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91.
92.
R. F. Sellers Lesley M. Burt Alison Cumming Doreen L. Stewart 《Archives of virology》1960,9(5):637-646
Summary Strains of the virus of foot-and-mouth disease obtained from different hosts and tissue cultures were tested in tissue cultures of pig, calf, ox and lamb kidneys for their ability to multiply and produce cytopathogenic effects. It was found that whereas cattle and kidney strains of the virus multiplied well in the cultures with cytopathogenic effect, mouse and egg adapted strains did not multiply or show cytopathogenic effect to the same extent especially in the ox and calf kidneys, and this could be correlated with their behaviour in cattle, pigs and cattle tongue epithelium tissue cultures. With all the strains used it was found possible to produce plaques on pig kidney monolayers, but the size and shape of the plaque varied as well as the relation of plaque titre to the titre in mice. The plaque size and plaque population from different sources were compared, and it was found that the relative number of the different plaque sizes varied with the source of the virus and changed in passage in the different systems. The possible significance of these findings in relation to vaccine preparation and adaptation of the virus is discussed.Part of the work described represents the kidney tissue culture side of experiments on attenuated strains of the virus of foot-and-mouth disease. We are grateful to our colleagues at Pirbright for the supply of virus strains and the results of many cattle, egg and mouse titrations.We would also like to thank MissP. Tremayne-Smitli, Mr.W. Chapman and Mr.D. Maskell for their excellent assistance in this work. 相似文献
93.
Genetic and physical characterization of the early-onset Alzheimer's disease AD3 locus on chromosome 14q24.3 总被引:1,自引:0,他引:1
Cruts Marc; Backhovens Hubert; Theuns Jessie; Clark Robert F.; Le Paslier Denis; Weissenbach Jean; Goate Alison M.; Martin Jean-Jaques; Van Broeckhoven Christine 《Human molecular genetics》1995,4(8):1355-1364
Genetic linkage studies have provided significant evidence thata major gene defect, AD3, for familial early-onset Alzheimer'sdisease (EOAD) is located at chromosome 14q24.3, between theshort tandem repeat (STR) markers D14S52 and D14S53 defininga genetic size of 22.7 cM for the AD3 candidate region. We constructeda physical map of the AD3 region using yeast artificial chromosomes(YACs) selected from both the CEPH and megaCEPH YAC librariesusing the AD3 linked STR markers as well as new sequence-taggedsites (STSs) designed based on YAC terminal sequences. The YACmap is contiguous in the region between D14S258 and D14S53,a region of 8.2 cM, and has an estimated physical size of 48Mb. The YAC contig map was used as a framework to localize threeknown genes, a pseudogene and two brain expressed sequence tags(ESTs). Linkage analysis studies in two Belgian chromosome 14EOAD families AD/A and AD/B, identified obligate recombinantsin family AD/A with D14S289 and D14S61 reducing the geneticsize of the candidate AD3 region substantially. The minimalAD3 candidate region measured 6.4 cM on the genetic map andis contained within six overlapping megaCEPH YACs that covereda physical distance estimated between 2 and 6 Mb. These YACsas well as other YACs in the YAC contig map are valuable resourcesin gene cloning efforts or genomic sequencing experiments aimingat isolating the AD3 gene. 相似文献
94.
Metes D Logar A Rudert WA Zeevi A Woodward J Demetris AJ Abu-Elmagd K Eghtesad B Shapiro R Fung JJ Trucco M Starzl TE Murase N 《Human immunology》2003,64(8):787-795
Passenger leukocytes have been demonstrated to play significant roles in initiating and also regulating immune reactions after organ transplantation. Reliable techniques to detect donor leukocytes in recipients after organ transplantation are essential to analyze the role, function, and behavior of these leukocytes. In this report we describe a simple, reliable method to detect donor cells with low frequencies using peripheral blood samples. Detection of small numbers of major histocompatibility complex (MHC) mismatched cells was first studied using four-color flow cytometry in artificially created cell mixtures. By selecting the CD45(+) population and simultaneous staining with several leukocyte lineage markers (CD3, CD4, CD8, CD56, and CD19), MHC-mismatched leukocytes were consistently detected in cell suspensions prepared from directly stained whole blood samples with a threshold sensitivity as low as 0.1%-0.2%. When the fresh peripheral blood mononuclear cells were separated by conventional Ficoll gradient purification, similar, but slightly lower levels of donor cells were detected. Blood samples obtained 1-5 months after liver, kidney, and intestine transplants revealed that the kind of organ allograft influenced levels and lineage pattern of the circulating donor cells. This procedure provided a simple and reliable method in determining early chimerism in transplant recipients. However, the detection of MHC-mismatched leukocytes of all lineages was much lower when frozen peripheral blood mononuclear cells were used. 相似文献
95.
