Dafydd Walters

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BACKGROUND The aim was to develop a standardised and externally paced field walking test, incorporating an incremental and progressive structure, to assess functional capacity in patients with chronic airways obstruction. METHODS The usefulness of two different shuttle walking test protocols was examined in two separate groups of patients. The initial 10(More)
Multiple pregnancies are relatively common after fertilization in vitro. Since two or more embryos are often replaced after in vitro fertilization, most twins are fraternal, but the incidence of identical twins also seems to be higher than the commonly accepted incidence after in vivo fertilization. This situation is of considerable biological interest,(More)
Nineteen European fertility centres participated in a controlled randomized trial aimed at comparing the effectiveness of five methods for the treatment of unexplained infertility. Each centre was invited to employ two of the five treatments being investigated, and the treatment allocated to individual patients was then decided by randomization. The(More)
The relation between ventilatory function and the reported frequency of consumption of fresh fruit and fruit juice was studied among 1502 lifelong non-smokers and 1357 current smokers aged 18-69 with no history of chronic respiratory disease. Forced expiratory volume in one second (FEV1) was assessed by turbine spirometry. As winter fruit consumption was(More)
An individual's responses to Goldberg's 30-item General Health Questionnaire are usually represented as a single score which provides a measure of the number of psychiatric symptoms reported. No account is taken of the nature of the symptoms. Factor analyses of the GHQ-30 were undertaken in ten randomly selected samples of 600 adults each, and also on 12(More)
Individual gonadotrophic hormones were used to examine the degree to which changes in intercellular coupling between somatic and germ cells initiate meiotic maturation, regulate protein synthesis or alter the ultrastructure of the ovine oocyte. Follicle Stimulating Hormone (FSH; 50 ng ml-1) suppressed intercellular coupling to the same extent as that(More)
Spermatozoa from patients who underwent in vitro fertilization (IVF) therapy were prepared free from seminal plasma with the use of IVF culture medium supplemented with 8% human serum. Samples were then stored either at room temperature or in a refrigerator, and their motility and ability to penetrate zona-free hamster eggs were assessed every second day.(More)
Ovulation induction alone, and ovulation induction in conjunction with one of four assisted procreation methods [intra-uterine insemination (IUI), intra-peritoneal insemination (IPI), gamete intra-Fallopian transfer (GIFT) or in-vitro fertilization (IVF)] were tested as a treatment for male infertility in a prospective randomized trial. The trial when(More)
The study reports the performance of four indirect enzyme-linked immunosorbent assays (ELISAs) for antibody (AB) detection using microtitre plates which were precoated with native or heat/detergent denatured antigens (AGs) from Trypanosoma congolense (T.c.) and T. vivax (T.v.), and stored for between 1 to 206 days at +37 degrees C. Bovine serum samples were(More)
Couples with male infertility (n = 86), idiopathic infertility (n = 68), and cervical mucus hostility (n = 48) of a long duration were treated either by in vitro fertilization (IVF) or artificial insemination with husband's semen (AIH). The incidence of pregnancy per cycle in couples in whom the male partner was infertile was significantly (P less than(More)