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991.
Microsystem Technologies - We report an anomalous Stokes shift effect observed in colloidal solutions containing down-shifting Carbon quantum dots (CQDs) of different sizes that is expected to have...  相似文献   
992.
Measurement data are given for the thermal diffusivity of Zr–2.5% Nb and Zr–50% Nb alloys both with the usual polycrystalline structure and with submicro- and nanocrystalline structures at high temperatures, which were determined in the automated mode using the dynamic technique of plane temperature waves.  相似文献   
993.
The transport properties of granular Cd3As2 + MnAs (44.7% MnAs) composite structures have been studied near room temperature at high hydrostatic pressures of up to 9 GPa. The results demonstrate that the composite undergoes a structural phase transition and has a pressure-induced negative magnetoresistance.  相似文献   
994.
In this study, a multistage stochastic programming (SP) model is presented for a variant of single-vehicle routing problem with stochastic demands from a dynamic viewpoint. It is assumed that the actual demand of a customer becomes known only when the customer is visited. This problem falls into the category of SP with endogenous uncertainty and hence, the scenario tree is decision-dependent. Therefore, nonanticipativity of decisions is ensured by conditional constraints making up a large portion of total constraints. Thus, a novel approach is proposed that considerably reduces the problem size without any effect on the solution space. Computational results on some test problems are reported.  相似文献   
995.
996.
Technical Physics Letters - GaAs Schottky barrier detectors for α particle spectrometry have been tested. Detectors had an input window area of 80 mm2 and a working barrier layer thickness of...  相似文献   
997.
With the increasing emphasis on independent learning and early patient contact, the time in the undergraduate medical curriculum for formal teaching of morphology of disease is decreasing. Thus, we thought it advisable to identify those core morphological entities of disease that should not get lost in the new paradigm. Our approach was to list all disease processes in Robbins Pathologic Basis of Diseases, 5th edition, that have distinguishing gross or microscopic characteristics. Appropriate portions of this list of 952 morphological entities from the Robbins textbook were distributed to 46 clinical specialists and pathology faculty. Each of these was asked to strongly agree, agree, disagree, or strongly disagree with the following for each entry on the list: "For purposes of developing concepts of disease, an M2 physician in training should recognize classical examples or a diagrammatic representation of the following lesions, and distinguish them from each other." Responses resulted in a consensus core list of 63 general disease process lesions and 545 organ system lesions, for a total of 608. These 608 core morphological entities were incorporated into our course by means of (1) a computer program with over 1,022 images and clinical-pathological correlations, and (2) a core list of morphological objectives for each unit in the course. In general, entities were judged noncore material if they were rare or were microscopic lesions of primary interest to pathologists and provided no major pathomorphologic concepts. The computer program as a supplement to glass slides and gross specimens has been very well accepted by students, and satisfactory performance on examinations has been maintained in spite of a 25% reduction in pathology course contact hours.  相似文献   
998.
Very large macrophages, which we have termed "giant macrophages" (G-M phi), have been found in renal tubules, some containing cytoplasmic vacuoles. To elucidate their pathophysiological roles, we examined renal biopsy tissues from various primary glomerulonephritis (GN) and tubulointerstitial nephritis (TIN) using immunohistochemistry with monoclonal antibodies against M phi and other cell surface markers. Giant macrophages were absent or rare in TIN, minimal change nephrotic syndrome, and minor glomerular abnormalities, but G-M phi was plentiful in progressive glomerulonephrides such as IgA nephropathy with crescents, membranoproliferative GN, focal segmental glomerulosclerosis, and especially in crescentic GN. These G-M phi were usually seen in the lumen of renal tubules, but occasionally were found in the Bowman's spaces and glomerular tufts, and similar cells were also found in urine. Moreover, they frequently made contact with tubular epithelial cells expressing intercellular adhesion molecule-1, and the tubular epithelial cells in such lesions often had degenerative changes. Giant M phi may damage tubular epithelial cells from the luminal side. Phenotypically, G-M phi showed activated (CD71+) and mature (25F9+) characteristics along with features of M phi (CD68+), and the cytoplasm contained a great deal of lipids. The numbers of G-M phi in renal tissues closely correlated with the degree of hematuria (rho = 0.5, P < 0.001), serum creatinine value (r = 0.63, P < 0.001) in GN patients (N = 96) and with proteinuria in IgA nephropathy patients (r = 0.89, P < 0.001, N = 27). These data suggest that G-M phi are M phi that were activated and matured in certain active inflammatory sites, which flowed into tubules and then into urine. Thus, the existence of G-M phi in biopsy tissue or urine reflect the activity of GN and may have a predictive value for the progression of GN.  相似文献   
999.
To date, the "warm-up" phenomenon in patients has been evaluated by ECG and symptom analysis. We investigated the warm-up phenomenon with supine bicycle stress echocardiography in patients with coronary artery disease documented by angiography and positive stress echocardiography. Sixteen coronary artery disease patients (54 +/- 9 years), who were off treatment throughout the study, were enrolled. Each of them underwent two consecutive exercise tests (25 W/2 min) with a 10-min recovery to reestablish baseline conditions. At the end of each stage of exercise and at peak exercise, when wall motion abnormalities (WMA), 1 mm ST depression and angina occurred, and at each minute, for the first 6 min of recovery, a 12-lead ECG was recorded and rate-pressure product was calculated. Time of onset and duration of 1 mm ST depression, WMA and angina, were also determined. Peak WMA, peak wall motion score index, duration of exercise and severity of angina were also evaluated. Exercise time duration and peak rate-pressure product were greater during the second than the first test (p = 0.02, p = 0.03 respectively); the second test also showed a longer delay of the onset of 1 mm ST depression and WMA (p = 0.01, p = 0.01 respectively) and higher rate--pressure product values (p = 0.04, p = 0.03 respectively). On the contrary, wall motion score index during the first and the second test was similar. Time to angina onset was longer during the second test (p = 0.03); the recovery period of ST depression and WMA was shorter during the second test (p = 0.02). In conclusion, these preliminary data show that patients tolerated the second period of ischemia better than the first, consistent with the presence of the warm-up phenomenon. However, the similarity of values of wall motion score index and WMA did not support a reduction in the ischemic area during the second test. This is in contrast with a possible modification of myocardial metabolism which typically underlies the ischemic preconditioning.  相似文献   
1000.
A 38-year-old woman was transmitted to hospital with profuse vaginal bleeding. The origin of the vaginal injuries (resulting from "normal" sexual intercourse vs. use of instruments for manipulation in the vagina) was obscure. The wound pattern is presented and the literature on the subject is reviewed with special reference to predisposing factors and genesis of coital injuries. Concerning the wound pattern, reflecting a blunt trauma, a manipulation with a (so far unknown) instrument, but also with finger or hand could not be proved with the required certainty. In the presented case the origin of the vaginal injuries from "normal" sexual intercourse as described by the accused man could not be excluded.  相似文献   
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