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91.
JC Wyatt S Paterson-Brown R Johanson DG Altman MJ Bradburn NM Fisk 《Canadian Metallurgical Quarterly》1998,317(7165):1041-1046
OBJECTIVE: To evaluate the effectiveness of an educational visit to help obstetricians and midwives select and use evidence from a Cochrane database containing 600 systematic reviews. DESIGN: Randomised single blind controlled trial with obstetric units allocated to an educational visit or control group. SETTING: 25 of the 26 district general obstetric units in two former NHS regions. SUBJECTS: The senior obstetrician and midwife from each intervention unit participated in educational visits. Clinical practices of all staff were assessed in 4508 pregnancies. INTERVENTION: Single informal educational visit by a respected obstetrician including discussion of evidence based obstetrics, guidance on implementation, and donation of Cochrane database and other materials. MAIN OUTCOME MEASURES: Rates of perineal suturing with polyglycolic acid, ventouse delivery, prophylactic antibiotics in caesarean section, and steroids in preterm delivery, before and 9 months after visits, and concordance of guidelines with review evidence for same marker practices before and after visits. RESULTS: Rates varied greatly, but the overall baseline mean of 43% (986/2312) increased to 54% (1189/2196) 9 months later. Rates of ventouse delivery increased significantly in intervention units but not in control units; there was no difference between the two types of units in uptake of other practices. Pooling rates from all 25 units, use of antibiotics in caesarean section and use of polyglycolic acid sutures increased significantly over the period, but use of steroids in preterm delivery was unchanged. Labour ward guidelines seldom agreed with evidence at baseline; this hardly improved after visits. Educational visits cost pound860 each (at 1995 prices). CONCLUSIONS: There was considerable uptake of evidence into practice in both control and intervention units between 1994 and 1995. Our educational visits added little to this, despite the informal setting, targeting of senior staff from two disciplines, and donation of educational materials. Further work is needed to define cost effective methods to enhance the uptake of evidence from systematic reviews and to clarify leadership and roles of senior obstetric staff in implementing the evidence. 相似文献
92.
Infection in a wound represents a colony count of 10(5) or greater. Contamination is the presence of many surface organisms. Moist wound healing, not dehydration, protects and prepares the wound for coverage and closure. Relief of pain is a critical factor in achieving healing: a biological or pharmaceutical device can achieve protection and facilitate healing. 相似文献
93.
M Amano N Baumgarth MD Dick L Brossay M Kronenberg LA Herzenberg S Strober 《Canadian Metallurgical Quarterly》1998,161(4):1710-1717
We have used multicolor FACS analysis, immunohistology, and functional assays to study the expression of CD1 on B cell subsets from normal and beta 2m-/- mice. Two B cell subpopulations were identified that express high levels of CD1 in normal mice: splenic marginal zone B cells (IgMhigh IgDlow CD21high CD24intermediate CD23- CD43-) and a newly identified subpopulation of follicular B cells. The latter cells are unusual, because they are IgDhigh CD23+, like follicular B cells, but express high levels of CD21 and IgM, an expression pattern that is associated with marginal zone B cells. Therefore, the high-level expression of CD1 and CD21 was found to be closely associated on splenic B cells. Immunohistology confirmed the expression of CD1 on marginal zone B cells and on clusters of B cells in splenic follicles. Both the high-level CD1 expression by these cells and the low-level CD1 expression by subpopulations of B cells in the spleen, lymph node, peritoneal cavity, and bone marrow were markedly reduced in beta 2m-/- mice. Despite this, a CD1-restricted T cell clone proliferated vigorously in response to LPS-activated spleen cells that had been obtained from both beta 2m-/- and wild-type mice. This response was inhibited by the 3C11 anti-CD1 mAb. These results show the heterogeneity of B cell subsets in their expression of the beta 2m-dependent form of CD1. They further suggest that a beta 2m-independent form of CD1 is expressed on B cells that can stimulate T cells; however, this form is not easily visualized with the anti-CD1 mAb used here. 相似文献
94.
Na+ currents in adult rat large dorsal root ganglion neurons were recorded during long duration voltage-clamp steps by patch clamping whole cells and outside-out membrane patches. Na+ current present >60 ms after the onset of a depolarizing pulse (late Na+ current) underwent partial inactivation; it behaved as the sum of three kinetically distinct components, each of which was blocked by nanomolar concentrations of tetrodotoxin. Inactivation of one component (late-1) of the whole cell current reached equilibrium during the first 60 ms; repolarizing to -40 or -50 mV from potentials of -30 mV or more positive gave rise to a characteristic increase in current (tau >/= 5 ms), attributed to removal of inactivation. A second component (late-2) underwent slower inactivation (tau > 80 ms) at potentials more positive than -80 mV, and steady-state inactivation appeared complete at -30 mV. In small membrane patches, bursts of brief openings (gamma = 13-18 pS) were usually recorded. The distribution of burst durations indicated that two populations of channel were present with inactivation rates corresponding to late-1 and late-2 macroscopic currents. The persistent Na+ current in the whole cell that extended to potentials more positive than -30 mV appeared to correspond to sporadic, brief openings that were recorded in patches (mean open time approximately 0.1 ms) over a wide potential range. None of the three types of gating described corresponded to activation/inactivation gating overlap of fast transient currents. 相似文献
95.
