共查询到20条相似文献,搜索用时 15 毫秒
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Hummel P Yang GC Kumar A Cohen JM Winkler B Melamed J Scholes JV Jagirdar J 《Diagnostic cytopathology》2001,24(4):283-288
Fine-needle aspiration (FNA) cytology of soft-tissue tumors is evolving. As more experience is gained, we are becoming aware of potential pitfalls. We describe 2 cases of synovial sarcoma of the lung, primary and metastatic, in patients who had FNA biopsy performed on a lung mass. The cytologic smears showed extremely cellular groups of malignant small round cells, intersected by small blood vessels, with numerous loose single cells, in a background of macrophages and mature lymphocytes. The tumors displayed monomorphic cells forming rosettes and displaying occasional mitoses. A diagnosis of neuroendocrine tumor/primitive neuroepithelial tumor (PNET) was suspected. Furthermore, this suspicion was supported by immunohistochemical stains, which showed positivity for a neuroendocrine marker, Leu 7 (case 1), and for a neural marker, CD 99 (O 13 or HBA 71) (both cases); and negativity for cytokeratins (case 1). The resection specimen of case 1 had mostly tightly packed small round cells, with occasional rosettes, similar to the FNA biopsy, and focal areas composed of spindle cells, organized in a focal fibrosarcoma-like and hemangiopericytoma-like pattern. A balanced translocation between chromosomes X and 18, demonstrated by both karyotyping and fluorescent in situ hybridization (FISH), enabled us to make a diagnosis of synovial sarcoma, which was histologically classified as poorly differentiated. Case 2 was a metastatic biphasic synovial sarcoma of the arm, with a prominent epithelial component. Synovial sarcoma, when composed mainly of small round cells on cytologic smears, is a great mimicker of neuroendocrine/PNET tumors, with light microscopic and immunohistochemical overlap. Awareness of this potential pitfall may aid in preventing a misdiagnosis. Its recognition is of major concern, especially for the poorly differentiated variant, because it is associated with a worse prognosis. 相似文献
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Pronin I. N. Khokhlova E. V. Konakova T. A. Maryashev S. A. Pitskhelauri D. I. Batalov A. I. Postnov A. A. 《Neuroscience and behavioral physiology》2021,51(4):438-443
Neuroscience and Behavioral Physiology - Objective. To study the accumulation of 11C-methionine in primary brain tumors of different types and intact brain tissue. Materials and methods. A total of... 相似文献
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Lei Tang Xiao-Peng Zhang Ying-Shi Sun Yan-Ling Li Xiao-Ting Li Yong Cui Shun-Yu Gao 《Surgical and radiologic anatomy : SRA》2013,35(6):539-545
Purpose
To investigate the performance of spectral CT in the depiction of the gastrocolic ligament (GCL) compared to conventional polychromatic CT.Methods
Gemstone spectral CT and conventionally polychromatic CT examinations were randomly allocated to be performed on 62 consecutive patients. A total of 11 groups of monochromatic images were generated on energy levels ranging from 40 to 140 keV at an interval of 10 keV. A five-score classification system was used to evaluate the performances of CT images in the demonstration of GCL. The inter-observer agreement between two radiologists in their evaluation of the GCL by each method was evaluated using kappa statistics.Results
There were statistically significant differences between the spectral CT and polychromatic CT in their abilities to highlight the GCL (observer 1: χ2 = 18.310, P < 0.001; observer 2: χ2 = 19.780, P < 0.001). The distinct display (score ≥ 3) rates of the GCL by integrated monochromatic images were higher than that of polychromatic images (P < 0.001). The best energy level for displaying the GCL by spectral CT was 50–70 keV. The kappa value for the image scores on the integrated keV images between the two radiologists was higher than that for polychromatic CT images (P < 0.01).Conclusions
Spectral CT can improve the visualisation of the GCL compared to polychromatic CT. 相似文献6.
Kaposi's sarcoma following chemotherapy for testicular cancer in a homosexual man: demonstration of cytomegalovirus RNA in sarcoma cells 总被引:3,自引:0,他引:3
C M Fenoglio M W Oster P Lo Gerfo T Reynolds R Edelson J A Patterson E Madeiros J K McDougall 《Human pathology》1982,13(10):955-959
A 35-year-old white Jewish homosexual man who had undergone surgery and chemotherapy for an embryonal carcinoma of the testis subsequently developed Kaposi's sarcoma. The neoplasm involved the skin as well as visceral tissues. Tissue derived from a biopsy specimen of one of the skin lesions was used in the in situ hybridization technique for the detection of genetic material. Cytomegalovirus messenger RNA was identified in the neoplastic Kaposi cells in the skin. The significance of this finding is discussed. 相似文献
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Research samples are not often compared to broader community samples to evaluate their representativeness, a critical factor
in determining the generalizability of study findings. This study evaluated the use of voter-registration records for recruiting
a representative sample of community-dwelling, older, and overweight participants for research on improving measures of diet
and physical activity. County voter-registration records were used to identify individuals between 45 and 75 years of age
and living in the two cities closest to the research lab. The data were collected from July, 2007 through November, 2008.
