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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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Anne EG Lenferink Joanne Magoon Christiane Cantin Maureen D O'Connor-McCourt 《Breast cancer research : BCR》2004,6(5):R514
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5.
After reconstructive vascular operations the patients need dynamic control and non-invasive monitoring. The purpose of the study was to reveal the potential of duplex scanning (DS) in assessment of bypasses function and diagnosis of postoperative complications. 148 patients after aorto-femoral and femoro-popliteal bypass, including patients with late postoperative complications (shunt thrombosis, stenosis or spurious aneurysm of anastomosis) were examined. Energy colored DS was performed in scans "Toshiba" SSH-140 and "Acuson" Sequoia-512. In ultrasonic diagnosis the vascular graft was imaged as a tube structure with hyperechogenic walls and distinct pulse; it was easy to detect the material of vascular graft. In examination of distal anastomosis the initial portions of efferent arteries were usually imaged distinctly. In satisfactory distal vascular bed, the shunt's blood flow did not differ from normal blood flow. In patients with multifocal lesions the spectrum of shunt's blood flow was similar to main-changed blood flow. Substantial change of blood velocity was revealed in complications (aneurysm or stenosis of anastomosis). Spurious aneurysm was imaged as a hypoechogenic pulsating formation. Thrombotic masses in aneurysm's cavity were distinctly detected at DS, unlike at angiography. In case of anastomosis insufficiency, the suture's disrupted filaments and free branch's ends could be imaged. Stenosis of anastomosis was characterized by visible lumen's stenosis, local thickening and unevenness of wall, spectrum's change and blood velocity increase. In shunt's thrombosis the DS permitted to follow the thrombed graft's path, to reveal the cause of thrombosis and to detect the condition of outflow tract. The authors regard DS as a method of choice in dynamic control for state of bypasses and arteries in patients after reconstructive operations in lower extremities arteries. 相似文献
6.
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
7.
The purpose of the study was to determine surgical policy in atherosclerotic lesions of aorta and lower extremities arteries on the basis on non-invasive diagnostic methods--duplex scanning (DS) and computer tomographic angiography (CTA). From 1998 to 1999 47 patients were examined on this program (DS + CTA). At the first stage of the study, 17 patients underwent translumbal aorto-arteriography at the same time with DS and CTA. Analysis of the angiograms revealed that sensitivity of angiography for detection of lesions in aorto-iliac segment was 94%, in femoro-popliteal segment--78%. Diagnostic mistakes were associated with partial thrombosis of aneurysm's lumen, as a result of which the aorta looked non-dilated in angiograms. Femoral arteries contrasted unsatisfactory in 4 patients because of low collateral blood velocity distal to occlusion of iliac arteries. Initial segments of deep and superficial femoral arteries closed each other in angiograms on anterior-posterior projection, and it also led to low potential of angiography in assessment of femoral arteries state. Complex of non-invasive diagnostic methods (DS + CTA) allowed to correct diagnosis in each case. The methods complemented one another: CTA permitted to make three-dimensional reconstruction of vascular tree and to study its on various projections; DS--to study the vascular wall's state and hemodynamical parameters of blood flow. At the second stage of the study, high sensitivity of DS and CTA allowed to reject traditional angiography in preoperative period. Intraoperative findings confirmed the provisional diagnosis completely. 相似文献
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Male patients (n=42) with atherosclerosis obliterans and stage IIA-III ischemia of lower extremities combined with class II-III angina pectoris were divided into 2 groups. Patients of group 1 (n=21) were given simvastatin (10-20 mg/day), clopidogrel (75 mg/day) and trimetazidine (60 mg/day) for 6 months, those of group 2 - simvastatin and clopidogrel also for 6 months. Statistically significant decreases of frequency of attacks of angina, nitroglycerine consumption and increases of walking distance occurred only in group 1. 相似文献
10.
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