96.
97.
The activity of pro-oxytocin/neurophysin (pro-OT/Np)-processing enzymes was determined in human granulosa cells, follicular fluids and purified secretory granules of corpora lutea. We detected the presence of an endoprotease which releases OT-Gly10-Lys11-Arg12 on cleavage of the synthetic pro-OT/Np(1-20) peptide after the dibasic Lys11-Arg12 doublet. This endoprotease was inhibited by EDTA, but was not affected by phenylmethanesulfonyl fluoride and pepstatin. Enzymatic activity was markedly reduced by replacement of L-Arg by D-Arg in the basic amino acid doublet of the substrate. The molecular weight of this enzyme was estimated to be 60 kDa. These features closely resembled those of the endoprotease identified in the bovine pituitary. The endoprotease is a metalloenzyme, specific for the Lys-Arg doublet. We also detected a carboxypeptidasic activity, inhibited by guanidinoethane-mercaptosuccinic acid. In the light of our previous detection of the processing intermediates, OT-Gly-Lys-Arg, OT-Gly-Lys and OT-Gly, in human ovary, these observations are in favour of a pro-OT/Np-processing pathway in the human ovary comparable with that in the bovine ovary. Moreover, these results confirm that oxytocin post-translational processing occurs in the human ovary and strongly suggest that pro-OT/Np is synthesized locally. 相似文献
98.
Méndez RO Bueno K Campos N López D Wyatt CJ Ortega MI 《Archivos latinoamericanos de nutrición》2005,55(2):187-193
Developing countries diets are based on a variety of plant foods that often are the main suppliers of important amounts of iron (Fe) and zinc (Zn). The objectives of this study were 1) to measure the total and dialyzable amounts of Fe and Zn in foods from Northern Mexico (Sonora) and from Southern Mexico (Oaxaca) and 2) to evaluate the effect of meat content of diets on the dialyzable amount of Fe and Zn. Methods to calculate the total dialyzable amount of Fe and Zn, were those of the AOAC and of Shen et al. Total Fe in e northern Mexican foods went from 0.78 +/- 0.0 to 11.59 +/- to 0.03 mg/ 100g (dry weight, DW); in southern Mexican foods the same micronutrient amounts were 0.86 +/- 0.18 to 8.8 +/- 0.57 mg/100 g (BS). Total Zn values were 0.91 +/- 0.00 to 13.58 +/- 0.05 mg/100 g (DW) in Sonora, and 0.64 +/- 0.18 to 20.80 +/- 0.33 mg/100 g (DW) in Oaxaca. In northern Mexico, foods dialyzable Fe had values from 0.1 +/- 0.04% to 10.6 +/- 0.36% and for Zn from 4.0 +/- 0.21% to 55.32 +/- 0.14%. Meanwhile, the range of values of dialyzable Fe for foods from Oaxaca were from 0.22 +/- 0.06% to 9.40 +/- 0.14% for and from 2.41 +/- 0.26% to 54.27 +/- 1.49% for dialyzable Zn. The average value for dialyzable Fe was higher in the foods that contained meat or meat products (p= 0.001). 相似文献
99.
Victor T. Wyatt Alberto Nuñez Thomas A. Foglia William N. Marmer 《Journal of the American Oil Chemists' Society》2006,83(12):1033-1039
Novel oligomeric prepolymers were synthesized by acid-catalyzed condensation of glycerol with iminodiacetic, azelaic, or succinic
acid. The prepolymers were obtained, on average, in 62% yield and were characterized by 13C NMR, 1H NMR, matrix-assisted laser desorption ionization-time of flight-mass spectrometry, and gel permeation chromatography. The
synthesized oligomers had an average M.W. of 1543 Daltons (average polydispersity (PD)=1.34, average degree of polymerization
(DOP)=5.5). Hyperbranching was evident in the oligomers produced when using azelaic acid and succinic acid as co-monomers
with glycerol, whereas the reaction between iminodiacetic acid and glycerol resulted in linear products bearing cyclic urethane
structures. 相似文献
100.
Increased potassium fertilization may be important in broccoli transplant growth. Recommended amounts of water soluble 20N-8.7P-16.6K were supplemented with varying concentrations of K as KCl applied at intervals during broccoli transplant development. Transplant growth and subsequent broccoli yields were studied in greenhouse and field tests.Fertilization with supplemental K significantly increased broccoli transplant fresh and dry weight, leaf area, stem diameter and plant height over the control. Effect of number of applications was generally dependent on K concentration and age of the broccoli seedling at the first fertilization. High K concentrations (> 2098 ppm) applied two weeks after planting were detrimental to broccoli transplant growth.In two field tests, supplemental K applied to transplants had no effect on broccoli yield. No significant differences were found between supplementing fertilizer with K and hardening transplants in a cold frame for two weeks. Incidence of hollow stem was increased in one test by application of 1000ppm K. Two applications per week caused significant increases in yield, head diameter and hollow stem when compared with one application per week. 相似文献