bluuebunny/crossref_metadata_2025_split huggingface dataset:
Experimental aspects of high‐intensity transient signals in the detection of emboli
Authors: Markus Hugh S. , Tegeler Charles H. 
Published: February 2007

AbstractExperimental studies in the 1960s and 1970s demonstrated the high sensitivity of Doppler ultrasound in detecting gaseous bubbles. More recent studies have shown that microscopic air bubbles, as well as glass microspheres as small as 5 μ to 20 μ, cause characteristic high‐intensity signals. Recently it has been demonstrated that less echogenic embolic materials such as thrombus, platelet aggregates, and atheroma can also be detected with a high sensitivity. Such “solid,” or formed‐element, emboli as small as 200 μ to 400 μ can be detected; the lower size limit of detection was due to an inability to make smaller embolic particles rather than to the sensitivity of the detection process itself. Analysis of the Doppler signals provides some information about embolus size and composition, but accurate characterization in clinical practice is not possible using current technology. Studies in experimental models have allowed the detailed description of embolic signals; they appear as a short‐duration, frequency‐focused increase in intensity, predominantly unidirectional in the direction of flow, and usually contained within the spectral envelope. In contrast, artifacts appear as a bidirectional, high‐intensity increase with maximum intensity at low frequencies. These differences have been exploited to develop automatic embolus detection programs, and an off‐line version has been successfully validated in an experimental model. © 1995 John Wiley & Sons, Inc.
Cerebrovascular regulation and vasoneuronal coupling
Authors: Daffertshofer M. , Hennerici M. 
Published: February 2007

AbstractMaintenance of cerebral perfusion pressure is a prerequisite for the prevention of cerebral ischemia. Physiological fluctuations in systemic perfusion pressure are compensated by cerebrovascular autoregulation. Cerebral hypoperfusion could result from (1) systemic hemodynamic failure (eg, distal to severe arterial stenosis), overcharging the vasoregulatory capacity; (2) dysfunction and exhaustion of cerebrovascular autoregulation; or (3) both.Ultrasound offers an excellent temporal resolution, is noninvasive, and is easily applicable for follow‐up investigations. Despite its poor spatial resolution, transcranial Doppler sonography has been used for determination of cerebral perfusion reserve studies measuring cerebral blood flow velocity (CBFV) during hypercapnia or application of vasoactive agents (eg, acetazolamide). This approach evaluates vasomotor regulation in patients with hemodynamic compromise distal to severe stenosis or occlusion of the brain supplying arteries.Monitoring CBFV during tilt table examinations directly measures cerebral autoregulation. In patients with systemic orthostatic hypotension, maintainance or failure of cerebrovascular compensation and, even more importantly, cerebrovascular dysautoregulation, despite normal systemic blood pressure regulation, may be demonstrated.Vasoneuronal coupling is reflected by CBFV variations during appropriate neuronal stimulation. Neuronal dysfunction is associated with CBFV abnormalities as exemplified by preconditions of focal cerebral dysfunction in the posterior cerebral artery (PCA) in migraineurs with aura, where massive alteration of vasoneuronal coupling and ischemia is threatening during spreading depression. A highly significant asymmetric gain of vasoneuronal coupling in the interictal state may act as a trigger mechanism in these patients.Testing for vasoneuronal coupling within the middle cerebral artery (MCA) territory is more difficult due to the poor spatial resolution with various neuronal stimuli (eg, motorsensory or cognitive paradigms), only eliciting local neuronal areas underrepresented in the MCA CBFV global changes. However, motor stimulation evoked CBFV may be used to indicate dysintegation of vasoneuronal coupling in the course of acute cerebral ischemia with sensorimotor hemiparesis and, moreover, seems to be of prognostic value regarding the motor deficit. © 1995 John Wiley & Sons, Inc.
New and future developments in cerebrovascular ultrasound, magnetic resonance angiography, and related techniques
Authors: Meairs Stephen , Röther Joachim , Neff Wolfgang , Hennerici Michael 
Published: February 2007

