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41.
基因芯片对PMA激活的血管内皮细胞早期反应基因的研究   总被引:4,自引:1,他引:3  
目的 :用基因芯片研究 PMA激活的血管内皮细胞的早期反应基因 (imm ediate early response gene,ERG)。方法 :以包含 40 96条人类基因的 DNA芯片检测血管内皮细胞受代谢增强剂 PMA(phorbol myristate acetate)激活后早期的基因表达谱 ,并从中筛查出 ERG。结果 :血管内皮细胞受 PMA作用 6 h后 ,17条基因上调 ,11条下调。数据处理聚类分析表明 17条上调基因中多数 (13/ 17)属蛋白质磷酸酶和转录调控因子基因 ,而下调基因中多数 (9/ 11)为细胞分裂相关基因。结论 :证明PMA激活的人血管内皮细胞早期反应基因主要是转录调控因子和蛋白质磷酸酶基因。  相似文献   
42.
Assessment of the quality of life (QoL) of human immunodeficiency virus (HIV)-infected subjects is often based on questionnaires in which the items or questions are not seen to be relevant by patients, nor by the users of the data obtained. It therefore seemed appropriate to return to the issue. The methodological and bibliographical research as well as the consultations we conducted convinced us that the elaboration of a new questionnaire was both necessary and possible. In order to do so, we adopted methodological principles based on the Sickness Impact Profile development methodology. First a bibliographical research was conducted in order to study instruments already used for HIV infection. Then, experts concerned with HIV infection and members of patients' associations were interviewed to assess how opportune the development of a new instrument could be. Following this, a methodology was established for the design and construction of the new instrument. One hundred and eighteen candidate questions were generated from an analysis of the content of 20 patients' interviews, which were subsequently submitted to 102 patients, to obtain finally a set of 31 questions from the interpretation of the results obtained from classic psychometric analysis and also from non-classic methods (item response theory and Rasch model). The concept being measured is the impact of illness being experienced by HIV-infected subjects from their own perspective. The range of health states covered by this questionnaire relates to fairly mild conditions. Rasch analysis of this set of 31 questions (HIV-QL31) shows that it corresponds to one unidimensional construct. A single score can be calculated by simple summation of dichotomous response options. This score is highly reliable (Cronbach's coefficient = 0.93) and is also discriminant regarding the severity of clinical status.  相似文献   
43.
A method is described for investigating life course influences on health in early old age. The lives of some 300 individuals at present aged 65-75 y have been reconstructed from the archived records of a pre-WWII survey, in which they took part as children, and from lifegrid interviews with the same individuals 60 y later. Despite loss to study at several points those interviewed are shown to be representative of the British population socio-demographically, in comparison with the 1931 and 1991 decennial censuses, and physically, in comparison with the Health Survey for England. Bias is conservative because the most disadvantaged were disproportionately affected by loss to follow-up through death and because non-responders to interview were more disadvantaged as children than the interviewees. Representativeness and conservative bias, it is argued, justify the use of these data for investigating life course influences on health in early old age.  相似文献   
44.
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   
45.
46.
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   
47.
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   
48.
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   
49.
Basal expression of the protein products of the inducible immediate early genes (IEGs), c-Fos and Zif268, was investigated in five regions of the rat basal ganglia using immunohistochemistry. In particular, high basal levels of Zif268 but very low levels of c-Fos were seen in the caudate-putamen (CPu). Double immunostaining revealed that many of the constitutively expressed Zif268-positive neurons were GABAergic but very few were cholinergic or neuronal nitric oxide synthase (nNOS)-positive, and some of the Zif268-positive neurons were also immunopositive for a glutamate NMDA receptor subunit NR1 or NR2A. No regional difference between the medial and lateral parts of the CPu was observed in the cellular phenotypes of Zif268-positive neurons. Almost no basal levels of Zif268 were seen in the other four regions: the globus pallidus, entopeduncular nucleus, subthalamic nucleus and substantia nigra pars reticulata. As in the CPu, negligible levels of c-Fos were seen in these four regions. Differential expression of these two IEGs may suggest gene-specific and region-specific functions of c-Fos and Zif268 in the basal ganglia. Constitutive expression of Zif268 existing mainly in the GABAergic neurons in the CPu may at least in part be maintained by glutamatergic afferents.  相似文献   
50.
Objective Discussion of diagnosis, treatment and prognosis of non-palpable TO breast cancer. Methods Between 1978 and 1997, 9,980 female patients with operable breast cancer were treated surgically, of which 276 were determined to have TO breast cancer. Most TO breast cancers could be detected promptly with careful examination of presenting symptoms, such as nipple discharge, local thickening of the breast, nipple erosion, nipple retraction and postmenopausal mastalgia, while 12 cases were detected by routine mammography of the contralateral breast. Results All patients were treated surgically and their tissue subjected to histopathological examination. Most cases (73.0%) were noninvasive or early invasive carcinoma. Axillary lymph nodes metastases were found in 7.69% of 234 mastectomy cases. Conclusion The survival rate was significantly increased if the tumor was in an early stage. The 5-, 10-, 15-years survival rates were 98.1%, 94.6% and 90.3%, respectively.  相似文献   
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