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91.
The first Japanese En(a-) individual (T.N.) was found by screening red cells from 250,000 Japanese blood donors with monoclonal anti-Ena. His serum contained no atypical antibodies and his partial red cell phenotype was M-N-S+s-, although a trypsin- resistant N antigen was detected. His red cells were En(a-) and Wr(b-), as determined by various human and mouse monoclonal antibodies. The absence of glycophorin A (GPA) and the presence of apparently normal glycophorin B (GPB) were demonstrated by immunoblotting with antibodies to the extracellular and cytoplasmic domain of GPA and to epitopes common to GPA and GPB. Sialic acid levels of T.N.'s intact red cells were substantially lower than those of control MN cells. Serologic tests suggested that both of T.N.'s parents were heterozygous for a recessive GPA deficiency gene.  相似文献   
92.
Background: No published studies have compared the effectiveness of several treatments proposed to reduce cat allergenicity. Cat washing studies demonstrating efficacy involved very small sample sizes or infrequent washings. Allerpet-C (Allerpet, Inc., New York, N.Y.), a widely advertised topical spray, and acepromazine, a tranquilizer advocated as efficacious in subsedating doses, have never been scientifically studied. Objective: We compared the effects of cat washing, Allerpet-C spray, and acepromazine with that of no treatment on the shedding of the primary cat allergen, Felis domesticus I by cats. Methods: In a blinded, comparative, controlled study, we measured the amounts of Fel d I shed during an 8-week treatment period with a sample of 24 female mongrel cats randomly assigned to four groups; one group received weekly distilled water washings, one received weekly Allerpet-C spray applications, one received daily oral acepromazine, and one had no treatment (control). Thirty-minute, twice-weekly air samples were collected from each cat with a laminated plastic–acrylic chamber and air sampler. Results: One-sample, two-sided t tests comparing baseline to final-week measurements revealed no significant change in Fel d I within each group (mean change ±SD: washing; 487.6 ± 1896.4 mU per 30 minutes, p = 0.63; Allerpet-C spray, 429.2 ± 871.6 mU per 30 minutes, p = 0.46 acepromazine; −620.6 ± 1031.2, p = 0.52 per 30 minutes). Furthermore, analysis of covariance revealed no significant change in Fel d I levels between groups (p = 0.72). Conclusions: Our data do not show significant reductions in Fel d I shedding as a result of any of these treatments. Therefore we cannot recommend them to patients allergic to cats. (J ALLERGY CLIN IMMUNOL 1995;95:1164-71.)  相似文献   
93.
94.
We have used the “allogeneic effect” as a model system for investigating the effects of augmented thymus-derived lymphocyte function on secondary antibody responses of primed inbred guinea pigs. A transient graft-versus-host reaction was induced by infusing nonimmune strain 13 lymphoid cells into strain 2 guinea pigs which had been primed with dinitrophenylated (DNP) ovalbumin. Six days later the recipients were challenged with the priming antigen intradermally. Four days after boosting with antigen, sera from these “allogeneic” guinea pigs had significantly higher affinity for ε-DNP-L -lysine than sera from “control” guinea pigs which were primed, but had not received allogeneic lymphoid cells. Spleen cells taken from “allogeneic” guinea pigs three to five days after boosting were shown to have both higher numbers of plaque-forming cells and a predominance of high avidity antibody-producing cells in comparison to spleen cells from “control” guinea pigs. Thus, increased donor thymus-derived lymphocyte function brought about by the transient graft-versus-host reaction causes an enlargement of the host antibody-producing cell pool and preferentially expands the subpopulation of cells producing high affinity antibody. The effects of this preferential expansion are reflected in the sera of “allogeneic” guinea pigs as higher affinity antibody in comparison to serum antibody of “control” guinea pigs.  相似文献   
95.
Three cases of Down syndrome (DS) are reported in association with features of the androgen insensitivity syndrome (AIS). All were 47, XY, +21 and reared as females. One case had a normal female phenotype, and two cases showed minimal clitoromegaly and labial fusion. Minor genital underdevelopment has been reported as common in males with DS; however, AIS has not previously been associated with DS. Androgen binding studies in genital skin fibroblasts were normal in two cases and in the 46,XY brother of the third who has perineal hypospadias. Mutation screening of the androgen receptor (AR) gene by PCR-SSCP was normal in all cases. Normal androgen binding and the absence of an identified mutation in the coding region of the AR gene is very unusual in AIS, particularly in the complete form. This finding suggests the operation of hitherto unrecognised genes on chromosome 21 with a role in androgen response and sex differentiation.  相似文献   
96.
97.
U2AF homology motifs: protein recognition in the RRM world   总被引:11,自引:0,他引:11  
Recent structures of the heterodimeric splicing factor U2 snRNP auxiliary factor (U2AF) have revealed two unexpected examples of RNA recognition motif (RRM)-like domains with specialized features for protein recognition. These unusual RRMs, called U2AF homology motifs (UHMs), represent a novel class of protein recognition motifs. Defining a set of rules to distinguish traditional RRMs from UHMs is key to identifying novel UHM family members. Here we review the critical sequence features necessary to mediate protein-UHM interactions, and perform comprehensive database searches to identify new members of the UHM family. The resulting implications for the functional and evolutionary relationships among candidate UHM family members are discussed.  相似文献   
98.
99.
B1 vitamin deficiency was studied by the erythrocyte enzyme activation test in patients with chronic uraemia. Transketolase activity was measured in the erythrocyte haemolysates of 14 patients with chronic uraemia and in 16 healthy controls in the presence of TPP and following TPP saturation. The magnitude of activity increases as a result of TPP saturation which is probably indicative of an insignificant thiamine deficiency in patients with chronic uraemia.  相似文献   
100.
An ordered comparative map of the cattle and human genomes   总被引:14,自引:2,他引:14       下载免费PDF全文
A cattle-human whole-genome comparative map was constructed using parallel radiation hybrid (RH) mapping in conjunction with EST sequencing, database mining for unmapped cattle genes, and a predictive bioinformatics approach (COMPASS) for targeting specific homologous regions. A total of 768 genes were placed on the RH map in addition to 319 microsatellites used as anchor markers. Of these, 638 had human orthologs with mapping data, thus permitting construction of an ordered comparative map. The large number of ordered loci revealed > or =105 conserved segments between the two genomes. The comparative map suggests that 41 translocation events, a minimum of 54 internal rearrangements, and repositioning of all but one centromere can account for the observed organizations of the cattle and human genomes. In addition, the COMPASS in silico mapping tool was shown to be 95% accurate in its ability to predict cattle chromosome location from random sequence data, demonstrating this tool to be valuable for efficient targeting of specific regions for detailed mapping. The comparative map generated will be a cornerstone for elucidating mammalian chromosome phylogeny and the identification of genes of agricultural importance."Ought we, for instance, to begin by discussing each separate species-in virtue of some common element of their nature, and proceed from this as a basis for the consideration of them separately?" from Aristotle, On the Parts of Animals, 350 B.C.E.  相似文献   
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