1000 resultados para CAROTID-BODY


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Pyogenic liver abscess is a severe condition and a therapeutic challenge. Treatment failure may be due to an unrecognized ingested foreign body that migrated from the gastrointestinal tract. There has recently been a marked increase in the number of reported cases of this condition, but initial misdiagnosis as cryptogenic liver abscess still occurs in the majority of cases. We conducted the current study to characterize this entity and provide a diagnostic strategy applicable worldwide. To this end, data were collected from our case and from a systematic review that identified 59 well-described cases. Another systematic review identified series of cryptogenic-and Asian Klebsiella-liver abscess; these data were pooled and compared with the data from the cases of migrated foreign body liver abscess. The review points out the low diagnostic accuracy of history taking, modern imaging, and even surgical exploration. A fistula found through imaging procedures or endoscopy warrants surgical exploration. Findings suggestive of foreign body migration are symptoms of gastrointestinal perforation, computed tomography demonstration of a thickened gastrointestinal wall in continuity with the abscess, and adhesions seen during surgery. Treatment failure, left lobe location, unique location (that is, only 1 abscess location within the liver), and absence of underlying conditions also point to the diagnosis, as shown by comparison with the cryptogenic liver abscess series. This study demonstrates that migrated foreign body liver abscess is a specific entity, increasingly reported. It usually is not cured when unrecognized, and diagnosis is mainly delayed. This study provides what we consider the best available evidence for timely diagnosis with worldwide applicability. Increased awareness is required to treat this underestimated condition effectively, and further studies are needed.

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PURPOSE OF THE STUDY: This prospective study reports our preliminary results with local anaesthesia (LA) for carotid endarterectomy (CEA). MATERIAL AND METHODS: Twenty CEA in nineteen patients were performed using a three-stage local infiltration technique. CEA were performed through a short Duplex-assisted skin incision (median length: 55 mm) using a retro-jugular approach and polyurethane patch closure (median length: 35 mm). RESULTS: There were 13 men and 6 women with a mean age of 71.2 years. The indications of CEA were asymptomatic lesions in 11 cases, stroke in 7 cases and transient ischaemic attack in 2 cases. The median degree of internal carotid artery stenosis was 90%. One patient (5%) required an intraluminal shunt. There were no peri-operative deaths, stroke or conversion to general anaesthesia (GA). The median length of stay was 3 days. CONCLUSIONS: LA is a good alternative to GA. It can be used after a feasibility study and a short teaching procedure. In our centre, it is a safe and effective procedure associated with low morbidity, high acceptance by patients and a short hospital stay.

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BACKGROUND: Trichoplax adhaerens is the best-known member of the phylum Placozoa, one of the earliest-diverging metazoan phyla. It is a small disk-shaped animal that glides on surfaces in warm oceans to feed on algae. Prior anatomical studies of Trichoplax revealed that it has a simple three-layered organization with four somatic cell types. RESULTS: We reinvestigate the cellular organization of Trichoplax using advanced freezing and microscopy techniques to identify localize and count cells. Six somatic cell types are deployed in stereotyped positions. A thick ventral plate, comprising the majority of the cells, includes ciliated epithelial cells, newly identified lipophil cells packed with large lipid granules, and gland cells. Lipophils project deep into the interior, where they alternate with regularly spaced fiber cells whose branches contact all other cell types, including cells of the dorsal and ventral epithelium. Crystal cells, each containing a birefringent crystal, are arrayed around the rim. Gland cells express several proteins typical of neurosecretory cells, and a subset of them, around the rim, also expresses an FMRFamide-like neuropeptide. CONCLUSIONS: Structural analysis of Trichoplax with significantly improved techniques provides an advance in understanding its cell types and their distributions. We find two previously undetected cell types, lipohil and crystal cells, and an organized body plan in which different cell types are arranged in distinct patterns. The composition of gland cells suggests that they are neurosecretory cells and could control locomotor and feeding behavior.

