained from ophthalmic arteries of healthy subjects and subjects suffering from ocular Behcet disease. Performance indicators and statistical measures were used for evaluating the MLPNN. The correct classification rate was 96.43% for healthy subjects and 93.75% for unhealthy subjects suffering from ocular Behcet disease. The classification results showed that the MLPNN employing delta-bar-delta training algorithm was effective to detect the ophthalmic arterial Doppler signals with Behcet disease. 相似文献
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To compare morphological changes in the umbilical cords from chronic hypertensive and preeclamptic patients having normal or pathological umbilical artery Doppler ultrasonographic results. Umbilical cords from 34 normotensive, 31 chronic hypertensive and 70 preeclamptic women with normal and abnormal Doppler flow velocity waveforms (FVW) at 35-40 gestational weeks were studied. Morphological changes in the umbilical cords were examined on formalin-fixed, paraffin-embedded sections. The total umbilical cord area, total vessel area, and wall thickness of umbilical vessels were measured in systematic random samples using unbiased stereology methods. An ANOVA test was used for statistical analysis. In the chronic hypertensive and preeclamptic groups with normal Doppler FVW, the thickness of the umbilical cord vessels remained nearly constant, whereas both the total area and the lumen area were reduced. These changes correlate with the histopathological findings, suggesting a mainly vasoconstrictive effect. By contrast, analysis of the preeclamptic group with pathologic Doppler FVW showed a comparable reduction of all parameters of the umbilical cord. Histopathological findings were related to smaller, contracted smooth muscle cells of the vessel wall, which is suggestive of a predominant hypoplastic mechanism. As a result of reduced uteroplacental perfusion, fetal hypoxia and intrauterine growth retardation become unavoidable in preeclampsia. The histopathological changes in the umbilical cord between the chronic hypertensive and preeclamptic patients depend on the Doppler results. In conclusion, the umbilical artery Doppler FVW indices provide good values for predicting intrauterine growth retardation in preeclamptic patients. 相似文献
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Cadavers remain a principal teaching tool for anatomists and medical educators teaching gross anatomy. Infectious pathogens in cadavers that present particular risks include Mycobacterium tuberculosis, hepatitis B and C, the AIDS virus HIV, and prions that cause transmissible spongiform encephalopathies such as Creutzfeldt-Jakob disease (CJD) and Gerstmann-Straussler-Scheinker syndrome (GSS). It is often claimed that fixatives are effective in inactivation of these agents. Unfortunately cadavers, even though they are fixed, may still pose infection hazards to those who handle them. Specific safety precautions are necessary to avoid accidental disease transmission from cadavers before and during dissection and to decontaminate the local environment afterward. In this brief review, we describe the infectious pathogens that can be detected in cadavers and suggest safety guidelines for the protection of all who handle cadavers against infectious hazards. 相似文献
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The effects of acetylcholine and propolis extract on corneal epithelial wound healing in rats. 总被引:2,自引:0,他引:2
PURPOSE: To investigate the effects of topical acetylcholine and topical administration of propolis, a natural beehive product, on corneal epithelial wound healing. METHODS: The whole corneal epithelium was debrided in 42 eyes of 21 rats by mechanical scraping with a dulled scalpel blade. Animals were divided into three groups. Group 1 received topical 1% water extract of propolis (WEP), group 2 received topical acetylcholine (ACh), and group 3 (control group) received topical phosphate-buffered saline, 6 times a day for 3 days, starting immediately after debridement. The area of the corneal epithelial defect was stained with fluorescein, photographed, and then measured every 12 h. The mean epithelial defect area and the mean percentage of epithelial defect remaining at each follow-up were compared between the groups. RESULTS: The mean epithelial defect area and the mean percentage of epithelial defect remaining at each time were significantly smaller (p < 0.001, p < 0.05, respectively) in the ACh and propolis groups as compared with control groups. There was no statistically significant difference between the propolis or ACh groups at any time (p > 0.05). At 72 h, the mean percentage of defect remaining was 2.58% in the ACh group, 1.3% in the propolis-treated group, and 8.68% in the control group. CONCLUSIONS: This study demonstrated that ACh and propolis facilitated corneal epithelial wound healing of rats. Although the mechanisms of the effect of propolis on wound healing and its clinical use still remain to be determined, ACh may have a place in the treatment of corneal epithelial injuries. 相似文献
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Titap Yazicioglu Rahsan Inan Anl Agakesen Murat Oklar Saban imek 《Indian journal of ophthalmology》2022,70(6):2094
Purpose:Functional epiphora is a clinical condition that presents with the complaint of watery eyes, but without anatomical stenosis in the lacrimal drainage system. Although the mechanism is not clear, there are various possibilities involving the movement of the orbicularis oculi muscle, especially its deeper segment (Horner’s muscle). We aimed to evaluate the function of the orbicularis oculi muscle in patients with patent, but dysfunctional lacrimal drainage system using a quantitative motor unit potential (MUP) analysis.Methods:Twenty-eight patients with functional epiphora (mean age = 59 years) and a control group of 28 volunteers were included in the study. Inclusion criteria were persistent and symptomatic epiphora or wiping >10 times per day and diagnosis confirmation by lacrimal irrigation test. Electromyography (EMG) was performed on the deeper segment of the orbicularis oculi muscle (medial and lateral parts). MUP parameters (duration time, amplitude, number of phases, number of turns, area, rise time, and thickness) were evaluated in both groups. Any increase in amplitude, prolongation time (>14 ms), number of turns, and satellite potential was taken as characteristic of the neurogenic type of epiphora, whereas shortened motor unit duration time, increased phase number, and low amplitude are the features of myopathic type.Results:Upon MUP analysis of the medial and lateral orbicularis oculi muscle, the increase in duration and thickness values in the medial part and the increase in duration, amplitude, area, and thickness values of the lateral part were found to be statistically significant in the patient group compared to the control group (P < 0.001). In the evaluation of the patients’ medial and lateral orbicularis oculi muscle, the increase in phase values and decrease in amplitude, area, and rise time values were found to be statistically significant (P = 0.024, P < 0.001, P < 0.001, and P = 0.010, respectively).Conclusion:These data show that functional epiphora is due to neurogenic damage of the orbicularis oculi muscle and should be investigated in more detail. 相似文献