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991.
Jagodzinski PP Lecybył R Ignacak M Juszczyk J Trzeciak WH 《Journal of human genetics》2000,45(5):271-274
The chemokine receptor CCR5 constitutes a major co-receptor for the R5 strains of HIV-1, and a mutant allele of the CCR5 gene, especially in the homozygous form Δ32/Δ32, confers resistance against infection by the virus. The frequency of the
Δ32 allele was determined in blood donors from 16 provinces, covering the entire territory of Poland. Among 861 individuals
182 (21.1%) were carriers of the mutated allele; 7 of them (0.8 %) were homozygotes Δ32/Δ32, and 175 (20.3%) were heterozygotes
+/Δ32, resulting in a 10.9% frequency of the Δ32 allele. The highest frequencies of the mutated allele were found in the eastern
and western provinces, and the lowest frequencies of the Δ32 allele were detected in the provinces in the center of the country.
This pattern of distribution may reflect the migration of the population from the eastern territories of Poland to the western
part of the country after World War II.
Received: March 17, 2000 / Accepted: May 29, 2000 相似文献
992.
小陷胸汤加味含药血清对人脐静脉内皮细胞分泌NO/ET-1的调节作用 总被引:3,自引:1,他引:3
目的:探讨小陷胸汤加味中药方对血管内皮细胞的保护作用。方港:建立ox-LDL损伤人脐静脉内皮细胞株(ECV-304)模型,用小陷胸汤加味含药血清处理模型,并用放免和硝酸酶还原法在药物干预6h和24h后检测细胞上清液中ET-1和NO含量。结果:100 μg/ml的ox-LDL可损伤血管内皮细胞并导致其分泌NO和ET-1功能失调,小陷胸汤加味含药血清通过影响NO/ET-1的分泌而明显改善此失调状态。结论:小陷胸汤加味中药通过调节NO/ET-1水平显著拮抗ox-LDL对血管内皮细胞损害,具有防治AS的作用。 相似文献
993.
Chin Han Chan Claudia Kummerlwe Hans‐Werner Kammer 《Macromolecular chemistry and physics.》2004,205(5):664-675
Summary: Blends of high molecular weight poly(R‐3‐hydroxybutyrate) (PHB) ( = 352 000 g · mol?1), comprising of either low molecular weight poly(R‐3‐hydroxybutyrate) (D‐PHB) ( = 3 900 g · mol?1) or poly[(R‐3‐hydroxybutyrate)‐co‐(R‐3‐hydroxyvalerate)] (PHBV) ( = 238 000 g · mol?1) with 12 mol‐% hydroxyvalerate (HV) content as a second constituent, were investigated along with the thermal properties and morphologies. After isothermal crystallization, a lowering of the melting temperature of PHB can be observed with increasing content of the second component in the blends. This behavior points towards miscibility of the constituents both in the liquid and the solid state. Crystallization kinetics was studied under isothermal and non‐isothermal conditions. The overall kinetics of isothermal crystallization was analyzed in terms of the Avrami equation. Only one crystallization peak is observed in all cases for the PHB/D‐PHB and PHB/PHBV blends under the conditions studied. This demonstrates co‐crystallization of the constituents. The addition of D‐PHB or PHBV to PHB reduces the rate of crystallization of the blends compared to that of neat PHB. The corresponding activation energies of crystallization also decrease with an increasing concentration of the second constituent. Non‐isothermal crystallization, carried out with different cooling rates held constant, is discussed in terms of a quasi‐isothermal approach. The corresponding rate constants as functions of reciprocal undercooling show Arrhenius‐like behavior in a certain range of temperatures. At sufficiently high undercooling, the rate constants of crystallization for the isothermal process exceed those reflecting non‐isothermal conditions, whereas in the limit of low undercoolings, the rate constants become similar. Ring‐banded morphologies are observed when PHB is in excess. When the respective second component is the major component, fibrous textures of the spherulites develop.
994.
