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941.
Eleven sedentary male volunteers were assigned to either an exercise (E) group (n = 6; endurance exercise for 12 weeks) or a control (C) group (n = 5; no exercise). After training, E significantly increased (p less than 0.01) their VO2max (pretraining: 37.0 +/- 2.3; posttraining: 44.6 +/- 2.5), whereas C showed no significant change. Heart rate (HR), arterial blood pressure (BP) and forearm blood flow (FBF) were measured both pre- and posttraining at rest and during 2 levels of LBNP: -10 mm Hg and -40 mm Hg. Both C and E had similar decreases in systolic BP and similar increases in HR and diastolic BP during LBNP when comparing the pre- and posttraining periods. In both groups, FBF significantly decreased during -40 mm Hg of LBNP in the pretraining period. However, after training, E had a significantly attenuated (p less than 0.05) decrease in FBF at -40 mm Hg (pretraining: -45.0 +/- 3.7%; posttraining: -29.8 +/- 3.1%). In C, there was no difference in the response of FBF to -40 mm Hg of LBNP comparing pretraining and posttraining. These findings indicate that endurance exercise training decreases the forearm vasoconstrictor response to high levels of LBNP. 相似文献
942.
943.
Frances L. Watson Mary-Anne L. Pasteur David T. Healy Elizabeth A. Hughes 《Human psychopharmacology》1994,9(1):51-61
Four memory tests, each containing nine parallel forms, were developed and assessed for their suitability for use in psychopharmacological research. The tests measured verbal memory, face-name-occupation associate learning, spatial location memory and memory for visual designs. Twenty-seven healthy subjects completed a different form of each test on each of nine testing occasions. Test form administration order was rotated across subjects to permit the independent assessment of practice effects and test form equivalence. Performance on four of the test forms differed significantly from performance on other forms of the same test. Data from the remaining forms contained no significant test form differences and these were assumed to be equivalent. ANOVA indicated practicerelated changes in six of the seven measures examined. Four or five successive test sessions were required before performance stabilized. Initial ‘dips’ in performance observed in the verbal memory tests were attributed to proactive interference, whilst further performance improvements in spatial location performance that occurred in the last three days of the study may have been caused by the development of mnemonic strategies. Thus, patterns of change with practice varied across the four tests. The results underline the importance of documenting practice effects in relation to repeated memory assessment. 相似文献
944.
945.
Claire M Healy Anne-Marie Tobin Brian Kirby Stephen R Flint 《Oral surgery, oral medicine, oral pathology, oral radiology, and endodontics》2006,101(2):184-187
Dermatomyositis (DM) is an inflammatory disease of skeletal muscle with characteristic cutaneous features. Oral manifestations of DM have been very rarely described. This case describes a patient in whom the oral lesions were among the initial manifestations of DM. The lesions were very painful and the most distressing component of the disease in this patient. High dose systemic steroids were required to control the lesions. Investigations for an occult malignancy in this patient resulted in the identification of a non-Hodgkin's lymphoma in her right kidney. Commencement of chemotherapy rapidly resulted in complete resolution of her oral and skin lesions. 相似文献
946.
947.
知母中呋甾皂甙的研究 总被引:16,自引:2,他引:14
自知母 Anemarrhena asphodeloides Bge.根茎的乙醇提取物中,经硅胶柱层析和制备型HPLC分得四种呋甾皂甙。用化学反应和波谱(IR,FAB-MS,EI-MS,1HNMR,13CNMR,DEPT,一维多重接力CoSY,二维接力HOHAHA,1H-1H COSY,1H-13C COSY和NOE差谱)解析,确定其结构为知母皂贰B(anemarsaponinB,I),(25S)-26-O-β-D-吡喃葡萄糖基-5β-呋甾-20(22)-烯-3β,26-二醇-3-O-β-D-吡喃葡萄糖基(1→2)-β-D-吡喃哺葡萄糖甙(Ⅱ),(25S)-26-O-β-D-吡喃葡萄糖基-22-羟基-5β-呋甾-3β,26-二醉-3-O-β-D-吡喃葡萄糖基(1→2)-β-D-吡喃半乳糖甙(Ⅲ),(25S)-26-O-β-D-吡喃葡萄糖基-22-甲氧基-5β-呋甾-3β,26-二醇-3-O-β-D-吡喃葡萄糖基(1→2)-β-D-吡喃半乳糖甙(Ⅳ)。Ⅱ为一新的呋甾皂甙,命名为知母皂甙C;化合物Ⅳ为首次从知母中分离得到,命名为知母皂甙E。初步的药理实验显示,化合物1~Ⅳ均有一定的清除羟自由基的作用。 相似文献
948.
949.
950.
Rigauts HD; Selleslag DL; Van Eyken PL; Van Damme BJ; Fevery JM; Marchal GJ 《Radiology》1988,169(3):661-662
A 67-year-old patient was admitted with a 2-week history of epigastric discomfort that began after an episode of upper respiratory tract infection treated with erythromycin. Results of liver function tests were abnormal. Abdominal ultrasound (US) and computed tomography showed multiple, poorly demarcated irregular lesions in both hepatic lobes, suggestive of diffuse metastatic invasion. Histologic examination of the biopsy specimen revealed drug-induced hepatitis. Ten weeks after withdrawal of the erythromycin, US showed complete resolution of the hyperechogenic liver lesions. 相似文献