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41.
With the object of assessing the long-term prognosis and the frequencies of recurrence and remission in women chronic low abdominal pain without laparoscopically visible cause, questionnaire were sent in 1985 and 1991 to 55 women who had been submitted to laparoscopy in 1982-1984 for this reason. These women had been told that there was no demonstrable explanation of the pain experienced and were then discharged. 65% and 55% respectively had experienced and unfavourable course with considerable and continued symptoms. Only 22% stated in both investigations that they had experienced a favourable course and that they were, by and large, free from pain. 36% changed from an unfavourable to a favourable course or the reverse. The assessment made by the women was confirmed by a series of subordinate questions and this demonstrated a marked difference between the favourable and unfavourable courses of the condition. It is concluded that laparoscopy with exclusion of significant pathology is not, in itself, satisfactory as treatment of this patient group and that no improvement occurs in the course of time. The condition varies greatly with many recurrences and remissions and, for this reason, uncontrolled reports of the therapeutic effects are of no significance. When compared with the literature, it is suggested that this patient group should be referred early in the course of the condition to a therapist with specialist psychological/sexological insight and/or to a physiotherapist with interest in this patient group. 相似文献
42.
43.
Regression analyses of counts and rates: Poisson, overdispersed Poisson, and negative binomial models. 总被引:1,自引:0,他引:1
The regression models appropriate for counted data have seen little use in psychology. This article describes problems that occur when ordinary linear regression is used to analyze count data and presents 3 alternative regression models. The simplest, the Poisson regression model, is likely to be misleading unless restrictive assumptions are met because individual counts are usually more variable ("overdispersed") than is implied by the model. This model can be modified in 2 ways to accommodate this problem. In the overdispersed model, a factor can be estimated that corrects the regression model's inferential statistics. In the second alternative, the negative binomial regression model, a random term reflecting unexplained between-subject differences is included in the regression model. The authors compare the advantages of these approaches. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
44.
John Drennan David R. Clarke Richard H. J. Hannink Thomas M. Shaw 《Journal of the American Ceramic Society》1994,77(8):2001-2008
The microstructure, average grain size, and density of Mg-PSZ sintered with SrO and SiO2 additions are found to depend on the partial pressure of oxygen in the sintering atmosphere. Over the range of 10−1 to 10° atm, both the average grain size and the density increase with oxygen partial pressure, for a constant SrO/SiO2 ratio. The partial pressure of oxygen also affects the microstructural distribution of the remnant liquid phase. At high partial pressures the liquid phase is uniformly distributed, whereas at lower oxygen pressures it is preferentially located near the surface. It is proposed that the microstructure produced by sintering is the result of a competition between liquid-phase-enhanced densification and the migration of the liquid phase to the free surface. The migration is attributed to vaporization of MgO from the liquid phase which increases with decreasing partial pressure of oxygen. 相似文献
45.
In this study we have examined (1) the integrated function of the mitochondrial respiratory chain by polarographic measurements and (2) the activities of the respiratory chain complexes I, II-III, and IV as well as the ATP synthase (complex V) in free mitochondria and synaptosomes isolated from gerbil brain, after a 30-min period of graded cerebral ischaemia. These data have been correlated with cerebral blood flow (CBF) values as measured by the hydrogen clearance technique. Integrated functioning of the mitochondrial respiratory chain, using both NAD-linked and FAD-linked substrates, was initially affected at CBF values of approximately 35 ml 100 g-1 min-1, and declined further as the CBF was reduced. The individual mitochondrial respiratory chain complexes, however, showed differences in sensitivity to graded cerebral ischaemia. Complex I activities decreased sharply at blood flows below approximately 30 ml 100 g-1 min-1 (mitochondria and synaptosomes) and complex II-III activities decreased at blood flows below 20 ml 100 g-1 min-1 (mitochondria) and 35-30 ml 100 g-1 min-1 (synaptosomes). Activities declined further as CBF was reduced below these levels. Complex V activity was significantly affected only when the blood flow was reduced below 15-10 ml 100 g-1 min-1 (mitochondria and synaptosomes). In contrast, complex IV activity was unaffected by graded cerebral ischaemia, even at very low CBF levels. 相似文献
46.