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Body temperature of the European water-shrew Neomys fodiens was reinvestigated with intraperitoneally implanted radiotransmitters. Two animals, caged in outdoor conditions, were tested during February and March. Mean body temperature (Tb) during rest was 37.0°C, during activity 37.5°C. During stress of capture Tb increased to 38.4°C, and during a social confrontation mean Tb was 39.4°C. During forced swimming Tb decreased at a rate of 1.1°C per minute in an animal with wet fur. However, when kept in adequate conditions, animals could maintain their body temperature at a level of about 37°C in most of the tested situations. In water of 2.6°C, mean Tb after 6 min of forced swimming or diving was 37.4°C, comparable to Tb terrestrial activity. In these animals the fur remained dry even on its surface. The pelt of these shrews has a hydrophobic property which seems to be unique compared to other semiaquatic mammals.

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PURPOSE: To examine the reproducibility of carotid artery dimension measurements using 3T MRI. MATERIALS AND METHODS: Ten healthy volunteers underwent three scans on two occasions for assessment of total vessel wall area (TVWA), total luminal area (TLA), and minimum (MinT) and maximum (MaxT) vessel wall thickness. A double inversion-recovery (IR) fast gradient-echo (FGRE) sequence was used on a commercial 3T system. During the first visit the subjects were scanned twice. The third scan was performed at least four days later. One observer traced all scans, and a second observer retraced the first scan series. RESULTS: For TVWA an interclass correlation (ICC) of 0.994 was calculated with all three scans taken into account. The interobserver ICC was 0.984. The agreement between the scans for TLA showed an ICC of 0.982 with an interobserver ICC of 0.998. For MinT and MaxT an ICC of 0.843 and 0.935 were calculated, with interobserver ICCs of 0.860 and 0.726, respectively. CONCLUSION: With the use of a commercial 3T MR system, TVWA, TLA, and wall thickness measurements of the carotid artery can be assessed with good reproducibility.

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Purpose: Obesity is an established independent risk factor for chronic kidney disease. Thus, measurement of glomerular filtration rate (GFR) is important in this population. Traditionally, GFR has been indexed for body surface area (BSA), but this indexation may not be appropriate in obese individuals. Therefore, the objective of the study was to compare absolute GFR with GFR indexed for BSA and with GFR indexed for height. Methods and materials: The study was conducted in 66 families from the Seychelles islands that included several members with hypertension. GFR and effective renal plasma flow (ERPF) were measured using inulin and PAH clearances, respectively. Antihypertensive treatment, if used, was withheld 2 weeks before conducting the clearances. Participants with diabetes mellitus were excluded from the analysis. BSA was calculated using the Dubois formula. We assessed trend across BMI categories using a non parametric test. Results: Participants included 174 women and 127 men. The prevalence of hypertension was 61%, of which 68% were treated. The table shows that absolute GFR, GFR indexed for height, ERPF, filtration fraction were significantly higher across BMI categories. When GFR was indexed for BSA, the association between GFR and BMI categories was lost. Conclusion: Indexing GFR for BSA in overweight and obese individuals leads to a substantial underestimation of GFR. Filtration fraction, which does not depend on BSA, is higher in obese individuals, which suggests glomerular hyperfiltration. Indexing GFR for BSA therefore would mask the underlying glomerular hyperfiltration. As the number of nephrons does not increase with weight gain, absolute GFR represents a better marker of single nephron GFR and is more appropriate.

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In the n{body problem a central con guration is formed when the position vector of each particle with respect to the center of mass is a common scalar multiple of its acceleration vector. Lindstrom showed for n = 3 and for n > 4 that if n ? 1 masses are located at xed points in the plane, then there are only a nite number of ways to position the remaining nth mass in such a way that they de ne a central con guration. Lindstrom leaves open the case n = 4. In this paper we prove the case n = 4 using as variables the mutual distances between the particles.

