bluuebunny/crossref_metadata_2025_split huggingface dataset:
Analysis of high‐field RF coils using the method of lines
Authors: Bodganov Gene , Ludwig Reinhold 
Published: January 2003

AbstractThe method of lines is described as a novel and powerful way to analyze radio frequency (RF) coils for high‐field magnetic resonance imaging. Originally developed for optical and microwave circuits, this method enables a full‐wave solution to Maxwell's field equations without the computational burden of pure finite element or finite difference methods. Because only two of the three geometric dimensions are discretized, while seeking an analytic solution in the remaining space dimension, an efficient solution can be obtained at reasonable geometric restrictions. After outlining the theoretical formulation and the computer implementation of this technique, we will apply it to the modeling of microstrip RF transverse electromagnetic resonator coils at 200 and 400 MHz as well as a high‐pass shielded birdcage resonator and a single‐loop surface coil. With single‐frequency solutions obtainable within 5–10 s on a personal computer, the approach proves highly suitable as a design tool and for rapid prototyping. © 2003 Wiley Periodicals, Inc. Concepts Magn Reson Part B (Magn Reson Engineering) 16B: 22–37, 2003
Complexity theory and models for social networks
Authors: Skvoretz John 
Published: January 2003

AbstractMuch work in complexity theory employs agent‐based models in simulations of systems of multiple agents. Agent interaction follows some standard types of network topologies. My aim is to assess how recent advances in the statistical modeling of social networks may contribute to agent‐based modeling traditions, specifically, by providing structural characterizations of a variety of network topologies. I illustrate the points by reference to a computational model for the evolution of cooperation among agents embedded in neighborhoods and by reference to complex, real social networks defined by the ties of political support between US Senators as revealed through ties of cosponsorship of legislation. © 2003 Wiley Periodicals, Inc.
Gray‐scale and color Doppler findings in bilateral internal jugular vein thrombosis caused by anaplastic carcinoma of the thyroid
Authors: Panzironi Giuseppe , Rainaldi Roberto , Ricci Francesca , Casale Alessandra , Macciucca Marina De Vargas 
Published: January 2003

AbstractBilateral internal jugular vein thrombosis is a rare complication of thyroid cancer. The most common manifestation of this condition is superior vena cava syndrome. We report the sonographic findings in a case of bilateral internal jugular vein thrombosis with mild symptoms. There was evidence of direct infiltration of anaplastic thyroid carcinoma into the left internal jugular vein. Sonographic and CT examinations also demonstrated multiple dilated collateral veins. © 2003 Wiley Periodicals, Inc. J Clin Ultrasound 31:111–115, 2003
Imaging findings in Mondor's disease
Authors: Yanik Bahar , Conkbayir Işik , Öner Özgür , Hekimoğlu Baki 
Published: January 2003

AbstractMondor's disease, or acute thrombophlebitis of superficial veins of the breast, occurs rarely, and little information is available in the medical literature on imaging findings in this disease. We present the case of a 59‐year‐old woman who underwent evaluation of a palpable, painful cord in her left breast associated with discoloration of the overlying skin. Mammography revealed a 10‐cm‐long linear density in her left breast. Gray‐scale sonography showed a noncompressible, hypoechoic, undulating tubular structure in the subcutaneous fat. Color Doppler imaging revealed no flow signal in this structure, although we observed arterial flow signals adjacent to it. We diagnosed Mondor's disease and treated the patient symptomatically; 6‐week follow‐up examinations demonstrated resolution of the venous thrombosis. The use of sonography, particularly color Doppler imaging, can aid in diagnosing Mondor's disease and in monitoring its resolution. © 2003 Wiley Periodicals, Inc. J Clin Ultrasound 31:103–107, 2003
Infantile scrotal pyocele simulating missed testicular torsion on sonography
Authors: Lim Gye‐Yeon , Lim Soo‐Ah , Jeong Yeon‐Joo , Hahn Seong‐Tae , Lee Jae‐Mun 
Published: January 2003

