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A blinded cohort study was conducted in 2000 to better understand the emergence of La Crosse virus infection in eastern Tennessee, with special emphasis on the potential mosquito vector(s). Children with suspected central nervous system infection were enrolled at the time of clinical presentation at a large pediatric referral hospital. Clinical, environmental, and entomological data were collected prior to case confirmation. Sixteen of the 40 children included in the final analysis were confirmed to have La Crosse infection by a fourfold increase in antibody titers between collection of acute- and convalescent-phase sera. Factors significantly associated with La Crosse infection included average number of hours per day spent outdoors (5.9 for La Crosse virus cases vs. 4.0 for noncases, p = 0.049); living in a residence with one or more tree holes within 100 m (relative risk = 3.96 vs. no tree holes within 100 m, p = 0.028); and total burden of Aedes albopictus (number of female and male larvae and adults collected at a site), which was more than three times greater around the residences of La Crosse virus cases versus noncases (p = 0.013). Evidence is accumulating that the newly introduced mosquito species Ae. albopictus may be involved in the emergence of La Crosse virus infection in eastern Tennessee.  相似文献   
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Abnormalities in monoamine neurotransmission have been implicated in the pathogenesis of alcoholism, mood disorders and schizophrenia. Murine norepinephrine transporter gene (NET) has been mapped to a region on chromosome 8 where a quantitative trait locus for ethanol sensitivity. Therefore we tested whether norepinephrine transporter (NET) gene variants confer susceptibility to either alcohol dependence or severe alcohol withdrawal symptoms. There is a highly polymorphic silent G1287A mutation in the NET gene. In our study 157 alcoholics and 185 healthy unrelated matched control subjects were analyzed for a silent G1287A mutation. No significant differences in allele and genotype distribution between control subjects f(A)=0.33 and alcoholics f(A)=0.29 were found. No significant results were found in more homogenous subgroups, i.e. alcoholics with severe alcohol withdrawal (seizures, delirium), early onset age<26 nor dependent patients with positive familial history of alcoholism. These results suggest that the NET gene polymorphism in exon 9 accession number: mRNA: NM_001043, genomic contig.: NT_019610, is unlikely to be involved in the susceptibility to alcoholism and severe alcohol withdrawal.  相似文献   
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Traditional asthma education has been found to be time-consuming and limited in terms of availability. Our goal was to improve asthma care by meeting special needs of children with asthma and by building on their skills in using new technologies. Multimedia asthma education occurred through the viewing of short, animated vignettes on an exam room computer. Evaluation of 228 children showed significant improvement in days of asthma symptoms (p ??.01), in emergency room visits (p ??.05), in school days missed (p ??.05), and in days of activity limitation from baseline to the year-end follow-up (p ??.05). Effective multimedia education, if integrated into pediatric practice to supplement existing asthma care, can improve clinical outcomes.  相似文献   
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Involvement of chemokine receptor CCR6 in colorectal cancer metastasis.   总被引:2,自引:0,他引:2  
Various chemokine receptors, namely CXCR4, CCR6 and CCR7, have recently been shown to be involved in the regulation of metastasis in malignant tumors. However, little is known about the role of these receptors in promoting tumor metastasis of colorectal cancer (CRC) to the primary site of CRC metastasis in the liver. To investigate this issue, we analyzed the expression of the chemokine receptors CXCR4, CCR6 and CCR7 in colorectal tumors and colorectal liver metastases. In the present study, 30 human cancer samples from colorectal tissue, 30 human samples from colorectal liver metastases and the adjacent nontumorous liver tissues were screened using quantitative real-time PCR, Western blot analysis, histochemistry, microdissection and the enzyme-linked immunosorbent assay (ELISA). While an overexpression of all the chemokine receptors was found in CRC, in colorectal liver metastases only the chemokine receptors CXCR4 and CCR6 were significantly upregulated. Consequently, we investigated the expression of the corresponding ligands CXCL12/SDF1alpha, CCL20/MIP3alpha, CCL19/MIP3beta and CCL21/6Ckine in various organs, such as the stomach, esophagus, pancreas, colon and rectum, in comparison with their expression in the liver as the primary site of metastatic spread in CRC. We found that only CCL20 exhibits peak levels of expression in the liver, thus indicating that an increased production of CCL20 may contribute to the selective recruitment of CCR6-expressing cancer cells in CRC. Furthermore, we could demonstrate that CRC patients who developed liver metastases express significantly more CCL20 and CCL21 in the liver in comparison with an unaffected control group. Therefore, our findings strongly suggest an association between CCL20/CCR6 expression in human CRC and the promotion of colorectal liver metastasis.  相似文献   
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Background Vitreoretinal complications are rare in laser in situ keratomileusis (LASIK). Increase in intraocular pressure caused by intraoperative suction with subsequent deforming of the ocular globe and excimer laser shock during the ablation have been discussed as possible causes. The purpose of this study was to determine the effect of LASIK on the vitreous body. Patients and methods In a prospective study we performed ocular ultrasonography (B scan) immediately before and 1 week after LASIK procedure in 103 myopic or myopic–astigmatic eyes (53 patients, mean age 36.3 years, 32 women, 21 men). In particular, the prevalence, localization, and extent of posterior vitreous detachment (PVD) were determined. Results The mean spherical equivalent was −4.85 D (range −1.25 to −8.38) and the mean anteroposterior ocular globe length was 25.13 mm (range 23.31–27.65). Ninety-five eyes (92.2%) had no PVD preoperatively. Nine eyes out of this group (seven patients, 9.5%) developed incomplete PVD as assessed 1 week postoperatively. Eight eyes (7.8%) had a partial PVD preoperatively and in only one eye was an extension of vitreous detachment observed after the surgery. None of the preoperatively measured parameters could predict the occurrence of PVD by LASIK. Conclusions LASIK may in rare cases lead to new occurrence of PVD or extension of a previously existing partial PVD. Thomas Kohnen is a consultant for scientific advice to Bausch & Lomb, Inc., but neither author has a financial proprietary in any of the instrumentation or devices used in this study. This paper was presented in part at the German Ophthalmic Society (DOG) 2003 annual meeting, Berlin, with the title “LASIK-induced posterior vitreous detachment.”  相似文献   
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Purpose: Although the air-conduction pathway is the principal mode of sound transmission to the inner ear, this may not be true for the fetus in utero. The fetus detects and responds to sounds in the maternal environment. Exogenous sounds can reach the fetal inner ear through the ear canal and middle ear system, bone conduction, or both. This study was designed to compare the effectiveness of these two routes of sound transmission by recording cochlear microphonic potentials from the fetus in utero in response to airborne sounds.Materials and Methods: Cochlear microphonics (CMs) recorded from one round window (RW) of fetal sheep in utero were obtained in three conditions: (1) head uncovered; (2) head covered with a neoprene hood; and (3) head covered with a neoprene hood fashioned with a hole that permitted the pinna and ear canal to be exposed. Tone bursts (0.5, 1.0, and 2.0 kHz) were delivered through a loudspeaker at high intensities (100 to 135 dB sound pressure level) to the flank of the ewe. CMs were detected with indwelling electrodes, amplified, and averaged. CM input-output functions were obtained from the fetus in each of the three conditions described above.Results: CMs recorded with the head uncovered were more sensitive than were the CMs recorded with the hood in place. There was no difference in sensitivity between the condition during which the head was completely covered and the condition in which the pinna and ear canal canal are exposed.Conclusion: The principal mode of sound transmission into the fetal inner ear is through bone conduction.  相似文献   
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