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1.
PURPOSE: To describe data sources and functional utility of the American Association for Pediatric Ophthalmology and Strabismus (AAPOS) workforce database and associated map files. METHODS: Population data from the 2000 U.S. Census and current listings from the AAPOS and American Academy of Ophthalmology (AAO) databases were organized to demonstrate and analyze practitioner-to-population relationships for metropolitan statistical areas nationwide. An interactive map was developed to provide an intuitive graphical display of the data. RESULTS: A total of 749 active AAPOS members were distributed in 154 of 280 defined metropolitan statistical areas. Within these areas, a 0- to 20-year age subgroup varied from 17.8% to 42.6%, with an average of 30.4%. The AAPOS member-to-million-person ratio varied from 1.3 to 27, with higher numbers generally representing regions with population bases inadequately defined by Census Bureau statistical area definitions. Ratios for a majority of larger, better-defined areas ranged from 3 to 4 AAPOS members per million persons. Sizable areas with no AAPOS member presence were identified and tabulated. AAO members with a specified pediatric practice focus who were not AAPOS members were identified in 103 areas, possibly influencing patient choices and practitioner referrals for these regions. CONCLUSIONS: The AAPOS workforce database and related interactive map display practitioner and population data that may assist physicians and planners in targeting practice development and identifying potentially underserved areas.  相似文献   
2.
The effect of single and repeated UVB radiation on rabbit cornea   总被引:1,自引:0,他引:1  
Background Cumulative effect of ultraviolet radiation (UVR) is an important aspect of UV corneal damage. The purpose of this study was to apply high resolution magic angle spinning proton nuclear magnetic resonance (HR-MAS 1H NMR) spectroscopy to evaluate the effect of single and repeated UV radiation exposure of the same overall dose on the rabbit cornea.Methods Corneal surfaces of 24 normal rabbit eyes were examined for the effects of UVB exposure (312 nm). In the first group (UVB1), animals were irradiated with a single dose (3.12 J/cm2; 21 min) of UVB radiation. The animals in the second group (UVB2) were irradiated three times for 7 min every other day (dose of 1.04 J/cm2; days 1, 3, 5) to give the same overall dose (3.12 J/cm2). The third group served as an untreated control group. One day after the last irradiation, the animals were sacrificed, and the corneas were removed and frozen. HR-MAS 1H NMR spectra from intact corneas were obtained. Special grouping patterns among the tissue samples and the relative percentage changes in particular metabolite concentrations were evaluated using modern statistical methods (multivariate analysis, one-way ANOVA).Results The metabolic profile of both groups of UVB-irradiated samples was significantly different from the control corneas. Substantial decreases in taurine, hypo-taurine and choline-derivatives concentrations and substantial elevation in glucose and betaine levels were observed following the UVR exposure. There was no significant difference between the effect of a single and repeated UVB irradiation of the same overall dose.Conclusions For the first time, the effects of single and repeated UVR doses on the metabolic profile of the rabbit cornea were analysed and compared. The combination of HR-MAS 1H NMR spectroscopy and modern statistical methods (multivariate analysis, one-way ANOVA) proved suitable to assess the overall view of the metabolic alterations in the rabbit corneal tissue following UVB radiation exposure.  相似文献   
3.
The previously observed occurrence of antineutrophil cytoplasmic autoantibodies (ANCA) in patients who have cystic fibrosis (CF), together with the reported decrease in IgG2, a Th1-controlled isotype, suggests a potential for Th1/Th2 imbalance in CF patients with a possible Th2 predominance. 48 CF patients and 16 controls had levels of IFNgamma, IL-4, and IL-10 measured in supernatants of whole blood cell cultures stimulated by lipopolysaccharide (LPS) and phytohemaglutinine (PHA). The patients were divided into 2 groups: "low responders", having negligible secretion of cytokines (IFNgamma: 10.0-200.0 pg/ml, IL-4: 0.0-0.3 pg/ml) and "high responders", producing high levels of both IFNgamma (500.0-2000.0 pg/ml) and IL-4 (1.0-200.0 pg/ml). There was a statistically significant (P < 0.01) deterioration of lung function measured by an FEV(1) decline by 11.2% over 3 years in the "low responder" group. 10 of 16 "low responders" had chronic lung infections with P. aeruginosa while such infection was less prevalent in the "high responder" group where only 13 of 32 CF patients had positive cultures. A shift towards Th2 response was observed in the "high responder" group as children chronically infected with P. aeruginosa had greater IL-4 production than non-infected CF patients within the same cohort. ANCA autoantibodies were found only in the "high responder" group. Th2 immune response predominance in a subset of CF patients is associated with chronic P. aeruginosa infection.  相似文献   
4.
The inhibition of butyrylcholinesterase activity in human serum by protoberberine, benzophenanthridine and aporphine alkaloids as well as four model compounds has been studied. The mechanism of the inhibition is discussed on the basis of the different types of interaction of these compounds with butyrylcholinesterase and acetylcholinesterase.  相似文献   
5.
PURPOSE: Many cancer lines are methionine dependent and decrease proliferation when methionine supply is limited. Methylenetetrahydrofolate reductase (MTHFR) generates the folate derivative for homocysteine remethylation to methionine. We investigated the effect of antisense-mediated inhibition of MTHFR on survival of human cancer cells. EXPERIMENTAL DESIGN: We examined the in vitro and in vivo anticancer effects of a combination of MTHFR antisense and standard cytotoxic drugs. RESULTS: Specific antisense against MTHFR (EX5) showed significant inhibitory effects on growth of human colon, lung, breast, prostate, and neuroblastoma tumor cells in vitro compared with that of the control oligonucleotide. Cytotoxic drugs (5-fluorouracil, cisplatin, or paclitaxel) potentiated the effect of EX5. In vivo, antisense alone or in combination with cytotoxic drugs inhibited the growth of human colon and lung carcinoma xenografts. In comparison with control oligonucleotide, treatment with EX5 inhibited growth of colon tumors and lung tumors by 60% and 45%, respectively. EX5 with 5-fluorouracil decreased growth of colon tumors by an additional 30% compared with EX5 alone, and EX5 with cisplatin decreased growth of lung tumors by an additional 40% compared with cisplatin alone. Growth inhibition by EX5 was associated with decreased amounts of MTHFR protein and with increased amounts of an apoptosis marker. CONCLUSIONS: Our results confirm that MTHFR inhibition decreases tumor growth and suggest that inhibition of MTHFR by antisense or small molecules may be a novel anticancer approach.  相似文献   
6.
Sanguinaria canadesis, Chelidonium majus and Macleya cordata have been used for centuries as alternative medicines. Currently the extracts from these medicinal plants are components of veterinary and human phytopreparations, and of oral-hygiene agents. Sanguinarine and chelerythrine (SA/CHE) are biologically active components of these extracts. They display distinct antibacterial and anti-inflammatory properties, but, on the other hand, they have been reported as having adverse effects - genotoxicity and hepatotoxicity. This paper is aimed at evaluation of the effects of daily administration of the extract from Macleya cordata (2 mg and 100 mg in 1 kg feed, sanguinarine:chelerythrine 3:1) in the diet on the health status of swine. After 90-day administration, alkaloids were retained to a different extent in tissues. The highest SA/CHE retention was detected in the gingiva (0.55 microg/g) and liver (0.15 microg/g), no SA/CHE were detected in muscles. Plasma SA levels attained 0.11 microg/ml. Treated animals did not display any results of hematological, biochemical or histological assay different from controls. A (32)P-postlabeling assay proved that no DNA-adducts with SA/CHE were detected in pig livers. We did not observe any symptom linked to epidemic dropsy syndrome often attributed to sanguinarine. In conclusion, an average daily oral dose of alkaloids up to 5 mg per 1 kg animal body weight proved to be safe.  相似文献   
7.
8.
To get access to the replication site, small non-enveloped DNA viruses have to cross the cell membrane using a limited number of capsid proteins, which also protect the viral genome in the extracellular environment. Most of DNA viruses have to reach the nucleus to replicate. The capsid proteins involved in transmembrane penetration are exposed or released during endosomal trafficking of the virus. Subsequently, the conserved domains of capsid proteins interact with cellular membranes and ensure their efficient permeabilization. This review summarizes our current knowledge concerning the role of capsid proteins of small non-enveloped DNA viruses in intracellular membrane perturbation in the early stages of infection.  相似文献   
9.
Objectives: It is the main goal of this study to investigate the relationships between physical abilities, cognitive abilities and the aspects of psychological well-being in people aged 80 or older. In contrast to other studies, we focus on the executive functions and mental rotation while investigating cognitive performance; this is because it is well known in the literature investigating younger participants that these functions relate to some kind of motor or physical activity.

