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61.
Apology     
W. Keith C. Morgan 《CMAJ》1988,138(8):681-682
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62.
We describe the postnatal ontogeny and localization of insulin-like growth factors I and II (IGF-I and -II) in the rat. We have used oligodeoxyribonucleotide probes for in situ hybridization (hybridization histochemistry) and for Northern blotting. IGF-II mRNA is strongly expressed in liver, skeletal muscle, perichondrium, leptomeninges and choroid plexus of the newborn. Demonstrable levels fall dramatically in the liver at 18-20 days postnatally but persist for longer periods in muscle and remain undiminished throughout life in the pia/choroid plexus, indicating that different control mechanisms operate in these tissues. IGF-I mRNA is predominantly found in the liver. Its level in this organ rises well before levels of IGF-II fall. This suggests that distinct factors govern the expression of IGF-I and -II genes.  相似文献   
63.
To establish the distribution of blood lipid concentrations and the prevalences of other risk factors for cardiovascular disease in Britain 12 092 men and women aged 25-59 in Glasgow, Leicester, London, and Oxford were studied. Subjects were selected by opportunistic case finding, in which patients consulting their general practitioner for any reason were offered a health check by appointment, or random selection from age-sex registers, in which an invitation for a health check was posted. The overall rate of response was 73%, being 91-94% by opportunistic case finding and 36-63% by random selection. At the health check subjects answered a brief questionnaire about risk factors for cardiovascular disease, and their height, weight, and blood pressure were recorded; a blood sample was taken for measuring plasma concentrations of cholesterol, triglyceride, high density lipoprotein cholesterol, and glucose.The mean cholesterol concentrations were 5·9 (SD 1·2) and 5·8 (1·2) mmol/l in men and women, respectively. In London the mean value was 5·5 (1·2) mmol/l for both men and women and was significantly lower than mean values in the three other centres, among which there were no significant differences. In men and women aged 25-29 concentrations were similar but they increased in men until the age of 45-49, after which they showed no further increase; in women concentrations did not increase until the age of 40-44 and by the age of 50-59 values were higher than in men. Mean triglyceride concentrations were significantly higher in men than in women (1·8 (1·4) v 1·3 (0·9) mmol/l, respectively), and trends with age were similar to those for cholesterol concentrations, except that at no age were values higher in women than in men. Mean triglyceride values overall were higher in Glasgow and London than in Oxford and Leicester. Body mass index was higher in Glasgow and London than in the other two centres and correlated with systolic and diastolic blood pressures and triglyceride concentration. In addition, subjects in Glasgow smoked significantly more than those in the other centres. These observations could contribute to the higher rate of coronary heart disease in Glasgow. Plasma lipid concentrations and the prevalences of other risk factors for cardiovascular disease were similar in subjects selected by opportunistic case finding and by random selection.In Britain cholesterol values have changed little during the past 12 years despite dietary recommendations and health education. Identifying subjects at particularly high risk of coronary heart disease is required to supplement advice to the general population to reduce the prevalence of this disease. Opportunistic case finding would be an appropriate method of identifying such subjects in general practice, although none of the potential markers for hyperlipidaemia was particularly useful in identifying all subjects at high risk.  相似文献   
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The mechanism responsible for the initial steps in the anaerobic degradation of trans-cinnamate and -phenylalkane carboxylates by the purple non-sulphur photosynthetic bacterium Rhodopseudomonas palustris was investigated. Phenylacetate did not support growth and there was a marked CO2 dependence for growth on acids with greater side-chain lengths. Here, CO2 was presumably acting as a redox sink for the disposal of excess reducing equivalents. Growth on benzoate did not require the addition of exogenous CO2. Aromatic acids with an odd number of side-chain carbon atoms (3-phenylpropionate, 5-phenylvalerate, 7-phenylheptanoate) gave greater apparent molar growth yields than those with an even number of side-chain carbon atoms (4-phenylbutyrate, 6-phenylhexanoate, 8-phenyloctanoate). HPLC analysis revealed that phenylacetate accumulated and persisted in the culture medium during growth on these latter compounds. Cinnamate and benzoate transiently accumulated in the culture medium during growth on 3-phenylpropionate, and benzoate alone accumulated transiently during the course of trans-cinnamate degradation. The transient accumulation of 4-phenyl-2-butenoic acid occurred during growth on 4-phenylbutyrate, and phenylacetate accumulated to a 1:1 molar stoichiometry with the initial 4-phenylbutyrate concentration. It is proposed that the initial steps in the anaerobic degradation of trans-cinnamate and the group of acids from 3-phenylpropionate to 8-phenyloctanoate involves -oxidation of the side-chain.Abbreviation 3-PP 3-phenylpropionic acid - 4-PB 4-phenylbutyric acid - 5-PV 5-phenylvaleric acid - 6-PH 6-phenylhexanoic acid - 7-PH 7-phenylheptanoic acid - 8-PO 8-phenyloctanoic acid - 4-P2B 4-phenyl-2-butenoic acid - GC/MS Gas chromatography/Mass spectrometry - HPLC High-pressure liquid chromatography  相似文献   
67.
Results indicate that recovery of embryos on Days 11 and 13 of pregnancy was reduced for Day 5 embryos transferred to recipients on Day 6 of their oestrous cycle and was greatly reduced when embryos were transferred to recipients on Day 7 of the cycle (P less than 0.01). Administration of oestradiol-17 beta on Day 11 of the recipient's cycle did not appear to affect embryo development on Day 13. Day 6 embryos transferred to recipients on Day 8 of the oestrous cycle deteriorated rapidly within 24 h of transfer; there was no recovery of embryos from the uterus after 36 h. Treatment of pregnant gilts with 1 mg oestradiol-17 beta (i.v.) on Day 10.5 resulted in total embryonic loss by Day 23, but pregnancy rates of gilts treated with oestradiol-17 beta on Day 12 were similar to those of vehicle-treated gilts (60.6 vs. 71.4%).  相似文献   
68.
We have isolated a stable, recombinant Marek's disease virus (MDV) containing the lacZ gene of Escherichia coli inserted into the unique short region of the genome. The nucleotide sequence of the insertion site indicates that it lies within a sequence homologous to the US2 gene of herpes simplex virus. Stable insertion of the lacZ gene into the MDV US2 gene indicates that the site is nonessential for MDV growth in cell culture.  相似文献   
69.
Six female and six male adult rhesus macaques were given sticks and nylon balls as an attempt at simple cage enrichment. A latin square design was used to compare behavior during separate 4-week periods with each object and during a control period with no object. Frequency and duration of 15 different behaviors were recorded. Resting was the most common activity which decreased slightly in duration when the stick or nylon ball was present (P less than 0.02). The mean duration of stick use was longer than that of the nylon ball (P less than 0.01). No other behaviors changed significantly, including the frequency of abnormal behaviors such as self-abuse, stereotypic acts, and bizarre postures. Generally, these objects were used infrequently and led to few changes in the behavior of singly-caged adult rhesus macaques. However, they did appear to stimulate activity for some individuals.  相似文献   
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