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91.
92.
In this prospective study, we investigated the effects of hypofractionated radiotherapy for patients with high-grade gliomas. About 31 patients with glioblastoma multiforme or anaplastic astrocytoma were studied between October 2003 and December 2004. Hypofractionated radiotherapy (3 Gy/fraction/day) was delivered to a total dose of 45 Gy in 15 fractions in 10 patients (32%) who had total excision before radiotherapy and to a total dose of 54 Gy in 18 fractions in 21 patients (68%) who had subtotal excision or biopsy alone. Sex, age, type of surgery, tumor grade, Karnofsky performance status, time between surgery and initiation of radiotherapy, and total radiotherapy dose were analyzed as potential prognostic factors for survival using the univariate log-rank method. The median follow-up was 15 months (4–16 months). A total of 15 patients (48%) died of their illness; 16 patients (52%) were still alive at the last follow-up. The median survival time was 8 months. Actuarial 1–year overall survival was 40%. Type of surgery, timing of radiotherapy after surgery, and initial Karnofsky performance status were significant prognostic factors for survival. No grade 3–4 acute or late neurotoxicity was observed. The tolerance of patients to hypofractionated RT was not different from that for conventional radiotherapy. This treatment schedule can be used for patients with high-grade gliomas. Future investigations are needed to determine the optimal fractionation for high-grade gliomas.  相似文献   
93.
Sex is a biological variable that contributes to individual variability in brain structure and behavior. Neuroimaging studies of population-based samples have identified normative differences in brain structure between males and females, many of which are exacerbated in psychiatric and neurological conditions. Still, sex differences in MRI outcomes are understudied, particularly in clinical samples with known sex differences in disease risk, prevalence, and expression of clinical symptoms. Here we review the existing literature on sex differences in adult brain structure in normative samples and in 14 distinct psychiatric and neurological disorders. We discuss commonalities and sources of variance in study designs, analysis procedures, disease subtype effects, and the impact of these factors on MRI interpretation. Lastly, we identify key problems in the neuroimaging literature on sex differences and offer potential recommendations to address current barriers and optimize rigor and reproducibility. In particular, we emphasize the importance of large-scale neuroimaging initiatives such as the Enhancing NeuroImaging Genetics through Meta-Analyses consortium, the UK Biobank, Human Connectome Project, and others to provide unprecedented power to evaluate sex-specific phenotypes in major brain diseases.  相似文献   
94.
During the last 5 years 2057 children under the age of 5 with various neurologic symptoms with the suspected diagnosis of lysosomal storage diseases were referred to our hospital from different universities and state hospitals. We were able to separate sphingolipidoses by lysosomal enzyme screening. A total of 300 patients (15%) with sphingolipidoses were diagnosed; there were deficiencies of arylsulfatase A [metachromatic leukodystrophy (MLD)] in 93 (31%), hexosaminidase [Sandhoff disease (SHD)] in 62 (20.7%), hexosaminidase A [Tay-Sachs disease (TSD)] in 15 (5%), beta-galactosidase (GM1 gangliosidosis) in 35 (11.7%), alpha-galactosidase (Fabry disease) in one (0.3%) cerebroside beta-galactosidase (Krabbe disease) in 65 (21.7%) and glucosylceramidase (Gaucher disease) in 29 (9.6%). SHD (20.7%), MLD (31%) and Krabbe disease (21.7%) were common. Prenatal enzymatic diagnosis was made in 70 at risk pregnancies, 64 for TSD and SHD, three for MLD and three for GM1 gangliosidosis by using chorionic villus biopsy in 54, cord blood samples in 12 and cultured amniotic fluid cells in four. Seventeen fetuses were found to be affected. We have calculated the relative frequency and minimum incidence of sphingolipidoses in Turkey. The combined incidence of sphingolipidoses is 4.615 per 100,000 live births. The calculated incidences are 1.43, 0.95, 1, 0.23, 0.54, 0.45, 0.015 per 100,000 live births for MLD, SHD, Krabbe, Gaucher, TSD, GM1 gangliosidosis and Fabry diseases, respectively. The real incidence, which covers all subtypes of this group of diseases, should be greater than this number. The results suggested that, as a group, sphingolipidoses are relatively common and represent an important health problem in Turkey and some rare autosomal recessive diseases of Turkey are due to 'founder effect' created by consanguineous marriages.  相似文献   
95.
Evoked potentials in children with Wilson's disease   总被引:1,自引:0,他引:1  
We assessed multimodal evoked potentials (EPs) in 13 children with newly diagnosed neurologically symptomatic Wilson's disease (WD) and in their first degree symptom-free relatives, consisting of seven presymptomatic and 15 asymptomatic siblings and 22 asymptomatic parents. EP abnormalities of at least one modality and one side stimulation were observed in 38.5% of patients, 42.9% of presymptomatic siblings, 21.4% of asymptomatic siblings and 18.2% of parents. Patients tended to have more prolonged central latencies of EPs. However, the left I-V interpeak brainstem auditory EP latency difference was the only one to reach at the statistical significance (P = 0.001). Abnormal VEP P100 latency was detected more frequently in presymptomatic siblings than those in asymptomatic ones (42.9% vs 7.1%, P = 0.049). In all relatives, other diagnostic tests including electroencephalography, electromyography and head magnetic resonance imaging (MRI) for subclinical nervous system involvement and Kayser-Fleischer rings examination yielded normal results. In pre/asymptomatic siblings, genetic and biochemical studies may aid to initiate treatment prior to the development of permanent tissue damage. Our results indicate that abnormal EPs may signal unique pathological finding in some subjects. Importantly, these abnormalities occur earlier than Kayser-Fleischer rings and MRI lesions. In early stages of WD, EP recordings may, therefore, be used to help decide on treatment initiation and treatment efficacy evaluation. Moreover, EP recordings can readily be added to family screening studies.  相似文献   
96.
