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The mitochondrial genome of the selfed progeny of a plant regenerated from long-term somatic tissue culture displays specific structural rearrangements characterized by the appearance of novel restriction fragments. A mitochondrial DNA library was constructed from this selfed progeny in the SalI site of cosmid pHC79 and the novel fragments were subsequently studied. They were shown to arise from reciprocal recombination events involving DNA sequences present in the parental plant. The regions of recombination were sequenced and the nucleotide sequences were aligned with those of the presumptive parental fragments. We characterized an imperfect short repeated DNA sequence, 242 bp long, within which a 7-bb DNA repeat could act as a region of recombination. The use of PCR technology allowed us to show that these fragments were present in both parental plants and tissue cultures as low-abundance sequence arrangements.  相似文献   
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Two cases of accidental hanging that occurred at school in comparable circumstances in two three-year-olds are reported. The opposite outcomes in these two cases together with data from a review of the literature highlight the importance of first aid training to give victims of such injuries the best chance of survival.  相似文献   
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An immunotoxin containing the B-B10 MoAb, directed against the CD25 determinant, and the ribosome-inactivating protein saporin, inhibits 3H-TdR incorporation in phytohemagglutin, allogeneic-stimulated lymphocytes (primary and secondary mixed-lymphocyte reaction), and in an alloreactive T cell clone. A lower degree of inhibition was obtained with the B-B10 MoAb, which is known to inhibit IL-2 activity, as well as with the unconjugated compounds. These results suggest that the in vivo administration of the conjugate might be a more effective tool in the treatment of patients affected by graft-versus-host disease than B-B10 alone, by inducing an efficient killing of allogeneic-reacting T lymphocytes.  相似文献   
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AIM: To evaluate if intensive insulin regimen with multiple daily injections (MDI) is successful for treating type 1 diabetes patients over a long period of time in a regular clinical setting. METHOD: This is a prospective, observational seven-year study. Fifty-nine (35 male) type 1 diabetic patients with bad metabolic control (HbA1c> or =9%), aged 31.9 years, range 18-47 were included in the present study. All of them had had at least 5 years of diabetes duration after diagnosis and showed negative responses of serum C-peptide to a standard breakfast. The main control variables are: Metabolic control measured by serum HbA1c values (values < 6.2 % was the treatment objective) and the frequency of hypoglycaemic episodes (episodes/patient-month). RESULTS: Significant decreases in mean+/-SD HbA1c values in this group of patients were observed from the first year of follow-up, with the mean values being: 7.5+/-1.5%, 7.2+/-1.8%, 7.6+/-1.6%, 7.1+/-1.7%, 7+/-1.4, 6.6+/-1.6% and 6.8+/-1.4% for the first, second, third, fourth, fifth, sixth and seventh years of follow-up respectively. Sixteen %, 27.5%, 15.7%, 33.3%, 28.6%, 42% and 33% of the patients reached the treatment objective (HbA1c values<6.2%) for each year of follow-up. Throughout the study period the rate of severe hypoglycaemia (episodes/patient-year) was 0.32+/-0.2 which was not significantly different compared with the value of 0.28+/-0.1 observed the year before the study began. Similarly frequencies of mild/moderate hypoglycaemia episodes (episodes/patient-month) varies between 16.5+/-4 and 21.7+/-5, which are not significantly different from the value of 17.7+/-6 observed the year before the study began. CONCLUSION: Long-term improvement in metabolic control was observed in this group of type 1 diabetes patients with previous bad control, during treatment in a regular clinical setting. A considerable percentage of type 1 diabetic patients with MDI reached the treatment objective in every year of follow-up. Furthermore improvement in metabolic control is not associated with significantly increased frequency of hypoglycaemia episodes.  相似文献   
