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This paper describes the tragic case of a young woman who died of cancer of the colon after successfully donating eggs to her younger sister. Although there is no direct link between her operation and the subsequent development of bowel carcinoma, this case imparts a feeling of unease when seen in conjunction with other cases reported during the last few years. It is a reminder that little is known of the long-term consequences of some aspects of assisted conception. Women undergoing ovarian stimulation for themselves or a matched recipient have the right to be advised, in an agreed format, that there is some concern about unproven potential risks from the stimulatory drugs. The safety of egg donors must assume priority over all other considerations, including lack of donors or any moral position. The recent decision by the Human Fertilisation and Embryology Authority (HFEA) to withdraw any form of payment or recompense to egg donors does not seem to us to be based on a balance of scientific advances, patient needs and the ethics of gamete supply. They state that the intention to withdraw payments was implicit in the 1990 Human Fertilisation and Embryology (HFE) Act. However the Act was based on the Warnock report made 6 years earlier. Even in 1990 ovum donation was uncommon and fertility drugs had not yet caused any unease. The Act provided the HFEA with discretionary powers to issue directions so that the future policies would be consistent with any emerging new medical evidence. It is imperative that the HFEA provide convincing evidence on how the current policy of payment to donors harms society, donors or recipients, and how in the UK the new policy will improve medical practice in assisted conception. Successful pilot studies must precede the implementation of any new policy. Failure to do this could cause irreversible harm to the practice of assisted conception using donor gametes, which will ultimately be against the basic aims of the 1990 HFE Act.   相似文献   
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The efficacy and safety of ciprofloxacin in the treatment ofPseudomonas aeruginosa infections was evaluated in 72 patients suffering from upper urinary tract infection (19 patients), deep soft tissue infection (16), chronic osteomyelitis (12), abscess (7), chronic otitis media (6), otitis externa (3) and bronchopneumonia (9). Forty-eight patients received an oral dose of 500 mg or 750 mg b.i.d. and five patients an i.v. dose of 200 mg b.i.d., while 19 patients were given both oral and parenteral doses. The duration of therapy ranged from seven days to more than four months. The MICs of ciprofloxacin for thePseudomonas aeruginosa strains isolated were in the range < 0.06–2 mg/l; 36% of the strains were resistant to all other available antibiotics. At follow-up after a minimum of six months the clinical success rate was 75% and the infecting organism was permanently eradicated in 49% of the patients. In nine patients the organism developed resistance, particularly when the initial MIC was higher than 0.5 mg/l. No significant adverse reactions were observed. Ciprofloxacin is the first antipseudomonal antimicrobial agent which can be administered orally and therefore fulfills a need in chemotherapy.  相似文献   
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Introduction  

This report describes the isolation and characterization of three new murine mammary epithelial cell lines derived from mammary tumors from MMTV (mouse mammary tumor virus)/activated Neu + TβRII-AS (transforming growth factor [TGF]-β type II receptor antisense RNA) bigenic mice (BRI-JM01 and BRI-JM05 cell lines) and MMTV/activated Neu transgenic mice (BRI-JM04 cell line).  相似文献   
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OBJECTIVE: To assess the antibody response to influenza vaccine of children vertically infected with HIV. DESIGN: Prospective study in HIV infected children vaccinated during the winter of 1994-5. SETTING: Family HIV clinic at St Mary's Hospital, Paddington. SUBJECTS: 25 children, aged 1-11 years, vertically infected with HIV. MAIN OUTCOME MEASURES: Responses to influenza antigens (H1N1-A/Taiwan/1/86, H3N2-A/Shandong/9/93, B/Panama/45/ 90) were tested by haemagglutination inhibition. Antibody responses were assessed according to clinical symptoms and immune function, stratified according to the 1994 revised classification for HIV infection in children. RESULTS: 23 children (92%) had either very low or no detectable antibody before vaccination. New protective antibody responses were made by 10 children (40%): in seven to a single antigen, in two to two antigens, and in one to all three antigens. For each antigen there was an overall small increase in the mean geometric titre of antibody produced, but this only reached a protective level for antigen H1N1 and for children with minimal symptoms. Less symptomatic children were significantly more likely to produce a protective antibody response to influenza vaccination. No association was found between immune function, as measured by CD4 count, and vaccine response. CONCLUSIONS: Only vaccination of the least symptomatic HIV infected children against influenza is likely to be effective. This will not only protect them against influenza, but will also protect other more immunosuppressed and vulnerable members of their families.  相似文献   
