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21.
PURPOSE: To report the accuracy of telemedical slit-lamp evaluation in examination of ocular adnexa and anterior segment. METHODS: By means of contingency tables, slit-lamp findings by live examination and by real-time telemedicine were compared in 50 eyes of 25 patients. RESULTS: Sensitivity percentages (proportion with findings correctly identified by telemedicine)/specificity percentages (proportion without the finding that was correctly identified by telemedicine) were 100/64 for eyelid mass, 100/85 for conjunctival pigment, 100/100 for posterior synechiae, 80/0 for blepharitis, 83/93 for iridotomy, 70/93 for pinguecula, 75/93 for iris lesions, 56/98 for corneal scar, 0/100 for chamber inflammation, 57/93 for nuclear cataract, and 37/100 for intraocular lens presence. CONCLUSIONS: By means of monocular slit-lamp telemedical evaluation, clinical findings with high contrast cues for color and depth have the highest sensitivity and specificity.  相似文献   
22.
We investigated the effects of prostaglandins on cyclic AMP (cAMP) levels and on the activity of the rate-limiting enzyme of melatonin biosynthesis, arylalkylamine-N-acetyltransferase (NAT). The study was performed on primary cultures of dispersed chick pineal cells. Prostaglandin E, (PGE,) increased cAMP levels 2-fold and this stimulation went up to 4-fold in the presence of a phosphodiesterase inhibitor. The PGE,- evoked increase in cAMP levels did not desensitize over 6 h. The potency order of a series of prostaglandins to increase cAMP levels (PGE1 PGE1>PGA2>PGD2?PGF2α) agreed with the pharmacological profile of the adenylate cyclase-coupled prostaglandin receptor. Inhibition of endogenous prostaglandin synthesis by two cyclooxygenase inhibitors (indomethacin and aspirin) caused a 30% decrease in cAMP levels. This effect was completely reversed by the addition of exogenous PGE1 or PGE2. Indomethacin and aspirin also caused a 50% decrease in NAT activity. Prostaglandins of the E series increased NAT activity up to 2-fold above basal level and restored NAT activity after inhibition by indomethacin or aspirin. These results are the first illustration of a role for prostaglandins in chick pineal cells. The correlations observed between cAMP levels and NAT activity suggest that the regulation of NAT activity by prostaglandins of the E series might be mediated by changes in cAMP concentration.  相似文献   
23.
OBJECTIVE: To describe the decline of vestibulocochlear function in a man with vestibulocochlear dysfunction caused by a Pro51Ser mutation within the COCH gene on chromosome 14q12-13 (DFNA9). METHODS: A follow-up of more than 15 years was performed in a single case. Clinical investigations were supplemented by oculomotor, vestibular, and auditory tests. RESULTS: A 50-year-old man had had progressive sensorineural hearing loss and dysequilibrium for 15 years; he had been asymptomatic at the age of 35 years. He suffered from instability in the dark, head movement-dependent oscillopsia, paroxysmal positional vertigo, and vertigo with and without nausea. Hearing impairment started unilaterally, predominantly in the high frequencies. He also reported tinnitus. Disease progressed to severe bilateral high-frequency hearing impairment and vestibular areflexia. Fluctuation of vestibulocochlear function was documented and mentioned by the patient. CONCLUSIONS: Our patient proved to suffer from an autosomal dominant vestibulocochlear disorder caused by a COCH gene mutation. The remarkable medical history has some features in common with Meniere disease; however, there are also different clinical and neurophysiological features. In the family, phenotypic variability is present.  相似文献   
24.
Higher fat and energy intakes confer a survival advantage in cystic fibrosis (CF). There is a need to develop effective nutrition programmes that ensure optimal energy intake in CF.

Methodology:


A cross-sectional measurement of clinical characteristics and energy and fat intakes in patients attending the CF outpatients clinic of the John Hunter Hospital, Newcastle was undertaken. Twenty-nine subjects, mean age 12 years (range 4.3–20.2), completed weighed food records to determine the contribution of fat to the percentage of the recommended energy intake obtained and to document use of pancreatic enzyme replacement therapy.

Results:


Diets with a high percentage of energy derived from fat did not guarantee that individuals with CF met their energy requirements. Subjects with total fat intakes of 100 g per day or greater, however, achieved in excess of 110% recommended daily intake (RDI) for energy. Up to 47% of subjects consumed more pancreatic enzyme replacement capsules than shown to give maximum effectiveness.