Aidan P. McManus Barry A. Gusterson C. Ross Pinkerton Janet M. Shipley 《The Journal of pathology》1995,176(2):137-142
It is increasingly recognized that the identification of t(11;22)(q24;q12) is a useful aid in the accurate diagnosis of Ewing's sarcoma and related tumours. However, cytogenetic studies have a low success rate and adequate tumour is not always available. This study describes the use of fluorescence in situ hybridization (FISH) to detect translocations at 22q12, the site of the EWS gene involved in t(11;22)(q24;q12), on tumour touch imprints made from true cut core-needle biopsy and frozen tumour. Of the seven tumours analysed, five diagnosed as Ewing's sarcoma or primitive neuroectodermal tumour demonstrated chromosome translocation at 22q12. This is a rapid and reliable method to detect a diagnostically relevant chromosome translocation using minimal amounts of fresh or frozen tumour. 相似文献
995.
Perrin C. White Maria-Teresa Tusie-Luna Maria I. New Phyllis W. Speiser 《Human mutation》1994,3(4):373-378
The inherited inability to synthesize cortisol is termed congenital adrenal hyperplasia. More than 90% of cases are caused by 21-hydroxylase deficiency. This syndrome is characterized by signs of androgen excess and often mineralocorticoid deficiency. Steroid 21-hydroxylase (P450c2l) is a microsomal enzyme expressed in the adrenal gland that catalyzes conversion of 17-hydroxyprogesterone and progesterone to 11-deoxycortisol and deoxycorticosterone respectively. In man, this enzyme is encoded by the CYP21 (CYP21B) gene which is located in the HLA major histocompatibility complex along with a pseudogene, CYP21P (CYP21A). Mutations in CYP21 causing congenital adrenal hyperplasia are almost all generated by recombinations between CYP21 and CYP21P. These recombinations either delete CYP21 or transfer deleterious mutations from CYP21P to CYP21, a process termed apparent gene conversion. The degree of enzymatic compromise caused by each mutation is correlated with the clinical severity of the deficiency observed in patients carrying that mutation. © 1994 Wiley-Liss, Inc. 相似文献
996.
Yusuf Orhan Adil Azezli Mahmut Çarin Ferihan Aral Ergin Sencer Senay Molvalılar 《Journal of clinical immunology》1993,13(5):339-343
To evaluate the association of HLA types with Turkish patients with Graves' disease, HLA typing, clinical findings, and thyroid antibodies were correlated. The HLA types, clinical findings (ophthalmopathy and age at onset), and thyroid stimulating hormone (TSH) receptor (TRAb) and antithyroid microsomal antibodies (MAb) were analyzed. Seventy Turkish patients with Graves' disease and 306 control subjects were assessed. Serological HLA typing was performed in HLA A, B, C, DR, and DQ loci. There was a significantly increased prevalence of HLA B8, B49, DR3, DR4, and DR10 in Graves' disease. The association of Graves' disease with HLA DR3 was found to be less strong than previously described. The HLA DR4 antigen may contribute to the predisposition of Graves' disease in Turkey. The results suggest that HLA B7, B13, DR7, DQw2, and DQw3 may confer a protective effect for Graves' disease in Turkey. Patients carrying HLA B12, B18, and B44 haplotypes had a tendency to develop the disease at a later age. The difference from the other studies may be the result of the selection of the controls; in part, of the variability in serological typing reagents; and, also, of the rather weak HLA associations with the disease.This study was presented in part at the Annual Meeting of the National Endocrinology and Diabetes Association, Bursa, Turkey, May 25–28, 1992. 相似文献
997.
