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Amino acid transport system L has been proposed to be one of the major nutrient transport systems at the blood-brain barrier. Using immunohistochemical analyses, a system L transporter LAT1 was shown to be expressed in the brain capillary endothelial cells in rats. Because LAT1 was coexpressed with 4F2 heavy chain which brings LAT1 to the plasma membrane, LAT1 is proposed to be functional in the plasma membrane of brain capillary endothelial cells. Both LAT1 and 4F2hc immunoreactivities were detected in a double line appearance surrounding endothelial cell nuclei, suggesting both proteins are present in the luminal and abluminal membranes. LAT1 is, thus, a blood-brain barrier system L transporter responsible for the permeation of aromatic or branched-chain amino acids and amino acid-related drugs such as L-DOPA.  相似文献   
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INTRODUCTION: Few studies have reported the response of high-molecular-weight (HMW) adiponectin to acute aerobic exercise. PURPOSE: The purpose of this study was to investigate the influence of acute aerobic exercise on HMW adiponectin in healthy men. METHODS: Eight healthy men (age, 24.9 +/- 1.8 yr; BMI, 21.9 +/- 0.5 kg x m) participated in this study. They performed two trials. Trial 1 [exercise trial (EX)] consisted of 60-min stationary cycle exercise (50% peak oxygen uptake) followed by 30-min rest. Trial 2 [control trial (CON)] was 90-min rest. Blood samples were drawn to assess hormones (catecholamine and insulin), metabolites (free fatty acid [FFA], glycerol, and glucose), and total and HMW adiponectin concentration. RESULTS: There were significant trial x group interactions in serum FFA and glycerol concentrations (P < 0.05). Serum FFA and glycerol concentrations were higher in EX than in CON (P < 0.05). There were significant trial x group interactions in plasma insulin and glucose concentration (P < 0.05). Plasma insulin and glucose concentrations were lower in EX than in CON (P < 0.05). Total adiponectin, HMW adiponectin concentration, and the ratio of HMW to total adiponectin concentration, however, were unchanged during aerobic exercise and postexercise. Also, those changes did not differ between EX and CON. CONCLUSION: Our results indicate that total adiponectin and HMW adiponectin concentrations are not regulated by the change of hormones or metabolites during acute moderate-intensity aerobic exercise and postexercise in healthy young men.  相似文献   
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Purpose: We examined the feasibility and effectiveness of bronchial arterial infusion (BAI) as induction chemotherapy before surgery for locally advanced non-small cell lung cancer (NSCLC). Methods: Eighteen patients with locally advanced NSCLC were given BAI consisting of cis-diamminedichloroplatinum (CDDP) (50–100 mg/m2) as induction chemotherapy before surgery (induction BAI). Six patients with clinical stage IIIA cancer had bulky N2 metastatic lymph nodes, and 12 patients with clinical stage IIIB cancer had T4 disease. Results: Of the 18 patients, 12 (67%) showed a partial response to the BAI therapy. Standard pulmonary resection was performed in 5 patients, pulmonary resection with the combined resection of adjacent organs was performed in 10 patients, and pulmonary resection with carinal resection and reconstruction was performed in 3 patients. Complete resection was possible in 14 patients (78%). There were no serious BAI therapy-related complications or postoperative deaths. The 5-year survival rate of the 18 patients was 35.7% and the median survival time (MST) was 19.4 months. Survival was better when complete resection was achieved after the induction BAI, especially in patients with stage IIIB (T4) disease. Conclusion: Based on our preliminary findings, BAI with CDDP as induction chemotherapy is feasible and may be an effective therapeutic modality for locally advanced NSCLC. Received: July 26, 2001 / Accepted: March 5, 2002  相似文献   
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PURPOSE: The incidence of testicular cancer is rare. However, it is a significant cancer in that it develops not only in old age but also in children and younger age. We investigated the epidemiological characteristics of testicular cancer in Japan, in order to elucidate its features and problems. PATIENTS AND METHODS: We surveyed hospitals and clinics in and around Gunma prefecture that treated patients with urologic diseases and reviewed the pathology records from 1985 to 1994, and calculated the annual age-adjusted incidence rates of testicular cancer. Incidence rates in Japan were taken from the estimates made by 'The Research Group for Population-based Cancer Registration in Japan'. The annual number of deaths, annual age-adjusted death rates from 1947 and 1998, the age-specific death rates and decrease rate of them, and the prefectural standardized mortality ratio (SMR) from 1973 and 1998 was calculated from the data reported by Ohno et al. and statistical tables kept in 'Statistics and Information Department, Minister's Secretariat, Ministry of Health and Welfare'. RESULTS: In Gunma Prefecture, the annual age-adjusted incidence rates tended to increase. In estimated data of national survey, it slightly increased from 1975-79 to 1980-84, and remained stable thereafter. The annual number of deaths and age-adjusted death rates tended to decrease from around 1980. The peak of age-specific death rates was seen in infants, age 20 to 40 and old age. The decrease in the age-specific death rate was prominent for age under 20 and old age, but not significant for age 25 to 34. Prefectures in which SMR was high (> or = 120) were distributed all over Japan, but prefectures in which SMR was low (< or = 80) were concentrated in western Japan. CONCLUSIONS: The annual number of deaths and age-adjusted death rates began to decrease from around 1980, which coincided with the time the clinical trial of cis-platinum began. More than 100 deaths of testicular cancer are reported even now, early diagnosis, early treatment, and improvement of treatment strategy to far-advanced cases are necessary.  相似文献   
37.