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OBJECTIVE: To study the feelings of HIV infected mothers during the perinatal period regarding circumstances of HIV diagnosis, disclosure to partner and fear of contamination. POPULATION AND METHODS: A study based upon personal interviews was carried out from November 2003 to January 2004 upon routine pediatric outpatient visits for infants born to HIV positive mothers. RESULTS: This study included 54 women of which 70% were from Sub-Saharan Africa. Fifty-nine per cent discovered their HIV status during a pregnancy. Seventy-seven per cent of partners were informed of maternal status. Among the women reluctant to inform their partner, the main reasons given were fear of violence and separation. Seventy-two per cent of interviewed women refused their spouses to be informed by the medical staff. Medical care during pregnancy (moral support, delivery) was judged as good by a majority of women (90%) who found the behavior of the staff mostly satisfactory. Final child serology remains the most definitive test for mothers, 47% of whom fear the risk of a potential postnatal contamination of their children. CONCLUSION: In these isolated women, many of whom have recently discovered their HIV status, a multidisciplinary approach including psychosocial support is essential.  相似文献   
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BACKGROUND AND OBJECTIVES: The aim of this study was to compare in a prospective nonrandomized study, the efficacy of 2 methods of administering methotrexate (MTX) in the treatment of ectopic pregnancy (EP): transvaginal injection under sonographic control or intramuscular injection (IM). METHODS: Patients with EP who met specific inclusion criteria for medical treatment were treated with MTX: 63 patients (group 1) were treated by IM and 47 patients (group 2) by transvaginal local injection. In group 1, 50 mg/m2 of MTX was injected intramuscularly; in group 2, transvaginal injection of 1 mg/kg of MTX was injected into the ectopic sac under sonographic control. When an additional dose of MTX was required, it was administrated IM at the dosage of 50 mg/m2 in both groups. RESULTS: The overall success rate, defined by a posttreatment normal hCG level (< 10 mUI/mL) was 71.4% in group 1 versus 91.5% in group 2 (P < 0.01); for patients with hCG levels < 2000 mUI/mL, 83% and 96%, respectively (not significant); for patients with hCG > or = 2000 mUI/mL, 37.5% and 86.4%, respectively (P < 0.01). CONCLUSION: In the medical treatment of EP, the efficacy of MTX is greater when administered by local transvaginal injection than by IM injection. We propose local treatment every time EP can be punctured, especially when hCG levels are > or = 2000 mUI/mL.  相似文献   
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OBJECTIVES: To examine factors influencing the rate of transmitted drug resistance (TDR) among seroconverters, with particular emphasis on 3 widely used genotypic drug resistance algorithms. METHODS: The study used data from CASCADE (Concerted Action on Seroconversion to AIDS and Death in Europe), a collaboration of seroconverter cohorts in Europe and Canada. Genotypic resistance data were derived within 18 months of the last seronegative test or date of laboratory evidence of acute infection and before the initiation of antiretroviral therapy. The Stanford algorithm was used to analyze each individual's nucleotide sequence. A multivariate logistic model was used to assess independent relationships between the presence of TDR and exposure category, sex, age at seroconversion, and year of seroconversion. The paper also describes 3 alternative definitions of resistance: the Stanford algorithm, the key resistance mutations defined by the International AIDS Society, and the Agence Nationale de Recherches sur le Sida (ANRS) algorithm. RESULTS: Forty-five of 438 patients (10.3%) seroconverting between 1987 and 2003 were infected with a drug-resistant HIV-1 variant. Forty patients (9.1%) showed resistance mutations to only 1 class of antiretroviral drugs, 2 (0.5%) to 2 classes, and 3 (0.7%) to 3 classes of antiretroviral therapy. It was suggested that individuals seroconverting later in calendar time were more likely to have TDR (relative risk 3.89 and 95% CI: 0.84 to 18.02, and relative risk 4.69 and 95% CI: 1.03 to 21.31, for 1996-1999 and 2000-2003, respectively, compared with pre-1996; P trend = 0.08). This trend was apparent regardless of the definition of TDR used. The total estimated proportion of individuals with TDR varied between 10.3% and 15.5% according to which definition was used. CONCLUSIONS: Evidence was found for the rise of TDR over time. A specific definition of what constitutes TDR rather than a simple list of mutations is needed.  相似文献   
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