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排序方式: 共有6555条查询结果,搜索用时 15 毫秒
41.
Identification of two different mutations in the PDS gene in an inbred family with Pendred syndrome 总被引:11,自引:0,他引:11
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Coucke PJ Van Hauwe P Everett LA Demirhan O Kabakkaya Y Dietrich NL Smith RJ Coyle E Reardon W Trembath R Willems PJ Green ED Van Camp G 《Journal of medical genetics》1999,36(6):475-477
Recently the gene responsible for Pendred syndrome (PDS) was isolated and several mutations in the PDS gene have been identified in Pendred patients. Here we report the occurrence of two different PDS mutations in an extended inbred Turkish family. The majority of patients in this family are homozygous for a splice site mutation (1143-2A-->G) affecting the 3' splice site consensus sequence of intron 7. However, two affected sibs with non-consanguineous parents are compound heterozygotes for the splice site mutation and a missense mutation (1558T-->G), substituting an evolutionarily conserved amino acid. The latter mutation has been found previously in two Pendred families originating from The Netherlands, indicating that the 1558T-->G mutation may be a common mutation. 相似文献
42.
Development of hatching blastocysts from immature human oocytes following in-vitro maturation and fertilization using a co-culture system 总被引:8,自引:0,他引:8
Hwu YM; Lee RK; Chen CP; Su JT; Chen YW; Lin SP 《Human reproduction (Oxford, England)》1998,13(7):1916-1921
Recently, in-vitro maturation (IVM) of immature human oocytes recovered
from non-stimulated follicles has been applied in the treatment of
infertility. However, in previous reports, very few embryos cultured in
conventional medium have reached the expanded blastocyst stage following
in-vitro maturation and fertilization (IVM/IVF). The objective of this
study was to investigate whether the developmental competence of human
embryos following IVM/IVF could be enhanced by the use of a human ampullary
cell co-culture system. Immature human oocytes were aspirated from small
follicles at Caesarean section and then cultured in medium containing human
menopausal gonadotrophin for 36 to 48 h, followed by insemination. Zygotes
were randomly cultured either in conventional culture medium alone or in
the co-culture system. Of 48 embryos cultured in conventional medium alone,
all arrested at the 2-16- cell stage on day 3 after insemination. Of 46
embryos cultured in the co-culture system, 26 embryos (56.5%) arrested at
the 2-16-cell stage. Six embryos (13%) developed to the morula stage.
Fourteen embryos (30.4%) developed to expanded blastocysts and two
blastocysts were hatching on day 7 after insemination. We conclude that
co-culture significantly enhances the development of blastocysts in embryos
resulting from IVM/IVF.
相似文献
43.
Obwaller A Duchêne M Bruhn H Steipe B Tripp C Kraft D Wiedermann G Auer H Aspöck H 《Parasitology research》2001,87(5):383-389
Myosins from nematode parasites elicit strong humoral and cellular immune responses and have been investigated as vaccine candidates. In this study we cloned and sequenced a cDNA coding for myosin heavy chain from Toxocara canis, a nematode parasite of canids which may also infect humans and cause various unspecific symptoms. To determine the major antigenic regions the myosin heavy chain was systematically dissected into ten overlapping recombinant fusion polypeptides which were purified by metal chelate chromatography. Single fragments were then tested for their IgG reactivity in sera from toxocarosis patients and healthy probands. Two regions, one region at the mid to carboxy-terminal end of the head domain and one region in the rod domain, were identified as major antigens, which in combination were positive with 86% of the sera. The other domains were less reactive. This shows that the patients' IgG reactivity was not directed evenly against all parts of the molecule, but was rather clustered in few regions. 相似文献
44.
Precipitable immune complexes in healthy homosexual men, acquired immune deficiency syndrome and the related lymphadenopathy syndrome. 总被引:6,自引:0,他引:6
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Increased levels of 3% PEG precipitable circulating immune complexes (CIC) were found in healthy homosexual men, in homosexual patients with the acquired immune deficiency syndrome (AIDS), and in the AIDS related lymphadenopathy syndrome (LAS). The degree of CIC elevation increases from healthy homosexual men to LAS and AIDS. Patients suffering from AIDS associated with opportunistic infections had a more pronounced increase in CIC than patients with AIDS associated Kaposi's sarcoma. In LAS and AIDS the amount of CIC correlated with the degree of inversion of the T4/T8 lymphocyte ratio, whereas in healthy homosexual men with increased levels of CIC the T4/T8 ratio was not significantly altered. Laser nephelometric partial components analysis revealed that these complexes were of a complement poor subtype with low component levels of C4, C1q and C3c. IgM and IgG were found to be the major components. It is suggested that these CIC might represent a marker of the total antigenic burden of the immune system. Possibly, they are of prognostic and monitoring value for clinical handling of patients at risk for AIDS. 相似文献
45.
Identification and characterization of a new variant of Shiga toxin 1 in Escherichia coli ONT:H19 of bovine origin
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Bürk C Dietrich R Açar G Moravek M Bülte M Märtlbauer E 《Journal of clinical microbiology》2003,41(5):2106-2112
A new variant of Shiga toxin 1 (Stx1), designated Stx1d, which deviates considerably more than any other known variant from Stx1 encoded by phage 933J, was identified in an Escherichia coli strain, ONT:H19, isolated from bovine feces. The complete stx(1) gene of this strain was amplified and sequenced. Nucleotide sequence homology with stx(1) from phage 933J was only 91%, resulting in the substitution of 20 amino acids in the A subunit and 7 amino acids in the B subunit of the protein. Cell culture supernatant of this strain, which was negative for stx(2) by PCR testing, was cytotoxic to Vero cells and gave positive results in two commercial enzyme-linked immunosorbent assays for Stx. PCR primers were constructed for the specific detection of the new variant. The findings of this study suggest that Stx1 is not as conserved as thought before and that there might be more variants which cannot be detected by commonly used PCR methods. 相似文献
46.