AbstractFour‐dimensional (4D) analysis of atherosclerotic plaque and wall motion, the application of 4D ultrasound to the study of atherogenesis, and the incorporation of ultrasound data into flow models for simulation of cerebrovascular hemodynamics are new frontiers in diagnostic ultrasound that use computer vision and optical flow techniques to exploit the full potential of real‐time imaging and Doppler studies. New approaches to improve blood vessel delineation with ultrasound include application of contrast agents, harmonic imaging, and red blood cell density imaging. An assessment of the potential clinical utility of these new developments in cerebrovascular ultrasound requires an analysis of comparable trends in magnetic resonance (MR) technology, eg, rapid advances in the fields of MR angiography, dynamic contrast‐enhanced MR, and MR diffusion imaging. Likewise, the value of ultrasound techniques for the measurement of blood flow to evaluate cerebrovascular hemodynamics must be compared to related methods in magnetic resonance, such as dynamic MR inflow tracking. This article addresses several new and future developments in cerebrovascular ultrasound and discusses their relative merits in terms of ongoing research in the field of magnetic resonance angiography, imaging, and related techniques. © 1995 John Wiley & Sons, Inc.
Gallbladder wall thickening in dengue hemorrhagic fever: An ultrasonographic study
Authors: Setiawan Melani W. , Samsi Tatang K. , Pool Thomas N. , Sugianto D. , Wulur H. 
Published: February 2007

AbstractThis study attempts to investigate whether gallbladder wall thickening (GBWT) measured by ultrasonography can be used in children as a reliable criterion to predict the onset of severe dengue hemorrhage fever (DHF). In this prospective study, we performed ultrasound examinations focusing on the gallbladder wall and the presence of intraperitoneal free fluid in 48 mild DHF cases (grades I–II) and 48 severe cases (grades III–IV). GBWT varied between 1 mm and 8 mm with a mean of 3.77 mm ± 2.04 mm. The mean value of DHF grades I and II (2.39 mm ± 1.48 mm) is significantly lower than that of grades III and IV (5.14 mm ± 1.54 mm), p < 0.001. GBWT exceeded 3 mm in only 16 of 48 (33.3%) grade I–II patients and in 45 of 48 (93.8%) grade III–IV patients. A significant positive correlation was apparent between GBWT and the severity of illness, p < 0.001. Patients with ascites have significantly thicker gallbladder walls than those without, p < 0.01. In clinically confirmed DHF cases, the sonographic finding of GBWT >3 mm to 5 mm, with 93.8% sensitivity, can be used as a criterion indicating the need for admission and monitoring. A GBWT of ⩾5 mm, with 91.7% specificity, is useful as a criterion for identifying DHF patients at high risk of developing hypovolemic shock. © 1995 John Wiley & Sons, Inc.
Pylorus subjacent to the gallbladder: An additional finding in hypertrophic pyloric stenosis
Authors: Levine Deborah , Wilkes David C. , Filly Roy A. 
Published: February 2007

AbstractWe have noted that sonographically positive cases of hypertrophic pyloric stenosis (HPS) demonstrate a distortion of normal anatomy in which the elongated pylorus displaces the duodenum and lies adjacent to and below the gallbladder. Ten consecutive cases of HPS diagnosed by ultrasound were reviewed. In each case the pylorus was imaged subjacent to the gallbladder. Sonograms from 100 infants from a different institution were then reviewed. There were 13 cases with the pylorus subjacent to the gallbladder, 12 of these met criteria for HPS. Recognition of this anatomic relationship may aid in the diagnosis of HPS. © 1995 John Wiley & Sons, Inc.
Flow reversal in the right anterior branch of the portal vein: “Bicolor portal vein” color Doppler analysis
Authors: Donoso Lluís , Parellada J. Antoni , Martínez‐Noguera Antonio , Sanchís Eduard , Sabaté Josep M. 
Published: February 2007

AbstractThe purpose of this study is to describe a phenomenon of bidirectional flow, “bicolor portal vein” (BPV), within the right anterior branch of the portal vein (RAPV), with color Doppler imaging (CDI). We prospectively studied with CDI the intrahepatic portal vein and its branches in 316 consecutive patients in search of areas of nonlaminar flow within the RAPV. Forty patients were excluded from the study due to varied conditions that precluded an accurate CDI study. A prospective design allowed us to record the frequency of appearance, systematically measure a set of parameters in each patient, and establish different groups for comparison.We found an area of BPV within the RAPV in six patients. Five of them had a history of liver disease (8.2% of the patients with known liver disease). The BPV was consistently portrayed as a well‐defined blue oval‐shaped area of flow reversal attached to the medial side of the RAPV immediately before its bifurcation, suggesting a rotary motion of blood. All six patients presented a transverse diameter of the RAPV significantly larger than the rest of the patients (p < 0.05). Furthermore, blood flow measurements within the RAPV of the six patients with BPV were found to be significantly higher when compared with the rest of the patients (<0.05).Knowledge of the possible presence of a BPV within the RAPV can prevent diagnostic confusion with reversal of flow, a truly pathologic condition related to liver disease. © 1995 John Wiley & Sons, Inc.
Degenerated uterine leiomyoma mimicking acute appendicitis: Sonographic diagnosis
Authors: Yacoe Marshall E. , Jeffrey R. Brooke 
Published: February 2007

