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A modified protein-bound cobalamin absorption test was used to study dietary cobalamin absorption in healthy adults of different age groups and patients with isolated low serum concentrations of cobalamin. Dietary cobalamin absorption was significantly reduced in healthy adults aged 55-75 years compared with young adults, with a further reduction in those older than 75 years. No difference was detected between dietary cobalamin absorption in patients with isolated low serum cobalamin and controls of a similar age group. Cobalamin malabsorption was associated with elevated serum gastrin. The diagnostic value of this protein-bound cobalamin absorption test in the elderly was limited by the frequent finding of reduced absorption in healthy elderly people with normal serum cobalamin concentrations. The performance of such tests should be evaluated in different age groups before application in diagnosis.  相似文献   
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BACKGROUND: Seborrhoeic dermatitis (SD) is a common dermatosis in human immunodeficiency virus (HIV)-positive patients, many of whom do not respond satisfactorily to conventional topical treatments such as corticosteroids and antifungals. OBJECTIVE: A pilot study to investigate the efficacy and tolerability of pimecrolimus cream 1% in HIV-positive patients with facial SD. METHODS: In a single-centre study, 21 HIV-infected patients with mild to severe SD were treated twice daily with pimecrolimus cream 1% for 14 days. Thereafter, treatment was discontinued and patients followed up for 5 weeks. Skin involvement at baseline and on days 7, 14, 21, 35 and 49 was assessed using a four-point clinical score and digital photography. MAIN OUTCOME MEASURES: Efficacy and safety of pimecrolimus cream 1% treatment and incidence of relapse in the follow-up phase. Results Marked improvement was seen in clinical parameters at day 7, with >or= 90% patients clear of symptoms at day 14. Relapse was observed at day 35 but signs were milder than at baseline. All patients responded to therapy, despite their immunological status. Pimecrolimus did not alter CD4(+) and CD8(+) T-cell counts or viral load during the treatment period. CONCLUSION: Pimecrolimus cream represents a new, effective therapeutic option for facial SD in HIV patients.  相似文献   
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In-vitro maturation (IVM) of oocytes is a promising technique to reduce the costs and avert the side-effects of gonadotrophin stimulation for in-vitro fertilization (IVF). The pregnancy rates from oocytes matured in vitro are much lower than those of in-vivo stimulation cycles indicating that optimization of IVM remains a challenge. Therefore, we investigated the effect of supplementation of the medium with gonadotrophins, oestradiol and epidermal growth factor (EGF) and the effect of retaining or removing the cumulus cells on nuclear and cytoplasmic maturation of immature oocytes. Human germinal vesicle (GV) oocytes obtained after gonadotrophin stimulation for intracytoplasmic sperm injection (ICSI) were cultured in a complex defined medium either supplemented with gonadotrophins, oestradiol and physiological concentrations of EGF (2 ng/ml) or gonadotrophins and oestradiol alone. The cumulus cells were either removed or kept intact. In GV stage oocytes cultured without cumulus (group I) significantly more oocytes reached the metaphase II (MII) stage at 30 h in media supplemented with EGF (64.3 versus 33.9%, P < 0.003). For oocytes cultured with intact cumulus (group II), more oocytes reached MII at 30 h than in group I, but there was no difference in medium with or without EGF supplementation (81.8 and 79.8% respectively). Cytoplasmic maturation of MII oocytes was judged from their capability to activate and fertilize after ICSI. In group I, the rates of activation and normal fertilization were similar. However, in group II, significantly more oocytes underwent normal fertilization in the EGF-supplemented than the unsupplemented group (71.7 versus 45.6%, P < 0.05). The cleavage rates of the fertilized oocytes were similar in the sibling oocyte subgroups cultured with or without EGF supplementation, but the overall cleavage rates were higher in cumulus-intact compared to cumulus-denuded oocytes (88.9 versus 47.8%, P < 0.001). Thus, supplementation of the maturation medium with EGF and maintenance of the cumulus during culture improve the nuclear and cytoplasmic maturation of human oocytes in vitro.   相似文献   
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A formulation of 2% cromolyn sodium (CS) ophthalmic solution without the preservative, 2-phenylethanol, was compared with placebo in 58 patients with seasonal allergic conjunctivitis. Selection was based on history and positive skin tests. Neither immunotherapy nor use of antihistamines was allowed. This study was double-blinded and stratified by RAST scores to assure comparable groups. Either CS or placebo was used six times daily. Patients were observed weekly for 5 weeks during the peak of the fall weed-pollen exposure. Nasal symptoms were treated as required with beclomethasone nasal spray, and uncontrolled ocular symptoms were treated with boric acid and ephedrine solution. Nasal and ocular symptoms were recorded. There was a significant suppression of eye symptoms in the group receiving CS ophthalmic solution (p less than 0.02) during weeks 2, 4, and 5. There was a trend for nasal symptoms and the requirement for nasal beclomethasone to be less in patients receiving CS.  相似文献   
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In a human in-vitro fertilization (IVF) programme, the effect of co- culture of embryos with human fibroblasts was evaluated with respect to pregnancy rate and embryo development. Patients were included in the study after giving informed written consent. The IVF treatments were randomly assigned by stratification of both age (<36 versus > or =36 years) and previous IVF attempts (yes versus no). After fertilization was established, the zygotes were transferred to a 4-well dish with or without fibroblasts and cultured for 2 days. On the third day after ovum pick-up (OPU), cell number and quality [5 (good) to 1 (poor)] of the embryos were scored and a maximum of three embryos was transferred. Supernumerary embryos of good quality were cryopreserved. The design of this study was a group sequential trial with the objective of detecting differences between pregnancy rates following IVF with conventional incubation or incubation in co-culture with fibroblasts. This design included one evaluation at half-way data collection. In the study, 148 patients had an OPU, of whom 77 were allocated to the co-culture group. There was no statistically significant difference in pregnancy rate, cell number and embryo quality between the two groups. The ongoing pregnancy rate per embryo transfer was 27% in co-culture and 30% in the conventional culture group. The implantation rates per transferred embryo were 17 and 18% respectively. Using a multivariate logistic regression model for the probability of ongoing pregnancies, the odds ratio of co-culture, adjusted for age and previous IVF attempts, was not statistically significant. In conclusion, co-culture with human fibroblasts does not contribute to an improvement of embryo quality nor to a higher pregnancy rate after IVF in an unselected group of patients.   相似文献   
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The UTX gene escapes X inactivation in mice and humans   总被引:7,自引:3,他引:7  
We recently have identified a ubiquitously transcribed mouse Y chromosome gene, Uty , which encodes a tetratricopeptide repeat (TPR) protein. A peptide derived from the UTY protein confers H-Y antigenicity on male cells. Here we report the characterization of a widely transcribed X-linked homologue of Uty , called Utx , which maps to the proximal region of the mouse X chromosome and which detects a human X-linked homologue at Xp11.2. Given that Uty is ubiquitously transcribed, we assayed for Utx expression from the inactive X chromosome (Xi) in mice and found that Utx escapes X chromosome inactivation. Only Smcx and the pseudoautosomal Sts gene on the mouse X chromosome have been reported previously to escape inactivation. The human UTX gene was also found to be expressed from Xi. We discuss the significance of these data for our understanding of dosage compensation of X-Y homologous genes in humans and mice.   相似文献   
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