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Leukocyte integrin expression in patients undergoing cardiopulmonary bypass   总被引:3,自引:0,他引:3  
BACKGROUND: The recruitment of leukocytes to vascular endothelium is controlled by adhesion events mediated through the beta2 integrins, whereas the response of extravasated leukocytes within the tissues is controlled through the beta1 integrins. Although cardiopulmonary bypass (CPB) has been shown to be associated with a systemic inflammatory response and elevated levels of beta2 integrins on leukocytes, its effect on the beta1 integrins is not known. This study investigated the effect of the protease inhibitor aprotinin on the expression of the beta1 and beta2 integrins on circulating leukocytes in patients undergoing CPB. METHODS: Patients undergoing primary elective coronary artery bypass grafting were randomized into full-dose aprotinin or placebo groups. Blood samples were obtained at nine time points preoperatively, intraoperatively, and up to 6 days postoperatively. The surface expression of the beta1 integrins VLA-1, -3, -4, -5, and -6 and of the beta2 integrins CD11a/CD18, CD11b/CD18, and CD11c/CD18 was measured by flow cytometry on gated neutrophil and monocyte subpopulations in whole blood. RESULTS: Expression of the beta1 integrins was not significantly altered during the study period and, therefore, aprotinin had no effect on the expression of these molecules. Of the beta2 integrins, CD11b/CD18 expression was significantly increased on neutrophils at 15 minutes after onset of CPB in the placebo group (p < 0.01) but not in the aprotinin group. CONCLUSIONS: This study showed that expression of the beta1 integrins on neutrophils and monocytes did not alter during the first 6 days after CPB. Expression of the beta2 integrin CD11b/CD18 increased significantly on neutrophils during CPB in control patients but not in patients treated with full-dose aprotinin.  相似文献   
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Horne  MK d; Rosse  WF; Flickinger  EG; Saltzman  HA 《Blood》1975,45(3):365-375
The "early-labeled" peak (ELP) of 14CO excretion following injection of glycine-2-14C was used to study erythropoiesis in a patient with sideroblastic anemia and in four subjects with myeloproliferative disorders. The ELP was greatly enlarged in all patients, as compared with a normal volunteer. The contour of the peaks from the hematologically abnormal subjects suggested the presence of increased erythroid heme degradation. In the patient with sideroblastic anemia, all hours of the early peak were significantly reduced after transfusion. This was interpreted to mean that even the earliest or "nonerythroid" phase of the peak is influenced by erythropoietic activity, at least under conditions of erythropoietic stress.  相似文献   
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Next-generation mate-pair sequencing (MPS) has revealed that many constitutional complex chromosomal rearrangements (CCRs) are associated with local shattering of chromosomal regions (chromothripsis). Although MPS promises to identify the molecular basis of the abnormal phenotypes associated with many CCRs, none of the reported mate-pair sequenced complex rearrangements have been simultaneously studied with state-of-the art molecular cytogenetic techniques. Here, we studied chromothripsis-associated CCR involving chromosomes 2, 5 and 7, associated with global developmental and psychomotor delay and severe speech disorder. We identified three truncated genes: CDH12, DGKB and FOXP2, confirming the role of FOXP2 in severe speech disorder, and suggestive roles of CDH12 and/or DGKB for the global developmental and psychomotor delay. Our study confirmes the power of MPS for detecting breakpoints and truncated genes at near nucleotide resolution in chromothripsis. However, only by combining MPS data with conventional G-banding and extensive fluorescence in situ hybridizations could we delineate the precise structure of the derivative chromosomes.  相似文献   
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