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71.
Interaction of adenosine and its phosphorylated derivatives with putative purinergic receptors in the gill vascular bed of rainbow trout 总被引:1,自引:0,他引:1
1. The haemodynamic responses of trout gill to pulses of adenosine and related nucleotides were recorded in isolated trout head preparations. 2. Pulses of adenosine and related nucleotides induced a vasoconstriction of arterial gill vessels. Theophylline antagonized the resonse to adenosine but had not influence on its metabolism. 3. Dipyridamole and two adenosine deaminase inhibitors [deoxycoformycin and erythro-9(2-hydroxy-3-nonyl) adenine] had no effect on either the haemodynamic response of adenosine or its deamination and its uptake by gill tissues. 4. The adenosine response was neither mediated by cholinergic nor adrenergic receptors. 5. These results suggest the existence of extracellular "purinergic receptors" in the gills of trout. 相似文献
72.
Hao Wang Ingeborg Barisic Maria Loane Marie‐Claude Addor Linda M. Bailey Miriam Gatt Kari Klungsoyr Olatz Mokoroa Vera Nelen Amanda J. Neville Mary O'Mahony Anna Pierini Anke Rissmann Christine Verellen‐Dumoulin Hermien E.K. de Walle Awi Wiesel Katarzyna Wisniewska Lolkje T.W. de Jong‐van den Berg Helen Dolk Babak Khoshnood Ester Garne 《American journal of medical genetics. Part A》2019,179(4):595-601
We aimed to assess prevalence, birth outcome, associated anomalies and prenatal diagnosis of congenital clubfoot in Europe using data from the EUROCAT network, and to validate the recording of congenital clubfoot as a major congenital anomaly by EUROCAT registries. Cases of congenital clubfoot were included from 18 EUROCAT registries covering more than 4.8 million births in 1995–2011. Cases without chromosomal anomalies born during 2005–2009, were randomly selected for validation using a questionnaire on diagnostic details and treatment. There was 5,458 congenital clubfoot cases of which 5,056 (93%) were liveborn infants. Total prevalence of congenital clubfoot was 1.13 per 1,000 births (95% CI 1.10–1.16). Prevalence of congenital clubfoot without chromosomal anomaly was 1.08 per 1,000 births (95% CI 1.05–1.11) and prevalence of isolated congenital clubfoot was 0.92 per 1,000 births (95% CI 0.90–0.95), both with decreasing trends over time and large variations in prevalence by registry. The majority of cases were isolated congenital clubfoot (82%) and 11% had associated major congenital anomalies. Prenatal detection rate of isolated congenital clubfoot was 22% and increased over time. Among 301 validated congenital clubfoot cases, diagnosis was confirmed for 286 (95%). In conclusion, this large population‐based study found a decreasing trend of congenital clubfoot in Europe after 1999–2002, an increasing prenatal detection rate, and a high standard of coding of congenital clubfoot in EUROCAT. 相似文献
73.
Chapiro E Feldmann D Denoyelle F Sternberg D Jardel C Eliot MM Bouccara D Weil D Garabédian EN Couderc R Petit C Marlin S 《European journal of human genetics : EJHG》2002,10(12):851-856
Hearing impairment is the most frequent sensory defect in children, with a genetic basis in about 50% of cases. Several point mutations and deletions in mitochondrial DNA (mtDNA) have been identified in non-syndromic sensorineural hearing loss (NSSNHL). Beside the frequent A1555G mutation, a number of mutations in tRNAs have been reported recently, but their incidence remains unknown. We identified the T7511C mutation in the tRNASer(UCN) gene in two French families with isolated deafness. Maternal transmission was obvious in both. The 15 patients with hearing impairment exhibited a variable disease phenotype in terms of onset, severity, and progression. T7511C was present in all the patients screened. Homoplasmic and heteroplasmic levels were observed and did not correlate with the severity of the disease. T7511C was also present in 12 hearing offspring of the oldest deaf mothers, confirming the existence of modulatory factors. Our data suggest that this mtDNA mutation should be screened for in all cases of familial NSSNHL compatible with maternal transmission. 相似文献
74.
