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91.
上海市婴幼儿血铅水平与体格发育的关系   总被引:24,自引:2,他引:22  
Yan C  Shen X  Zhang Y  Wu S  He J  Zhou J  Zhang Y  Ao L  Wu S  Guo D 《中华预防医学杂志》1999,33(5):269-271
目的探讨低水平铅暴露对儿童体格发育的影响。方法在上海市5个区县30所托幼机构,对1969名儿童进行了血铅水平的流行病学调查和体格发育等指标测量,并根据儿童身高、体重、头围和胸围计算其Z标准分,然后与血铅水平进行相关分析和逐步回归分析。结果上海市儿童血铅水平几何均数为0.400μmol/L,≥0.483μmol/L的比例为37.8%,血铅水平的几何均数与儿童身高、体重及头围的Z标准分呈显著的负相关。结论低水平铅暴露对上海市婴幼儿的体格发育可能具有不利影响。  相似文献   
92.
体质指数与非吸烟女性肺癌关系的病例对照研究   总被引:16,自引:0,他引:16  
研究分析体质指数与非吸烟女性肺癌的关系。方法1992年2月至1993年12月,上海地区开展的一项大规模女性肺癌人群基础上的病例对照研究,共调查了非吸烟女性肺癌病例504例及人群对照601例。  相似文献   
93.
杨文友 《肉品卫生》1999,(12):3-4,19
应用常规体温检测方法,对2401头经基层食品经营站检疫合格的商品猪,经汽车集中运输至肉联厂后进行体温检测。结果:商品猪体温范围为36.4~42.6℃,月平均体温最低38.8℃,最高40.6℃,平均为39.4℃。6、7、8月体温最高,1、2、3月最低。母性比公性体温高,长白比本地黑猪体温高。  相似文献   
94.
"Encéphale isolé" cats were implanted with two push-pull cannulae, one in the left caudate nucleus and the other in the ipsilateral substantia nigra. L-3,5(-3)H-Tyrosine was introduced continuously into the caudate nucleus to study the release of 3H-DA. Glycine (10(-5)M) added to the superfusing medium of the push-pull cannula inserted into the substantia nigra reduced (25%) the spontaneous release of 3H-DA. Conversely, strychnine (10(-5)M) slightly stimulated the 3H-transmitter release. The inhibiting effect of glycine (10(-5)M) on 3H-DA release was no longer seen in the presence of strychnine (10(-5) M). The results support the hypothesis of a tonic glycinergic inhibitory control of the activity of the nigrostriatal dopaminergic neurons.  相似文献   
95.
The effects of the biogenic amine reuptake inhibitors fluoxetine, clomipramine and imipramine on the behaviour of rats after chronic treatment with 9 tetrahydrocannabinol ( 9-THC) for 5 and 10 days were examined. Rats with permanently in-dwelling IV cannulae were injected twice daily with doses of 9-THC (2–6 mg/kg). 9-THC treatment reduced the rate of body weight gain and induced the typical biphasic modifications of behaviour. Tolerance developed to both of these effects. On days 6 and 11 of the experiment, rats were injected IP with 15 mg/kg imipramine HCl, clomipramine HCl or fluoxetine HCl, and behaviour, consisting of writhes, backward kicks, jumps and wet shakes, was observed for the next 30 min. Each of the amine reuptake inhibitors induced changes in behaviour, the severity of which appeared to correlate with their ability to inhibit the reuptake of 5-hydroxytryptamine (5-HT). It is suggested that tryptaminergic mechanisms are involved in the production of a withdrawal-like behaviour after chronic 9-THC treatment.  相似文献   
96.
