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991.
L Badano D Bertoli D Astengo L Carratino G DeGaetano GC Passerone A Camerieri S Gramenzi O Magaja L Fazzini 《Canadian Metallurgical Quarterly》1993,14(12):1602-1609
Doppler echocardiographic characteristics of normally functioning Allcarbon prostheses were studied in 149 consecutive patients with 157 valves in the mitral (n = 73) and aortic (n = 84) positions whose function was considered normal by clinical and echocardiographic evaluation. In the mitral position, the mean gradient and the effective mitral orifice area were not significantly different in either the 25-mm or the 31-mm size valves (from 5 +/- 1 to 4 +/- 1 mmHg and from 2.2 +/- 0.6 to 2.8 +/- 0.9 cm2, respectively; P = ns for both). Conversely, peak gradient was significantly and inversely correlated to actual orifice area (r = -0.70; P < 0.0006), decreasing from 15 +/- 3 mmHg in the 25-mm size valve to 9 +/- 1 mmHg in the 31-mm size. In the aortic position, the mean gradient was 29 +/- 8 mmHg in the 19-mm size valve; it decreased to 8 +/- 2 mmHg in the 29-mm size. Effective prosthetic aortic valve area, calculated using the continuity equation, ranged between 0.9 +/- 0.1 cm2 for the 19-mm size valve to 4.1 +/- 0.7 cm2 for the 29-mm size. By analysis of variance, effective prosthetic aortic valve area differentiated various valve sizes (F = 25.3; P < 0.0001) better than peak (F = 5.34; P = 0.012) or mean (F = 4.34; P = 0.0052) gradients alone, and it correlated better with actual orifice area (r = 0.89, r = -0.70 and r = -0.65, respectively).(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
992.
993.
W. R. Morrison 《Starch - St?rke》1981,33(12):408-410
It is proposed that lipids on the surface of starch granules should be called “starch surface lipids”, and that those inside the granules should be called “internal starch lipids”. Starch surface lipids appear to be derived from the “non-starch lipids” which are either free or bound to proteins in the starch-bearing tissues. In cereals the internal starch lipids are exclusively monoacyl lipids, and they are quite different in composition from the starch surface lipids and non-starch lipids. In some recent publications lipids purporting to be internal starch lipids evidently include substantial quantities of non-starch or surface lipids. 相似文献
994.
Florine Seidel Robert Kleemann Wim van Duyvenvoorde Nikki van Trigt Nanda Keijzer Sandra van der Kooij Cees van Kooten Lars Verschuren Aswin Menke Amanda J. Kiliaan Johnathan Winter Timothy R. Hughes B. Paul Morgan Frank Baas Kees Fluiter Martine C. Morrison 《International journal of molecular sciences》2022,23(18)
Background: Chronic inflammation is an important driver in the progression of non-alcoholic steatohepatitis (NASH) and atherosclerosis. The complement system, one of the first lines of defense in innate immunity, has been implicated in both diseases. However, the potential therapeutic value of complement inhibition in the ongoing disease remains unclear. Methods: After 20 weeks of high-fat diet (HFD) feeding, obese Ldlr-/-.Leiden mice were treated twice a week with an established anti-C5 antibody (BB5.1) or vehicle control. A separate group of mice was kept on a chow diet as a healthy reference. After 12 weeks of treatment, NASH was analyzed histopathologically, and genome-wide hepatic gene expression was analyzed by next-generation sequencing and pathway analysis. Atherosclerotic lesion area and severity were quantified histopathologically in the aortic roots. Results: Anti-C5 treatment considerably reduced complement system activity in plasma and MAC deposition in the liver but did not affect NASH. Anti-C5 did, however, reduce the development of atherosclerosis, limiting the total lesion size and severity independently of an effect on plasma cholesterol but with reductions in oxidized LDL (oxLDL) and macrophage migration inhibitory factor (MIF). Conclusion: We show, for the first time, that treatment with an anti-C5 antibody in advanced stages of NASH is not sufficient to reduce the disease, while therapeutic intervention against established atherosclerosis is beneficial to limit further progression. 相似文献
995.
Jason S. Moore Keith D. Morrison Alan K. Burnham Ana Racoveanu John G. Reynolds Batikan Koroglu Keith R. Coffee Greg L. Klunder 《Propellants, Explosives, Pyrotechnics》2024,49(2):e202300237
We investigate and model the cook-off behavior of 1,3,5-triamino-2,4,6-trinitrobenzene (TATB) to understand the response of explosive systems in abnormal thermal environments. Decomposition has been explored via conventional ODTX (one-dimensional time-to-explosion), PODTX (ODTX with pressure-measurement), PyGC-MS (pyrolysis gas chromatography mass spectrometry), TGA (thermo-gravimetric analysis), DSC (differential scanning calorimetry), and IR (infrared spectroscopy) experiments under isothermal and ramped temperature profiles. The data were used to fit rate parameters for proposed reaction schemes in a MATLAB thermo-chemical computational model. These parameterizations were carried out utilizing a genetic algorithm optimization method on LLNL's high-performance computing clusters, which enabled significant parallelization. These results include a multi-step reaction decomposition model, identification of likely autocatalytic gas-phase species, accurate high-temperature sensitization, and prediction of confined system pressurization. This model will be scalable to several applications involving TATB-based explosives, like LX-17, including thermal safety models of full-scale systems. 相似文献
996.
