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81.
82.
The detection of qualitative differences between the myofibrillar proteins of muscles, which superficial examination would classify as similar on the basis of their ‘redness’ or ‘whiteness’, emphasises the need for more subtle criteria for understanding meat quality. 相似文献
83.
The distribution of chemical bonds in polyisobutene results in a theoretically zero optical and electrical anisotropy of the polymer according to bond polarizability additivity principles as conventionally applied, irrespective of polymer chain conformation. Non-zero values of the segmental anisotropy (~4.4 × 10?40 C2m2/J) derived from strain-optical birefringence on the polymer in the rubbery state have been recently reported by Liberman et al. who suggest qualitatively that severe crowding of the chemical groups in the polymer affects the anisotropies of the group polarizabilities and gives the observed non-zero segmental anisotropy. We have measured optical, electrical and magnetic anisotropies for the pure liquid polymer using techniques of flow birefringence, depolarized light scattering, electro-optic birefringence and magneto-optic birefringence. Segmental optical anisotropies so derived agree with those measured by Liberman et al. and results of the above measurements taken as a whole lead to an origin for the observed anisotropy which requires locality dependent values of optical and electrical bond polarizability anisotropies to be used in the calculation of the polyisobutene polarizability anisotropy. Our explanation of the polarizability locality dependence differs from the steric overlap suggestion of Liberman et al. and depends upon the electric field interaction between dipoles induced in polarizable bonds. 相似文献
84.
Gray scale B-scans in renal sinus lipomatosis show a variety of features which must be differentiated from clinically significant pathological processes. Normal kidneys show dense homogeneous central echoes. In renal sinus lipomatosis, however, the central echoes are divided and become more sparse (Type I), interspersed with small relatively echo-free areas (Type II), or outline a single relatively echo-free area resembling a mass (Type III). In contrast to similar features in hydronephrosis or multiple cysts, the relatively echo-free areas in lipomatosis are ill-defined and do present several weak internal echoes. 相似文献
85.
Chromosome analysis of lymphocytes from the peripheral blood of 20 patients with sarcoidosis and 10 healthy controls showed a significantly greater number of hypomodal cells among the patients. Two patients receiving systemic treatment with glucocorticoids had many chromosomal aberrations. 相似文献
86.
I. Champion P. Dubois‐Fernandez D. Guyon M. Cottrel 《International journal of remote sensing》2013,34(6):1795-1800
Data on forest variables are required for environmental and forest management applications. Numerous authors have shown significant correlations between mean radar response intensity and forest variables (age, height or biomass) but few studies have explored the spatial characteristics of the radar response for varying forest states. In this Letter, variation in the most commonly used texture features is shown as a function of an indicator of forest growth (age) for a controlled homogeneous test site (monospecific, even‐aged forest, with identical sylvicultural practices and a sampling that covers all forest stages from sowing to harvest). Significant linear relationships between some texture features and stand age are observed. Moreover, the quality of some fits indicates that texture could be used instead of the usual intensity–age relationships that saturate for mature stands. 相似文献
87.
Atef Rebhi Thabet Makhlouf Yannick Champion Jean-Philippe Couzinié Nabil Njah 《Journal of Materials Science》2011,46(7):2185-2193
Microstructure evolution of 99.1% aluminum after equal-channel angular extrusion (ECAE) and subsequent heat-treatment was
investigated. After deformation the samples were annealed at different temperatures. The deformed and annealed states were
characterized by Transmission Electron Microscopy (TEM), X-ray diffraction (XRD), and microhardness tests. It was shown that
the observed microstructure changes during subsequent annealing have to be associated with recovery and cells formation. The
initial stages of recovery were investigated using weak-beam technique. The microstructure obtained after annealing for 1 h
at 100 °C consists of some arrangements of the dislocations into sub-grain boundaries within the wide preexisting grains.
Annealing at 300 °C led to the appearance of a duplex microstructure consisting of bands of slightly coarsened grains associated
with refined grains. No growth of dislocation cells was observed up to 400 °C. In XRD measurements, the lattice parameter
increase with subsequent heating. This indicates a continuous grain growth during annealing. This is due to the important
increase of coherency length, D observed parallel to a substantial decrease of rms-strain, ε. 相似文献
88.
DA Alexander AA Naji SB Pinion J Mollison HC Kitchener DE Parkin DR Abramovich IT Russell 《Canadian Metallurgical Quarterly》1996,312(7026):280-284
OBJECTIVE: To compare in psychiatric and psychosocial terms the outcome of hysterectomy and endometrial ablation for the treatment of dysfunctional uterine bleeding. DESIGN: Prospective randomised controlled trial. SETTING--Obstetrics and gynaecology department of a large teaching hospital. SUBJECTS: 204 women with dysfunctional bleeding for whom hysterectomy would have been the preferred treatment were recruited over 24 months and randomly allocated to hysterectomy (99 women) or to hysteroscopic surgery (transcervical resection (52 women) or laser ablation (53 women). MAIN OUTCOME MEASURES: Mental state, martial relationship, psychosocial and sexual adjustment in assessments conducted before the operation and one month, six months, and 12 months later. RESULTS: Both treatments significantly reduced the anxiety and depression present before the operation, and there were no differences in mental health between the groups at 12 months. Hysterectomy did not lead to postoperative psychiatric illness. Sexual interest after the operation did not vary with treatment. Overall, 46 out of 185 (25%) women reported a loss sexual interest and 50 out of 185 (27%) reported increased sexual interest. Marital relationships were unaffected by surgery. Personality and duration of dysfunctional uterine bleeding played no significant part in determining outcome. CONCLUSIONS: Hysteroscopic surgery and hysterectomy have a similar effect on psychiatric and psychosocial outcomes. There is no evidence that hysterectomy leads to postoperative psychiatric illness. 相似文献
89.
90.