bluuebunny/crossref_metadata_2025_split huggingface dataset:
Risk factors for perioperative morbidity and mortality after extended hepatectomy for hepatocellular carcinoma
Authors: Wei A C , Tung-Ping Poon R , Fan S-T , Wong J 
Published: January 2003

Abstract

Background
Extended hepatectomy with resection of more than four segments is a high-risk operation, especially in patients with hepatocellular carcinoma (HCC) associated with chronic liver disease. This study evaluated the risk factors for morbidity and mortality following extended hepatectomy for HCC.

Methods
Preoperative and intraoperative variables of 155 patients who underwent extended hepatectomy for HCC were analysed to identify risk factors for postoperative morbidity and mortality.

Results
The overall morbidity rate was 55·5 per cent (n = 86). Most morbidity was due to ascites or pleural effusion. Significant life-threatening complications occurred in 20·0 per cent (n = 31). The perioperative mortality rate was 8·4 per cent (n = 13). Multivariate analysis found that portal clamping (P = 0·023) and perioperative blood transfusion (P &lt; 0·001) were risk factors for morbidity, whereas perioperative blood transfusion (P &lt; 0·001) was the only risk factor for significant morbidity. Co-morbid illness (P = 0·019) and perioperative blood transfusion (P = 0·004) were risk factors for perioperative mortality.

Conclusion
Meticulous operative techniques to minimize blood loss and transfusion, while avoiding a prolonged Pringle manoeuvre, may help reduce postoperative morbidity. Avoidance of perioperative blood transfusion and careful preoperative selection of patients in terms of overall physiological status are important measures to reduce the postoperative mortality rate.
Surgeons and cognitive processes
Authors: Hall J C , Ellis C , Hamdorf J 
Published: January 2003

Abstract

Background
The surgical mind is geared to make important decisions and perform highly skilled tasks. The aim of this review is to explore the cognitive processes that link these actions.

Methods
The core of this review is derived from a literature search of a computer database (Medline).

Results and conclusion
The surgical image is one of action. However, the effective performance of surgery requires more than mere manual dexterity and it is evident that competent surgeons exhibit the cognitive traits that are held by all experts. The changes that are occurring in surgery indicate a need to place greater emphasis on the cognitive processes that underpin the practice of surgery. It is important that surgeons do not become victims of their own cult image.
A comparison of video-assisted thoracoscopic oesophagectomy and radical lymph node dissection for squamous cell cancer of the oesophagus with open operation
Authors: Osugi H , Takemura M , Higashino M , Takada N , Lee S , Kinoshita H 
Published: January 2003

Abstract

Background
A direct comparison of open operation and video-assisted thoracoscopic surgery (VATS) for radical oesophagectomy has yet to be published.

Methods
Medical records of 149 patients with oesophageal squamous cell carcinoma who underwent oesophagectomy and three-field lymphadenectomy were reviewed. Seventy-seven patients had the thoracic procedure performed via a 5-cm minithoracotomy and four ports (VATS group); the others were operated on by conventional posterolateral thoracotomy (open group).

Results
The mean number of retrieved mediastinal nodes, blood loss and morbidity were similar in the VATS and open groups (33·9 versus 32·8 nodes, 284 versus 310 g, and 32 versus 38 per cent respectively). The thoracic procedure took longer in patients having VATS than in the control group (227 versus 186 min; P = 0·031). Vital capacity reduction was less with VATS than in the open group (15 versus 22 per cent; P = 0·016). The 3- and 5-year survival rates were similar: 70 and 55 per cent respectively for VATS compared with 60 and 57 per cent for the open procedure.

Conclusion
VATS provides comparable results to open radical oesophagectomy, with less surgical trauma.
Individual inflammatory response of human blood monocytes to mesh biomaterials
Authors: Schachtrupp A , Klinge U , Junge K , Rosch R , Bhardwaj R S , Schumpelick V 
Published: January 2003

Abstract

Background
Alloplastic implants such as those employed in hernia repair induce distinct local inflammation and seroma production. As monocytes take a key position in the inflammatory foreign body reaction, their specific release of cytokines was investigated in vitro after incubation with alloplastic materials.