Summary Inactivation of GABA was inhibited by -vinyl GABA (GVG) and the effects of the increased GABA level in the brain on blood pressure and body weight of spontaneously hypertensive rats (SHR) and normotensive rats (WKY) were investigated.When started at the age of 8 weeks or 5 weeks, treatment of SHR and WKY with GVG (150 mg/kg, s.c.) for several weeks did not influence systolic blood pressure. In 1-week old SHR, treatment with GVG (up to 150 mg/kg, s.c.) abolished the rise in blood pressure until animals were 8 weeks old. Thereafter, arterial blood pressure started to increase but it remained distinctly lower than that in untreated animals. When started at the age of 1 week, treatment with GVG for 7 weeks did not influence arterial blood pressure in WKY. GVG delayed increase in body weight in SHR and WKY, irrespective of their age. GVG greatly increased GABA levels in the hypothalamus, frontal cortex, brainstem and rest of the brain in both WKY and SHR.It is concluded that an increase in the GABA level in the brain leads to a delay in the development of hypertension in young SHR. Hence, development of genetic hypertension seems to be susceptible to activation of the GABAergic system in a very early critical phase only. Send offprint requests to N. Singewald at the above addressThis work was supported by the Fonds zur Förderung der wissenschaftlichen Forschung  相似文献   
97.
Two new approaches in suction lipectomy of the buttocks region are described: liposuction of the banana and liposuction of the sensuous triangle. The banana is the highest part of the posterior thigh just below the buttocks crease. It appears only in certain individuals and appears as a buldge under the buttocks crease. The preferred approach to liposuction of the banana is discussed as well as a theory as to its etiology. A common complication of liposuction of this area is ptosis of the buttocks crease. Methods of treatment of this complication are also discussed. The second topic addressed is liposuction of the sensuous triangle which is at the junction of the lateral buttocks, lateral thigh, and posterior thigh. The result of suctioning this area is a more athletic-appearing buttocks region.Presented at the 7th Annual Meeting of the Lipoplasty Society of North America, San Francisco, California, October 29, 1989  相似文献   
98.
Prostaglandin E1-induced hypotension (25% reduction from the preadministration level in mean arterial pressure) was applied to thirteen patients. Eight patients among them were operated in the supine position (group I) and other five in the prone position (group II). The maintenance dose of PGE1 was considerably lower in group II than in group I (0.067µg·kg–1·min–1 vs. 0.119µg·kg–1·min–1). In group I, there was a significant increase in CI, with a significant decrease in SVRI and PVRI during PGE1-induced hypotension. Such a high dose of PGE1 (0.119µg·kg–1·min–1) was considered to have a direct dilating action on the systemic resistance bed as well as on the pulmonary vasculature. It was considered that the suppression of hypoxic pulmonary vasoconstriction could be a mechanism to increase venous admixture during PGE1-induced hypotension. In group II, there was no significant increase in CI, and no significant decrease in SVRI and PVRI. PGE1-induced hypotension can be safely applied to the anesthetized patients, but we should be careful to apply it to the patients in the prone position, because lower dose of PGE1 can induce severe hypotension, which is not accompanied by the increase in CI as occures in the patients in the supine position.(Hirose M, Yoda K, Sakai K, et al.: Comparative Study on the cardio-respiratory change during prostaglandin E1-induced hypotention in the patients in the supine and prone position. J Anesth 5: 30–35, 1991)  相似文献   
99.
This Capsular Lens (ONG, type IV, to be called O.C.L.) has been developed for routinely performed extracapsular cataract extraction with lens implantation. The fundamental surgical procedure was based on continuing experience with the bimanual aspiration-irrigation technique and system developed by the author in 1971. The biomechanical properties of the asymmetric partly flexible, haptic loops are designed to give tensionfree fixation in two capsular pockets. The plano-anterior position of the lens ensures well-defined irido-lenticular clearance and proper alignment of the convex side with the posterior capsule. Consequently no iridectomy or iridotomy is needed for proper aqueous flow.  相似文献   
100.
Summary Further analysis of temperature rhythms obtained in an earlier study of 38 subjects subjected to an 8-h eastward transmeridian flight showed that the extent to which the phase of the rhythm was shifted after the flight was related to the phase angle of the pre-flight rhythm. Late peakers shifted more than early peakers, and this difference between the two types was still as large after 12 days in the new time zone as on the first day. Because the phase-shift was an advance one, this meant that the pre-flight individual differences in phase-angle were abolished by the flight, and had not re-appeared by the end of the observation period. It is suggested that this may have been due to an increase in the rigidity of the routine in the post-flight stage of the study, and that a similar effect may also occur in a switch from day to shiftwork.  相似文献   
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