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1.
JL Lagrange JL Fischel S Galliani P Formento T Guillot M Bardon G Milano 《Canadian Metallurgical Quarterly》1993,(11):1531-1535
The objective of the present in vitro study was to determine an optimal timing of the irradiation in the combination cisplatin (CDDP) and 5-fluorouracil-folinic-acid (5-FU-FA) allowing a maximal cytotoxic effect on a human cell line derived from a head and neck carcinoma (CAL 27 cells). The various tested chemoradiotherapy sequences were applied in parallel to human keratinocytes in culture (SVK 14 cells). This was done in order to define the best sequence allowing the achievement of an optimal selectivity of the cytotoxic effects. The drug sequence was: CDDP over 2 h then fresh medium was added including the tandem 5-FU-d,I FA applied 6 h after CDDP, for 5 days. Irradiation was applied only once and at various times within the drug sequence. The cytotoxicity effects of the different chemoradiotherapy combinations were assessed by the MTT semi-automated test. The part taken by the 5-FU-FA combinations in the overall cytotoxicity was examined; an effect was apparent on CAL 27 cells only. The evolution of the radiation effect (RE = cell survival after drugs/cell survival after drugs plus irradiation) was analysed as a function of the different times of irradiation within the given drug sequence. Clearly, the RE values were dependent upon time at which the radiation dose in the chemoradiotherapy regimen was administered. For CAL 27 cells, irradiation effects were maximal at the first irradiation time tested after the end of the CDDP exposure (i.e. t = 3.5 h). In contrast, this optimal chemoradiotherapy timing for better cytotoxicity on CAL 27 cells did not correspond to that of SVK 14 cells. Consequently, it was possible to establish that the best time for the selectivity index was located shortly after the CDDP exposure. 相似文献
2.
Morphology, histology, and immunohistochemistry of the adrenocortical and adrenomedullary homologs (adrenal glands) of the following developing and adult teleosts were examined: Salmoniformes-Oncorhynchus mykiss (rainbow trout), Salmo trutta fario (brown trout), Coregonus lavaretus (white fish); Cyprinodontiformes-Gambusia affinis (mosquito fish). Perciformes-Dicentrarchus labrax (sea bass), Sparus aurata (sea bream), Diplodus sargus (white bream), Oblada melanura (saddled bream). The anatomical relationships of the gland with the renal system and venous vessels were also noted. In adults of all species steroidogenic and catecholaminergic chromaffin cells were found in the head kidney, which is pronephric in origin and subsequently transformed into a hematopoietic lymphatic organ. In Perciformes, chromaffin cells are distributed around the anterior and posterior cardinal veins and ducts of Cuvier; in Salmoniformes, around the posterior cardinal veins and in the hematopoietic tissue; and in G. affinis, around the ducts of Cuvier and posterior cardinal veins, while a few are visible also around the sinus venosus. In Perciformes and Salmoniformes, numerous chromaffin cells are also present in the posterior kidney, derived from the opisthonephros, in contact with the caudal vein. Steroidogenic cells are always confined to the head kidney. During development chromaffin and steroidogenic cells appear early after hatching in the pronephric kidney, at the level of the ducts of Cuvier and of the cephalic part of the posterior cardinal veins. Later, chromaffin cells in Perciformes reach the anterior cardinal veins, and subsequently, in both Perciformes and Salmoniformes, they reach the developing posterior kidney. Their localization along the posterior kidney is still in progress about 4 months after hatching and is completed about a year after hatching. These findings support the concept that the structure of the adrenal gland in teleosts is intermediate between that of the other actinopterygians and that of tetrapods. The development differs from that of tetrapods in that it occurs mainly in the pronephros and only later do chromaffin cells reach the opisthonephric kidney. 相似文献
3.