Methods
Human blood monocytes were isolated from buffy coats of 42 healthy blood donors. Cells were cultivated in polystyrene culture wells (4 × 106 cells/well) on polypropylene–polyglactin mesh, on polytetrafluoroethylene, in control wells with the addition of 1 µg lipopolysaccharide (LPS) and on pure polystyrene. Supernatant was taken after 1 h and 5 days, and concentrations of tumour necrosis factor (TNF) α, interleukin (IL) 6 and IL-10 were determined. Donors were defined as ‘high’ or ‘low’ responders when concentrations of TNF-α were above the 75th or below the 25th percentiles, respectively.

Results
In contact with biomaterials, the monocytes liberated TNF-α, IL-6 and IL-10, similar to levels observed after stimulation with LPS. Median cytokine concentrations were not normally distributed and were influenced by donor, timepoint and applied stimulus. One donor matched the criteria for low responder and three for high responder.

Conclusion
The individual was identified as an independent factor for the inflammatory response of monocytes to biomaterials. Moreover, high and low responders could be identified. The variability of cytokine release and the lack of a normal distribution suggest that a larger sample size should be used in future studies of cellular response.
The value of magnetic resonance cholangiopancreatography in predicting common bile duct stones in patients with gallstone disease
Authors: Topal B , Van de Moortel M , Fieuws S , Vanbeckevoort D , Van Steenbergen W , Aerts R , Penninckx F 
Published: January 2003

Abstract

Background
The application of available predictive scoring systems for the detection of common bile duct (CBD) stones has not reduced the number of patients who undergo unnecessary endoscopic retrograde cholangiopancreatography. The aim of this study was to create a predictive model for CBD stones and to assess the value of magnetic resonance cholangiopancreatography (MRCP) in prediction.

Methods
In 1998, 366 patients with gallstone disease (118 males, 248 females; mean age 57 (range 8–84) years) underwent cholecystectomy. Statistical analysis was performed on patient data obtained at the time of first presentation.

Results
CBD stones were demonstrated in 43 (12 per cent) of 366 patients. The predictive model for common duct stones included ultrasonography showing CBD stones or bile duct dilatation, age greater than 60 years, fever, serum alkaline phosphatase level above 670 units/l and serum amylase level above 95 units/l. In patients with a predicted probability greater than 5 per cent, CBD stones were present in 11 per cent, compared with 1 per cent in patients with a probability of 5 per cent or less. MRCP had an observed sensitivity of 95 per cent, specificity of 100 per cent, positive predictive value of 100 per cent and negative predictive value of 98 per cent.

Conclusion
In patients with a predicted probability for CBD stones of more than 5 per cent, MRCP is recommended in order to confirm the presence or absence of stones and as guidance in further management.
Right lobe living donor liver transplantation with or without venovenous bypass
Authors: Fan S T , Yong B H , Lo C M , Liu C L , Wong J 
Published: January 2003

AbstractBackgroundVenovenous bypass was considered necessary to maintain haemodynamic stability and avoid splanchnic and retroperitoneal congestion during the anhepatic phase of liver transplantation. It was essential for right lobe living donor liver transplantation (LDLT) in which the inferior vena cava needed to be cross-clamped to construct wide and short hepatic vein anastomoses. However, many complications related to venovenous bypass have been reported. This study aimed to determine whether venovenous bypass was necessary for right lobe LDLT.MethodsBetween June 1996 and June 2001, 72 patients underwent right lobe LDLT. The outcomes for the first 29 patients who had venovenous bypass during the operation were compared with those of the remaining 43 patients who did not have venovenous bypass. In patients without bypass, blood pressure was maintained during the anhepatic phase by boluses of fluid infusion and vasopressors.ResultsCompared with patients undergoing operation without venovenous bypass, patients who had venovenous bypass required significantly more blood, fresh frozen plasma and platelet infusion, and had a lower body temperature; their postoperative hepatic and renal function in the first week was worse than that in patients who did not have a bypass. The time to tracheal extubation was longer and the incidence of reintubation for ventilatory support was higher with venovenous bypass. Six of the 29 patients with venovenous bypass died in hospital, compared with two of the 43 patients without a bypass (P = 0·05). By multivariate analysis, the lowest body temperature during the transplant operation was the most significant factor that determined hospital death.ConclusionVenovenous bypass is not necessary and is probably harmful to patients undergoing right lobe LDLT, and should therefore be avoided.
Blood oxygenation level dependent functional magnetic resonance imaging
Authors: Mcintyre Michael , Richter Wolfgang , Morden Dara , Wennerberg Anders , Frankenstein Uta 
Published: January 2003