Frints SG Jun L Fryns JP Devriendt K Teulingkx R Van den Berghe L De Vos B Borghgraef M Chelly J Des Portes V Van Bokhoven H Hamel B Ropers HH Kalscheuer V Raynaud M Moraine C Marynen P Froyen G 《American journal of medical genetics. Part A》2003,(3):367-374
We describe a 59-year-old male (patient A059) with moderate to severe mental retardation (MR) and a pericentric inversion of the X-chromosome: inv(X)(p21.1;q22.1). He had short stature, pectus excavatum, general muscle wasting, and facial dysmorphism. Until now, no other patients with similar clinical features have been described in the literature. Molecular analysis of both breakpoints led to the identification of a novel "Nuclear RNA export factor" (NXF) gene cluster on Xq22.1. Within this cluster, the NXF5 gene was interrupted with subsequent loss of gene expression. Hence, mutation analysis of the NXF5 and its neighboring homologue, the NXF2 gene was performed in 45 men with various forms of syndromic X-linked MR (XLMR) and in 70 patients with nonspecific XLMR. In the NXF5 gene four nucleotide changes: one intronic, two silent, and one missense (K23E), were identified. In the NXF2 gene two changes (one intronic and one silent) were found. Although none of these changes were causative mutations, we propose that NXF5 is a good candidate gene for this syndromic form of XLMR, given the suspected role of NXF proteins is within mRNA export/transport in neurons. Therefore, mutation screening of the NXF gene family in phenotypically identical patients is recommended. 相似文献
75.
Flat urothelial lesions of the urinary bladder have been recently discussed by the International Society of Urological Pathology (ISUP) in 1998 and more recently redefined by an international consultation held in Ancona, Italy in 2001. This paper summarizes and illustrates the recent literature about non-papillary lesions of the urinary bladder. Flat urothelial lesions include: epithelial abnormalities (reactive urothelial atypia and flat hyperplasia), preneoplastic lesion (dysplasia) and neoplastic non invasive carcinoma (carcinoma in situ) and a new category of presumed neoplastic lesions and conditions; the latter points out to a notion of tumor biology, which may help to the understanding of urothelial carcinogenesis. 相似文献
76.
Thierry Janssen MD Michel Petein MD Roland van Velthoven MD Patrick van Leer MD Marc Fourmarier MD Juan-Pablo Vanegas MD Andre Danguy PhD Claude Schulman MD Jean-Lambert Pasteels MD Robert Kiss PhD 《Human pathology》1996,27(12):1341-1347
The histochemical binding pattern of the peanut (Arachis hypogaea) lectin (PNA) was quantitatively described by means of computer-assisted microscope analysis in 28 benign prostatic hyperplasias (BPH), 15 prostatic intraepithelial neoplasias (PIN), and 119 prostatic adenocarcinomas. PNA exhibits noninunune but selective binding to glycoproteins with β-D-galactosyl(1,3)-N-acetyl-D-galactosamine residues. We also investigated whether a relationship existed between the number of histochemical-related PNA acceptors and the histochemical prostate-specific antigen (PSA) stain intensity, and between the number of PNA receptors and DNA ploidy level. The results show that neoplastic prostate tissues and high-grade intraepithelial prostatic neoplasias (PIN2_3) exhibit a significantly higher number of PNA acceptors than benign prostatic hyperplasias and low (PIN1) grade prostatic intraepithelial neoplasias. A statistically significant correlation was observed between the number of histochemically related PNA acceptors and PSA immunostain intensity. Lastly, diploid prostatic tumors, whether benign or malignant, exhibited a significantly higher number of PNA acceptors than aneuploid ones. These results suggest that PNA acceptors play an important role in the biology of prostate tumors. 相似文献
77.
78.
Karine Petitprez Jean-Marie Grzych Christine Pierrot Claude Godin André Capron Jamal Khalife 《Parasitology research》1997,84(1):38-40
Genes encoding the heavy and light chains of an anti-idiotype antibody (AB2) mimicking a protective oligosaccharide of Schistosoma mansoni were cloned and expressed as a single-chain Fv fragment. The expression in a functional state was tested using the AB1. A
specific binding between sFv and AB1 was observed. Immunization with the recombinant AB2 indicates its capacity to elicit
anti-S. mansoni antibodies.
Received: 28 April 1997 / Accepted: 24 June 1997 相似文献
79.
Summary Southern blot analysis of AvaI-digested total cellular DNA from the interfertile species Chlamydomonas eugametos and Chlamydomonas moewusii with a coxI mitochondrial gene probe from Chlamydomonas reinhardtii revealed single hybridizing fragments of 5.0 and 3.5 kb, respectively. The transmission of these mitochondrial DNA physical markers along with that of chloroplast genetic markers for resistance to streptomycin and resistance to erythromycin was studied in the fourth backcrosses of F1 hybrids to one or the other parent. Viability in these backcrosses is high in contrast to the cross C. eugametos x C. moewusii and its reciprocal which are associated with considerable meiotic product lethality. The resulting zygospores were found to transmit the mitochondrial and chloroplast genome markers uniparentally or preferentially from the mating-type-plus parent. Thus the species pair C. eugametos and C. moewusii differs from the pair Chlamydomonas reinhardtii and Chlamydomonas smithii in which mitochondrial genome markers are transmitted uniparentally by the mating-type minus parent, while the chloroplast genome markers are transmitted uniparentally by the opposite parental mating-type (Boynton et al. 1987). 相似文献
80.