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991.
992.
HYPOTHESIS: To investigate the feasibility of gene therapy of the middle ear mucosa using a novel vector. BACKGROUND: Given present medications are unable to affect chronic otitis media, cholesteatoma, or tympanic membrane perforation, newer methods of treatment like gene therapy for these diseases must be explored. These genes can then be used to alter cytokines in the middle ear, slow or stop cholesteatoma growth, or improve tympanic membrane perforation healing. Feline immunodeficiency virus (FIV), a new lentiviral vector has been found to have greater than 90% efficiency in transfecting epithelial cells. Therefore, in vivo gene therapy of middle ear mucosa cells was attempted. METHODS: Twenty microliter of 5x10(5) vectors per ml FIV carrying the gene for green fluorescence protein (GFP) was introduced into the middle ears of Sprague-Dawley rats via a bulla approach. RESULTS: Expression of the GFP gene was observed in the middle ear mucosa cells at 1 week post-inoculation indicating transfection. CONCLUSION: Gene therapy of the middle ear is feasible with a FIV-based vector.  相似文献   
993.

Objective

Atopic dermatitis (AD) is the most common chronic relapsing skin disease seen in infancy and childhood. The intestinal microbiota play an important role in immune development and may play a role in the development of allergic disorders. Manipulation of the intestinal microbiota by synbiotics may therefore offer an approach to the prevention or treatment of AD and allergic diseases. We studied the clinical and immunologic effects of a new symbiotic (a mixture of seven probiotic strains of bacteria and Fructooligosaccharide) in infants and children with AD.

Methods

In a randomized, double-blind, placebo-controlled study, 40 infants and children aged 3 months to 6 years with AD received either a synbiotic or placebo for 8 weeks. The Severity Scoring of Atopic Dermatitis (SCORAD) index was recorded at baseline and also at 4 and 8 weeks of treatment.

Findings

There was no significant difference between the probiotic and placebo group in baseline characteristics including sex, age, family history, corticosteroid usage and prick testing. Mean age was 23 months. The synbiotic group showed a significantly greater reduction in SCORAD than did the placebo group (P=0.001). No specific effect was demonstrated of the probiotics employed on cytokine profile (P=0.4, P=0.6). Egg white was the most common (45%) allergen followed by peanut and cow''s milk.

