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991.
A national telephone survey was conducted of 1,620 randomly selected U.S. residents who spoke English, were at least 18 years old, and resided in households with kitchen facilities. Respondents were interviewed about their recognition of foodborne pathogens, foods at risk for transmitting infection, knowledge of safe food handling, and food-handling practices. One-third of the respondents who prepared meals reported unsafe food hygiene practices: e.g., they did not wash hands or take precautions to prevent cross-contamination from raw meat. Unsafe practices were reported more often by men, adults 18 to 29 years of age, and occasional food preparers than by women, persons 30 years old or older, and frequent food preparers. Respondents who identified a food vehicle for Salmonella spp. were more likely to report washing their hands and cleaning cutting boards after preparing raw meat and poultry. The results raise concerns about consumer food-handling practices. The influence of food safety training, food-handling experience, and age on food-handling practices should be studied further. Awareness of a food vehicle for Salmonella spp., for example, may indicate knowledge of the etiology of foodborne disease that promotes safe food handling. Understanding the factors associated with safe food handling will assist in development of effective safe-food instruction programs.  相似文献   
992.
We examined the hypoxic tolerance phenomenon in vitro. Brief exposure to hypoxia induced the production of basic fibroblast growth factor (bFGF) mRNA and protein in rat cortical neurons and protected them from hypoxic injury. Cortical neurons were cultured from 18th-day rat embryos in a serum-free medium and subjected to brief (4 h) and/or prolonged (24 h) hypoxia. Neuronal damage was assessed by quantifying lactate dehydrogenase (LDH) activity in the medium. After brief hypoxia, LDH release was identical to that of the controls, whereas prolonged hypoxia caused a significant increase in LDH release, indicating neuronal death. However, if brief hypoxia was applied 2 days prior to the prolonged hypoxia, no increase in LDH release was observed. The bFGF mRNA expression was assessed with Northern blot and protein immunoreactivity with Western blot analysis. The brief period of hypoxia caused a 2.5-fold increase in bFGF mRNA and considerable bFGF protein expression 1 day later, but prolonged hypoxia caused increase in the expression of bFGF mRNA at 2 days and no protein expression until 3 days after the start of the hypoxia. When cells were subjected to prolonged hypoxia 2 days after brief hypoxia, however, no increase in bFGF mRNA was observed, while bFGF protein was expressed continuously. We also observed that exogenously applied bFGF reduced neuronal injury produced by prolonged hypoxia. The results obtained with this model suggest that brief hypoxia induces bFGF protein and thus tolerance to subsequent lethal hypoxia. Basic FGF might play a role as a tolerance-associated factor in this process. Thus, an in vitro model is useful for assessing the response of cortical neurons to hypoxic stress and for researching new factors related to ischemic tolerance.  相似文献   
993.
Standard Gibbs free energy of formation (ΔGf0), an important property needed in design calculations has been estimated using molar refraction, RM. The linear relationships derived between ΔGf0 and RM tested with the data on 8 series of hydrocarbons at 228 compounds yielded average deviations comparable to the methods cited in recent literature. The method can be used as an alternative to the existing ones, because of its simplicity combined with reasonable accuracy.  相似文献   
994.
We evaluated the effect of repeated administration of OC125 F(ab')2 fragments on cancer antigen (CA) 125 determination in 210 serum samples from 30 patients. We found falsely high CA 125 concentrations in 142 (68%) samples, using a homologous CA 125 enzyme immunoassay (EIA) with OC125 antibodies. The Truquant OV2 method, which involves two other murine antibodies, and the IMx CA 125 method, which uses sheep antibodies as capture antibodies, resulted in only slightly increased (false-positive) values in some samples with exceptionally high CA 125 EIA values. We measured falsely low CA 125 values in 37 (18%) samples with the Truquant OV2 method. Interferences could be eliminated by removal of serum IgG. Our results suggest that interferences are to some extent caused by anti-idiotypic IgG induced by OC125 administration. Assays involving nonmurine anti-CA 125 antibodies as capture antibodies seem to be most suited for CA 125 determination after OC125 treatment, but in every case an apparent increase of CA 125 after OC125 infusion should be validated.  相似文献   
995.
