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81.
82.
Diagnostic impact of core-needle biopsy on fine-needle aspiration of non-Hodgkin lymphoma 总被引:1,自引:0,他引:1
Gong JZ Snyder MJ Lagoo AS Vollmer RT Dash RR Madden JF Buckley PJ Jones CK 《Diagnostic cytopathology》2004,31(1):23-30
We retrospectively reviewed 74 fine-needle aspiration (FNA) cases of presumptive non-Hodgkin lymphoma (NHL). All the cases had cytology and core-needle biopsy and 53 cases had concurrent flow cytometric analysis. FNA (cytology and flow cytometry) and core-needle biopsy were evaluated independently. FNA was diagnostic of diffuse large B-cell lymphoma (DLBL) in 25% (13/53) of cases and small B-cell NHL in 15% (8/53) of cases, whereas core-needle biopsy was diagnostic of DLBL in 37% (27/74) of cases and small B-cell NHL in 8% (6/74) of cases. Subclassification of small B-cell NHL was reached in 3/6 cases by core-needle biopsy. Insufficient cases were observed in both FNA (47%; 25/53) and core-needle biopsy (28%; 21/74) groups. With the combination of FNA and core-needle biopsy, diagnostic cases of DLBL increased to 43% (32/74) and insufficient samples were reduced to 16% (12/74). There was no clear advantage in the diagnosis and classification of small B-cell NHL by adding core-needle biopsy to FNA (14%; 10/74). We conclude that core-needle biopsy is a useful adjunct to FNA in the diagnosis of DLBL and shall be encouraged. In small B-cell NHL, core-needle biopsy does not add to the diagnostic ability of FNA. Cases insufficient for diagnosis may be seen in both core-needle biopsy and FNA. A combined approach reduces the number of insufficient cases and is recommended in routine FNA practice. 相似文献
83.
P W DeVoe R H Buckley L R Shirley C P Darby F E Ward G H Mickey N Raab-Traub G R Vandenbark 《Clinical immunology and immunopathology》1985,34(1):48-59
Cytomegalovirus (CMV) and Epstein-Barr virus (EBV), frequently found in the acquired immune deficiency syndrome (AIDS), have been suspected of contributing to the latter immunodeficiency. The ability of normal HLA-identical sibling bone marrow to reconstitute an 8-month-old infant with severe combined immunodeficiency infected with these two viral agents is of interest. After presentation with severe mucocutaneous candidiasis, cavitary pulmonary disease, nodular cutaneous lesions, and hepatic abscesses containing acid-fast organisms, immunologic studies revealed lymphopenia, 1-3% T cells, and no lymphocyte responses to mitogens. Prior to transplantation, the infant's blood B lymphocytes grew spontaneously in culture, suggesting they were infected with EBV. Indeed, an appropriate antibody response to EBV was detected at 2 months post-transplantation. At 3 weeks postgrafting, neutropenia and cholestatic jaundice developed without other signs of graft versus host disease. Liver biopsy demonstrated CMV but no EBV by DNA hybridization. There was evidence of T- and B-cell function by 2 weeks postgrafting, including vigorous in vivo and in vitro responses to candida. Although the blood lymphocyte T4:T8 ratio was inverted at 2 weeks, it reverted to normal by 6 weeks post-transplantation. All clinical disease resolved by 8 months and karotyping revealed all T and B lymphocytes to be XX. Thus, despite infections with both CMV and EBV, complete immunologic reconstitution was achieved in this, the most severe of all genetically determined immunodeficiency conditions, arguing against these viruses having a major role in the failure of bone marrow transplantation in AIDS. 相似文献
84.
Since the mid 196O's there has hcen a growing interest in and use of computers in psychophysiology laboratories. There are even a growing number of accepted physiological measures which are fully dependent on computer technology for their derivation. Although minicomputers have been in use for over a decade, recent developments in microcomputer and microprocessor technology have led to rapid acceptance of microcomputers for laboratory work. These rapid advances have produced a need to survey the current state of laboratory computer applications and development. A comprehensive survey was mailed to 301 psychophysiology laboratory groups during the spring and summer of 1979 and completed surveys were received from 61% of the mailing. Sun'ey results are reported on computer hardware and configuration, dependent measures and user satisfaction, and use and cost of engineering and programming support. Developments in computer hardware and user services are also discussed. 相似文献
85.
