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81.
应用食道心房调博缩测定健康小儿窦房结功能,以了解西宁地区正常数值与平原地区进行对比。选择27例健康小儿,将F6二级电极导管从鼻腔送入,定位地食道心电图最大正负双相P波处,采用苏州东方电子仪器厂生产的DF-3A型心脏电生理治疗仪进行检查,从而作出诊断。  相似文献   
82.
83.
The sniff magnitude test (SMT) is a reliable and rapid clinical test of olfactory function that is minimally dependent on cognitive and linguistic abilities. In this study, we compared performance on the SMT and University of Pennsylvania Smell Identification Test (UPSIT) in samples of children and nonnative English speakers. Previous research has shown that these populations perform poorly on the UPSIT as compared with young, healthy U.S. adults. Such performance differences may reflect variations in memory/cognition and language/culture rather than olfactory abilities. The UPSIT scores of children and of Indian and Chinese graduate students were found to be lower than those of young U.S. adults. By contrast, these groups did not perform more poorly than U.S. adults did on the SMT. The results are consistent with findings from our studies, with the elderly showing that performance on the UPSIT, but not the SMT, is significantly correlated with measures of memory, language and other cognitive abilities. The findings highlight the utility of the SMT when evaluating the olfactory ability of the very young, older adults and people with diverse linguistic and cultural backgrounds.  相似文献   
84.
Summary The ventilatory anaerobic threshold (VAT) during graded exercise was defined as the oxygen uptake ( ) immediately below the exercise intensity at which pulmonary ventilation increased disproportionally relative to . Since VAT is considered to be a sensitive and noninvasive measure for evaluating cardiorespiratoy endurance performance, the purpose of the present study was to determine normal values in children. We examined 257 healthy children (140 boys and 117 girls) varying in age from 5.7 to 18.5 years, during treadmill exercise. The data were analyzed in relation to sex and age. In boys the lowest (ml · min−1 · kg−1) was found in the youngest age group (5–6 year). In girls, on the other hand, no significant increase occurred with age. For VAT, expressed as ml O2 · min−1 · kg−1 or as a percent of a significant decrease was found in boys and girls with age. This suggests an increase in lactacid anaerobic capacity during growth. In contrast to observations in adults, only low correlations were found between and VAT (r=0.28 in boys and r=0.52 in girls), which suggests that the development of the underlying physiological mechanism does not occur at the same rate in growing children. These data provide normal values for VAT that can be used for clinical exercise testing in the pediatric age group.  相似文献   
85.
HIV-1 vertical transmission is thought to mainly take place by virus crossing the placental barrier. However, the mechanism by which HIV-1-infects placental cells remains to be elucidated. We have found that purified cytotrophoblasts as well as trophoblastic cell lines are susceptible to infection by different HIV-1 isolates as detected by DNA-PCR and release of infectious virus, although with very low efficiency. Purified trophoblast or trophoblastic cell lines express low levels of chemokine receptors CCR-5 and CXCR-4 but not CD4 on the cell surface. To test if those molecules were used as receptors for HIV-1 infection, placental cells were pretreated with antibodies to CD4, CC-chemokines, C-X-C chemokines. None of those treatments inhibited HIV-1 infection. In contrast, we have found that HIV-1 infection of placental cells was increased in cocultures of infected T-cell blasts and placental cells. More interestingly, antibodies to beta(2) integrins and to LFA-1 were able to significantly block infection of placental cells. Cell surface expression of ICAM-1, an adhesion molecule involved in attachment of leukocytes to placenta, was upregulated in HIV-1-infected placental cells. Placental cells were able to transfer HIV-1 infection to T-cell blasts. This transmission required cell to cell contact and was also inhibited by anti-LFA-1 antibodies. In summary our results suggest that placental trophoblast could be infected by HIV-1 by a mechanism involving T cell to placental contact. Moreover, placental infection enhanced ICAM-1 expression and leukocyte adherence, an event which was required to transfer HIV-1 infection to T cells. This provides an explanation of the virus passing through the placental barrier during in utero HIV-1 vertical transmission.  相似文献   
86.
