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101.
低剂量甲基汞在小鼠体内分布及其对细胞周期进程的影响 总被引:3,自引:0,他引:3
连续90天饮用含甲基汞浓度为1/1000LD50、1/100LD50、1/50LD50和1/10LD50的自来水的雄性昆明小鼠,各脏器中总汞含量均高于对照组(P<0.05~0.005),并且随着染毒剂量增加,脏器中总汞含量也随之增高。同时采用FACScan流式细胞仪和“CellFIT”软件分析脾细胞周期进程,发现除1/1000LD50剂量组外,其余各剂量组从Go/G1时相进入S时相的脾细胞百分数均明显高于对照组(P<0.05),与染毒剂量呈明显正相关。表明连续经口摄入低剂量甲基汞小鼠脾细胞周期进程加快,细胞DNA复制增强。 相似文献
102.
目的 探讨大剂量甲基强的松龙冲击疗法治疗外伤性视神经病变的疗效。方法 2 0例 (2 0只眼 )外伤性视神经病变患者为治疗组 ,应用大剂量甲基强的松龙冲击治疗 ,另 2 0例 (2 0只眼 )外伤性视神经病变患者为对照组 ,使用常规剂量的地塞米松治疗。两组均同时使用高渗剂、血管扩张剂、神经营养剂及 B族维生素治疗 ,对两组病例药物治疗的结果进行总结分析。结果 治疗组经治疗后视力开始恢复的时间早于对照组 ,治疗组的总有效率为 80 % ,对照组的总有效率为 6 0 % ,治疗组的疗效优于对照组 ,且治疗越早疗效越好。两组比较具有显著的统计学差异 (P <0 .0 5 )。结论 大剂量甲基强的松龙冲击疗法治疗外伤性视神经病变疗效显著 ,治疗方便 ,是较理想的治疗方法 相似文献
103.
Philippe Rochat 《Experimental brain research. Experimentelle Hirnforschung. Expérimentation cérébrale》1998,123(1-2):102-109
By 2–3 months, infants engage in exploration of their own body as it moves and acts in the environment. They babble and touch
their own body, attracted and actively involved in investigating the rich intermodal redundancies, temporal contingencies,
and spatial congruence of self-perception. Recent research is presented, which investigats the spatial and temporal determinants
of self-perception and action infancy. This research shows that, in the course of the first weeks of life, infants develop
an ability to detect intermodal invariants and regularities in their sensorimotor experience, which specify themselves as
separate entities agent in the environment. Recent observations on the detection of intermodal invariants regarding self-produced
leg movements and auditory feedback of sucking by young infants are reported. These observations demonstrate that, early in
development and long before mirror self-recognition, infants develop a perceptual ability to specify themselves. It is tentatively
proposed that young infants’ propensity to engage in self-perception and systematic exploration of the perceptual consequences
of their own action plays an important role in the intermodal calibration of the body and is probably at the origin of an
early sense of self: the ecological self. 相似文献
104.
S. M. Mirbod Hideyo Yoshida Marjan Jamali Kazuhito Masamura Ryoichi Inaba Hirotoshi Iwata 《International archives of occupational and environmental health》1997,70(1):22-28
The aims of this study were (1) to evaluate subjective symptoms in the hand-arm system of all traffic police motorcyclists
of a city located in the central part of Japan and (2) to assess their hand-arm vibration exposure associated with traffic
police motorcycle riding. The study population consisted of 119 motorcycling traffic policemen and 49 male controls. By means
of a questionnaire, information on the occupational history and the presence of subjective symptoms in the hand-arm system
of all subjects was obtained. Vibration was measured on the handlebars of the representative motorcycles and on the hands
of the riders. The 4- and 8-h energy-equivalent frequency-weighted acceleration as well as the lifetime vibration dose were
calculated for all police motorcyclists. The prevalence of finger blanching in the traffic police motorcyclists was 4.2%,
but none of the controls had this symptom. The rates of finger numbness (19.3%), finger stiffness (16.0%), shoulder pain (13.4%),
and shoulder stiffness (45.4%) were significantly higher among police motorcyclists as compared with controls. The root-mean-square
(rms) frequency-weighted acceleration on the handlebars of police motorcycles was in the range of 2.2–4.9 m/s2 rms. The computed 4- and 8-h energy-equivalent frequency-weighted acceleration values were 2.8– 4.5 and 2.0 –3.2 m/s2 rms, respectively. A pattern of increasing percentage prevalence with increasing cumulative vibration dose was noticed. The
subjects with a lifetime vibration dose of more than 20.1 m2 h 3 s-4 (ln scale) showed significantly higher prevalence rates for symptoms in the fingers and shoulders as compared with the control
group. As occupational vibration exposure of traffic police motorcyclists might be considered a risk factor for the development
of symptoms in the hand-arm system of the riders, its evaluation and control is needed for prevention methodology evolution.
Received: 15 April 1996/Accepted: 8 November 1996 相似文献
105.
