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981.
982.
Effective Patient Teaching (EPT), a course designed to improve health professionals' and health professions students' teaching skills, reliably produces gains in participants' skills when presented by its developers. The objective of this dissemination research study was to investigate whether, using a 'training of trainers' approach, seven nurses with staff development responsibilities in five different sites could teach EPT with similar effectiveness. The evaluation included pre- and post-course analysis of audiotaped patient education sessions conducted by 48 health professional participants who took EPT from one of the trainers in their home institutions. Post-course participant satisfaction surveys were also administered. EPT resulted in teaching skill improvements in four of five sites, and overall teaching skills scores improved significantly (P < 0.01). EPT can improve participants' teaching skills when taught by health professional trainers with staff development responsibilities who have recently received EPT training.  相似文献   
983.
Neurotrophins are a family of highly conserved proteins that affect the development and maintenance of distinct neuronal populations. Neurotrophins exist in vivo as homodimers, but we show that neurotrophins can exist as heterodimers in vitro and are pluripotent, being able to bind and to activate different Trk tyrosine kinase receptors as well as promote neuronal differentiation in PC12 cells as effectively as wild type homodimers. These asymmetric neurotrophin dimers allow unique characterization of neurotrophin structure-function relationships with Trk receptors. The chimeric Trk activities of these heterodimers suggest an alternative model of neurotrophin-Trk receptor activation in which the critical Trk-interacting elements may be attributed to a single protomer.  相似文献   
984.
985.
Indium-111 (111In) and technetium-99m (99Tcm) Stealth liposomes were compared with 111In- and 99Tcm-labelled white blood cells (WBC) in experimental infection in a rabbit model. Preformed polyethylene glycol-coated liposomes and separated WBC were radiolabelled with either 111In-oxine or 99Tcm-hexamethylpropyleneamine oxime (99TcM-HMPAO). After the intravenous administration of one of the four radiopharmaceuticals to rabbits with focal Staphylococcus aureus infection, scintigraphic images were recorded at various time points post-injection and the biodistribution of the radiopharmaceuticals was determined. At 4 h post-injection, uptake of 111In-WBC in the abscess was significantly higher than that of the three other products. AT later time points, 111In-WBC, 111In-liposome and 99Tcm-liposome uptake in the abscess were similar. In contrast, a 20 h post-injection, uptake of 99Tcm-WBC was significantly lower. The abscess-to-background ratios showed a similar pattern to the absolute abscess uptake: initial high values for 111In-WBC, a more gradual increase over time of the liposome preparations to the level of 111In-WBC and persistently low values for 99Tcm-WBC. Clearance from the blood of both labelled WBC preparations was significantly faster and splenic uptake significantly higher compared with those of the labelled liposomes. In conclusion, given the similar in vivo characteristics of labelled liposomes and labelled WBC, labelled liposomes may be an attractive replacement for labelled WBC, providing a continuously available, high-quality, 99Tcm-labelled radiopharmaceutical that can be prepared easily without any need to handle blood.  相似文献   
986.
INTRODUCTION: Iodine containing agents are used as radiologic contrast media and for the treatment of upper respiratory infections, heart diseases, thyreotoxicosis, erythema nodosum and wound disinfection. Vegetating iododerma is a rare but severe cutaneous side effect. CASE STUDY: We report a case of iododerma in a 84 year-old patient, presenting iododerma 14 months after introduction of amiodarone treatment. Despite cessation of this therapy, an important exacerbation of the skin lesions was observed 3 months later. Therapy with cyclosporine produced a marked regression of the skin lesions. DISCUSSION: We are aware of only one other reported case of amiodarone induced iododerma, which occurred after 2 years of therapy. Our patient was also exposed to iodine containing radiographic contrast media 1 and 18 years before onset of the actual skin disease. A sensitizing role of these injections is possible, but we feel that they did not directly induce the skin eruption as all reported cases occurred within a few days after exposure. CONCLUSION: Amiodarone can exceptionally be responsible for severe iododerma. Cyclosporine is, according to our experience, a valuable therapeutic option.  相似文献   
987.
There is little information on the microbiology of periapical lesions, and no data on the residual microbial flora in the periapex, if any, after apicoectomy procedures. Hence, 64 patients treated by apicoectomy procedures were prospectively studied to assess the bacterial flora in the periapex and to evaluate the residual bacteria in postoperative apicoectomy sites. Of the 64 lesions studied, 14 (22%) were sterile and 50 (78%) yielded bacteria preoperatively. Bacteria could be recovered from 28 (56%) of the latter lesions after apicoectomy and curettage. A total of 105 bacterial strains was isolated from 50 lesions, yielding a range of 1-4 (mean 2.1) species per sample. The isolates comprised 84 (80%) facultative anaerobes and 21 (20%) strict anaerobes. A polymicrobial growth was obtained from 39 lesions whilst 11 lesions yielded pure cultures. On detailed microbiological analyses of 29 lesions, 40% of the isolates were identified as alpha-haemolytic streptococci, half of which were Streptococcus sanguis; anaerobic streptococci were the predominant anaerobes. None of the organisms or group(s) of organisms emerged as recalcitrant colonisers which were difficult to dislodge after surgical debridement. These data indicate that the majority of periapical lesions harbour a variety of flora which cannot be eradicated despite thorough apicoectomy procedures.  相似文献   
988.
