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981.
We developed a computerised test to evaluate unilateral spatial neglect (USN) using a touchscreen display, and estimated the spatial and temporal patterns of visual search in USN patients. The results between a viewer-centered USN patient and a stimulus-centered USN patient were compared. Two right-brain-damaged patients with USN, a patient without USN, and 16 healthy subjects performed a simple cancellation test, the circle test, a visuomotor search test, and a visual search test. According to the results of the circle test, one USN patient had stimulus-centered neglect and a one had viewer-centered neglect. The spatial and temporal patterns of these two USN patients were compared. The spatial and temporal patterns of cancellation were different in the stimulus-centered USN patient and the viewer-centered USN patient. The viewer-centered USN patient completed the simple cancellation task, but paused when transferring from the right side to the left side of the display. Unexpectedly, this patient did not exhibit rightward attention bias on the visuomotor and visual search tests, but the stimulus-centered USN patient did. The computer-based assessment system provided information on the dynamic visual search strategy of patients with USN. The spatial and temporal pattern of cancellation and visual search were different across the two patients with different subtypes of neglect.  相似文献   
982.
983.
Many retrospective studies have found that the functional outcome after a low anterior resection for rectal cancer is better with colonic J-pouch reconstruction than with conventional straight anastomosis. This advantage was demonstrated in prospective, randomized trials and meta-analyses. However, despite its increasing popularity there are several areas of controversy about the use of the colonic J-pouch reconstruction. These issues include anastomotic leaks, the part of the colon used for the pouch, the pouch size, causes of difficulty in evacuation, indications (the optimum level of anastomosis), appropriateness for the elderly, and long-term (2 years or more after surgery) functional outcome. All relevant articles identified from MEDLINE databases were reviewed. The incidence of anastomotic leaks is apparently reduced by colonic J-pouch reconstruction. A 5-cm colonic J-pouch using the sigmoid colon increases the reservoir function without compromising evacuation, and provides better functional outcome than straight anastomosis, even 2 years or more after surgery, in patients whose anastomosis is less than 8 cm from the anal verge. Patients with ultralow anastomoses, less than 4 cm from the verge, appear to benefit the most. At a time when the indications for abdominoperineal excision appear to be reduced for low rectal cancer, the demand for colonic J-pouch reconstruction (the best technique in pouch operations) is therefore likely to increase.  相似文献   
984.
985.
PURPOSE: Possible significance of sex hormone estrogen as an antitumor therapeutic arm toward esophageal squamous cell carcinoma (ESCC) cells has been suggested. The aim of the current study was to clarify the clinicopathologic significance of an immunohistochemical expression of estrogen receptors alpha and beta (ER alpha and ER beta) in ESCC. EXPERIMENTAL DESIGN: Expression of ER alpha and ER beta were examined using an immunohistochemical methods in 73 paraffin-embedded sections collected from patients with ESCC who had been subjected to esophageal resection and digestive reconstruction without any preoperative induction therapy. RESULTS: Forty-seven (64.4%) ESCCs had a positive cytoplasmic expression of ER alpha and 21 (28.8%) ESCCs had a positive nuclear expression of ER beta. Univariate analysis showed that both positive ER alpha expression (P=0.0001) and negative ER beta expression (P=0.026) were unfavorable prognostic indicators in ESCC. Moreover, multivariate analysis showed that ER alpha-positive/ER beta-negative expression (P=0.003) and progression of tumor stage (P=0.014) were found to be independent unfavorable prognostic indicators in ESCCs. CONCLUSIONS: Immunohistochemical expression of ER alpha and ER beta were found to be observed in ESCC. Positive expression of ER alpha in addition to negative expression of ER beta proved to be an unfavorable independent prognostic indicator in ESCC.  相似文献   
986.
Infection with Helicobacter pylori is linked to inflammation and is the main cause of peptic ulcer, gastritis, and gastric malignancies. To examine associations between gastric cancer risk and the erythrocyte composition of docosahexaenoic acid (DHA), a fatty acid with anti-inflammatory and apoptosis-inducing effects, here we conducted a case-control study of 179 incident gastric cancer cases and 357 noncancer controls (matched by age, sex, and season of sample collection). Dietary information and blood samples were collected from all subjects, and erythrocyte fatty acid levels were measured using accelerated solvent extraction and gas-liquid chromatography. Gastric cancer risk did not seem to be directly associated with dietary intake of fish and n-3 highly unsaturated fatty acids (HUFAs), such as DHA, derived from fish. However, risk was inversely associated with erythrocyte compositions of n-3 HUFAs [the highest to the lowest tertile, odds ratio (OR), 0.39; 95% confidence interval (95% CI), 0.23-0.68; P(trend)<0.005] and DHA (OR, 0.47; 95% CI, 0.28-0.79; P(trend)<0.01). Particularly strong associations were noted for well-differentiated type lesions and n-3 HUFAs (OR, 0.10; 95% CI, 0.03-0.35; P(trend)=0.0005) as well as DHA (OR, 0.20; 95% CI, 0.07-0.58; P(trend)<0.01) values. In conclusion, the erythrocyte composition of DHA was found to be negatively linked to risk of gastric cancer, especially of well-differentiated adenocarcinoma. Further studies are needed to investigate mechanisms of action of DHA relevant to antitumor effects in the stomach.  相似文献   
987.
