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1.
We used ultrasonography to measure muscles in the arms and thighs of 16 children with malignant diseases. Thicknesses of transverse sections of the brachial biceps muscle and the femoral quadriceps muscle were measured by ultrasound at the midpoint of the right arm and thigh. These two measures had a linear correlation (r = 0.76). The ultrasound measurements did not differ from those obtained by the CT scan which was used as a reference standard. The reproducibility of the measurements was good; the coefficient of variation was 2.4% for the midarm muscles and 2.8% for the midthigh muscles. We conclude that the ultrasound method combined with simple anthropometric measurements is helpful in the assessment of nutritional status of children with potential malnutrition.  相似文献   
2.
DNA "fingerprint" (DNA-F) analysis, based on the polymorphism caused by numeric variations in the tandem repeats of minisatellite areas of the human genome, has a potential capacity to reveal even minor genomic changes. In this study we have applied DNA-F to the detection of residual disease in leukemia. In order to identify normal and leukemic cell populations, we used two molecular probes: Jeffrey's minisatellite probes and M13 wild type phage probe, which detect different sets of polymorphic fragments in the human genome. Comparison of varying minisatellite fragments between remission and relapse was performed by Southern blot hybridization in seven patients with acute lymphoblastic leukemia (ALL). The results suggest that Southern hybridization with DNA "fingerprint" probes can prove to be a sensitive method in the detection of minimal residual disease in ALL.  相似文献   
3.
BACKGROUND: We report on IgE-mediated allergy in a worker caused by Tribolium confusum (confused flour beetle). These beetles lived in the "old" flour to which he was exposed in his work. CASE REPORT: A 35-year-old, nonatopic mechanic in a rye crispbread factory developed rhinitis, conjunctivitis, and asthmatic symptoms, as well as urticaria on his wrists, lower arms, hands, neck, and face, during the maintenance and repair of machines contaminated by flour. This flour had been in and on the machines for a long time, and it contained small beetles. The patient did not suffer any symptoms when handling fresh, clean flour. RESULTS: Skin prick tests with standard environmental allergens, storage mites, enzymes, flours, and molds were negative. A prick test with flour from the machines gave a 10-mm reaction. An open application of the same flour caused urticarial whealing on the exposed skin. Prick tests with fresh flour from the factory were negative. A prick test with minced T. confusum from the flour in the machines gave a 7-mm reaction. Histamine hydrochloride 10 mg/ml gave a 7-mm reaction. Specific serum IgE antibodies to T. confusum were elevated at 17.2 kU/l. Prick tests with the flour from the machines were negative in five control patients. CONCLUSIONS: The patient had occupational contact urticaria, rhinitis, conjunctivitis, and asthmatic symptoms from exposure to flour. His symptoms were caused by immediate allergy to the beetle T. confusum. Immediate allergy to this beetle has rarely been reported in connection with respiratory symptoms, but it may be more common. Contact urticaria from this source has not been reported before.  相似文献   
4.
Summary: Ethylene–propylene (EP) copolymerisations were performed with two sterically different metallocenes activated by methylaluminoxane (MAO) in an attempt to better understand the effect of catalyst structure on termination reactions and polymer microstructure. The metallocene precursors under investigation were rac‐dimethylsilylbis(2‐methyl‐4‐phenyl‐1‐indenyl)zirconium dichloride ( 1 ) and a more sterically hindered counterpart rac‐dimethylsilylbis(2‐isopropyl‐4‐[3,5‐dimethylphenyl]indenyl) zirconium dichloride ( 2 ). For both catalyst systems, the most common termination mechanism was chain transfer to aluminium. In addition, for polymer samples polymerised with 1 /MAO, chain growth was terminated by chain transfer to Zr metal in propylene‐rich polymerisations and by chain transfer to ethylene monomer in ethylene‐rich polymerisations. The steric hindrance of 2 was able to suppress the chain transfer to the ethylene monomer, and chain transfer to Zr metal was also found in the ethylene‐rich polymerisations. The greater steric hindrance of 2 also affected the EP copolymer microstructure: regioregularity in the propylene‐rich copolymers was greater and isotacticity less with 2 /MAO than with 1 /MAO.

