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161.
The sneeze reflex is a valuable tool for exploring the maturation of the respiratory control in the newborn as it alters both inspiratory and expiratory activities. Air puff stimulation of the superior nasal meatus innervated by ethmoidal afferents consistently evokes sneeze in adult cats. Such stimulation evokes only a reinforcement of expiratory activities in newborn kittens. This study demonstrates that the pattern of Fos-like immunoreactivity evoked by nasal stimulation changes during functional maturation of sneeze. Nasal stimulation evoked immunoreactivity (i) in the trigeminal sensory complex, at the levels where nasal afferents project, (ii) in the reticular formation, (iii) in the solitary complex and (iv) in the parabrachial area of mature kittens. The evoked immunoreactivity was the same in newborn kittens as in mature kittens in the projection areas of the nasal primary afferents. Fos response was less than half that in mature kittens in the reticular formation and absent in the solitary complex or the parabrachial area. Sneeze can be elicited from the time when evoked immunoreactivity in the solitary complex and the parabrachial area is above control levels. These data provide evidence that the maturation of sneeze is dependent on the development of central relays allowing peripheral inputs to be integrated by neurons engaged in respiratory control. 相似文献
162.
Fabrice Perin Laurence Routledge Oumar N'Doye Mamadou M'Bodj Gérard Normier Alain Le Pape 《Nuclear medicine and biology》1996,23(8):947-955
The potential of 99m-Tc-J001 for the investigation of inflammatory lesions via the targeting of recruited macrophages (Mφ) has already been documented in several experimental models and in human diseases. To achieve a functional imaging of inflammation via Mφ targeting, minimal labeled colloid content and high in vivo stability of 99mTc-J001 are essential. The actual specificity of such scintigraphy is closely dependent upon the radiolabeling of only the J001 molecules available for Mφ targeting. To develop an appropriate radiopharmaceutical kit, optimization of the labeling conditions was achieved from a series of pilot formulations that were evaluated for radiolabeling efficiency and both in vitro and in vivo 99mTc-J001 stability. Colloids were characterized using autocorrelation spectroscopy and multiangle laser-light scattering, radioactive colloid content of the formulations being deduced from biodistribution studies. This work has made possible the definition of a formulation exhibiting a radiolabeling yield >97.0%, associated with in vivo stability and minimal colloid formation, thus greatly enhancing the specificity of such macrophage scintigraphy. 相似文献
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166.
Grova N Monteau F Le Bizec B Feidt C Andre F Rychen G 《Journal of analytical toxicology》2005,29(3):175-181
A fast and efficient multiresidue extraction-purification procedure was developed for low levels (ppb range) of phenanthrene and hydroxyphenanthrene in biological matrices, in order to quantify phenanthrene and metabolites in blood, milk, urine, and biological tissues of lactating goats. Detection and identification of the analytes (phenanthrene and 1-, 2-, 3-, 4-, and 9-hydroxyphenanthrene) were achieved using gas chromatography coupled to mass spectrometry. Deuterium-labeled phenanthrene was used as internal standard for phenanthrene and 2-OHfluorene for metabolites. The developed method includes enzymatic hydrolysis, liquid-liquid extraction, and Envi-Chrom P SPE column purification. Analyses were performed in the selected ion monitoring mode to achieve ad hoc sensitivity in accordance with analyte concentrations in food samples. Detection limits were between 2.3 and 5.1 ng/mL (ppb) for milk samples, 0.5 and 2.5 ng/mL for urine and blood samples, and 1.9 and 8.0 ng/g for tissue samples. This original multiresidue and multimatrix analytical methodology was applied to metabolism studies and polycyclic aromatic hydrocarbon (PAH) risk assessment. We demonstrated, for the first time, that metabolites were present in milk. These results suggested that usual PAHs analysis methods based on the detection of native molecule are not representative of the real contamination of biological matrices. 相似文献
167.
Jenny JY Boeri C El Amrani H Dosch JC Dupuis M Moussaoui A Mairot F 《The Journal of trauma》2005,58(6):1179-1182
BACKGROUND: We tested the hypothesis that it was possible to decrease the number of performed x-rays after a knee trauma without delayed fracture diagnosis by using the Ottawa knee rules. METHODS: Patients had routine x-rays of the injured knee during the first stage of the study and selective x-rays during the second stage. All patients were followed up to 6 months after the trauma. RESULTS: 138 patients were included in the first stage; 57 had negative Ottawa criteria: no fracture was observed; following the Ottawa rules, 41% of the x-rays could have been avoided. 178 patients were included in the second stage; 63 patients had negative Ottawa criteria: no fracture was diagnosed during the whole follow-up; 35% of the x-rays have been avoided. CONCLUSIONS: Ottawa rules allowed decreasing the number of x-rays performed after a knee trauma by 35% with a sensitivity for a knee fracture detection of 100%. 相似文献
168.