Granular cell tumors are uncommon but typically histologically benign neoplasms that occasionally behave as malignant tumors. Differentiation of benign granular cell tumors from malignant counterparts with radiographic and/or histologic analysis is crucial for physicians. We retrospectively studied five cases of intramuscular granular cell tumors arising in the lower extremities. All tumors had been histologically diagnosed as benign and were resected with a wide surgical margin. The minimum followup was 1 year (mean, 45 months; range, 12–119 months) after surgery. Four patients had no local recurrence or distant metastasis (at a minimum of 18 months followup), whereas one patient with lymph node metastasis had a recurrence and distant metastasis 3 months after surgery resulting in death. Intramuscular granular cell tumors can be diagnosed based on their characteristic MRI features, such as peripheral high intensity on T2-weighed images, and histologic evaluation. The histologic criteria described by Fanburg-Smith et al. can differentiate malignant granular cell tumors from benign tumors. A wide resection seems suitable for most granular cell tumors in the extremities.  相似文献   
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OBJECTIVE: The Karolinska sleepiness scale (KSS) is frequently used for evaluating subjective sleepiness. The main aim of the present study was to investigate the validity and reliability of the KSS with electroencephalographic, behavioral and other subjective indicators of sleepiness. METHODS: Participants were 16 healthy females aged 33-43 (38.1+/-2.68) years. The experiment involved 8 measurement sessions per day for 3 consecutive days. Each session contained the psychomotor vigilance task (PVT), the Karolinska drowsiness test (KDT-EEG alpha & theta power), the alpha attenuation test (AAT-alpha power ratio open/closed eyes) and the KSS. RESULTS: Median reaction time, number of lapses, alpha and theta power density and the alpha attenuation coefficients (AAC) showed highly significant increase with increasing KSS. The same variables were also significantly correlated with KSS, with a mean value for lapses (r=0.56). CONCLUSIONS: The KSS was closely related to EEG and behavioral variables, indicating a high validity in measuring sleepiness. SIGNIFICANCE: KSS ratings may be a useful proxy for EEG or behavioral indicators of sleepiness.  相似文献   
40.
OBJECTIVE: To compare site-dependent changes across the carpal tunnel in axonal persistent Na+ conductances in motor and sensory axons. Positive sensory symptoms are prominent features in carpal tunnel syndrome, and a persistent Na+ current is a major determinant of axonal excitability. METHODS: The technique of latent addition was used to estimate persistent Na+ currents in median motor and sensory axons at the wrist and palm of 10 normal subjects. Brief hyperpolarizing conditioning current pulses were delivered, and threshold change at the conditioning-test interval of 0.2 ms was measured as an indicator of persistent Na+ currents. RESULTS: Threshold changes at 0.2 ms were greater in sensory than in motor axons at both the wrist and palm. In motor axons, the threshold changes were significantly smaller at the palm (mean, 4.9%) than at the wrist (10.0%). By contrast, the threshold changes were similar at the two sites of sensory axons (12.6 and 13.1%). The passive membrane time constant was similar for motor and sensory axons at the palm and wrist. CONCLUSIONS: Nodal persistent Na+ conductances have substantial site-dependent changes decreasing distally across the carpal tunnel in median motor axons, but not in sensory axons. SIGNIFICANCE: Whereas sensory axons generally have higher excitability than motor axons, the sensory-motor differences become more prominent across, and possibly at the carpal tunnel than the nerve trunk, and it is suggested that this contributes to the predominance of positive sensory symptoms in carpal tunnel syndrome.  相似文献   
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