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31.
Ten thrombocytopenic patients (platelets < 10–24 × 10(9)/L) who were refractory to platelet transfusion were investigated for their responsiveness to staphylococcal protein A column therapy. Nine patients had previously been treated with steroids, intravenous immune globulin, and/or other forms of immunosuppressive therapy without improvement in their transfusion response. All patients were receiving multiple platelet transfusions without achieving 1-hour corrected count increments (CCIs) > or = 7500. Eight patients had antibodies that reacted with platelets and were directed against HLA class I antigens, ABO antigens, and/or platelet-specific alloantigens. Plasma (500-2000 mL) from each patient was passed over a protein A silica gel column and then returned to the patient. Patients received from 1 to 14 treatments. A positive response to protein A therapy was defined as at least a doubling of the pretreatment platelet count and/or two successive 10- to 120-minute posttransfusion CCIs > or = 7500. Following plasma treatments, 6 of 10 patients responded with daily platelet counts that averaged 48 +/− 11 × 10(9) per L as compared with counts of 16 +/− 7 × 10(9) per L (p < 0.0005) before treatment. Posttransfusion CCI values determined in four of these patients averaged 2480 +/− 810 and 10,010 +/− 3540 (p < 0.005) before and after treatment, respectively. In contrast, among the four unresponsive patients, platelet counts averaged 10 +/− 9 and 13 +/− 10 × 10(9) per L (p = NS), respectively, while posttransfusion CCIs were 700 +/− 1410 and 1520 +/− 2460 (p = NS), respectively.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
32.
Fleischer AC; Dudley BS; Entman SS; Baxter JW; Kalemeris GC; James AE Jr 《Radiology》1987,162(2):307-310
The depth of myometrial invasion by endometrial carcinoma was evaluated using real-time sonography (US) in 20 patients with histologically proved adenocarcinoma of the endometrium. In 14 of 20 (70%) cases, US-based estimation of the depth of myometrial invasion was within 10% of the actual measurement in the gross specimen. The US-based estimation of tumor invasion was low in seven patients, high in four patients, and agreed with pathologic findings (+/- 5%) in nine patients. In four patients with polypoid intraluminal extension of tumor, a deeply invasive tumor was suspected on US but was not found on pathologic examination. In 12 superficially invasive tumors, the continuity of the demarcating subendometrial halo was intact in nine and incomplete in three. In six patients with deeply invasive tumors, this zone was partially disrupted in four, totally disrupted in one, and intact in one. Errors of estimation of the depth of myometrial invasion on US most frequently occurred when a tumor had a significant intraluminal polypoid extension. Demonstration of a subendometrial halo usually indicated superficial invasion, whereas the absence of a halo was frequently associated with deep invasion. 相似文献
33.
Duplex Doppler ultrasound (US) was used in 68 consecutive patients with focal liver lesions, including 12 hepatocellular carcinomas, one cholangiocarcinoma, 37 metastases, 15 hemangiomas, one hemangioendothelioma, and two focal nodular hyperplasias. Of the hepatocellular carcinomas, six were diffusely hyperechoic, two were hypoechoic, two were single hyperechoic lesions, and two were multifocal and hyperechoic. All ten tumors with Doppler shifts of 5 kHz or above proved to be hepatocellular carcinomas. The other two hepatocellular carcinomas showed Doppler shifts of 3 kHz. In contrast, no hemangioma showed shifts above 0.7 kHz, and ten of the 15 gave no detectable signal. Of the metastases, 20 gave no signal and 17 had signals of up to 4 kHz. Three-kilohertz signals were also obtained from a cholangiocarcinoma, a hemangioendothelioma, and focal nodular hyperplasia. Correlation with angiographic findings suggested that the high-velocity Doppler signals were associated with large pressure gradients due to arteriovenous shunting. Duplex Doppler US can therefore aid in the differential diagnosis of diffuse and focal liver lesions. 相似文献
34.
MJ Hwang A Bhangu CE Webster DM Bowley MX Gannon SS Karandikar 《Annals of the Royal College of Surgeons of England》2014,96(5):343-347
Introduction
In 2009 the Department of Health instructed McKinsey & Company to provide advice on how commissioners might achieve world class National Health Service productivity. Asymptomatic inguinal hernia repair was identified as a potentially cosmetic procedure, with limited clinical benefit. The Birmingham and Solihull primary care trust cluster introduced a policy of watchful waiting for asymptomatic inguinal hernia, which was implemented across the health economy in December 2010. This retrospective cohort study aimed to examine the effect of a change in clinical commissioning policy concerning elective surgical repair of asymptomatic inguinal hernias.Methods
A total of 1,032 patients undergoing inguinal hernia repair in the 16 months after the policy change were compared with 978 patients in the 16 months before. The main outcome measure was relative proportion of emergency repair in groups before and after the policy change. Multivariate binary logistic regression was used to adjust the main outcome for age, sex and hernia type.Results
The period after the policy change was associated with 59% higher odds of emergency repair (3.6% vs 5.5%, adjusted odds ratio [OR]: 1.59, 95% confidence interval [CI]: 1.03–2.47). In turn, emergency repair was associated with higher odds of adverse events (4.7% vs 18.5%, adjusted OR: 3.68, 95% CI: 2.04–6.63) and mortality (0.1% vs 5.4%, p<0.001, Fisher’s exact test).Conclusions
Introduction of a watchful waiting policy for asymptomatic inguinal hernias was associated with a significant increase in need for emergency repair, which was in turn associated with an increased risk of adverse events. Current policies may be placing patients at risk. 相似文献35.