Duffau P Morel D Basseau F Merville P Berger F Potaux L 《Néphrologie & thérapeutique》2005,1(2):131-134
An Antopol-Goldman lesion or subepithelial pelvic hematoma of the kidney is a rare cause of hematuria. We described a 26 year-old man hospitalized for macroscopic hematuria associated with a subepithelial hematoma whose development might have been favored by arterial hypertension secondary to a renal artery stenosis. 相似文献
169.
Duval B Gîlca V Boulianne N De Wals P Massé R Trudeau G De Serres G 《The Pediatric infectious disease journal》2005,24(3):213-218
BACKGROUND: Few data are available concerning the long term immunogenicity of the pediatric doses of hepatitis B vaccines given to preteenagers. The long term effect of the booster dose in teenagers is unknown. We evaluated the immunogenicity of 2 pediatric hepatitis vaccines after primary vaccination and after a booster dose. METHODS: A prospective 15-year follow-up study of the immunogenicity of 2 hepatitis B vaccines was initiated in 1995 in Quebec City, Canada. One year apart, 1129 children 8-10 years old received Engerix-B 10 microg (EB), and 1126 received Recombivax-HB 2.5 microg (RB) vaccine after a 0-, 1-, 6-month schedule. After 5 years, one-third of the 2 cohorts were randomly selected. A booster dose of EB 10 microg or RB 5 microg was administered according to the vaccine used in the primary immunization. Antibodies were measured before, 1 month after and 1 year after the booster injection. RESULTS: Before the booster dose, anti-HB surface antibody (HBs) was detected in 94.7% of the EB subjects and in 95.2% of the RB subjects (P = 0.85). The geometric mean titer (GMT) was higher in the EB than in the RB group (252 mIU/mL versus 66 mIU/mL, P < 0.0001). One month after the booster, 99.7% of subjects in the EB group and 99.6% in the RB group had a detectable anti-HBs, and 99.0 and 99.3%, respectively, had anti-HBs > or =10 mIU/mL. The anti-HBs GMT was 113,201 mIU/mL in the EB and 16,623 mIU/mL in the RB groups (P < 0.0001). One year after the booster, 99.3% of subjects in the EB group and 100% in the RB group had detectable anti-HBs, and 97.9 and 98.5% respectively, had anti-HBs > or =10 mIU/mL. The anti-HBs GMT was 14,028 mIU/mL in the EB and 3437 mIU/mL in the RB group (P < 0.0001). CONCLUSIONS: The immunity persists for at least 5 years after the primary vaccination with both pediatric vaccines in 99% of children vaccinated at the age of 8-10 years. It confirms that no booster is needed at that point. 相似文献
170.
Duval B De Serres G Ochnio J Scheifele D Gîlca V 《The Pediatric infectious disease journal》2005,24(6):514-519
BACKGROUND: Hepatitis A vaccines provide consistent, long-lasting protection and have been available for almost 10 years in Canada, but their use remains limited. It is difficult to assess their optimal utilization given that our knowledge of hepatitis A epidemiology in Canada is fragmentary. Unlike the United States, no nationwide study of hepatitis A prevalence has ever been done in Canada. Consequently we do not know the incidence of infection in children and what would be the most appropriate age for hepatitis A vaccination. OBJECTIVE: To estimate the proportion of 8- to 13-year-old children who have been infected with hepatitis A virus (HAV) and the risk factors for this infection on a nationwide scale. METHODS: Children were sampled in 10 Canadian provinces, comprising 5 regions, using random digit dialing methodology with regional stratification. Demographic data and information about risk factors for hepatitis A were collected by the telephone interviewers. Oral fluid samples were self-collected and mailed to the laboratory, where they were tested for anti-HAV IgG. RESULTS: Of 6740 contacted families with a child of required age, 1688 (25%) agreed to participate and answered the questionnaire. From these, 1074 oral fluid samples were received, and 1057 could be analyzed. Anti-HAV IgG was detected in 2.7% of subjects, with variation by region from 0.8 to 3.4%. The parents of 54 subjects (5.1%) reported that their child had previously been vaccinated against HAV. Anti-HAV IgG was present in 2.0% of unvaccinated subjects, among whom antibody prevalence was 19.4% in children born in HAV-endemic countries, 6.1% in Native children and 4.2% in travelers to endemic countries. In multivariate analysis of all subjects, the presence of anti-HAV IgG was significantly associated with birth in an endemic country, travel to an endemic country, Native status (American Indian and Inuit population), female gender and vaccination against HAV. In nonvaccinated, non-Native children born in Canada who did not travel to endemic countries, anti-HAV prevalence was 1.1%. CONCLUSIONS: The risk for hepatitis A during childhood is low in Canada. Almost all teenagers (>97%) would be at risk for infection in case of contact with HAV. Changes in immunization policy against hepatitis A should be considered. 相似文献