In this paper, we describe a pervasive game, Blowtooth, in which players use their mobile phones to hide virtual drugs on nearby airline passengers in real airport check-in queues. After passing through airport security, the player must find and recover their drugs from the innocent bystanders, without them ever realising they were involved in the game. The game explores the nature of pervasive game playing in environments that are not, generally, regarded as playful or “fun”. This paper describes the game’s design and implementation as well as an evaluation conducted with participants in real airports. It explores the players’ reactions to the game through questionnaire responses and in-game activity. The technologies used in Blowtooth are, intentionally, simple in order for the enjoyment of the game to be reliant more on the physical environment rather than the enabling technologies. We conclude that situating pervasive games in unexpected and challenging environments, such as international airports, may provide interesting and unique gaming experiences for players. In addition, we argue that pervasive games benefit most from using the specific features and nature of interesting real-world environments rather than focusing on the enabling technologies. 相似文献
4.
We discuss the application of digital systems to the automatic control of dual-wave optical interferometers. We show that, if the mechanical-modulation technique is used for error-signal extraction, digital techniques can be used both for error-signal extraction and for control-signal generation. Therefore, apart from two front/end amplifiers that are necessary to match the dynamics of the detectors and actuators to the dynamics of the analog-to-digital converters and digital-to-analog converters, no other analog devices are required. In particular, the mechanical-modulation technique requires the synchronous demodulation of the photodiode output signal. Hence we need to implement a digital lock-in amplifier whose algorithm is described here. Finally, we describe one of the possible applications of this digital control procedure, such as the control of a classic Mach-Zehnder interferometer in air. 相似文献
5.
Just a few years ago it was generally believed that the NMR properties of superfluid3He far below Tc would not be qualitatively different from those found at higher temperatures. Surprisingly, the strange enhancement of relaxation processes at around 0.4 Tc named catastrophic relaxation, was then found. Recently an extremely long lived induction signal with new dynamical properties was discovered in the region of 100 K. Some of the newly discovered properties can be partly explained, although there are still many unsolved problems. The main aim of this article is to raise new questions for future investigations at the lowest temperatures presently possible. 相似文献
6.
The study population consisted of ninety patients between the ages of 22 and 64 years. All had mild or moderate hypertension at rest and were subjected to exercise tests using a cycloergometer. The sex ratio for the patients was 0.875. Blood pressure and heart rate were recorded at three time points, at three minute intervals. The initial load was thirty watts for men and 25 watts for the women. A graph of changes in blood pressure with exercise was produced for each type of antihypertensive drug or combination of drugs. At least nine patients were treated with each type of drug or combination, and blood pressure and heart rate were recorded during exercise to produce the exercise blood pressure profile. Healthy adults generate curves that lie between Y'1 = 0.5X + 108.43 and Y"1 = 0.34X + 83.95 [2]. Any patient generating a curve lying between these two limits was regarded as having a normal exercise blood pressure profile. This study identified two groups of hypertension treatments with respect to exercise blood pressure profile. Abnormal exercise blood pressure profiles were obtained with treatments involving inhibition of calcium receptor activity, diuretics and central antihypertensive drugs. Normal exercise blood pressure profiles were obtained with treatments involving the inhibition of adrenoreceptor activity, alone or in conjunction with a diuretic, and with combined central antihypertensive drug and diuretic treatment. 相似文献
7.
Yannis Ioannidis Diego Milano Hans-Jörg Schek Heiko Schuldt 《International Journal on Digital Libraries》2008,9(2):101-114
DelosDLMS is a novel digital library management system (DLMS) that has been developed as an integration effort within the
DELOS Network of Excellence, a European Commission initiative funded under its fifth and sixth framework programs. In this
paper, we describe DelosDLMS that takes into account the recommendations of several activities that were initiated by DELOS
including the DELOS vision for digital libraries (DLs). A key aspect of DelosDLMS is its novel generic infrastructure that
allows the generation of digital library systems out of a set of basic system services and DL services in a modular and extensible
way. DL services like feature extraction, visualization, intelligent browsing, media-type-specific indexing, support for multilinguality,
relevance feedback and many others can easily be incorporated or replaced. A further key aspect of DelosDLMS is its robustness
against failures and its scalability for large collections and many parallel user requests. We discuss the current status
of an effort to build DelosDLMS, a Digital Library Management System that integrates in various ways several components developed
by DELOS members and showcases a great variety of functionality that is outlined as part of the DELOS vision. 相似文献
8.
