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A case of chromomycosis in which hyperthermia proved effective is reported. The patient was a 56-year-old male bean curd maker who, without any previous history of minor trauma, developed on the extensor side of the left upper arm an eczematous lesion that underwent gradual radial expansion. The lesion showed a well-defined, 7×10 cm infiltrated erythematous plaque with the central area healed and, at the upper and lower borders, adherent scales and crusts on the surface. Histological examination revealed granulomatous changes in the dermis, as well as sclerotic cells within giant cells and microabscesses. On culturing,Fonsecaea pedrosoi was isolated. The patient was treated with disposable chemical pocket warmers, which were secured over the lesion with a rather tight elastic bandage, so that they kept the affected area warm for 24 hours a day. After a month of such hyperthermic treatment, the erythema and infiltration had decreased considerably, and microscopic examination and culture of the crusts both yielded negative results. Examination of biopsy specimens of the lesion after the third month showed that it had cicatrized. The treatment was stopped after 4 months, and no relapse occurred. We also summarize the published results of local hyperthermic treatment of chromomycosis in Japan.  相似文献   
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The HLA class I antigen B44 is found in each of two different extended major histocompatibility haplotypes (allele combinations of HLA-B, HLA-DR, and complement genes BF, C2, C4A, and C4B in linkage disequilibrium). Using isoelectric focusing, two variants of HLA-B44 were identified. The basic variant was found in all cell lines with the extended haplotype HLA-B44, DR7, FC31, and the acidic variant in all cell lines with the extended haplotype HLA-B44, DR4, SC30. The occurrence of each antigen variant with a unique extended haplotype explains previous observations concerning the nonrandom association of B44 variants with DR antigens.  相似文献   
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The three-dimensional structure of acarbose bound to glycogen phosphorylase   总被引:2,自引:0,他引:2  
Acarbose, a pseudotetrasaccharide with a conduritol ring at the nonreducing terminus, is a naturally occurring inhibitor of amylases. It is shown here to be an inhibitor of glycogen phosphorylase and to bind more tightly to the enzyme than the equivalent malto-oligosaccharide substrate. X-ray crystallographic studies of the acarbose-phosphorylase a complex in the presence of glucose and caffeine reveal the structure of acarbose as bound to the storage site of phosphorylase. The acarbose binds in an orientation such that the conduritol ring makes no protein contacts. As with malto-oligosaccharides bound at this site, the observed conformation of acarbose is stabilized by O-2-O-3' hydrogen bonding and is similar to, but not identical with, that predicted by hard-sphere exo-anomeric effect calculations and justified by 1H nuclear magnetic resonance studies (Bock, K., and Pedersen, H. (1984) Carbohydr. Res. 132, 142-149). Intramolecular O2-O3' hydrogen bonds appear to play an important role in stabilizing the conformation observed in these studies, even for those residues closely associated with the protein.  相似文献   
6.
In pathogen-free mice, but not standard conventionally housed laboratory rodents, two distinctly different modes of early radiation lethality can be identified by modifying the irradiation technique (total-body versus abdominal irradiation) or by therapeutic intervention such as rescue of total-body-irradiated mice with syngeneic bone marrow or spleen. While damage to the gastrointestinal tract is usually designated as the predominant cause of death occurring within 10 days of radiation exposure, it was demonstrated that damage to the hematopoietic/lymphopoietic system can result in animal lethality over the same period as the gastrointestinal syndrome and that this target cell population is more radiation-sensitive than the gastrointestinal epithelium.  相似文献   
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The diurnal variations in the specific activities of polysaccharide-degrading enzymes after feeding were monitored in adherent and non-adherent microbial populations separated from bovine rumen liquor and digesta solids. There were marked differences in the activity profiles of the enzymes within the subpopulations. Enzymes involved in the degradation of soluble carbohydrates were more active in the non-adherent populations, and in the liquor phase subpopulation activities increased in the 1-2 h post-feed period. The muralytic enzymes were most active in the adherent population. Specific activities increased by up to 20-fold over the 24 h period, with an initial five-fold increase occurring between 8 h and 12 h after feeding. Enzyme levels in the three non-adherent populations were similar at the end of the postprandial period. In the population recovered from the liquid associated with the digesta particles, however, the activities did not increase until the latter stages of the period, whereas in the non-adherent population from the digesta solids the activities varied little during the diurnal cycle. The numbers of micro-organisms associated with the digesta solids were similar at 2 h and 20 h after feeding; the variations in enzyme levels did not occur as a result of a population increase but were due to increased activities in an established population. The plant cell wall structural polysaccharides were degraded at different rates. There was no appreciable cellulose digestion during the first 8 h of the postprandial period and although hemicellulosic constituents were removed continuously the rate of loss of both polymers was increased in the later stages of the diurnal cycle when enzyme activities were maximal.  相似文献   
8.