AbstractThe present study reviews four cases in which degenerated uterine leiomyomas mimicked appendicitis clinically. The correct diagnosis was made prospectively by sonography in each case. Appendicitis was excluded by graded compression sonography and an exophytic uterine leiomyoma was identified at the point of maximal symptoms. The leiomyomas demonstrated central hypoechoic foci, but no detectable Doppler flow indicating necrosis. Although the phenomenon of a degenerated uterine leiomyoma mimicking appendicitis clinically is known, sonographic diagnosis has not been reported previously. The importance of making this diagnosis sonographically is that management of a degenerated leiomyoma is conservative and unnecessary surgery could be avoided. © 1995 John Wiley & Sons, Inc.
Ultrasound‐guided fine‐needle aspiration biopsy of solitary pulmonary nodules
Authors: Chen Chi‐Chiang , Hsu Wu‐Huei , Huang Chih‐Mei , Chen Chih‐Yi , Kwan Po‐Cheung , Chiang Chi‐Der 
Published: February 2007

AbstractUltrasound‐guided fine‐needle aspiration biopsy (US‐guided FNAB) was performed in 40 patients with solitary pulmonary nodules (SPNs) for evaluation of diagnostic results and complication rates. The final diagnoses of the 40 patients included 30 malignancies and 10 benign lesions. Using US‐guided FNAB, the diagnostic yields were 97% (29/30) in malignancies and 60% (6/10) in benign lesions. Of the 29 patients with cytologically proven malignancies, 12 underwent surgical resection. The correlation between cytological results and histologic diagnoses in these 12 was excellent (100%). The size of the nodule did not affect the diagnostic rate or complication rate. Only two patients (5%) developed minimal pneumothorax after US‐guided FNAB. We conclude that US‐guided FNAB is a useful, safe, and convenient diagnostic tool for SPN, and that malignant pulmonary nodules are more easily diagnosed than benign nodules. © 1995 John Wiley & Sons, Inc.
Cardiovascular effects of noradrenaline microinjection in the bed nucleus of the stria terminalis of the rat brain
Authors: Crestani C.C. , Alves F.H.F. , Resstel L.B.M. , Corrêa F.M.A. 
Published: February 2007

AbstractThe bed nucleus of the stria terminalis (BST) is a limbic structure involved in regulating the hypothalamic‐pituitary‐adrenal axis as well as in central cardiovascular control. We report here on cardiovascular effects caused by microinjection of noradrenaline (NA) in the BST of the rat brain and the peripheral mechanisms involved in their mediation. Injection of NA (3, 7, 10, 15, 30, or 45 nmol in 100 nl) in the BST of unanesthetized rats caused long‐lasting dose‐related pressor and bradycardiac responses. No responses were observed when the dose of 10 nmol NA was microinjected into surrounding structures, such as the anterior commissure, the stria terminalis, the fornix, and the internal capsule, indicating a predominant action at the BST. Additionally, microinjection of 50 nmol tyramine, an indirectly acting sympathomimetic amine, caused similar pressor response, indicating local NA release in the BST. Responses to NA microinjection in the BST were markedly reduced in urethane‐anesthetized rats, favoring the idea of a central action without significant leakage to the peripheral circulation. The pressor response was potentiated by i.v. pretreatment with the ganglion blocker pentolinium and blocked by i.v. pretreatment with the selective V1‐vasopressin antagonist dTyr(CH2)5(Me)AVP, suggesting its mediation by vasopressin release into circulation. The bradycardiac response to NA microinjected into the BST was also abolished by pretreatment with the vasopressin antagonist, indicating its reflex origin. In conclusion, results indicate that microinjection of NA into the BST evokes pressor responses, which are mediated by acute vasopressin release. © 2007 Wiley‐Liss, Inc.
Medicinal plant species with potential antidiabetic properties
Authors: Mentreddy Srinivasa Rao 
Published: February 2007

