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For effective treatment of young adult psychiatric patients, recognition of the complex interaction of developmental processes and psychopathology is necessary. An inpatient young adult service is described that uses academic engagement to mitigate the threat of hospitalization to identity, maintain age-appropriate activities, and facilitate the transition from hospital to educational settings. Application of the program to other milieus is discussed. 相似文献
34.
Daniel Buser Britt Hoffmann Jeanpierre Bernard Adrian Lussi Daniel Mettler Robert K. Schenk 《Clinical oral implants research》1998,9(3):137-150
In recent years, bone grafts and bone substitutes have been increasingly utilized underneath barrier membranes to optimize the treatment outcome of bone reconstructive therapy for defects in the alveolar process. In the present study, 4 different filling materials were evaluated in bone defects of similar dimensions in the mandible of miniature pigs. Blood clots and autografts were used as controls. The defects were covered with barrier membranes and allowed to heal for 4, 12 or 24 weeks. Histologic examination demonstrated that bone repair progressed through a programmed sequence of maturation steps closely resembling the pattern of bone development and growth regardless of whether bone grafts or substitutes were present or not. Histomorphometric analysis showed that autologous bone grafts (autografts) had the best osteoconductive properties during the initial healing period, with 39% of newly formed bone inside the membrane-covered defects at 4 weeks of healing. In addition, 87% of the graft surfaces were already covered by bone at this time. Both values were significantly higher for autografts than for the 4 alternative bone fillers (P < or = 0.05). At 12 weeks, these differences were no longer apparent, with all 5 filling materials showing similar values. Among the tested bone substitutes, tricalcium phosphate (TCP) showed a significantly higher percentage of bone fill at 24 weeks of healing. It can be concluded that sites filled with autografts clearly demonstrated the best results underneath barrier membranes in the early phase of healing. As far as degradation and substitution are concerned, TCP showed the most promising results. This filler, however, needs to be tested further in a more demanding animal model. Less favorable results were obtained for coral-derived hydroxyapatite granules and for demineralized freeze-dried bone allografts. 相似文献
35.
Supercritical fluid extraction in the determination of tobacco-specific N-nitrosamines in smokeless tobacco. 总被引:6,自引:0,他引:6
B Prokopczyk D Hoffmann J E Cox M V Djordjevic K D Brunnemann 《Chemical research in toxicology》1992,5(3):336-340
A new approach to the analysis of the carcinogenic, tobacco-specific N-nitrosamines (TSNA) in moist snuff tobacco is based on the extraction of tobacco with methanol-modified supercritical carbon dioxide. Extracted TSNA are trapped across a glass cartridge filled with Tenax GR, from which they are subsequently released by thermal desorption and analyzed by capillary gas chromatography with a thermal energy analyzer. The analytical recoveries for the major TSNA range from 83 to 98%; the detection limits are below 2 ng/g. The methodology is fast, reproducible, highly selective, and sensitive. The supercritical fluid extraction (SFE) releases up to 7 times more of the highly carcinogenic 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone (NNK) from tobacco than has been determined after conventional solvent extraction. Studies have confirmed that this is not an artifact. In contrast, the cyclic N-nitrosamines, N'-nitrosonornicotine, N'-nitrosoanabasine, and N'-nitrosoanatabine, showed no significant quantitative differences whether determined by the SFE method or the conventional solvent extraction method. 相似文献
36.
P L Tisdale B D Collier H M Kauffman M B Adams A T Isitman R S Hellman R G Hoffmann S A Rao T Joestgen L Krohn 《Journal of nuclear medicine》1986,27(8):1266-1272
A prospective evaluation of 111In-labeled platelet scintigraphy (IPS) for the early diagnosis of acute postoperative renal transplant rejection (TR) was undertaken. The results of IPS were compared with in vitro biochemical tests, the clinical finding of graft tenderness, and combined [99mTc]DTPA and [131I]orthoiodohippurate scintigraphy. With a sensitivity of 0.93 and a specificity of 0.95, IPS provided otherwise unavailable diagnostic information. Furthermore, postoperative IPS was a good predictor of long-term allograft survival. 相似文献
37.
