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991.
992.
Marshall Alison L. Bauman Adrian E. Owen Neville Booth Michael L. Crawford David Marcus Bess H. 《Annals of behavioral medicine》2003,25(3):194-202
Background: Intervention trials with self-selected participants have shown that mailed stage-targeted print materials can increase participation
in physical activity in the short term. We examined the effects of a mailed stage-targeted print intervention designed to
promote physical activity, in a random sample of adults living in a regional city.Method: Participants (n = 462, 40–60 years of age) were randomly allocated to an intervention in - 227) or control group (n - 235).
Measures included validated 2-week physical activity recall and stage of motivational readiness for physical activity. The
intervention consisted of a single mailing of a letter and full-color stage-targeted booklets (specific to precontemplation,
contemplation, preparation, and action/maintenance) 1 week postbaseline. Follow-up interviews were conducted at 2 and 6 months
postbaseline.Results: After 2 months, participants in the intervention group were significantly More likely to meet the current American College
of Sports Medicine/Centers for Disease Control and Prevention recommendation for sufficient physical activity than those in
the control group (adjusted odds ratio [OR] - 2.40; 95% confidence interval [CI] = 1.44–3.99). After 6 months, intervention
participants who reported receiving and reading the intervention materials were significantly more likely to be meeting the
sufficient physical activity criterion compared with the control group (adjusted OR = 2.03; 95% Cl = 1.16–3.56).Conclusions: The stage-targeted print intervention was effective in promoting short-term increases in physical activity and was most
effective for participants who recognized and used the materials. This low-cost, generalizable intervention has demonstrated
potential as a practical population-based physical activity promotion strategy. Further research is required before widespread
dissemination would be justified, as additional strategies may be required to ensure sustained change.
This project was supported by a National Heart Foundation of Australia Research Project Grant. David Crawford was supported
by a Nutrition Research fellowship from the National Heart Foundation. 相似文献
993.
994.
S Wu K Rodabaugh O Martinez-Maza J M Watson D S Silberstein C M Boyer W P Peters J B Weinberg J S Berek R C Bast 《American journal of obstetrics and gynecology》1992,166(3):997-1007
OBJECTIVE: We investigated whether monocyte-derived factors could stimulate the growth of ovarian cancer cells. STUDY DESIGN: Human peripheral blood monocytes or human monocyte-like cell lines THP-1 and U-937 were cultured with or without macrophage colony-stimulating factor, lipopolysaccharide, or phorbol myristate acetate. Culture supernatants or recombinant cytokines were assayed for growth stimulation of ovarian cancer cell lines by tritium-thymidine incorporation and direct cell counts followed by statistical analysis with Student t test. RESULTS: Conditioned medium from peripheral blood monocytes or from THP-1 or U-937 cells stimulated ovarian cancer cell growth. Interleukin-1 alpha, tumor necrosis factor-alpha, and interleukin-6 also stimulated ovarian cancer cell growth, whereas macrophage, granulocyte, and granulocyte-macrophage colony-stimulating factor did not. Concentrations of tumor necrosis factor, interleukin-1, and interleukin-6 in conditioned medium could not account for all the growth stimulation, and activity remained after neutralization of tumor necrosis factor, interleukin-1, and interleukin-6 with antibodies. CONCLUSIONS: Interleukin-1, interleukin-6, tumor necrosis factor, and additional monocyte factor(s) could provide paracrine growth stimulation when monocytes are attracted to ovarian cancers that produce macrophage colony-stimulating factor. 相似文献
995.
Michael F. Sarosdy 《World journal of urology》1997,15(2):103-106
Summary The BTA Test is an adjunctive test for the diagnosis and management of bladder cancer. For estimation of its potential in the management of patients with transitional-cell cancer (TCC) a review of published results was undertaken. Three prospective studies were analyzed, in which a total of 699 patients with a history of TCC were enrolled. The BTA Test was performed on voided urine and compared with either voided-urine or bladder-wash cytologic analysis in a blinded fashion. In all three studies the sensitivity of the BTA Test was more than double that of cytology, irrespective of whether the cytologic analysis was performed on voided or bladder-wash samples. The third study also included an additional 225 patients undergoing evaluation for hematuria, and TCC was found in 67 cases. The BTA Test detected 70% of these tumors, whereas cytology detected only 25%. The BTA Test is a simple, rapid test that can diagnose a substantial percentage of patients having new or recurrent bladder TCC. Its complete role in the management of such patients remains to be defined. 相似文献
996.