AbstractThe objective of the present article is to provide an introduction to the most widely used method of imaging the functional neuroanatomy of the human brain. The inferential relationship between neural activation and a magnetic resonance signal change is described in detail. The contrast between an active state and a baseline depends on an increased ratio of oxyhemoglobin to deoxyhemoglobin, a longer transverse relaxation time (T), decreased levels of paramagnetically induced dephasing, and a consequently stronger signal in the active state. Issues pertaining to image interpretation, spatial and temporal resolution, and image stability are described. © 2003 Wiley Periodicals, Inc. Concepts Magn Reson 16A: 5–15, 2003
Perfusion‐based functional magnetic resonance imaging
Authors: Silva Afonso C. , Kim Seong‐Gi 
Published: January 2003

AbstractThe measurement of cerebral blood flow (CBF) is a very important way of assessing tissue viability, metabolism, and function. CBF can be measured noninvasively with magnetic resonance imaging (MRI) by using arterial water as a perfusion tracer. Because of the tight coupling between neural activity and CBF, functional MRI (fMRI) techniques are having a large impact in defining regions of the brain that are activated due to specific stimuli. Among the different fMRI techniques, CBF‐based fMRI has the advantages of being specific to tissue signal change, a critical feature for quantitative measurements within and across subjects, and for high‐resolution functional mapping. Unlike the conventional blood oxygenation level dependent (BOLD) technique, the CBF change is an excellent index of the magnitude of neural activity change. Thus, CBF‐based fMRI is the tool of choice for longitudinal functional imaging studies. A review of the principles and theoretical backgrounds of both continuous and pulsed arterial spin labeling methods for measuring CBF is presented, and a general overview of their current applications in the field of functional brain mapping is provided. In particular, examples of the use of CBF‐based fMRI to investigate the fundamental hemodynamic responses induced by neural activity and to determine the signal source of the most commonly used BOLD functional imaging are reviewed. © 2003 Wiley Periodicals, Inc. Concepts Magn Reson 16A: 16–27, 2003
Functional magnetic resonance imaging of the human brain and spinal cord by means of signal enhancement by extravascular protons
Authors: Stroman P.W. , Tomanek B. , Malisza K.L. 
Published: January 2003

AbstractA review of functional magnetic resonance imaging (fMRI) signal changes in spin–echo image data is presented. Spin–echo fMRI data from the human brain and spinal cord show a consistent departure from that expected with blood oxygen level dependent (BOLD) contrast. Studies to investigate this finding demonstrate fMRI signal changes of 2.5% in the spinal cord and 0.7% in the brain at 1.5 T, which is extrapolated to an echo time of zero. Consistent evidence of a non‐BOLD contrast mechanism arising from a proton‐density change at sites of neuronal activation is demonstrated. A mathematical model and physiological explanation for signal enhancement by extravascular protons is also presented. © 2003 Wiley Periodicals, Inc. Concepts Magn Reson 16A: 28–34, 2003
Hardware considerations for functional magnetic resonance imaging
Authors: Silva Afonso C. , Merkle Hellmut 
Published: January 2003

