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The authors report on their experience about urinary cytology in 1991. They studied 100 patients with cytology and histology, carried by cystoscopy and cold-mapping biopsy, trying to have notice about cytological value and proficiency.  相似文献   
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In this paper we deal with some finite-time control problems for discrete-time, time-varying linear systems. First we provide necessary and sufficient conditions for finite-time stability; these conditions require either the computation of the state transition matrix of the system or the solution of a certain difference Lyapunov inequality. Then we address the design problem. The proposed conditions allow us to find output feedback controllers which stabilize the closed loop system in the finite-time sense; all these conditions can be expressed in terms of LMIs and therefore are numerically tractable, as shown in the example included in the paper.  相似文献   
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The biocompatibility of titania/hydroxyapatite (TiO2HA) composite coatings, at different ratio obtained by sol–gel process, was investigated studying the behavior of primary cultures of rat osteoblastic cells, isolated by femoral trabecular bone tissue. Moreover, the results have been compared with the response of human osteoblast-like MG63 cell line. Cytotoxicity of coatings was assessed by lactate dehydrogenase activity (LDH). The cellular behavior was analyzed by the cell proliferation (MTT test), cell morphology (SEM) and the biochemical markers evaluation of osteoblastic phenotype, such as alkaline phosphatase activity (ALP) and osteocalcin production. The results showed that TiO2/HA coatings have no toxic effects and seemed to be a good support for cell adhesion and proliferation. Moreover, these materials allowed the differentiation of osteoblasts, stimulating the expression of alkaline phosphatase activity. The responses of the primary rat osteoblasts and human osteoblast-like MG63 cell line grown onto these coatings were similar in terms of proliferation and ALP activity. Differences were found considering the osteocalcin production. The results show that these coatings, thanks to their chemical composition and the deposition technique, are very promising for the potential orthopedic and dental applications.  相似文献   
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To evaluate the efficacy of continuous administration of 50% nitrous oxide in oxygen for reducing pain during flexible fiberoptic bronchoscopy 32 children aged 3-60 months were randomly assigned to an experimental or a control group. Indications for endoscopy included persistent atelectasis (6), wheezing (10) cystic fibrosis (2) pneumonia (11) persistent cough (3). All patients received Midazolam (0.3 mg/kg) atropine (20 mcg/kg) intra rectaly 20 minutes before the procedure. The flexible fiberoptic bronchoscope (Olympus BF3C4) was inserted transnasally through a face mask. Topical anesthesia with 1% lidocaine hydrochloride (3 mg/kg) was applied to the nose, larynx, trachea and bronchial tree over 15 minutes through the suction chanel of the bronchoscope. All patients were monitored with a pulse oximeter and a cardiac monitor. The experimental group (n = 16) received 50% nitrous oxide in oxygen prior (3 minutes) and during flexible fiberoptic bronchoscopy, the control group (n = 16) received only oxygen. We measured pain of the children by a behavioral observation scale (Children's Hospital of Eastern Ontario Pain Scale: CHEOPS) at each phase of topical anesthesia during bronchoscopy in the two groups. At the end of bronchoscopy physician's satisfaction was scored by a visual analogue scale (VAS 0-100) in which 0 corresponded to absence of satisfaction. Nitrous oxide was associated with lesser pain scores than those with oxygen. Physician significantly preferred these procedure compared with oxygen. No complication occurred during procedure. Combined with local anesthesia midazolam and atropin the administration of 50% nitrous oxide in oxygen seems a better choice for flexible fiberoptic bronchoscopy in children and should be used routinely.  相似文献   
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This paper presents a comparative analysis of the performances of both a traditional induction meter and various types of commercial static meters for reactive energy in the presence of harmonic distortion. This is a topical issue, since there are several types of static meters on the market, based on different principles of construction. In accordance with current standards, these meters are designed to operate in sinusoidal conditions and their performance is not tested in the presence of harmonic distortion. However, with the increase of pollution levels in power systems, the meters may be used even in the presence of distorted voltages and/or currents; in such cases, their accuracy may be very different from the nominal conditions, and the various meters may lead to different measurements of energy for the same load conditions. In this paper, the analysis is supported by several experimental tests, performed by means of a power calibrator.  相似文献   
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The spectrum modification technique is a digital procedure for placing the spectrum of any band-limited signal-analog or digital within an arbitrarily chosen set of (nonoverlapping) frequency intervals, the sum of whose lengths is not less than the original bandwidth of the signal. Because it can serve the function of several digital techniques, such as mixing, interpolating, and decimating, and can he realized in a finite impulse response (FIR) filter form, it may be suitably implemented by a programmable FIR filter having a flexible timing scheme. The technique is more computationally efficient for many of its applications than the conventional algorithms it replaces. In the application for which it was developed, it replaced a mixer and the concomitant filtering required to shift a signal spectrum a fraction of its bandwidth and cut the computational rate an order of magnitude.  相似文献   
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This paper is focused on the use of data acquisition boards (DAQs) for the development of high accuracy PC-based instruments for the measurements of electrical power. The proposed systems are simple, portable and low cost because they are based on commercial data acquisition boards (DAQs) connected to a common personal computer. Data processing is carried out by a commercial software based on an interpolating windowed FFT. In the paper it is shown how the voltage can be sensed directly, thanks to the DAQ input range, thus avoiding expensive voltage dividers. The set up of the DAQs-based solutions is described and the evaluation of their metrological features is made by means of a comparison with the Italian power primary standard, which was built at INRIM with a complex solution and expensive with two high precision digital voltmeters.  相似文献   
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This paper presents a single-point method for the identification of prevailing disturbing loads in power systems for both single-phase and three-phase applications downstream or upstream from the metering section. It is based on the simultaneous measurement of three nonactive power quantities, which are based on the IEEE Std. 1459-2000 approach. The proposed method is only based on the separation of the fundamental components from the harmonic content of voltage and current; thus, it does not require any spectral analysis of the voltages and current. In this paper, the formulation of the proposed method and its time-domain implementation are described; moreover, some simulation results are presented and discussed, showing the effectiveness of the method both in the absence and in the presence of the measurement transducers.  相似文献   
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