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61.
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Ocular trauma is not uncommon. Because the tissues associated with visual function are delicate and remarkably specialized, care of ocular injuries is best left to well-trained specialists. Initial care, however, is often simply common sense. Irrigation of chemical burns, sterile techniques, and procedures that salvage tissue are good general principles.  相似文献   
63.
The association of sociodemographic and family composition data with obesity was studied in 1213 black and 1166 white girls, ages 9 and 10, enrolled in the National Heart, Lung, and Blood Institute''s Growth and Health Study. Obesity was defined as body mass index at or greater than age- and sex-specific 85th percentile as outlined in the Second National Health and Nutrition Examination Survey. The prevalence of obesity was higher for pubertal girls than for prepubertal girls and for girls with older mothers/female guardians. As odds ratio of 1.14 was observed for each 5-year increase in maternal age. Obesity was less common for girls with more siblings; the odds for obesity decreased by 14% for each additional sibling in the household. In blacks, the prevalence of obesity was not related to parental employment or to parental education. In whites, the odds of obesity were higher for girls with no employed parent/guardian in the household and for girls with parents or guardians with lower levels of educational attainment. Examining the associations between sociodemographic factors and risk of childhood obesity provides important clues for understanding racial differences in obesity, a major risk factor for coronary heart disease.  相似文献   
64.
Malignant melanoma associated with melanocytoma of the optic disc   总被引:1,自引:0,他引:1  
A 61-year-old white man underwent enucleation because of progressive growth of a pigmented epipapillary tumor that was diagnosed 9 years earlier as an optic nerve and juxtapapillary melanocytoma. Histopathologic studies showed the tumor was a malignant melanoma of the optic disc and juxtapapillary retina and choroid. Foci of typical melanocytoma cells were within the tumor. The tumor produced segmental atrophy of the optic nerve. This is a rare example of a malignant melanoma developing in conjunction with a lesion that possessed typical clinical and histopathologic features of a melanocytoma of the optic disc.  相似文献   
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S H Stern 《Primary care》1988,15(4):809-826
An approach that allows a consistent, thorough evaluation can be recommended by a mnemonic using the words ankle/foot. The maxim about foot and ankle pain is that "the good exam begins at the back and ends at the toe." During this exam, the cutaneous, vascular, and neural systems need careful evaluation. The exam is directed to the region of maximal discomfort where careful palpation should pinpoint the spot of greatest tenderness. Once this region has been localized and signs and symptoms collected, consider the differential diagnosis specific for that area. This will narrow the focus, make the number of potential pain sources manageable, and often provide the answer. When the diagnosis is still unclear, obtain standard x-rays of the area. A directed evaluation to probe the region is appropriate. This can mean a bone scan to detect early avascular necrosis, stress fractures or osteomyelitis; an EMG-NCS to assess the neural circuitry; and special x-ray views, CAT scan, NMR, or arthrogram to uncover the difficult fracture. At this point, fortunately, the primary physician is not alone. The diagnostic dilemma or the difficult management case can be referred for a second opinion or therapeutic assistance to a podiatrist, rheumatologist, or the orthopedist with a special interest in feet.  相似文献   
67.
The performance of twenty children (3-11 years of age) in a complex operant test battery (OTB) was evaluated. The operant schedules, or tasks, used in the OTB were identical to those originally designed and currently used to assess complex brain function in nonhuman primate laboratory animals (monkeys). The OTB consisted of five operant tasks: 1) Progressive-Ratio [PR]; 2) Conditioned-Position Responding [CPR]; 3) Temporal Response Differentiation [TRD]; 4) Delayed Matching-to-Sample [DMTS] and 5) Incremental Repeated Acquisition [IRA]. These operant tasks are thought to engender responding indicative of processes associated with: 1) motivation; 2) color and position discrimination; 3) time-perception; 4) short-term memory and attention; and 5) learning, respectively. The parameters for each of the tasks in the OTB were optimized for use in the clinical setting to assess cognitive function in children. In the small population studied, performance in the IRA, DMB and TRD tasks was age related. Of the four 6-yr-olds studied, only those categorized as having either learning disabilities (LD, n = 1) or attention deficit disorders (ADD, n = 2) did not complete the "learning" task. By comparison of human and monkey performance in the OTB, we also hope to validate the use of laboratory animal models in research efforts designed to yield insight into complex human brain function. It is also hoped that assessment of children's performance in the tasks in the OTB will assist in the diagnosis and treatment of certain childhood disorders such as learning disabilities and/or attention deficit disorders.  相似文献   
68.
Low-artifact intravascular devices: MR imaging evaluation   总被引:2,自引:0,他引:2  
Flow-phantom magnetic resonance (MR) imaging, with use of both spin-echo (SE) and gradient-echo (GRE) techniques at 1.5 T, was performed on the percutaneous Greenfield (beta-III titanium alloy [TMA wire]), Amplatz (MP32-N alloy), and Simon nitinol filters and TMA wire facsimiles of the bird's nest, Gunther, new retrievable, and Amplatz vena caval filters. SE imaging allowed detection of thrombi as small as 5 X 5 mm trapped within the percutaneous Greenfield, Simon nitinol, and TMA-wire facsimile filters; with the MP32-N Amplatz filter, a larger volume of thrombus (10 X 20-mm clots) was necessary for clot detection. GRE imaging allowed detection of intraluminal tilting of the percutaneous Greenfield and facsimile Amplatz (TMA-wire) filters. GRE imaging was useful for demonstrating postfilter turbulence due to clots, which was greatest for the Amplatz filter. Imaging of facsimile vascular devices made of tantalum or TMA wire did not cause the severe "black-hole" MR artifacts typical of the stainless-steel devices. SE and GRE imaging were very useful for determining caval patency in two patients with previously placed Mobin-Uddin filters. Noninvasive MR evaluation of blood vessels in the presence of a variety of low-artifact intravascular devices appears feasible.  相似文献   
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70.
Advanced glycation end products (AGEs), the final products of nonenzymatic glycation and oxidation of proteins, are found in the plasma and accumulate in the tissues during aging and at an accelerated rate in diabetes. A novel integral membrane protein, termed receptor for AGE (RAGE), forms a central part of the cell surface binding site for AGEs. Using monospecific, polyclonal antibody raised to human recombinant and bovine RAGE, immunostaining of bovine tissues showed RAGE in the vasculature, endothelium, and smooth muscle cells and in mononuclear cells in the tissues. Consistent with these data, RAGE antigen and mRNA were identified in cultured bovine endothelium, vascular smooth muscle, and monocyte-derived macrophages. RAGE antigen was also visualized in bovine cardiac myocytes as well as in cultures of neonatal rat cardiac myocytes and in neural tissue where motor neurons, peripheral nerves, and a population of cortical neurons were positive. In situ hybridization confirmed the presence of RAGE mRNA in the tissues, and studies with rat PC12 pheochromocytes indicated that they provide a neuronal-related cell culture model for examining RAGE expression. Pathological studies of human atherosclerotic plaques showed infiltration of RAGE-expressing cells in the expanded intima. These results indicate that RAGE is present in multiple tissues and suggest the potential relevance of AGE-RAGE interactions for modulating properties of the vasculature as well as neural and cardiac function, prominent areas of involvement in diabetes and in the normal aging process.  相似文献   
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