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991.
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OBJECTIVES: We describe the attitude and views of general practitioners towards the menopause and hormone replacement therapy (HRT) in metropolitan Brisbane, Australia. METHODS: A total of 216 general practitioners were nominated by a random sample of urband-welling women aged 45-54 years who formed the Brisbane Women's health study. A 20-30 minute face-to-face questionnaire with the general practitioners was administered and analysed by demographic characteristics. RESULTS: There was a 93% response rate. Management of the menopause and HRT was routinely undertaken by general practitioners for their own patients. After deciding to initiate HRT, > 60% of general practitioners ordered five investigations or more. They may have confused the risk of thrombo-embolism from oestrogens used in the post-menopause with that for contraception. There were differences between male and female practitioners in some areas. Male general practitioners, in particular, reported more difficulty with tailoring and adjusting regimes. CONCLUSIONS: Specific areas for further education are explored to meet the educational needs of general practitioners.  相似文献   
994.
995.
We previously detected elevated transforming growth factor beta-1 (TGF-beta1) serum levels in patients with invasive bladder carcinomas. In this study, we therefore investigated whether elevated serum levels correlate with enhanced TGF-beta expression in human bladder tumours. mRNA levels of TGF-beta1, -beta2 and -beta3 were reduced in bladder tumour tissue to 86%, 68% and 56%, respectively, of the levels in normal urothelium. On the other hand, TGF-beta1 protein levels were found to be higher in superficial tumours (Ta-T1) (mean level of 0.153 ng mg(-1)) and in invasive T2/T3 tumours (mean level of 0.104 ng mg(-1)) compared with normal urothelium (mean level of 0.065 ng mg(-1)). Invasive T4 tumours, however, contained only low amounts of TGF-beta1 (mean level of 0.02 ng mg(-1)). Neither in mean nor in individual patients were serum and tissue TGF-beta levels correlated with each other. Cell culture experiments on primary bladder cells revealed a 57% decrease in TGF-beta1 mRNA levels in tumour compared with normal epithelial cells. Tumour epithelial cells contained about two times higher levels of TGF-beta2 and TGF-beta3 mRNA than normal epithelial cells. Fibroblasts expressed about the same amount of TGF-beta1 or TGF-beta2 as epithelial cells. Yet, fibroblasts released only 19% and 13% of the amount secreted by tumour epithelial cells into the supernatant. TGF-beta3, on the other hand, was expressed by fibroblasts with higher levels than by epithelial cells. TGF-beta1 was the predominent isoform in bladder tissue and cells at protein as well as on mRNA levels indicating that TGFs-beta2 and -beta3 are of minor importance in bladder cancer. In summary, there is a lack of correlation between TGF-beta serum levels and TGF-beta expression in tumour tissue in bladder cancer.  相似文献   
996.
The cytochrome P450 (P450) proteins constitute a superfamily of enzymes involved in various oxidations and related activities. Polyclonal antibodies raised against bacterial recombinant human P450s varied in specificity, depending upon the individual rabbits used. Several of the antisera raised against P450s 2C10 and 2E1 recognized a number of P450 family 1, 2, and 3 proteins, and two of the less selective antibodies were used to identify cross-reactive epitopes. P450 2C10 peptides reacting with anti-P450 2E1 and P450 2E1 peptides reacting with anti-P450 2C10 were isolated after electrophoresis/immunoblotting and analyzed by Edman degradation. Several of these were in a region near the highly conserved Cys that is a putative axial ligand to the heme. Peptides corresponding to the most conserved regions in this area were synthesized. Anti-P450 2C10 sera did not recognize 14-mer peptides corresponding to the heme-binding region (2C10 410-423 or 2E1 409-422) or the 14-mer peptides immediately C-terminal to these (2C10 425-438 or 2E1 424-437), but anti-P450 2E1 sera showed weak reaction with the latter two synthetic peptides. A longer peptide (29-mer) of P450 2E1 containing parts of both regions (412-440) reacted with both anti-P450 2C10 and anti-P450 2E1 antisera. Antibodies raised against a conjugate of the 29-mer peptide (with hemocyanin) recognized this antigen, the more C-terminal 14-mer peptides (2C10 425-438 and 2E1 424-437), P450s 2C10 and 2E1, and P450s 1A1, 11A1, and 17A. The 29-mer peptide showed considerable alpha-helix structure as judged by CD spectroscopy, in contrast to any of the 14-mers.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
997.