Shaun C. Hendy 《Journal of Engineering Mathematics》2005,52(1-3):137-146
A theory of granular plasticity based on the time-averaged rigid-plastic flow equations is presented. Slow granular flows
in hoppers are often modeled as rigid-plastic flows with frictional yield conditions. However, such constitutive relations
lead to systems of partial differential equations that are ill-posed: they possess instabilities in the short-wavelength limit.
In addition, features of these flows clearly depend on microstructure in a way not modeled by such continuum models. Here
an attempt is made to address both short-comings by splitting variables into ‘fluctuating’ plus ‘average’ parts and time-averaging
the rigid-plastic flow equations to produce effective equations which depend on the ‘average’ variables and variances of the
‘fluctuating’ variables. Microstructural physics can be introduced by appealing to the kinetic theory of inelastic hard-spheres
to develop a constitutive relation for the new ‘fluctuating’ variables. The equations can then be closed by a suitable consitutive
equation, requiring that this system of equations be stable in the short-wavelength limit. In this way a granular length-scale
is introduced to the rigid-plastic flow equations. 相似文献
9.
Cannon JW Stoll JA Selha SD Dupont PE Howe RD Torchiana DF 《IEEE transactions on robotics and automation》2003,19(5):912-917
Properly selected port sites for robot-assisted coronary artery bypass graft (CABG) improve the efficiency and quality of these procedures. In clinical practice, surgeons select port locations using external anatomic landmarks to estimate a patient's internal anatomy. This paper proposes an automated approach to port selection based on a preoperative image of the patient, thus avoiding the need to estimate internal anatomy. Using this image as input, port sites are chosen from a grid of surgeon-approved options by defining a performance measure for each possible port triad. This measure seeks to minimize the weighted squared deviation of the instrument and endoscope angles from their optimal orientations at each internal surgical site. This performance measure proves insensitive to perturbations in both its weighting factors and moderate intraoperative displacements of the patient's internal anatomy. A validation study of this port site selection was performed. cardiac algorithm also Six surgeons dissected model vessels using the port triad selected by this algorithm with performance compared to dissection using a surgeon-selected port triad and a port triad template described by Tabaie et al., 1999. With the algorithm-selected ports, dissection speed increased by up to 43% (p = 0.046) with less overall vessel trauma. Thus, this algorithmic approach to port site selection has important clinical implications for robot-assisted CABG which warrant further investigation. 相似文献
10.
Dr. Yuhe R. Yang Dr. Jinglin Fu Shaun Wootten Dr. Xiaodong Qi Dr. Minghui Liu Dr. Hao Yan Dr. Yan Liu 《Chembiochem : a European journal of chemical biology》2018,19(3):212-216
In living cells, compartmentalized or membrane‐associated enzymes are often assembled into large networks to cooperatively catalyze cascade reaction pathways essential for cellular metabolism. Here, we report the assembly of an artificial 2D enzyme network of two cascade enzymes—glucose‐6‐phosphate dehydrogenase (G6PDH) and lactate dehydrogenase (LDH)—on a wireframe DNA origami template. Swinging arms were used to facilitate the transport of the redox intermediate of NAD+/NADH between enzyme pairs on the array. The assemblies of 2D enzyme networks were characterized by gel electrophoresis and visualized by atomic force microscopy (AFM). The spatial arrangements of multiple enzyme pairs were optimized to facilitate efficient substrate channeling by exploiting the programmability of DNA origami to manipulate the key parameters of swinging arm length and stoichiometry. Compared with a single enzyme pair, the 2D organized enzyme systems exhibited higher reaction efficiency due to the promoted transfer of intermediates within the network. 相似文献