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排序方式: 共有579条查询结果,搜索用时 15 毫秒
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Otavio B Piltcher J Douglas Swarts Karin Magnuson Cuneyt M Alper William J Doyle Patricia A Hebda 《Otolaryngology--head and neck surgery》2002,126(5):490-498
OBJECTIVE: To describe the clinical and histopathologic progression of a rat model of otitis media with effusion caused by eustachian tube obstruction (ETO) with and without Streptococcus pneumoniae infection. METHODS: In 164 rats, the left, bony eustachian tube was approached via a ventral incision and obstructed with dental material. Then 108 rats were infected via an intrabullar injection with S pneumoniae. At 48 hours, the infected rats were treated for 5 days with ampicillin. All ears were evaluated by weekly otomicroscopy. On each of days 1, 2, 7, 21, 35, 56, and 112, four rats were killed for histologic study. All effusions were cultured for bacteria. RESULTS: Fourteen rats died of surgical complications; effusion resolved by 2 weeks in 9 rats. During the first few days, infected ears with ETO had bulging tympanic membranes, followed by tympanic membrane retraction, purulent effusion, and otorrhea (50%) over the next few weeks, whereas uninfected ears with ETO developed retraction and serous effusion during the same time frame. At later times, all ears with ETO presented with retraction and serous or serous-mucoid effusion. S pneumoniae was recovered only from the infected ears with ETO (days 1 and 2), with some colonization by nonpathogenic microorganisms observed equally in both groups of ears. Histology showed a typical acute inflammatory reaction in the challenged ears with ETO through day 14 and then a chronic inflammation for all ears with ETO. CONCLUSION: The experimental methods provoked reproducible pathologic signs similar to those for otitis media with effusion. Given the availability of rat-specific reagents, this model is well suited for studies of cytokine elaboration during disease pathogenesis. 相似文献
3.
Deborah M Antonino-Green Jianguo Cheng David S K Magnuson 《The Journal of comparative neurology》2002,442(3):226-238
Spinal cord/brainstem preparations from 5- to 8-day-old rats, maintained in vitro, were used to determine the cells of origin and regions of termination of fibers in the superficial ventrolateral funiculus (VLF) at a site from which rhythmic locomotor-like activity can be induced. Rhythmic locomotor-like activity was recorded from lumbar ventral roots after short trains of stimuli (50 Hz for 0.5-2 seconds) delivered to the VLF. Field potential mapping revealed that single VLF stimuli elicited responses in the ipsilateral ventrolateral medulla. Tract-tracing experiments by using biocytin, pressure-injected into the VLF, showed that only a small number of brainstem neurons were labeled and these were scattered bilaterally in the ventrolateral and lateral medulla. Dense concentrations of nerve terminals were found in the lateral reticular nucleus ipsilateral to the stimulation site. Labeled spinal cord neurons included a primary population of large cells distributed bilaterally in lamina VII from T13 to L4, with peak numbers in L2 ipsilaterally and in L3 contralaterally. Intracellular recordings revealed that some L2 and L3 neurons with rhythmic responses to VLF stimulation could be activated antidromically from the VLF, with latencies of less than 1.0 msec. These observations led us to speculate that the superficial VLF carries a locomotor-related tract originating bilaterally in lumbar lamina VII and terminating in the ipsilateral medulla, including the lateral reticular nucleus. This pathway may be part of the spinoreticular or spinoreticulotectal pathway that has been described in many species, the function of which has only loosely been ascribed. 相似文献
4.
Thierbach R Schulz TJ Isken F Voigt A Mietzner B Drewes G von Kleist-Retzow JC Wiesner RJ Magnuson MA Puccio H Pfeiffer AF Steinberg P Ristow M 《Human molecular genetics》2005,14(24):3857-3864
We have disrupted expression of the mitochondrial Friedreich ataxia protein frataxin specifically in murine hepatocytes to generate mice with impaired mitochondrial function and decreased oxidative phosphorylation. These animals have a reduced life span and develop multiple hepatic tumors. Livers also show increased oxidative stress, impaired respiration and reduced ATP levels paralleled by reduced activity of iron-sulfur cluster (Fe/S) containing proteins (ISP), which all leads to increased hepatocyte turnover by promoting both apoptosis and proliferation. Accordingly, phosphorylation of the stress-inducible p38 MAP kinase was found to be specifically impaired following disruption of frataxin. Taken together, these findings indicate that frataxin may act as a mitochondrial tumor suppressor protein in mammals. 相似文献
5.
