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151.
The ability of amphetamine to induce expression of the immediate early gene protein, Fos, was examined by immunocytochemistry in animals with unilateral 6-hydroxydopamine lesions of the nigrostriatal bundle. Amphetamine induced Fos expression in the globus pallidus (GP) on the intact side of the brain, but this response was greatly attenuated on the dopamine-depleted side. In contrast, amphetamine induced little Fos expression in the entopeduncular nucleus (EPN) and the substantia nigra pars reticulata (SNpr) on the intact side of the brain, but resulted in pronounced expression in these structures on the lesioned side. These findings demonstrate that unilateral dopamine depletion results in a pathophysiological state in which some responses to amphetamine are attenuated while others are paradoxically potentiated. One explanation of these effects is that amphetamine may indirectly activate excitatory inputs to the SNpr and the EPN on both sides of the brain. On the intact side, these effects would be opposed by the simultaneous activation of inhibitory pathways arising in the striatum and the GP, with the result that little Fos expression would be seen. On the dopamine-depleted side, however, engagement of these inhibitory pathways would be attenuated and the unopposed effects of the excitatory inputs mobilized by amphetamine would result in exaggerated Fos synthesis. 相似文献
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153.
In order to clarify the association between apolipoprotein E4 (ApoE4) and the pathogenesis of Alzheimer's disease (AD), we analyzed the distribution of the apolipoprotein E (ApoE) phenotypes and the frequency of the apo E alleles epsilon2, epsilon3, and epsilon4 in Japanese healthy controls (n = 1090, an average age of 51.2+/-12.6 years) and demented patients (n=103, mean age of 73.6+/-9.2 years). Demented subjects were divided into three subgroups: early-onset AD group (EOAD; n=25, mean age 63.0+/-6.2 years), late-onset AD group (LOAD; n=33, mean age 79.3+/-5.1 years), and vascular dementia group (VD; n=45, mean age 75.3+/-8.0 years). The apolipoprotein E phenotype was determined by isoelectric focusing and immunoblotting. There were no significant differences in the distribution of the apo E phenotypes by gender or age, and the estimated frequencies of epsilon2, epsilon3 and epsilon4 were 0.05, 0.86 and 0.09, respectively, in the normal controls. There was a significant difference in the distribution of the apo E phenotypes between LOAD and elderly controls aged more than 65 years (P<0.0001). The distribution of the apo E phenotypes in EOAD was the same as that in LOAD. The frequency of the epsilon4 allele was significantly higher in LOAD (0.35, P<0.0001) and EOAD (0.28, P<0.0001) than that in the control subjects (0.07), but not in VD (0.12, P=0.1630). The present findings suggest that ApoE4 is related with both EOAD and LOAD, but not with VD, and support the hypothesis that it is a genetic risk factor of AD. 相似文献
154.
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156.
药流与负压吸宫法的效果和可接受性研究 总被引:5,自引:1,他引:4
研究的目的:比较RU486/Cytotec药物和负压吸宫术两种流产方法的效果,以及医学的和个人的可接受性.对象为通过咨询,介绍两种流产方法后,让对象自愿选择而组成.年龄在20~34岁.药物组100例,闭经35~42天,第1天口服RU486 600mg,第3天服Cytotec(PGE1)0.4mg,第17、43天回医院随访.手术组100例,闭经≤56天,负压吸宫术后第14、43天回医院随访.结果:完全流产率药物组为89%,手术组为100%.对象选择这两种流产方法的主要原因:药物组94%的人认为痛苦少,手术组的55%认为手术快、节省时间,而且手术同时可取出或放置宫内节育器(占45%).结论:RU486/Cytotec药物流产和负压吸宫术在各自适合的人群中都具有高度的可接受性.两种方法各具优缺点,不能相互取代,二者相辅相成,取长补短,将使终止妊娠的措施更为安全 相似文献
157.
This prospective controlled study investigated the concentrationsof free -human chorionic gonadotrophin (HCG) subunit in 554women with a singleton intrauterine or tubal pregnancy. Theypresented with vaginal bleeding and/or abdominal pain in thefirst 18 weeks of pregnancy. The control group comprised 156women with musculo-skeletal pain and no vaginal bleeding. Theirpregnancies continued to term. The study group comprised 398women (141 threatened-continuing pregnancies, 37 threatened-miscarriages,185 non-continuing pregnancies and 35 tubal pregnancies). Free-HCG concentrations were significantly lower in the non-continuing,threatened-miscarriage and tubal pregnancy groups [mean 4.62,6.50 and 4.27 ng/ml respectively; 95% confidence interval (CI)3.75-5.69, 4.469.48 and 2.926.2 respectively]than in the control and threatened-continuing groups (mean 41.61and 48.22 ng/ml respectively; 95% CI 34.5350.13 and 42.0355.32respectively) (P < 0.001 in all cases). A cut-off value at20 ng/ml was found to differentiate between the viable(control and threatened-continuing) and the abnormal(non-continuing, threatened-miscarriage and tubal) pregnancies,with 88.3% sensitivity and 82.6% positive predictive value.An excellent diagnostic and prognostic usability of free HCGwas confirmed by a receiver operating characteristic curve plotIn conclusion, a single serum free -HCG measurement taken inearly pregnancy is valuable in the immediate diagnosis of earlypregnancy failure and the long-term prognosis of viability. 相似文献
158.
159.
Friauf E 《The European journal of neuroscience》1992,4(9):798-812
Immediate éarly genes such as the proto-oncogene c- fos can be expressed in neurons following synaptic excitation by sensory stimulation. C- fos immunocytochemistry has subsequently been shown to be a very sensitive marking technique for neuronal activity. Here, antibodies against the c- fos protein product Fos were used to map the tonotopic organization in the auditory system of adult and developing rats. After stimulating adult rats with pure-tone pulses, bands of Fos-immunoreactive neurons revealed the frequency representation in seven brainstem nuclei: all three subdivisions of the cochlear nucleus, the lateral superior olive, the medial nucleus of the trapezoid body, the ventral nucleus of the trapezoid body, the rostral periolivary nucleus, the dorsal nucleus of the lateral lemniscus and the inferior colliculus. With the exception of the dorsal cochlear nucleus and the inferior colliculus, tonotopicity has not been previously demonstrated in the brainstem nuclei of the rat. During development two striking results were obtained. First, beginning at postnatal day 14 (i.e. ∼2 days after physiological hearing begins in rats), not only low but also high frequencies were able to induce strong Fos immunoreactivity, indicating that gradual recruitment of formerly unresponsive high-frequency sites does not occur in the rat. Second, a gradual age-related shift of the position of isofrequency bands was not seen in any of the nuclei, suggesting that changes in frequency-place code do not occur after 2 weeks postnatally. These results indicate that the rat's auditory brainstem nuclei achieve their adult-like tonotopic organization early on, implying a somewhat different developmental time course than is found in other mammalian species. 相似文献
160.
The experience and early complications in 66 morbidly obese patients who underwent biliopancreatic diversion are presented.
There was one death, due to a pulmonary embolus (PE) at home on the 15th postoperative day. Postoperative complications occurred
in nine patients, consisting of gastric hemorrhage (2), gastric outlet obstruction (2), non-lethal PE (1), deep vein thrombosis
(1), wound dehiscence (1), and asymptomatic gastric leak (1). In addition, there were 12 superficial wound infections. Four
patients required urgent reoperation for gastric hemorrhage (2), gastric outlet obstruction (1), and wound dehiscence (1).
The high complication rate is believed to represent the early part of the learning curve. Some reports of the early complications
following other bariatric operations are discussed. 相似文献