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71.
MF Kudriashova 《Canadian Metallurgical Quarterly》1998,84(8):821-823
OBJECTIVE: Few cases of verrucous carcinoma of the penis with foci of invasive squamous cell carcinoma have been reported and denominated "hybrid tumors". The accuracy of this term is discussed in this paper. METHODS/RESULTS: A huge penile mass in a patient that had undergone three previous operations for lesions diagnosed as verrucous carcinoma is reported. Partial penectomy was performed. Histological examination showed a very well-differentiated squamous cell carcinoma. PCR (polymerase chain reaction) did not detect any type of human papillomavirus (HPV) in the tumor. CONCLUSIONS: Verrucous carcinoma is a strictly-defined lesion with a different biological behaviour from that of squamous carcinoma. Preoperative deep biopsy may miss the squamous cell carcinoma. Definitive diagnosis can only be achieved by histological examination of the surgical specimen. In future, DNA studies could possibly support preoperative diagnosis of this lesion. 相似文献
72.
D Slobodkin PG Zielske JL Kitlas MF McDermott S Miller R Rydman 《Canadian Metallurgical Quarterly》1998,32(5):537-543
STUDY OBJECTIVE: To demonstrate the feasibility of systematic immunization against influenza and pneumococcus in a public emergency department. METHODS: This was a demonstration project conducted from October 21, 1996, through December 2, 1996, at Cook County Hospital, an inner-city hospital with a 1996 adult ED census of 120,449. Seventy-eight percent of patients are uninsured; 92% are people of color; 73% deny having a primary physician. Only 15% have emergency complaints. Nurses received standing orders that all nonemergency adult patients meeting Centers for Disease Control and Prevention criteria for high risk should be offered immunization against influenza and pneumococcus at triage. Cash prizes were offered to nurses appropriately immunizing the most patients. The date of immunization was entered into the computerized patient registration system, available to all providers within the county system. From November 4 through November 18, an extra nurse was assigned to triage to test for improvement in immunization rates. A time-motion study determined the time required per immunization on the basis of a convenience sample of 8 nurses drawn from all 3 shifts. RESULTS: Only 3% of identified high-risk patients reported previous pneumococcal immunization. Despite extreme variation in nurse performance, 2,631 patients (24% of patients triaged) were screened, and 716 high-risk patients were identified (27% of patients screened). A total of 1234 patients were immunized against influenza, and 241 patients were appropriately immunized against pneumococcus. Sixty-one percent of high-risk patients with no contraindication to influenza immunization were immunized against influenza. Thirty-five percent of high-risk patients not previously immunized against pneumococcus were immunized against pneumococcus. Immunizations per shift per triage nurse varied from 0 to 24. Median time for all activities related to immunization was 4 minutes (range, 2 to 10 minutes). There was no increase in immunization rates with the addition of an extra nurse at triage (95% confidence interval for odds ratio, .929 to 1.153). CONCLUSION: Systematic immunization against influenza and pneumococcus is both needed and feasible in a public ED. "Buy-in" by nurses is variable. Increased staffing alone does not improve immunization rates. 相似文献
73.
74.
This paper presents two examples of how impedance cardiography may be used to interpret the hemodynamic influences on blood pressures measured during behavioral stress. In Study 1, blood pressure changes which were similar during two tasks were shown to have important differences in their cardiac output and vascular resistance components. During work on a reaction time task having aversive incentives compared with a neutral task, the blood pressure changes were seen to be associated with lowered vascular resistance and raised cardiac activity, a "fight-flight" pattern. In Study 2, blood pressure response differences between two subject groups working on an identical task were found to have blood pressure changes differing in their underlying cardiac and vascular components as measured by impedance. Such uses impedance cardiography have widespread potential application in psychophysiological research with humans. 相似文献
75.
A. Manera U. Rohde H.-M. Prasser T.H.J.J. van der Hagen 《Nuclear Engineering and Design》2005,235(14):1517-1535
This paper reports on the modeling and simulation of flashing-induced instabilities in natural-circulation systems, with special emphasis on natural-circulation boiling water reactors (BWRs). For the modeling the 4-equation two-phase model FLOCAL [Rohde, U., 1986. Ein teoretisches Modell fur Zweiphasen-stromungen in wassergekulthen Kernreaktoren und seine Anwendung zur Analyse des Naturumlaufs im Heizreaktor AST-500. Ph.D. dissertation, Akademie der Wissenschaften der DDR, Dresden], developed at the Forschungszentrum Rossendorf (FZR, Germany), has been used. The model allows for the liquid and vapor to be in thermal non-equilibrium and, via drift-flux models, to have different velocities.The phenomenology of the instability has been studied and the dominating physical effects have been determined. The results of the simulations have been compared qualitatively and quantitatively with experiments [Manera, A., van der Hagen, T.H.J.J., 2003. Stability of natural-circulation-cooled boiling water reactor during start up: experimental results. Nuc. Technol., 143] that have been carried out within the framework of a European project (NACUSP) on the CIRCUS facility. The facility, built at the Delft University of Technology in The Netherlands, is a water/steam 1:1 height-scaled loop of a typical natural-circulation-cooled BWR. 相似文献
76.
