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801.
FP Cappuccio R Allan J Barron GA MacGregor VA Murday 《Canadian Metallurgical Quarterly》1999,13(1):79-80
A transjugular central venous catheter was inadvertently sutured to the wall of the right atrium in a 63-year-old female during coronary bypass surgery. Using two nitinol Goose Neck snares via a transfemoral and a transjugular approach the catheter was severed into two pieces and retrieved percutaneously. 相似文献
802.
Those who are physically attractive reap many benefits--from higher average wages to a wider variety of mate choices. Recent studies have investigated what constitutes beauty and how beauty affects explicit social judgments, but little is known about the perceptual or cognitive processing that is affected by aesthetic judgments of faces and why beauty affects our behavior. In this study, the authors show that beauty is perceived when information is minimized by masking or rapid presentation. Perceiving and processing beauty appear to require little attention and to bias subsequent cognitive processes. These facts may make beauty difficult to ignore, possibly leading to its importance in social evaluations. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
803.
S Singh PI Johnson A Javed TS Gray VA Lonchyna RD Wurster 《Canadian Metallurgical Quarterly》1999,99(3):411-419
BACKGROUND: Cardiac ganglia were originally thought to contain only cholinergic neurons relaying parasympathetic information from preganglionic brain stem neurons to the heart. Accumulating evidence, however, suggests that cardiac ganglia contain a heterogeneous population of neurons that synthesize or respond to several different neurotransmitters and neuropeptides. Reports regarding monoamine and histamine synthesis and neurotransmission within cardiac ganglia, however, present conflicting information or are limited in number. Furthermore, very few studies have examined the neurochemistry of adult human cardiac ganglia. The purpose of this study was, therefore, to determine whether monoamine- and histamine-synthesizing enzymes and neurotransmitters exist within neurons of adult human cardiac ganglia. METHODS AND RESULTS: Human heart tissue containing cardiac ganglia was obtained during autopsies of patients without cardiovascular pathology. Avidin-biotin complex immunohistochemistry was used to demonstrate tyrosine hydroxylase, L-dopa decarboxylase, dopamine beta-hydroxylase, phenylethanolamine-N-methyltransferase, tryptophan hydroxylase, and histidine decarboxylase immunoreactivity within neurons of cardiac ganglia. Dopamine, norepinephrine, serotonin, and histamine immunoreactivity was also found in ganglionic neurons. Omission or preadsorption of primary antibodies from the antisera and subsequent incubation with cardiac ganglia abolished specific staining in all cases examined. CONCLUSIONS: Our results suggest that neurons within cardiac ganglia contain enzymes involved in the synthesis of monoamines and histamine and that they contain dopamine, norepinephrine, serotonin, and histamine immunoreactivity. Our findings suggest a putative role for monoamine and histamine neurotransmission within adult human cardiac ganglia. Additional, functional evidence will be necessary to evaluate what the physiological role of monoamines and histamine may be in neural control of the adult human heart. 相似文献
804.
To support quantitative design of ultra-high-strength (UHS) secondary-hardening steels, the precipitation of cementite prior to the precipitation of the M2C phase is investigated using a model alloy. The microstructure of cementite is investigated by transmission electron microscopy (TEM) techniques. Consistent with earlier studies on tempering of Fe-C martensite, lattice imaging of cementite suggests microsyntactic intergrowth of M5C2 (Hägg carbide). The concentration of substitutional alloying elements in cementite are quantified by high-resolution analytical electron microscopy (AEM) using extraction replica specimens. Quantification of the substitutional elements in cementite confirms its paraequilibrium (PE) state with ferrite at the very early stage of tempering. The implications of these results are discussed in terms of the thermodynamic driving force for nucleation of the primary-strengthening, coherent M2C carbide phase. The ferrite-cementite PE condition reduces the carbon concentration in the ferrite matrix with a significant reduction of M2C driving force. The kinetics of dissolution of PE cementite and its transition to other intermediate states will also influence the kinetics of secondary hardening behavior in UHS steels. 相似文献
805.
Dynamics of macrophage and T cell infection by HIV 总被引:1,自引:0,他引:1
In eukaryotes, mitogen-activated protein kinases (MAPKs) are part of signaling modules that transmit diverse stimuli, such as mitogens, developmental cues, or various stresses. Here, we report a novel alfalfa MAPK, Medicago MAP kinase 3 (MMK3). Using an MMK3-specific antibody, we detected the MMK3 protein and its associated activity only in dividing cells. The MMK3 protein could be found during all stages of the cell cycle, but its protein kinase activity was transient in mitosis and correlated with the timing of phragmoplast formation. Depolymerization of microtubules by short treatments with the drug amiprophosmethyl during anaphase and telophase abolished MMK3 activity, indicating that intact microtubules are required for MMK3 activation. During anaphase, MMK3 was found to be concentrated in between the segregating chromosomes; later, it localized at the midplane of cell division in the phragmoplast. As the phragmoplast microtubules were redistributed from the center to the periphery during telophase, MMK3 still localized to the whole plane of division; thus, phragmoplast microtubules are not required to keep MMK3 at this location. Together, these data strongly support a role for MMK3 in the regulation of plant cytokinesis. 相似文献
806.
