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51.
We report the imaging findings in five patients with a unique dysmyelinating disorder. MR studies of these infants showed obstructive hydrocephalus caused by mass effect produced by an enlarged cerebellum. The white matter of an enlarged cerebrum and cerebellum showed delayed myelination. Proton spectroscopy showed normal N-acetylaspartate (NAA) levels. While the dysmyelinating disorder was clearly differentiated from Canavan disease by an absence of elevated NAA and differing histopathologic findings and autosomal-dominant inheritance pattern, there were similarities to this disease in the presentation and, to some extent, in the initial imaging findings.  相似文献   
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Airway control is the initial priority in the management of the injured patient. The purpose of this investigation was to evaluate the experience of an aeromedical transport team in the utilization of rapid sequence induction (RSI) for endotracheal intubation in the prehospital setting. Records of a consecutive series of injured patients undergoing RSI between June 1988 and July 1992 by a university-based aeromedical transport team were reviewed for demographics, intubation mishaps, and pulmonary complications. The relationship between intubation mishaps and pulmonary complications was analyzed. Eighty-four patients were studied with a mean age of 30.8 +/- 15.3 years. The mean Revised Trauma Score was 11.3 +/- 2.4, and the mean Injury Severity Score (ISS) was 19.6 +/- 11.5. Intubation mishaps occurred in 15 patients (18%), and pulmonary complications developed in 22 (29%) of the 75 patients surviving longer than 24 hours. There was no relationship between intubation mishaps and pulmonary complications. Abbreviated Injury Scale (AIS) face score was significantly higher in patients with intubation mishaps, compared with patients without mishaps (1.1 +/- 1.2 and 0.5 +/- 0.9, respectively, P < .05, Wilcoxon rank-sum). ISS and AIS chest were higher in patients with pulmonary complications, compared with those without (25.7 +/- 12.6 and 17.4 +/- 10.3 and 2.2 +/- 1.8 and 1.0 +/- 1.5, ISS and AIS respectively; P < .05, Wilcoxon rank-sum). Eighty-one patients (96%) underwent successful RSI, 73 (87%) on the first attempt. Failure to intubate occurred in three patients (4%). Performed under strict protocol by appropriately trained aeromedical transport personnel, RSI is an effective means to facilitate endotracheal intubation in the injured patient requiring definitive airway control. Pulmonary complications were related to injury severity and not to intubation mishaps.  相似文献   
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Normal or increased amounts of series III porphyrins with greater amounts of series I were observed on incubation of PBG in hemolysates of congenital erythropoietic porphyria vs. normal erythrocytes, human or bovine. Correlation with reticulocyte percentage was poor, in the aggregate a general trend toward increased values of both isomers I and III was noted with increasing reticulocytes. When the percent of type III was low the net amount was increased as compared with normal. Hemolysates of non-porphyric, reticulocyte-rich red cells (hemolytic or posthemorrhagic anemia) formed only minute amounts of type I porphyrin but at the same time no more, or even less type III than the porphyric hemolysates, although representing red cells of greater reticulocyte content. No evidence of deficient heme synthesis was observed in porphyric hemolysates incubayed with [14C]-porphobilinogen or 59Fe. Other studies of porphyric hemolysates incubated with and without added mouse spleen synthetase failed to reveal evidence of an absolute UPG-III cosynthetase (Co-S) deficiency. The large increases of type I porphyrin with normal or increased formation of type III, both in the disease and in the hemolysates, are believed due to a primary increase of ALA-S or UPG-S activity rather than a decrease of Co-S. Possible mutations which might be responsible for this increase are considered.  相似文献   
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Spectral morphometric characterization of typical chronic lymphocytic leukemia (B-CLL) cells vs normal small lymphocytes stained by May-Grunwald-Giemsa was carried out by multipixel spectral imaging. The light intensity (450-850 nm of 10(4) pixels) from nuclear domains of each stained cell was recorded and represented as light transmittance spectra and optical density. Transmitted light spectra of two nuclear domains were determined, one with low-intensity light transmittance (LIT) and the other with high-intensity light transmittance (HIT). A spectral library was constructed using the four transmitted light spectra representing the HIT and LIT domains of the normal human lymphocytes and the LIT and HIT domains of the CLL cells. The spectral library served to scan CLL lymphocytes from 10 cases of CLL and the lymphocytes of 10 healthy individuals. Each spectrally similar domain in the nuclei of the lymphocytes was assigned an arbitrary color. The morphometric analysis of the spectrally classified nuclei showed specific spectral patterns for B-CLL in 92% of the cells. The specific spectral characteristics of each of the two cell populations were also observed by their optical density light absorbance spectra. We propose that spectral morphometric analysis may serve as an additional diagnostic tool for detection of CLL lymphocytes in a hematological specimen.  相似文献   
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Chiral separations employing molecular imprint polymer (MIP) stationary phases in both open tubular liquid chromatography (OT-LC) and capillary electrochromatography (OT-CEC) are demonstrated. MIPs are highly crosslinked polymers containing spatial and functionality memory of template molecules which provide a higher degree of selectivity when used as stationary phases for chromatographic separations. Thin films of molecular imprinted polymers bonded to the inner walls of 25 microm ID fused-silica capillaries were prepared using an in situ polymerization technique developed in our laboratory that allows the use of conventional fused-silica capillaries with polyimide outer coatings. The success rate in preparing such open tubular columns was about 70%. Methacrylic acid and 2-vinyl pyridine were chosen as functional monomers, and either ethylene dimethacrylate or trimethylol propane trimethacrylate was used as the crosslinker. Toluene was employed as the porogen. Effects of polymerization conditions on column preparation and chromatographic performance were studied. Enantiomeric separations of D- and L-dansyl phenylalanines were achieved in both OT-LC and OT-CEC modes with good selectivity and efficiencies. Both types of separations may be performed on the same column using a single commercial instrument.  相似文献   
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The F-type ATPase, TF0F1, from the thermophilic Bacillus PS3, which is free of nucleotides after isolation, was specifically loaded with one 2-azido ADP on a non-catalytic site. The enzyme was covalently modified to various extents and the rate of ATP synthesis and ATP hydrolysis was measured. Both ATP synthesis and ATP hydrolysis extrapolated to zero for covalently binding one nucleotide per enzyme. This was interpreted such that the non-catalytic sites are involved in the coupled catalytic process.  相似文献   
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