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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 frequency and complications of respiratory viral infections (RVI) were studied in 50 ambulatory lung transplant patients during a single winter season, using viral antigens, viral cultures and PCR of nasal washes or bronchoalveolar lavages. Patients' survival, episodes of acute rejection and occurrence of bronchiolitis obliterans (BO) or BO syndrome (BOS) were monitored for 1 yr after the study. Overall, 32 (64%) patients had 49 symptomatic episodes. Documented infections included eight due to respiratory syncytial virus (RSV), one due to parainfluenza virus (PIV) and 10 due to influenza (FLU). Four of the FLU infections were serological rises without symptoms. Overall, 17 (34%) patients had documented viral infection; four patients had lower respiratory involvement and two (one RSV, one PIV) were hospitalised for aerosolised ribavirin treatment. After 1 yr there were three (6%) deaths unrelated to RVI. BO or BOS had occurred in one (6%) out of 17 patients with and three (12%) out of 33 without RVI. Respiratory viruses infected one-third of ambulatory lung transplant recipients in a single season. In conclusion, respiratory viral infection was not associated with subsequent graft dysfunction. Larger prospective studies are required to better define the acute and long-term morbidity of these infections.  相似文献   
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4.
We used DNA-DNA hybridization to characterize a mycobacterial isolate, strain Linda, that was obtained from a patient with Crohn's disease and that has been reported to cause ileitis in experimental animals. We also investigated the association of this mycobacterium with Crohn's disease. Our results identified Mycobacterium strain Linda as a strain of Mycobacterium paratuberculosis, the etiologic agent of Johne's disease, a disease of ruminants that has some superficial resemblance to Crohn's disease. Sequences that hybridized with strain Linda DNA probes were detected in DNA extracted from human intestinal tissues from patients with Crohn's disease, ulcerative colitis, and noninflammatory bowel disease. These hybridizing DNA sequences were more prevalent in the muscle layers than in the intestinal mucosa, making it unlikely that they represented DNA from bacterial contaminants in the intestinal lumen. Measurement of the melting temperatures of the DNA-DNA hybrids formed between strain Linda probes and tissue DNAs indicated that the related sequences detected were of mycobacterial origin but were not identical to each other or to strain Linda DNA. These results do not support the proposed specific relationship between Mycobacterium strain Linda and Crohn's disease. The possible etiologic role of mycobacteria in Crohn's disease is discussed.  相似文献   
5.
Familial Polyposis and Carcinoma of the Colon   总被引:1,自引:0,他引:1  
Estes WL 《Annals of surgery》1948,127(5):1035-1045
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6.
Summary: Tumors and cortical dysplasia are associated with epilepsy, but few studies have examined the coexistence of neoplasia and dysplasia in these patients. We studied 13 patients (age 4–29 years) with recurrent seizures of 1 month to 21-year' duration (median 72 months). Ten patients were aged <21 years. Imaging studies localized the lesion to the temporal lobe (10 patients), parietal lobe (2 patients), and frontal lobe (1 patient). Tumors included ganglioglioma (8 patients), dysembryoplastic neuroepithelial tumor (DNT) (3 patients), and low-grade as- trocytoma (2 patients). Cortical dysplasia, including atypical aggregates of neurons (6 patients), multifocal loss of the cortical laminar architecture (7 patients), and neurons in the molecular layer of the cortex (3 patients) were observed near but separate from the tumor. Coexistence of certain tumors with cortical dysplasia, most frequently observed in the pediatric population, suggests a hamar-tomatous/dysplastic nature of the neoplasms.  相似文献   
7.
Research on medical care cost containment has indicated that the community-based service system is undergoing a process of restructuring within the context of an increasingly competitive environment and strong pressures to "medicalize" medical care services.  相似文献   
8.
The effects of methionine and ethionine on the fine structure of hepatic cell nucleoli of guinea pigs and rats were investigated. A single intraperitoneal injection of methionine into guinea pigs results in the disruption of nucleolonema as early as 2 hours after the injection. By 4 hours, nucleoli show complete fragmentation consisting of many small fragments and small remnants of nucleoli. Large aggregates of interchromatinic granules and condensation of chromatin appear in the nucleoplasm. These changes are remarkably similar to the lesions induced by ethionine in the liver of the rat or the guinea pig. The methionine-induced nuclear and nucleolar lesions persist up to 10 hours after the injection. The administration of adenine 4 hours after the methionine injection reverses the nucleolar lesions by 8 hours. The appearance of incompletely reconstructed nucleoli with twisted ropelike structures suggests a pattern of recovery very similar to the adenine-induced nucleolar reformation in ethionine-treated rats. Injecting methionine into rats induced no nucleolar abnormalities. It is suggested that the mechanism of nucleolar fragmentation induced by methionine or ethionine is related to the accumulation of S-adenosyl compounds with concomitant ATP deficiency in the liver.  相似文献   
9.
Using an oddball stimulus presentation paradigm, the effects of divided attention on auditory P300s were studied. Auditory attention was either divided or focused, depending on the demands placed on subjects during the performance of a concomitantly presented visual task. Two types of auditory tasks were performed under each of the two auditory attention conditions. In one, subjects responded to infrequently presented high pitched tones (oddball stimuli). In the other they responded to the occasional omission of a stimulus in an otherwise rhythmically presented chain of stimuli. P300s and reaction times were recorded to both the rare tones and the omissions. The Sternberg visual memory task was used to manipulate the subject's auditory attention state. Subjects actively performed the Sternberg task during the divided auditory attention condition, whereas during the focused attention condition they were not required to respond to the visual stimuli. During focused auditory attention, evoked auditory P300s were both larger and faster than their emitted counterparts. During divided attention, auditory P300s were reduced in amplitude but latency was unaffected. Evoked auditory P300s showed evidence of containing P300a as well as P300b components, particularly when attention was shared with the visual task.  相似文献   
10.
Simple diagnostic tests are needed for the detection of norovirus (NoV) outbreaks. Salivary antibody assays provide an attractive alternative to collecting and testing serum or stool samples. Antibodies to Norwalk virus (NV) in oral fluid samples were compared with NV antibodies in serum collected from 38 volunteers challenged with NV inoculum. Pre- and postchallenge (day 4, 8, 14, and 21) saliva and serum samples were examined by enzyme immunoassay (EIA) using recombinant NV antigen. Of 18 infected subjects (those who shed NV in stool or who demonstrated immunoglobulin G [IgG] seroconversion), 15 (83%) had > or =4-fold increases in NV-specific salivary IgA and 15 (83%) had > or =4-fold increases in NV-specific salivary IgG when prechallenge and postchallenge saliva samples were compared. When the results of the IgA and IgG assays were combined, all 18 infected subjects showed > or =4-fold increases in NV-specific salivary IgG or IgA postchallenge titers compared to their prechallenge titers. One of 19 uninfected subjects had a > or =4-fold increase in NV-specific salivary IgG. The sensitivity of the combined assay results was 100%, and the specificity was 95%. NV-specific salivary IgA titers peaked around 14 days postchallenge. NV-specific salivary IgG and serum IgG titers continued to rise through 21 days postchallenge. The application of this EIA to an elementary school outbreak indicated that 67% of the subjects with confirmed infections had >4-fold rises in anti-NoV IgA when an antigen in the same genetic cluster as the outbreak virus was used. This is the first documented mucosal antibody response to NoV in children. This EIA provides a useful approach for diagnosing NoV outbreaks.  相似文献   
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