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111.
F W Johnson B A Matheson H Williams A G Laing V Jandial R Davidson-Lamb G J Halliday D Hobson S Y Wong K M Hadley et al. 《BMJ (Clinical research ed.)》1985,290(6468):592-594
A farmer''s wife who had helped with lambing aborted spontaneously in March after a short febrile illness in the 28th week of her pregnancy. She developed disseminated intravascular coagulation post partum with acute renal failure and pulmonary oedema. Recovery was complete after two weeks of hospital care. A strain of Chlamydia psittaci, probably of ovine origin, was isolated from the placenta and fetus. The patient''s serum showed rising titres of antibody against chlamydia group antigen; the placental and fetal isolates; and a known ovine abortion, but not a known avian, strain of C psittaci. IgG against both ovine abortion and enteric strains of C psittaci was detected, but IgM against only an abortion strain was detected. Histological examination showed pronounced intervillus placentitis with chlamydial inclusions in the trophoblast but no evidence of fetal infection or amnionitis. Laboratory evidence of chlamydial infection was found in an aborting ewe on the farm in January and in remaining sheep and lambs in July. Doctors should recognise the possible risk to pregnant women in rural areas where chlamydial infections in farm animals are widespread. 相似文献
112.
Mary Clare Walker Julia M. Phillips-Quagliata 《Cancer immunology, immunotherapy : CII》1985,20(1):47-54
Summary Patterns of genetic control of hybrid resistance to the BALB/c plasmacytoma LPC-1 were studied for comparison with those to MPC-11, a plasmacytoma investigated previously. The overall patterns of hybrid resistance to the two tumors were similar, i.e., hybrids between BALB/c and BALB congenic resistant (CR) strains, A and A CR strains, SJL and DBA/2 were as susceptible to LPC-1 as BALB/c mice themselves, whereas hybrids between BALB/c and AKR, C57BL/Ks, DBA/1, C57BL/6 (B6), C57BL/10 (B10) and B10 CR strains were resistant to LPC-1 as previously shown with MPC-11. Heterozygosity within the H-2 complex alone was insufficient for resistance to either tumor. Among hybrids between BALB/c and the B10 CR strains, however, the presence of certain H-2 haplotypes influenced the degree of resistance seen and this H-2 effect was different for the two tumors. A sex effect on resistance to LPC-1, but not to MPC-11, was seen among F1 hybrids between BALB/c and DBA/1 although not in any other F1 hybrids. Among ((B10×BALB/c)F1×BALB/c) and (BALB/c×(B10×BALB/c)F1) and ((BALB/c×B10)F1×BALB/c) and ((BALB/c×B10)F1×BALB/c) backcross mice, however, significantly more males than females were resistant to LPC-1 and the results of this study are compatible with the idea that in F1 hybrids between BALB/c and B10, resistance to LPC-1 is controlled by two dominant autosomal genes, one of which is sex-limited and neither of which is linked to H-2. In contrast, hybrid resistance to MPC-11 in this cross is controlled by a single gene. Cross-protection experiments indicated that the two tumors share at least one tumor-associated transplantation antigen. 相似文献
113.
Identification of a deletion in the low density lipoprotein (LDL) receptor gene in a patient with familial hypercholesterolaemia 总被引:5,自引:1,他引:4
B. Horsthemke Anna M. Kessling Mary Seed V. Wynn R. Williamson S.E. Humphries 《Human genetics》1985,71(1):75-78
Summary DNA samples from 60 unrelated UK patients with familial hypercholesterolaemia (FH) were screened by Southern blot hybridisation to detect gross alterations in the low density lipoprotein (LDL) receptor gene. One patient was found to have a 2kb deletion in the 3 part of the gene. The deletion cosegregates with the FH phenotype in his family. This finding is compatible with the deletion being the cause of FH in this case and makes a presymptomatic test based on DNA analysis available for this family. The defects in most of the other patients are likely to be due to point mutations. 相似文献
114.
Summary Expression of the anchorage-independent transformed phenotype in BHK 21/13 cells generally behaves as a recessive trait. When
chemically induced and spontaneously arising transformants are fused to the nontransformed parent line, transformation is
initially suppressed, reappearing after extended growth of the hybrids. In this paper, complementation for the expression
of anchorage independence was sought among a large group of such transformants, all independently derived from BHK 21/13 cells.
Tumorigenicity studies on selected hybrids and parental lines indicated that the in vitro trait of anchorage independence
is an accurate indicator of in vivo neoplasia for these cells. Seventeen of the 18 clones tested did not complement one or
more of three tester strains. This result indicates that anchorage independence arose in these clones as a result of lesions
in the same genetic function and suggests that the final step in the progressive changes of carcinogenesis may frequently
be restricted to lesions at a single locus.
This investigation was supported by National Institutes of Health grant CA27306. 相似文献
115.