AbstractDiabetes mellitus is one of the world's major diseases. It currently affects an estimated 143 million people worldwide and the number is growing rapidly. In the USA alone, about 20.8 million or 7% of the population suffer from diabetes or related complications. The estimated direct and indirect costs of diabetes exceed US$ 132 billion annually. Plant‐based medicinal products have been known since ancient times, and several medicinal plants and their products (active natural principles and crude extracts) have been used to control diabetes in the traditional medicinal systems of many cultures worldwide, including those of the Asian Indians, Chinese and South Americans. A limited number of these plant species have been studied and validated for their hypoglycaemic properties using diabetic animal models and in clinical studies using human subjects. Several oral hypoglycaemic agents are the primary forms of treatment for diabetes. However, prominent side‐effects of such drugs are the main reason for an increasing number of people seeking alternative therapies that may have less severe or no side‐effects. Thus plant‐based herbal drugs or botanicals are emerging as the primary components of holistic approaches to diabetes management. In this review, selected species that have been validated for their hypoglycaemic or antihyperglycaemic properties using laboratory diabetic animal models and in clinical trials using human subjects, and reported in refereed journals are presented. Copyright © 2007 Society of Chemical Industry
Ring‐opening polymerization of epoxy end‐terminated poly(ethylene oxide) as a route to highly crosslinked materials with exceptional swelling behavior (II)
Authors: Laine Richard M , Kim Seung Gyoo , Rush Jason , Mollan Mathew , Sun Hei‐Jen , Lodaya Mayur 
Published: February 2007

AbstractHighly swellable poly(ethylene oxide) (PEO) gels were prepared by anionic ring‐opening polymerization of diepoxy end‐capped PEO (3400 g mol−1) and PEO (8000 g mol−1) using dianionic glycerol and glycolic acid initiators at scales of up to 50 g diepoxide. The glycerol‐derived materials swell to almost 20 times their mass in water. The driving force for rapid swelling appears to arise during ‘crystallization’, as segments between crosslinks are forced to pack under conditions that create high‐energy domains within the material. Solvation and therefore swelling are driven by the release of the resulting packing energy. These observations may offer insight into methods for designing other highly swellable materials. When the polyfunctional initiators have groups with different reactivities (e.g. alkoxide versus carboxylate), as might be expected, the more nucleophilic functional group appears to dominate the ring‐opening polymerization process. Copyright © 2007 Society of Chemical Industry
The polyoxaesters
Authors: Andjelić Saša , Jamiolkowski Dennis D , Bezwada Rao 
Published: February 2007

AbstractThis paper provides a review of a new class of synthetic absorbable polyesters, the ‘polyoxaesters’. We describe what they are and provide routes of preparation to the homopolymers, as well as their copolymers with lactones. Structure–property relationships are outlined and applications with commercial potential are discussed. Finally, two potential surgical applications, suture coatings and adhesion prevention barriers, are presented in more detail. Copyright © 2007 Society of Chemical Industry
Electrochemical polymerization of pyrrole in cholesteric liquid crystals: Morphology and optical properties
Authors: Goto Hiromasa 
Published: February 2007

AbstractElectrochemical polymerization in a cholesteric liquid‐crystal electrolyte was carried out. Polypyrrole thus synthesized in a cholesteric liquid‐crystal electrolyte could be clearly seen to form a specific morphology. The polypyrrole films exhibited chiroptical properties and formed various surface structures such as Schlieren, Nazca‐line, sea‐anemone, and wire‐loop structures. These structures that developed during polymerization were preserved even after washing. Moreover, no chiral molecule reacted chemically with the monomer during polymerization, and the electrolyte functioned only as a matrix chiral continuum. © 2006 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 45: 1377–1387, 2007.
Outcome of pulmonary function in Lemierre's disease‐associated acute respiratory distress syndrome
Authors: Cholette Jill M. , Caserta Mary , Hardy Dwight , Connolly Heidi V. 
Published: February 2007

