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排序方式: 共有864条查询结果,搜索用时 31 毫秒
1.
Sonoelasticity imaging of prostate cancer: in vitro results 总被引:2,自引:0,他引:2
2.
Screening for early ovarian cancer 总被引:5,自引:0,他引:5
3.
Irregularly shaped small shadows on chest radiographs, dust exposure, and lung function in coalworkers' pneumoconiosis. 下载免费PDF全文
H P Collins J A Dick J G Bennett P O Pern M A Rickards D J Thomas J S Washington M Jacobsen 《Occupational and environmental medicine》1988,45(1):43-55
The predominant shapes of small opacities on the chest radiographs of 895 British coalminers have been studied. The aims were to determine whether irregular (as distinct from rounded) small opacities can be identified reproducibly, whether their occurrence is related to dust exposure, and whether they are associated with excess prevalence of respiratory symptoms or impairments of lung function. Six of the doctors responsible for regular radiological surveys of all British coalminers each classified all 895 radiographs twice and independently, using the International Labour Organisation's 1980 classification system. The majority view was that 39 films showed predominantly irregular small opacities, 131 showed predominantly small rounded opacities, and 587 showed no small opacities. Readers' opinions varied about the presence and shapes of shadows on the other 138 films. In general, consistency between readers (and within readers on repeated viewings) was satisfactory. The occurrence and profusion of irregular shadows were related significantly both to the men's ages and additionally to their cumulative exposure to respirable coalmine dust as determined from 15 years' dust monitoring close to where the miners had worked. For any given level of exposure, the average level of profusion of the small irregular opacities was less than the corresponding profusion of small rounded opacities. The prevalence rates of chronic cough and phlegm, and of breathlessness, were higher in those with small irregular opacities than in those with no small opacities (category 0/0), but the differences were not statistically significant after adjustment for other factors including smoking habits. The presence of irregular (but not rounded) small shadows was associated with an impairment in respiratory function averaging about 190 ml deficits in both FEV1 and FVC. These deficits were not explicable in terms of the men's ages, body sizes, and smoking habits and they were in addition to the lung function losses attributable to the miners' dust exposure as such. It is concluded that the presence and profusion of small irregular opacities should be taken into consideration when assessing the severity of coalworkers' simple pneumoconiosis. 相似文献
4.
A. L. Rickards †‡ J. E. Walstab †‡ R. A. Wright-Rossi † J. Simpson† D. S. Reddihough†‡ 《Child: care, health and development》2009,35(5):593-602
Introduction There is debate about the type and intensity of early childhood intervention that is most helpful for children with developmental problems. The aim of the study was to determine whether a home‐based programme provided over 12 months resulted in sustained improvement in development and behaviour 12 months after the intervention ceased. The characteristics of the children and families who benefited most from the intervention were also studied. Method Randomized controlled trial. Participants A total of 59 children, aged 3–5 years, attending two early childhood intervention centres in Melbourne, Australia. Intervention Half of the subjects received an additional home‐based programme consisting of 40 weekly visits. Main outcome measures Bayley Scales of Infant Development and Wechsler Preschool and Primary Scale of Intelligence Revised, Preschool Behaviour Checklist, Bayley Behaviour Rating Scale and Behaviour Screening Questionnaire. All tests administered pre‐intervention, following the intervention and 12 months later. Secondary outcome measures Family stress, support and empowerment. Results Fifty‐four children completed the assessments 12 months after conclusion of the intervention. Compared with the control group, improvement in aspects of cognitive development in the children who received the extra intervention was sustained 1 year later (P= 0.007) while significant behavioural differences post intervention were not. Analyses of the data by the Reliable Change Index indicated improvement of clinical significance occurred in non‐verbal areas. In contrast to the control group who deteriorated, language skills in the intervention group remained stable. Improvements were significantly associated with higher stress in the families. Conclusion Improvements following the provision of a home‐based programme to preschool children with developmental disabilities were sustained 1 year later. Children from highly stressed families appeared to benefit most, reinforcing the importance of involving families in early childhood intervention programmes. 相似文献
5.
6.
The vascularity of 49 renal masses (26 malignant and 23 benign lesions) was investigated with duplex Doppler ultrasound. Doppler signals obtained at the margins of renal masses were defined as "tumor signals" when the Doppler-shifted frequency of the lesion exceeded the frequency shift in the ipsilateral main renal artery. These exceeded 2.5 kHz with a 3-MHz insonating frequency. Among the 26 renal masses that subsequently proved to be malignant, tumor signals were obtained in 15 of 18 (83%) untreated renal cell carcinomas, in three of four Wilms tumors, and in two patients with metastases to the kidney, but not in the one patient with lymphoma. None of the 23 benign renal masses demonstrated tumor signals. Tumor vascularity in malignant lesions gives rise to abnormal, high-velocity, Doppler-shifted signals that can help in the differential diagnosis of renal masses. 相似文献
7.
Detection of reactive oxygen species (ROS) and apoptosis in human fragmented embryos 总被引:8,自引:2,他引:8
Yang HW; Hwang KJ; Kwon HC; Kim HS; Choi KW; Oh KS 《Human reproduction (Oxford, England)》1998,13(4):998-1002
In human in-vitro fertilization (IVF)-embryo transfer, the in-vitro culture
environment differs from in-vivo conditions in that the oxygen
concentration is higher, and in such conditions the mouse embryos show a
higher concentration of reactive oxygen species (ROS) in simple culture
media. ROS are believed to cause damage to cell membranes and DNA
fragmentation in somatic cells. This study was conducted to ascertain the
level of H2O2 concentration within embryos and the morphological features
of cell damage induced by H2O2. A total of 62 human oocytes and embryos (31
fragmented, 15 non-fragmented embryos, 16 unfertilized oocytes) was
obtained from the IVF-embryo transfer programme. The relative intensity of
H2O2 concentrations within embryos was measured using
2',7'-dichlorodihydrofluorescein diacetate by Quanti cell 500 fluorescence
imaging and DNA fragmentation was observed with transmission electron
microscopy and an in-situ apoptosis detection kit. The H2O2 concentrations
were significantly higher in fragmented embryos (72.21 +/- 9.62, mean +/-
SEM) compared to non-fragmented embryos (31.30 +/- 3.50, P < 0.05) and
unfertilized oocytes (30.75 +/- 2.67, P < 0.05). Apoptosis was observed
only in fragmented embryos, and was absent in non-fragmented embryos.
Electron microscopic findings confirmed apoptotic bodies and cytoplasmic
condensation in the fragmented blastomeres. We conclude that there is a
direct relationship between increased H2O2 concentration and apoptosis, and
that further studies should be undertaken to confirm these findings.
相似文献
8.
9.
Pathways to care for alcohol use disorders 总被引:1,自引:0,他引:1
10.
Spectroscopic data define the structures of the flagranones A (2), B (3) and C (4) from the nematode-trapping fungus Duddingtonia flagrans. These antibiotics are structurally related to the farnesylated cyclohexenoxides of the oligosporon group recently isolated from the nematode-trapping fungus Arthrobotrys oligospora, and show similar antimicrobial activity. 相似文献