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61.
62.
We examined whether timeline icons improved older and younger adults' comprehension of medication information. In Experiment 1, comprehension of instructions with the icon (icon/text format) and without the icon (text-only format) was assessed by questions about information that was (a) implicit in the text but depicted explicitly by the icon (total dose in a 24 hour period), (b) stated and depicted in the icon/text condition (medication dose and times), and (c) stated but not depicted by the icon (e.g., side effects). In a separate task, participants also recalled medication instructions (with or without the icon) after a study period. We found that questions about dose and time information were answered more quickly and accurately when the icon was present in the instructions. Notably, icon benefits were greater for information that was implicit rather than stated in the text. This finding suggests that icons can improve older and younger adults' comprehension by reducing the need to draw some inferences. The icon also reduced effective study time (study time per item recalled). In Experiment 2, icon benefits did not occur for a less integrated version of the timeline icon that, like the text, required participants to integrate dose and time information in order to identify the total daily dose. The integrated version of the icon again improved comprehension, as in Experiment 1, as well as drawing inferences from memory. These findings show that integrated timeline icons improved comprehension primarily by aiding the integration of dose and time information. These findings are discussed in terms of a situation model approach to comprehension. 相似文献
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64.
HS Hiemstra PA van Veelen NC Schloot A Geluk KE van Meijgaarden SJ Willemen JA Leunissen WE Benckhuijsen R Amons RR de Vries BO Roep TH Ottenhoff JW Drijfhout 《Canadian Metallurgical Quarterly》1998,161(8):4078-4082
Progress has recently been made in the use of synthetic peptide libraries for the identification of T cell-stimulating ligands. T cell epitopes identified from synthetic libraries are mimics of natural epitopes. Here we show how the mimicry epitopes obtained from synthetic peptide libraries enable unambiguous identification of natural T cell Ags. Synthetic peptide libraries were screened with Mycobacterium tuberculosis-reactive and -autoreactive T cell clones. In two cases, database homology searches with mimicry epitopes isolated from a dedicated synthetic peptide library allowed immediate identification of the natural antigenic protein. In two other cases, an amino acid pattern that reflected the epitope requirements of the T cell was determined by substitution and omission mixture analysis. Subsequently, the natural Ag was identified from databases using this refined pattern. This approach opens new perspectives for rapid and reliable Ag definition, representing a feasible alternative to the biochemical and genetic approaches described thus far. 相似文献
65.
BG Russell WE Moddeman JC Birkbeck SE Wright DS Millington RD Stevens KE Dombrowski 《Canadian Metallurgical Quarterly》1998,4(4):257-266
The stimulating effect of antiparkinsonian drugs, talipexole and bromocriptine, on the striatal postsynaptic dopamine receptors were studied by measuring contralateral rotational behavior in rats. The nigro-striatal dopamine system of rats was degenerated by unilateral injection of 6-hydroxydopamine (6-OHDA, 8 micrograms/rat) into substantia nigra. By subcutaneous administration, talipexole at 0.16 mg/kg and bromocriptine at 10.24 mg/kg induced significantly increased rotational behavior to the contralateral direction to the lesioned side. The onset of the effect was 30 min for talipexole and 90 min for bromocriptine. By intragastric administration, talipexole at 0.4 mg/kg and bromocriptine at 20.48 mg/kg significantly increased the rotational behavior, and the onset of the effect was 60 min for talipexole and 180 min for bromocriptine. Rotational behavior induced by talipexole was suppressed by a D2 antagonist, sulpiride (40 mg/kg, s.c.), but not by a D1 antagonist, SCH23390 (1 mg/kg, s.c.). In contrast, rotational behavior induced by bromocriptine was suppressed by both sulpiride and SCH23390. These results indicated that when the nigrostriatal dopaminergic functions are disrupted, talipexole stimulates the striatal postsynaptic dopamine receptors at much lower doses than bromocriptine. Also it was indicated that the stimulating effect of talipexole is solely mediated by dopamine D2 receptors, whereas the effect of bromocriptine is mediated by both D1 and D2 receptors. 相似文献
66.