Dietrich L. Meyer Dr. Detlef Bonnemann Prof. Dr. Kurt -Peter Schaefer 《Experimental brain research. Experimentelle Hirnforschung. Expérimentation cérébrale》1973,18(5):505-511
Summary Turning a rabbit on a turn-table for a few degrees induces compensatory eye-movements and results in an asymmetry of tonus in the optomotor system. If the visual input is discontinued (darkness), this asymmetry decays and the eyes drift back to the mid-position within 12–18 sec. The equalization of such asymmetries of tonus under normal conditions and under curare is described. Tonus asymmetries induced by tilting the animals about the longitudinal axis are neither compensated under visual, nor under non-visual, conditions. Recordings were taken from oculomotor neurons, and changes of their firing frequencies were used as a measure for eye movements.A preliminary report was given at the spring meeting of the German Physiological Society 1973.Supported by the Deutsche Forschungsgemeinschaft, SFB 33. 相似文献
47.
The immune response to heterologous red cells in mice: II. Antibody formation to red cells from species taxonomically related to sheep or mouse 总被引:2,自引:0,他引:2
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An attempt was made to establish the relative immunogenicity of various heterologous erythrocytes in the mouse. The immune response to multispecies red cells was examined by zone centrifugation of the antibodies, and by studying cross-reactivity between the varioys erythrocytes, time-course of haemagglutinin formation, and finally, antigen dose—antibody response relationships. As compared to sheep erythrocytes, goat erythrocytes were found to have a greatly reduced agglutinability, which merely simulated a reduced immunogenicity. However, erythrocytes from gerbil and hamster proved to be genuinely weaker antigens in the mouse. For alkylating agents, anti-metabolites and anti-mitotic compounds the drug-sensitivity of the immune response to cells of different antigenicity was not altered. 相似文献
48.
49.
Characterization of a gene encoding survival motor neuron (SMN)-related protein, a constituent of the spliceosome complex 总被引:2,自引:3,他引:2
Talbot K; Miguel-Aliaga I; Mohaghegh P; Ponting CP; Davies KE 《Human molecular genetics》1998,7(13):2149-2156
Mutations in the gene encoding the Survival Motor Neuron (SMN) protein are
responsible for autosomal recessive proximal spinal muscular atrophy (SMA).
SMN orthologues have been identified in the nematode worm Caenorhabditis
elegans and the yeast Schizosaccharomyces pombe but, to date, no human
paralogues have been described. Here we describe identification and
characterization of an SMN-related protein (SMNrp) gene that encodes a
novel protein of 239 amino acids, which has recently been identified as a
constituent of the spliceosome complex and designated SPF30. Significant
similarity to the SMN protein is apparent only within a central region of
SMNrp that represents a tudor domain. The SMNrp/SPF30 gene has been mapped
to chromosome 10q23. It is differentially expressed, with abundant levels
in skeletal muscle. An exclusively nuclear localization for SMNrp in
cultured cells and muscle sections was revealed using GFP fusion constructs
and thereafter confirmed with a polyclonal antibody raised against SMNrp.
Overexpression of SMNrp as a fusion protein in HeLa cells in culture
induced dose-dependent apoptosis with positive TUNEL staining. In addition
to a possible role for this protein as a pro-apoptotic factor, SMN and its
related protein share significant similarities in sequence and cellular
function.
相似文献
50.
Multilocus haplotype analyses reveal association between 5 novel IL-15 polymorphisms and asthma 总被引:5,自引:0,他引:5
Kurz T Strauch K Dietrich H Braun S Hierl S Jerkic SP Wienker TF Deichmann KA Heinzmann A 《The Journal of allergy and clinical immunology》2004,113(5):896-901
BACKGROUND: IL-15 is a T(H)1-related cytokine that is involved in the inflammatory response in various infectious and autoimmune diseases. IL-15 has recently been shown to be upregulated in T-cell-mediated inflammatory disorders. The observations suggest a potential role for this cytokine in a variety of pathologic conditions, including T(H)1-mediated and T(H)2-mediated inflammatory diseases. OBJECTIVE: In this study, we searched for single nucleotide polymorphisms in the whole IL-15 gene and investigated their association with inflammatory and/or atopic phenotypes. METHODS: The screening for single nucleotide polymorphisms was performed by single-strand conformation polymorphism analysis. Genotyping of the identified polymorphisms was performed by restriction fragment length polymorphism. Genotypic association analysis used the Armitage trend test. Haplotype frequency estimation and subsequent testing for differences between cases and controls were performed by using the programs FASTEHPLUS and FAMHAP. RESULTS: We identified 5 novel noncoding nucleotide sequence variants, all of which were typed in our asthmatic, our atopic, and our control population. According to the Armitage trend test, none of the 5 polymorphisms is associated with the phenotype bronchial asthma or atopy. However, multilocus haplotype analysis based on simulations to find out whether the haplotype frequencies differed between cases and controls by using the program FAMHAP yielded a P value of 6.1 x 10(-5) in the asthmatic versus the control population, which is highly significant. Furthermore, we obtained a nominally significant result of P=.0232 for the atopic versus the control population by using FAMHAP. CONCLUSION: These results strongly underscore previous findings that suggest a potential role of this cytokine in allergic diseases. 相似文献