W E McAuliffe M Rohman S Santangelo B Feldman E Magnuson A Sobol J Weissman 《The New England journal of medicine》1986,315(13):805-810
We surveyed random samples of 500 practicing physicians and 504 medical students in a New England state during 1984-1985; 70 percent of the physicians and 79 percent of the students responded. Fifty-nine percent of the physicians and 78 percent of the students reported that they had used psychoactive drugs at some time in their lives. In both groups, recreational use most often involved marijuana and cocaine, and self-treatment most often involved tranquilizers and opiates. In the previous year, 25 percent of the physicians had treated themselves with a psychoactive drug, and 10 percent had used one recreationally. Although most of the use was experimental or infrequent, 10 percent of the physicians reported current regular drug use (once a month or more often) and 3 percent had histories of drug dependence. More physicians and medical students had used psychoactive drugs at some time than had comparable samples of pharmacists and pharmacy students. The results suggest a need for renewed professional education about the risks of drug misuse. 相似文献
6.
A D Weinberg J Shaw V Paetkau R C Bleackley N S Magnuson R Reeves J A Magnuson 《Immunology》1988,63(4):603-610
We have cloned the Tac analog of the bovine IL-2 receptor (IL-2R) cDNA. Using mouse and human cDNA probes, we isolated five bovine IL-2R clones from a lambda gt11 bovine long-term lymphocyte cDNA library. Three of the clones had inserts of 2600 base pairs (bp), the same size as the bovine IL-2R mRNA visualized on Northern blots. The full-length cDNA contain a 190-bp 5' untranslated region, followed by a 825-bp coding region, and a 3' untranslated region that contain 1600 bp. Comparison of the bovine and human IL-2R-coding sequences revealed 71% homology at the nucleotide level. The 3' and 5' non-coding regions were not as homologous, apart from a specific site in the 5'-untranslated region that contained a 5'-upstream start codon. In this region, 24 of 26 nucleotides were identical for the human and bovine cDNAs. Further analysis of the bovine IL-2R sequence also revealed the following: (i) the hydrophobic domains of the IL-2R protein were more conserved between species than the hydrophilic domains, (ii) the predominant site of intracellular IL-2R phosphorylation in mouse and human was a conserved Ser which was not conserved in the bovine sequence, and (iii) there exists a statistically significant amino acid homology with the AIDS gag protein. 相似文献
7.
Kah Poh Loh Jason Zittel Sindhuja Kadambi Chintan Pandya Huiwen Xu Marie Flannery Allison Magnuson Javier Bautista Colin McHugh Karen Mustian William Dale Paul Duberstein Supriya G. Mohile 《Journal of Geriatric Oncology》2018,9(5):464-468
Objectives
Sleep disturbance is prevalent and often coexists with depression, fatigue, and pain in the cancer population. The aim of this study was to describe the prevalence of sleep disturbance with co-existing depression, fatigue, and pain in older patients with cancer. We also examined the associations of several socio-demographic and clinical variables with sleep disturbance.Methods
This cross-sectional study consisted of 389 older patients with solid and hematologic malignancies who were referred to the Specialized Oncology Care & Research in the Elderly (SOCARE) clinics at the Universities of Rochester and Chicago between May 2011 and October 2015 and completed a sleep and geriatric assessment (that inquires about fatigue, pain, and depression). Multivariate logistic regression was used to identify variables associated with sleep disturbance.Results
The prevalence of sleep disturbance was 40%. Of those with sleep disturbance (n?=?154), 84% also had at least one of the other three symptoms (25% had one symptom, 38% had two symptoms, and 21% had three symptoms). Sleep disturbance was more likely to be reported in those with comorbidities (45% vs. 28%, P?=?0.002), depression (49% vs. 36%, P?=?0.015), fatigue (49% vs. 23%, P?<?0.001), and pain (45% vs. 31%, P?=?0.010). On multivariable analysis, only fatigue (adjusted odds ratio (AOR) 1.90, 95% CI 1.10–3.30, P?=?0.020) was independently associated with sleep disturbance.Conclusions
Sleep disturbance is prevalent and often co-occurs with depression, fatigue, or pain in older patients with cancer. Fatigue was significantly associated with sleep disturbance and future studies should explore interventions that target sleep disturbance and fatigue. 相似文献8.