It is unclear whether the age-associated reduction in baroreflex sensitivity is modifiable by exercise training. The effects of aerobic exercise training and yoga, a non-aerobic control intervention, on the baroreflex of elderly persons was determined. Baroreflex sensitivity was quantified by the alpha-index, at high frequency (HF; 0.15-0.35 Hz, reflecting parasympathetic activity) and mid-frequency (MF; 0.05-0.15 Hz, reflecting sympathetic activity as well), derived from spectral and cross-spectral analysis of spontaneous fluctuations in heart rate and blood pressure. Twenty-six (10 women) sedentary, healthy, normotensive elderly (mean 68 years, range 62-81 years) subjects were studied. Fourteen (4 women) of the sedentary elderly subjects completed 6 weeks of aerobic training, while the other 12 (6 women) subjects completed 6 weeks of yoga. Heart rate decreased following yoga (69 +/- 8 vs. 61 +/- 7 min-1, P < 0.05) but not aerobic training (66 +/- 8 vs. 63 +/- 9 min-1, P = 0.29). VO2 max increased by 11% following yoga (P < 0.01) and by 24% following aerobic training (P < 0.01). No significant change in alpha MF (6.5 +/- 3.5 vs. 6.2 +/- 3.0 ms mmHg-1, P = 0.69) or alpha HF (8.5 +/- 4.7 vs. 8.9 +/- 3.5 ms mmHg-1, P = 0.65) occurred after aerobic training. Following yoga, alpha HF (8.0 +/- 3.6 vs. 11.5 +/- 5.2 ms mmHg-1, P < 0.01) but not alpha MF (6.5 +/- 3.0 vs. 7.6 +/- 2.8 ms mmHg-1, P = 0.29) increased. Short-duration aerobic training does not modify the alpha-index at alpha MF or alpha HF in healthy normotensive elderly subjects. alpha HF but not alpha MF increased following yoga, suggesting that these parameters are measuring distinct aspects of the baroreflex that are separately modifiable.  相似文献   
989.
PURPOSE: This study was undertaken to determine the effect of a bone graft in the piriform aperture on the nasal deformity and orthodontic treatment of the cleft side teeth in isolated cleft lip patients. PATIENTS AND METHODS: All primary cleft lip repair was done 3 months after birth. Nine patients, four female and five male, with a mean age of 12.5 years (range, 8.2 to 24.8 years) and with a repaired cleft lip, were bone grafted between 1992 and 1996. The mean postoperative period was 2 years (range, 1 to 4 years). An iliac crest bone graft was placed in the piriform aperture deformity on the side of the cleft lip. The improvement in the nasal symmetry and angulation of the cleft side teeth were evaluated. The eight growing cleft lip patients (mean age, 11 years; range, 9 to 13 years) were compared with a control group of eight healthy growing children (mean age, 11 years; range, 9 to 13 years). The improvement of nasal symmetry was measured by the formula of the lobule portion of the columella index preoperatively and postoperatively. RESULTS: The mean lobule portion of the columella index preoperatively was 41.8% (SD, 4.4%; SE of Mean, 1.5%) and postoperatively was 44.2% (SD, 4.9%; SE of Mean, 1.6%) (P > .006, t-test for paired samples). The angulation of the cleft side teeth was improved by orthodontic treatment. CONCLUSION: Bone grafting the piriform aperture deformity results in a stable result and improves nasal symmetry and the angulation of the cleft side teeth.  相似文献   
990.
Cholera toxin B (CTB) is often envisaged and used as an immune stimulating agent in protocols for mucosal immunization. However, the nature of the CTB used (natural vs recombinant) is frequently not taken in consideration. This is important since the usage of natural CTB in mucosal immunization regimen and the mucosal response resulting from such an immunization can be effected by the presence of the CTA subunit in commercial CTB preparations. To clarify this, we have compared natural vs recombinant CTB in an intranasal (i.n.) mucosal immunization procedure using ovalbumin (OVA) as antigen. The results show that recombinant CTB induces similar immune responses like natural CTB. Furthermore, our experiments show that covalent coupling of OVA to CTB is not required for the induction of OVA specific mucosal and systemic immune responses upon i.n. immunization.  相似文献   
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