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81.
Extraction and isoenzyme analysis of four isolates of Arthrobotrys including A. musiformis, A. robusta and A. conoides were conducted. Among the 14 enzymes studied by starch gel electrophoresis, using morpholine-citrate as gel/electrode buffer, the following nine enzymes showed interpretable banding patterns: alpha-esterase, fumarase, hexokinase, isocitrate dehydrogenase, leucine aminopeptidase, malate dehydrogenase, 6-phosphogluconate dehydrogenase, phosphoglucomutase and phosphoglucoisomerase. All isolates studied displayed typical isoenzyme phenotypes for each species. Two isolates of A. conoides differed in their alpha-isoesterase banding patterns, but no differences were observed for the other enzymes. The assay was satisfactory for enzyme extraction and resolution of Arthrobotrys and could be used in future taxonomic and genetic studies of this organism.  相似文献   
82.
The human mineralocorticoid receptor (MR) is a member of the steroid-thyroid hormone receptor superfamily, which includes receptors for retinoic acid, vitamin D, and other steroids, such as the glucocorticoids (which bind the glucocorticoid receptor, GR). MR and GR, the corticosteroid receptors, share significant homology and are activated by steroid binding, resulting in a conformational change, nuclear translocation, and DNA binding. Despite these similarities with GR, the MR remains less well characterized. However, protein components known to be present in the unliganded GR are also likely to be components of the heteromeric MR complex. In the current study, we investigated whether or not hsp70, hsp90, and the immunophilin FKBP-52 are present in the nonsteroid-bound MR complex, because these proteins are known to be present in the unliganded GR complex. The unliganded MR complex was assembled in vitro using reticulocyte lysate and in vivo using the baculovirus overexpression system and Spodoptera frugiperda (Sf9) cells. Western blot analysis revealed the presence of hsp70, hsp90, and FKBP-52 in the unliganded complexes, but hsp90 and FKBP-52 were not detected following exposure to aldosterone. Electrophoretic mobility shift analysis demonstrated that DNA binding of MR occurred only after treatment with aldosterone. These studies indicate that proteins associated with the unliganded GR are also present in the unliganded MR complex, and that hsp90 and FKBP-52 dissociate prior to DNA binding in a manner similar to that described for GR. Finally, the stoichiometric analysis of the proteins present within the heteromeric MR complex suggests a divergence between this receptor and the GR.  相似文献   
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The peritoneal environment in endometriosis is known to have growth-promoting effects on endometrial cells. To investigate whether follicular fluid, a contributor to the peritoneal fluid, stimulates endometrial cell proliferation, we incubated endometrial stromal cells in culture with various dilutions of follicular fluid obtained from women with or without endometriosis undergoing oocyte retrieval for in-vitro fertilization. Cell proliferation assays were performed using follicular fluid from 28 women (without endometriosis, n = 13; with endometriosis, n = 15) in eight different endometrial stromal cell culture set-ups. Cell proliferation was assessed by a colorimetric method. Maximum cell proliferation was detected when endometrial cells were incubated with 50% dilution of follicular fluid for 48 h. Follicular fluid from women with endometriosis induced significantly higher cell proliferation than follicular fluid from women without endometriosis (P < 0.05). Our findings indicate that follicular fluid contents may contribute to the growth-promoting factors in the peritoneal fluid of women with endometriosis.  相似文献   
85.
BACKGROUND: Large international variations in rates of prostate cancer incidence and mortality suggest that environmental factors have a strong influence on the development of this disease. The purpose of this study was to identify predictive variables for prostate cancer mortality in data from 59 countries. METHODS: Data on prostate cancer mortality, food consumption, tobacco use, socioeconomic factors, reproductive factors, and health indicators were obtained from United Nations sources. Linear regression models were fit to these data. The influence of each variable fit in the regression models was assessed by multiplying the regression coefficient b by the 75th (X75) and 25th (X25) percentile values of the variable. The difference, bX75 - bX25, is the estimated effect of the variable across its interquartile range on mortality rates measured as deaths per 100000 males aged 45-74 years. Reported P values are two-sided. RESULTS: Prostate cancer mortality was inversely associated with estimated consumption of cereals (bX75 - bX25 = -7.31 deaths; P = .001), nuts and oilseeds (bX75 - bX25 = -1.72 deaths; P = .003), and fish (bX75 - bX25 = -1.47 deaths; P = .001). In the 42 countries for which we had appropriate data, soy products were found to be significantly protective (P = .0001), with an effect size per kilocalorie at least four times as large as that of any other dietary factor. Besides variables related to diet, we observed an association between prostate cancer mortality rates and a composite of other health-related, sanitation, and economic variables (P = .003). CONCLUSIONS: The specific food-related results from this study are consistent with previous information and support the current dietary guidelines and hypothesis that grains, cereals, and nuts are protective against prostate cancer. The findings also provide a rationale for future study of soy products in prostate cancer prevention trials.  相似文献   
86.
Given the substantial increase in the numbers of community psychiatric nurses (CPNs) in England in the last 15 years this paper asks the question: is CPN activity where it should be? In-other words is activity distributed around the country according to need? Various indicators of need are suggested including population age structure, deprivation indices and suicide rates. We find no evidence -- based on information from scatterplots, Spearman correlations and more innovative measures of inequality -- that CPNs are distributed according to need. If this is confirmed by further research it is cause for alarm -- CPNs should be where they are most needed.  相似文献   
87.
Non-accidental head injury, be it shaking, impact(s) or a combination of the two, is characterised by subdural and/or subarachnoid haemorrhages with retinal haemorrhages, but minimal or absent external cranio-facial trauma. The classical assault scenario depicts the infant being gripped around the head, face, chest and abdomen and shaken or being gripped by a limb and swung. This gripping might be expected to leave physical evidence in the form of bruising. A study was undertaken to establish the prevalence, distribution and pathological association of external bruising in 24 cases of fatal non-accidental head injury in children. At autopsy, 17 cases had new external bruises, 15 old external bruises and 13, a combination of both. However, seven (29%) cases showed no fresh external bruising and five (21%) showed no external bruising at all. Thus, external bruising may be absent in children with fatal intracranial injury. The face was shown to be the commonest site of bruising followed by the forehead and buttocks. Limb, chest and abdominal bruising were found to be uncommon. Retinal haemorrhages were confirmed in 23 (96%) cases. It is hypothesised that bruising, when present, may be a result of abuse in the form of punches and slaps rather than due to gripping during the assault. We discuss why gripping does not necessarily result in external bruising.  相似文献   
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Errors made during the sample preparative process contribute significantly to the total analytical error of immunoassays. Reduction in the magnitude of these errors have been made by improvements in the manualfluid handling systems and mechanization of the individual steps in the process. The mechanization has been stimulated by developments in both computing hardware and software. A laboratory''s workflow and workload will indicate the degree of mechanization required.  相似文献   
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