AbstractPulmonary function in acute respiratory distress syndrome (ARDS) survivors typically returns to normal with the exception of a persistent reduction in carbon monoxide diffusion capacity (DLco). Septic thrombophlebitis of the internal jugular vein, (Lemierre's syndrome or postanginal sepsis) is a well‐described, albeit uncommon cause of ARDS in which metastatic pulmonary thromboemboli precipitate respiratory failure requiring ventilatory support. We describe convalescent pulmonary function in two survivors of Lemierre's disease‐associated ARDS, suggesting that the subset of Lemierre's syndrome induced ARDS survivors have an excellent long‐term pulmonary prognosis. Pediatr Pulmonol. 2007; 42:389–392. © 2007 Wiley‐Liss, Inc.
Use of a structural analogue versus a stable isotope labeled internal standard for the quantification of angiotensin IV in rat brain dialysates using nano‐liquid chromatography/tandem mass spectrometry
Authors: Lanckmans Katrien , Sarre Sophie , Smolders Ilse , Michotte Yvette 
Published: February 2007

AbstractQuantifying low concentrations of neuropeptides in microdialysates requires a selective and sensitive analysis technique, such as nano‐liquid chromatography/electrospray ionization tandem mass spectrometry (nanoLC/ESI‐MS/MS). However, we observed reduced accuracy of the method due to matrix effects. Indeed, ESI‐MS detection is known to be sensitive to matrix effects. Moreover, dialysates are complex mixtures of small molecules, peptides and other matrix compounds that can influence the ionization efficiency of the neuropeptide of interest and the stability of the peptide in the samples. In the study reported in this paper, we investigated whether the use of an internal standard (IS) can correct for these matrix effects. As a model compound for neuropeptides we used angiotensin IV (Ang IV). We compared the use of a structural analogue (norleucine1‐Ang IV) with a stable isotope labeled (SIL) analogue. Linearity of the method was improved when either of the proposed ISs were applied. Only when using the SIL‐IS could the repeatability of injection and the method's precision and accuracy be improved. Finally, the IS was able to correct for degradation of Ang IV in dialysates, prolonging the possible storage period of the samples. We conclude that the structural analogue is not suited as an IS and that the application of a SIL analogue is indispensable when quantifying Ang IV in dialysates using nanoLC/ESI‐MS/MS detection. Copyright © 2007 John Wiley & Sons, Ltd.
On the Production of X‐rays by Low Energy Ion Beams
Authors: Joy David C. , Meyer Harry M. , Bolorizadeh Mehdi , Lin Yinghong , Newbury Dale 
Published: February 2007

AbstractAlthough electron beams with energies of a few keV can excite fluorescent X‐ray production from solids, ion beams of comparable energy cannot do so. The reason for this situation is that it is the velocity of the incident particle, rather than its energy, which determines whether an ionization event can be generated. SCANNING 29: 1–4, 2007. Copyright © 2007 Wiley Periodicals, Inc.
Real Imaging and Size Values of Saccharomyces cerevisiae Cells with Comparable Contrast Tuning to Two Environmental Scanning Electron Microscopy Modes
Authors: Misirli Zulal , Öner Ebru Toksoy , Kirdar Betul 
Published: February 2007

AbstractThe combined application of electron microscopy (EM) is frequently used for the microstructural investigation of biological specimens and plays two important roles in the quantification and in gaining an improved understanding of biological phenomena by making use of the highest resolution capability provided by EM. The possibility of imaging wet specimens in their “native” states in the environmental scanning electron microscope (ESEM) at high resolution and large depth of focus in real time is discussed in this paper. It is demonstrated here that new features can be discovered by the elimination of even the least hazardous approaches in some preparation techniques, that destroy the samples. Since the analysis conditions may influence the morphology and the extreme surface sensitivity of living biological systems, the results obtained from the same cultured cell with two different ESEM modes (Lvac mode and wet mode) were compared. This offers new opportunities compared with ESEM‐wet/Lvac‐mode imaging, since wet‐mode imaging involves a real contrast and gives an indication of the changes in cell morphology and structure required for cell viability. In this study, wet‐mode imaging was optimized using the unique ability of cell quantities for microcharacterization in situ giving very fine features of topological effects. Accordingly, the progress is reported by comparing the results of these two modes, which demonstrate interesting application details. In general, the functional comparisons have revealed that the fresh unprocessed Saccharomyces cerevisiae cells (ESEM‐wet mode) were essentially unaltered with improved and minimal specimen preparation timescales, and the optimal cell viability degree was visualized and also measured quantitatively while the cell size remained unchanged with continuous images. SCANNING 29: 11–19, 2007. Copyright © 2007 Wiley Periodicals, Inc.