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Staphylococcus epidermidis is frequently resistant to first-generation cephalosporins. Although I have generally changed the therapy of S. epidermidis CAPD peritonitis to vancomycin when laboratory reports indicate cephalosporin resistance, it frequently appeared that improvement from the cephalosporin was taking place at the time of antibiotic conversion. Should the antibiotics be changed in this setting?  相似文献   
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A 26-year-old female was on continuous ambulatory peritoneal dialysis (CAPD) because of diabetic end-stage renal failure. She developed an acute peritonitis that relapsed repeatedly despite appropriate antibiotic treatment. Investigations showed the presence of a splenic abscess, and splenectomy and peritoneal cannula removal were required. The patient died of myocardial infarction two weeks postoperatively. This is the first recorded case of peritonitis secondary to splenic abscess in a CAPD patient. Autopsy findings suggest that the abscess developed from infection of a splenic infarct.  相似文献   
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Knowledge of the response of the primary visual cortex to the various spatial frequencies and orientations in the visual scene should help us understand the principles by which the brain recognizes patterns. Current information about the cortical layout of spatial frequency response is still incomplete because of difficulties in recording and interpreting adequate data. Here, we report results from a study of the cat primary visual cortex in which we employed a new image-analysis method that allows improved separation of signal from noise and that we used to examine the neurooptical response of the primary visual cortex to drifting sine gratings over a range of orientations and spatial frequencies. We found that (i) the optical responses to all orientations and spatial frequencies were well approximated by weighted sums of only two pairs of basis pictures, one pair for orientation and a different pair for spatial frequency; (ii) the weightings of the two pictures in each pair were approximately in quadrature (1/4 cycle apart); and (iii) our spatial frequency data revealed a cortical map that continuously assigns different optimal spatial frequency responses to different cortical locations over the entire spatial frequency range.  相似文献   
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cDNA clones of potato virus X (PVXcp strain), potato virus Y (PVYo strain), potato leaf roll virus (PLRV) and potato spindle tuber viroid (PSTV) were used separately or combined for the detection of the corresponding RNAs in extracts of infected plants. A general method for the rapid preparation of RNA extracts without use of organic solvents (i.e. phenol) was developed for this purpose. Plant extracts from a range of field, artificially inoculated germplasm genotypes, micro-propagated and protoplast samples, as well as vector insect extracts, were dot-blotted onto nylon or nitrocellulose membranes, subjected to sandwich nucleic acid hybridization with non-labelled specific single-stranded DNA probes followed by a biotin-labelled second step hybridization probe. Each probe was virus-specific but not strain-specific. Healthy or non-related plant extracts developed very faint or no signals. Sensitivity was tested by slot-blot hybridization. Detection levels were between 1.5 to 6 pg of viral nucleic acids and between 20 to 50 times more sensitive than standard double antibody sandwich enzyme-linked immunosorbent assay (DAS-ELISA). The assay developed was tested with material that was prepared for processing in the field (combination of fresh sap with extraction solution) and tested under simple laboratory conditions for detection. It was also successfully employed for screening of germplasm for virus resistance, detection of pathogens in vector insects, plantlets grown in vitro and in more sophisticated quantitative determinations of viral replication in artificially inoculated plants and protoplasts.  相似文献   
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Ohne ZusammenfassungSchliesslich fühlen wir uns verpflichtet, Herrn Dr. Emanuel Liebermann für die gefällige Verfertigung der beigegebenen Zeichnung aufrichtigen Dank zu sagen.  相似文献   
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Ciliary dysfunction in primary ciliary dyskinesia (PCD) may be associated with bronchiolitis. Diffuse bronchiolitis has been reported in a subset of PCD patients who have Kartagener''s syndrome in Japan. We report a case of follicular bronchiolitis (FB) in a case of PCD presenting with recurrent episodes of cough, dyspnea, and bronchiectasis. This may motivate researchers to study rarer variants and presentations in PCD.  相似文献   
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