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101.
Bright light treatment is the most potent melatonin suppressor and circadian phase shifter and is a safe nonpharmacologic antidepressant for seasonal depression. In addition, bright light treatment may restore performance in conditions of sleep debt and misalignment between peak performance and the athletic event. This article discusses the therapeutic use of bright light treatment, its side effects, and mechanisms of action. 相似文献
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104.
Sixteen young (25±2.6 years) and 16 older individuals (69±4.4 years) walked normally then terminated walking rapidly. A visual stopping stimulus was presented 10 ms following ground contact (short delay) and in another condition, at 450 ms prior to toe-off (long delay). Stimulus probability was either high (80% of trials) or low (10%). The younger group stopped faster (463 vs. 574 ms) despite also walking faster (1.29 vs. 1.17 m s−1). Longer delay decreased one-step responses but older participants used significantly more (slower) two-step stopping, which increased stopping time and distance. The additional step may have been pre-planned to maintain medial–lateral stability. 相似文献
105.
Cahlon O Klepps S Cleeman E Flatow E Gilbert M 《Clinical orthopaedics and related research》2004,(423):106-111
Bleeding into large joints is the most common orthopaedic manifestation of hemophilia. Involvement of the shoulder rarely is reported, lending to its relative neglect in the orthopaedic literature. Through retrospective chart and radiographic reviews, the incidence and progression of radiographic and clinical changes that occur in the shoulder of patients with hemophilia is described. We retrospectively reviewed 822 patient charts and found 93 patients with symptomatic shoulders. Seventy-nine of these 93 patients were rated according to Pettersson's scoring method. The clinical charts were reviewed for the presence of shoulder symptoms and dysfunction. A spectrum of radiographic changes was seen beginning with mild subchondral irregularity and greater tuberosity cyst formation progressing to joint space narrowing, osteophyte formation, marginal erosion, and deformity. Of the 54 patients for whom an adequate shoulder history was available, the severity of symptoms correlated with the Pettersson score. The current study is the largest to date examining the type and progression of radiographic changes caused by hemophilic shoulder arthropathy. We observed a consistent pattern of radiographic changes, the severity of which correlated directly with shoulder symptoms. 相似文献
106.
Kan P Gottfried O Blumenthal DT Townsend JJ Drozd-Borysiuk E Brothman AR Jensen RL 《Journal of neurosurgery》2004,100(4):700-705
Multiple metastatic brain tumors and multifocal primary brain tumors of a single histological type are well described in the literature. The concurrent presence of multiple primary brain tumors with different histological characteristics, however, is very rare. The authors describe the first known case in which an oligodendroglioma and a juvenile pilocytic astrocytoma (JPA) presented as synchronous primary brain tumors in the same patient. This 43-year-old man presented with a 2-month history of progressive headaches, nausea, and vomiting. Magnetic resonance imaging demonstrated an enhancing heterogeneous right medial cerebellar lesion and a larger calcified, nonenhancing, heterogeneous right frontal lesion with surrounding edema and a mass effect. The results of a metastatic workup were unremarkable. The patient underwent an initial right frontotemporal craniotomy and a subsequent suboccipital craniectomy 2 years later for resection of the posterior fossa lesion. Histological examination revealed the frontal and cerebellar lesions to be an oligodendroglioma and JPA, respectively. A molecular analysis detected a deletion of chromosome 1p36 in the oligodendroglioma, but not in the JPA. After the initial operation, the patient received follow-up care for his oligodendroglioma, but eventually required temozolomide for tumor progression. His condition remains stable both neurologically and according to imaging studies. The authors describe the first known case in which a low-grade oligodendroglioma and a JPA presented as synchronous primary brain tumors. They review the literature on multiple primary brain tumors with different histological characteristics and discuss potential mechanisms for the development of these lesions. 相似文献
107.
Liu JK Tenner MS Gottfried ON Stevens EA Rosenow JM Madan N MacDonald JD Kestle JR Couldwell WT 《Journal of neurosurgery》2004,100(3):414-421
OBJECT: Cerebral vasospasm that is caused by aneurysmal subarachnoid hemorrhage and that is refractory to maximal medical management can be treated with selective intraarterial papaverine infusions. The effects of single papaverine treatments on cerebral circulation time are well known. The purpose of this study was to assess the efficacy of multiple, repeated papaverine infusions on the cerebral circulation time in patients with recurrent vasospasm. METHODS: A retrospective study was conducted in 17 patients who received multiple intraarterial papaverine infusions in 91 carotid artery (CA) territories for the treatment of cerebral vasospasm. Cerebral circulation times were measured from the first angiographic image, in which peak contrast was seen above the supraclinoid internal CA, to the peak filling of cortical veins. Glasgow Outcome Scale (GOS) scores assessed 12 months after discharge were reviewed. Cerebral circulation times in 16 CA territories were measured in a control group of 11 patients. Seventeen patients received a total of 91 papaverine treatments. Prolonged cerebral circulation times improved after 90 (99%) of 91 papaverine treatments. The prepapaverine mean cerebral circulation time was 6.54 seconds (range 3.35-27 seconds) and the immediate postpapaverine mean cerebral circulation time was 4.19 seconds (range 2.1-12.6 seconds), an overall mean decrease of 2.35 seconds (36%, p < 0.001). Recurrent vasospasm reflected by prolonged cerebral circulation times continued to improve with subsequent papaverine infusions. Repeated infusions were just as successful quantitatively as the primary treatment (mean change 2.06 seconds). The mean cerebral circulation time in the control group was 5.21 seconds (range 4-6.8 seconds). In five patients a dramatic reversal of low-attenuation changes was detected on computerized tomography scans. The mean GOS score at 12 months after discharge was 3.4. CONCLUSIONS: The preliminary results indicate that multiple intraarterial papaverine treatments consistently improve cerebral circulation times, even with repeated infusions in cases of recurrent vasospasm. 相似文献
108.
