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991.
992.
The paper describes a new method for visualization and analysis of multivariate laser range data using complex valued non orthogonal Gabor wavelets (D. Gabor, 1946), principal component analysis and a topological mapping network. The initial data set that provides both shape and texture information is encoded in terms of both amplitude and phase of a complex valued 2D image function. A set of carefully designed oriented Gabor filters performs a decomposition of the data and allows for retrieving local shape and texture features. The feature vector obtained from this method is multidimensional and in order to evaluate similar data features, further subspace methods to transform the data onto visualizable attributes, such as R, G, B, have to be determined. For this purpose, a feature based visualization pipeline is proposed consisting of principal component analysis, normalization and a topological mapping network. This process finally renders a R,G,B subspace representation of the multidimensional feature vector. Our method is primarily applied to the visual analysis of features in human faces but is not restricted to that  相似文献   
993.
There have been numerous reports as well as case presentations, in the field of clinical research since Fukuyama type congenital muscular dystrophy (FCMD) was first reported by Fukuyama et al. as a peculiar form of congenital progressive muscular dystrophy (CMD). Toda et al. localized the FCMD gene locus to chromosome 9q31-33 using genetic linkage analysis. Clinical application of molecular genetic studies is a new and exciting aspect of FCMD research. The author reviewed the literature and discusses herein: [1] the classification of CMD and the position of FCMD, [2] researches on the pathogenesis and pathophysiology of FCMD, [3] DNA diagnosis using polymorphism analysis (carrier diagnosis and prenatal diagnosis), [4] approaches to clinical heterogeneity in FCMD, [5] the difference between FCMD and Walker-Warburg syndrome. In addition, data accumulated by the authors are presented.  相似文献   
994.
The Heidelberg Retina Tomograph is a confocal scanning laser ophthalmoscope which obtains three-dimensional images of the optic nerve head and the retina in the human eye. Because of its potential investigative uses in experimental animal models of glaucoma, we examined its variability with optic nerve head measurements in the rabbit eye. Three topographic images, recorded on different days, were acquired from the right eye of 5 New Zealand white rabbits over 3 weeks. To estimate the lowest possible variability, a second series of three images was recorded in a single setting without displacement of the rabbits. The average coefficient of variability (standard deviation/mean) for the estimate of the optic nerve head cup volume (volume below surface) was 11.1% in the independent series and was decreased to 3.0% in the sequentially recorded series without displacement of the rabbits (P < 0.001). These values indicate a comparable variability for the estimate of the optic nerve head cup volume in the rabbit compared with those reported for the human eye. This variability is considerably decreased by maximally standardizing the image acquisition position, suggesting that variability largely depends on the alignment between the subject and the laser-scanner.  相似文献   
995.
The rate of GABA turnover was determined in nine microdissected brain regions in adult male and female rats. In the medial preoptic nucleus (central aspect) and ventromedial nucleus (ventrolateral aspect) of the hypothalamus, areas involved in the regulation of gonadotropin secretion and sex behavior, GABAergic neuronal activity was about 2-fold greater in males than females. These results demonstrate a striking sexual dimorphism in the activity of specific populations of hypothalamic GABAergic neurons.  相似文献   
996.
The concentrations of cefuroxime in human alveolar macrophages (AM), epithelial lining fluid (ELF), bronchial mucosal biopsies and serum were measured after a single dose, equivalent to 500 mg of cefuroxime base, given in the form of the orally-administered pro-drug, cefuroxime axetil. Fourteen patients undergoing fibreoptic bronchoscopy with bronchoalveolar lavage were studied. The mean ELF concentration was 0.7 mg/L, that of bronchial biopsies was 1.8 mg/kg and that of serum 3.5 mg/L. AM-associated cefuroxime was detected in nine patients. To assess the in-vitro activity of the concentrations achieved at the potential sites of infection, clinical isolates of common respiratory pathogens were exposed to two concentrations of cefuroxime, based on the observed concentrations in ELF and bronchial mucosa. ELF and mucosal site concentrations were effective against Streptococcus pneumoniae (except one strain with reduced susceptibility to benzyl penicillin) and Haemophilus influenzae. The ELF concentration was less effective against Moraxella catarrhalis.  相似文献   
997.
