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61.
A rat model of monitoring liver allograft rejection 总被引:5,自引:0,他引:5
Timi Martelius Heikki Mäkisalo Krister Höckerstedt Eero Taskinen Irmeli Lautenschlager 《Transplant international》1997,10(2):103-108
Rat models are often used to study liver allograft rejection. We have established a model for rat liver allograft rejection,
monitored by fine needle aspiration biopsy (FNAB), in the strain combination PVG-to-BN with a mean survival time of 37 ± 20
days. In this model, we observed acute rejection with an intense peak of lymphoid blasts and lymphocyte-dominated inflammation
in the FNAB [9.1 ± 3.0 corrected increment units (CIU)], and an eventual increase in macrophages (up to 4.2 ± 4.4 CIU), together
with fibrosis and parenchymal necrosis in the graft. Markers of immune activation, such as an increase in IL-2-receptor (from
1 % ± 2 % to 21 % ± 13 %) and class II (from 20 % ± 9 % to 43 % ± 13 %) expressing lymphoid cells and induction of ICAM-1
in the graft, were consistent with the overall cellular response. The FNAB correlated well with parallel graft histology.
In this rat model, the atraumatic monitoring makes a close follow-up possible without having to sacrifice the experimental
animals. This saves work, animals, and costs in the study of liver rejection.
Received: 2 July 1996 Accepted: 28 October 1996 相似文献
62.
J. G. Boonstra Johan W. van der Pijl Yves F. C. Smets Herman H. P. J. Lemkes Jan Ringers Leendert A. van Es F. J. van der Woude Jan A. Bruijn 《Transplant international》1997,10(6):451-456
To examine the incidence of interstitial and vascular
rejection in pancreas allografts and its impact on graft survival, we studied 36 percutaneous pancreas biopsies and 10 pancreas
transplantectomy specimens from 32 patients who had undergone simultaneous pancreas-kidney transplantation. Interstitial rejection
(IR) was predominantly found in the biopsies, while vascular rejection (VR) was most prominent in the transplantectomies.
Pancreas graft survival was significantly decreased for pancreas grafts that had suffered from vascular rejection when compared
to those with only interstitial rejection. Potential rejection markers, i. e., serum amylase, glucose, creatinine, and urinary
amylase, did not correlate with histological signs of rejection, although increased levels of serum amylase were, in all but
one case, associated with rejection.We conclude that a percutaneous pancreas biopsy remains the most reliable method to determine
pancreas rejection, and that by distinguishing between IR andVR, a pancreas biopsy may provide important diagnostic as well
as prognostic information.
Received: 6 March 1997 Received after revision: 5 June 1997 Accepted: 30 June 1997 相似文献
63.
人乳头瘤病毒感染的多灶性的临床分析 总被引:10,自引:0,他引:10
对176例外阴尖锐湿疣患者的子宫颈进行检测,以诊断是否同时伴有人乳头状瘤病毒(HPV)感染。结果:肉眼观察诊断宫颈HPV感染23例(13%),阴道镜诊断146例(83%),宫颈活检病理诊断112例(64%),其中合并宫颈上皮内瘤变(CIN)1 ̄2级32例(18%)。结果提示:(1)外阴尖锐湿疣患者子宫颈伴有HPV感染和/或亚临床感染相当常见。(2)借助阴道镜取宫颈活检是诊断宫颈HPV感染的常用方法 相似文献
64.
Lorenzo E. Derchi Carlo Martinoli Roberto Pontremoli Stefano Saffioti Caterina Pastorino 《European radiology》1993,3(2):186-189
Two patients with arteriovenous fistulas of the native kidney occurring after needle biopsy were evaluated using duplex and color Doppler ultrasonography. The first patient had a fistula with associated pseudoaneurysm: color Doppler showed the lesion as a small rounded area with whirling flow; spectral analysis allowed recognition of both the afferent artery with low impedance flow and the draining vein with pulsatile, arterialized flow. The second patient had a normal color Doppler study; however, spectral analysis demonstrated signals with low vascular impedance from an intra-parenchymal artery at the lower pole, and a jet of turbulent flow. Following disappearance of clinical findings, such Doppler abnormalities were no longer detectable. When a iatrogenic arteriovenous fistula is considered on clinical grounds, both color and Doppler spectral analysis of waveforms from intra-parenchymal vessels should be performed. Possibly, further advances in color Doppler technology will permit the use of this examination as the first imaging procedure in these clinical situations.Correspondence to: L. E. Derchi 相似文献
65.
Maite Sainz De La Maza Ramzy K. Hemady C. Stephen Foster 《Documenta ophthalmologica. Advances in ophthalmology》1993,83(1):33-41
While systemic autoimmune diseases are the main possibilities in the differential diagnosis of scleritis, other less common etiologies such as infections must also be considered. The authors report four cases of infectious scleritis to review predisposing factors, clinical characteristics, methods of diagnostic approach, and response to therapy. Two patients had primary scleritis and two patients had secondary scleritis following extension of primary corneal infection (corneoscleritis). Diagnoses included three local infections (one each withStaphylococcus. Acanthamoeba, and herpes simplex) and one systemic infection (Lyme disease). Stains, cultures, or immunologic studies from scleral, conjunctival, and/or corneal tissues, and serologic tests were used to make the diagnosis. Medical therapy, including antimicrobial agents, was instituted in all patients, and surgical procedures were additionally required in two patients (scleral grafting in one and two penetrating keratoplasties in another); the patient who required two penetrating keratoplasties had corneoscleritis and underwent eventual enucleation. Infectious agents should be considered in the differential diagnosis of scleritis. 相似文献
66.
