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891.
Cavernous hemangiomas are vascular malformations of the central nervous system that may rarely affect the epidural space of the spine. We report a case of an epidural cavernous hemangioma which was originating from the left C8 nerve root and extending anteriorly to the apex of the left lung.  相似文献   
892.
Here we report a case of mediastinitis due to Mycobacterium fortuitum infection in a child after a Fontan operation. To our knowledge this is the first report of atypical mycobacterial mediastinal infection after congenital heart surgery. Atypical mycobacteria can be the cause of "culture negative" sternal and thoracotomy wound infections. A brief review of the literature is included in the discussion.  相似文献   
893.
Two distinct pathogenic mechanisms, adhesion to polymer surfaces and subsequent accumulation of sessile bacterial cells, are considered important pathogenic steps in foreign body infections caused by Staphylococcus epidermidis. By using mitomycin mutagenesis, we have recently generated a mutant, strain M7, from S. epidermidis RP62A which is unaffected in adhesion but deficient in accumulation on glass or polystyrene surfaces and lacks a 115-kDa extracellular protein (designated the 140-kDa antigen; F. Schumacher-Perdreau, C. Heilmann, G. Peters, F. G?tz, and G. Pulverer, FEMS Microbiol. Lett. 117:71-78, 1994). To evaluate the role of this protein in accumulation, we harvested extracellular proteins from S. epidermidis RP62A grown on dialysis membranes placed over chemically defined medium, purified the protein by using ion-exchange chromatography, determined its N-terminal amino acid sequence, and raised antiserum in rabbits. The antibody recognized only a single band in a Western immunoblot of the crude extracellular extract. With the microtiter biofilm test, antiserum at a dilution of < or =1:1,000 blocked accumulation of RP62A up to 98% whereas preimmune serum did not. The 140-kDa antigen was found only in extracellular products from bacteria grown under sessile conditions. Of 58 coagulase-negative clinical isolates, 32 strains were 140-kDa antigen positive and produced significantly larger amounts of biofilm than the 26 strains that were 140-kDa antigen negative. The 140-kDa protein appears to be biochemically and functionally unrelated to any previously described factors associated with biofilm formation. Thus, the 140-kDa antigen, referred to as accumulation-associated protein, may be a factor essential in S. epidermidis accumulation and, due to its immunogenicity, may allow the development of novel immunotherapeutic strategies for prevention of foreign body infection.  相似文献   
894.
Several studies have demonstrated protein-protein interactions between microsomal triglyceride transfer protein (MTP) and apolipoprotein B (apoB). However, the binding sites involved in these interactions have not been elucidated. To identify an MTP binding site in apoB, we have expressed several apoB sequences as fusion proteins with the eight-amino acid FLAG peptide. The chimeras were transiently expressed in COS cells, and conditioned media were used to study the binding of these sequences to either immobilized or soluble MTP. A polypeptide containing amino acids 270-570 (B:270-570), but not 1-300, bound to MTP. AGI-S17, an antagonist of apoB-MTP binding, inhibited the binding of B:270-570 to MTP but not to M2, a monoclonal antibody that recognizes the FLAG peptide. These data indicated that B:270-570 contains an MTP binding site. Next, sequences within 270-570 were subjected to C-terminal truncations at natural proline residues. B:270-509 bound less efficiently than B:270-570, whereas, B:270-430 and other shorter chimeras did not bind to MTP. Furthermore, truncations at amino acids 502 and 509 decreased MTP binding by 73 and 42%, respectively. These data indicate that B:430-570 in the alpha1-globular domain of apoB plays a crucial role in MTP binding and presumably in the initiation and maturation of apoB-containing lipoproteins.  相似文献   
895.
We present an unusual combination of vascular complications of cavernous sinus thrombosis in a 7-year-old girl. MRI and MR angiography showed occlusion of the intracranial portion of the left internal carotid artery and a contralateral giant cavernous carotid aneurysm. This combination of vascular findings may influence the management in such cases.  相似文献   
896.
This paper describes the development and implementation of a self-tuning microcontroller-based instrument for measuring different thicknesses of glass and glass substitutes. The instrument’s hardware was successfully tested in the laboratory on coated and uncoated glass under a variety of conditions. It is designed to provide high performance and high precision measuring capability to the system user. The obtained experimental data suggest that the proposed instrument surpasses existing techniques in its accuracy, reliability, simple operation, safety and measuring capability.  相似文献   
897.
