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41.
42.
Cutaneous T cell lymphoma: characterization by monoclonal antibodies 总被引:10,自引:0,他引:10
Monoclonal antibodies to human T cells permit the characterization of the surface phenotype of cutaneous T cell lymphoma (CTCL). The majority of CTCL cells are reactive with OKT1 and OKT3 monoclonals, which identify peripheral T cells and mature thymocytes. The neoplastic cells also react with OKT4, which recognizes the inducer T cell subset; they are, however, unreactive with OKT5 monoclonal, which identifies cytotoxic/suppressor T cell subsets. These data are in agreement with previous functional studies demonstrating that CTCL is a neoplasm of inducer (helper) T cells. 相似文献
43.
Membrane fluidity changes accompanying phagocytosis in normal and in chronic granulomatous disease polymorphonuclear leukocytes 总被引:2,自引:0,他引:2
We have studied membrane fluidity changes in polymorphonuclear leukocytes (PMN) during phagocytosis. Membrane fluidity was assessed by electron spin resonance (ESR) using a nitroxide-substituted stearic acid analog (5DS) as a spin probe. PMN from normal subjects and from 3 CGD patients (2 males, 1 female) were incubated in Kreb's Ringers phosphate with or without opsonized zymosan. ESR spectra were obtained and the order parameter (S), which is inversely related to membrane fluidity, was calculated. Without zymosan addition, S for normal (0.638) and for CGD (0.635) were not significantly different (p less than 0.35). The S values indicate that under resting conditions the molecular environment of the CGD membrane is similar to that of normal PMN membranes. However, with addition of opsonized zymosan, the normal, but not the CGD, PMN showed a significant increase (CGD, S = 0.638; normal, S = 0.647; p less than 0.001). This change in S for the normals is consistent with a more restricted movement of 5DS. Treatment of normal PMN with a mixture of scavengers specific for H2O2 (catalase, 1600 U/ml), O2-.(superoxide dismutase, 100 micrograms/ml), and for HO., (sodium benzoate, 1mM) during zymosan stimulation gave S values similar to those of resting cells. Catalase alone also lowered S value, suggesting that H2O2 was instrumental in causing the initial S value increase. This idea was supported by studies in which CGD cells were incubated with zymosan in the presence of glucose oxidase, an enzyme that catalyzes glucose oxidation resulting in the direct reduction of molecular oxygen to H2O2. Our results indicate that reduced O2 by- products, particularly H2O2, can cause altered biophysical properties of PMN membrane during phagocytosis. 相似文献
44.
45.
Armato SG Oxnard GR Kocherginsky M Vogelzang NJ Kindler HL MacMahon H 《Academic radiology》2005,12(10):1301-1309
RATIONALE AND OBJECTIVES: To evaluate the clinical acceptability of semiautomated methods for the measurement of mesothelioma tumor thickness in computed tomography (CT) scans. MATERIALS AND METHODS: A computer interface was developed to allow the acquisition of semiautomated mesothelioma tumor thickness measurements, which require the manual selection of a point along the outer margin of the tumor in a CT section. After application of an automated lung segmentation method, the computer automatically identifies a corresponding point along the inner margin of the tumor (as represented by the lung boundary), constructs a line segment between the manually selected outer tumor margin point and the computer-determined inner tumor margin point, and computes tumor thickness as the length of this line segment. Three radiologists and oncologists independently reviewed line segments representing the semiautomated measurements generated by three different algorithms at 134 measurement sites in the CT scans of 22 mesothelioma patients. The observers either accepted a measurement line segment or modified it through the interface. Differences between the initial semiautomated measurements and the measurements as modified by the observers were analyzed. RESULTS: The frequency with which observers accepted the semiautomated measurements without modification was as high as 86%. Of all measurements across all observers and methods (1,206 measurements), 89% were changed by 2 mm or less. CONCLUSION: We have developed semiautomated methods to measure mesothelioma tumor thickness. The potential of these methods has been demonstrated through an observer study. We expect these methods to become important tools for the efficient quantification of tumor extent. 相似文献
46.
Ryu RK Omary RA Sichlau MJ Siddiqi A Chrisman HB Nemcek AA Vogelzang RL 《Cardiovascular and interventional radiology》2003,26(4):375-378
When compared in a uterine artery embolization
(UAE) animal model, Embospheres (ES) (Biosphere Medical, Rockland, MA)
were found to induce less uterine ischemia than polyvinyl alcohol (PVA)
particles. Given this finding, we aimed to test the hypothesis that ES
is associated with less pain after UAE than PVA in human patients. We
performed retrospective analysis on data from 72 consecutive UAE
patients, collected from a prospectively acquired database.
Patient-controlled analgesia (PCA) pump-delivered morphine sulfate (MS)
dosages were compared between patients who received ES versus PVA.
Subjective pain scores (SPS) were also compared between the two groups.