CSnrc, a new user-code for the EGSnrc Monte Carlo system is described. This user-code improves the efficiency when calculating ratios of doses from similar geometries. It uses a correlated sampling variance reduction technique. CSnrc is developed from an existing EGSnrc user-code CAVRZnrc and improves upon the correlated sampling algorithm used in an earlier version of the code written for the EGS4 Monte Carlo system. Improvements over the EGS4 version of the algorithm avoid repetition of sections of particle tracks. The new code includes a rectangular phantom geometry not available in other EGSnrc cylindrical codes. Comparison to CAVRZnrc shows gains in efficiency of up to a factor of 64 for a variety of test geometries when computing the ratio of doses to the cavity for two geometries. CSnrc is well suited to in-phantom calculations and is used to calculate the central electrode correction factor Pcel in high-energy photon and electron beams. Current dosimetry protocols base the value of Pcel on earlier Monte Carlo calculations. The current CSnrc calculations achieve 0.02% statistical uncertainties on Pcel, much lower than those previously published. The current values of Pcel compare well with the values used in dosimetry protocols for photon beams. For electrons beams, CSnrc calculations are reported at the reference depth used in recent protocols and show up to a 0.2% correction for a graphite electrode, a correction currently ignored by dosimetry protocols. The calculations show that for a 1 mm diameter aluminum central electrode, the correction factor differs somewhat from the values used in both the IAEA TRS-398 code of practice and the AAPM's TG-51 protocol. 相似文献
86.
Kucharczyk W; Brant-Zawadzki M; Lemme-Plaghos L; Uske A; Kjos B; Feinberg DA; Norman D 《Radiology》1985,157(1):95-101
In multiple spin-echo image sequences of blood flow, the "even-echo" phenomenon produces an absolute increase in signal magnitude from first- to second-echo images of normal vessels harboring slow flow. Distinguishing this from the apparent relatively high signal intensity seen on second-echo images in pathologic foci of stationary tissue is important to the diagnostician. Selected case material containing two tissue types was reviewed retrospectively: tissues known to harbor slow flow, such as normal veins and venous sinuses and vascular malformations, and tissues that have long transverse (T2) relaxation times and appear as intense structures on second-echo images, such as neoplasms, infarcts, and regions of demyelination. Calculations of T2 parameters were made by computer for defined regions of interest. T2 images were also generated. Visual inspection of the acquired images did not reliably distinguish increased intensity due to even-echo rephasing from the relative changes between adjacent tissues seen on second-echo images. More definitive differentiation of the even-echo phenomenon was provided by calculated values of T2 and computer-synthesized T2 images representing acquired intensity data of two-echo sequences. The synthesized images were especially useful when stationary tissue with lengthened T2 values was adjacent to or in proximity to vessels or vascular lesions. A five spin-echo image sequence was valuable for separating slow flow from stationary tissue by a technique of synthesizing T2-difference images using three consecutive echoes. 相似文献
87.
Russell EJ; Geremia GK; Johnson CE; Huckman MS; Ramsey RG; Washburn-Bleck J; Turner DA; Norusis M 《Radiology》1987,165(3):609-617
Sixteen patients with suspected cerebral metastases were studied with magnetic resonance (MR) imaging before and after the intravenous administration of 0.1 mmol/kg of gadolinium diethylenetriaminepenta-acetic acid. The images were interpreted blindly by two neuroradiologists; all clinical, radiologic (computed tomographic and MR imaging), and pathologic data were reviewed to arrive at a final "best diagnosis," which was then compared with the prior blinded interpretations. Of seven patients found to have multiple metastases, six (86%) had at least one tumor nodule depicted by postinfusion MR imaging that was missed by one or both observers on review of preinfusion images alone. Lesions missed on preinfusion studies were usually small nodules hidden by or not detected next to regions of high-signal edema thought to be related to the adjacent tumor nodule. The authors believe that contrast enhancement improves detection of metastatic foci with MR imaging and that the findings indicate broader implications for the detection of multiple lesions from other causes. 相似文献
88.
目的:通过对骨髓单个核细胞在体外与不同细胞因子培养,了解不同细胞因子对骨髓淋巴细胞的激活能力和对骨髓干祖细胞的损伤情况。方法:将IL-1、IL-2、γ-IFN、CD3单抗进行不同组合后,在体外与骨髓单个核细胞分成对照组、IL-2组、CD3-AK、CIK组进行培养。培养过程中观察细胞形态和数量的变化,并在培养后检测免疫活性细胞的细胞毒性和造血干细胞的保存情况。结果:培养过程中对照组细胞数量减少;IL-2组细胞数量变化不明显;CD3-AK组、CIK组细胞数量显著增多,并出现较多的集聚成簇的淋巴样细胞,培养后其细胞毒性明显强于对照组及IL-2组,但细胞数量增加和细胞毒性无明性差异,培养后各组造血干细胞保存情况约16%~87%。结论:IL-2、CD3单抗在体外与骨髓单个核细胞培养后,即能激活免疫细胞增殖,又能保留足够的造血干细胞。 相似文献
89.
90.
H F Seigler W W Shingleton R S Metzgar C E Buckley P M Bergoc D S Miller B F Fetter M B Phaup 《Surgery》1972,72(1):162-174