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排序方式: 共有1106条查询结果,搜索用时 46 毫秒
81.
Aimée E van Dijk Manon van Eijsden Karien Stronks Reinoud JBJ Gemke Tanja GM Vrijkotte 《BMC public health》2010,10(1):251
Background
Recent evidence, both animal and human, suggests that modifiable factors during fetal and infant development predispose for cardiovascular disease in adult life and that they may become possible future targets for prevention. One of these factors is maternal psychosocial stress, but so far, few prospective studies have been able to investigate the longer-term effects of stress in detail, i.e. effects in childhood. Therefore, our general aim is to study whether prenatal maternal psychosocial stress is associated with an adverse cardio-metabolic risk profile in the child at age five. 相似文献82.
The diffusion of magnetic resonance imaging scanners in a changing U.S. health care environment. 总被引:1,自引:0,他引:1
B D Hillman C R Neu J D Winkler J Aroesty R A Rettig A P Williams 《International journal of technology assessment in health care》1987,3(4):545-559
Technological aspects and early clinical experiences are arousing great enthusiasm over magnetic resonance imaging (MRI). However, influences such as regulation, reimbursement, and increasing competition also are playing important roles in determining the diffusion of this new technology. Of these considerations, competition among providers seems the most important. Competition related to MRI is manifested as direct competition over MRI services, using MRI to improve a provider's strategic position and competition among specialties. In making decisions concerning MRI acquisition and operation, providers are drawing upon their experiences with computed tomography (CT) to help them determine when would be the best time for acquisition, how to decide whether acquisition is appropriate, and how best to acquire, operate, and market the technology. 相似文献
83.
84.
Front D; Ioselevsky G; Frenkel A; Even-Sapir E; Israel O; Kolodny GM; Feinsud M 《Radiology》1987,164(1):93-96
A single photon emission computed tomographic method was designed for the measurement of radiopharmaceutical uptake in brain tumors. Results of phantom studies showed a correlation coefficient of .99 when measured volume was compared with actual volume. The correlation coefficient for measured radioactivity concentration compared with the actual concentration was .97. In 13 meningiomas the correlation between in vivo SPECT measurements of uptake and in vitro measurements in samples of the same tumors removed surgically was .84; when two tumors that contained regions of necrosis and fibrosis were excluded it was .93. This method can be used for in vivo quantitative assessment of pharmacokinetics of labeled drug uptake in human brain tumors. 相似文献
85.
86.
The effect of bilateral surgical deafferentation of the baroreceptors in the aortic arch and carotid sinus on experimentally induced water intake was investigated in rats. Drinking was induced by subcutaneous administration of one of the following agents: hypertonic saline, polyethylene glycol, isoproterenol and angiotensin II, or by 18 h of water deprivation. Hypertonic saline-induced drinking was significantly attenuated after bilateral denervation of either the aortic arch plus the carotid sinus or the aortic arch alone. However, this diminished response disappeared when hypertonic saline was given in subsequent tests. The initial drinking deficit following hypertonic saline was independent of the time elapsed since the animals had undergone surgery. All other thirst challenges tested resulted in water intake that was not statistically different from sham-operated control groups. It is concluded that aortic baroreceptor deafferentation initially results in a diminished drinking response following hypertonic saline, possibly due to interruption of afferent information originating in osmosensitive areas in the aortic arch. A role of arterial baroreceptors in the regulation of non-osmotically induced water intake is not supported by the present data. 相似文献
87.
Cardiovascular effects of microinjections of angiotensin II into the nucleus tractus solitarii 总被引:2,自引:0,他引:2
The role of the angiotensin II system within the nucleus tractus solitarii (NTS) in central cardiovascular control was investigated by local microinjections of angiotensin II and the angiotensin II receptor antagonist saralasin. Microinjections of 1 ng angiotensin II into the NTS resulted in a monophasic depressor response (-7.3 +/- 1.7 mm Hg), while higher doses were characterized by a biphasic response, with an initial decrease followed by a subsequent increase in blood pressure (10 ng: -4.7 +/- 1.3/+7.9 +/- 1.1 and 100 ng: -2.4 +/- 1.2/+7.5 +/- 1.2 mm Hg). Heart rate decreased significantly following microinjections of 1 and 10 ng angiotensin II (-27 +/- 5.0 and -15 +/- 5.9 bpm), while with 100 ng angiotensin II there was no significant effect on heart rate. Prior i.v. administration of atropine (1 mg/kg) abolished the bradycardia, but did not significantly affect the blood pressure response. Microinjections of saralasin into the NTS elicited a dose-dependent pressor response (10 ng: 6.0 +/- 1.5 mm Hg; 100 ng: 16.8 +/- 3.4 mm Hg) and tachycardia (10 ng: 5 +/- 3.2 bpm; 100 ng: 17 +/- 4.4 bpm). Our data support the hypothesis that angiotensin II acts on specific receptors within the NTS to modulate peripheral cardiovascular responses. The cardiovascular effects elicited by microinjections of the peptide exhibit complicated dose-response relationships. The effects on heart rate, but not on blood pressure, appear to be mediated by parasympathetic activation. 相似文献
88.
89.
90.
Canthaxanthin induces apoptosis in human cancer cell lines 总被引:3,自引:1,他引:2
Palozza P; Maggiano N; Calviello G; Lanza P; Piccioni E; Ranelletti FO; Bartoli GM 《Carcinogenesis》1998,19(2):373-376
To investigate the possibility that canthaxanthin inhibits cancer cell
growth by inducing apoptosis, human WiDr colon adenocarcinoma and SK- MEL-2
melanoma cells were treated with two different doses of the carotenoid for
48 h. Canthaxanthin was incorporated and/or associated to cells. The
treatment with the carotenoid caused growth inhibition in both cell types.
Concomitantly, apoptosis was induced. Increasing time of exposure and
carotenoid concentration, this effect was more pronounced. At 48 h, the
percentages of apoptotic cells were 13 and 15, using 1 microM
canthaxanthin, and 18 and 20, using 10 microM canthaxanthin in WiDr and
SK-MEL-2 cells, respectively. This study represents the first demonstration
that canthaxanthin is able to induce apoptosis in tumour cells.
相似文献