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361.
Oshrit Hoffer Tatiana Rabin Rony-Reuven Nir Rafael Y. Brzezinski Yair Zimmer Israel Gannot 《Journal of biophotonics》2023,16(1):e202200214
Malignant tumors have high metabolic and perfusion rates, which result in a unique temperature distribution as compared to healthy tissues. Here, we sought to characterize the thermal response of the cervix following brachytherapy in women with advanced cervical carcinoma. Six patients underwent imaging with a thermal camera before a brachytherapy treatment session and after a 7-day follow-up period. A designated algorithm was used to calculate and store the texture parameters of the examined tissues across all time points. We used supervised machine learning classification methods (K Nearest Neighbors and Support Vector Machine) and unsupervised machine learning classification (K-means). Our algorithms demonstrated a 100% detection rate for physiological changes in cervical tumors before and after brachytherapy. Thus, we showed that thermal imaging combined with advanced feature extraction could potentially be used to detect tissue-specific changes in the cervix in response to local brachytherapy for cervical cancer. 相似文献
362.
A high concentration of potassium phosphate (75–100 mM) stabilized pH and supported extensive growth of Streptomyces clavuligerus in a chemically defined medium; such a concentration also inhibited cephalosporin production. Although Tris buffer was found to have detrimental effects on growth and antibiotic production, 3-(N-morpholino)-propane sulfonate (MOPS) or 2-(N-morpholino)-ethane sulfonate (MES) buffer provided a nontoxic buffering system. In the presence of MOPS buffer, cephalosporin production was optimal at 25 mM phosphate, whereas higher concentrations of phosphate progressively inhibited antibiotic production up to 85% without modifying the pH pattern. MOPS buffer can be used to conduct fermentations at a relatively constant pH value in shake flasks.List of Non-Common Abbreviations MOPS
3-(N-morpholino)propane sulfonic acid
- MES
2-(N-morpholino)ethane sulfonic acid 相似文献
363.
Transformation in Bacillus subtilis. A simple direct method 总被引:1,自引:0,他引:1
Summary Transformation may be accomplished by lysing previously prepared donor protoplasts with a suspension of competent recipient cells. Joint transfer of two widely separated markers is obtained with high frequency. 相似文献
364.
Abraham J. Susswein Yair Achituv Mitchell S. Cappell David C. Spray Michael V. L. Bennett 《Journal of comparative physiology. A, Neuroethology, sensory, neural, and behavioral physiology》1984,155(2):209-218
Summary Pharyngeal movements during feeding inNavanax inermis were filmed and correlated with known neural activity controlling the pharynx. Seven distinct components of feeding were identified. Occurrence of a component was in some cases fixed, in that once initiated the act went to completion, and in other cases reflex, in that tonic stimulus control was needed for the act to be maintained. As few as 2 or as many as 7 different motor acts could occur in a feeding sequence. The specific acts which make up a sequence were dependent upon the nature of the prey stimuli that elicited feeding: qualitatively as well as quantitatively different feeding sequences were elicited by prey of differing sizes or by prey which was withdrawn fromNavanax at different stages in a movement. The data indicate that the sequence of pharyngeal movements is not preprogrammed, but rather the sequence is appropriate to a specific type of prey. Flexibility in fitting a feeding sequence to the prey that elicits the sequence is achieved by combining in different ways a limited number of specific, fairly stereotyped motor acts. 相似文献
365.
A temperature sensitive mutant in Bacillus subtilis with an altered elongation factor G 总被引:6,自引:0,他引:6
Summary A temperature sensitive mutant of Bacillus subtilis with an altered elongation factor G is described. The mutation is highly co-transformable with resistance to fusidic acid.This work is part of a Ph. D. Thesis to be submitted to Tel Aviv University. 相似文献
366.
Little attention has been directed to the study of soil flow and the complex relationships among energy water and soil flow in terrestrial ecosystems. Soil plays an important role in arid ecosystems. After water soil is the second key factor in the development of an arid ecosystem since soil is the only part of the system capable of absorbing and storing water and nutrients during the hot and long summer period. The present work presents a case study of an ecological soil flow chain in an arid environment and analyses the relationship between this chain and the energy and water flow chains. The study was conducted at the Sde Boqer experiment site located in the northern Negev of Israel where average annual rainfall is 92 mn. Data collected during five consecutive years show that the soil movement process within the ecosystem studied cannot be considered as a purely physical phenomenon, but rather as a part of a complex system in which the burrowing and digging activity of Isopods and Porcupines plays an important role by providing disaggregated soil particles easy to remove by shallow flows. Although controlled by the spatial distribution of soil moisture the biological activity acts as a regulator of soil depth and thus of soil moisture. If this regulating role is deleted from the system a new ecosystem, more arid, can be expected to develop. It is therefore concluded that the study of state and flow variables of an arid ecosystem should consider altogether the water, soil, energy and mineral chains. 相似文献