We have examined the immunolocalization of beta 1-integrin during feather development in the spino-lumbar tract of the backskin from normal and scaleless chick embryos. beta 1-integrin appears during early feather development in three distinct phases which correspond to important developmental events. The first phase (5-5 1/2 days of incubation; Hamburger and Hamilton [H.H.] stage 27) represents the period prior to the formation of dermis. During this phase, beta 1-integrin antiserum labels mesenchymal cells located in the central region of the spino-lumbar tract where the initiation site for feather development is located. The second phase (5 1/2-7 1/2 days of incubation; H.H. stages 28-32) corresponds to the period during which dermis is formed. The cells that make up the dermis are readily distinguished by their lack of beta 1-integrin immunostaining. The third phase (7 1/2-10 days of incubation; H.H. stages 33-36) begins with the sudden appearance of beta 1-integrin in the central and lateral regions of the dermis. The pattern of beta 1-integrin immunostaining in scaleless backskin becomes different from that of normal backskin during this phase. In normal backskin the dermal condensations of feather germs are not labeled with the beta 1-integrin antiserum. This produces a heterogeneous immunostaining pattern very similar to the pattern seen for Type I collagen (Mauger et al. [1982] Dev. Biol. 94:93-105). In contrast, homogeneous immunostaining is observed in the dermis of scaleless backskin. The initial time of appearance, manner of appearance, and pattern of integrin expression in the third phase suggest that beta 1-integrin may be involved in the stabilization of the feather pattern. We also observed the appearance of beta 1-integrin on the epidermal basal cells during the time of feather follicle formation. The beta 1-integrin antiserum reacts strongly with the baso-lateral surfaces of normal basal cells, yet the basal surfaces of the scaleless basal cells are unstained. This lack of immunostaining along the basal surfaces of the scaleless basal cells may relate to the abnormal adhesion between the epidermis and dermis in scaleless backskin. 相似文献
67.
PURPOSE: In this study, we sought to determine the outcome of patients with ischemic colitis, comparing patients with segmental disease with those with total colonic ischemia. METHODS: Patients with the diagnosis of ischemic colitis over the past six years were selected and reviewed for demographics, presenting symptoms, diagnosis, and treatment. RESULTS: Forty-three consecutive patients with ischemic colitis were identified and were grouped into those with segmental ischemic colitis and total colonic ischemia. Mean age was 68.8 years; 28 of 43 patients (65 percent) were males. Diagnosis was established by colonoscopy in 31 of 43 patients (72 percent), whereas in the remainder, diagnosis was made in the operating room. Ischemic colitis developed in the hospital in 17 of 43 patients (40 percent) during admission for an unrelated illness. In 6 of 43 (14 percent) of these patients, ischemic colitis developed following surgery. Thirty-one of 43 patients (72 percent) were found to have segmental colitis; 11 of 31 patients (35 percent) were successfully managed nonoperatively. Segmental colitis was present in 31 of 43 patients (72 percent), and 12 of 31 (35 percent) of these patients were successfully managed nonoperatively. In the patients with segmental colitis who required surgery, the 30-day mortality rate was 22 percent. Among 12 of 17 patients (71 percent) with segmental ischemia treated by resection and stoma, 9 of 12 (75 percent) underwent eventual stoma closure. All 12 patients with total colonic ischemia required surgery, and 9 of 12 patients (75 percent) died. CONCLUSION: Ischemic colitis occurs commonly during an unrelated hospital admission and following previous surgery. Most patients treated by resection and stoma undergo stoma closure. Total colonic ischemia carries a worse prognosis than segmental colonic ischemia. 相似文献
68.
SB Christensen A Guider CJ Forster JG Gleason PE Bender JM Karpinski WE DeWolf MS Barnette DC Underwood DE Griswold LB Cieslinski M Burman S Bochnowicz RR Osborn CD Manning M Grous LM Hillegas JO Bartus MD Ryan DS Eggleston RC Haltiwanger TJ Torphy 《Canadian Metallurgical Quarterly》1998,41(6):821-835
Evaluation of a variety of PDE4 inhibitors in a series of cellular and in vivo assays suggested a strategy to improve the therapeutic index of PDE4 inhibitors by increasing their selectivity for the ability to inhibit PDE4 catalytic activity versus the ability to compete for high affinity [3H]rolipram-binding sites in the central nervous system. Use of this strategy led ultimately to the identification of cis-4-cyano-4-[3-(cyclopentyloxy)-4-methoxyphenyl]cyclohexane-1-carboxyl ic acid (1, SB 207499, Ariflo), a potent second-generation inhibitor of PDE4 with a decreased potential for side effects versus the archetypic first generation inhibitor, (R)-rolipram. 相似文献
69.
