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161.
A clinical investigation was carried out in 39 patients with atypical mycobacteriosis (AM). The patients at our hospital diagnosed as having AM during an 11-year period from 1981 to 1991 were reviewed in this study. The incidence of AM among all of mycobacterial infections has been increasing since 1988. The atypical mycobacteria detected included M. avium complex (MAC) in 79%, M. kansasii in 26%, and other organisms in 5%. Patients who had primary infection without underlying respiratory disease were compared with those who had secondary infection. In secondary infection, MAC was detected in the sputum of a high percentage of patients and was positive for more than 6 months despite therapy. Gamma globulin levels were also increased in patients with secondary infection. Cell mediated immunity was examined by the DNCB reaction and the detection of CD4- and CD8- positive T lymphocytes. The DNCB skin reaction was positive in 6 out of 26 patients with secondary infection. The percentage of CD8- positive T lymphocytes was higher in patients with secondary disease. Fischer's ratio (indicating the balance of plasma amino acids) was also examined as an index of the nutritional status. It was significantly lower in secondary infection compared with primary infection. Moreover, secondary infection was associated with a lower positive rate for the DNCB skin reaction and a lower Fischer's ratio when compared with pulmonary tuberculosis. Thus impairment of cell-mediated immunity, malnutrition, and a poor prognosis were significantly more common in secondary infection compared with primary infection.  相似文献   
162.
A study was undertaken to determine if a relatively minor modification of our existing specimen collection tubes could enhance the long-term stability of blood cocaine. We added cocaine, benzoylecgonine (BE) and ethanol to whole sheep blood in glass tubes that were prepared to contain one of several combinations of preservatives and anticoagulant. On day 1 and at intervals of up to one year, the drugs were measured by gas chromatography-mass spectrometry (cocaine and BE) or headspace gas chromatography (ethanol). Storage of blood containing 200 ng/mL cocaine at 4 degrees C for one year resulted in 100% loss of the drug using our normal 10 mL specimen collection tubes containing 100 mg sodium fluoride and 20 mg potassium oxalate. The substitution of oxalic acid for potassium oxalate reduced this loss to 76% without any significant effect on the benzoylecgonine or ethanol concentrations. Further addition of 10 mg echothiophate iodide, a quaternary ammonium compound, brought the cocaine loss down to 60% of the original concentration by one year. Further work will be required to determine if oxalic acid and/or echothiophate iodide could be used in blood collection vials intended for forensic toxicological purposes without any detrimental effect on other assays.  相似文献   
163.
Using a gas-atomized Ni59.35Nb34.45Sn6.2 metallic glassy alloy powder blended with Sn powder of various contents, Ni-Nb-Sn bulk metallic glassy matrix composites were fabricated by a microwave (MW)–induced sintering process in a single-mode 2.45 GHz MW applicator in a separated magnetic field. The Ni59.35Nb34.45Sn6.2 glassy alloy powder and its mixed powders containing Sn particles could be heated well in the magnetic field. The addition of Sn particles promoted densification of the sintered Ni59.35Nb34.45Sn6.2 metallic glassy powder. Bulk samples without crystallization of the glassy matrix and with good bonding state among the particles were achieved at a sintering temperature of 833 K.  相似文献   
164.
Ambiguous abdominal situs, asplenia/polysplenia and severe cardiac malformations characterize heterotaxy in humans. These anomalies result from the inability of the developing embryo to establish normal left-right asymmetry. We have studied an interesting family in which the heterotaxy phenotype segregates as an X-linked recessive trait. In order to map the heterotaxy locus (HTX), we have analysed 39 family members using highly-polymorphic microsatellite markers from the X chromosome. One of these markers, DXS994, shows no recombination with the disease locus in 20 informative meioses. Linkage analysis results in a maximum lod score of 6.37. Current genetic and physical mapping data assign the order of loci in Xq24-q27.1 as cen-DXS1001-(DXS994, HTX)-DXS984-tel. These results establish the first mapping assignment of situs abnormalities in humans.  相似文献   
165.
The effects of CoCl(2) on retinoic acid (RA)-treated embryoid bodies (EBs) were investigated. Four-day EBs were treated with 5x10(-6) M of RA for 4 d, then subjected to attached culturing for 7 d in the presence of CoCl(2) at 0, 20, and 100 microM. Differentiation into MAP2- and GFAP-immunopositive cells was inhibited by CoCl(2) in a dose-dependent manner. Next, RA-treated EBs were dissociated into single cells and cultured for 7 d at an initial cell density of 1x10(3)/cm(2). The number of cells increased in a CoCl(2)-dose dependent fashion. In cultures with 100 microM of CoCl(2), more than 90% of the cells were immunopositive for nestin and nestin-immunopositive cells formed clusters, while there were few cells immunopositive for MAP2 or GFAP. These results suggest that CoCl(2) inhibits neural differentiation of RA-treated EB cells and promotes the proliferation of nestin-immunopositive cells, i.e., embryonic stem (ES)-derived neural stem-like cells.  相似文献   
166.
167.
beta-Fructofuranosidase I (FFase I) formed by Aureobasidium pullulans DSM 2404 was purified. The enzyme had a molecular weight of about 430 kDa, was not affected by various metal ions and showed high transfructosylating activity. The yield of fructooligosaccharides production using purified FFase I was 62%.  相似文献   
168.
169.
Phenolic compounds (PCs) are frequently present in foods. However, little is known about the effect of PCs on enzymatic digestion process of food proteins and their products. In this study, the effect of gallic acid (GA) on in vitro digestion of β-lactoglobulin (β-LG) was investigated as a model system for analysis of the interaction between PCs and food proteins. GA showed no effect on the initial rate of β-LG digestion. However, after 1.5 h of digestion, the observed degree of hydrolysis of β-LG was lower in the presence than in the absence of GA. The peptides released from β-LG were characterized by LC/IT-TOF-MS and thirty peptides were identified. In particular, four new peaks were obtained following in vitro digestion of β-LG in the presence of GA. Met(7), Met(24) and Met(145) in the peptides corresponding to these peaks were oxidized to methionine sulfoxide residues.  相似文献   
170.
We developed a novel technique for detaching protein crystals from glass capillary tube using the counter diffusion crystallization technique by femtosecond laser irradiation. X-ray diffraction analysis demonstrated that femtosecond laser irradiation has little effect on crystallinity. This technique will contribute to progress in structural genomics as a powerful tool.  相似文献   
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