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51.
One way hospitals complicate themselves is by increasing the participation of clinical professionals and middle managers in making strategic decisions. Using a survey methodology this article investigates the relationships between the participation of clinical professionals (MDs and RNs) and middle managers with hospital costs, as well as the possible moderating effect of strategic complexity. 相似文献
52.
MV Kamath J Halton A Harvey S Turner-Gomes A McArthur RD Barr 《Canadian Metallurgical Quarterly》1998,12(3):635-640
Lower levels of baseline ventilatory function have consistently been associated with increased risk of cardiovascular mortality in prospective studies, but the underlying mechanisms are not known. Increased risk of coronary heart disease is associated with higher serum insulin levels. This report examines the relationship between ventilatory function and indirect measures of insulin resistance. Cross-sectional data from 922 nondiabetic participants in the Normative Aging Study were analysed using multiple linear regression models with adjustment for potential confounders. Forced vital capacity (FVC) and forced expiratory volume in one second (FEV1) were examined in relation to indicators of insulin resistance, i.e. fasting insulin and the fasting insulin resistance index (FIRI). Diabetics were excluded because impaired insulin secretion interferes with the validity of these as measures of insulin resistance. Fasting insulin and FIRI were negatively correlated with FVC and FEV1 (all p< 0.001). These associations persisted after adjusting for potential confounders including age, height, body mass index, waist to hip circumference ratio, physical activity, alcohol intake and smoking in separate multiple linear regression models, for both insulin (all p< or =0.0008) and FIRI (all p< or =0.0001). Negative cross-sectional associations between ventilatory function and indirect measures of insulin resistance were found in nondiabetic males. Insulin resistance may contribute to the previously unexplained association between ventilatory function impairment and cardiovascular mortality. Mechanisms underlying the relationship between insulin resistance and decreased ventilatory function remain to be elucidated. 相似文献
53.
DP Berry KG Harding MR Stanton B Jasani HP Ehrlich 《Canadian Metallurgical Quarterly》1998,102(1):124-31; discussion 132-4
The closure of ungrafted sacrococcygeal pilonidal sinus excisional wounds was studied in 15 patients. Wound punch biopsies were taken on a regular basis, and histologic sections were made. To document changes, computer-assisted morphometric image analysis was employed. Initial average wound depth was 37.8 +/- 4.6 mm, and complete closure (0 wound depth) was reached by 68 days. Wound contraction contributed 88 percent to wound closure, whereas the deposition of scar only contributed 12 percent. Maximum cells density within granulation tissue was reached by day 18. Myofibroblasts, identified by alpha-smooth muscle actin immunostaining, first appeared on day 11. Unlike those observed in laboratory animals, myofibroblasts were a minor cell population of granulation tissue, never exceeding 10 percent of the cells. The pattern of collagen fiber organization was documented by polarized light microscopy of Sirius red-stained sections. Early granulation tissue collagen fibers demonstrated a fine greenish birefringence, whereas more mature granulation tissue collagen fibers were thicker, displaying orange-yellowish birefringence. Myofibroblasts were associated exclusively with thicker collagen fibers, whereas fibroblasts were associated with both fine and thick collagen fibers. It is proposed that human wound contraction involves a volume change whereby normal dermal and adipose tissues are pulled into the defect by forces generated within fibroblasts. 相似文献
54.
We report some preliminary measurement of the erosion rate of plasma dumps when bombarded with 100 keV He+ ions at high power density ( 1 MW/m2). The expected erosion rates, based on measurements of He blistering that were made at lower power density ( 0.3 MW/m2), indicate a potentially serious problem for fusion reactors. Our tests use a reactorlike power density and produce He blisters at a rate that is slower than predicted by 2 to 4 orders of magnitude, depending on the temperature of the molybdenum target. 相似文献
55.
Shen TJ; Ho NT; Zou M; Sun DP; Cottam PF; Simplaceanu V; Tam MF; Bell DA Jr; Ho C 《Protein engineering, design & selection : PEDS》1997,10(9):1085-1097
A hemoglobin expression system in Escherichia coli is described. In order
to produce authentic human hemoglobin, we need to co-express both
methionine aminopeptidase and globin genes under the control of a strong
promoter. We have constructed three plasmids, pHE2, pHE4 and pHE7, for the
expression of human normal adult hemoglobin and a plasmid, pHE9, for the
expression of human fetal hemoglobin, in high yields. The globin genes can
be derived from either synthetic genes or human globin cDNAs. The extra
amino-terminal methionine residues of the expressed globins can be removed
by the co-expressed methionine aminopeptidase. The heme is inserted
correctly into the expressed alpha- globin from our expression plasmids. A
fraction (approximately 25%) of the heme is not inserted correctly into the
expressed beta- or gamma- globin. However, the incorrectly inserted hemes
can be converted into the correct conformation by carrying out a simple
oxidation-reduction process on the purified hemoglobin molecule. We have
investigated the functional properties of the expressed hemoglobins by
measuring their oxygen-binding properties and their structural features by
obtaining their 1H-NMR spectra. Our results show that authentic human
normal adult and fetal hemoglobins can be produced from our expression
plasmids in E. coli and in high yields. Our expression system allows us to
design and to produce any recombinant hemoglobins needed for our research
on the structure-function relationship in hemoglobin.