997.
Dermal uptake directly from air under transient conditions: advances in modeling and comparisons with experimental results for human subjects
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To better understand the dermal exposure pathway, we enhance an existing mechanistic model of transdermal uptake by including skin surface lipids (SSL) and consider the impact of clothing. Addition of SSL increases the overall resistance to uptake of SVOCs from air but also allows for rapid transfer of SVOCs to sinks like clothing or clean air. We test the model by simulating di‐ethyl phthalate (DEP) and di‐n‐butyl phthalate (DnBP) exposures of six bare‐skinned (Weschler et al. 2015, Environ. Health Perspect., 123 , 928) and one clothed participant (Morrison et al. 2016, J. Expo. Sci. Environ. Epidemiol., 26 , 113). The model predicts total uptake values that are consistent with the measured values. For bare‐skinned participants, the model predicts a normalized mass uptake of DEP of 3.1 (μg/m2)/(μg/m3), whereas the experimental results range from 1.0 to 4.3 (μg/m2)/(μg/m3); uptake of DnBP is somewhat overpredicted: 4.6 (μg/m2)/(μg/m3) vs. the experimental range of 0.5–3.2 (μg/m2)/(μg/m3). For the clothed participant, the model predicts higher than observed uptake for both species. Uncertainty in model inputs, including convective mass transfer coefficients, partition coefficients, and diffusion coefficients, could account for overpredictions. Simulations that include transfer of skin oil to clothing improve model predictions. A dynamic model that includes SSL is more sensitive to changes that impact external mass transfer such as putting on and removing clothes and bathing. 相似文献
998.
S Oesterreich SG Hilsenbeck DR Ciocca DC Allred GM Clark GC Chamness CK Osborne SA Fuqua 《Canadian Metallurgical Quarterly》1996,2(7):1199-1206
Heat shock protein 27 (hsp27) belongs to the family of heat shock proteins and is thought to be involved in thermotolerance, cell proliferation, drug resistance, and chaperone processes. The aim of this study was to investigate whether hsp27 levels are correlated with clinical outcome in axillary lymph node-negative breast cancer patients. We describe a Western blot study measuring hsp27 levels in 425 patients and an immunohistochemistry (IHC) study analyzing 788 patients. Results obtained by both methods were concordant. Univariate survival analysis was performed considering hsp27 either as an optimally dichotomized variable or as a continuous variable. Additional data include age at biopsy, tumor size, estrogen receptor (ER) and progesterone receptor status, tumor ploidy and percentage of cells in S phase, and adjuvant therapy. hsp27 levels correlated positively with ER status (P = 0.0001 in Western blot and IHC study), progesterone receptor status (P = 0.0001 in Western blot and IHC study), and aneuploidy (Western blot study, P = 0.0012; IHC study, P = 0.0004) but not with tumor size (Western blot study, P = 0.69; IHC, P = 0.53) or S phase (Western blot study, P = 0.19; IHC study, P = 0.38). Overall, there was no relationship between hsp27 expression and disease-free survival (Western blot study, P = 0.70/0.54; IHC, P = 0.47/0.30) or overall survival (Western blot study, P = 0.16/0.15; IHC, P = 0.46/0.78). Exploratory subset analyses defined by ER status and use of adjuvant treatment indicated that in ER+/untreated patients, high hsp27 levels correlated modestly with shorter disease-free survival (Western blot, P = 0.04/0.04; IHC, P = 0.11/0. 03). hsp27 is not a useful prognostic marker for the clinic in axillary lymph node-negative patients. However, the finding of modest prognostic value of hsp27 in the subgroup of ER+/untreated patients raises new questions about the biological function of hsp27 in breast cancer. 相似文献
999.
The purpose of this exploratory study was to examine issues reported by natural and foster parents when caring for a child 3 years of age or younger with vertically transmitted HIV-disease. Issues common to both groups, and specific to the natural and foster parents were explored. The issues discussed by the natural mothers included guilt, their relationship with their infected child, and the effects of their HIV infection on their family. Issues discussed by foster mothers included their decision to foster a HIV-positive child, characteristics of their HIV- positive foster children, fears of transmission, and the effect of the HIV-positive foster child(ren) on their natural family. Issues common to both sets of mothers include disclosure, support, preparation for the HIV-positive child's death, and life in general. The experiences of these families are important to describe in order for pediatric nurses to give accurate, sensitive, and culturally appropriate care. 相似文献
1000.
The present study was designed to investigate some of the factors that might underlie the commonly found association between agoraphobia and fear of heights (acrophobia). The results showed that measures of acrophobia are highly associated with the tendency to interpret ambiguous bodily sensations as threatening, and with an increased tendency to report bodily sensations of anxiety. These features of acrophobia did not appear to be characteristics found in phobic states in general, nor did measures of acrophobia show any significant relationship to the tendency to interpret external and social stimuli as threatening. These findings suggest that the frequently found co-morbidity between agoraphobia and acrophobia may be linked to cognitive biases in the discrimination and interpretation of bodily sensations that agoraphobia and acrophobia share in common. In addition, the present findings also generate testable hypotheses about the aetiology of acrophobia. 相似文献