AbstractFunctional magnetic resonance imaging (fMRI) techniques based on changes in blood oxygenation or regional cerebral blood flow or volume have had great impact in mapping the regions of the brain that are activated by specific stimuli. The basic strategy of fMRI paradigms is to acquire data during two different brains states: one state usually comprises a resting condition, while in the other state the subject is performing a specific sensory or cognitive task. The signal difference between the activated and resting signals is on the order of only a few percent, and therefore the reliability and reproducibility with which it can be detected limit both the temporal and spatial resolution of fMRI experiments. The era of fMRI has significantly contributed to advancing the state of the art of MRI scanners. Every hardware component in modern MRI scanners, from the magnet itself to the gradient, shim, and RF coils to peripheral stimulus delivery equipment, has been (re)designed to perform to the limit of currently available technology and to improve the quality of MRI data, particularly fMRI data. The current state of the art of MRI scanners is described in light of their use in fMRI experiments. © 2003 Wiley Periodicals, Inc. Concepts Magn Reson 16A: 35–49, 2003
Peer mediation training and program implementation in elementary schools: Research results
Authors: Bickmore Kathy 
Published: January 2003

AbstractThis research examines the implementation and effects of a peer mediation program in twenty‐eight urban elementary schools. The Center for Conflict Resolution, a program of the Cleveland, Ohio, public schools, provided intensive training and follow‐up support for teams of peer mediators and adult advisers at each school. Trainers were youths from the same community. Qualitative and quantitative evidence indicate that this program significantly improved the average eight‐ to eleven‐year‐old students understanding of and inclination to use nonviolent conflict resolution and his or her capacity to achieve in school. The study outlines the specific commitments from administrators and other staff members that were required to develop and implement equitable, effective, and sustainable programs.
Structural sources of conflict in a university context
Authors: Barsky Allan Edward 
Published: January 2003

AbstractUniversities present an interesting setting for the analysis of conflict because of their unique organizational structures. They combine hierarchical administration with a peer philosophy that views professors as self‐governing colleagues (or a community of scholars), a tenure system for job security, an ethic of academic freedom within a highly regulated and bureaucratized system, decentralized departments that often operate independently rather than as part of an organization, and myriad constituencies served by the university (Baldridge, 1971; Douglas, 1998; Hartman, 1977; Ostan 1995).This ethnographic study has explored experiences of conflict from the perspective of university students, professors—including both tenure‐and non‐tenure‐stream faculty members, administrators, and support staff members. Accordingly, the purposes of this article are to (1) describe the manner in which structural factors lead to the expression of conflict within a university setting and (2) describe the implications of structural sources of conflict, including ways in which universities and other organizations can try to address these sources of conflict.
What mediators do with words: Implementing three models of rational discussion in dispute mediation
Authors: Jacobs Scott , Aakhus Mark 
Published: January 2003

AbstractThis study identifies three models of rationality that mediators employ in interpreting conflict situations and formulating the most sensible and appropriate way to proceed. These models, critical discussion, bargaining, and therapy articulate what mediators presume about the nature of conflict and the framework of activity required to manage the conflict. The models were developed through a close analysis of a corpus of forty‐one mediation sessions. The analysis shows that the substance, direction, and outcome of mediation is shaped by the framework of activity implemented by the mediator. This can be seen by the way in which arguments are deflected and discouraged in bargaining and therapy models. These models suggest that mediation competence can be understood in terms of two issues: which model to implement when and how best to implement any model in a stream of discourse.
Disputing neutrality: A case study of a bias complaint during mediation
Authors: Garcia Angela Cora , Vise Krist , Whitaker Stephen Paul 
Published: January 2003

AbstractResearchers find that some participants in mediation hearings report that the mediator was unfair or biased, but disputants rarely communicate these perceptions to the mediator, and very rarely do they do so during the mediation hearing itself. During data collection for a study of mediation hearings, a videotape of a small‐claims mediation hearing was made in which a disputant did make such an accusation during the hearing. This serendipitous capture of an accusation of bias on videotape enables us to examine how a mediator's actions during the hearing may have contributed to a disputants perception of unfairness. Narrative analysis is used to show how mediation techniques such as empowerment, representation of disputant positions, story summarizing, and emotion work can cause a perception of bias if they are applied unequally.
Discourses in the use and emergence of organizational conflict
Authors: Kusztal Iwona I. 
Published: January 2003