相似文献
56.
T. A. Foglia P. A. Barr A. J. Malloy M. J. Costanzo 《Journal of the American Oil Chemists' Society》1977,54(11):A870-A872
The oxidation of the alkali metal salts of oleic and undecylenic acid with ruthenium and osmium tetroxides is reported. The oxidants are used in catalytic amounts in conjunction with an excess of the in-expensive cooxidant sodium hypochlorite. Ruthenium tetroxide cleaves the carbon-carbon double bond of potassium oleate, to give pelargonic and gives sebacic acid. With osmium tetroxide, hydroxylation of the double bond of potassium oleate gives a 95% yield oferythro-9,10-dihydroxystearic acid. The osmium tetroxide oxidation of sodium undecylenate results in the formation of 10,11-dihydroxyundecanoic acid and the cleavage product sebacic acid in varying yields. 相似文献
57.
M. J. Kappers M. Vaarkamp J. T. Miller F. S. Modica M. K. Barr J. H. van der Maas D. C. Koningsberger 《Catalysis Letters》1993,21(3-4):235-244
The adsorption of carbon monoxide on a non-acidic Pt/K-LTL catalyst has been studied by diffuse reflectance and transmission IR spectroscopy. The CO spectrum is strongly dependent on the experimental conditions. Adsorption on the small Pt clusters in the presence of water gives linear-CO bands between 2060 and 1990 cm–1 and a bridging-CO band around 1800 cm–1. In the absence of water, the linear bands are red shifted to about 1940 and 1720 cm–1, respectively. The frequency shift is attributed to an ion-dipole interaction between adsorbed CO and support cations. The ion-dipole interaction is screened by the adsorbed water leading to a smaller red shift in the CO stretching frequency. 相似文献
58.
R. Barré 《Scientometrics》1991,22(1):95-112
The goal of this article is to show that it is possible to construct an index to measure a country's relative specialization in different scientific fields in a way which is both reliable and relevant for macro-strategic analysis. We will call this index a Revealed Scientific Advantages Index. The technical problem to be discussed is one of aggregation: how can we be sure that an index calculated for a small number of relatively large fields does not mask significant policy needs synthetic measures which are easy to interpret. We will show that the Revealed Scientific Advantages approach offers the possibility of building them. The study itself is based on figures obtained through an exploitation of the INIST/CNRS PASCAL database classification of science. 107 sub-fields of this classification were initially used to determine the areas of specialization for 11 countries (revealed national advantages). Clustering techniques were then used to aggregate this data and 13 specific fields were identified. The science policy information produced during the study concerned these 13 fields. It proved to be both easily understandable and relevant for macro-strategic analysis. 相似文献
59.
Apoptosis and its role in human disease 总被引:1,自引:0,他引:1
In a landmark paper published over two decades ago, Kerr et al. proposed the term apoptosis "for a hitherto little recognized mechanism of controlled cell deletion, which appears to play a complementary but opposite role to mitosis in the regulation of animal cell populations". In the ensuing years, this natural cell death process was studied at the basic science level, primarily with a view to understanding its roles in cancer and in the development and maintenance of the immune system. More recently, however, evidence has suggested a role for the failure of normal apoptosis control in many of the major diseases of the industrialized world. Though complex, apoptosis appears amenable to therapeutic intervention. The range of modern pharmaceutical strategies available to treat such disregulated gene-directed processes offers promise for advances in the control of cancer, immune system and neurodegenerative disorders, heart disease, and perhaps even the aging process itself. 相似文献
60.
SR Cohen ML Corrigan FL Bookstein CA Trotman A Burdi M Barr 《Canadian Metallurgical Quarterly》1995,6(3):184-189
Trisomy 21 develops as a result of nondisjunction of two homologous chromosomes during either the first or second meiotic division. One of the more important consequences of these genetic alterations is the predictable, although variable disturbance in the architecture of the craniofacial region [1]. Postnatal craniofacial morphology has been extensively studied in Down's syndrome (DS). However, little information is available on human prenatal development of the head and face in such patients. The time at which changes in craniofacial phenotype first emerge in Down's syndrome fetuses and at which physical growth begins to diverge from normal is unknown. To explore these questions, we compared prenatal craniofacial growth in 50 Down's syndrome fetuses with that of 555 fetuses judged to be "typical for body weight and age" using the method of log-linear allometry [2]. 相似文献