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91.
92.
The concept of cardiac reconditioning centers for the prevention and rehabilitation of coronary patients has been tremendously successful in Germany over the past 20 years. At least 40 such centers are located throughout the country. Physicians, nurses, and physical therapists work closely together in the various facets of the rehabilitation process. The financial backing for these facilities is primarily through governmental and regional insurance companies, whose officials are apparently convinced that in the long run supporting preventive measures is financially sound. Objective data supporting their convictions come from studies such as that of Brusis, who showed that such as that of 1,500 employees was diminished by nearly 70 percent during a two-year period after cardiac reconditioning, as compared to a similar time period before the rehabilitation experience. Subjective benefits, which are extremely difficult to quantitate in meaningful terms, were nonetheless expressed by nearly all the patients with whom I conversed. Perhaps they have experienced the same feelings that Mark Twain did when he observed that "all frets and worries and chafings sank to sleep in the presence of the benignant serenity of the Alps; the Great Spirit of the Mountains breathed his own peace upon their hurt minds and sore hearts and healed them."  相似文献   
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Effects of etoposide (VP-16) and cytosine arabinoside (Ara-C) on the cell cycle of HL-60 and THP-1 cells were studied by flow cytometry using the bromodeoxyuridine (BrdU)/DNA assay technique to investigate the efficacy of VP-16 for monocytic leukemia cells. VP-16 inhibited the proliferation of THP-1 cells more strongly than that of HL-60 cells at any concentrations used at 24 and 48 hr. VP-16 arrested HL-60 and THP-1 cells in the G2/M phase and reduced them in the G0/G1 and early S phase at higher concentrations. There was no significant difference in the percentage of G2/M phase cells at the same concentration between both cells. However, reduction in the G0/G1 and early S phase cells was more marked in THP-1 than HL-60 cells significantly. On the other hand, Ara-C perturbed the cell cycle of HL-60 cells more than that of THP-1 cells at 24 and 48 hr. These results suggest that the effects of VP-16 on the cell cycle may be more intense in THP-1 than HL-60 cells, and support the efficacy of VP-16 for treating monocytic leukemia in vivo.  相似文献   
95.
In 1936, when Eila Hopper Ross (nee Hopper) was putting the final stroke of paint on her six-foot oil canvas of a life model at the Ontario College of Art, she had not dreamed that in the year to follow she would embark upon a life's career of anatomical study and attention to intricate detail in her own work as a medical illustrator. Though she had early aspirations herself of going into medicine--having been raised in a medical environment with her father, Dr. David Alexander Hopper, regularly receiving pharmaceutical literature with impressive illustrations--Hopper Ross was not aware of medical illustration as a profession. It was Maria Wishart, then director of the Medical Art Service Unit at the University of Toronto, who saw Hopper Ross' final exhibition at the Ontario College of Art and recommended she consider a career in medical art. As a result, Hopper Ross studied for two years (1937-1939) in the Department of Art as Applied to Medicine at Johns Hopkins University in Baltimore, Maryland under the direction of Professor Max Br?del.  相似文献   
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Neutrophils expressing cyclooxygenase-2 (COX-2) extensively infiltrate maternal blood vessels in preeclampsia, associated with vascular inflammation. Because pregnancy neutrophils also express protease-activated receptor 1 (PAR-1, F2R thrombin receptor), which they do not in non-pregnant subjects, they can be activated by proteases. We tested the hypothesis that aspirin at a dose sufficient to inhibit COX-2 would reduce inflammatory responses in preeclampsia neutrophils. Neutrophils were isolated from normal pregnant and preeclamptic women at approximately 30 weeks’ gestation. Normal pregnancy neutrophils were treated with elastase, a protease elevated in preeclampsia, or elastase plus aspirin to inhibit COX-2, or elastase plus pinane thromboxane, a biologically active structural analog of thromboxane and a thromboxane synthase inhibitor. Preeclamptic pregnancy neutrophils were treated with the same doses of aspirin or pinane thromboxane. Confocal microscopy with immunofluorescence staining was used to determine the cellular localization of the p65 subunit of nuclear factor-kappa B (NF-κB) and media concentrations of thromboxane were measured to evaluate the inflammatory response. In untreated neutrophils of normal pregnant women, p65 was localized to the cytosol. Upon stimulation with elastase, p65 translocated from the cytosol to the nucleus coincident with increased thromboxane production. When neutrophils were co-treated with aspirin or pinane thromboxane, elastase was not able to cause nuclear translocation of p65 or increase thromboxane. In untreated neutrophils of preeclamptic women, the p65 subunit was present in the nucleus and thromboxane production was elevated, but when preeclamptic neutrophils were treated with aspirin or pinane thromboxane, p65 was cleared from the nucleus and returned to the cytosol along with decreased thromboxane production. These findings suggest that COX-2 is a downstream mediator of PAR-1 and demonstrate that PAR-1- mediated inflammation can be inhibited by aspirin. Given the extensive and ubiquitous expression of PAR-1 and COX-2 in preeclamptic women, consideration should be given to treating women with preeclampsia using a dose of aspirin sufficient to inhibit COX-2.  相似文献   
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99.

Objective

To assess the differential effectiveness of two methods of disseminating a smoking cessation programme to public hospital antenatal clinics.

Design

Group randomised trial.

Setting

22 antenatal clinics in New South Wales, Australia.

Intervention

Clinics were allocated to a simple dissemination (SD) condition (11 clinics) which received a mail‐out of programme resources or to an intensive dissemination (ID) condition (11 clinics) which included the mail‐out plus feedback, training, and ongoing support with midwife facilitator.

Main outcome measures

Independent cross sectional surveys of women on a second or subsequent visit undertaken pre‐dissemination and 18 months after dissemination. Outcomes were: (1) levels of smoking status assessment by clinic staff; (2) proportion of women identifying as having been smokers at their first visit who reported receiving cessation advice; (3) proportion of these women who had quit (self report and expired air carbon monoxide (CO)); and (4) smoking prevalence among all women (self report and CO).

Subjects

5849 women pre‐dissemination (2374 SD, 3475 ID) and weighted sample of 5145 women post‐dissemination (2302 SD, 2843 ID).

Results

There were no significant differences between the groups on change on any outcome. Change in either group was minimal. In the post‐dissemination survey, the cessation proportions were 6.4% (SD) and 10.5% (ID).

Conclusions

Relatively modest strategies for encouraging incorporation of smoking cessation activities into antenatal care were not effective in the long term. Alternative strategies should be implemented and evaluated. The findings reinforce the importance of a whole population approach to tobacco control.  相似文献   
100.
D.J. Walsh  S. Rostami 《Polymer》1985,26(3):418-422
Flory's equation-of-state theory has been used to predict the lower critical solution temperature behaviour of polymer—polymer mixtures. The spinodal phase boundary of numbers of high molecular weight polymer mixtures have been previously simulated using this theory. In this paper a procedure for simultaneous predictions of the binodal and the spinodal curves by equating the chemical potential of each component in the mixture is presented. The method is tested for five different mixtures. The effects of the binary and pure component state parameters on the simulated curves are discussed and the simulated phase diagrams are compared with the experimental cloud point curves. It is found that in most cases the results are more consistent with the cloud point curve being closer to the spinodal curve than the binodal.  相似文献   
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