Platelet-activating factor (PAF) production is carefully controlled in inflammatory cells. The specific removal of arachidonate (AA) from 1-O-alkyl-2-arachidonoyl-sn-glycero-3-phosphocholine (GPC), thought to be mediated by CoA-independent transacylase (CoA-IT), is required to generate the PAF precursor 1-O-alkyl-2-lyso-GPC in human neutrophils. Exposure of A23187-stimulated human monocytes to the CoA-IT inhibitors SK&F 98625 and SK&F 45905 inhibited PAF formation (IC50s of 10 and 12 microM, respectively), indicating that these cells also need CoA-IT activity for PAF production. Because CoA-IT activity transfers arachidonate to a 2-lyso phospholipid substrate, its activity is obligated to an sn-2 acyl hydrolase to form the 2-lyso phospholipid substrate. SB 203347, an inhibitor of 14 kDa phospholipase A2 (PLA2), and AACOCF3, an inhibitor of 85 kDa PLA2, both inhibited AA release from A23187-stimulated human monocytes. However, AACOCF3 had no effect on A23187-induced PAF formation at concentrations as high as 3 microM. Further, depletion of 85 kDa PLA2 using antisense (SB 7111, 1 microM) had no effect on PAF production, indicating a lack of a role of 85 kDa PLA2 in PAF biosynthesis. Both SB 203347 and the 14 kDa PLA2 inhibitor scalaradial blocked PAF synthesis in monocytes (IC50s of 2 and 0.5 microM, respectively), suggesting a key role of 14 kDa PLA2 in this process. Further, A23187-stimulated monocytes produced two forms of PAF: 80% 1-O-alkyl-2-acetyl-GPC and 20% 1-acyl-2-acetyl-GPC, which were both equally inhibited by SB 203347. In contrast, inhibition of CoA-IT using SK&F 45905 (20 microM) had a greater effect on the production of 1-O-alkyl (-80%) than of 1-acyl (-14%) acetylated material. Finally, treatment of U937 cell membranes with exogenous human recombinant (rh) type II 14 kDa PLA2, but not rh 85 kDa PLA2, induced PAF production. Elimination of membrane CoA-IT activity by heat treatment impaired the ability of 14 kDa PLA2 to induce PAF formation. Taken together, these results suggest that a 14 kDa PLA2-like activity, and not 85 kDa PLA2, is coupled to monocyte CoA-IT-induced PAF production. 相似文献
70.
TDI is a new echocardiographic technique that calculates and displays color-coded myocardial velocity on-line. To determine the feasibility of endocardial velocity throughout the cardiac cycle as a means to quantify regional function, 20 normal subjects aged 30 +/- 5 years and 12 patients with heart disease aged 62 +/- 17 years were studied with a prototype TDI system. TDI M-mode images were acquired by using a multicolored velocity map (display range, -30 to 30 mm/sec; temporal resolution, 90 Hz). Color-coded velocity data were then converted to numeric values off-line at 50 msec intervals. Posterior wall velocities throughout the cardiac cycle by TDI were closely correlated with velocity calculations from the first derivative of routine digitized M-mode tracings (group mean r = 0.88 +/- 0.03, SEE = 7.0 +/- 1.1 mm/sec). Anteroseptal TDI color-coded systolic velocity occurred 164 +/- 84 msec from the onset of the electrocardiographic QRS compared with 203 +/- 33 msec in the posterior wall (P < 0.05) in normal subjects, consistent with normal electrical activation. Significant differences in systolic and diastolic posterior wall TDI velocity data were observed in patients with hypokinetic or akinetic segments assessed by independent routine study when compared with normal controls. Calculated systolic and early diastolic posterior wall TDI indexes correlated significantly with percentage of wall thickening. Of abnormal anteroseptal segments, TDI systolic time velocity integrals were significantly different than normal and correlated with percentage of wall thickening. TDI has potential to quantitatively assess regional left ventricular function. 相似文献