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81.
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
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Juri V. Kaude M.D. James D. McDowall Charles L. Neustein Edward R. Woodward Patricia G. Wright 《Abdominal imaging》1981,6(1):135-140
Eighty patients who had undergone jejunoileal bypass for morbid obesity were examined by ultrasound at their routine follow-up visits to the clinic. Ultrasonographic evidence of intestinal intussusception was found in 15 patients (19%). Two of these patients were asymptomatic. Ultrasonographic findings were confirmed by operation in 6 patients (5 with intussusception, 1 negative). 相似文献
85.
P A Brioschi P Bischof C Delafosse F Krauer 《International journal of cancer. Journal international du cancer》1991,47(3):376-379
The serum concentration of squamous-cell carcinoma antigen (SCC-A), a subfraction of tumour antigen, was determined by RIA from healthy donors (control group) and from patients with malignant cervical disease. Ninety-six percent (173/180) of the healthy patients had squamous-cell carcinoma antigen serum levels below 2 ng/ml. Ten of 70 (14.3%) patients with CIN III, 53.8% (34/62) of patients with invasive squamous-cell carcinoma stage I, 85.8% (30/35) with stage II and 96.5% (27/28) with stage III/IV had squamous-cell carcinoma antigen serum levels above 2 ng/ml. We observed that 22.5% (11/49) of patients with a tumour volume below 10 ml and 92.6% of patients with a tumour volume greater than 10 ml had squamous-cell carcinoma antigen levels above 2 ng/ml (p less than 0.005). SCC-A was correlated with recurrence or progressive disease in 90.0% of cases. Other risk factors such as depth of invasion, microscopic parametrial involvement, lymphatic and/or vascular space permeation and histological grade were not correlated with squamous-cell carcinoma antigen. Furthermore, this marker increased 4.3 +/- 2.7 months before clinical evidence of recurrence or progressive disease. We conclude that serial serum levels of squamous-cell carcinoma antigen provide a means for early detection of recurrence or progressive disease. This tumour marker might also be useful for monitoring the treatment effects and has some prognostic value. 相似文献
86.
Patricia P Katz Edward H Yelin Mark D Eisner Paul D Blanc 《Annals of allergy, asthma & immunology》2002,89(3):251-258
BACKGROUND: Perceived control of certain chronic conditions influences health status outcomes. OBJECTIVE: To explore the impact of perceived control of asthma on asthma-specific and generic health status outcomes among adults with asthma. Perceived control was defined as individuals' perceptions of their ability to deal with asthma and its exacerbations. METHODS: Data were drawn from the baseline and first two followups of a longitudinal study of adults with asthma surveyed by telephone at 18-month intervals. An 11-item questionnaire (Perceived Control of Asthma Questionnaire [PCAQ]) was developed and validated. RESULTS: The PCAQ demonstrated high internal consistency (Cronbach's alpha = 0.79). Greater perceived control was associated with less severe asthma, greater asthma self-efficacy, lower perceived asthma severity, lower perceived danger from asthma, and greater perceived usefulness of asthma medicines. Greater perceived control was significantly associated with better asthma-specific quality of life concurrently and 18 and 36 months later, after controlling for demographics, smoking, and severity of asthma. Greater perceived control as also significantly associated with generic mental health outcomes concurrently and 18 and 36 months later, after controlling for covariates. Perceived control was associated with physical function concurrently and 18 months later, but not 36 months later. CONCLUSIONS: The PCAQ is a reliable and valid measure of perceived control of asthma. Perceived control of asthma was associated with both asthma-specific and generic health status outcomes, concurrently and predictively. If perceived control could be modified, better outcomes, particularly better psychologic outcomes, might be achieved for individuals with asthma. 相似文献
87.
Individuals and families with hereditary cancers have informational needs that differ, depending on the availability of testing for increased hereditary risk and major focus of concern (reproductive decision-making or risk to self). Cancer risk counseling helps individuals understand risk information so they can make decisions appropriate to their lives and value systems. 相似文献
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Manuel Diaz-Llopis Salvador García-Delpech David Salom Patricia Udaondo Francisco Bosch-Morell Arturo Quijada Francisco J Romero Luis Amselem 《Journal of ocular pharmacology and therapeutics》2007,23(4):343-350
PURPOSE: The aim of this study to analyze the preventive effect of high-dose infliximab in endotoxin-induced uveitis (EIU) in rabbits. METHODS: An experimental study was conducted on 64 rabbits. Salmonella typhimurium lipopolysaccharide endotoxin was intravitreally injected. Infliximab was intravenously (i.v.) injected 24 h before the intravitreal injection (20 mg/kg). The animals were randomly assigned to five groups: group A, saline intravitreal injection; group B, Infliximab i.v. group C, infliximab + saline; group D, intravitreal endotoxin and group E, infliximab i.v. + intravitreal endotoxin. With two masked observers, a microscopic examination of aqueous humor (cells, tumor necrosis factor [TNF] alpha) and aqueous protein level were performed 24 h after an endotoxin injection and 48 h after an infliximab infusion. RESULTS: Infliximab treatment, at a dose of 20 mg/kg, significantly improved all the parameters. Inflammatory cell infiltration was significantly reduced in the iris, ciliary body, and anterior chamber (U Mann-Whitney test, P = 0.01). Associated with a lower level of TNF-alpha and protein exudate in aqueous humor (U Mann-Whitney test, P = 0.01). CONCLUSIONS: Infliximab, at a dose of 20 mg/kg, is effective in the prophylaxis of the EIU. 相似文献
90.
Akio Tanaka Motoyoshi Okamoto Dai Yoshizawa Shigeru Ito Patricia González Alva Fumio Ide Kaoru Kusama 《Journal of oral pathology & medicine》2007,36(7):400-404
BACKGROUND: Although it has been reported that ghost cells are present in odontomas, the generation mechanism of these cells is unclear. To evaluate the presence of ghost cells and involvement of the Wnt signaling pathway, we examined the expression of hard keratins, beta-catenin and Lef-1 in odontomas. METHODS: Sixty-nine cases of odontoma were examined immunohistochemically with the use of antibodies against human hair proteins, beta-catenin and Lef-1. RESULTS: Expression of hard keratins was found only in the cytoplasm of ghost cells in 46 (66.7%) of the 69 odontomas. Compound odontomas (78.8%) showed a higher incidence of ghost cells than complex odontomas (29.4%). Histopathologically, ghost cells were found within odontogenic epithelium adjacent to immature enamel and in the centre of Liesegang-ring-like calcified materials. Expression of beta-catenin and Lef-1 was observed in the cytoplasm and nucleus of odontogenic epithelial cells adjacent to the ghost cells in immature odontomas. CONCLUSION: These findings suggest that odontoma is a hard keratin-expressing tumor-like lesion, and that the Wnt signaling pathway may be involved in the formation of ghost cells in odontomas. 相似文献