The patterns of cell proliferation and cell migration were studied in three patients with the Sezary syndrome using autoradiographic techniques. Cell labeling patterns following pulse labeling with tritiated thymidine in vivo indicated that Sezary cells proliferate actively in skin and in lymph nodes but that few if any Sezary cells proliferate in the peripheral blood. In two of the patients serial samples were obtained. Label dilution patterns in skin and blood over time suggested that circulating Sezary cells originated in extracutaneous sites where cells were proliferating more rapidly than in the skin. Cells labeled in extracutaneous sites of proliferation appear rapidly in the blood, and their transit time through the peripheral blood compartment is short. Circulating Sezary cells may then be deposited in the skin where they resume proliferation at a low rate. Thus, while Sezary cells proliferate in both cutaneous and extracutaneous sites, proliferation appears to be more rapid in extracutaneous sites such as lymph nodes. This suggests that trials of systemic therapeutic approaches should be undertaken. 相似文献
36.
37.
Roberts JL; Fishman EK; Hartman DS; Sanders R; Goodman Z; Siegelman SS 《Radiology》1986,158(3):613-617
Seven cases of lipomatous masses within the liver parenchyma were demonstrated with computed tomography (CT). Five of these cases were obtained from a retrospective review of 50 cases of renal angiomyolipoma in which the liver was adequately demonstrated. The other two cases were from the files of the Armed Forces Institute of Pathology and had no associated renal lesions. Three of the five cases were associated with tuberous sclerosis. In all seven cases, the fatty tumors appeared on CT scans as a well-defined, 0.8-13-cm mass, with attenuation coefficients of less than -30 HU. On ultrasound studies, the lesions were well circumscribed, highly echogenic, and similar to hemangiomas. While distinctly rare lesions, these lipomatous masses are not as unusual as the literature would indicate. One may anticipate such masses in patients with renal angiomyolipomas and in a relatively high percentage of those with tuberous sclerosis. 相似文献
38.
39.
Michelle M. Mielke Norman J. Haughey Veera Venkata Ratnam Bandaru Steven Schech Richard Carrick Michelle C. Carlson Susumu Mori Michael I. Miller Can Ceritoglu Timothy Brown Marilyn Albert Constantine G. Lyketsos 《Alzheimer's & dementia》2010,6(5):378-385
BackgroundA blood-based biomarker of Alzheimer's disease (AD) would be superior to cerebrospinal fluid (CSF) and neuroimaging measures in terms of cost, invasiveness, and feasibility for repeated measures. We previously reported that blood ceramides varied in relation to timing of memory impairment in a population-based study. The present objective was to examine whether plasma ceramides varied by AD severity in a well-characterized clinic sample and were associated with cognitive decline and hippocampal volume loss over 1 year.MethodsParticipants included 25 normal controls (NC), 17 amnestic Mild Cognitive Impairment (MCI), and 21 early probable AD. A thorough neuropsychological battery and neuroimaging with hippocampal volume determination were conducted at baseline and 1 year later. Plasma ceramides were assayed at baseline using high performance liquid chromatography coupled electrospray ionization tandem mass spectrometry.ResultsAlthough all saturated ceramides were lower in MCI compared with AD at baseline, ceramides C22:0 and C24:0 were significantly lower in the MCI group compared with both NC and AD groups (P < .01). Ceramide levels did not differ (P > .05) in AD versus NC. There were no cross-sectional associations between ceramides C22:0 and C24:0 and either cognitive performance or hippocampal volume among any group. However, among the MCI group, higher baseline ceramide C22:0 and C24:0 levels were predictive of cognitive decline and hippocampal volume loss 1 year later.ConclusionResults suggest that very long-chain plasma ceramides C22:0 and C24:0 are altered in MCI and predict memory loss and right hippocampal volume loss among subjects with MCI. These plasma ceramides may be early indicators of AD progression. 相似文献
40.
Volumetric rendering techniques: applications for three-dimensional imaging of the hip 总被引:1,自引:0,他引:1
Fishman EK; Drebin B; Magid D; Scott WW Jr; Ney DR; Brooker AF Jr; Riley LH Jr; St. Ville JA; Zerhouni EA; Siegelman SS 《Radiology》1987,163(3):737-738
Volumetric rendering is a new approach to three-dimensional (3D) imaging that overcomes many of the drawbacks of currently available surface-rendering systems. Its application on the Pixar Imaging System in two cases of acetabular fracture was assessed to illustrate the features of the technique. The fast-computing architecture and large memory of this system allow rapid generation of a series of high-quality 3D images in each plane of rotation (x or spinal axis, z or somersaulting axis) that can be viewed as independent static images or as an animated real-time video loop. Editing to remove the normal contralateral hemipelvis enhances appreciation of acetabular abnormalities. Every pixel of computed tomographic data is preserved, allowing representation of both soft tissue and bone as translucent overlap. The presentation of data also allows detection of subtle abnormalities and features and minimizes the artifact generation common in surface-rendered images. 相似文献