G J Michael 《Australasian physical & engineering sciences in medicine / supported by the Australasian College of Physical Scientists in Medicine and the Australasian Association of Physical Sciences in Medicine》1992,15(2):75-87
A new dual-energy x-ray CT algorithm is presented which makes use of both pre- and post-reconstruction data in an iterative manner to achieve accurate beam hardening correction and decomposition into basis materials. The technique does not require a calibration phantom and also does not require accurate estimation of the effective energies of the polyenergetic x-ray beams. It does however, require a knowledge of the incident x-ray spectra. For the situation where the incident spectra are unknown, a method is given whereby sufficiently accurate approximations to the spectra can be determined from attenuation measurements. Decomposition into basis materials makes use of spatial and energy information and an 'a priori' knowledge of the composition and attenuating properties of various tissue types. Any total number of basis materials may be used within the limitation that a subset containing a maximum of three materials is used for any individual pixel. Results of a computer simulation show that the algorithm produces accurate measurements of the concentrations of both high and low atomic number materials such as bone mineral, collagen, fat and air. However the results of a phantom study show that the measurement of the concentrations of low atomic number basis materials may be subject to systematic errors arising from uncertainties in the published values of linear attenuation coefficients. 相似文献
997.
Juha-Matti Savola Michael Hill Mia Engstrom Hannele Merivuori Siegfried Wurster Steven G McGuire Susan H Fox Alan R Crossman Jonathan M Brotchie 《Movement disorders》2003,18(8):872-883
Previous studies in the MPTP-lesioned primate model of Parkinson's disease have demonstrated that alpha(2) adrenergic receptor antagonists such as idazoxan, rauwolscine, and yohimbine can alleviate L-dopa-induced dyskinesia and, in the case of idazoxan, enhance the duration of anti-parkinsonian action of L-dopa. Here we describe a novel alpha(2) antagonist, fipamezole (JP-1730), which has high affinity at human alpha(2A) (K(i), 9.2 nM), alpha(2B) (17 nM), and alpha(2C) (55 nM) receptors. In functional assays, the potent antagonist properties of JP-1730 were demonstrated by its ability to reduce adrenaline-induced (35)S-GTPgammaS binding with K(B) values of 8.4 nM, 16 nM, 4.7 nM at human alpha(2A), alpha(2B), and alpha(2C) receptors, respectively. Assessment of the ability of JP-1730 to bind to a range of 30 other binding sites showed that JP-1730 also had moderate affinity at histamine H1 and H3 receptors and the serotonin (5-HT) transporter (IC(50) 100 nM to 1 microM). In the MPTP-lesioned marmoset, JP-1730 (10 mg/kg) significantly reduced L-dopa-induced dyskinesia without compromising the anti-parkinsonian action of L-dopa. The duration of action of the combination of L-dopa and JP-1730 (10 mg/kg) was 66% greater than that of L-dopa alone. These data suggest that JP-1730 is a potent alpha(2) adrenergic receptor antagonist with potential as an anti-dyskinetic agent in the treatment of Parkinson's disease. 相似文献
998.
Irwin S. Johnsrude William M. Bogey Jr Michael D. Tripp 《Cardiovascular and interventional radiology》1994,17(6):336-338
Discovery of a postlumbosacral discectomy fistula between the right iliac artery and vein was obscured by an associated severe stricture of the infrarenal inferior vena cava in a 49-year-old man. During venous stenting for treatment of peripheral edema, the fistula was suspected because of faint pulsatile right iliac vein flow and increased O2 saturation of the venous blood. The suspicion was confirmed on subsequent iliac arteriography. Surgical closure of the fistula with arterial interposition grafting was then performed. The patient improved substantially. 相似文献
999.
Mikael Bisrat Eva Karin Anderberg Michael I. Barnett Christer Nystr m 《International journal of pharmaceutics》1992,80(1-3):191-201
The dissolution rates of sparingly soluble, fine particulate, suspended drugs have been studied using a Coulter Counter Model TAII. For two sieve fractions of oxazepam the dissolution rates were monitored in media with varying viscosities brought about by the addition of glycerol, while for griseofulvin the change in the medium's viscosity was induced by changing the temperature. By calculating the dissolution rate, and compensating for differences in particle surface area and media solubility, it was shown that the dissolution rate was diffusion controlled. After additional normalization for the diffusion coefficient, it was suggested that the so-called apparent diffusional distance decreased substantially with particle size. The effect of particle size was more limited above approx. 15 μm. 相似文献
1000.