AbstractWe present the case of a neonate with idiopathic infantile pyocele. Scrotal sonography revealed a complex fluid collection within the left scrotal sac containing septations and a fluid‐fluid level. The dependent region of the collection had moderate echogenicity, the slightly hypoechoic testis was not well defined, and the scrotal wall was thickened. Color Doppler sonography revealed mild hypervascularity in the thickened scrotal wall but no vascularity inside the testis. The sonographic findings suggested missed testicular torsion, but surgery revealed a pyocele, for which no source was identified. Radiologists should be aware that idiopathic infantile pyocele can mimic the Doppler sonographic findings in missed testicular torsion. © 2003 Wiley Periodicals, Inc. J Clin Ultrasound 31:116–118, 2003
Caput succedaneum mimicking a cephalocele
Authors: Gerscovich Eugenio O. , McGahan John P. , Jain Kiran A. , Gillen Marijo A. 
Published: January 2003

AbstractCaput succedaneum is relatively common at birth but infrequently diagnosed in utero. It has a benign prognosis, but it is very important not to misdiagnose it as a cephalocele, which carries a guarded prognosis. We present the case of a patient who experienced preterm labor and premature rupture of the membranes at 28 weeks' menstrual age. Our initial diagnosis was cephalocele, but after the male infant was delivered by cesarean section, examination revealed no bone defect, and our final diagnosis was caput succedaneum. We also discuss the sonographic findings and diagnostic differences between caput succedaneum, cephalocele, and other fetal head masses. © 2003 Wiley Periodicals, Inc. J Clin Ultrasound 31:98–102, 2003
Correlation between prostate cancer grade and vascularity on color doppler imaging: Preliminary findings
Authors: Tang Jie , Li Song , Li Junlai , Luo Yukun , Xu Jianhong , Zhang Yan , Li Xin , Shi Huaiyin , Zhang Gaokui 
Published: January 2003

AbstractPurposeWe examined the relationship between the amount of prostate cancer–associated vascularity as seen on color Doppler imaging and the tumor grade.MethodsTransrectal color Doppler imaging of the prostate was performed in 54 patients with prostate cancer. Color flow signal/total pixel ratios (SPRs) of selected images were calculated using the ratio of the number of pixels showing color Doppler signals to the total number of pixels within the lesion. All the patients underwent prostate biopsy guided by transrectal sonography. Gleason scores were determined from the biopsy specimens.ResultsColor Doppler signals were demonstrated in the lesions of 91% (49/54) of the patients. The mean SPRs of prostate cancers 3 cm or smaller and larger than 3 cm were 0.15 ± 0.07 and 0.11 ± 0.04 (± standard deviation), respectively (p < 0.05). The mean SPRs of well‐ (Gleason score of 2–4), moderately (Gleason 5–7), and poorly (Gleason 8–10) differentiated prostate cancers were 0.08 ± 0.03, 0.12 ± 0.06, and 0.17 ± 0.11, respectively (r = 0.45; p < 0.01).ConclusionsThe refinement of color Doppler equipment has improved the detection of color Doppler signals associated with prostate cancer. Our study shows a correlation between prostate cancer–associated vascularity as shown on color Doppler imaging and the tumor grade. © 2003 Wiley Periodicals, Inc. J Clin Ultrasound 31:61–68, 2003
Chest sonography versus lateral decubitus radiography in the diagnosis of small pleural effusions
Authors: Kocijančič Igor , Vidmar Ksenija , Ivanovi‐Herceg Zlata 
Published: January 2003

AbstractPurposeThe aim of this prospective study was to assess the value of chest sonography in the radiologic diagnosis of small pleural effusions (relative to expiratory lateral decubitus radiography) and to suggest gray‐scale sonographic criteria for detecting the presence of small pleural effusions.MethodsPatients referred for abdominal or chest sonographic evaluation for various reasons were also examined for sonographic features of pleural effusion from May 1, 1997, until January 31, 2000. Patients who had evidence of small pleural effusions were included. Patients with no such evidence served as a control group. Subsequently, all patients underwent erect posteroanterior and expiratory lateral decubitus chest radiography.ResultsOn chest sonography, 52 patients were found to have small pleural effusions. The control group consisted of 17 patients. The mean thickness of the pleural effusion was 9.2 mm on sonography and 7.6 mm on expiratory lateral decubitus radiography (p < 0.01). Compared with radiologic examination, chest sonography had a positive predictive value of 92% in the diagnosis of small pleural effusions in our study population.ConclusionsChest sonography showed a high degree of accuracy relative to that of lateral decubitus chest radiography in the diagnosis of small pleural effusions, which appeared as thin (usually 15 mm thick or less) anechoic areas that changed shape with the phases of respiration. © 2003 Wiley Periodicals, Inc. J Clin Ultrasound 31:69–74, 2003
Angiogenesis of the heart
Authors: Kutryk Michael J.B. , Stewart Duncan J. 
Published: January 2003