CT导引下胸部病变穿刺活检影响诊断正确率因素分析 总被引:4,自引:0,他引:4
目的 :探讨影响CT导引下胸部病变穿刺活检诊断正确率的因素。方法 :复习有手术病理、临床和影像学随访的胸部病变CT导引下穿刺活检 2 4 4例 ,依据手术病理、治疗反应及临床随访结果对活检病灶作出最终诊断 ,观察因素包括患者相关因素 (性别、年龄、有无肺气肿 )、病灶相关因素 (病灶大小、位置、有无空腔及病灶深度 )和操作相关因素 (患者的体位 )。结果 :胸部病变CT导引下穿刺活检诊断正确率为 82 .4 % ( 2 0 1 /2 4 4)。活检诊断正确率与病灶大小有关 ,诊断正确组和非正确组病灶大小分别为 3 .97± 1 .80cm和 3 .1 1± 1 .4 4cm(P <0 .0 5 )。患者性别、年龄、有无肺气肿、病灶位置、深度、有无空腔及患者体位对穿刺活检诊断正确率的影响无统计学意义。结论 :病灶大小是影响CT导引下胸部病变穿刺活检诊断正确率的主要因素 相似文献
67.
CT引导下经皮穿刺活检对纵隔占位病变的诊断价值 总被引:6,自引:0,他引:6
目的评价CT引导下经皮穿刺活检术在纵隔占位病变中的应用价值和安全性。方法采用弹簧式自动活检枪,在CT精确定位下对纵隔内占位病变行经皮穿刺活检,所获标本送病理组织学检查,并对穿刺准确性、病理确诊率和并发症发生情况进行分析。结果本组33例病灶穿刺成功率100%,病理确诊率85%,无一例发生并发症。结论CT引导下经皮穿刺活检术是一项操作方便,定位精确,穿刺准确率和病理确诊率高,安全可靠的介入放射诊断技术,对纵隔占位病变的定性诊断很有价值,值得临床推广应用。 相似文献
68.
Robert C Susil Kevin Camphausen Peter Choyke Elliot R McVeigh Gary S Gustafson Holly Ning Robert W Miller Ergin Atalar C Norman Coleman Cynthia Ménard 《Magnetic resonance in medicine》2004,52(3):683-687
A technique for transperineal high-dose-rate (HDR) prostate brachytherapy and needle biopsy in a standard 1.5 T MRI scanner is demonstrated. In each of eight procedures (in four patients with intermediate to high risk localized prostate cancer), four MRI-guided transperineal prostate biopsies were obtained followed by placement of 14-15 hollow transperineal catheters for HDR brachytherapy. Mean needle-placement accuracy was 2.1 mm, 95% of needle-placement errors were less than 4.0 mm, and the maximum needle-placement error was 4.4 mm. In addition to guiding the placement of biopsy needles and brachytherapy catheters, MR images were also used for brachytherapy treatment planning and optimization. Because 1.5 T MR images are directly acquired during the interventional procedure, dependence on deformable registration is reduced and online image quality is maximized. 相似文献
69.
E. Stermer J. Bejar† I. Miselevich† O. Goldstein D. Keren A. Lavy J. H. Boss† D. Keren 《Colorectal disease》2005,7(4):345-349
BACKGROUND: Total excision of colonic polyps is not always attainable and in some patients it is clinically contraindicated. Also, a resected polyp may be lost at any step between its endoscopic removal and its embedding in paraffin. The aim of this study was to compare the histological features of colonic polyps as analysed by the study of biopsy-forceps obtained samples with those assessed on scrutinizing the totally resected growths. PATIENTS AND METHODS: This prospective study included a cohort of 59 patients in whom, in the course of an elective colonoscopy, a total excision of a 6 mm-sized or larger polyp was called for. Sizeable biopsies were obtained by means of an Olympus Multibyte forceps prior to the total polypectomy. Subsequent to the study of the polypectomy specimens, the forceps biopsy samples were submitted for histological examination. The pathologists were blinded as to the source of the tissue they were studying. The diagnoses rendered by evaluating the biopsy samples and polypectomy specimens of each patient were contrasted with each other. RESULTS: Major discrepancies between the histological features of the fragments captured by the biopsy-forceps and the factual nature of the totally removed polyps were uncovered in 11 (18.6%) of 59 cases. Intriguingly, the grade of the tumours was underrated in all the 11 cases, as judged by contrasting the tentative diagnoses of the forceps-biopsies with the decisive diagnoses of the polypectomies. Importantly, 2 adenocarcinomas would have been missed by just looking at the forceps-retrieved sample. CONCLUSIONS: In our experience, a discordance of 18.6% is to be expected between the diagnoses rendered after examining forceps-biopsies of and totally excised colonic polyps. Nevertheless, it is advisable to procure biopsies prior to the excision of the growths, because on those occasions in which patients' growths cannot be removed or have not been retrieved for one reason or another, a small forceps-captured tissue sample correctly reflects the characteristics of the polyp in 81.4% of the cases. Finally, the biopsies may be discarded in the event that total removal was successful. 相似文献
70.