Multimedia Tools and Applications - GAN-based image colorization techniques are capable of producing highly realistic color in real-time. Subjective assessment of these approaches has demonstrated...  相似文献   
898.
Learning in the multiple class random neural network   总被引:3,自引:0,他引:3  
Spiked recurrent neural networks with "multiple classes" of signals have been recently introduced by Gelenbe and Fourneau (1999), as an extension of the recurrent spiked random neural network introduced by Gelenbe (1989). These new networks can represent interconnected neurons, which simultaneously process multiple streams of data such as the color information of images, or networks which simultaneously process streams of data from multiple sensors. This paper introduces a learning algorithm which applies both to recurrent and feedforward multiple signal class random neural networks (MCRNNs). It is based on gradient descent optimization of a cost function. The algorithm exploits the analytical properties of the MCRNN and requires the solution of a system of nC linear and nC nonlinear equations (where C is the number of signal classes and n is the number of neurons) each time the network learns a new input-output pair. Thus, the algorithm is of O([nC]/sup 3/) complexity for the recurrent case, and O([nC]/sup 2/) for a feedforward MCRNN. Finally, we apply this learning algorithm to color texture modeling (learning), based on learning the weights of a recurrent network directly from the color texture image. The same trained recurrent network is then used to generate a synthetic texture that imitates the original. This approach is illustrated with various synthetic and natural textures.  相似文献   
899.
We examined the genomic status of cyclin-dependent kinase-4 and -6 inhibitors, p16INK4,p15INK4B, and p18, in 40 primary lung cancers and 31 metastatic lung cancers. Alterations of the p16INK4 gene were detected in 6 (2 insertions and 4 homozygous deletions) of 22 metastatic non-small cell lung cancers (NSCLCs; 27%), but none were detected in 25 primary NSCLCs, 15 primary small cell lung cancers (SCLCs), or 9 metastatic SCLCs, indicating that mutation in the p16INK4 gene is a late event in NSCLC carcinogenesis. Although three intragenic mutations of the p15INK4B gene were detected in 25 primary NSCLCs (12%) and five homozygous deletions of the p15INK4B gene were detected in 22 NSCLCs (23%), no genetic alterations of the p15INK4B gene were found in primary and metastatic SCLCs. The p18 gene was wild type in these 71 lung cancers, except 1 metastatic NSCLC which showed loss of heterozygosity. We also examined alterations of these three genes and expression of p16INK4 in 21 human lung cancer cell lines. Alterations of the p16INK4 and p15INK4B genes were detected in 71% of the NSCLC cell lines (n = 14) and 50% of the NSCLC cell lines (n = 14), respectively, but there were none in the 7 SCLC cell lines studied. No p18 mutations were detected in these 21 cell lines. These results indicate that both p16INK4 and p15INK4B gene mutations are associated with tumor progression of a subset of NSCLC, but not of SCLC, and that p15INK4B mutations might also be an early event in the molecular pathogenesis of a subset of NSCLC.  相似文献   
900.
A REVIEW OF HYDROCARBON HABITATS IN BANGLADESH   总被引:1,自引:0,他引:1  
Bangladesh, with approximately 25 trillion cubic feet (TCF) of gas initially in place and 15.52 TCF of initial recoverable reserves, and an average success ratio of 3:1, has emerged as a new hydrocarbon exploration frontier. The country occupies the major part of the Bengal Basin and is essentially located in a convergent-margin basin that owes its origin to the Early Cretaceous rifting of the Indian Plate away from Antarctica, the formation of the Indian Ocean (part of Palaeo-Tethys), and ultimately the collision of the Indian Plate with the Eurasian Plate. The Bengal Basin is filled with approximately 20km of mostly Tertiary siliciclastic sediments comprising a spectrum of facies including deep- to shallow-marine, deltaic and fluvial types. The presence of thick sequences of reservoir-quality sandstones coupled with organic-rich shales, and of different kinds of traps including broad anticlinal structures, makes the basin highly prospective for hydrocarbon exploration. Of the exploration wells (52 onshore; 12 offshore) so far drilled in Bangladesh, a total of 22 reported commercial discoveries of natural gas from sandstones in the Miocene-Pliocene Surma Group. The hydrocarbon potential of older sequences, especially the Eocene Sylhet Limestone and the Oligocene Barail Group, are not adequately known at present. However, initial indications (e.g. the presence of suitable source rocks, high-pressure zones, "dim" and "flat" spots and velocity sag in reef complexes in the Sylhet Limestone) tend to favour the hydrocarbon prospectivity of these sequences.  相似文献   
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