AbstractDespite continued advances in the prevention and treatment of coronary artery disease, there are still a large number of patients who are not candidates for the conventional revascularization techniques of balloon angioplasty and stenting, or coronary artery bypass grafting (CABG). Therapeutic angiogenesis, in the form of the administration of growth factor protein or gene therapy, has emerged as a promising new method of treatment for patients with coronary artery disease. The goal of this strategy is to promote the development of supplemental blood conduits that will act as endogenous bypass vessels. New vessel formation occurs through the processes of angiogenesis, vasculogenesis, and arteriogenesis, under the control of growth factors such as those that belong to the vascular endothelial growth factor (VEGF), fibroblast growth factor (FGF) and angiopoeitin (Ang) families of molecules. Preclinical studies have suggested that such an approach is both feasible and effective; however many questions remain to be answered. This review will address the elements of pharmacologic revascularization, focusing on gene and protein‐based therapy. The important growth factors, the vector (for gene therapy), routes of delivery, the desired therapeutic effect, and quantifiable clinical end points for trials of angiogenesis will all be addressed. Microsc. Res. Tech. 60:138–158, 2003. © 2003 Wiley‐Liss, Inc.
Endothelial cell tumors
Authors: Bell Cecil David 
Published: January 2003

AbstractHistorically, there has been much debate on the nature of infantile hemangiomas as either congenital malformations or benign neoplasms. Some vascular lesions that are present at birth and evidence no proliferative growth are considered to be congenital malformations; other post‐natal vascular tumors pursue aggressive and possibly lethal clinical courses. The literature of the last two decades has been reviewed with a hope of clarifying the pathogenesis and underlying molecular lesions of this diverse set of lesions. Genetic investigations of two diseases associated with vascular tumors and abnormalities, von Hippel‐Lindau disease, and Hereditary Hemorrhagic Telangiectasia have greatly added to our knowledge of vascular proliferation and provided a tantalizing clue to the pathogenesis of hemangioblastomas. Mutations have also been described in infantile hemangiomas. All of the entities considered, vascular neoplasms as well as malformations, have been examined for the expression of vascular growth factors, their receptors, and factors that appear to promote cell proliferation. Similarly, factors that either block or promote apoptosis have also been examined in various vascular lesions. These studies have in large confirmed our expectations about proliferating tumors that show upregulation of growth promoting factors and inhibition of those that promote apoptosis. In conclusion, although much has been learned about vascular physiology and the control of endothelial proliferation, and while understanding about the molecular pathogenesis of the two inherited diseases mentioned above is detailed but not yet complete, understanding of the pathogenesis of benign and malignant endothelial tumors remains vague. Microsc. Res. Tech. 60:165–170, 2003. © 2003 Wiley‐Liss, Inc.
Tumor angiogenesis of non–small cell lung cancer
Authors: Shijubo Noriharu , Kojima Hiroshi , Nagata Manabu , Ohchi Takashi , Suzuki Akihiro , Abe Shosaku , Sato Noriyuki 
Published: January 2003

AbstractLung cancer is one of the commonest causes of cancer death in developed countries. Recent evidence suggests that angoigenesis is related to poor prognosis in many solid tumors including non–small cell lung cancer (NSCLC). Angiogenesis is regulated by a complex interaction among growth factors and cytokines and influenced by proteolytic enzymes such as plasminogen activators and matrix metalloproteases, expression of adhesion molecules, and distribution of extracellular matrices. Fibroblasts, macrophages, mast cells, and endothelial cells themselves also affect angiogenesis. This review concentrates on angiogenic growth factors including vascular endothelial growth factor, angiopoietins, platelet derived endothelial growth factor, and basic fibroblast growth factor, proteases, adhesion molecules including vascular endothelial cadherin and integrins, osteopontin, and mast cell products in tumor angiogenesis of NSCLC. Microsc. Res. Tech. 60:186–198, 2003. © 2003 Wiley‐Liss, Inc.
Biology of angiogenesis in tumors of the gastrointestinal tract
Authors: Reinmuth Niels , Parikh Alexander A. , Ahmad Syed A. , Liu Wenbiao , Stoeltzing Oliver , Fan Fan , Takeda Akihiko , Akagi Morihisa , Ellis Lee M. 
Published: January 2003