998.
Freeze-fracture and deep-etch electron microscopy were used to investigate the molecular architecture of the Treponema pallidum outer membrane (OM). Freeze-fracture electron microscopy of treponemes freshly harvested from rabbit testes revealed that the intramembranous particles (IMPs) in both the concave and convex OM leaflets were distributed into alternating areas of relatively high and low particle density; in many OM fractures, IMPs formed rows that ran either parallel to or obliquely across the fracture faces. Statistical analysis (runs test) confirmed that the IMPs were nonrandomly distributed in both OM leaflets. Examination of deep-etched specimens revealed that the particles observed in freeze-fractured OMs also were surface exposed. Combined analysis of deep-etched and cross-fractured treponemes revealed that the OM particles were located in regions of the OM away from the endoflagella and closely apposed to the cytoplasmic membrane-peptidoglycan complex. When treponemes were incubated for extended periods with heat-inactivated immune rabbit syphilitic serum, no alteration in the distribution of OM IMPs was detected. In further experiments, approximately 1:1 mixtures of T. pallidum and Escherichia coli or separate suspensions of the nonpathogenic Treponema phagedenis biotype Reiter were fixed at 34 degrees C or after cooling to 0 degree C (to induce lateral phase separations that would aggregate IMPs). Only particles in the T. pallidum OM failed to aggregate in cells fixed at the lower temperature. The combined data suggest that the mobility of T. pallidum rare OM proteins is limited, perhaps as a result of interactions between their periplasmic domains and components of the peptidoglycan-cytoplasmic membrane complex.  相似文献   
999.
OBJECTIVE: To know about the preference for the evening hours in the primary care pediatric consults. DESIGN: A crossover, observational and prospective study. SETTING: Pediatric consult at a health center in the town of Irún, Bidasoa District (Guipúzcoa). PARTICIPANTS: The mothers or companions (171) of the coming children. MEASUREMENTS AND MAIN RESULTS: It was asked to the mothers coming to the consult about their preferences for the hour. The children were divided into three groups: younger than 3 years, 3 to 5 and older than 5. Then, it was taken into account the demand of each group. Projecting the results of the poll on the demand, the children older than 3 prefer the evening hour and between the younger (who represent nearly the half of the pediatric consults), the 50% prefer the morning, and the other half, the evening. There are not significant differences comparing the children from 3 to 5 years to the older than 5. There are significant differences, instead, between the children younger than 3 and any of the two groups of children older than 3: with the group from 3 to 5 (p < 0,01), with the older than 5 (p < 0,05) and with the older than 3 as whole (p < 0,01). CONCLUSIONS: If it would be wanted to adapt the hour to their preferences, it would be necessary to making enable the morning hour for the children younger than 3, and the evening consults for the older.  相似文献   
1000.
This paper presents an artificial neural network (ANN) based approach for the definition of preventive control strategies of autonomous power systems with a large renewable power penetration. For a given operating point, a fast dynamic security evaluation for a specified wind perturbation is performed using an ANN. If insecurity is detected, new alternative stable operating points are suggested, using a hybrid ANN-optimization approach that checks several feasible possibilities, resulting from changes in power produced by diesel and wind generators, and other combinations of diesel units in operation. Results obtained from computer simulations of the real power system of Lemnos (Greece) support the validity of the developed approach  相似文献   
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