Butyrivibrio fibrisolvens NCFB 2249 formed xylan-degrading enzymes on a wide range of carbohydrate growth substrates. The specific activities of α-L-arabinofuranosidase and β-D-xylosidase were increased (up 20-fold) after growth on xylan or xylose-containing saccharides. Xylose was not an effective substrate for xylanase production although its formation was induced on xylobiose and higher DP xylose-containing saccharides. Acetyl esterase activity was also highest after growth on xylan. The synthesis of xylanase and β-xylosidase was repressed by glucose and hemicellulosic pentoses and although α-L-arabinofuranosidase formation was also subject to catabolite regulation, xylose did not repress its synthesis.  相似文献   
9.
Paracoccidioidomycosis was induced in immunized (IM) and non-immunized (NI) mice. The histopathology, the number of fungi in the lungs, the cellular (footpad test — FPT and macrophage inhibition factor assay — MIF) and humoral (immunodiffusion test) immune response were investigated serially postinfection. In the IM mice, at days 1 and 3, there was intense and predominant macrophagic-lymphocytic alveolitis with loose granulomatous reaction; at day 30, inflammation was mild. In the NI group, up to day 3, the lesions were focal; later there was formation of extensive epithelioid granuloma. The number of fungi in IM mice were always smaller than those of NI group. Immunization alone induced positive FPT and MIF indices with low titer of antibody. After infection, there was a significant decrease of the FPT indices in the IM group, which we interpreted as desensitization due to trapping of sensitized lymphocytes in the lungs. In conclusion, (1) The lesional pattern of pulmonary paracoccidioidomycosis in IM mice was similar to that of a hypersensitivity pneumonitis. This reaction was probably effective in reducing the extension of the infection and decrease the number of fungi. (2) In this model, pulmonary resistance against P. brasiliensis seems to be related to local and systemic delayed-type hypersensitivity reaction.  相似文献   
10.
The present study was designed to evaluate the effects of a recombinant human G-CSF (rhG-CSF) and a mutein G-CSF(KW-2228) on leucopenia and tumor growth in mice treated with 5-fluorouracil (5-FU). In normal mice, the number of leucocytes (white blood cell, WBC) reached the peak 12 hours after a single injection of either type of G-CSF and decreased to the normal level after 24 hours. Daily administration induced a continuous increase in the WBC count, however, administrations at intervals did not. Meth-A fibrosarcoma was subcutaneously inoculated into the backs of syngeneic BALB/c mice. The mice were treated with 5-FU alone or with G-CSFs. Chemotherapy with 5-FU alone resulted in leucopenia and an insignificant inhibition of tumor growth. The conjunctive administration of G-CSFs with 5-FU resulted in a significantly augmented inhibition of tumor growth, and leukopenia was not seen. This augmenting effect was more prominent with KW-2228.These results suggest that in 5-FU chemotherapy G-CSFs may be beneficial in restoring the number of leucocytes from leucopenic state and in augmenting the tumor inhibitory effect. Furthermore, KW-2228 may be more beneficial than the natural type rhG-CSF.  相似文献   
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