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61.
ABSTRACT: Effects of formulation (lipid presence, type of starch, and plasticizer) on microstructure, water vapor (WVP) and gas (GP) permeabilities of films and coatings were analyzed. Plasticizer was necessary to maintain film and coating integrity and to avoid pores and cracks. Films made from high amylose starch showed lower WVP and GP than regular corn starch films; permeabilities of films with sorbitol (20 g/L) were lower than those with glycerol. The addition of 2g/L sunflower oil to the formulations decreased WVP of starch-based films; X-ray diffraction and Differential Scanning Calorimetry experiments demonstrated that films with plasticizer and lipid showed lower crystalline-amorphous ratio compared to films without additives. Microstructural observations helped explain the decrease of the film permeabilities during storage.  相似文献   
62.
The goal of this study was to measure shifts in alcohol expectancies from childhood into adolescence while controlling for changes in the psychometric properties of the instrument. One thousand nine hundred ninety-three 4th-grade and 1,632 9th-grade students from South Dakota rated the likelihood that 23 outcomes would result from alcohol use. These expectancies were modeled using a 2-factor confirmatory factor analysis. After differences in the psychometric properties of the instrument were controlled, the cohorts were distinguished by a large difference in Alcohol Positivity, with older participants viewing alcohol's effects more positively. Additionally, older participants displayed greater Alcohol Potency, believing that alcohol has a larger impact on all outcomes. There were also significant differences in the interpretation of the alcohol expectancies items across cohorts. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
63.
From 1969 to 1990 there were 309 patients with differentiated thyroid carcinoma (241 papillary and 68 follicular) treated with radioactive iodine for functioning node metastases alone (n = 191) or distant metastases (n = 118) with or without node metastases. These patients represented 32.7% of 945 patients treated in our institution during the same period. Initial treatment included near-total thyroidectomy and 131I ablation of postsurgical thyroid residue, followed by L-thyroxine suppressive therapy. At the end of follow-up (mean 5.8 years), 146 patients (76.4%) in the group with nodal metastases were considered cured, as assessed by clinical and laboratory evaluation including whole body scan (WBS) and serum thyroglobulin (Tg) levels; 32 patients (16.7%) had persistent disease. Loss of 131I uptake in persistent metastatic lesions occurred in five patients (2.6%), and newly developed distant metastases occurred in eight patients (4.2%). Of the patients with distant metastases, 36.4% were cured by 131I. Distant metastases from papillary carcinomas had a higher cure rate than follicular carcinomas (p < 0.01). The metastases of four patients (5.2%) lost the property to take up radioiodine. Lung and bone metastases detectable by WBS but not by radiography were most likely to be cured by 131I. The overall survival at the end of follow-up was 95.8% in patients with only lymph node metastases and 76.0% in those with distant metastases. Tumor-related deaths were 3.6% and 23.7%, respectively. Our data indicate that 131I therapy is highly effective in the treatment of lymph node metastases from differentiated thyroid carcinoma.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
64.
Expression of intercellular adhesion molecule-1 (ICAM-1) and endothelial-leukocyte adhesion molecule-1 (ELAM-1) on endothelium can be considered a critical early step for leukocyte migration from blood to tissues during inflammatory processes. Increased circulating soluble ICAM-1 (sICAM-1) levels have been found in sera from patients with Graves' disease (GD) with or without ophthalmopathy. Serum soluble ELAM-1 (sELAM-1) levels have not been measured in these patients. The aim of this study was to clarify the behavior of sICAM-1 and sELAM-1 levels in patients with hyperthyroidism due to GD with or with or without ophthalmopathy and in hyperthyroid patients with toxic thyroid adenoma. We studied sICAM-1 and sELAM-1 levels in 130 subjects (age 23-54 yr), grouped as follows: group 1, 30 untreated hyperthyroid GD patients (21 females and 9 males) with active ophthalmopathy; group 2, 26 euthyroid GD patients (16 females and 10 males) with active ophthalmopathy; group 3, 33 hyperthyroid GD patients (22 females and 11 males) without ophthalmopathy; group 4, 11 untreated hyperthyroid patients (7 females and 4 males) with single toxic adenoma; and a control group of 30 healthy subjects (21 females and 9 males). sICAM-1 and sELAM-1 concentrations were measured by a sandwich enzyme linked immunosorbent assay (ELISA) method. Groups 1, 2, and 3 (P < 0.001 for all 3 groups) but not group 4 showed increased sICAM-1 levels compared with the control group. However, groups 1 and 2 (P < 0.001 for both) showed higher values of sICAM-1 than group 3, and group 1 showed higher sICAM-1 levels than group 2 (P < 0.002). Groups 1 and 2 (P < 0.001 for both) but not groups 3 and 4 showed sELAM-1 levels significantly higher than the control group and positively correlated to the severity score of Graves' ophthalmopathy (GO) (P < 0.002 for group 1 and < 0.01 for group 2). Our results confirm that increased sICAM levels in GD patients with or without ophthalmopathy (with higher levels in patients with GO) but not in hyperthyroid nonautoimmune patients may be the consequence of orbital and thyroid inflammation, and they also suggest that sICAM concentrations could reflect the degree of inflammatory activity. Increased sELAM-1 concentrations only, in patients with ophthalmopathy with or without hyperthyroidism significantly correlated to severity score of GO, suggest the measurement of sELAM-1 levels as a specific marker of endothelium activation in GO.  相似文献   
65.