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We study the families of periodic orbits of the spatial isosceles 3-body problem (for small enough values of the mass lying on the symmetry axis) coming via the analytic continuation method from periodic orbits of the circular Sitnikov problem. Using the first integral of the angular momentum, we reduce the dimension of the phase space of the problem by two units. Since periodic orbits of the reduced isosceles problem generate invariant two-dimensional tori of the nonreduced problem, the analytic continuation of periodic orbits of the (reduced) circular Sitnikov problem at this level becomes the continuation of invariant two-dimensional tori from the circular Sitnikov problem to the nonreduced isosceles problem, each one filled with periodic or quasi-periodic orbits. These tori are not KAM tori but just isotropic, since we are dealing with a three-degrees-of-freedom system. The continuation of periodic orbits is done in two different ways, the first going directly from the reduced circular Sitnikov problem to the reduced isosceles problem, and the second one using two steps: first we continue the periodic orbits from the reduced circular Sitnikov problem to the reduced elliptic Sitnikov problem, and then we continue those periodic orbits of the reduced elliptic Sitnikov problem to the reduced isosceles problem. The continuation in one or two steps produces different results. This work is merely analytic and uses the variational equations in order to apply Poincar´e’s continuation method.

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We prove the existence of infinitely many symmetric periodic orbits for a regularized rhomboidal five-body problem with four small masses placed at the vertices of a rhombus centered in the fifth mass. The main tool for proving the existence of such periodic orbits is the analytic continuation method of Poincaré together with the symmetries of the problem. © 2006 American Institute of Physics.

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Abstract In this paper we study numerically a new type of central configurations of the 3n-body problem with equal masses which consist of three n-gons contained in three planes z = 0 and z = ±β = 0. The n-gon on z = 0 is scaled by a factor α and it is rotated by an angle of π/n with respect to the ones on z = ±β. In this kind of configurations, the masses on the planes z = 0 and z = β are at the vertices of an antiprism with bases of different size. The same occurs with the masses on z = 0 and z = −β. We call this kind of central configurations double-antiprism central configurations. We will show the existence of central configurations of this type.

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Abstract. In this paper we prove the existence of central con gurations of the n + 2{body problem where n equal masses are located at the vertices of a regular n{gon and the remaining 2 masses, which are not necessarily equal, are located on the straight line orthogonal to the plane containing the n{gon passing through its center. Here this kind of central con gurations is called bi{pyramidal central con gurations. In particular, we prove that if the masses mn+1 and mn+2 and their positions satisfy convenient relations, then the con guration is central. We give explicitly those relations.

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Abstract. In this paper we study the relative equilibria and their stability for a system of three point particles moving under the action of a Lennard{Jones potential. A central con guration is a special position of the particles where the position and acceleration vectors of each particle are proportional, and the constant of proportionality is the same for all particles. Since the Lennard{Jones potential depends only on the mutual distances among the particles, it is invariant under rotations. In a rotating frame the orbits coming from central con gurations become equilibrium points, the relative equilibria. Due to the form of the potential, the relative equilibria depend on the size of the system, that is, depend strongly of the momentum of inertia I. In this work we characterize the relative equilibria, we nd the bifurcation values of I for which the number of relative equilibria is changing, we also analyze the stability of the relative equilibria.

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Le corps humain est l'objet privilégié d'action de la médecine, mais aussi réalité vécue, image, symbole, représentation et l'objet d'interprétation et de théorisation. Tous ces éléments constitutifs du corps influencent la façon dont la médecine le traite. Dans cette série de trois articles, nous abordons le corps sous différentes perspectives : médicale (1), phénoménologique (2), psychosomatique et socio-anthropologique (3). Nous proposons dans ce deuxième article de faire une différence entre le corps comme objet de connaissance ou de représentation et le corps tel qu'il est vécu (corps propre). Cette distinction, qui trouve son origine dans la psychiatrie phénoménologique, permet une approche du vécu des patients qui ne se limite pas aux catégories somatiques ou psychiques classiques en la matière. The human body is the object upon which medicine is acting, but also lived reality, image, symbol, representation and the object of elaboration and theory. All these elements which constitute the body influence the way medicine is treating it. In this series of three articles, we address the human body from various perspectives: medical (1), phenomenological (2), psychosomatic and socio-anthropological (3). This second article distinguishes between the body as an object of knowledge or representation and the way the body is lived. This distinction which originates in phenomenological psychiatry aims to understand how the patient experiences his body and to surpass the classical somatic and psychiatric classifications.