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991.
Schaubroeck John; Ganster Daniel C.; Jones James R. 《Canadian Metallurgical Quarterly》1998,83(6):869
This study tested predictions from B. Schneider's (1987) attraction–selection–attrition (ASA) model across 5 organizations (n?=?681). Organization membership and occupational attributes interacted with individuals' turnover intentions to predict several personality variables. Relationships among organization membership, occupation type, and personality were partially mediated by perceived structure. The 3-way interaction analyses indicated that occupation type may compensate for the effects of organizational characteristics in making particular traits more suitable for a given organization. The overall pattern of findings supports the more general ASA predictions, but the findings also suggest a need to develop a more refined conceptualization of the trait homogenization process. The authors also discuss what trait homogenization processes may imply about interpreting findings in organizational behavior research in general and better understanding organizational diversity, culture, and organizations' capabilities in responding to change. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
992.
Asthma health status measurement in clinical practice: validity of a new short and simple instrument
Health status (Quality of Life) questionnaires for use in asthma are generally too long or complex for routine use. A new short and simple measure of health status in asthma has been developed for this purpose. There are two versions, one containing 30 items (AQ30) and the other 20 items (AQ20). This study examined their cross-sectional and longitudinal properties and compared them with those of two established measures--the St. George's Respiratory Questionnaire (SGRQ) and the Asthma Quality of Life Questionnaire (AQLQ). Ninety asthmatic patients (mean age 46 years) participated. Mean post-bronchodilator forced expiratory volume in one second (FEV1) was 73 +/- 25 (SD)% predicted at baseline. Questionnaire data were collected twice, 12 weeks apart. Diary records of peak expiratory flow rate (PEFR) and daily asthma were kept for 14 days. The new questionnaires each took 3 min or less to complete. At baseline they correlated well with the SGRQ and AQLQ and showed the same pattern of correlations with clinical measures of asthma. Change scores for the new questionnaires correlated with those for the established measures. There was no advantage of the AQ30 over the AQ20. The AQ20 provides a simple method for obtaining valid health status estimates of asthmatics in routine clinical practice and has properties similar to more complex research instruments. 相似文献
993.
994.
In the insulin producing cell line RINm5F distribution of serine/threonine specific protein phosphatases type 1 (PP1) and 2A (PP2A) was studied. Using different agents which inhibit or stimulate PP1 and PP2A we found that in membrane and nuclear fractions phosphatase activity was inhibited by okadaic acid (OA), protamine, heparin, and inhibitor-2 in a concentration-dependent manner. C2-ceramide had no effect. In the cytosolic fraction the inhibitory effect of okadaic acid was tenfold higher. Protamine stimulated phosphatase activity at low concentrations and became inhibitory at higher concentrations. Inhibitor-2 and heparin caused a decrease in phosphatase activity whereas C2-ceramide led to a slight activation. The data suggest that in membrane and nuclear fractions of RINmSF cells predominantly PP1 is present, whereas in the cytosol PP1 as well as PP2A can be detected. 相似文献
995.
EM Walker MD Wolfe ML Norton SM Walker MM Jones 《Canadian Metallurgical Quarterly》1998,28(5):300-312
Genetic (hereditary) hemochromatosis is probably the most common autosomal recessive disorder found in white Americans, of whom about 5/1,000 (0.5 percent) are homozygous for the associated gene. The hemochromatosis gene is probably located close to the HLA-A locus on the short arm of chromosome 6. Homozygous individuals may develop severe and potentially lethal hemochromatosis, especially after age 39. Hereditary hemochromatosis involves an increased rate of iron absorption from the gut with subsequent progressive storage of iron in soft organs of the body. Excess iron storage eventually produces pituitary, pancreatic, cardiac, and liver dysfunction and death may result from cardiac arrhythmias, congestive heart failure, and/or hepatic failure or cancer. Early diagnosis can prevent these excess iron-induced problems. Iron overload owing to HLA-linked hereditary hemochromatosis can be distinguished from other causes of hemochromatosis by liver biopsies and interpretations. Patients at risk for genetic hemochromatosis should be screened, identified, and treated as early as age 20 to prevent or minimize the deadly complications of hemochromatosis. Population screening should include measurements of serum iron concentration, total iron binding capacity (TIBC), percent saturation of transferrin, and serum ferritin concentrations. Family members of hereditary hemochromatosis patients are at increased risk and should be tested. Screening, identification and early treatment (phlebotomies, sometimes in combination with the use of Desferal or other iron-chelating agents) may help prevent or reduce iron-related organ damage and premature deaths. Early diagnosis and treatment will reduce the population of aging individuals with severe, complicated hemochromatosis and dramatically reduce medical costs (billions of U.S. dollars per annum) associated with the management of this disease. 相似文献
996.
