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991.
992.
OBJECTIVES: To determine the usefulness of electrocardiography (ECG) and chest radiography (CXR) in evaluation of patients referred to the pediatric cardiologist for the evaluation of heart murmur or chest pain. DESIGN: In this prospective study, 106 consecutive outpatients were categorized with no heart disease, possible heart disease, or definite heart disease based on history and physical examination; they then underwent ECG and CXR. Studies were reviewed and the examining cardiologist could change the diagnosis and order an echocardiogram. SETTING: Academic pediatric cardiology practice. RESULTS: In patients thought to have no heart disease, the diagnosis was changed to definite heart disease in four solely on the basis of abnormal CXR or ECG. In 25 patients thought to have possible heart disease, the diagnosis was changed to no heart disease (7) or definite heart disease (5) after review of the CXR and ECG. All 25 patients diagnosed with definite heart disease had this confirmed by abnormal CXR (2), ECG (3), both abnormal CXR and ECG, or echocardiogram (18). CONCLUSIONS: ECG and CXR helped diagnose heart disease in four patients thought to have no heart disease, helped to rule out lesions in seven patients with possible heart disease, helped diagnose heart disease in five patients thought to have possible heart disease, and helped confirm heart disease in nine patients. In these days of cost containment, routine ECG and CXR continue to be valuable tools for the pediatric cardiologist in evaluation of patients with heart murmurs or chest pain. 相似文献
993.
994.
Middle-latency somatosensory evoked potentials (MLSEPs) were recorded from 19 scalp electrodes in ten male patients with the fragile X (fraX) syndrome and nine normal controls. One fraX patient was found presenting the so-called “giant” MLSEPs with an amplitude of N60 of about 60 μV and of 40 μV after stimulation of the right and left median nerves, respectively. Tapping of the right hand, in the same patient, induced the appearance of left parietal evoked EEG spikes. These findings further support the already suggested similarity between the epileptic picture of several fraX patients with that of the benign childhood epilepsy with centrotemporal spikes. Color mapping of the MLSEPs recorded in the remaining nine patients, when compared with the control group, showed an abnormally large N30 over the frontal regions, together with an increase in amplitude of P27, over the parietal areas, and of N60 and P100 which also presented abnormal field distributions, being represented preferentially over the frontal regions. These data could suggest the existence of a cortical dysfunction mostly involving the frontal lobes (supplementary motor area, in particular) in the fraX syndrome which could support many behavioral changes usually observed in these patients.
Résumé
Les potentiels évoqués somesthésiques à latence moyenne (MLSEPs) du nerf médian ont été enregistrés avec 19 électrodes chez dix sujets avec le syndrome du chromosome X fragile (fraX) et neuf sujets normaux. Nous avons observé un sujet avec fraX et des MLSEPs géants et une amplitude de l'onde N60 de 60 μV après stimulation du nerf médian droit et de 40 μV après stimulation gauche. Après le toucher de la main gauche, chez le même sujet, on a observé l'apparition de pointes épileptiques pariétales à l'EEG. Ces résultats confirment l'hypothèse déjà proposée de la similitude entre l'épilepsie présentée par quelques sujets avec fraX et l'épilepsie bénigne de l'enfant avec pointes centrotemporales. La cartographie des MLSEPs obtenue chez les neuf autres sujets et confrontée à celle du groupe contrôle a mis en évidence une onde N30 avec amplitude anormalement augmentée sur les régions frontales, une augmentation de l'amplitude de P27 sur les régions pariétales, et de N60 et P100, qui montraient aussi une anormalité de la distribution topographique ; en effet, elles étaient mieux représentées sur les régions frontales. Ces données peuvent indiquer l'existence d'un dysfonctionnement des lobes frontaux (en particulier de l'aire motrice supplémentaire), dans le syndrome du chromosome X fragile, qui peut se corréler à plusieurs modifications du comportement généralement observées chez ces patients. 相似文献995.
Knowledge and awareness of risk factors for cardiovascular disease among Canadians 55 to 74 years of age: results from the Canadian Heart Health Surveys, 1986-1992 总被引:2,自引:1,他引:1 下载免费PDF全文
996.
997.
目的 研究不同脑区内c-fos和c-jun 蛋白的表达与不同方式应激之间的关系。方法 采用特异性抗体的原位免疫细胞化学方法,对强迫游泳和束缚应激后大鼠脑皮层、海马、下丘脑及小脑内fos和jun 蛋白阳性神经元的分布进行观察,用图像分析技术对大鼠额皮层(FC)、海马齿状核(DG)、下丘脑室旁核(PVN)及小脑颗粒细胞层(GCL)内的fos和jun 阳性细胞的相对切面面积比和平均目标灰度进行分析。结果 两种方式应激结束后3h,脑皮层的额叶和颞叶、海马的CA1 和DG及下丘脑的PVN、视上核、背内侧核均有较强的c-fos和c-jun 表达。图像分析结果发现,在FC、DG及PVN 区域,两种应激后c-fos和c-jun 阳性胞体相对切面面积比相似,均高于正常大鼠(P< 0.05),而平均目标灰度,则显著降低(P< 0.05),而在GCL,强迫游泳应激组的FOS阳性胞体面积比高于束缚应激组,亦有显著性差异。结论 不同的应激方式诱导相关脑区c-fos和c-jun 的表达基本一致,强迫游泳可能具有更多躯体方面的效应。 相似文献
998.