Simone Maschauer Olaf Prante Markus Hoffmann J Thiess Deichen Torsten Kuwert 《Journal of nuclear medicine》2004,45(3):455-460
The contribution of (18)F-FDG uptake by endothelial cells to uptake values measured by PET in various tissues is as yet unclear. We therefore sought to characterize (18)F-FDG uptake in an in vitro model of human endothelial cells. METHODS: Commercially obtained human umbilical vein endothelial cells (HUVECs) were seeded in 6-multiwell plates 48-96 h before incubation with 1-2 MBq (18)F-FDG per well. Radioactivity measurements were performed after washing and mechanical dissolvation of the cellular monolayers. Cellular (18)F-FDG uptake was referred to protein concentration. This experimental protocol was subsequently varied to study the effect of different parameters of interest. Furthermore, radio-thin-layer chromatography was used to identify intracellular (18)F-FDG metabolites. (18)F-FDG uptake in HUVECs was compared with that by a human monocyte-macrophage (HMM) preparation and by glioblastoma cells (GLIOs) under identical experimental conditions. RESULTS: (18)F-FDG accumulated in HUVECs in a time-dependent manner and was trapped mainly as (18)F-FDG-6-phosphate and (18)F-FDG-1,6-diphosphate. Unlabeled glucose and cytochalasin B competitively inhibited (18)F-FDG uptake, whereas phlorizin had no significant effect. Glucose deprivation significantly enhanced (18)F-FDG uptake by a factor of 2.7, whereas sodium depletion had no significant influence. HUVECs treated with vascular endothelial growth factor (VEGF) showed a significant 82% increase in (18)F-FDG accumulation after a 2-h exposure to 50 ng/mL VEGF. (18)F-FDG uptake in HUVECs was significantly higher than that in HMMs and in the range of the uptake values measured in GLIOs. CONCLUSION: (18)F-FDG accumulates in HUVECs by mechanisms analogous to those in neoplastic cells or neurons. VEGF significantly stimulates endothelial (18)F-FDG uptake. The observed differences in (18)F-FDG uptake between HUVECs, HMMs, and GLIOs are difficult to extrapolate to in vivo conditions but stimulate further studies on the contribution of endothelial (18)F-FDG uptake to the overall uptake of that tracer in neoplastic or vascular lesions. 相似文献
38.
Hormonal regulation in insects: facts, gaps, and future directions 总被引:15,自引:0,他引:15
39.
Wolfram Grimm Jens Winzenburg Ursula Knop Jürgen Hoffmann Volker Menz Frank Grote Bernhard Maisch 《Annals of noninvasive electrocardiology》1997,2(1):20-26
Objective: This prospective study was designed to compare incidence and clinical significance of ventricular late potentials between patients with idiopathic dilated cardiomyopathy (IDC) and postinfarct patients (CAD) using exactly the same method of signal-averaged electrocardiography (SAECG) in both patient groups. Methods: Time-domain analysis of SAECG was performed in 120 consecutive patients with IDC, 120 patients with CAD, and 60 healthy controls. Ventricular late potentials were detected in 27 of 120 patients with IDC (23%) compared to 41 of 120 patients with CAD (34%; P < 0.05). Results: Ventricular late potentials were found in 2 of 60 controls (3%). During 15 ± 7 months follow-up, serious arrhythmic events occurred in 17 of 120 patients with IDC (14%) and in 13 of 120 patients with CAD (11%). The sensitivity of ventricular late potentials for future arrhythmic events was 35% for IDC compared to 77% for CAD (P < 0.05). The positive predictive value of late potentials detected by time-domain analysis was 22% for IDC versus 24% for CAD (P = ns). Conclusion: In this selected patient population with IDC and CAD, time-domain analysis of SAECG revealed a lower incidence of ventricular ate potentials in patients with IDC as compared to postinfarct patients. Whereas ventricular late potentials had a high sensitivity but a low positive predictive value for identification of postinfarct patients with serious arrhythmic events during follow-up, both sensitivity and positive predictive value of ventricular late potentials for future serious arrhythmic events were low in the setting of IDC. 相似文献
40.
T. Eger L. Zller H.-P. Müller S. Hoffmann D. Lobinsky 《European journal of oral sciences》1996,104(2):112-117
Actinobacillus actinomycetemcomitans has been implicated in the pathogenesis of several forms of early onset and refractory adult periodontitis. Early diagnosis of colonization of the oral cavity might be of importance in order to initiate preventive measures. The aim of the present study was to determine the potential diagnostic value of oral mucosal and salivary tests to identify, among healthy young men with no or minor periodontal disease, individuals colonized by A. actinomycetemcomitans. Two hundred and one male recruits. 18–25 yr of age, took part in the present study. Mean values of periodontal parameters suggested only minor periodontal disease. Of the sites, 64.8±17.6% (mean ± SD) had a periodonta) probing depth (PPD) of 1 or 2 mm. only 1.6±2.9% deep sites of 5 mm were detected. More than 1000 subgingival and extracrevicular samples were selectively cultivated for A. actinomycetemcomitans. The organism was isolated in 55 subjects (21%). The odds for presence of at least 1 deep site of 5 mm was increased by a factor 1.99 if A. actinomycetemcomitans could be recovered. In identifying subjects colonized by A. actinomycetemcomitans. diagnostic test parameters sensitivity and predictive value for a negative test were 74.5±5.9% and 91.1±2.3%', respectively, for both saliva and dorsum of tongue samples. In contrast, pooled subgingival plaque from mesial surfaces of 1st molars was only 34.5±6.4% sensitive: the negative predictive value was 80.2±3.0%. The results point to a high diagnostic value of oral mucosal and especially saliva samples to identify young adult individuals colonized by A. actinomycetemcomitans. 相似文献