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排序方式: 共有1261条查询结果,搜索用时 15 毫秒
1.
2.
Sonoelasticity imaging of prostate cancer: in vitro results 总被引:2,自引:0,他引:2
3.
Screening for early ovarian cancer 总被引:5,自引:0,他引:5
4.
Physical activity and quality of life in older adults: Influence of health status and self-efficacy 总被引:2,自引:1,他引:1
Edward McAuley Ph.D. James F. Konopack Ed.M. Robert W. Motl Ph.D. Katherine S. Morris B.A. Shawna E. Doerksen M.S. Karl R. Rosengren Ph.D. 《Annals of behavioral medicine》2006,31(1):99-103
Background: Physical activity has been positively linked to quality of life (QOL) in older adults. Measures of health status and global
well-being represent common methods of assessing QOL outcomes, yet little has been done to determine the nature of the relationship
of these outcomes with physical activity.Purpose: We examined the roles played by physical activity, health status, and self-efficacy in global QOL (satisfaction with life)
in a sample of older Black and White women.Method: Participants (N = 249, M age = 68.12 years) completed multiple indicators of physical activity, self-efficacy, health status,
and QOL at baseline of a 24-month prospective trial. Structural equation modeling examined the fit of 3 models of the physical
activity and QOL relationship.Results: Analyses indicated that relationships between physical activity and QOL, self-efficacy and QOL were all indirect. Specifically,
physical activity influenced self-efficacy and QOL through physical and mental health status, which in turn influenced global
QOL.Conclusions: Our findings support a social cognitives model of physical activity’s relationship with QOL. Subsequent tests of hypothesized
relationships across time are recommended.
Funding for this study was provided by the National Institute on Aging (Grant AG 20118). We extend our sincere appreciation
to April Bell for all of her efforts on this project. 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.
Charles H Hillman Elizabeth T Hsiao-Wecksler Karl S Rosengren 《International journal of psychophysiology》2005,55(1):45-49
Postural and eye-blink reactions to acoustic startle probes were examined in 24 volunteers, who completed two blocked conditions (baseline, startle). A postural reaction during the startle condition demonstrated a reflexive movement in the anterior-posterior direction, which was not observed during the baseline condition. This reflexive response was positively associated with the eye-blink reflex, such that larger blink magnitude related to greater posterior movement. These findings were not observed for postural movements in the medial-lateral direction. The results suggest that a measurable postural reaction may be observed following a startling acoustic stimulus, which may reflect generalized bodily flexion associated with a preparatory behavioral response. 相似文献
8.
Spermidine/spermine-N1-acetyltransferase activity in isoprenaline-stimulated rat salivary glands 总被引:1,自引:0,他引:1
J Ekstr?m B M?nsson B O Nilsson E Rosengren G Tobin 《Acta physiologica Scandinavica》1989,135(3):249-254
In parotid, sublingual and submaxillary glands stimulated by continuous intravenous infusion of isoprenaline at various doses for 3 h, the concentrations of the polyamines putrescine, spermidine, spermine and N1-acetylspermidine as well as the activities of ornithine decarboxylase and spermidine/spermine-N1-acetyltransferase were determined. Ornithine decarboxylase is the enzyme that catalyses the formation of putrescine from ornithine. The most striking effect was observed in parotid glands. Here, the beta-adrenergic agonist increased the activity of spermidine/spermine-N1-acetyltransferase markedly, but only slightly (if at all) that of ornithine decarboxylase. It also increased the concentrations of N1-acetylspermidine and putrescine markedly. The result obtained in this gland indicates interconversion of higher polyamines to putrescine. 相似文献
9.
10.
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