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OBJECTIVE--To compare the prevalence of antibody to and proviral DNA of the retrovirus HTLV-I in relatives of 11 British patients with tropical spastic paraparesis who had migrated from Jamaica before they developed symptoms, and to examine factors possibly related to transmission of HTLV-I. DESIGN--Migrant, family study. Antibody state was determined by several methods and confirmed by western blotting; the polymerase chain reaction was used to detect proviral DNA. SETTING--Britain and Jamaica. SUBJECTS--All available first degree relatives: those born and still resident in Jamaica (group 1); those born in Jamaica who migrated to Britain (group 2); and index patients'' children who were born and resident in Britain (group 3). All had been breast fed and none had had blood transfusions. RESULTS--Of the 66 living relatives, 60 were traced. Seroprevalence among those born in Jamaica (irrespective of current residence) was 22% (10/46; 95% confidence limits 9 to 34%) compared with zero among British born offspring (0/14) and was higher in group 2 at 33% (7/21; 12 to 55%) than in group 1 at 12% (3/25; 0 to 25%). (Patients in group 1 had the greatest mean age.) Proviral DNA was not detected in any subject negative for HTLV-I antibody, making prolonged viral incubation in those negative for the antibody unlikely. CONCLUSION--In this sample factors related to place of birth and early residence were more important in transmission of HTLV-I than maternal or age effects. In areas with a low to moderate prevalence policies of preventing mothers who are carriers of the virus from breast feeding would be premature.  相似文献   
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In vivo cellular tropism of human T-cell leukemia virus type 1.   总被引:37,自引:21,他引:16       下载免费PDF全文
To establish the phenotype of human T-cell leukemia virus type 1 (HTLV-1)-infected cells in peripheral blood, the polymerase chain reaction was used to detect and quantitate viral DNA in subpopulations of leukocytes obtained from patients with tropical spastic paraparesis and asymptomatic carriers. HTLV-1 could not be detected in peripheral blood mononuclear cells thoroughly depleted of T lymphocytes (E- CD3-), nor could it be detected in highly enriched populations of B lymphocytes (E- CD19+), monocytes (E- CD14+), or natural killer cells (E- CD16+). T lymphocytes were strongly positive for HTLV-1, and fractionation of this population revealed that 90 to 99% of the HTLV-1 DNA segregated with the CD4+ CD8- and CD45RO+ subsets. No difference between the cell type distribution of HTLV-1 in the asymptomatic carrier and the subjects with tropical spastic paraparesis was evident. Southern hybridization of genomic DNA prepared from the peripheral blood of HTLV-1 carriers indicated that up to 10% of circulating leukocytes may carry the HTLV-1 provirus.  相似文献   
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OBJECTIVE--To examine whether intrapartum care and delivery of low risk women in a midwife managed delivery unit differs from that in a consultant led labour ward. DESIGN--Pragmatic randomised controlled trial. Subjects were randomised in a 2:1 ratio between the midwives unit and the labour ward. SETTING--Aberdeen Maternity Hospital, Grampian. SUBJECTS--2844 low risk women, as defined by existing booking criteria for general practitioner units in Grampian. 1900 women were randomised to the midwives unit and 944 to the labour ward. MAIN OUTCOME MEASURES--Maternal and perinatal morbidity. RESULTS--Of the women randomised to the midwives unit, 647 (34%) were transferred to the labour ward antepartum, 303 (16%) were transferred intrapartum, and 80 (4%) were lost to follow up. 870 women (46%) were delivered in the midwives unit. Primigravid women (255/596, 43%) were significantly more likely to be transferred intrapartum than multi-gravid women (48/577, 8%). Significant differences between the midwives unit and labour ward were found in monitoring, fetal distress, analgesia, mobility, and use of episiotomy. There were no significant differences in mode of delivery or fetal outcome. CONCLUSIONS--Midwife managed intrapartum care for low risk women results in more mobility and less intervention with no increase in neonatal morbidity. However, the high rate of transfer shows that antenatal criteria are unable to determine who will remain at low risk throughout pregnancy and labour.  相似文献   
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Linkage studies with 17q and 18q markers in a breast/ovarian cancer family.   总被引:2,自引:1,他引:1  
Genes on chromosomes 17q and 18q have been shown to code for putative tumor suppressors. By a combination of allele-loss studies on sporadic ovarian carcinomas and linkage analysis on a breast/ovarian cancer family, we have investigated the involvement of such genes in these diseases. Allele loss occurred in sporadic tumors from both chromosome 17p, in 18/26 (69%) cases, and chromosome 17q, in 15/22 (68%) cases. In the three familial tumors studied, allele loss also occurred on chromosome 17 (in 2/3 cases for 17p markers and in 2/2 cases for a 17q allele). Allele loss on chromosome 18q, at the DCC (deleted in colorectal carcinomas) locus, was not as common (6/16 cases [38%]) in sporadic ovarian tumors but had occurred in all three familial tumors. The results of linkage analysis on the breast/ovarian cancer family suggested linkage between the disease locus and 17q markers, with a maximum lod score of 1.507 obtained with Mfd188 (D17S579) polymorphism at 5% recombination. The maximum lod score for DCC was 0.323 at 0.1% recombination. In this family our results are consistent with a predisposing gene for breast/ovarian cancer being located at chromosome 17q21.  相似文献   
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Conidia of Colletotrichum gloeosporioides germinated on green and ripe tomato fruit with intact epicuticular wax, and formed penetration pegs below melanized appressoria. If the delicate layer of epicuticular wax was distupted by abrasion or removed by solvents before inoculation, apparent increased diffusion of fruit substances into the inoculum stimulated fungal growth, hyphal anastomosis and the production of penetration pegs from hyaline appressoria. This was followed by cutlcle erosion centred on the penetration pegs in green fruit allowing sec-ondary growth of infection hyphae. Due to the development of cutinase resistance when the cuticle became yellow at ripening, no cuticle erosion occurred at penetrations on ripe fruit Since cuticle erosion followed penetration of the cutinase-susceptible cuticle and since penetration peg formation was not hindered by the cutinase cuticle, the process of primary penetration is regarded as mechanical.  相似文献   
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The effect of neurotensin on submaximally-stimulated hepatobiliary and pancreatic secretion was studied in 6 healthy subjects. An intravenous infusion of neurotensin 1.4 ± 0.3 pmol/kg/min, designed to reproduce plasma neurotensin immunoreactivity levels within the physiological range, produced a significant increase in pancreatic bicarbonate output. Plasma concentrations of pancreatic polypeptide rose by 83 ± 16 pmol/l and were associated with a small reduction in trypsin, but no significant change in bilirubin outputs.  相似文献   
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Because of the difficulties patients have in adhering to their drug regimens a trial was performed in which patients with essential hypertension were given, in random order and for four weeks each, three different doses of atenolol to be taken once daily. Atenolol effectively decreased lying and standing blood pressures, and there was no difference between the effects of the three doses. The simplicity of the regimen, as well as atenolol''s freedom from troublesome side effects, should be valuable in helping patients adhere to long-term treatment.  相似文献   
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