Abstract   Acute isolated neurological syndromes, such as optic neuropathy or transverse myelopathy, may cause diagnostic problems since they can be the first presentations of a number of diseases such as multiple sclerosis (MS) and collageneous tissue disorders. In the present study, particular systemic lupus erythematosus (SLE) and primary Sjogren syndrome (pSS) patients, who were followed up with the initial diagnosis of possible MS with no evidence of collagen tissue disorders for several years, are described. Five patients with the final diagnosis of SLE and five pSS patients are evaluated with their neurologic, systemic and radiologic findings. Over several years, all developed some systemic symptoms like arthritis, arthralgia, headache, dry mouth and eyes unexpected in MS. During the regular and close follow-up laboratory evaluations of vasculitic markers revealed positivity, leading to the final definite diagnosis of SLE or pSS. Patients with atypical neurological presentation of MS, a relapsing remitting clinical profile, or lack of response to the regular MS treatment should be evaluated for the presence of a connective tissue disease. Various laboratory tests, such as cerebrospinal fluid findings, autoantibodies profile, markers, cranial and spinal magnetic resonance imaging, can be helpful for the differential diagnosis. Lack of response to the regular multiple sclerosis treatment, even increasing rate of relapses can force the clinician for the differential diagnosis. In particular cases an accurate diagnosis can only be made after close follow-up.  相似文献   
97.
98.
The aim of this study was to assess the clinical and laboratory correlations of bone mineral density (BMD) measurements among a large population of patients on chronic peritoneal dialysis (PD). This cross-sectional, multicenter study was carried out in 292 PD patients with a mean age of 56 ± 16 years and mean duration of PD 3.1 ± 2.1 years. Altogether, 129 female and 163 male patients from 24 centers in Canada, Greece, and Turkey were included in the study. BMD findings, obtained by dual-energy X-ray absorptiometry (DEXA) and some other major clinical and laboratory indices of bone mineral deposition as well as uremic osteodystrophy were investigated. In the 292 patients included in the study, the mean lumbar spine T-score was −1.04 ± 1.68, the lumbar spine Z-score was −0.31 ± 1.68, the femoral neck T-score was −1.38 ± 1.39, and the femoral neck Z score was −0.66 ± 1.23. According to the WHO criteria based on lumbar spine T-scores, 19.2% of 292 patients were osteoporotic, 36.3% had osteopenia, and 44.4% had lumbar spine T-scores within the normal range. In the femoral neck area, the prevalence of osteoporosis was slightly higher (26%). The prevalence of osteoporosis was 23.3% in female patients and 16.6% in male patients with no statistically significant difference between the sexes. Agreements of lumbar spine and femoral neck T-scores for the diagnosis of osteoporosis were 66.7% and 27.3% and 83.3% for osteopenia and normal BMD values, respectively. Among the clinical and laboratory parameters we investigated in this study, the body mass index (BMI) (P < 0.001), daily urine output, and urea clearance time × dialysis time/volume (Kt/V) (P < 0.05) were statistically significantly positive and Ca × PO4 had a negative correlation (P < 0.05) with the lumbar spine T scores. Femoral neck T scores were also positively correlated with BMI, daily urine output, and KT/V; and they were negatively correlated with age. Intact parathyroid hormone levels did not correlate with any of the BMD parameters. Femoral neck Z scores were correlated with BMI (P < 0.001), and ionized calcium (P < 0.05) positively and negatively with age, total alkaline phosphatase (P < 0.05), and Ca × P (P < 0.01). The overall prevalence of fractures since the initiation of PD was 10%. Our results indicated that, considering their DEXA-based BMD values, 55% of chronic PD patients have subnormal bone mass—19% within the osteoporotic range and 36% within the osteopenic range. Our findings also indicate that low body weight is the most important risk factor for osteoporosis in chronic PD patients. An insufficient dialysis dose (expressed as KT/V) and older age may also be important risk factors for osteoporosis of PD patients.  相似文献   
99.
100.
Lidocaine with epinephrine is currently the most common local anesthetic agent used for impacted third molar surgery. The purpose of the present study was to define the adverse hemodynamic effects and plasma concentrations of lidocaine and epinephrine on 17 healthy patients during the impacted teeth operations. Arterial blood pressure (systolic blood pressure, diastolic blood pressure), heart rate, peripheral oxygen saturation range, and electrocardiography were measured by an automatic noninvasive pressure device and monitor. High-performance liquid chromatography was used to measure the changes of plasma concentrations of epinephrine and lidocaine from blood samples taken 5 different times during the operation. We concluded that lidocaine-epinephrine is effective local anesthetic and had no important adverse events in healthy patients during the third molar surgery.  相似文献   
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