The catalyst precursors used: rac‐dimethylsilylbis(2‐methyl‐4‐phenyl‐1‐indenyl)zirconium dichloride ( 1 ) and rac‐dimethylsilylbis(2‐isopropyl‐4‐[3,5‐dimethylphenyl]indenyl) zirconium dichloride ( 2 ).  相似文献   

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IgE antibodies distinctively recognising allergenic epitopes would be ideal reagents in immunodiagnostics to detect and quantify allergens, as well as for the development of allergy diagnostics and therapeutics. We have isolated recombinant human IgE antibodies specific for the major latex allergen, hevein, from antibody phage display libraries using a green fluorescent protein (GFP)-hevein fusion as a selection antigen. Human IgE phage display libraries were constructed by combining the IgE heavy chain genes to kappa and lambda light-chain genes which were isolated from lymphocytes of a latex allergic patient. The screening of antibody libraries resulted in the enrichment of two hevein-binding scFvs designated as 1A4 and 1C2. Both antibodies showed specific binding to the hevein that could be inhibited by both the recombinant GFP-hevein and native hevein isolated from latex examination gloves. The scFvs were prone to aggregate and, thus, for further characterisation, they were converted to Fab fragments with human IgG1 or IgE isotype. Similar hevein-binding properties of the 1A4 and 1C2 Fab fragments and human IgE serum pool, conventionally used in the detection of latex allergens, demonstrate the potential utility of these recombinant antibodies for the analysis of latex allergen.  相似文献   
8.
The expression of the disialoganglioside GD2 was analyzed in 67 solid tumors and normal tissues from children by using the GD2-specific murine monoclonal antibody 3A7 and the indirect immunoperoxidase method. GD2 was expressed in all of 28 neuroblastomas and was most abundant in stroma-poor tumors. In differentiating stroma-rich neuroblastomas, neuroblastic clusters, neurofibrils, and most ganglion-like cells were positive, whereas Schwann's-cell stroma did not express GD2. In ganglioneuromas, only a few ganglion-like cells showed GD2, whereas all other structures were negative. Scattered foci of ganglioside GD2 also were found in some non-neuronal tumors, such as rhabdomyosarcomas and osteosarcomas, but not in lymphomas, Askin tumors, or most Wilms' tumors. The monoclonal antibody 3A7 is a useful aid in the immunohistochemical diagnosis of neuroblastoma. In addition, the intense cell surface staining of neuroblastoma cells by this reagent makes it potentially useful for detecting residual neuroblastoma in bone marrow samples and lymph node biopsies.  相似文献   
9.
We have identified a novel missense transition (362G→A) in exon 3 of the COL4A5 gene in a male patient with late-onset Alport syndrome. We used non-isotopic single strand conformation polymorphism, heteroduplex analysis, and automated DNA sequencing. The mutation changes a conserved glycine at codon 54 for an aspartic acid (Gly54Asp), which abolishes a BstNI site. Using restriction analysis, we identified the heterozygous carrier status in the two daughters of the proband. Our findings are in keeping with the hypothesis that slower progressive forms of Alport syndrome are more often associated with missense mutations rather than large deletions or frameshifts. This is the first mutation described in the N-terminus triple helical 7S domain of the COL4A5 gene in an Alport syndrome patient.  相似文献   
10.
Strains (n = 203) of Yersinia species were used in genotyping and PCR experiments in order to evaluate the genotyping potential of the YeO:3RS probe. This probe comprises a 12.5 kb genomic fragment of the Y. enterocolitica O:3 lipopolysaccharide O-antigen gene cluster cloned into plasmid pBR322. The genotyping potential of YeO:3RS was shown to reside in the region upstream of the O-antigen gene cluster, i.e., in the first 1.65 kb of the cloned genomic fragment that contains a repeated sequence (RS) present in multiple copies in the genome. In genotyping, the YeO:3RS probe was hybridised to DNA of Yersinia enterocolitica isolates (n = 112) from humans, animals and food, along with strains of other Yersinia species (n = 5) and Salmonella enterica strains (n = 3). The YeO:3RS probe efficiently detected and subtyped all European pathogenic Yersinia enterocolitica isolates of the serobiotypes O:3/4, O:9/2 and O:5,27/2 studied (n = 87), whereas it hybridised only weakly or not at all with the other strains. Within Yersinia enterocolitica serobiotype O:3/4 strains, YeO:3RS genotyping was as discriminatory as genotyping by pulsed-field gel electrophoresis (PFGE) of XbaI-NotI digested genomic DNA. When these two methods were combined, YeO:3RS genotyping divided both of the two predominant PFGE types into six subtypes, thus increasing the discrimination. In PCR screening of additional 86 Yersinia strains, the 1.65 kb region was detected in European pathogenic serotypes O:1 and O:2 in addition to serotypes O:3, O:5,27 and O:9, indicating that it can be exploited in detecting and typing of European pathogenic serotypes in general.  相似文献   
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