Laperriere A Ironson GH Antoni MH Pomm H Jones D Ishii M Lydston D Lawrence P Grossman A Brondolo E Cassells A Tobin JN Schneiderman N Weiss SM 《Journal of health psychology》2005,10(2):223-231
This prospective multisite Phase III clinical trial (Miami, New York, New Jersey) investigated the long-term (one year) effects of a 10-week group cognitive-behavioral stress management/expressive supportive therapy (CBSM+) intervention on disadvantaged minority women living with AIDS. The CBSM+ intervention consisted of 10-weekly group session of stress management, cognitive-behavioral skill training, relaxation techniques and expressive-supportive therapeutic strategies. The primary study outcome was self-reported depression scores as measured by the BDI. The CBSM+ Group intervention significantly decreased depression scores on the BDI for women following the intervention and maintained the decreased level at one-year follow-up. 相似文献
96.
Dysfunction of axonemal dynein heavy chain Mdnah5 inhibits ependymal flow and reveals a novel mechanism for hydrocephalus formation 总被引:8,自引:0,他引:8
Ibañez-Tallon I Pagenstecher A Fliegauf M Olbrich H Kispert A Ketelsen UP North A Heintz N Omran H 《Human molecular genetics》2004,13(18):2133-2141
Motility of unicellular organisms occurred early in evolution with the emergence of cilia and flagella. In vertebrates, motile cilia are required for numerous functions such as clearance of the airways and determination of left-right body asymmetry. Ependymal cells lining the brain ventricles also carry motile cilia, but their biological function has remained obscure. Here, we show that ependymal cilia generate a laminar flow of cerebrospinal fluid through the cerebral aqueduct, which we term as 'ependymal flow'. The axonemal dynein heavy chain gene Mdnah5 is specifically expressed in ependymal cells, and is essential for ultrastructural and functional integrity of ependymal cilia. In Mdnah5-mutant mice, lack of ependymal flow causes closure of the aqueduct and subsequent formation of triventricular hydrocephalus during early postnatal brain development. The higher incidence of aqueduct stenosis and hydrocephalus formation in patients with ciliary defects proves the relevance of this novel mechanism in humans. 相似文献
97.
98.
Empiric analysis of the interactions involved in the formation of Fc receptor rosettes 总被引:1,自引:0,他引:1
R C Beckett A D Bankhurst D E Van Epps R C Williams 《International archives of allergy and applied immunology》1978,56(1):65-72
Erythrocytes coated with IgG were used in forming rosettes with lymphocytes and polymorphonuclear leukocytes to investigate Fc receptors. The density of the IgG-Fc coating on erythrocytes predictable influenced the number of rosettes formed with leukocytes. This relationship could be empirically described by application of the Hill equation derived from studies of molecular interactions in other biologic systems. The approximate Hill coefficient for Fc receptors was 2.4. These findings suggest at least two possible models for membrane Fc receptor function. 相似文献
99.
Liver function was assessed in 38 Edinburgh haemophiliacs. Results before the introduction of NHS intermediate factor VIII concentrate from 1974 onwards were compared with values in 1979. Measurements of serum bile salts in 16 patients as well as conventional liver function tests gave useful evidence of deranged liver function. Deterioration over the five-year follow-up period was seen only in patients on home treatment using large amounts of factor VIII concentrate, and there was no association between cryoprecipitate usage and derangement of liver function. 相似文献
100.
Sarah Curran Lindsey Kent Alison Gould Louise Huckett Sandra Richards Eric Taylor Philip Asherson 《American journal of medical genetics. Part A》2002,114(3):269-271
Several lines of evidence implicate synaptosomal‐associated protein of 25 kDa (SNAP‐25) in the etiology of attention deficit hyperactivity disorder (ADHD). Most notably, the coloboma mouse mutant, considered to be a good animal model of hyperactivity, has a deletion spanning this gene. Introducing a SNAP‐25 transgene into these animals alleviates hyperlocomotion. We have identified a novel microsatellite repeat in SNAP‐25 located between the 5′UTR and the first coding exon, and tested for association with ADHD. Case‐control analyses suggest there may be a role of this polymorphism in ADHD, with one allele over‐represented in controls and another over‐represented in probands. Within‐family tests of linkage and association confirmed these findings. Further work is needed to ascertain the role of SNAP‐25 in ADHD and assess the functional significance of this polymorphism. © 2002 Wiley‐Liss, Inc. 相似文献