Oscillation behaviour of the oxidation of CO (0.2–2.2%) in air over Pt wire coils and over Pt/Al2O3 catalysts deposited onto the coils (pellistors) has been investigated. The waveforms differ considerably between the two catalytic systems. Over unsupported Pt at 240–260° C, regular oscillations were accompanied by slowly declining activity and by deposition of carbon. Over supported Pt at 110–180°C, relatively complex but sustained oscillation occurred by a different mechanism. This oscillation was greatly enhanced by H2 (0.25–1.0%), and may involve fluctuations in the concentrations of CO and H2 around the supported catalyst. 相似文献
997.
PE Young NJ Beasley DJ Houghton DJ Husband M Currie B Chislett AS Jones 《Canadian Metallurgical Quarterly》1998,23(6):528-532
A new short questionnaire to assess the quality of life of head and neck patients has been designed at the University of Liverpool Head and Neck Oncology Department. The questionnaire is short, simple and can be easily completed by a patient whilst in the waiting room before consultation. It is filled in 6 months after completion of treatment and shows very good correlation with the standard long exhaustive questionnaires that are difficult to complete on every patient in a busy National Health Service clinic. The University of Liverpool questionnaire provides a simple score from 0%-100% which should prove valuable in the assessment of quality of care and help with decisions regarding treatment options in head and neck cancer patients. 相似文献
998.
A 60-year-old male patient was urgently admitted to the hospital with chest pain, anemia and shock. The echocardiographic examination revealed myocardial tamponade and, unexpectedly, a mobile mass in the right atrium, prolapsing in the right ventricle which was indicative of myxoma. The patient underwent pericardiocentesis which showed the presence of blood. Cardiac surgery was then performed to remove the tumor which was found to originate in the right atrial appendage. There were some adhesions between the atrial appendage and the anterior wall of the right ventricle. The tamponade was due to a trauma of some small pericardial arteries in the adhesion area. The presence of tamponade and right atrial myxoma, is the peculiar finding of the reported case. 相似文献
999.
GD Jackson SR Williams RO Weller N van Bruggen NE Preece SC Williams WH Butler JS Duncan 《Canadian Metallurgical Quarterly》1994,18(1):57-66
Previous research has indicated that individual foods or beverages are ingested independently and do not produce adjustments to the intake of other constituents in the diet (de Castro, 1993; Wilson, 1991). In order to eliminate time of day as a potential contaminant, the present study investigated the accommodation of foods and beverages into the amount ingested at large evening meals only. Adults (n = 601) were paid to maintain detailed diaries of the timings, quantities and preparation techniques of everything they ingested for seven consecutive days. With the exceptions of soup, beef and chicken, 12 out of 15 types of drinks or foods were found to add to the total calories ingested in evening meals without displacing calories ingested in other forms, while ingestion of non-caloric diet sodas was not associated with differences in intake. The fat and protein, but not carbohydrate, contents of the items correlated with a measure of the satiating properties of the particular food or beverage, namely the correlation between the amount ingested of the particular type and the amounts of other nutrients ingested in the meal. The results confirm that intake at a meal is quite elastic and can be significantly influenced by the presence or absence of particular components of the meal and their constituents. 相似文献
1000.
A Khateb P Fort S Williams M Serafin M Mühlethaler BE Jones 《Canadian Metallurgical Quarterly》1998,86(3):937-947
The potential influence of GABAergic input to cholinergic basalis neurons was studied in guinea-pig basal forebrain slices. GABA and its agonists were applied to electrophysiologically-identified cholinergic neurons, of which some were labelled with biocytin and confirmed to be choline acetyltransferase-immunoreactive. Immunohistochemistry for glutamate decarboxylase was also performed in some slices and revealed GABAergic varicosities in the vicinity of the biocytin-filled soma and dendrites of electrophysiologically-identified cholinergic cells. From rest (average - 63 mV), the cholinergic cells were depolarized by GABA. The depolarization was associated with a decrease in membrane resistance and diminution in firing. The effect was mimicked by muscimol, the specific agonist for GABA(A) receptors, and not by baclofen, the specific agonist for GABA(B) receptors, which had no discernible effect. The GABA- and muscimol-evoked depolarization and decrease in resistance were found to be postsynaptic since they persisted in the presence of solutions containing either high Mg2+/low Ca2+ or tetrodotoxin. They were confirmed as being mediated by a GABA(A) receptor, since they were antagonized by bicuculline. The reversal potential for the muscimol effect was estimated to be approximately -45 mV, which was -15 mV above the resting membrane potential. Finally, in some cholinergic cells, spontaneous subthreshold depolarizing synaptic potentials (average 5 mV in amplitude), which were rarely associated with action potentials, were recorded and found to persist in the presence of glutamate receptor antagonists but to be eliminated by bicuculline. These results suggest that GABAergic input may be depolarizing, yet predominantly inhibitory to cholinergic basalis neurons. 相似文献