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21.
PURPOSE: Our goal was to report the CT manifestations of abdominal wall implantation metastases occurring after abdominal percutaneous procedure. METHOD: CT scans and clinical data of six patients with abdominal wall implantation metastases at the puncture site following abdominal percutaneous procedure were reviewed. The abdominal percutaneous procedures included drainage of intraperitoneal abscess in patients with colon or gastric cancer (n = 2), transhepatic biliary drainage in a patient with hilar cholangiocarcinoma (n = 1), biopsy of intrahepatic hepatocellular carcinoma (n = 1), biopsy of a metastatic left adrenal gland (n = 1), and laparoscopic cholecystectomy in a patient with unsuspected gallbladder cancer (n = 1). RESULTS: CT enabled the diagnosis of abdominal wall implantation metastasis in all six patients and showed coexisting intraabdominal tumor sites in five patients. All abdominal wall implantation metastases were homogeneous before intravenous administration of iodinated contrast material and became moderately heterogeneous on contrast-enhanced CT scan with marked enhancement relative to adjacent tissues. CONCLUSION: Abdominal wall implantation metastases are moderately heterogeneous on contrast-enhanced CT scan with marked enhancement relative to adjacent tissues. In most cases of abdominal wall implantation metastasis following abdominal percutaneous procedure, CT shows additional intraabdominal tumor sites. This complication may occur following a variety of abdominal percutaneous procedures (either radiological or surgical).  相似文献   
22.
Forest parameters, such as mean diameter at breast height (DBH), mean stand height (H) or volume per hectare (V), are imperative for forest resources assessment. Traditional forest inventory that is usually based on fieldwork is often difficult, time-consuming, and expensive to conduct over large areas. Therefore, estimating forest parameters in large areas using a traditional inventory approach combined with satellite data analysis can improve the spatial estimates of forest inventory data, and hence be useful for sustainable forest management and natural resources assessment. However, extracting practical information from satellite imagery for such purpose is a challenging task mainly because of insufficient knowledge linking forest inventory data to satellite spectral response. Here, we present the use of a cost-free Landsat-7 Enhanced Thematic Mapper Plus (ETM+) in order to explore whether it is possible to combine all available optical bands from a specific sensor for improving forest parameter spatial estimates, based on fieldwork at Lahav and Kramim Forests, in the Israeli Northern Negev. A generic strategy, based on morphological structuring element, convex hall and spectral band linear combination algorithms, was developed in order to extract the mathematical dependencies between the forest inventory measurements and linear combination sets of Landsat-7 ETM+ spectral bands, which yields the highest possible correlation with the forest inventory measured data. Using the mathematical dependency functions, we then convert the entire Landsat-7 ETM+ scenes into forest inventory parameter values with sufficient accuracy and tolerance errors needed for sustainable forest management. The root mean square error obtained between the measured and the estimated values for Lahav Forest are 0.70 cm, 0.29 m, and 1.48 m3 ha?1 for the mean DBH, H, and V, respectively, and for Kramim forest are 0.61 cm, 0.70 m, and 6.31 m3 ha?1, respectively. Furthermore, the suggested strategy could also be applied with other satellites data sources.  相似文献   
23.
We report a simple method using semiconductor quantum dots (QDs) to track the motion of intracellular proteins with a high sensitivity. We characterized the in vivo motion of individual QD-tagged kinesin motors in living HeLa cells. Single-molecule measurements provided important parameters of the motor, such as its velocity and processivity, as well as an estimate of the force necessary to carry a QD. Our measurements demonstrate the importance of single-molecule experiments in the investigation of intracellular transport as well as the potential of single quantum-dot imaging for the study of important processes such as cellular trafficking, cell polarization, and division.  相似文献   
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Nanoparticles are now utilized in many diverse biological and medical applications. Despite this, it remains challenging to tailor their surface for specific molecular targeting while maintaining high biocompatibility. To address this problem, we evaluate a phytochelatin-related peptide surface coating to produce functional and biocompatible nanoparticles (NPs) based on fluorescent InP/ZnS and CdSe/ZnS or superparamagnetic FePt and Fe(3)O(4). Using a combination of transmission electron microscopy, size-exclusion chromatography and gel electrophoresis (GE), we demonstrate the excellent colloidal properties of the peptide-coated NPs (pNPs) and the compact nature of the coating (~4?nm thickness). We develop a simple protocol for the monofunctionalization of the pNPs with targeting biomolecules, by combining covalent conjugation with GE purification. We then employ functionalized InP/ZnS pNPs in a live-cell, single-molecule imaging application to specifically target and detect individual proteins in the cell membrane. These findings showcase the versatility of the peptides for preparing compact NPs of various compositions and sizes, which are easily functionalized, and suitable for a broad range of biomedical applications.  相似文献   
27.