Judge Timothy A.; Jackson Christine L.; Shaw John C.; Scott Brent A.; Rich Bruce L. 《Canadian Metallurgical Quarterly》2007,92(1):107
The present study estimated the unique contribution of self-efficacy to work-related performance controlling for personality (the Big 5 traits), intelligence or general mental ability, and job or task experience. Results, based on a meta-analysis of the relevant literatures, revealed that overall, across all studies and moderator conditions, the contribution of self-efficacy relative to purportedly more distal variables is relatively small. Within moderator categories, there were several cases in which self-efficacy made unique contributions to work-related performance. For example, self-efficacy predicted performance in jobs or tasks of low complexity but not those of medium or high complexity, and self-efficacy predicted performance for task but not job performance. Overall, results suggest that the predictive validity of self-efficacy is attenuated in the presence of individual differences, though this attenuation does depend on the context. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
47.
I Beck-Speier N Dayal C Denzlinger C Haberl KL Maier A Ziesenis J Heyder 《Canadian Metallurgical Quarterly》2003,71(3-4):217-234
Recent studies have shown that long-term in vivo exposure of dogs to neutral sulfur(IV)/sulfite aerosols induces mild inflammatory reactions, whereas the combination of neutral sulfite with acidic sulfur(VI)/sulfate aerosols evokes less pronounced effects. To understand underlying mechanisms, we studied in vitro the role of lipid mediators in the responses of alveolar macrophages (AMs) to sulfur-related compounds under neutral (pH 7) or moderate acidic (pH 6) conditions. Canine AMs incubated with sulfite at pH 7 released threefold higher amounts of platelet-activating factor than control (P < 0.005). Generation of arachidonic acid, leukotriene B4, 5-hydroxy-eicosatetraenoic acid, prostaglandin E2, thromboxane B2 and 12-hydroxyheptadecatrienoic acid increased twofold (P < 0.0005). However, these metabolites remained unchanged following incubation of AMs with sulfite at pH 6 or with sulfate at pH 7 or pH 6. Mediator release by sulfite-treated AMs at pH 7 stimulated respiratory burst activity of neutrophils. Inhibition of MAPK pathway by PD 98059, of cytosolic (cPLA2) and secretory phospholipases A2 by AACOCF3 and thioetheramide-PC, respectively, reduced sulfite-induced eicosanoid formation in AMs. Sulfite activated cPLA2 activity twofold at pH 7. This mechanism of sulfite-stimulated responses in phospholipid metabolism predicts that chronic exposure to sulfur(IV)/sulfite is associated with a considerable health risk. 相似文献
48.
Effects of process-control agents on mechanical alloying of nanostructured aluminum alloys 总被引:1,自引:0,他引:1
L. Shaw J. Villegas H. Luo M. Zawrah D. Miracle 《Metallurgical and Materials Transactions A》2003,34(1):159-170
The effects of the process-control agents (PCAs) stearic acid and methanol on the mechanical alloying (MA) of a nanostructured
aluminum alloy (Al93Fe3Ti2Cr2) have been investigated. The dependency of the powder-particle sizes, grain sizes, atomic-level strains, lattice parameters,
formation of solid solutions, and microstructural evolution of the aluminum alloy on the types of PCAs and their concentrations
have been studied using a variety of analytical instruments including X-ray diffraction scanning electron microscopy, and
transmission electron microscopy. The results clearly indicate that prevention of excessive cold welding of Al particles can
be achieved by the addition of a PCA at the expense of reductions in the grain size, formation rate of solid solutions, and
rate of microstructural refinement, all of which are desired in MA of the Al alloy. Furthermore, a PCA that is more effective
in preventing excessive cold welding will also impose more hindrance to the MA process. These phenomena have been discussed
in the light of the adsorption of the PCA on the metal surface and the lubricating function of the PCA. 相似文献
49.
Transcortical dialysis was employed to investigate the effects of subcutaneous (s.c.) injections of RJR-2403 (1.2-7.2 mumol/kg) on extracellular levels of acetylcholine (ACh), norepinephrine (NE), dopamine (DA), and serotonin (5-HT) in rat. Systemic administration of RJR-2403 produced a 90% increase of cortical extracellular ACh levels that persisted for up to 90 minutes after injection. Norepinephrine and DA release were increased 124% and 131% above basal values, respectively. Serotonin (5-HT) levels in the dialysate were also significantly elevated by RJR-2403 (3.6 mumol/kg, s.c.) 70% above baseline at 90 minutes post-injection. Comparison of these responses to those of (-)nicotine from a previous study reveals little difference between the two compounds in their ability to influence cortical neurotransmitter release following systemic administration. 相似文献
50.