PURPOSE: To determine the value of gadolinium in routine head MR imaging of HIV-infected patients. METHODS: One hundred and three consecutive human immunodeficiency virus-infected patients referred for head MR imaging were scanned without and with intravenous gadopentetate dimeglumine (Gd-DTPA) contrast. RESULTS: The precontrast scans of 82 patients were either normal, or had atrophy or diffuse white matter changes only. Sixteen of these 82 demonstrated enhancing abnormalities: eight meningeal/ependymal enhancement and eight focal enhancing lesions. Twenty-one of the 103 scans had focal or mass lesions on the precontrast images; in eight of these scans, new information was obtained with Gd-DTPA. Of the 24 patients in both groups where new information was obtained with Gd-DTPA, the information contributed to a change in the clinical care of nine patients. CONCLUSION: Gadolinium-enhanced MR is useful in the management of selected patients with human immunodeficiency virus infection, for example those with symptoms suggesting meningeal involvement, focal brain lesions, or if the unenhanced MR does not explain all the patient's symptoms.  相似文献   
996.
The effects of celebrity self-disclosure of HIV seropositivity on perceptions of HIV and AIDS were investigated. AIDS-related interest and knowledge measures were collected from 468 men before and after basketball star Earvin "Magic" Johnson's self-disclosure of HIV seropositivity. Increased interest in AIDS paralleled media coverage of the announcement, with the most substantial effects occurring within 2 wks. Perceived impact of the disclosure was greatest among African-American men and men who had not previously known someone with HIV/AIDS. Celebrity self-disclosure appears to affect perceptions through mechanisms similar to those involved in personally knowing someone infected with HIV. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
997.
The human obesity gene map: the 1997 update   总被引:1,自引:0,他引:1  
An update of the human obesity gene map incorporating published results up to October 1997 is presented. Evidence from Mendelian disorders exhibiting obesity as a clinical feature; single-gene mutation rodent models; quantitative trait loci uncovered in human genome-wide scans and in crossbreeding experiments with mouse, rat, and pig models; association and case-control studies with candidate genes; and linkage studies with genes and other markers is reviewed. All chromosomal locations of the animal loci are converted into human genome locations based on syntenic relationships between the genomes. A complete listing of all of these loci reveals that all but chromosome Y of the 24 human chromosomes are represented. Some chromosomes show at least three putative loci related to obesity on both arms (1, 2, 6, 8, 11, and 20) and several on one chromosome arm only (3p, 4q, 5q, 7q, 12q, 13q, 15q, 15p, 22q, and Xq). Studies reporting negative association and linkage results are also listed, with the exception of the unlinked markers from genome-wide scans.  相似文献   
998.
We studied 100 healthy children looking for lactose malabsortion. We performed in all of them the lactose breath test. We found a 10% with lactose malabsortion. There was no correlation between lactose breath test and fecal reducing substances.  相似文献   
999.
The authors report the case of a 32 year old woman who was shot with a shotgun. Acute inferior wall infarction was detected fortuitously on electrocardiography and coronary angiography showed occlusion of the right coronary artery with lead shot. The single coronary lesion, absence, of other cardiac complications (haemopericardium, cardiac perforation, ...) and the favourable outcome with conservative medical treatment has not been previously reported to the authors' knowledge.  相似文献   
1000.
Patients with carcinoma of the stomach who underwent curative resection were randomized to total gastrectomy (n = 49), total gastrectomy and an S-shaped gastric substitute (n = 28) or subtotal gastrectomy (n = 12); all had a Roux-en-Y reconstruction. The gastric substitute and gastric remnant allowed a volume of 400-500 ml to be installed without increments in basal pressures. The corresponding volume in the Roux limb was 100 ml. Energy intake was approximately 120 kJ/kg preoperative weight per day 3 months after operation, and then remained constant. Patients who had subtotal gastrectomy ate less (91.7 kJ/kg preoperative weight) 3 months after operation, but thereafter increased their intake. Patients allocated to have a gastric pouch or subtotal gastrectomy complained more frequently of adverse postprandial symptoms (P < 0.03) as a major cause of reduced calorie intake. The construction of a gastric reservoir did not improve nutritional adaptation after surgery for gastric carcinoma.  相似文献   
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