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181.
The specificity of lymphocyte homing from the blood into a tissue is determined in part by complementary pairs of adhesion receptors on lymphocytes and endothelial cells termed homing receptors and vascular addressins, respectively. The mucosal vascular addressin involved in lymphocyte homing to Peyer's patches is a 66-kDa glycoprotein, MAdCAM-1. Investigation of the regulation and molecular genetics of MAdCAM-1 have been hampered by the lack of a murine cell line expressing this adhesion molecule. We show herein using indirect immunofluorescence studies that MAdCAM-1 can be induced on a murine endothelial cell line, bEnd.3, by cytokines and LPS. Western blot analysis of MAdCAM-1 purified by affinity column chromatography from TNF-alpha-treated bEnd.3 cells demonstrates a 66-kDa protein that comigrates in SDS-PAGE with the MAdCAM-1 constitutively found on high endothelial venules in murine mesenteric lymph nodes. Comparison of MAdCAM-1 expression on the bEnd.3 cells was made to the expression of adhesion molecules ICAM-1 and VCAM-1. MAdCAM-1 and VCAM-1 are not constitutively expressed on the bEND.3 surface but can be induced in a concentration-dependent manner by LPS, TNF-alpha, and IL-1. ICAM-1 is constitutively expressed on the endothelioma surface and expression is increased by TNF-alpha, IL-1, LPS, and IFN-gamma. Surface expression of MAdCAM-1 peaks 12 to 18 h after exposure to TNF-alpha and remains elevated at 48 h, whereas expression of VCAM-1 peaks at 4 h and inducible ICAM-1 peaks between 4 and 18 h. Interestingly, IFN-gamma has differential effects on expression of these three adhesion receptors. IFN-gamma alone induces VCAM-1 and enhances ICAM-1 expression, but does not induce MAdCAM-1. Furthermore, although, preincubation of bEND.3 cells with IFN-gamma modestly increases the induction of ICAM-1 and VCAM-1 in response to TNF-alpha and IL-1, it dramatically reduces the TNF-alpha, IL-1, and LPS-induced expression of MAdCAM-1. MAdCAM-1 on bEnd.3 cells is functional as the murine T lymphoma TK1, known to bind MAdCAM-1, also binds to TNF-alpha-stimulated endothelioma but not to unstimulated cells. This binding is blocked by the antibodies against MAdCAM-1 and against the alpha 4-chain of its integrin receptor, alpha 4 beta 7, on TK1 cells.(ABSTRACT TRUNCATED AT 400 WORDS)  相似文献   
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Tomographic registration, a method that makes possible accurate patient registration directly from projection data, consists of three processing steps: (i) manual coarse positioning, (ii) tomographic projection set acquisition, and (iii) computer mediated refined positioning. In the coarse positioning stage, the degree of patient alignment is comparable with that achieved with the standard radiotherapy set-up. However, the accuracy requirements are somewhat more relaxed in that meticulous alignment of the patient using external laser indicators is not necessary. Instead, tomographic projection sets are compared with planning CTs in order to achieve improved patient set-up. The projection sets are cross-correlated to obtain the best-fit translation and rotation offsets. The algorithm has been tested on synthetic data with the incorporation of varying amounts of Gaussian pseudo-random noise. These tests demonstrate the algorithm's stability and also confirm that alignment can be achieved with an accuracy of less than one projection pixel.  相似文献   
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OBJECTIVE: To describe some of the most severe features of eosinophilia-myalgia syndrome (EMS) and identify potential prognostic indicators. METHODS: Systematic review of data from initial case reports and from followup supplemental death report forms forwarded to the national surveillance system administered by the US Centers for Disease Control (CDC). RESULTS: As of August 10, 1991 36 deaths related to EMS had been reported to CDC. Among all patients fitting the surveillance case definition for EMS, we found that patients who died were older, had higher absolute leukocyte and eosinophil counts, and reported a greater frequency of cough or dyspnea, neuropathy, hepatomegaly, leukocytosis, and elevated erythrocyte sedimentation rate. All patients who died had illnesses affecting multiple organ systems. Of the 36 patients who died, 33 (92%) had neuromuscular sequelae, 29 (81%) had pulmonary complications, and 23 (64%) had cardiac manifestations. The most commonly observed disease process leading to death was progressive polyneuropathy and myopathy (24 of the 36 reported deaths) which produced complications of pneumonia and sepsis or respiratory failure due to weakness; cardiomyopathy was the underlying cause of death for 4 patients, primary pulmonary disease for 3, sudden death attributed to arrhythmia for 2, stroke for 2, and septic complications of therapy for one. CONCLUSION: Although neuromuscular complications were the most prominent sequelae among patients reported to have died, this is clearly a multisystemic disease. Older age and involvement of more than one organ system suggest a particularly poor prognosis, and the neuromuscular, pulmonary and cardiovascular sequelae appear to be the most worrisome.  相似文献   
185.