The induction of congenital malformations among the offspring of male mice treated with X-rays at pre-meiotic and post-meiotic stages has been studied in two experiments. Firstly, animals were exposed to varying doses (108–504 cGy) of X-rays and mated at various time intervals (1–7, 8–14, 15–21 and 64–80 days post-irradiation), so as to sample spermatozoa, spermatids and spermatogonial stem cells. In the second experiment, only treated spermatogonial stem cells were sampled. One group of males was given a single 500-cGy dose, a second group a fractionated dose (500 + 500 cGy, 24 h apart) and a third group was left unexposed.In the first experiment, induced post-implantation dominant lethality increased with dose, and was highest in week 3, in line with the known greater radiosensitivity of the early spermatid stage. Preimplantation loss also increased with dose and was highest in week 3. There was no clear induction of either pre-implantation or post-implantation loss at spermatogonial stem cell stages.There was a clear induction of congenital malformations at post-meiotic stages, the overall incidence being 2.0 ± 0.32% in the irradiated series and 0.24 ± 0.17% among the controls. The induction was statistically significant at each dose. At the two highest doses the early spermatids (15–21 days) appeared more sensitive than spermatozoa, and at this stage the incidence of malformations increased with dose. The data from Expt. 1 on the induction of malformations by irradiation of spermatogonial stages were equivocal. In contrast, Expt. 2 showed a statistically significant induction of malformations at both dose levels (2.2 ± 0.46% after 500 cGy and 3.1 ± 0.57% after 500 + 500 cGy). The relative sensitivities of male stem cells, post-neiotic stages and mature oocytes to the induction of congenital malformations were reasonably similar to their sensitivities for specific-locus mutations, except that the expected enhancing effect of the fractionation regime used was not seen.Dwarfism and exencephaly were the two most commonly observed malformations in all series. 相似文献
116.
Summary In the montane herb Ipomopsis aggregata, size and placement of stamens and pistils vary substantially among flowers within plants, among nearby plants, and among groups of plants separated by 50–100 m. We trained captive hummingbirds to feed from flowers of this species in a flight cage, and explored the effects of different degrees of floral variability on carryover of fluorescent dyes that act as pollen mimics. We found that the slopes of linear dye carryover functions generally became more shallow as floral variability increased; this led to substantially longer carryover in the treatment with greatest variability. On the other hand, total amounts of dye transferred did not appear to be sensitive to the degree of variability. Floral variability may have a subtle but important effect on plant fitness by influencing the distance of pollen transfer. 相似文献
117.
Dennis Way Mary Hendrix Marlys Witte Charles Witte Ray Nagle John Davis 《In vitro cellular & developmental biology. Plant》1987,23(9):647-652
Summary An endothelial cell line derived from a massive recurrent chyle-containing retroperitoneal lymphangioma was isolated in monolayer
culture. Scanning and transmission electron microscopy and immunohistochemistry confirmed a close resemblance to blood vascular
endothelium with typical cobblestone morphology, positive immunofluorescence staining for endothelial marker Factor VIII-associated
antigen and fibronectin, and prominent Weibel-Palade bodies. The endothelial cells also exhibited other ultrastructural features
characteristic of lymphatic endothelium, including sparse microvillous surface projections, overlapping intercellular junctions,
and abundant intermediate filaments. This endothelial cell line represents a new source of proliferating lymphatic endothelium
for future study, including structural and functional comparison to blood vascular endothelium.
Supported in part by Arizona Disease Control Research Commission contracts 8277-000000-1-1-AT-6625 and ZB-7492. Presented
in part at the 10th International Congress of Lymphology in Adelaide, Australia, August 1985. 相似文献
118.
119.
The gene complex encoding the chain of the T-cell antigen receptor (Tcr) in man was previously reported to contain a restriction fragment length polymorphism (RFLP) involving a single Bgl II site adjacent to the second constant region gene. This RFLP allowed assignment of Tcr genotypes in certain human families. In the present study, two different RFLP in a V gene family were detected using the murine probe V8.1 in genomic DNA samples digested with the restriction endonucleases Hind III and Bam HI. Use of these RFLP to mark the V gene complex allowed complete haplotype assignment in four of seven families studied and provided support for linkage of the V gene complex to the constant region genes. Different combinations of the C and two V region markers can result in eight possible distinct haplotypes. The observation of all but one of the eight possible haplotypes in parents of the families studied suggests that recombination events occur between the C and V region and among members of the V region subfamily marked by the V8.1 probe. These markers can be used for mapping studies of the V gene complex in man and will allow an appraisal of possible associations between Tcr genes and disease susceptibility.Abbreviations used in this paper: Tcr
T-cell antigen receptor
- RFLP
restriction fragment length polymorphism
- C2
second Tcr constant region gene
- V
Variable
- C
constant
- J
joining
- D
diversity 相似文献
120.
We have studied the influence of DBA/2 non-H-2 antigens on the lethal graft-versus-host reaction (GVHR) developed across an H-2 barrier. (DBA/2 x B10.D2)F1 x B10.D2 (H-2
d) backcross (BC) mice were typed for their allelic constitution at nine genetically independent chromosome markers and used as individual cell donors simultaneously for two to three (DBA/2 X B10.D2)F1 recipients incompatible for DBA/2 non-H-2 antigens alone and two to three (DBA/2 x B10.BR)F1 recipients incompatible for DBA/2 non-H-2 antigens and H-2k. The results showed that, when compared with that developed in a control group incompatible for H-2
kalone [B10.D2(B10.D2xB10.BR)F1], the GVHR mortality seen in the presence of an additional incompatibility for DBA/2 non-H-2 antigens [(DBA/2 X B10.BR)F1recipients] is significantly delayed but only in female mice. An analysis of individual BC donors indicated that this protective effect of DBA/2 non-H-2 antigens correlates with incompatibility for gene(s) linked to the Pgm-1 chromosome marker. In contrast, incompatibility for gene(s) linked to Mod-1 and Es-3 markers accelerates GVHR mortality, but only in male mice. Finally, the results obtained with (DBA/2 x B10.D2)F1 and (DBA/2 x B10.BR)F1 recipients were compared; they showed that the intensity of the GVHR developed by cells from individual BC donors against a given set of DBA/2 non-H-2 antigens correlates well with that developed by the same BC donor against the same set of non-H-2 antigens plus H-2k. We conclude that certain non-H-2 genes (and antigens) can modulate the intensity of the GVHR developed across an H-2 barrier. The number of such genes is probably great; their effects are strong and complex, and can be sex-dependent. 相似文献