Associations between body morphology and bone mineral density in premenopausal women 总被引:1,自引:0,他引:1
To investigate whether body morphology, obesity and its long time evolution were associated with lumbar and femoral bone mineral density (BMD) in premenopausal women of the same age. Design: Cross-sectional study. Subjects: 72 healthy premenopausal women born in 1950 (42 years) with a regular physical activity. Measurements: BMD measured by dual-X-ray absorptiometry (DEXA) at lumbar spine and proximal femur; body weight, body mass index (BMI), BMI at 20 years (BMI-20), increase in BMI since age of 20 (BMI->20), body circumferences (breast, waist, hip) and their ratios (WHR, BHR, WBR), smoking and alcohol intake. Results: Lumbar spine BMD did not correlate with any anthropometric measurement. Femoral BMDs correlated positively with weight, BMI, BMI-20, breast, waist, WHR and BHR. The BMI-20 explained the 5% and the current BMI the 13% of variance of total femur BMD. After adjustment for weight or BMI, breast circumference and BHR remained significantly correlated with all femoral BMDs sites except neck. Weight was the best predictor for neck BMD (R2 = 0.08; p < 0.02), and BHR for Ward's triangle (R2 = 0.12; p < 0.01) and trochanter (R2 = 0.10; p < 0.001). Alcohol intake, cigarette smoking, and age of menarche were not related to BMDs. Conclusion: In premenopausal women of the same age, lumbar spine BMD was not associated with any anthropometric measurement. Greater BHR and its long time of evolution may be determinants of greater femoral BMD (trabecular), whereas body weight may be determinant of femoral neck BMD (cortical). Further studies are needed to determine whether large breast to hip ratio may be considered as a protective factor for femoral osteoporosis. 相似文献
106.
Twenty-five persons with diabetes (aged 55–83 years) who were living independently in the community, and 40 age- and sex-matched non-diabetic controls were assessed for tactile sensitivity, vibration sense, proprioception, quadriceps strength and body sway. In both men and women, those with diabetes performed significantly worse in tests of body sway on firm and compliant surfaces compared with the control subjects after controlling for weight and body mass index. The female diabetic subjects also performed significantly worse in tests of peripheral sensation and strength compared with controls. Age-related declines in sensori-motor function were greater in the diabetic group (r = 0.55–0.75) than in the controls (r < 0.44), while within the diabetic group, duration of diabetes and vibration sense were significantly correlated with sway on a compliant (foam rubber) surface with the eyes open (partial r = 0.52, p < 0.01 and r = 0.55, p < 0.01, respectively). The study findings provide evidence that older people with diabetes have problems with stability and related sensori-motor factors which may place them at increased risk of falls. 相似文献
107.
王佑三 《山东中医药大学学报》1990,(4)
《明天的医学向何处去》一文是王佑三同志应中国中医研究院、中西医结合研究会1990~2010年中医药研究的重大进展与突破预测研究课题组和中国人体科学学会之约所撰。本报征得作者同意稍加删节后发表,期望引起对“明天的医学”的关注。 相似文献
108.
Peripheral and central injections of recombinant human interleukin-1β (IL-1β) have been shown to decrease social exploration and to induce body weight loss in rats. To characterize the receptor mechanisms of these effects, we used as a tool a specific antagonist of the receptors of IL-1, IL-1ra. Intraperitoneal (i.p.) administration of IL-1ra (8 mg/kg) blocked the effect of i.p. injection of IL-1β (4 μg/rat) on social behaviour but not on body weight. Central administration of IL-1ra (60 μg/rat, i.c.v.) abrogated the effects of centrally administered IL-1β (30 ngn/rat, i.c.v.) on both social behaviour and body weight. Central injection of IL-1ra (4 μg/rat, i.c.v.) also attenuated the effects of i.p. administered IL-1β (4 μg/rat) on social behaviour but not on body weight. These results suggest that the effects of IL-1β on social behavior are mediated centrally and that its effect on the loss of body weight involves different receptor mechanisms. 相似文献
109.
目的 为了解中日儿童及成人的步行和体成分及其相互关系.方法 以中国上海市和日本琦玉县的小学生和成人为对象,采用西铁城 TW02-001电子式步数计测定步行量,FUTREX-5000A体成分测定仪测量体脂百分比.结果 1.中国男女小学生的平均每日步行量分别为12426步和10387步,低于日本小学生(男15 340步,女11 617步),体脂百分比中国男女生分别为21.2%和15.8%,高于日本(男18.9%,女13.1%).中国男女成人的平均每日步行量分别为9826步和8748步,高于日本成人(男:8411步,女7599步);体脂百分比分别为17.5%(男)和25.8%(女),而日本男性为19.8%,女性为26.0%.2.不同活动水平的小学生和成人,其血压和体成分均有差异,步行量高者的血压和体脂百分比都较低.本研究还计算出以肱三头肌皮脂厚度以(X)推测儿童体脂百分比(Y)的回归方程为:Y=10.6646+0.5856X.结论 作为日常生活的步行可促进肥胖发生率的降低. 相似文献
110.
A breathing lung phantom for 81mKr lung ventilation studies its use in dosimetry and quality control
J. A. J. Camps C. Zuur J. A. K. Blokland J. J. Broerse E. K. J. Pauwels 《European journal of nuclear medicine and molecular imaging》1988,14(11):529-532
The construction of a breathing lung phantom that can be used to measure the amount of radioactive gas in the lungs as well as to determine the absorbed dose is described. For a lung ventilation study that consists of 6 views of 300 kents each, an effective dose equivalent of 50 Sv was calculated. The phantom is also suitable for comparison of different generator systems. 相似文献