Prospective participants were mailed an introductory letter and opt-out postcard, and received a follow-up recruitment phone
call in which they underwent further screening if interested in participating. The representativeness of the final voter-recruited
sample (N = 191) was evaluated by comparisons of demographic variables with Behavioral Risk Factor Surveillance System (BRFSS) data
at the county and state levels. The voter-recruited sample was only partially comparable to that of the BRFSS sample, with
expected differences in variables related to race/ethnicity, the proportion of women, employment status, and educational attainment.
Voter-registration records are a relatively low-cost ($75 per participant) method of recruiting a community sample that avoids
some biases of other recruitment methods, but may not achieve a fully representative sample. 相似文献
8.
PET/CT image registration: preliminary tests for its application to clinical dosimetry in radiotherapy 总被引:2,自引:0,他引:2
The quality of dosimetry in radiotherapy treatment requires the accurate delimitation of the gross tumor volume. This can be achieved by complementing the anatomical detail provided by CT images through fusion with other imaging modalities that provide additional metabolic and physiological information. Therefore, use of multiple imaging modalities for radiotherapy treatment planning requires an accurate image registration method. This work describes tests carried out on a Discovery LS positron emission/computed tomography (PET/CT) system by General Electric Medical Systems (GEMS), for its later use to obtain images to delimit the target in radiotherapy treatment. Several phantoms have been used to verify image correlation, in combination with fiducial markers, which were used as a system of external landmarks. We analyzed the geometrical accuracy of two different fusion methods with the images obtained with these phantoms. We first studied the fusion method used by the PET/CT system by GEMS (hardware fusion) on the basis that there is satisfactory coincidence between the reconstruction centers in CT and PET systems; and secondly the fiducial fusion, a registration method, by means of least-squares fitting algorithm of a landmark points system. The study concluded with the verification of the centroid position of some phantom components in both imaging modalities. Centroids were estimated through a calculation similar to center-of-mass, weighted by the value of the CT number and the uptake intensity in PET. The mean deviations found for the hardware fusion method were: deltax/ +/-sigma = 3.3 mm +/- 1.0 mm and /deltax/ +/-sigma = 3.6 mm +/- 1.0 mm. These values were substantially improved upon applying fiducial fusion based on external landmark points: /deltax/ +/-sigma = 0.7 mm +/- 0.8 mm and /deltax/ +/-sigma = 0.3 mm 1.7 mm. We also noted that differences found for each of the fusion methods were similar for both the axial and helical CT image acquisition protocols. 相似文献
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Improving the longevity and reliability of cemented total knee arthroplasty remains an important part of orthopaedic research. This paper examines the recently described method of preparation of the cancellous surface of the tibia using suction cannulae in the proximal tibia and stem recess during pulsatile lavage and component fixation. The technique provides a surface clear of debris, fat, blood and marrow, and prevents backflow of blood. A retrospective analysis of post-operative radiographs shows significant improvement in the penetration of cement into the tibial plateau, and improved cement profile towards the periphery. Techniques of stem cementation are also compared, and it is recommended that for this particular design implant, cement should be applied into the cut stem recess in the tibia rather than to the stem of the implant itself. This technique of preparation of the cut surface of the tibia is a simple and, to-date, complication-free method of reliably providing satisfactory cement penetration during total knee arthroplasty. 相似文献
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《Journal of medical engineering & technology》2013,37(2-3):42-51
This paper describes a rationale and methodology for the use if DC recording techniques to reveal patterns of cerebral functional specialization. Results from a number of recent experiments are described. In each of these studies 15 channels of DC potential were recorded from a widely spaced array of scalp-mounted Ag/AgCl electrodes. The duration of single trial recording was always 40 s although the paradigms involved continuous performance of a complex cognitive task. In this series of experiments we used the following tasks: both visually and aurally presented word target detection with classification on a semantic basis, recognition of famous’ faces and discrimination of animal versus non-animal sounds. In each of these tasks the rate of presentation has been systematically varied to evaluate quantitative aspects of task demand. In general, the results from these studies demonstrate that DC recording does provide a method for assessing the degree of activation of different cortical regions at the same time. However. It appears that additional transformation of the data may be required to separate out a number of overlapping slow potentials to increase the sensitivity to more subtle aspects of the cognitive demand. Two different methods to perform the separation are described and applied. 相似文献
11.