Methods: 41 independently living persons over 80 years were enrolled. Physical activities (German Physical Activity Questionnaire 50+), balance (One leg stand), psychological well-being (Resilience, General depressions scale), cognitive abilities (Flanker task, Mental rotation, Number connection test) as well as the influence of gender and education status were analyzed.

Results: Higher physical activity correlates with higher resilience. Persons with higher education and men show better values on the depression scale. Better mental rotation ability could be detected in persons with higher education.

Discussion: This first experimental study with people only over 80 years demonstrates the importance of education and physical activity for different aspects of psychological well-being. Due to the aim of investigating participants only over 80 years living independently the sample size is small so the study should be further enlarged.  相似文献   
10.
5,10‐Methylenetetrahydrofolate reductase (MTHFR) deficiency is the most common inherited disorder of folate metabolism and causes severe hyperhomocysteinaemia. To better understand the relationship between mutation and function, we performed molecular genetic analysis of 76 MTHFR deficient patients, followed by extensive enzymatic characterization of fibroblasts from 72 of these. A deleterious mutation was detected on each of the 152 patient alleles, with one allele harboring two mutations. Sixty five different mutations (42 novel) were detected, including a common splicing mutation (c.1542G>A) found in 21 alleles. Using an enzyme assay in the physiological direction, we found residual activity (1.7%–42% of control) in 42 cell lines, of which 28 showed reduced affinity for nicotinamide adenine dinucleotide phosphate (NADPH), one reduced affinity for methylenetetrahydrofolate, five flavin adenine dinucleotide‐responsiveness, and 24 abnormal kinetics of S‐adenosylmethionine inhibition. Missense mutations causing virtually absent activity were found exclusively in the N‐terminal catalytic domain, whereas missense mutations in the C‐terminal regulatory domain caused decreased NADPH binding and disturbed inhibition by S‐adenosylmethionine. Characterization of patients in this way provides a basis for improved diagnosis using expanded enzymatic criteria, increases understanding of the molecular basis of MTHFR dysfunction, and points to the possible role of cofactor or substrate in the treatment of patients with specific mutations.  相似文献   
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