Byrne Brian; Coventry William L.; Olson Richard K.; Wadsworth Sally J.; Samuelsson Stefan; Petrill Stephen A.; Willcutt Erik G.; Corley Robin 《Canadian Metallurgical Quarterly》2010,102(1):32
It is often assumed that differences in teacher characteristics are a major source of variability in children's educational achievements. We examine this assumption for early literacy achievement by calculating the correlations between pairs of twin children who either shared or did not share a teacher in kindergarten, Grade 1, and Grade 2. Teacher effects—or, more strictly, classroom effects—would show up as higher correlations for same-class than for different-class twin pairs. Same-class correlations were generally higher than different-class correlations, though not significantly so on most occasions. On the basis of the results, we estimate that the maximum variance accounted for by being assigned to the same or different classrooms is 8%. This is an upper-bound figure for a teacher effect because factors other than teachers may contribute to variation attributable to classroom assignment. We discuss the limitations of the study and draw out some of its educational implications. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
807.
A prospective randomized study of 106 patients with unilateral primary inguinal hernia who underwent "tension-free" mesh repair was carried out. Fifty-nine procedures (group A) were performed by a single experienced surgeon and 47 (group B) procedures were performed by a team of residents each with an experience level of less than ten cases. In group A the length of operation was statistically shorter; local anesthesia was more frequently used in group A, while intra-operative sedation and general anesthesia were more frequently used in group B. A subgroup of twenty patients (group C) operated on by residents with a personal experience of at least 5 tension free repairs was selected. No statistically significant difference in operation time and in anesthesia used were found between group A and group C. No significant difference was found between group A and group B in morbidity rate, mean postoperative stay, median time to return to work, and recurrence rate. Because easy, efficacy, and minimally invasive, the tension-free mesh repair remains the gold standard in the treatment of inguinal hernia. 相似文献
808.
809.
OBJECTIVES: Autologous fat has been used as a bulking implant material for stress urinary incontinence. There is considerable controversy as to the ultimate fate of the grafted fat. This study was conducted to determine the fate of autogenous fat implanted into the bladder of rats. METHODS: Two groups of adult female rats were studied. In the test animals (group 1, n = 20), mesenteric adipose tissue (1 mL) was harvested and homogenized with an equal weight of sterile saline. Using a 25-gauge needle, 0.5 g of saline-fat mixture was injected into the dorsal bladder neck submucosa. Control animals (group 2, n = 12) were injected with sterile saline only. A subset of animals from each group were killed after 7, 35, 105, and 1 50 days, and the bladder and urethra were fixed. The fixed tissue was examined microscopically and photographed at each follow-up period. RESULTS: Seven days after injection of fat, there was a pronounced acute inflammatory reaction with numerous polymorphonuclear leukocytes and macrophages at the site of fat injection. There was minimal inflammatory reaction at the site of saline injection. By day 35, most of the fat had been eliminated by these phagocytes because of severe acute and chronic inflammation. By day 105, the submucosa tissue of the experimental rats had returned to normal visually and to a flat surface, lacking the appearance of a sizable "bulge" as shown at days 0 and 7. Histopathologic findings were also similar to the control rats. Inflammatory cells were no longer present by day 105. CONCLUSIONS: The implantation of homogenized, autologous fat in the rat urinary bladder submucosa causes acute and chronic inflammation and fat necrosis. The severe phagocytosis at the implant sites eliminates the vast majority of the devitalized implanted fat during the first month. 相似文献
810.
We consider a tangent-space representation of surfaces that maps each point on a surface to the tangent plane of the surface at that point. Such representations are known to facilitate the solution of several visibility problems, in particular, those involving silhouette analysis. In this paper, we introduce a novel class of distance fields for a given surface defined by its tangent planes. At each point in space, we assign a scalar value which is a weighted sum of distances to these tangent planes. We call the resulting scalar field a 'tangential distance field' (TDF). When applied to triangle mesh models, the tangent planes become supporting planes of the mesh triangles. The weighting scheme used to construct a TDF for a given mesh and the way the TDF is utilized can be closely tailored to a specific application. At the same time, the TDFs are continuous, lending themselves to standard optimization techniques such as greedy local search, thus leading to efficient algorithms. In this paper, we use four applications to illustrate the benefit of using TDFs: multi-origin silhouette extraction in Hough space, silhouette-based view point selection, camera path planning and light source placement. 相似文献