Damir Malmvind Alja Gole Anders Magnuson Maja Ovsenik Farhan Bazargani 《The Angle orthodontist》2022,92(5):589
ObjectivesTo assess and compare the three-dimensional treatment changes in palatal surface area and volume using either tooth-borne (TB) or tooth bone–borne (TBB) rapid maxillary expanders and to evaluate the long-term effects of the two devices and the incidence of the relapse between the groups.Materials and MethodsA total of 52 consecutive patients who met the eligibility criteria were recruited and allocated to either the TB group, mean age 9.3 years (standard deviation [SD], 1.3), or the TBB group, mean age 9.5 years (SD, 1.2). Study casts were taken before, directly after, 1 year after, and 5 years after expansion. Study casts were digitized, superimposed, and evaluated. Participants were randomly allocated in blocks of different sizes using the concealed allocation principle in a 1:1 ratio.ResultsChanges in palatal volume, palatal surface area, and palatal projection area within and between the groups up to 5 years after expansion followed the same pattern and did not show any statistically significant differences between the groups. Relapse was seen in 15% of the patients. It seemed that open-bite and a Class III growth pattern could be assumed as prognosis-deteriorating factors in regard to stability of the treatment.ConclusionsThere were no significant differences between the TB and TBB groups in palatal volume, palatal shell area, or palatal projection area directly after expansion or at 1 year and 5 years after expansion, which implies that the two devices gave rise to the same immediate and long-term outcomes. 相似文献
9.
Harry Eagle H. J. Magnuson Ralph Fleischman 《The Journal of experimental medicine》1947,85(4):423-440
1. A relatively small amount of penicillin sufficed to abort syphilitic infection in rabbits when administered during the incubation period of the disease. 2. The abortive dose, given as a single intramuscular injection in oil and beeswax, varied with the age of the infection. (a) With a fixed intratesticular inoculum, the amount of penicillin necessary to prevent infection in half the animals remained at a constant level for 4 days. By the end of the 2nd week more than seven times this dosage was needed; and by the 6th week, after the chancre had appeared, more than thirty times the amount was needed to obtain the same result. The progressive increase in the abortive dose of penicillin with the passage of time probably reflects the interim multiplication of organisms. (b) Qualitatively similar results were obtained in rabbits inoculated intracutaneously. 3. The abortive dose varied also with the size of the inoculum. In animals inoculated intracutaneously with 20, 2,000, and 200,000 spirochetes, and treated 4 days later, it required 200, 500, and 3,500 units per kg., respectively, to protect half the animals, and the corresponding PD90 dosages were 500, 2,000, and 16,000 units per kg. 4. The present observations, indicating the ease of aborting experimental rabbit syphilis during the incubation period by a single injection of penicillin, are perhaps applicable to the prevention of the disease in man. 5. Asymptomatic infections were rare in animals receiving inadequate doses of penicillin during the incubation period. Sixty-four of sixty-five such animals developed darkfield-positive lesions at the inoculated site. In animals treated 6 weeks after inoculation, however, after the development of lesions, inadequate treatment was usually manifested by an asymptomatic redissemination of organisms demonstrable only by lymph node transfer. The difference in the two groups probably reflects the beginning development of immunity in the rabbits treated 6 weeks after inoculation. 6. As suggested by Rake and Dunham (11), the treatment of animals during the incubation period permits a rapid assay of antisyphilitic agents, and one which requires only small amounts of material. Possible limitations of the method are discussed in the text. 相似文献