Conclusion

This study provides evidence that a mixture of seven strains of probiotics and Fructooligosaccharide can clinically improve the severity of AD in young children. Further studies are needed to investigate the effects on underlying immune responses and the potential long term benefits for patients with AD.  相似文献   
994.
995.
The Helicobacter pylori infection rate was determined in 124 consecutive patients with duodenal ulcers (DU), gastric ulcers (GU), duodenal erosions or gastric erosions diagnosed by endoscopy at a single institution in north-eastern peninsular Malaysia in 1996-97. Biopsies of the gastric antrum and body were subjected to the urease test, Gram staining of impression smears, culture and histopathological examination. Serology was undertaken on all patients using a locally validated commercial kit. Infection was defined as a positive result in at least one test. The infection rates were 20% (10/50), 21.2% (7/33), 16.7% (1/6) and 17.1% (6/35) in DU, GU, duodenal erosion and gastric erosion patients, respectively. The infection rate among Malays [7.0%, (6/86)] was lower than in non-Malays [47.4% (18/38)] (P < 0.001). There was a higher infection rate among males, who constituted 62.1% (77/124) of the sample. Seventy-eight patients (62.9%) were receiving non-steroidal anti-inflammatory drugs (NSAIDs) and 33 patients (26.6%) were neither receiving NSAIDs nor were infected with H. pylori. The H. pylori infection rate among peptic ulcer patients in this predominantly Malay rural population appears to be the lowest reported in the world thus far. Empirical H. pylori eradication therapy in peptic ulcer patients is clearly not indicated in this community. The possible reasons for the low prevalence of H. pylori infection are discussed.  相似文献   
996.
A 1H NMR procedure for the monitoring of ampicillin (Amp) and its main related substance in different media, has been developed. The characteristics peak of Amp, 6-aminopenicillanic acid (6-APA), phenylglycine (PhG), and penicilloic acid in the range of 0.5-0.9 and 3.0-4.5 ppm were used for their identification in drugs and serum samples. The quantitative works were performed based on the intensity of protons of the methyl group link to the beta-lactam cyclic of Amp and 6-APA and the aromatic protons of PhG relative to the protons of methylene group of maleic acid, as internal standard, at constant temperature. The resulting data are compared with those obtained with an HPLC method proposed by British Pharmacopoeia. Statistical studies show that, at a confidence limit of %95, there is no significant difference between the two methods. In comparison with the HPLC method, the proposed NMR method does not require any sample pretreatment, standard solution preparation, long analysis time and use of any carcinogenic solvent. The method was applied to the determination of Amp and its related substances in synthetic mixtures, drug powders and serum samples.  相似文献   
997.
We describe a patient with proliferative diabetic retinopathy who had laser in situ keratomileusis (LASIK). Rapid progression and pronounced aggravation of diabetic retinopathy occurred after LASIK, resulting in severe visual loss in both eyes.  相似文献   
998.
Neurophysiological processes underlying auditory memory and attention are impaired in habitually short sleepers. The aim of this study was to use dynamic causal modeling (DCM) to study the mechanisms of these impairments in short sleepers. Eight normal sleepers (total sleep time (TST)=7-8h) and nine habitual short sleepers (TST≤6h) participated. The time in bed was increased from habitual (≤6h) to extended (~8.5h) for one week in the short sleep group. Event related potentials (ERPs) were collected using an auditory novelty task in "IGNORE" and "ATTEND" conditions. Fourteen DCM models were considered using different configurations of connections among the following six areas: left and right primary auditory cortices, superior temporal gyri (STG), and inferior temporal gyri (IFG). After fitting the ERPs to the 14 models (separately for the IGNORE and ATTEND conditions), the best model (across subjects) was chosen using the Bayesian model comparison. For both conditions, the connection from right-STG to right-IFG for normal sleepers was significantly greater than habitual short sleepers. This connection did not differ in habitual short sleepers before and after one week of extended sleep time. This connection for normal sleepers was not significantly greater than the habitual short sleepers after one week of extended sleep. These results show that the deficiency of novelty processing, seen in short sleepers, can be explained by the differences in connectivity of the pathway between frontal and temporal brain areas as compared to the normal sleepers. In addition, one week of extended time in bed was not enough to fully normalize this neuronal pathway between STG and IFG in short sleepers.  相似文献   
999.
Goals and objectivesThis study was designed to evaluate the effects of exogenous Sodium-Hyaluronate (NaH) on full thickness Superficial Digital Flexor Tendon (SDFT) rupture in the early phase of healing in rabbits.MethodsForty White New Zealand mature male rabbits were randomly divided into two equal groups of injured treated and injured untreated. After full thickness tendon transection and surgical repair, using modified Kessler technique and running suture, the injured legs were casted for 14 days. Sodium-Hyaluronate was injected subcutaneously over the lesion on days 3, 7 and 10 post-injury (DPI). The control animals received normal saline injection following the same protocol. Weight of the animals, tendon diameter, ultrasonographic evaluations was conducted at weekly intervals. The rabbits were euthanized on 28 DPI and the tendons were assessed for macroscopic, histopathologic, ultrastructural, and percentage dry weight analysis.ResultsAlthough there was no significant difference in the radiographs of the treated and untreated lesions, treatment significantly reduced tendon diameter, ultimate and yield strain and increased echogenicity and dry weight content of the injured tendons compared to those of the untreated ones. Treatment also significantly enhanced the maturation rate of the tenoblasts, diameter and density of the collagen fibrils.ConclusionTreatment of NaH has been shown to be effective in restoring the morphological and biomechanical properties of lacerated SDFT of rabbits and may be valuable in the clinical trial studies.  相似文献   
1000.
Bioluminescence Tomography attempts to quantify 3-dimensional luminophore distributions from surface measurements of the light distribution. The reconstruction problem is typically severely under-determined due to the number and location of measurements, but in certain cases the molecules or cells of interest form localised clusters, resulting in a distribution of luminophores that is spatially sparse. A Conjugate Gradient-based reconstruction algorithm using Compressive Sensing was designed to take advantage of this sparsity, using a multistage sparsity reduction approach to remove the need to choose sparsity weighting a priori. Numerical simulations were used to examine the effect of noise on reconstruction accuracy. Tomographic bioluminescence measurements of a Caliper XPM-2 Phantom Mouse were acquired and reconstructions from simulation and this experimental data show that Compressive Sensing-based reconstruction is superior to standard reconstruction techniques, particularly in the presence of noise.OCIS codes: (170.3010) Image reconstruction techniques, (170.6280) Spectroscopy, fluorescence and luminescence, (170.6960) Tomography  相似文献   
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