Isola AA Schmitt H van Stevendaal U Begemann PG Coulon P Boussel L Grass M 《Physics in medicine and biology》2011,56(18):5925-5947
Large area detector computed tomography systems with fast rotating gantries enable volumetric dynamic cardiac perfusion studies. Prospectively, ECG-triggered acquisitions limit the data acquisition to a predefined cardiac phase and thereby reduce x-ray dose and limit motion artefacts. Even in the case of highly accurate prospective triggering and stable heart rate, spatial misalignment of the cardiac volumes acquired and reconstructed per cardiac cycle may occur due to small motion pattern variations from cycle to cycle. These misalignments reduce the accuracy of the quantitative analysis of myocardial perfusion parameters on a per voxel basis. An image-based solution to this problem is elastic 3D image registration of dynamic volume sequences with variable contrast, as it is introduced in this contribution. After circular cone-beam CT reconstruction of cardiac volumes covering large areas of the myocardial tissue, the complete series is aligned with respect to a chosen reference volume. The results of the registration process and the perfusion analysis with and without registration are evaluated quantitatively in this paper. The spatial alignment leads to improved quantification of myocardial perfusion for three different pig data sets. 相似文献
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Biopsy material of the gingiva obtained from 15 patients with alveolar pyorrhea and 5 persons comprising a control group at the age of 20 to 40 years were investigated by direct immunofluorescent method with the use of labeled fluorescein-isothiocyanatoms of rabbit antisera against IgG and C3 (the third component of compliment) of man, as well as histologically. Clinically, the degree of severity of the lesion was determined by the Russell's index (1956): 0--healthy persons (25%), 1--moderate gingivitis (5%), 2--gingivitis (10%), 6--parodontitis (55%), 8--severe parodontitis (5%). Histologically, mild, moderate, and severe forms of alveolar pyorrhea were singled out. The mild degree of lesion was noted in 30%, moderate--in 15%, and severe--in 45% of patients. The mild form corresponded to 0, 1, and 2, and the severe form--to 6 and 8 according to the Russell's index. In all observations, control including, the presence of IgG in cells of the connective tissue and inside the epithelium was noted. Positive reaction to C3 was observed only in diseased persons, being most pronounced in severe forms of histopathological changes and maximal clinical manifestations. 相似文献
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R S Jones 《Neuroscience letters》1987,81(1-2):209-214
Intracellular recordings from neurones in the medial entorhinal cortex of the rat in vitro showed that the lowest threshold response to stimulation in the subiculum was a long latency, prolonged depolarization, which in extracellular records corresponded to a late, negative DC shift. These responses were reduced or abolished by 2-aminophosphonovalerate suggesting mediation via activation of amino acid receptors of the 'N-methyl-D-aspartate'-type. 相似文献
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Functional CT imaging of angiogenesis in rabbit VX2 soft-tissue tumour. 总被引:31,自引:0,他引:31
Functional parameters such as blood flow (BF), microvessel permeability surface area product (PS), blood volume (BV) and mean transit time (MTT) are physiological markers related to the changes associated with angiogenesis. In the current study we present a functional CT technique for the simultaneous measurement of these four functional parameters and the display of each parameter as a functional image over an entire tissue slice. New Zealand White rabbits with implanted VX2 thigh tumours were scanned using CT with contrast media injection. The ex vivo method of radioactive microspheres was used to evaluate the accuracy of BF measurements with the functional CT technique. There was a significant linear correlation (R = 0.96) between regional CT and microsphere-measured BF values, with a slope not significantly different from unity (0.98 +/- 0.02, P < 0.0001). The precision of our CT technique was determined by the repeated scanning under steady-state conditions. The precision of CT-measured BF, PS. BV and MTT was 14%, 18%, 20% and 24%, respectively. In conclusion, BF can be measured accurately and BF, PS, BV and MTT reproducibly using our functional CT technique. Functional CT can be readily incorporated into existing imaging protocols to assess tumour angiogenesis. 相似文献
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A. A. Bekeshko G. N. Zmievskoi I. B. Kardashova N. D. Minochkina N. V. Rubinskii 《Biomedical engineering》1988,22(5):142-147
Conclusions 1. Within the scope of a qualitative computational model and by experiment it has been shown that the use of monochromatic
radiation for the illumination through an endoscope makes it possible to obtain increased contrast in the image of a pathology
against a background of healthy tissue.