Gadolinium-enhanced magnetic resonance angiography of the pelvis in patients with erectile impotence
Michael K. Stehling Libin Liu Gerhard Laub Kurt Fleischmann Ulrike Rohde 《Magma (New York, N.Y.)》1997,5(3):247-254
This study evaluted the potential of contrast-enhanced digital-subtraction magnetic resonance angiography (CE-DS-MRA) for
noninvasive angiographic delineation of the arterial supply of the penis in patients with erectile dysfunction. After induction
of an erection with prostaglandin E, a three-dimensional fast imaging with steady-state precision (FISP) sequence with TE
of 1.8–2 milliseconds, TR of 4.4–5 milliseconds, and flip angle of 40°–60° was used to obtain high-resolution angiograms of
the pelvis and penis during the injection of gadolinium diethylenetriaminepentaacetic acid (Gd-DTPA) 0.3 mmol/kg body weight,
within 30–50 seconds. DS maximum intensity projections (MIPs) and multiplanar reconstructions (MPRs) were compared with clinical
work-up and directional Doppler ultrasound in 11 patients. In all 11 patients (100%), the arterial supply of the penis could
be delineated from the aortic bifurcation via the iliac and internal pudendal arteries to the dorsal and deep penile arteries.
Of the 22 internal pudendal arteries, 6 (27%) were occluded on CE-DS-MRA and 5 (23%) had stenoses, of which 4 (18%) were greater
than 50%. In 7 patients (64%) good correlation between CE-DS-MRA and clinical findings and/or Doppler ultrasound was found;
in 2 patients (18%), the correlation was moderate, and in 2 patients (18%) results were discrepant. In 6 patients (55%), MRA
provided additional information to the clinical and Doppler ultrasound work-up. CE-DS-MRA can delineate small sessels such
as the internal pudendal and penile arteries and thus has the potential to become a noninvasive angiography method in the
work-up of erectile impotence.
Supported by Siemens Medical Systems, Erlangen; Schering AG, Berlin; and Agfa-Gevaert AG, Leverkusen. 相似文献
77.
Two exploratory data analysis techniques the comap and the quad plot are shown to have both strengths and shortcomings when analysing spatial multivariate datasets. A hybrid of these two techniques is proposed: the quad map which is shown to overcome the outlined shortcomings when applied to a dataset containing weather information for disaggregate incidents of urban fires. Common to the quad plot, the quad map uses Polya models in order to articulate the underlying assumptions behind histograms. The Polya model formalises the situation in which past fire incident counts are computed and displayed in (multidimensional) histograms as appropriate assessments of conditional probability providing valuable diagnostics such as posterior variance i.e. sensitivity to new information. Finally we discuss how new technology in particular Online Analytics Processing (OLAP) and Geographical Information Systems (GISs) offer potential in automating exploratory spatial data analyses techniques, such as the quad map. 相似文献
78.
Wei Wang Dejan Slepčev Saurav Basu John A. Ozolek Gustavo K. Rohde 《International Journal of Computer Vision》2013,101(2):254-269
Transportation-based metrics for comparing images have long been applied to analyze images, especially where one can interpret the pixel intensities (or derived quantities) as a distribution of ‘mass’ that can be transported without strict geometric constraints. Here we describe a new transportation-based framework for analyzing sets of images. More specifically, we describe a new transportation-related distance between pairs of images, which we denote as linear optimal transportation (LOT). The LOT can be used directly on pixel intensities, and is based on a linearized version of the Kantorovich-Wasserstein metric (an optimal transportation distance, as is the earth mover’s distance). The new framework is especially well suited for computing all pairwise distances for a large database of images efficiently, and thus it can be used for pattern recognition in sets of images. In addition, the new LOT framework also allows for an isometric linear embedding, greatly facilitating the ability to visualize discriminant information in different classes of images. We demonstrate the application of the framework to several tasks such as discriminating nuclear chromatin patterns in cancer cells, decoding differences in facial expressions, galaxy morphologies, as well as sub cellular protein distributions. 相似文献
79.
Aal Konstantin Boulus-Rdje Nina Rohde Markus 《Computer Supported Cooperative Work (CSCW)》2022,31(2):149-157
Computer Supported Cooperative Work (CSCW) - 相似文献
80.
Amanda J. Cox Hillary N. Bengtson Dr. Yulia V. Gerasimova Dr. Kyle H. Rohde Dr. Dmitry M. Kolpashchikov 《Chembiochem : a European journal of chemical biology》2016,17(21):2038-2041
Some natural enzymes increase the rate of diffusion‐limited reactions by facilitating substrate flow to their active sites. Inspired by this natural phenomenon, we developed a strategy for efficient substrate delivery to a deoxyribozyme (DZ) catalytic sensor. This resulted in a three‐ to fourfold increase in sensitivity and up to a ninefold improvement in the detection limit. The reported strategy can be used to enhance catalytic efficiency of diffusion‐limited enzymes and to improve sensitivity of enzyme‐based biosensors. 相似文献