Conclusion:


Setting a 100 g daily fat target is a realistic way of ensuring high energy intakes in CF. Fat ready reckoners would identify the fat content of food and prescribe specific numbers of pancreatic enzyme replacement capsules to be consumed with each meal or food item.  相似文献   
25.
OBJECTIVES: To determine the spectrum of N and G genotypes of respiratory syncytial virus (RSV) causing respiratory tract infection and whether particular genotypes are associated with severity of infection. PATIENTS AND METHODS: Nasopharyngeal aspirates (NPAs) were obtained from 114 infants with acute respiratory tract infection due to RSV over two seasons. Viral mRNA was extracted from NPAs or cultured virus, reverse transcribed, and the cDNA amplified by the polymerase chain reaction using primers directed to parts of the N and G gene respectively. Amplicons were separately digested with four different restriction endonucleases for each gene. The fragments were separated by agarose gel, electrophoresis, and the electrophoretic patterns used to assign the various genotypes. Disease severity was assessed as very mild (upper respiratory tract signs only), mild (coryza and signs of lower respiratory tract infection), moderate (requiring nasogastric or intravenous fluids), and severe (requiring oxygen or ventilation). RESULTS: Five of the six known N genotypes were detected, but NP4 and NP2 were found most frequently. There was no association between N genotype and disease severity. Six G (SHL) genotypes were detected. Significantly (p = 0.04) more of the infants infected with the SHL2 genotype had severe or moderate disease. CONCLUSIONS: During the seasonal peaks of RSV respiratory tract infection at least 10 different RSV genotypes cocirculated. While there is no association between N genotypes and disease severity, infection with the SHL2 G genotype appears to result in moderate to severe disease.  相似文献   
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Targeted therapies that inhibit the activity of tyrosine kinase receptors such as the epidermal growth factor receptor (EGFR) have shown activity against solid malignancies when used as single agents or in combination with chemotherapy. Although anti-EGFR therapies are active in some patients, eventually disease in nearly all patients will become refractory to therapy. Therefore, a better understanding of the mechanisms of resistance to anti-EGFR therapies is critical to further improve the efficacy of this class of agents. Mechanisms that mediate resistance to anti-EGFR therapies include the presence of redundant tyrosine kinase receptors, increased angiogenesis, and the constitutive activation of downstream mediators. Two recent landmark publications have also shown that specific mutations in the kinase domain of EGFR in some lung carcinomas are associated with markedly improved response rates to an EGFR tyrosine kinase inhibitor. Mutations in the EGFR receptor seem to play a significant role in determining the sensitivity of tumor cells to EGFR inhibitor therapy by altering the conformation and activity of the receptor. As the field of molecular therapeutics continues to evolve, a comprehensive understanding of resistance mechanisms will ultimately lead to refinements in our regimens to provide better care for patients with cancer.  相似文献   
30.
BACKGROUND: The current tumor-node-metastasis system is inadequate to accurately classify patients in terms of prognosis. Thus, with the availability of recently developed molecular tools, considerable interest lies in discovering prognostic markers in order to guide treatment decisions. In this study, we sought to determine the prognostic significance of the cell cycle regulator cyclin D1 in oropharyngeal squamous cell carcinoma (OSCC). EXPERIMENTAL DESIGN: We studied the protein expression levels of cyclin D1 on a tissue microarray composed of 63 OSCCs with long-term follow-up data available. Protein expression was analyzed with an automated in situ quantitative (AQUA) method which allows preservation of tissue morphology while quantifying protein expression in paraffin-embedded tissue. RESULTS: The mean follow-up time was 35 months. High cyclin D1 nuclear expression was associated with increased 5-year local recurrence rate (48% versus 15%), inferior 5-year disease-free survival (16% versus 58%), and inferior 5-year overall survival (17% versus 53%). In multivariate Cox regression, high nuclear cyclin D1 expression was an independent predictor for local recurrence, disease-free survival, and overall survival at 5 years. CONCLUSIONS: Our results indicate that quantitative assessment of nuclear cyclin D1 expression level by automated in situ quantitative analysis is a strong predictor for outcome in OSCC. Thus, cyclin D1 may be a potential target for molecular intervention in patients with oropharyngeal squamous cell cancer.  相似文献   
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