Secondary outcome measures, including embolic volume and clinical
outcome data, were also collected. Linear regression and t-test
statistical analyses were performed. Null hypotheses were rejected at
the p < 0.05 level. Mean follow-up period in the PVA
population was 178 days (range 28–426), versus 96 days (range 24–197)
in the ES population. The mean MS doses used by ES and PVA patients
were 37.2 (s.d. 23.5) versus 47.1 (s.d. 26.8), respectively. This
difference was not significant (p > 0.15).
Utilizing a standard 0–10 pain scale, the mean peak SPS for the ES and PVA groups were 5.58 (s.d. 2.77) and 5.07 (s.d. 2.99), respectively.
The difference was not significant. The mean amount of embolic material
used in each ES and PVA patient was 4.86 cc (s.d. 3.01) and 3.52 cc
(s.d. 1.63), respectively. The difference revealed a strong trend
toward statistical significance (p = 0.05). There was one treatment failure in each group of patients. Within both patient
samples, no significant correlation was found when comparing the volume
of embolic used and subsequent MS dose. Despite a strong trend toward a
significantly higher volume of ES used per patient, there is no
subjective or objective difference in pain after UAE with ES when
compared to PVA. 相似文献
47.
Daniel P. Petrylak MD Nicholas J. Vogelzang MD Kamal Chatta MD Mark T. Fleming MD David C. Smith MD Leonard J. Appleman MD PhD Arif Hussain MD Manuel Modiano MD Parminder Singh MD Scott T. Tagawa MD Ira Gore MD Edward F. McClay MD Anthony E. Mega MD A. Oliver Sartor MD Bradley Somer MD Raymond Wadlow MD Neal D. Shore MD William C. Olson PhD Nancy Stambler DrPH Vincent A. DiPippo PhD Robert J. Israel MD 《The Prostate》2020,80(1):99-108
48.
Surface shield: device to reduce personnel radiation exposure 总被引:2,自引:0,他引:2
Young AT; Morin RL; Hunter DW; Nelson KL; Cardella JF; Castaneda-Zuniga WR; Amplatz K 《Radiology》1986,159(3):801-803
A simple device is described that can reduce personnel exposure from scatter radiation by up to 75%. The device consists of an oblong piece of shielding (0.75-mm lead equivalent) that is taped to the side of the patient during percutaneous renal stone removal and other interventional procedures. Contrary to other shields and barriers, this does not interfere with access to the patient. Scatter exposure data from phantom studies are presented and the rationale for surface shielding discussed. 相似文献
49.
BACKGROUND: Institution of early hormone therapy in the PSA era coupled with demonstration of clinical benefit with chemotherapy in hormone refractory prostate cancer (HRPC) and acceptance of PSA decline as a surrogate for response has resulted in introduction of chemotherapy earlier in the natural history of disease. There now exists a need to identify, effective agents for second line chemotherapy. 9-nitrocamptothecin (9-NC) a novel, oral camptothecin analogue was tested as second line chemotherapy for patients with progressive hormone refractory prostate cancer. PATIENTS AND METHODS: Eligible patients had metastatic hormone refractory prostate cancer with performance status (0-1) following progression on at least 1 prior cytotoxic chemotherapy. 9-NC was administered orally at the dose of 1.5 mg/m2/d for 5 days each week for 3 weeks, followed by rest for 1 week. Response was evaluated after 2 cycles according to the guidelines set forth for Phase II trials in HRPC by the PSA working group. RESULTS: Thirty-five patients were recruited to the study within a period of 6 months; 33 were evaluable for analysis. No patients had a >50% decline in PSA levels. Two out of 8 (25%) patients with measurable disease and 5/25 (20%) patients with nonmeasurable disease showed stable disease. The median time to disease and PSA progression was 2 months [95% confidence interval (CI), 0.9-2.8]. The median overall survival was 10 months (95% CI = 5-12). Seven patients are alive after a median follow-up of 23 months. CONCLUSIONS: 9-nitrocamptothecin failed to elicit clinical or PSA responses. Further study in pretreated HRPC patients is not warranted. 相似文献
50.
Sclerosing cholangitis: CT findings 总被引:5,自引:0,他引:5
The value of computed tomography (CT) in the detection of primary sclerosing cholangitis (PSC) in the intrahepatic and extrahepatic biliary systems was assessed by comparing CT scans of 20 cases of PSC with cholangiographic findings. In 16 of 19 cases of extrahepatic duct disease demonstrated with cholangiography, CT demonstrated abnormalities of the common hepatic duct, or bile duct, including duct stenosis, mural nodularity, duct dilatation, wall thickening, and mural enhancement. CT demonstrated intrahepatic disease in all 20 cases, including duct dilatation, duct stenosis, pruning, and beading. CT was superior to cholangiography in characterization of the status of the intrahepatic duct system in 11 of 20 cases. In addition, CT demonstrated extrabiliary complications of PSC in 12 cases and superimposed cholangiocarcinoma in three cases. While cholangiography remains the standard for diagnosis and follow-up of PSC, CT can provide valuable information about the extent and complications of the disease. 相似文献