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71.
Paravertebral catheters were placed bilaterally through a Tuohy needle under direct video control in a patient undergoing video-assisted thoracoscopic (VAT) surgery for recurrent, bilateral pneumothoraces. Postoperative analgesia was produced by infusing bupivacaine through the catheters. This provided good analgesia. VAT placement of paravertebral catheters is easily accomplished and may be a part of the surgical procedure. 相似文献
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Yau S.S. Nicholl R.A. Tsai J.J.-P. Liu S.-S. 《IEEE transactions on pattern analysis and machine intelligence》1988,14(8):1128-1144
An integrated life-cycle model is presented for use in a software maintenance environment. The model represents information about the development and maintenance of software systems, emphasizing relationships between different phases of the software life cycle. It provides the basis for automated tools to assist maintenance personnel in making changes to existing software systems. The model is independent of particular specification, design, and programming languages because it represents only certain `basic' semantic properties of software systems: control flow, data flow, and data structure. The software development processes by which one phase of the software life cycle is derived from another are represented by graph rewriting rules, which indicate how various components of a software system have been implemented. This approach permits analysis of the basic properties of a software system throughout the software life cycle. Examples are given to illustrate the integrated software life-cycle model during evolution 相似文献
74.
B Gliozzo CK Sung P Scalia V Papa F Frasca L Sciacca F Giorgino G Milazzo ID Goldfine R Vigneri V Pezzino 《Canadian Metallurgical Quarterly》1998,70(2):268-280
The projections of enteric neurons to the circular muscle of the guinea pig gastric corpus were investigated systematically by using the retrogradely transported fluorescent carbocyanine dye 1,1'-didodecyl-3,3,3',3'-tetramethyl indocarbocyanine perchlorate (DiI), applied to the muscle layer or myenteric plexus in vitro. DiI-labeled motor neuron cell bodies were located up to 6.3 mm aboral, 17 mm oral, and up to 20 mm circumferential to the DiI application site. Labeled nerve fibers ran for long distances from the DiI application site toward the greater and lesser curvatures, where they coursed parallel to the bundles of the "gastric sling" muscle. The majority of labeled cells were located toward the lesser curvature of the stomach. Nerve cell bodies that were aboral to the DiI application site were usually small, immunoreactive for choline acetyltransferase, and, thus, were likely to be excitatory motor neurons. Neurons that were located orally were larger, fewer in number, and immunoreactive for nitric oxide synthase and, thus, were likely to be inhibitory motor neurons. Application of DiI directly to the myenteric plexus filled neurons up to 15 mm aborally and up to 21 mm orally but labeled few neurons circumferentially. All nerve cells that were filled from either the circular muscle or the myenteric plexus had Dogiel type I morphological features. These results demonstrate a clear polarity of projection of inhibitory and excitatory motor neurons and a functionally continuous innervation of the circular and gastric sling muscle layers. Nonmotor neurons in the myenteric plexus were demonstrated, but neurons with Dogiel type II morphological features are apparently absent. 相似文献
75.
Hatice?KizginEmail authorView authors OrcID profile Ahmad?Jamal Bidit?Lal?Dey Nripendra?P.?Rana 《Information Systems Frontiers》2018,20(3):503-514
Social media has emerged as a significant and effective means of assisting and endorsing activities and communications among peers, consumers and organizations that outdo the restrictions of time and space. While the previous studies acknowledge the role of agents of culture change, it largely remains silent on the role of social media in influencing acculturation outcomes and consumption choices. This study uses self-administered questionnaire to collect data from 514 Turkish-Dutch respondents and examines how their use of social media affects their acculturation and consumption choices. This research makes a significant contribution to consumer acculturation research by showing that social media is a vital means of culture change and a driver of acculturation strategies and consumption choices. This study is the first to investigate the role of social media as an agent of culture change in terms of how it impacts acculturation and consumption. The paper discusses implications for theory development and for practice. 相似文献
76.
Fengqing?Liu Jaume?ComellasEmail authorView authors OrcID profile 《Photonic Network Communications》2017,33(3):334-347
A precise alignment between point-to-point free space optical (FSO) networks is crucial in order to maximize the performance of data transmission. A sway or low-frequency vibration of FSO base station can affect line-of-sight quality and hence may lead to the occurrence of higher BER. Therefore, the work presented in this paper is to demonstrate an improved auto-alignment single-channel FSO transmission system at X-axis detection area. The receiver base station was fed with pulsed signal laser from a tunable laser source with a central wavelength of 1550 nm. The detection mechanism responds from an analog input signal received that corresponds to the X-axis direction of transmitter vibration. The detection performance of the system was observed by using two approaches: auto-searching of artificial intelligence (AI) detection with stop command and without stop command. The obtained results indicate that the bit sequence of the pulsed signal has low loss by implementing the auto-searching of AI detection with stop command features and hence improves the efficiency of the overall FSO transmission system. 相似文献
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DG Lambie JW Paxon RN Nanda RH Johnson JG Ratcliffee ID Melville GD Morrice 《Canadian Metallurgical Quarterly》1976,21(2):93-94
Using Wistar stain male rats, it has been shown that 2 atmospheric pressures associated with oxygen saturation, together or singly for 90 minutes daily for successive 46 days, resulted in no significant change on the ratio of testes to body weight. No significant change was observed in the incorporation of 3H-thymidine into testes and pituitary glands between the pressure-treated groups and the control group. 相似文献
80.
The acute intravenous toxicity of tedisamil, a new potassium channel blocker, was assessed by infusing it at various rates (1.5 to 10 mg/kg/min.) to ventilated or spontaneously breathing rats subjected to blockade of their peripheral somatic and autonomic nervous systems. The lethal doses for ventilated rats (including pithed animals) were 2-3 times higher than those for spontaneously breathing animals. In spontaneously breathing rats death appeared to be due to respiratory depression which was possibly of central origin since the lethality of tedisamil was not markedly altered by vagotomy, bilateral carotid artery ligation, nor by autonomic nervous system blockade. On the other hand, in all of the artificially ventilated groups, death occurred at higher doses and was related to direct cardiac actions, possibly involving blockade of cardiac potassium and sodium channels. The cardiovascular responses to infusions of tedisamil included tachyarrhythmias, bradycardia, blood pressure changes, increased QRS width and Q-T interval duration. Arrhythmias occurred at sublethal doses and were eliminated by autonomic blockade and pithing. However, the bradycardia, ECG and blood pressure changes induced by tedisamil infusions were unaltered by the various treatments. Thus tedisamil may induce arrhythmias by actions on the autonomic system. 相似文献