Malignant salivary gland tumors in children are very rare. This report describes the autopsy of a child with parotid gland cancer. The patient, a 10 month old girl, was admitted to the Nagoya First Red Cross Hospital with facial nerve palsy. lncisional biopsy of a post-auricular tumor was performed, and undifferentiated carcinoma was diagnosed. The patient died 6 months later of respiratory failure due to pulmonary lymphangitis carcinomatosis. Light and electron microscopic and immunohistochemical examinations of the tumor tissue were performed. The tumor cells were arranged in a medullary, sheet-like manner. Keratinization or mucus lakes were not observed. PAS-alcian blue staining demonstrated intracytoplasmic mucus as granules, and also small intercellular droplets of mucus that might otherwise have been unnoticed. Ultrastructurally, some of the tumor cells had tonofilament-like keratin filaments, and also small hollow spaces bounded by microvilli and containing secretory particles. These were stained by antisera against CEA and keratin. These findings are suggestive of differentiation to mucoepider-moid carcinoma. We also review and discuss malignant salivary tumors of epithelial origin in children. Acta Pathol Jpn 40: 149–152, 1990.  相似文献   
87.
Summary The purpose of this study was to investigate the validity of heart rate (f c) and ratings of perceived exertion (RPE) as indices of exercise intensity in a group of children while swimming. Six healthy male swimmers, aged 10–12, swam tethered using the breast-stroke in a flume. The resistance started at 1.0 kg and increased in 1.0 kg steps up to the point of their exhaustion. The subjects swam for 5 min during each period, with a rest of 10–20 min until they had returned to their resting f c level. The last exercise intensity was with the maximal mass the subjects could support for 2 min. The last min of oxygen consumption (VO2) and 30 s of f c were measured during each exercise period. The subjects gave their RPE assessment at the end of exercise.The individual relationships between f c and VO2, and percentage maximal oxygen consumption (% VO2max, were linear with a high correlation r=0.962–0.996 and r=0.962–0.996, respectively. Therefore, it was concluded that f c was valid as an index of the exercise intensity of children while swimming. Compared to the results found in adults using a similar protocol, the children's f c were 8.3–26.9 beats·min–1 higher than those of the adults at the given % VO2max. The present study showed two different patterns in the relationship between VO2 and RPE in individuals. In two subjects the RPE increased linearly with VO2 while in the other four subjects the increase was discontinuous. If f c and RPE were to be applied to the setting and evaluation of exercise intensity during swimming, it would seem that f c would be a more useful guide than RPE for some children.  相似文献   
88.
Sera of 86 patients clinically sensitive to foods were tested by passive sensitization of human and/or monkey lung (127 tests) and the radioallergosorbent test (RAST) (72 tests), using whole-food antigens; the results were compared with skin (prick) testing. Results of the prick test correlated with history in 76% of cases; lung sensitization correlated with history in 37% and with prick test in 57%; and RAST correlated with history in 54% and prick test in 72%. It is concluded that a very large percentage of adverse reactions to foods are IgE-mediated. The prick test is of use in diagnosis, particularly when combined with RAST; the lung sensitization test is technically impractical and not a reliable indicator. The best diagnostic method is careful history with food challenge and withdrawal and rechallenge; the latter is safe except in patients with a history of violent reaction.  相似文献   
89.
本文报告小儿遗传咨询门诊及新生儿科确诊的遗传病:染色体病23例,其中核型异常16例,结构异常7例;常染色体显性遗传病11例,常染色体隐性遗传病28例;性连锁遗传病6例;血红蛋白异常1例,共计69例。常染色体遗传病占55%,染色体异常综合征占33%。常染色体病种类繁多,尽管发病率不高,但危害很大,给诊断带来困难。  相似文献   
90.
Although infantile myofibromatosis (IM) is the most common fibrous proliferation of infancy, many aspects of this benign lesion have not been explored. IM histogenesis is still poorly understood, despite immunohistochemical staining and ultrastructural features that suggest a myofibroblastic origin. IM diagnosis is often made difficult by the predominance of small primitive spindle cells over myofibrobasts and the presence of intravascular growth. Genetic information is scarce, with only one karyotyped case. Here we describe a case of solitary IM discovered at birth in an otherwise healthy girl. The tumor was well circumscribed, arranged in nodules and made up of ovoid cells without atypia, in a myxoid background. Immunohistochemical evaluation indicated a myofibroblastic differentiation. The cytogenetic and fluorescence in situ hybridization analyses revealed an abnormal chromosome 9, derived from an unbalanced whole-arm translocation between chromosomes 9 and 16. On both chromosomes, the breakpoints were located in the pericentric heterochromatic region. This clonal abnormality has not been reported in other tumors and is different from the chromosome 6q deletion reported in the single previous reported IM karyotype.  相似文献   
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