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91.
OBJECTIVES: Firstly, to determine if attendance for second round mammography screening in those sent a tailored letter (that is, making reference to their screening history) is increased compared with those sent a standard letter; secondly, to investigate the acceptability of tailored letters. SETTING: North West Glasgow Breast Screening Centre. METHODS: A randomised controlled trial. RESULTS: Overall attendance was unrelated to whether the women were sent a tailored or standard letter; 60% of those sent the standard letter attended (922/1531) compared with 62% of those sent the tailored letter (956/1552) (chi 2 = 0.61, P = 0.4) (difference 2%; 95% confidence interval -2% to 5%). There were no significant differences in percentage attendance within each of the study subgroups: women who attended previously and received an all clear result, women who attended previously and received a false positive result, women who were invited previously and failed to attend, and women who were previously too young to be invited for screening. However, there was a statistically significant difference in percentage attendance between these four groups, independent of letter type (chi 2 = 510, P < 0.00001). Although women found the letters acceptable and understandable, they did not seem to pay close attention to the content. CONCLUSIONS: Tailoring invitation letters does not have a significant effect on uptake rates for breast screening and does not justify the additional workload required.  相似文献   
92.
Older radiation detection equipment used in Health Physics operations suffers from unreliable and outdated electronics, even when the radiation detectors, shielding, and mechanical components are still serviceable. Upgrading these systems through relatively simple interfaces to modern personal computers can provide a cost-effective solution to extend the life of these systems and provide state-of-the-art options for computer control and automation. This paper outlines the basic needs and requirements for this type of upgrade and describes three projects at University of Missouri--Columbia that have used this approach.  相似文献   
93.
Cytochrome P-450cam hydroxylates d-camphor, using molecular oxygen and reducing equivalents transferred via putidaredoxin. We constructed mutant genes in which Phe-350 of P-450cam was replaced by Leu, Tyr, or His by site-directed mutagenesis, expressed them in Escherichia coli, purified the mutant proteins, and compared their enzymic properties with those of the wild type P-450cam. NADH oxidation rate of the Tyr mutant in the reconstituted system with putidaredoxin and putidaredoxin reductase was similar to that of the wild type enzyme, while the Leu mutant and the His mutant showed 67% and 17% activity of that of the wild type, respectively. The affinities of these mutant proteins for camphor and the oxidized form of putidaredoxin were much the same as those of the wild type protein. Rate constants for the reduction reaction of P-450cam by reduced putidaredoxin, a physiological electron donor for P-450cam, of Tyr and His mutants were much the same as that of the wild type enzyme, whereas the Leu mutant showed approx. half that of the wild type. Thus, the aromatic ring of Phe-350 of P-450cam probably contributes to enhancing efficiency of the electron transfer yet does not seem to be essential for the reaction.  相似文献   
94.
The technique of accumulating preparation of the mucosa and "turned out sac" was used to show that levorin, a polyenic antibiotic in a concentration of 10(-6) M, lowered the transport rate and accumulation of glucose by the epithelial cells of the rat thin intestine under conditions of oxygenation. Suppression of the glucose transport in the first stages resulted in partial inhibition of the transmembrane transfer. It is suggested that levorin suppression of the glucose transport through the erythrocyte apical membrane in the thin intestine is associated with a decrease in the electrochemical gradient of Na+.  相似文献   
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Qualitative and quantitative characteristics of chronic pain syndrome and their possible use in assessing analgetic effects of treatment were studied in 16, 49, 26 and 17 patients with gastric ulcer, duodenal ulcer, chronic pancreatitis, chronic colitis, respectively. Pain was measured with the use of McHill's questionnaire modification and visual-verbal-analog scale. In addition to routine analysis of the data from the respondents, graphic mean profiles of pain for each group have been devised. There were differences in quantitative parameters of pain syndrome depending on nosological unity and profiles of patients. The questionnaire proved rather informative in evaluation and gradation of analgetic effects of therapeutic factors in ulcer patients.  相似文献   
98.
Heparin has been shown to decrease total vascular resistance while protamine stimulates endothelium-dependent vasodilation. This study was undertaken to determine whether heparin and/or protamine could enhance endothelium-derived relaxing factor (EDRF), as determined by nitric oxide (NO) production. Porcine carotid artery endothelial cells (PAECs) were seeded on multiwell plates, grown to confluence, and exposed to heparin (1-20 U/ml) or protamine (50-200 microg/ml) for 24 hours. With the addition of the NO synthase inhibitor, N(G)-monomethyl-L-arginine (NMMA), to heparin and/or protamine, the medium samples were collected in one hour. In a parallel clinical study, plasma samples were collected from patients undergoing cardiopulmonary bypass (CPB). The NO production was measured as reflected by the formation of nitrite (NO2-) and nitrate (NO3-), the stable end-metabolites of NO. NO production by PAECs was significantly increased by heparin > or = 5 U/ml or protamine > or = 50 microg/ml in a concentration-dependent manner. The increase of NO production was prevented by the addition of NMMA. In CPB patients, plasma NO2-/NO3- concentration was significantly increased after heparin administration compared to the preoperative value, at which time the mean plasma heparin level was 4.9+/-0.5 U/ml. Following slow protamine infusion, there was no significant difference in plasma NO2-/NO3- concentration compared to preoperative value. In conclusion NO production increases following exposure of PAECs to heparin and/or protamine. In patients, NO concentration significantly increased after heparin administration by IV bolus, but not with a slow infusion of protamine after CPB.  相似文献   
99.
OBJECTIVES: Herein we describe an additional case of myelolipoma of the adrenal gland, an uncommon tumor of the adrenal cortex, that had been incidentally discovered during abdominal US evaluation of the biliary tree. The clinical features, diagnosis and treatment of the condition are discussed. METHODS: Surgical treatment of the biliary tree and myelolipoma was performed through a Chevron transversal incision during the same surgical session. RESULTS: Surgery achieved good results and the postoperative course was unremarkable. CONCLUSIONS: Myelolipoma is a benign nonfunctioning tumor of the adrenal cortex comprised of adipose and hematopoietic tissue. It is usually asymptomatic and incidentally discovered during diagnostic evaluation for other pathologies. The diagnosis is made by US, CT and MRI. There is no agreement on whether surgical treatment is warranted.  相似文献   
100.
The Kinematic Stabilizer is a posterior-cruciate-substituting design of total knee replacement. We have reviewed 109 primary total knee replacements in 95 patients at a mean follow-up time of 12.7 years (10 to 14). We used survival analysis with failure defined as revision of the implant. This gave a cumulative survival rate of 95% (95% CI +/- 5%) at ten years and (87% +/- 10%) at 13 years. These results from an independent centre confirm the value of an established design of cemented total knee replacement and question the wisdom of the introduction of modifications and new designs without properly controlled trials.  相似文献   
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