BACKGROUND/AIMS: Differentiating between an acute hepatitis B (AH-B) infection and an acute exacerbation of a chronic hepatitis B (CH-B) infection can present a problem for the clinician. The only current serological method of distinguishing between acute and symptomatic chronic hepatitis B virus (HBV) infection is the immunoglobulin M antibody to hepatitis B core antigen (anti-HBc) assay, which can be problematic. Therefore, in an attempt to better distinguish between acute and chronic HBV infection, sera from 26 patients with AH-B and 53 patients with CH-B were compared in a variety of experimental immunoassays. METHODS: Experimental assays have been designed to detect free antibody to hepatitis B e antigen (anti-HBe), hepatitis B e antigen (HBeAg)/anti-HBe immune complexes (ICs), and hepatitis B surface antigens (HBsAg)/antibody to hepatitis B surface antigen (anti-HBs) in the presence of excess antigen. An additional assay was developed to detect a novel anti-HBc specificity, designated antibody to woodchuck hepatitis virus (anti-HBcW), which cross-reacts with the core antigen of the woodchuck hepatitis virus. RESULTS: Sera from patients with CH-B showed significantly higher levels of free anti-HBe, HBeAg/anti-HBe ICs, and HBsAg/anti-HBs ICs compared with AH-B patient sera. Furthermore, patients with CH-B consistently produced high titer anti-HBcW, whereas patients with AH-B produced little or no anti-HBcW antibody. CONCLUSIONS: The serology of AH-B infection and symptomatic CH-B infection can be distinguished using a variety of experimental immunoassays in addition to the immunoglobulin M anti-HBc assay.  相似文献   
998.
From January 1960 to June 1995, 185 patients underwent reoperation without esophageal resection for symptoms of recurrent gastroesophageal reflux disease. There were 102 men and 83 women. Median age was 58 years (range 20 to 84 years). A single previous antireflux operation had been performed in 147 patients, two in 33, and three in 5. The median interval between the reoperation and the previous operation was 36 months (range 1 to 291 months). Indications for reoperation were symptoms in 184 patients and a large paraesophageal hernia in one patients. The surgical approach was by means of a thoracotomy in 133 patients (71.9%), laparotomy in 27 (14.6%), and a thoracoabdominal incision in 25 (13.5%). A Nissen fundoplication was performed in 107 patients (57.8%), Belsey fundoplication in 47 (25.4%), truncal vagotomy and antrectomy with Roux-en-Y reconstruction in 17 (9.2%), anatomic hernia repair in 12 (6.5%), and Hill gastropexy in 2 (1.1%). A Collis gastroplasty was added to the fundoplication in 116 patients (62.7%), and a pyloroplasty was performed in 17 (9.2%). There was one operative death (0.5%). Complications occurred in 47 patients (25.4%). Median postoperative hospitalization was 9 days (range 5 to 58 days). Follow-up was complete in 156 patients (84.3%) and ranged from 3 to 283 months (median 44 months). Improvement occurred in 137 patients (87.8%). Functional results were classified as excellent in 65 patients (41.6%), good in 29 (18.6%), fair in 43 (27.6%), and poor in 19 (12.2%). No single operative approach or procedure proved to be functionally superior. We conclude that reoperation with esophageal preservation after a failed antireflux procedure will result in significant functional benefit and can be performed with low mortality and acceptable morbidity. The type of repair should be tailored to the individual patient.  相似文献   
999.
1000.
Human monocyte-derived macrophages (MDM) provided this laboratory with a tool to develop a primary-cell assay for evaluating the relative virulence of newly constructed Salmonella typhi carrier strains. In this study, the interaction with and survival within MDM were compared for delta aroA143-attenuated strains, wild-type virulent strains, and the current oral-vaccine strain, Ty21a.  相似文献   
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