Promotion of estrogen-induced mammary gland carcinogenesis by androgen in the male Noble rat: probable mediation by steroid receptors 总被引:1,自引:0,他引:1
Both endogenous and exogenous estrogen exposure is associated with an
increased breast cancer risk. In some studies, elevated serum testosterone
levels have also been linked to an increased breast cancer risk. Estrogen
alone or combined with progesterone induces high mammary tumor incidences
in various strains of both male and female rats. Mammary gland ductal
adenocarcinomas were induced after 17beta- estradiol (E2) and testosterone
propionate (TP) treatment in male Noble rats. Tumor incidence was 100%
after 8-9 months of treatment. Such neoplasms were not detected after
either estrogen or androgen exposure alone within this time period. TP
alone caused disruption of mammary gland ducts and proliferation of stromal
tissue, while E2 treatment alone induced both ductal epithelial growth and
nodular atypical hyperplasia. To study the interaction of these hormones in
mammary tumorigenesis, sex hormone receptors were characterized in mammary
glands of Noble rats. Estrogen receptor-alpha (ER) was detected in age-
matched, untreated mammary gland epithelium; in most early atypical
hyperplastic lesions appearing after E2 and E2 + TP treatment and in E2 +
TP-induced mammary tumors. Two major ER putative isoforms, 116 and 120 kDa,
were detected in E2- and E2 + TP-treated mammary glands, and in the induced
tumors. A 54 kDa ER protein was found in untreated and TP-treated mammary
glands, and in the induced tumors. Both progesterone receptor-B (PR-B) and
PR-A2, as well as androgen receptor-B (AR-B) and AR-A isoforms were
markedly elevated in all E2 + TP-induced mammary tumors. However, the
levels of both PR and AR were very low in mammary glands of E2- and E2 +
TP-treated male rats. Low and moderate levels of AR and PR, respectively,
were detected in most atypical hyperplastic lesions induced by E2- and E2 +
TP-treated mammary glands. These results suggest that androgens may
interact with either AR or PR, and perhaps both receptors, in E2 +
TP-induced mammary glands and the induced tumors to effect the reduction in
latency period, enhance tumor size, and increase incidence to 100%.
相似文献
999.
Jones-Bolin SE; Johansson E; Palmisano WA; Anderson MW; Wiest JS; Belinsky SA 《Carcinogenesis》1998,19(8):1503-1508
Differences in tumor formation among inbred mouse strains with high (A/J)
and low (C3H) susceptibility for lung cancer have been linked to a
repetitive element within the second intron of the K-ras gene. The purpose
of this investigation was to determine whether differences within the K-ras
gene promoter region or the intron 2 polymorphism affect K-ras gene
expression in lung tumors and target alveolar type II cells isolated from
A/J and C3H mice. Ribonuclease protection assays were performed using RNA
isolated from 4-(methylnitrosamino)-1-(3- pyridyl)-1-butanone (NNK)-induced
lung tumors from each mouse strain and alveolar type II cells isolated from
A/J and C3H mice. An 838 bp fragment of the murine K-ras gene promoter
region was amplified by PCR, cloned and sequenced from both mouse strains.
Promoter regions from both mouse strains were inserted into a luciferase
reporter gene vector, with and without the second intron polymorphism, and
transfected into sensitive, intermediate and resistant lung tumor cell
lines. No significant differences in K-ras gene promoter activity was found
between the two strains using these specific reporter gene constructs.
Consistent with these results, levels of K-ras expression did not differ
between alveolar type II cells, whole lung or tumors induced by NNK in A/J
or C3H mice. Moreover, in lung tumor cell lines derived from mice with
differing susceptibility for lung cancer, K-ras expression did not
correlate with the growth rate of tumors induced in nude mice from these
cell lines. These results indicate that factors involved in modulating the
rapid clonal expansion of the mutated K-ras allele from A/J mice are not
directly linked to expression of this gene. Other genetic changes or losses
in conjunction with hypothesized modifier loci, such as the Par1 locus,
must play a significant role in establishing the phenotypic strain
differences for lung tumor formation.
相似文献
1000.
AIMS: To assess compliance with Department of Health guidelines on weaning practice in a representative sample of 127 infants from Glasgow, and to identify factors influencing timing of weaning. METHODS: Questionnaires on feeding and weaning were completed during home visits. Ninety eight mothers completed a further questionnaire on attitudes to weaning. RESULTS: Median age at introduction of solid food was 11 weeks (range 4-35 weeks); only 7% of infants had not been weaned before age 4 months. There was no difference in timing of weaning between boys and girls. Younger mothers (< 20 years old), those of lower socioeconomic status, and those who formula fed their infants tended to introduce solids earlier. Infants who were heaviest before weaning were weaned earlier. Seventy three of 98 mothers reported that they weaned their babies because they felt that they required more food. Sources of information influencing time of weaning were previous experience (53/98), books and leaflets (43/98), advice from the health visitor (31/98), and family and friends (15/98). Sixty five of 98 mothers reported receiving formal information on weaning, in most cases (54) this was from the health visitor. Mothers who received formal information tended to wean their infants later. Two per cent of infants had been given cow's milk as a main drink by age 6 months, 17% by 9 months, and 45% by the end of the first year. CONCLUSION: Compliance with recommendations on timing of weaning (not before 4 months), weaning foods, and cow's milk consumption in Glasgow is poor, although no poorer than in many other areas of the UK as found by Office of Population, Censuses and Surveys. Public health messages in relation to weaning may not be reaching their target audience. 相似文献