Duman M Irken G Oren H Uçar C Atabay B Yilmaz S Yüksel F Ozkan H 《Biology of the neonate》2003,84(3):206-213
In this study, we determined the plasma TGF-beta1 levels in healthy and thrombocytopenic and nonthrombocytopenic neonates who had perinatal risk factors and examined the association between plasma TGF-beta1 levels and platelet counts in these newborns to investigate the role of TGF-beta1 in the pathogenesis of neonatal thrombocytopenia. Three groups were defined in this prospective study: group 1, thrombocytopenic neonates (n=22) who had perinatal risk factors; group 2, nonthrombocytopenic neonates who had similar perinatal risk factors for thrombocytopenia (n=20); group 3, healthy and nonthrombocytopenic neonates without any risk factors (n=20). Plasma TGF-beta1 levels were measured with ELISA. Plasma TGF-beta1 levels of the thrombocytopenic neonates were significantly lower than those of healthy nonthrombocytopenic neonates but did not differ significantly from nonthrombocytopenic neonates who had similar perinatal risk factors for thrombocytopenia. There was a significant positive correlation between plasma TGF-beta1 levels and platelet counts. Further studies are needed to determine the cause of low plasma TGF-beta1 levels in thrombocytopenic neonates and to investigate the role of plasma TGF-beta1 levels in the pathogenesis of neonatal thrombocytopenia. 相似文献
109.
Irken G Oren H Undar B Duman M Gülen H Uçar C Sanli N 《The Turkish journal of pediatrics》2002,44(1):21-24
Turkey is located in a geographic area of the world where thalassemia syndromes and abnormal hemoglobins are common. In this study we aimed to evaluate the thalassemia syndromes and abnormal hemoglobins in patients from the Aegean region of Turkey. Among the patients admitted to our Pediatric Hematology or Hematology Clinic between January 1997-September 1999, hemoglobin electrophoresis of 3,228 cases investigated for anemia was done using high performance liquid chromatography. Beta thalassemia trait was diagnosed in 21.1%, beta thalassemia major in 0.2%, S-beta thalassemia in 0.37%, Hb D in 0.37%, Hb S trait in 0.32%, Hb E in 0.18%, Hb O-Arab in 0.12%, Hb G-Copenhagen in 0.09%, Hb D-Iran in 0.06%, Hb Lepore in 0.06%, Hb Hasharon in 0.03%. Our results demonstrate that people in the Aegean region of Turkey have a wide spectrum of thalassemia syndromes and abnormal hemoglobins. 相似文献
110.
The objective of this prospective case-control study was to identify and quantify demographic and clinical risk factors for venous ulcer disease, with special emphasis on heredity and physical activity. Patients presenting to a participating vascular surgery department between January and December 1997 with a first open venous ulcer served as cases. Controls were sampled among patients with subacute conditions such as skin problems, back pain, cold, headache/migraine, sore throat, and mild ear infections and were matched on referral physician, age (+/-5 years), and gender. Subjects were eligible if they were 18 years or older and were excluded if they had nonpalpable pedal pulse or any chronic active diseases such as cancer or AIDS. Cases' and controls' statuses were ascertained by the participating physicians. Data on risk factors were collected with an interviewer-administered questionnaire and were self-reported by patients. The mean age of participants was 61 years for cases (n = 102) and 59 years for controls (n = 200). Family history of maternal venous insufficiency (odds ratio (OR) = 6.8, 95% confidence interval (CI) = [1.9, 24.3]95%), vigorous exercise (OR = 8.9, CI = [1.1, 72.0]95%), and history of deep vein thrombosis (DVT) (OR = 17.6, CI = [2.9, 106.8]95%) were found to be significant predictors of venous ulcers in matched multivariate logistic regression analysis; number of pregnancies was also a significant risk factor in women (OR = 1.2, Cl = [1.0, 1.5]95%). Our study suggests that knowledge of family history of venous insufficiency and monitoring of physical activity will lead to ulcer prevention. Although physical activity is recommended for patients with venous insufficiency, vigorous exercise increases the likelihood of ulcerations. 相似文献