Accumulating evidence suggests that the glycine modulatory site on the NMDA receptor could be potential therapeutic target for cognitive deficits in schizophrenia. The present study was undertaken to examine the effects of the glycine transporter-1 (GlyT-1) inhibitor, (R)-(N-[3-(4'-fluorophenyl)-3-(4'-phenylphenoxy)propyl])sarcosine (NFPS), on cognitive deficits in mice after repeated administration of the NMDA receptor antagonist phencyclidine (PCP). PCP (10 mg/kg/day for 10 days)-induced cognitive deficits were significantly improved by subsequent subchronic (2-week) administration of NFPS (1.0 and 3.0 mg/kg/day) or D-serine (600 mg/kg/day). However, PCP-induced cognitive deficits were not improved by a single administration of NFPS (3.0 mg/kg). Furthermore, Western blot analysis revealed that levels of GlyT-1 in the hippocampus, but not frontal cortex, of the PCP (10 mg/kg/day for 10 days)-treated mice were significantly higher than those of saline-treated mice. An in vivo microdialysis study revealed that repeated PCP administration significantly decreased the extracellular levels of glycine in the hippocampus, but not frontal cortex, of mice. These findings suggest that repeated PCP administration increased the density of GlyT-1 in the hippocampus of mouse brain, and that the GlyT-1 inhibitor NFPS could ameliorate cognitive deficits in mice after repeated administration of PCP.  相似文献   
988.
The aim of this study was to investigate the effect of molecular weight on the topical migration and systemic absorption of drugs, sodium salicylate (SA), calcein sodium (CAL) and FITC-dextrans (FD-4, FD-10, FD-20 and FD-40), after intracutaneous (i.c.) injection. The apparent diffusion coefficients in the skin (D(s)) of SA, CAL and FD-4 after i.c. injection were almost the same and slightly less than 1x10(-4)cm(2)/min. The D(s) value drastically decreased with molecular weight more than 10kDa. The plasma concentration-time curve after i.c. injection was predicted by the convolution method. The ratio of AUC (observed/predicted) was approximately unity for SA, CAL and FD-4 although the systemic absorption of only FD-4 was delayed. In contrast, the AUC ratios of FD-10, FD-20 and FD-40 were about 0.5, 0.2 and 0.06, respectively, and obviously decreased with the molecular weight. The elimination of FD-10, FD-20 and FD-40 from the skin was slow and the drugs tended to remain in the muscle. These results indicated the importance of diffusion in the skin and permeability through the blood vessels for local migration and systemic absorption of drugs after penetration into viable skin.  相似文献   
989.
[目的]了解城市交通区不同地区和不同时间内颗粒物中多环芳烃的分布特征。[方法]对某城市某交通区不同地点颗粒物和多环芳烃的含量分别进行了监测,同时在1个地点进行了连续24h监测。[结果]不同地段颗粒物中多环芳烃的含量不同,总体趋势是:高架下大气中颗粒物多环芳烃的污染比高架上严重;城区比郊区污染严重;隧道内比隧道外污染严重。同时,同一地点颗粒物及其中多环芳烃连续24h的监测结果表明,在24h内,大气中颗粒物及其中的多环芳烃含量有规律的波动,在清晨、下午出现两个高峰。研究还发现在颗粒物和其中多环芳烃之间存在明显的相关性,相关系数为0.231,并得到了回归模型;对不同粒径的成分分析结果表明,PM2.5占PM10的30%~50%,是主要的多环芳烃携带颗粒物。[结论]交通因素以及周围环境因素是导致大气中颗粒物多环芳烃污染浓度改变的主要因素之一;PM2.5是主要的多环芳烃的携带者。  相似文献   
990.
Summary In an 18-year-old male with Eisenmenger syndrome cyanosis and erythrocytosis were increasing. The erythrocytosis diminished following oral bunazosin and phlebotomy was not needed during the treatment. When bunazosin was stopped, the erythrocytosis increased, but when it was resumed, the erythrocytosis and general fatigue diminished.  相似文献   
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