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1.
2.
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
3.
E. Svensjö K. E. Andersson E. Bouskela F. Z. G. A. Cyrino S. Lindgren 《Inflammation research》1993,39(1-2):35-41
Two inhibitors with selective effect on cyclic nucleotide phosphodiesterases (PDEs, preferentially hydrolyzing cAMP), milrinone (cGMP-inhibited PDE) and rolipram (cAMP-specific PDE) were studied for their effects on bradykinin-induced plasma leakage in comparison with the 2-receptor stimulant terbutaline. The dilation of arterioles induced by milrinone and rolipram was studied in the concentration range 10–7–10–4
M. Maximal arteriolar dilation was 53% for milrinone at 10–4
M and 28% for rolipram at 10–4
M. The hamster cheek pouch preparation was used as prepared for intravital microscopy of fluorescein-labelled dextran, FITC-dextran. Bradykinin was applied topically to the cheek pouch at a final concentration of 4×10–7
M and caused rapid and reversible increase in plasma leakage (number of leakage sites) from postcapillary venules. Milrinone (M), rolipram (R) and terbutaline (T) were also applied topically starting 5 min prior to bradykinin application and at final concentration of 10–4 and 10–5
M (M), 10–5 and 10–6
M (R) and 10–7
M (T). These local concentrations resulted in significant (p<0.05) and reversible inhibition of the bradykinin-induced response by 44% and 33% (M), 77% and 67% (R) and 46% (T). Combining M and R individually with T resulted in a significantly larger inhibition of the bradykinin response than with each of the drugs given separately.It is concluded that selective inhibitors of PDEs, preferentially hydrolyzing cAMP, can result in a reduced response to bradykinin as seen with 2-receptor agonists and that the potency of these two PDE inhibitors to counteract plasma leakage was not correlated to their potency as vasodilators. 相似文献
4.
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.
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
6.
7.
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
8.
The effects of sports participation on the development of left ventricular mass in adolescent boys 下载免费PDF全文
9.
Alcohol Consumption and Periodontitis: Quantification of Periodontal Pathogens and Cytokines 下载免费PDF全文
Eugênio J.P. Lages Fernando O. Costa Sheila C. Cortelli José R. Cortelli Luís O.M. Cota Renata Magalhães Cyrino Elizabeth M.B. Lages Gilson C. Nobre‐Franco João A.R. Brito Ricardo S. Gomez 《Journal of periodontology》2015,86(9):1058-1068
Background: There are few studies on periodontal status related to microbiologic and immunologic profiles among individuals not or occasionally using alcohol and those with alcohol dependence. The aim of this study is to determine the effect of alcohol consumption on the levels of subgingival periodontal pathogens and proinflammatory cytokines (interleukin [IL]‐1β and tumor necrosis factor [TNF]‐α) in the gingival fluid among individuals with and without periodontitis. Methods: This observational analytic study includes 88 volunteers allocated in four groups (n = 22): individuals with alcohol dependence and periodontitis (ADP), individuals with alcohol dependence and without periodontitis (ADNP), individuals not or occasionally using alcohol with periodontitis (NAP), and individuals not or occasionally using alcohol without periodontitis (NANP). Levels of Porphyromonas gingivalis, Aggregatibacter actinomycetemcomitans, Prevotella intermedia, Eikenella corrodens, and Fusobacterium nucleatum were determined by real‐time polymerase chain reaction on the basis of the subgingival biofilm, and IL‐1β and TNF‐α were quantified by enzyme‐linked immunosorbent assay in gingival fluid samples. Results: Individuals with alcohol dependence showed worse periodontal status and higher levels of P. intermedia, E. corrodens, F. nucleatum, and IL‐1β than non‐users. No significant correlations between TNF‐α and bacterial levels were observed. However, in the ADP group, higher levels of E. corrodens were correlated with higher levels of IL‐1β. Conclusion: A negative influence of alcohol consumption was observed on clinical and microbiologic periodontal parameters, as well as a slight influence on immunologic parameters, signaling the need for additional studies. 相似文献
10.