AbstractFour discourses in use were identified in a grounded theory study of organizational conflict. This article discusses how these different discourses in use were involved in the emergence of organizational conflicts. Discourses in use determine what conflicts arise in the organization and how they are understood and managed. In this article, the practical implication of this approach for assessing and managing conflict processes in organizations is considered.
On the circuit paradigm in quantum networks
Authors: Mahler Günter , Otte Alexander , Stollsteimer Marcus 
Published: January 2003

AbstractPhysics is not scale invariant. As we reach the quantum domain not only new computational modes, but also fundamental control limits, are expected to appear. We investigate, to what extent some variant of the circuit paradigm may remain applicable, despite the qualitative change in function. Copyright © 2003 John Wiley & Sons, Ltd.
Decoherence in quantum systems and the network paradigm
Authors: Mathis W. , Pahlke K. , Zou XuBo 
Published: January 2003

AbstractSince quantum systems interact with their environment permanently or within a measurement process, there is much interest in concepts of open quantum system modelling. In this paper we give an overview on three different concepts in order to address this problem in the context of the network paradigm. Furthermore the modelling of spatially localized decoherence processes within the stochastic diffusion wave equation approach of Gisin et al. is briefly discussed. Copyright © 2003 John Wiley & Sons, Ltd.
Solid state coherent quantum dot system for quantum computing and quantum transmission
Authors: Matsueda Hideaki 
Published: January 2003

AbstractRecent progress in nano‐metre structure and measurements is capable of providing us with the freedom to harness fast and seemingly weak correlations between atoms in an ensemble, manifesting them at macroscopic level. So we have investigated a prospective model of solid state integrated circuits for quantum computation, based on our coherence retentive resonance dynamic dipole–dipole interaction (RDDDI) theory. In this model, each qubit is a block consisting of an ensemble of quantum dots, and the energetics of which suggests stability up to room temperature. Here, we propose a qubit swap (∏4) gate applying our RDDDI. Moreover, integration of the ∏4 gate is proposed to form quantum circuits that can transfer a qubit state to any position within them, realizing bit reversal permutation circuits with even and odd bits, and a shuffling circuit. Copyright © 2003 John Wiley & Sons, Ltd.
CrossNets: possible neuromorphic networks based on nanoscale components
Authors: Türel Özgür , Likharev Konstantin 
Published: January 2003

AbstractExtremely dense neuromorphic networks may be based on hybrid 2D arrays of nanoscale components, including molecular latching switches working as adaptive synapses, nanowires as axons and dendrites, and nano‐CMOS circuits serving as neural cell bodies. Possible architectures include ‘free‐growing’ networks that may form topologies very close to those of cerebral cortex, and several species of distributed crossbar‐type networks, ‘CrossNets’ (including notably ‘InBar’ and ‘RandBar’), with better density and speed scaling. Numerical modelling show that the specific signal sign asymmetry used in CrossNets allows self‐excitation of recurrent networks with long‐range cell interaction, without a symmetry‐breaking global latchup. Our next goal is to develop methods of globally supervised teaching of extremely large networks with no external access to individual synapses. Such development would open a way towards cerebral‐cortex‐scale networks (with ∼1010 neural cells and ∼1014 synapses) capable of advanced information processing and self‐evolution at a speed several orders of magnitude higher than their biological prototypes. Copyright © 2003 John Wiley & Sons, Ltd.
Signal processing by pulse‐driven molecular arrays
Authors: Csurgay Árpád I. , Porod Wolfgang , Rakos Balázs 
Published: January 2003

AbstractIn this paper cellular array processors composed of weakly Coulomb coupled molecules are studied. Equivalent circuits for molecules performing optically induced electron and proton transfer are presented, and pulse‐driven computing architectures are proposed. The polymer‐like molecular array is processing signals if it is subjected to a sequence of electromagnetic pulses of well‐defined frequency, envelope and length. Programming is accomplished by selecting proper sequence of pulses. Universality of the proposed architecture for computing is demonstrated. Copyright © 2003 John Wiley & Sons, Ltd.