AbstractThe realization that the growth and spread of tumors are dependent on angiogenesis has created new avenues of research designed to help us to better understand cancer biology and to facilitate the development of new therapeutic strategies. However, the process of angiogenesis consists of multiple, sequential, and interdependent steps with a myriad of positive and negative regulators of angiogenesis being involved. The survival of tumors and thus their metastases are dependent upon the balance of endogenous angiogenic and anti‐angiogenic factors such that the outcome favors increased angiogenesis. Several growth factors have been identified that regulate angiogenesis in cancers of the gastrointestinal tract. These include pro‐angiogenic factors like vascular endothelial growth factor (VEGF) and anti‐angiogenic factors, i.e., thrombospondin. The following review provides a brief overview about the most important factors that are involved in the angiogenic process in tumors derived from colon, stomach, and pancreas. A thorough understanding of the role these factors play in the angiogenic process may lead to the development of novel therapeutic antineoplastic strategies. Microsc. Res. Tech. 60:199–207, 2003. © 2003 Wiley‐Liss, Inc.
Angiogenesis in brain tumors
Authors: Lopes M. Beatriz S. 
Published: January 2003

AbstractAngiogenesis is a complex process regulated by multiple stimulatory and inhibitory factors that are able to modulate the migration and/or proliferation of microvascular cells with the objective of formation of neovasculature from preexisting vessels. It involves well‐coordinated steps including production and release of angiogenic factors, proteolytic degradation of extracellular matrix components to allow formation of capillary sprout, proliferation and directional migration of microvascular cells, and the final composition of new vessels [Senger (1996) Am. J. Pathol. 149:1–7]. Angiogenesis is present in a number of hypoxic and/or ischemic conditions in the central nervous system, in particular in infarctions and infectious processes. Angiogenesis also plays an important role in malignant primary tumors. Glioblastomas, the most malignant gliomas in adults, are among the most angiogenic of all human tumors. This review will examine recent data of the role of angiogenic growth factors in the neoplastic and reactive conditions in the brain. Microsc. Res. Tech. 60:225–230, 2003. © 2003 Wiley‐Liss, Inc.
Architectonics of crayfish ganglia
Authors: Mulloney Brian , Tschuluun Naranzogt , Hall Wendy M. 
Published: January 2003

AbstractThe central nervous system of crayfish consists of a chain of segmental ganglia that are linked by cables of intersegmental axons. Each ganglion contains a highly‐ordered core of longitudinal tracts, vertical tracts, commissures, and synaptic neuropils. We review from a technical perspective the history of the description of these ganglia, and recognize four episodes of progress. Each major innovation in anatomical methods has led to new insight into the structure and function of this nervous system, and new awareness of the structural patterns that are common to the CNS of all arthropods. Ganglia in different segments of the body differ in size, and appear to differ in anatomy. From a comparison of the structures of the cores of abdominal, thoracic, and subesophageal ganglia, we argue that this apparent difference is illusory. Rather, each of these ganglia is organized on the same plan, a plan also found in insect segmental ganglia. The apparent differences follow from longitudinal compression during development and from allometric growth of particular neuropils associated with innervation of the walking legs. Different authors have described the internal organization of ganglia in different segments, so we provide a cross‐reference to the nomenclatures they have introduced. We compare the locations of cell bodies of motor neurons and accessory neurons that innervate different peripheral structures, and demonstrate double‐labeling of certain GABAergic peripheral inhibitory neurons. Finally, we describe the construction of digital movies of serial sections of these ganglia, and discuss their utility. Microsc. Res. Tech. 60:253–265, 2003. © 2003 Wiley‐Liss, Inc.
The effects of serotonin and ecdysone on primary sensory neurons in crayfish
Authors: Cooper Robin L. , Ward Elizabeth , Braxton Recennah , Li Hao , Warren Wendy M. 
Published: January 2003