Linkage exclusion and mutational analysis of the noggin gene in patients with fibrodysplasia ossificans progressiva (FOP) 总被引:1,自引:0,他引:1
Xu MQ Feldman G Le Merrer M Shugart YY Glaser DL Urtizberea JA Fardeau M Connor JM Triffitt J Smith R Shore EM Kaplan FS 《Clinical genetics》2000,58(4):291-298
Fibrodysplasia ossificans progressiva (FOP) is an extremely rare and disabling genetic disorder characterized by congenital malformation of the great toes and by progressive heterotopic endochondral ossification in predictable anatomical patterns. Although elevated levels of bone morphogenetic protein 4 (BMP4) occur in lymphoblastoid cells and in lesional cells of patients with FOP, mutations have not been identified in the BMP4 gene, suggesting that the mutation in FOP may reside in a BMP4-interacting factor or in another component of the BMP4 pathway. A powerful antagonist of BMP4 is the secreted polypeptide noggin. A recent case report described a heterozygous 42-bp deletion in the protein-coding region of the noggin gene in a patient with FOP. In order to determine if noggin mutations are a widespread finding in FOP, we examined 31 families with 1 or more FOP patients. Linkage analysis with an array of highly polymorphic microsatellite markers closely linked to the noggin gene was performed in four classically-affected multigenerational FOP families and excluded linkage of the noggin locus to FOP (the multipoint lod score was -2 or less throughout the entire range of markers). We sequenced the noggin gene in affected members of all four families, as well as in 18 patients with sporadic FOP, and failed to detect any mutations. Single-strand conformation polymorphism (SSCP) analysis of 4 of these patients plus an additional 9 patients also failed to reveal any mutations. Among the samples analyzed by SSCP and DNA sequencing was an independently obtained DNA sample from the identical FOP patient previously described with the 42-bp noggin deletion; no mutation was detected. Examination of the DNA sequences of 20 cloned noggin PCR products, undertaken to evaluate the possibility of a somatic mutation in the noggin gene which could be carried by a small subset of white blood cells, also failed to detect the presence of the reported 42-bp deletion. We conclude that mutations in the coding region of noggin are not associated with FOP. 相似文献
998.
Phylogenetic relationships among Ampelomyces isolates, pycnidial hyperparasites and biological control agents of powdery mildews, were inferred from internal transcribed
spacer (ITS) sequences of the ribosomal DNA (rDNA). Currently, these hyperparasites are considered to be a single species,
A. quisqualis, despite observed morphological and cultural differences. Ten Ampelomyces isolates, representing seven previously defined ITS RFLP groups, were sequenced and analyzed. Sequence-divergence values
among isolates belonging to different RFLP groups ranged from 4.3 to 22.4%, suggesting that these isolates may represent different
taxa. When Ampelomyces ITS sequences were analyzed by cladistic methods with the sequences of other ascomycetous fungi, they formed two lineages
in the Dothideales. Slow-growing Ampelomyces isolates formed a clade with Leptosphaeria microscopica and L. nodorum, whereas fast-growing Ampelomyces isolates formed a clade with Epicoccum nigrum. Sequence-divergence values between these two clades ranged from 17.3 to 22.4%, suggesting that the taxa in the two clades
are not closely related and possibly not congeneric. The data presented here indicate that the identification of `A. quisqualis' isolates used in biological control experiments should be re-evaluated.
Received: 10 March 1997 / Accepted: 13 February 1998 相似文献
999.
1000.
Liposomes could bind and fuse efficiently to human erythrocytes in the presence of HVJ when they contained gangliosides isolated from human erythrocytes. Sialosylparagloboside, which has a terminal sequence of NeuAcα2?3Ga1β1?4GlcNac, has a much higher receptor activity to the virus than GD1a, GD1b, GT1b, and GT1a, all of which contain the terminal sequence of NeuAcα2?3Galβ1?3GalNAc or NeuAcα2?8NeuAcα2?3Galβ1?3GalNAc. The activity of sialosylparagloboside is comparable to that of glycophorin, a major sialoglycoprotein of human erythrocytes, when compared on the basis of the required amount (as sialic acid) of compounds. The high affinity of sialosylparagloboside to the viral HANA protein is also suggested by the finding that it showed high inhibitory activity against HVJ-mediated binding of glycophorin liposomes to erythrocytes. Sialosylparagloboside was also highly susceptible to the viral sialidase, the other biological function of HANA protein. 相似文献