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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   
4.

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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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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To investigate the involvement of epidermal growth factor (EGF) and its receptor in the pathogenesis of human pituitary adenomas, we examined the presence of EGF-binding sites in normal rat and human pituitaries and in human PRL- and GH-secreting and nonsecreting pituitary adenomas. Using crude membrane preparations, specific binding for [125I] EGF was found in normal rat and human pituitaries. Equilibrium was reached at 25 C in 40 min. There was no change in the Kd values between male rats [Kd, 0.65 +/- 0.35 nM (mean +/- SD)] and female rats (Kd, 0.51 +/- 0.15 nM), while the maximum capacity was significantly higher (P less than 0.05) in male rats (21 +/- 8 fmol/mg protein) than in female rats (10 +/- 2 fmol/mg protein). Scatchard analysis of the data suggested the presence of a single class of binding sites. In the three normal human pituitaries tested, specific [125I]EGF binding was also demonstrated. However, both the Kd and the maximum capacity varied widely. Twenty-two human pituitary adenomas were tested, but no specific binding was detected in any of them. In addition to the binding experiments, a radioreceptor assay using rat liver membranes was developed to detect EGF or EGF-like material in extracts of six human pituitary adenomas (two of each type). No EGF activity was detected in any of the extracts. From these results, we conclude that EGF-binding sites are present in normal pituitary tissue, suggesting a physiological role for EGF in this tissue. Consequently, the reason(s) for the lack of EGF binding in pituitary adenoma membranes is not known.  相似文献   
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Thirty late-onset adrenal hyperplasia patients consulting for isolated hirsutism were randomly divided into two groups; group 1 (n = 16) was treated with hydrocortisone in order to suppress androgen adrenal secretion, and group 2 (n = 14) received cyproterone acetate (CPA) antiandrogen therapy to inhibit peripheral androgen activity. The clinical and hormonal effects of each type of treatment were evaluated. Before treatment, the clinical and hormonal profiles of the two patient groups did not differ significantly. Excellent clinical evolution in terms of the regression of hirsutism was observed in the CPA-treated patients (54% decrease in the clinical score in 1 yr), in contrast with the slight decrease in hirsutism (26%) after hydrocortisone treatment. In hydrocortisone-treated patients, plasma androgen decreased to normal levels: testosterone from 3.05 +/- 1.45 to 1.46 +/- 0.42 nmol/L and delta 4-androstenedione from 13.6 +/- 4.1 to 6.33 +/- 1.47 nmol/L. Conversely, in CPA-treated patients, only a slight decrease in testosterone from 2.98 +/- 1.98 to 2.29 +/- 0.64 nmol/L and in delta 4-androstenedione from 12.9 +/- 5.9 to 9.86 +/- 2.23 nmol/L was observed. This slight decrease in plasma androgens contrasts with the rapid clinical improvement after CPA. These results emphasize the importance of peripheral receptivity to androgens in the clinical expression of hyperandrogenism. Moreover, they indicate that peripheral antiandrogen therapy may be more appropriate in late-onset adrenal hyperplasia patients than conventional adrenal inhibition using cortisone therapy.  相似文献   
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Objectives

Attention deficit hyperactivity disorder (ADHD) is a childhood neurological disorder. Studies have shown that children with ADHD are more prone to caries than those without. The study investigated children diagnosed with ADHD, both with and without pharmacological intervention, and the following: DMFT\dmft, plaque index (PI), mutans streptococci (MS) levels, lactobacilli (LB) levels, salivary flow, salivary buffer capacity, oral hygiene, and diet.

Study design

DMFT/dmft index, PI, MS and LB levels, salivary flow, and salivary buffer capacity were examined in three groups of children: ADHD1—diagnosed with ADHD with no pharmacological intervention (N?=?31), ADHD2—treated with medications for ADHD (N?=?30), and a healthy control group (N?=?30). Diet and oral health habits were assessed through questionnaires completed by parents.

Results

There were no differences in the DMFT/dmft index, MS and LB counts, salivary buffer capacity, and parent reported diet and oral health behavior between the three groups. Children with ADHD demonstrated a higher plaque index.

Conclusions

Although children with ADHD did not report different diet and oral health behavior from children without ADHD, this group had significantly higher levels of plaque than the control group, which combined with hyposalivation may be a risk factor for caries at an older age.

Clinical relevance

Medicated and non-medicated ADHD children were similar to control children in their caries rate, MS and LB counts, salivary buffer capacity, and diet and oral health behavior. They differed in the amount of plaque found on their teeth. As a group, ADHD children demonstrated hyposalivation compared with the control.  相似文献   
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