We report a case of wirsungorrhagia related to rupture of a pseudoaneurysm into the duct of Wirsung in a patient with chronic pancreatitis. Upper gastrointestinal endoscopy showed blood coming from the papilla of Vater suggesting wirsungorrhagia. Non-contrast computed tomography showed a spontaneous hyperdensity and arteriography showed an extravasation of contrast within a very large duct of Wirsung confirming wirsungorrhagia. Arteriography and dynamic computed tomography revealed a pseudoaneurysm from the left gastric artery. The pseudoaneurysm was successfully embolized with four steel microcoils, after super-selective catheterization of small branch of the left gastric artery, keeping gastric and liver vascularization.  相似文献   
28.
BACKGROUND: The ventilatory response to hypoxia is composed of the stimulatory activity from peripheral chemoreceptors and a depressant effect from within the central nervous system. Morphine induces respiratory depression by affecting the peripheral and central carbon dioxide chemoreflex loops. There are only few reports on its effect on the hypoxic response. Thus the authors assessed the effect of morphine on the isocapnic ventilatory response to hypoxia in eight cats anesthetized with alpha-chloralose-urethan and on the ventilatory carbon dioxide sensitivities of the central and peripheral chemoreflex loops. METHODS: The steady-state ventilatory responses to six levels of end-tidal oxygen tension (PO2) ranging from 375 to 45 mmHg were measured at constant end-tidal carbon dioxide tension (P[ET]CO2, 41 mmHg) before and after intravenous administration of morphine hydrochloride (0.15 mg/kg). Each oxygen response was fitted to an exponential function characterized by the hypoxic sensitivity and a shape parameter. The hypercapnic ventilatory responses, determined before and after administration of morphine hydrochloride, were separated into a slow central and a fast peripheral component characterized by a carbon dioxide sensitivity and a single offset B (apneic threshold). RESULTS: At constant P(ET)CO2, morphine decreased ventilation during hyperoxia from 1,260 +/- 140 ml/min to 530 +/- 110 ml/ min (P < 0.01). The hypoxic sensitivity and shape parameter did not differ from control. The ventilatory response to carbon dioxide was displaced to higher P(ET)CO2 levels, and the apneic threshold increased by 6 mmHg (P < 0.01). The central and peripheral carbon dioxide sensitivities decreased by about 30% (P < 0.01). Their ratio (peripheral carbon dioxide sensitivity:central carbon dioxide sensitivity) did not differ for the treatments (control = 0.165 +/- 0.105; morphine = 0.161 +/- 0.084). CONCLUSIONS: Morphine depresses ventilation at hyperoxia but does not depress the steady-state increase in ventilation due to hypoxia. The authors speculate that morphine reduces the central depressant effect of hypoxia and the peripheral carbon dioxide sensitivity at hyperoxia.  相似文献   
29.
Obtained final ratings on 25 assessment dimensions for 382 candidates for high-level management positions in an Israeli corporation. The ratings were determined by an assessment center process, 2 clinically derived assessment scores, and a mechanically derived assessment score. For 49 of the assessees, scores were also available on a battery of paper-and-pencil cognitive tests. For all Ss, data were obtained on 2 criterion measures over a period of 4 yrs. Both the general intelligence rating formulated in the assessment center and the scores on the cognitive tests were found to be predictively invalid, while the personality measure proved valid. Despite the modest coefficients of predictive validity found for the other assessment center predictors, the economic utility analysis performed with an amended formula demonstrated a cost-effectiveness for the assessment center program. (French abstract) (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
30.
1-IotroductionRecentnumerousstudies{1~8]ontheinhibition0fcorrosionofcarbonsteelinacidicsoluti0nsatdifferenttemperaturesindicatethegrowinginterestinthissubject.Fromthestandpointofindustrialappli-cationsthecorrosi0nproblemwhichpr0ducedfr0mtheaggressivefiuids(e.g.HCl)isaveryimp0rtantproblemsinceitisusedf0rmanyprocessesaspick-lingandacidcleaning.Theinhibitionofcorrosi0nofsteelinacidicmediabydifferenttypes0f0rganiccompoundshasbeenwidely,t.di.d[9~i4].Theexist-ingdatashowthatmostoforganicinhibit0rsa…  相似文献   
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