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11.
F G Araujo P M Coelho L H Pereira J Pellegrino 《Clinical and experimental immunology》1977,28(2):289-291
Skin-graft rejection in mice experimentally infected with Schistosoma mansoni is delayed when grafting is performed 60 days after the infection. In mice infected 30 days prior to the grafting, the grafts were rejected at the same time both in infected and in control animals. This observation indicates that impairment of cell-mediated immune response occurs in mice with mature S. mansoni infections. 相似文献
12.
Pato CN Macedo A Ambrosio A Vincent JB Bauer A Schindler K Xu J Coelho I Dourado A Valente J Azevedo MH Kennedy JL Pato MT 《American journal of medical genetics》2000,96(6):854-857
We have studied 24 families with multiple affected members with bipolar disorder to test the hypothesis that in those families clinically showing genetic anticipation [Macedo et al., 1999] we would find large repeat expansions. The families meeting inclusion criteria had a minimum of two affected members over two generations and showed marked anticipation both in terms of age of onset and disease severity. We used the repeat expansion detection (RED) method to test patients (n = 24) and controls from these families and unrelated controls (n = 53). We also genotyped patients and family members from two families with large expansions at the known expansion loci on chromosomes 13, 17, and 18. The RED method revealed a higher number of large expansions in patients compared with controls (t-test; P < 0.0055: Mann-Whitney U; P = 0.02). The patients with the largest expansions were typed at the specific loci on chromosomes 13, 17, and 18 and the chromosome 18 expansion locus segregated with disease in one family, and a second family showed segregation with the expansion located at the SCA8 locus on chromosome 13. Genetic anticipation had been analyzed in this cohort of families, with correction for potential ascertainment bias, possible proband effects, cohort effects, regression to the mean, gender effects, and maternal vs. paternal transmission. None of these potential confounds appeared to account for the observed anticipation. We also identified that the presence of large expansions in affected family members derives primarily from two families from the genetically isolated Azores population. One family shows segregation with the chromosome 18 locus, whereas the other family segregates with expansions at the SCA8 locus. Am. J. Med. Genet. (Neuropsychiatr. Genet.) 96:854-857, 2000. 相似文献
13.
14.
Outbreak of carbapenem-resistant Acinetobacter baumannii producing the OXA-23 enzyme in Curitiba,Brazil 总被引:19,自引:0,他引:19
Dalla-Costa LM Coelho JM Souza HA Castro ME Stier CJ Bragagnolo KL Rea-Neto A Penteado-Filho SR Livermore DM Woodford N 《Journal of clinical microbiology》2003,41(7):3403-3406
Carbapenem-resistant Acinetobacter baumannii isolates were obtained from eight patients in two hospitals in Curitiba, Brazil. The isolates were multiresistant, belonged to a single strain, and produced the OXA-23 carbapenemase. Treatment options were limited, although the isolates were susceptible to polymyxin B in vitro. The strain contributed to the deaths of five patients. 相似文献
15.
Isabel M. Coelho Maria Teresa Pereira G. Virella R. A. Thompson 《Clinical and experimental immunology》1974,17(4):685-689
The saliva of an individual with selective IgA deficiency was found to contain IgG and IgM, with some of the IgM linked to secretory component. Some specimens showed evidence of low molecular weight immunoglobulin fragments, presumed to be the result of proteolysis. 相似文献
16.
Well-characterised human osteoblastic bone marrow cell cultures are a useful in vitro tool to analyse bone tissue/biomaterials interactions. In this work, human bone marrow was cultured in experimental conditions described to favour osteoblastic differentiation and, serially passaged cells were cultured in two widely used culture media, minimum essential medium Eagle, alpha modification (alpha-MEM) and Dulbecco's modified Eagle's medium (DMEM). Cultures were grown for 35 d and compared concerning morphologic appearance on scanning electron microscopy (SEM), cell viability/proliferation, total protein content, activity of alkaline phosphatase (ALP) and ability to form calcium phosphate deposits. Results showed that cell proliferation was similar in cultures grown in the two media but ALP activity and ability to form mineralised deposits were lower in DMEM cultures. In both experimental situations, osteoblastic parameters were strongly reduced on cell passage, particularly from the first to the second subculture. In the experimental conditions used (presence of ascorbic acid, sodium beta-glycerophosphate and dexamethasone in the primary and secondary cultures), osteoblastic differentiation was observed in the first and second subcultures grown in alpha-MEM and in the first subculture grown in DMEM. These results underline the importance of the definition of the experimental conditions in studies involving bone cell cultures. 相似文献
17.
