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101.
This article describes the basic evaluation process and test methodology employed when temperature extremes for clothing systems must be considered as part of the U.S. Army's Health Hazard Assessment for material in the development and acquisition process. The goals of the evaluation are to select clothing systems that minimize the hazards of heat strain and to predict the heat strain for persons wearing such clothing. Clothing evaluations begin with biophysical assessments that determine the thermal characteristics (vapor permeability and insulation) for textiles via guarded hot plate tests and for clothing systems via thermal manikin tests. The results from biophysical tests can be used to select the textile and/or clothing with the best thermal characteristics. The data from manikin evaluations also can be used in prediction modeling. Human physiological testing is best done in a controlled laboratory environment, although for realism and user acceptability field trials may also be conducted. Proven test and measurement methods must be employed, and tests must control for confounding variables; subjects serve as their own controls, and test environment and procedures are consistent between trials. The process and test methodology described can be applied to the evaluation of civilian clothing systems as well as to the military systems for which they were developed. 相似文献
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MN Bogdan 《Canadian Metallurgical Quarterly》1998,98(3):35-38
The range of prevalence rates for borderline mental disorders is very wide: from 17 to 210 cases per 1000 population. Considerable differences are explained both by a problem of detection of such patients and by certain diagnostic difficulties. Most clinical notions concerning borderline states are insufficiently definite and this has considerable influence on the results of epidemiologic researches. Analysis of the frequency of clinical diagnoses in two Moscow primary care out-patient clinics showed considerable differences which has disappeared under ICD-10 diagnosis. 相似文献
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C Charpin S Garcia L Andrac N Horschowski R Choux MN Lavaut 《Canadian Metallurgical Quarterly》1998,29(9):896-903
Expression of vascular cell adhesion molecules (VCAM) in tumors is associated with endothelial cell activation and may facilitate adherence of carcinomatous cells to the vessel wall, promoting bloodborne metastases. Expression of VCAM was investigated in 202 breast carcinomas using automated (Ventana System) and quantitative (SAMBA image analyzer) immunoperoxidase staining of frozen sections. Positive VCAM immunoreactivity was observed in 83 tumors (41%) (mean immunostained surface, 12.4%; SD, 10.5). The mean area of immunostaining was correlated with clinical and pathologic prognostic indicators and with the immunohistochemical expression in tissue sections of various indicators of cell proliferation, metastatic potential, and drug resistance or sensitivity, evaluated according to the same method. There was no correlation of VCAM immunoreactivity with tumor size, type, or grade or with nodal status. Also, no significant correlation was observed between VCAM and MIB1/Ki67, p53, Bcl-2, E cadherin, CD44v, cathepsin D, CD31, P-gp, ER, PR, or pS2. However, VCAM immunoreactivity was significantly correlated with ELAM and VLA2 (P = .001) and VLAs (P = .008) expression. The results suggest that VCAM expression in breast carcinoma tissue sections is likely not a prognostic indicator. Its practical clinical relevance, if any, must be established by correlation with patients' outcomes and tumor sensitivity to drugs. 相似文献
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MN Sabbagh RT Reid J Corey-Bloom TS Rao LA Hansen M Alford E Masliah A Adem GK Lloyd LJ Thal 《Canadian Metallurgical Quarterly》1998,105(6-7):709-717
The loss of neocortical synapses that occurs in Alzheimer's disease (AD) has been shown to correlate with cognitive decline. In addition, marked losses in the cholinergic system in AD, specifically choline acetyltransferase (ChAT) activity and high affinity presynaptic neuronal nicotinic cholinergic receptors (nAChRs), have also been described. We hypothesized that in AD, the loss of [3H]-ligand binding to nAChRs, which are largely presynaptic, would correlate with changes in two other presynaptic markers: synaptophysin (Syn), a measure of synaptic density, and ChAT activity. The midfrontal (MF) cortex of 36 autopsy confirmed (NIA and CERAD criteria) AD patients (mean death age +/- SD 80.1 +/- 8.4 years) who met NINDS-ADRDA criteria for a clinical diagnosis of probable or possible AD, and 11 nondemented controls (mean death age +/- SD 77.9 +/- 8.0) were examined. Synapse counts were quantified by a dotimmunobinding assay for Syn. ChAT activity was assessed by standard biochemical assays. Nicotinic cholinergic receptor binding was assayed using the high affinity nicotinic agonist [3H]-(+/-)-epibatidine ([3H]-EPI). The mean +/- SD Syn in AD (83.4 +/- 31.9 arbitrary units (AU)/mg protein) was significantly lower than controls (126.1 +/- 19.9, p = 0.0003; t-test). The mean ChAT activity in AD (139.0 +/- 75.6 nmol ACh/hr/100 mg protein) was significantly lower than controls (219.6 +/- 70.8, p = 0.004). The mean [3H]-EPI total binding in AD (6.2 +/- 2.8 fmol/mg protein) was significantly lower than controls (14.8 +/- 3.2; p < 0.0001). Syn correlated with [3H]-EPI binding in AD (r = 0.48, p = 0.006; Pearson) but ChAT did not (r = -0.20, p = 0.34). We conclude that loss of high affinity nAChR binding correlates with loss of synapses in AD. The lack of correlation between [3H]-EPI binding and ChAT activity suggests that the targeted receptor populations may not be located exclusively on cholinergic neurons. 相似文献
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The Saccharomyces cerevisiae targets of rapamycin, TOR1 and TOR2, signal activation of cell growth in response to nutrient availability. Loss of TOR or rapamycin treatment causes yeast cells to arrest growth in early G1 and to express several other physiological properties of starved (G0) cells. As part of this starvation response, high affinity amino acid permeases such as the tryptophan permease TAT2 are targeted to the vacuole and degraded. Here we show that the TOR signalling pathway phosphorylates the Ser/Thr kinase NPR1 and thereby inhibits the starvation-induced turnover of TAT2. Overexpression of NPR1 inhibits growth and induces the degradation of TAT2, whereas loss of NPR1 confers resistance to rapamycin and to FK506, an inhibitor of amino acid import. NPR1 is controlled by TOR and the type 2A phosphatase-associated protein TAP42. First, overexpression of NPR1 is toxic only when TOR function is reduced. Secondly, NPR1 is rapidly dephosphorylated in the absence of TOR. Thirdly, NPR1 dephosphorylation does not occur in a rapamycin-resistant tap42 mutant. Thus, the TOR nutrient signalling pathway also controls growth by inhibiting a stationary phase (G0) programme. The control of NPR1 by TOR is analogous to the control of p70 s6 kinase and 4E-BP1 by mTOR in mammalian cells. 相似文献