2. The use of a laser as a source of monochromatic radiation is justified in view of the high degree of its monochromaticity
and the spatial directivity which makes it possible to realize the required illumination within the field of view for a narrow
spectral range.
3. The use of single-fiber light guides to carry the laser's radiation through the endoscope's instrumental channel makes
it possible with a monochromatic light to obtain an image of internal cavities with practically any types of endoscope that
have an instrumental channel.
All-Union Scientific-Research Institute of Medical Instrument Making, Moscow. Translated from Meditsinskaya Tekhnika, No.
5, pp. 25–31, September–October, 1988. 相似文献
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A general method for calculating the dose distribution in an irradiated volume is to evaluate the primary and scatter components separately according to the method described by Clarkson and Cunningham. It was found, however, that for a 6 MV Siemens accelerator the calculated dose overestimated the peripheral dose at depths beyond 10 cm by 3%-6%. The difference was attributed to the varying beam quality across the field. This beam quality variation was decreased by hardening the beam with a permanently installed 1/3 in. tungsten filter inserted between the beam flattening filter and the mirror base assembly. The tungsten filter had a more pronounced beam hardening effect at the beam edge than along the central ray. For example, the dose rate in air at the beam edge for a 30 x 30 cm2 field was 13% higher than along the central ray without the tungsten filter. The addition of the 1/8 in. filter decreased this horn to 6%. The beam quality along the central ray also increased. The tissue-air ratio for zero field size along the central ray increased by 2% with the addition of the tungsten filter. The scatter-air ratio, however, did not change with the added filter. Agreement within 1%-2% was achieved between the calculated and measured beam profiles at all depths in a phantom when the tungsten filter was added. 相似文献
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Gloria R. Grice Nicole M. Gattas Jill Sailors Julie A. Murphy Amy Tiemeier Peter Hurd Theresa Prosser Tricia Berry Wendy Duncan 《Patient education and counseling》2013
Objective
To assess whether student pharmacists’ communication skills improved using the Four Habits Model (FHM) at the St. Louis College of Pharmacy.Methods
During the Fall of 2009 and 2010, student pharmacists in the third professional year learned and practiced the FHM. They were given feedback by faculty on three of the four Habits, used the FHM for self and peer assessment, and were formally evaluated on all four Habits during a standardized patient encounter.Results
Student pharmacist performance significantly improved from baseline during both Fall 2009 and Fall 2010 in the majority of the Habits assessed.Conclusion
Use of the FHM in pharmacy education can improve a student pharmacists’ ability to display the four Habits of communicating and developing relationships with patients. Tailoring of the FHM to pharmacy encounters will further enhance the utility of this communication framework.Practice implications
Use of the FHM enhances the measurement and assessment of the relational aspects of student pharmacist–patient communication skills. Consistent use of the FHM over time is likely necessary to fully develop and retain communication skills. The overall goal is to improve patient's health literacy and appropriate medication use by improving communication and the pharmacist–patient relationship. 相似文献18.
Hummel J Figl M Bax M Bergmann H Birkfellner W 《Physics in medicine and biology》2008,53(16):4303-4316
This paper describes a computer-aided navigation system using image fusion to support endoscopic interventions such as the accurate collection of biopsy specimens. An endoscope provides the physician with real-time ultrasound (US) and a video image. An image slice that corresponds to the corresponding image from the US scan head is derived from a preoperative computed tomography (CT) or magnetic resonance image volume data set using oblique reformatting and displayed side by side with the US image. The position of the image acquired by the US scan head is determined by a miniaturized electromagnetic tracking system (EMTS) after calibrating the endoscope's scan head. The transformation between the patient coordinate system and the preoperative data set is calculated using a 2D/3D registration. This is achieved by calibrating an intraoperative interventional CT slice with an optical tracking system (OTS) using the same algorithm as for the US calibration. The slice is then used for 2D/3D registration with the coordinate system of the preoperative volume. The fiducial registration error (FRE) for the US calibration was 2.0 mm +/- 0.4 mm; the interventional CT FRE was 0.36 +/- 0.12 mm; and the 2D/3D registration target registration error (TRE) was 1.8 +/- 0.3 mm. The point-to-point registration between the OTS and the EMTS had an FRE of 0.9 +/- 0.4 mm. Finally, we found an overall TRE for the complete system to be 3.9 +/- 0.6 mm. 相似文献
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