AbstractThe overall behaviors and motivational states observed during social interactions and throughout the molting cycle of crayfish have been linked to the effects of humoral neuromodulators. Both serotonin (5‐HT) and a molt‐related hormone, 20‐hydroxyecdysone (20‐HE), are known to be present in the hemolymph of crustaceans. To determine if they alter the activity of a primary sensory neuron that monitors proprioceptive information, we examined their effects on the activity of the slow‐adapting muscle receptor organ (MRO) of the crayfish abdomen, a model sensory system that has been extensively studied. 5‐HT within the range of 100 nM to 1 μM, increases the firing frequency of the neuron during sustained stimulation. In experiments in which 20‐HE was added alone, an increase in the firing frequency also occurred, although to a lesser degree than that for 5‐HT at the same concentrations. When the MRO is first exposed to 20‐HE, followed sequentially by 5‐HT, the activity increases to about the same degree as in the reverse order of exposure. This outcome indicates that mixtures of these endogenous neuromodulators, at various levels, are more important in alternating behavior than the absolute level of any one of them introduced alone. Microsc. Res. Tech. 60:336–345, 2003. © 2003 Wiley‐Liss, Inc.
Amine neurochemistry and aggression in crayfish
Authors: Panksepp Jules B. , Yue Zhaoxia , Drerup Catherine , Huber Robert 
Published: January 2003

AbstractA primary goal of our research is to explore proximate mechanisms important in recruiting adaptive social behaviors. For instance, if one of three different behaviors may be expressed in a particular set of circumstances, how do neurochemical mechanisms bias behavior towards the expression of one act in lieu of the other possibilities? In this article, we review recent results suggesting that serotonin may play such a role in the control of aggression in crayfish. First, we summarize techniques that have been optimized for sensitive characterization of neurochemical profiles in crayfish. Then, borrowing concepts from behavioral ecology, we review a framework for quantitative investigation, which regards behavior as a set of individual decisions, each with a particular probability for occurrence, a motivational context, and controlled by its own distinct neurochemical mechanisms. Microsc. Res. Tech. 60:360–368, 2003. © 2003 Wiley‐Liss, Inc.
Uptake by mouse liver and intracellular fate of plasmid DNA after a rapid tail vein injection of a small or a large volume
Authors: Lecocq Michèle , Andrianaivo Fanjam , Warnier Marie‐Thérèse , Wattiaux‐De Coninck Simone , Wattiaux Robert , Jadot Michel 
Published: January 2003

AbstractBackgroundAn efficient gene transfer can be achieved in mouse liver by a rapid tail vein injection of a large volume of plasmid DNA solution (hydrodynamics‐based transfection). The mechanism of gene transfer by this procedure is not known. It must be related to the uptake and intracellular fate of DNA.MethodsWe have investigated the problem by following the uptake by mouse liver and the intracellular distribution of DNA after a rapid tail vein injection of a large (2.0 ml) or a small (0.2 ml) volume of 35S‐DNA solution. Total and acid‐soluble radioactivity were measured in liver homogenates at increasing times after injection, and their subcellular distributions were established by centrifugation methods and compared with the distributions of marker enzymes of the membrane compartments involved in endocytosis: alkaline phosphodiesterase (plasma membrane) and cathepsin C (lysosomes).Results35S‐DNA uptake by the liver is similar when a small or a large volume of injection is used but its degradation is markedly slower after a 2.0 ml injection. When a small volume of injection is given, distribution of radioactivity after differential centrifugation indicates that the plasmid DNA is endocytosed and reaches lysosomes where it is hydrolysed. After a large volume injection, part of 35S‐DNA has the same fate, another part remains acid‐precipitable for at least 1 h and is associated with structures sedimenting at low centrifugation speed in the nuclear fraction N. Analysis of that fraction by gradient centrifugation suggests that these structures are plasma membrane fragments that could originate from the apical domain of hepatocytes. The proportion of 35S‐DNA associated with hepatocytes is about doubled after a large volume injection. Fractionation of isolated hepatocytes by centrifugation confirms results obtained on the whole liver. Treatment of the N fraction or isolated hepatocytes with pancreatic DNAse illustrates that 35S‐DNA that remains bound to plasma membrane after a large volume injection is located on the outer face.ConclusionsThe fact that after an hydrodynamic injection 35S‐DNA remains bound to the outside face of the plasma membrane for at least 1 h indicates that it is not, or very slowly, internalised during that period. The relatively small difference in the amount of DNA picked up by hepatocytes depending on the type of injection could not explain the absence of expression after a conventional injection and the strong expression after a hydrodynamic injection. If DNA enters the cells by endocytosis, even after an hydrodynamic injection, its persistence at the outside face of the plasma membrane could favour transfection by allowing hepatocytes to dispose for a relatively long time of a reservoir of intact DNA. Copyright © 2002 John Wiley & Sons, Ltd.