The author suggests a working classification of dermopertorators from analysis of his own designs and devices described in the literature for forming netlike skin grafts in the treatment of patients with large tissue defects. It is shown that the well-known dermoperforators require essential modernization. The most promising model is a device with plane knives whose simple technology allows their production to be organized in Soviet industry.  相似文献   
186.
In this work, we demonstrated a novel and effective approach on the use of low-cost electrodes, an eco-friendly substrate and zinc oxide (ZnO) micro or nanorods (MRs or NRs, respectively) for building triboelectric devices (TENGs). The reported strategy focuses on using low-cost materials and fabrication processes. For the first time and without any pre-treatment, an aluminum recyclable paper from the milk carton (named ARP) was used as a substrate and TENG bottom electrode. A systematic study on the growing of ZnO structures on ARP by chemical bath deposition has been carried out. We found that the ZnO rods size, and resistivity of the TENG upper electrode considerably influence the power density of the device. Such sustainable, low-priced ZnO-based TENGs can produce up to 1.6μW/cm2 output power density when operated at 50?Hz. The fabrication of an eco-friendly nanogenerator demonstrates the possibility of manufacturing low-cost, flexible, and large-area energy harvesting devices for future applications.  相似文献   
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The most reliable outcome variable for assessing periodontal regeneration is human histology; however, the morbidity associated with this technique makes it feasible only in isolated case studies designed to prove that a drug, device, or technique is capable of regenerating the lost periodontium including bone, cementum, and functionally oriented periodontal ligament. In the absence of this genuine variable, other "surrogate" variables must be used. Of these, measurement of new bone is the primary alternative. Direct bone measurements, including linear and volumetric assessment, are by far the best tools; however, the need for a second surgical procedure is a definite drawback of this technique. To overcome this problem, other outcomes have been employed: sounding bone measurements is a less invasive method, albeit it is also less accurate. Another tool that has been tested extensively is radiographic analysis. Conventional radiography is not useful in most regenerative trails where minimal or no crestal changes occur. The use of standardized radiographs and image processing techniques to measure alveolar bone changes has not significantly enhanced the applicability of this method. Digital subtraction radiography (DSR) offers some improvement over previous techniques; however, the correlation between the magnitude of clinical bone changes and changes in the digital image is yet to be substantiated. Other variables have been successfully used in regenerative studies. These include clinical attachment level changes, change in probing depth, and gingival recession. The information derived from these variables, especially attachment level changes, supplement and substantiate the direct bone measurements. Other variables that may be monitored are those associated with plaque formation, periodontal pathogens and gingival inflammation; while not direct measures of regeneration, these variables are likely to affect future prognosis and treatment stability. In summary, direct bone measurements are the most ideal surrogate outcome variable, although clinical attachment level measurements are commonly used in large-scale regenerative clinical trials. Clinical response may be assessed at different time intervals; however, the endpoint measurements for regenerative studies should be taken at least 12-months postoperatively.  相似文献   
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In eight cats the appetitive instrumental conditioned reflexes to light were elaborated by the method of "active choice" of reinforcement quality: the short-latency bar-pressing responses were reinforced with bread-meat mixture and the delayed responses were reinforced with meat. The animals differed in behavior strategy: six cats preferred the delayed pressings (the so-called "self-control" group), and two cats preferred the pressings with short delay (the so-called "impulsive" group). The multiunit activity in the basolateral amygdala and frontal cortex was recorded by chronically implanted nichrome semimicroelectrodes. The interactions of the neighboring neurons in the basolateral amygdala and the frontal cortex (within the local neuronal networks) and between the amygdalar and cortical neurons (distributed neuronal networks of amygdalar-frontal and fronto-amygdalar directions) were estimated by means of statistical crosscorrelation analysis of spike trains. The interneuronal cross-correlations were studied with delays in the range of 0-100 ms. The number of cross-correlations between the neuronal discharges both in the local and distributed networks was significantly higher in "impulsive" cats, mainly, with delays in the range of 0-30 ms. In both groups of animals the number of correlations was the highest during omissions of conditioned pressings, i.e., in cases of difficult choice of reinforcement. We suggest that the basolateral amygdala, frontal cortex, and amygdalar-frontal distributed neuronal networks are involved in the system of brain structures, which determine the individual features of animal behavior.  相似文献   
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