With a national household probability sample of 4,023 telephone-interviewed adolescents ages 12-17, this study provides prevalence, comorbidity, and risk-factor data for posttraumatic stress disorder (PTSD), major depressive episode (MDE), and substance abuse/dependence (SA/D). Roughly 16% of boys and 19% of girls met criteria for at least 1 diagnosis. Six-month PTSD prevalence was 3.7% for boys and 6.3% for girls, 6-month MDE prevalence was 7.4% for boys and 13.9% for girls. and 12-month SAM prevalence was 8.2% for boys and 6.2% for girls. PTSD was more likely to be comorbid than were MDE and SA/D. Results generally support the hypothesis that exposure to interpersonal violence (i.e., physical assault, sexual assault, or witnessed violence) increases the risk of these disorders and of diagnostic comorbidity. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
66.
A new continuous-flow recycle microwave reactor suitable for organic synthesis has been developed to handle 0.51 quantities of reagents. The apparatus, which is designed for laboratory use, operates at atmospheric pressure in open- or closed-loop mode. It is fitted with a temperature control system. We describe this novel reactor and illustrate its efficiency with examples of organic syntheses carried out using both homogeneous and heterogeneous reactions.  相似文献   
67.
Between 1983 and 1994 the incidence of secondary haematological neoplasms (SHM) was evaluated in 1170 new cases of ALL enrolled in the GIMEMA trials. Of the 942 patients who achieved complete remission (CR); seven developed a SHM: four AMLs and three NHLs. The median latency from onset of ALL and of secondary haematological neoplasm was 69 months for AML and 61 months for NHL. Three out of four patients with secondary AML were unresponsive to the new chemotherapy and died, whereas the fourth patient achieved a new CR. Among the three NHL cases, two patients are presently alive in CR, whereas the third patient was refractory to chemotherapy and died. The relative risk of haematological malignancy among the GIMEMA trials population, as compared to that of the Italian Cancer Registries, was 15.25-fold higher, and the actuarial estimated cumulative proportion of ALL patients with a secondary haematological neoplasm at 5 and 10 years were 0.59% and 3.63% respectively. The incidence of adult ALL who developed a SHM, although apparently lower than in the paediatric ALL series, was higher when compared to the normal population. The difference between paediatric and adult ALL is probably due to the lack of craniospinal radiotherapy and to the lower doses of epipodoxiphyllotoxins used in adult trials. The higher percentage of childhood ALL with a prolonged event-free survival could result in an increase of secondary neoplasms in these cases, which suggests that secondary haematological neoplasms in adult ALL patients are real, although rare, events.  相似文献   
68.
We assessed human myelin basic protein (MBP) binding IgM levels in CSF. MBP is the most studied putative antigen in multiple sclerosis (MS) and immune responses against it may be involved in the demyelination process. We also correlated these levels with EDSS score and other parameters of disease progression and prognosis, both at the time of CSF analysis and during follow-up. CSF IgM anti-MBP levels were assayed by measuring total IgM levels with solid-phase ELISA in CSF samples from 66 patients with relapsing-remitting MS, 11 subjects without neurological diseases, 20 patients with non-inflammatory neurological diseases and 7 patients with lymphocytic meningitis, before and after immunoabsorption with human MBP. Confirmation of IgM binding specificity was performed by immunoblotting of positive CSF samples onto MBP coated-nitrocellulose sheets. Clinical evaluation (disability score, number and time of attacks) was performed during a mean follow-up of 2.7 +/- 1.1 years. 23 of the 66 relapsing-remitting MS patients (33.8%) had elevated IgM anti-MBP levels. In this patient subgroup, IgM anti-MBP levels correlated with the IgM index (r = 0.71; P = 0.0001), but not with CSF/serum albumin (r = 0.08; P = 0.72). In the first year of follow-up, patients with low IgM anti-MBP suffered from more numerous attacks than those with elevated levels (0.86 +/- 0.63 versus 0.43 +/- 0.58; P = 0.017). Patients with high IgM binding to MBP had a first attack during follow-up in a significantly higher time than those with low binding (28.87 +/- 4.7 versus 17 +/- 2.6 months, respectively; P = 0.005) and reached a decrease of 0.5 EDSS point significantly faster than those with low IgM (16.17 +/- 1.2 versus 29.7 +/- 2.6 months, respectively; P = 0.0002). A similar significant finding was observed when the time to reach low disability score (EDSS < or = 2.0) was analyzed (10.7 +/- 2.57 +/- 3.3 months, respectively; P = 0.014). These findings demonstrate that in a subgroup of MS patients, elevated CSF levels of IgM anti-MBP are associated with early favorable course and therefore suggest that IgM binding to MBP could be a possible prognostic marker in relapsing-remitting MS to select early MS patients for future trials.  相似文献   
69.
70.
OBJECTIVE: The measurements of transient evoked otoacoustic emissions and distortion-product otoacoustic emissions are being used increasingly, both as an objective hearing test clinically, and as a research tool to investigate the micromechanical aspects of cochlear function. We hypothesized that localized damage in the apical or middle cochlear turns may have an influence on the micromechanics and the function of adjacent, apparently normal cochlea. For that purpose, we used an animal model of localized apical and middle-turn cochlear lesions. METHOD: Extent of damage was assessed by scanning electron microscopy and the function of the damaged cochlea by change in the otoacoustic emission (OAE) levels. RESULTS: We found that localized damage to the apical or middle turn may be accompanied by an increase in OAE measured from adjacent apparently normal cochlea. CONCLUSION: Explanations to this phenomenon are suggested, and possible clinical associations such as to Meniere's disease and to sudden hearing loss are reviewed.  相似文献   
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