B. W. Jervis M. Coelho G. W. Morgan 《Medical & biological engineering & computing》1989,27(5):484-490
Work undertaken to investigate the effect on EEG responses of ocular artefact removal by proportional electro-oculogram subtraction
using the least-squares method is reported. The ocular artefact model and the least-squares approach to estimation of the
model parameters and hence of the EEG waveform, including the response, are described. Results are presented to show that
the response shapes become modified if ocular artefact removal is implemented recursively. This happens because the response
is incorrectly treated as part of the random background EEG. The solution is to incorporate a model of the response within
the ocular artefact removal algorithm. The results of tests on simulated data confirm these conclusions. The results of the
incorporation of response models in removing ocular artefacts from CNV recordings are presented. Even with modelling recursive
ocular artefact removal is found to modify the shape of the CNV, and so reliable results can only be obtained if the removal
is implemented nonrecursively. Evidence is given that it is advisable to remove DC levels from the recorded data. 相似文献
18.
19.
Battaglia C; Artini PG; Giulini S; Salvatori M; Maxia N; Petraglia F; Volpe A 《Human reproduction (Oxford, England)》1997,12(11):2477-2482
The objective of this study was to evaluate the Doppler flow variations
which occur following the use of different protocols of ovarian stimulation
in an IVF programme, and to investigate the thromboxane production by
cultured endometrial cells and its influence on embryo implantation. A
total of 60 patients underwent three different ovarian stimulation
protocols: long gonadotrophin-releasing hormone agonist (GnRH-a), short
GnRH-a and no GnRH-a. Transvaginal ultrasonography and colour Doppler
analysis were performed before and during the treatment. On the day that
the Doppler examination took place, luteinizing hormone, follicle
stimulating hormone, plasma oestradiol and thromboxane concentrations were
assayed. On the day of oocyte retrieval, endometrial cells were collected
and cultured, and their thromboxane production evaluated. No significant
differences in hormonal, ultrasonographic or Doppler parameters were
observed between the three groups. Ten out of 56 patients who had a
successful embryo transfer became pregnant. In the group of pregnant women
the pulsatility index values of both uterine and spiral arteries was lower
than in non-pregnant patients, and was associated with significantly lower
thromboxane concentrations from cultured endometrial cells. It is concluded
that thromboxane plays a role in embryo implantation, and that Doppler flow
analysis of uterine and spiral arteries in infertile patients may be
important in the management of ovarian stimulation.
相似文献
20.
A longitudinal study of maternal serum inhibin-A, inhibin-B, activin-A, activin-AB, pro-alphaC and follistatin during pregnancy 总被引:6,自引:1,他引:6
Fowler PA; Evans LW; Groome NP; Templeton A; Knight PG 《Human reproduction (Oxford, England)》1998,13(12):3530-3536
Maternal serum concentrations of inhibin-A, inhibin-B, activin-A,
activin-AB, pro-alphaC-related inhibin forms, total follistatin, steroids
and gonadotrophins were measured longitudinally in six normal singleton
pregnancies. Maternal venous blood was collected randomly during a
spontaneous follicular phase prior to donor insemination, at 5, 7, 9, 11,
16, 20, 24, 28, 32 and 36 weeks after the first missed menses and in the
early puerperium. Steroid and gonadotrophin profiles conformed to previous
reports. While at week 5 of gestation inhibin-A, activin-A and follistatin
concentrations were similar to those at the follicular phase, all three
increased progressively (P < 0.001) to maximal concentrations in week
36: approximately 48-fold (3740 +/- 1349 ng inhibin-A/ml), approximately
22-fold (6109 +/- 1443 ng activin-A/ml) and approximately 10-fold (3563 +/-
418 ng follistatin/ml) higher. Pro- alphaC concentrations reached a maximum
in weeks 5 (approximately 5- fold, P < 0.001) and 36 (1027 +/- 174
pg/ml, P < 0.01). Inhibin-B (71 +/- 23 pg/ml prior to pregnancy) was
undetectable (<12 pg/ml) between week 5-16 of gestation but increased
slightly in the third trimester (26 +/- 7 pg/ml in week 36). Activin-AB was
undetectable throughout pregnancy. Post-partum concentrations of inhibin-A
(41 +/- 12 ng/ml), inhibin-B (<12 pg/ml), activin-A (950 +/- 149 pg/ml),
pro-alphaC (128 +/- 22 pg/ml) and follistatin (990 +/- 79 ng/ml) were
substantially lower than at week 36 of gestation. The activin-A:follistatin
ratio increased from 0.5 in week 5 to 1.8 in week 36, suggesting that more
free activin-A is available in the maternal circulation during late
pregnancy.
相似文献