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1.
活体移植肾脏的OCT光学监测新技术   总被引:2,自引:2,他引:0  
肾脏移植是救治终末期肾病(ESRD,end-stage re nal disease)患者的最佳方法。缺血造成的急 性肾小管坏死(ATN,acute tubular necrosis)是导致受体移植肾脏功能延迟恢复(DGF,d elayed graft function)和肾脏移植失败的主要因素。目前还没有一种能够准确地判定供 体肾脏是否发生ATN的无损方法。光学相干层析成像术(OCT)是一种新兴的医学成像技 术,可以对生物组织微小结构进行实时无损高分辨率成像。本文对肾脏移植过程中的光学相 干成像评估活体移植肾脏活性的新方法和技术做一综述。  相似文献   

2.
In this paper, we focus on segmentation of ultrasound kidney images. Unlike previous work by using trained prior shapes, we employ a parametric super-ellipse as a global prior shape for a human kidney. The Fisher–Tippett distribution is employed to describe the grey level statistics. Combining the grey level statistics with a global character of a kidney shape, we propose a new active contour model to segment ultrasound kidney images. The proposed model involves two subproblems. One subproblem is to optimize the parameters of a super-ellipse. Another subproblem is to segment an ultrasound kidney image. An alternating minimization scheme is used to optimize the parameters of a super-ellipse and segment an image simultaneously. To segment an image fast, a convex relaxation method is introduced and the split Bregman method is incorporated to propose a fast segmentation algorithm. The efficiency of the proposed method is illustrated by numerical experiments on both simulated images and real ultrasound kidney images.  相似文献   

3.
In this paper, an effective model-based approach for computer-aided kidney segmentation of abdominal CT images with anatomic structure consideration is presented. This automatic segmentation system is expected to assist physicians in both clinical diagnosis and educational training. The proposed method is a coarse to fine segmentation approach divided into two stages. First, the candidate kidney region is extracted according to the statistical geometric location of kidney within the abdomen. This approach is applicable to images of different sizes by using the relative distance of the kidney region to the spine. The second stage identifies the kidney by a series of image processing operations. The main elements of the proposed system are: 1) the location of the spine is used as the landmark for coordinate references; 2) elliptic candidate kidney region extraction with progressive positioning on the consecutive CT images; 3) novel directional model for a more reliable kidney region seed point identification; and 4) adaptive region growing controlled by the properties of image homogeneity. In addition, in order to provide different views for the physicians, we have implemented a visualization tool that will automatically show the renal contour through the method of second-order neighborhood edge detection. We considered segmentation of kidney regions from CT scans that contain pathologies in clinical practice. The results of a series of tests on 358 images from 30 patients indicate an average correlation coefficient of up to 88% between automatic and manual segmentation.  相似文献   

4.
目的探讨肾移植术后重症肺部感染的护理。方法对45例肾移植术后发生重症肺部感染患者采取专科护理、心理疏导,同时加强药物管理及综合治疗。结果肾移植术后重症肺部感染患者45例,治愈32例,总治愈率71.1%,死亡13例(其中6例放弃治疗),总死亡率28.9%。结论肾移植术后肺部感染多发生于术后6个月内,病原体呈多样性,合并症出现较多,病情进展快,死亡率较高,对此类患者需在基本护理基础上强化无菌操作和消毒隔离。  相似文献   

5.
This paper presents a three-dimensional (3-D) shape reconstruction/intrapatient rigid registration technique used to establish a Nephron-Sparing Surgery preoperative planning. The usual preoperative imaging system is the Spiral CT Urography, which provides successive 3-D acquisitions of complementary information on kidney anatomy. Because the kidney is difficult to demarcate from the liver or from the spleen only limited information on its volume or surface is available. In this paper, we propose a methodology allowing a global kidney spatial representation on a spherical harmonics basis. The spherical harmonics are exploited to recover the kidney 3-D shape and also to perform intrapatient 3-D rigid registration. An evaluation performed on synthetic data showed that this technique presented lower performance then expected for the 3-D shape recovering but exhibited registration results slightly more accurate as the iterative closest point technique with faster computation time.  相似文献   

6.
Kidney transplantation is typically the most effective treatment for patients with end-stage renal disease. However, the supply of kidneys is far short of the fast-growing demand. Kidney paired donation (KPD) programs provide an innovative approach for increasing the number of available kidneys. In a KPD program, willing but incompatible donor-candidate pairs may exchange donor organs to achieve mutual benefit. Recently, research on exchanges initiated by altruistic donors (ADs) has attracted great attention because the resultant organ exchange mechanisms offer advantages that increase the effectiveness of KPD programs. Currently, most KPD programs focus on rule-based strategies of prioritizing kidney donation. In this paper, we consider and compare two graph-based organ allocation algorithms to optimize an outcome-based strategy defined by the overall expected utility of kidney exchanges in a KPD program with both incompatible pairs and ADs. We develop an interactive software-based decision support system to model, monitor, and visualize a conceptual KPD program, which aims to assist clinicians in the evaluation of different kidney allocation strategies. Using this system, we demonstrate empirically that an outcome-based strategy for kidney exchanges leads to improvement in both the quantity and quality of kidney transplantation through comprehensive simulation experiments.  相似文献   

7.
It is established that the preparation K-2-9 being administered in combination with cis-dichlorodiaminoplatinum (DDP) lowers the DDP toxic effects, in particular nephrotoxicity and enterotoxicity, increases the activity of the enzymes participating in microsomal liver oxidation, the activity of kidney transamidinase, the quantity of SH-groups of the liver and kidney tissue, intensifies the antitumour effect of DDP.  相似文献   

8.
毒黄素对小鼠肾脏毒性作用的超微病理观察   总被引:1,自引:0,他引:1  
观察毒黄素对小鼠肾脏的超微病理改变,探讨毒黄素中毒的机理。小鼠腹腔注射毒黄素(1.5 mg/kg),2 h后取其肾皮质,应用电子显微镜观察其超微结构改变。电镜下可查见毒黄素主要损伤肾近曲小管上皮细胞的线粒体和毛细血管内皮细胞基底膜,表现为大量线粒体空泡化和毛细血管基底膜不匀性增厚。毒黄素可造成肾近曲小管上皮细胞和肾小球毛细血管内皮细胞的超微结构损伤,以线粒体和基底膜的损伤更为突出,为毒黄素的毒性作用提供超微形态学依据。  相似文献   

9.
目的探讨歼(强)击机飞行员肾结石的诊断治疗及医学鉴定原则。方法回顾分析1982年-2008年43名患肾结石的歼(强)击机飞行员病史资料、诊治过程及医学鉴定结论。结果23名肾结石飞行员经治疗结石排出,4例确诊为肾钙化,均飞行合格;3人因结石长期治疗无效予以停飞,1人因其他疾病停飞;12例处于治疗、观察期,结论为飞行暂不合格。结论歼(强)击机飞行员(含飞行教员)患肾结石影响飞行安全,应在结石排出后方可恢复飞行远离集合系统的肾钙化灶可放飞,但应定期复查,掌握其变化情况。  相似文献   

10.
Fenosan has been studied for its effect on the lipid peroxidation level of mitochondria and microsomes of the rat kidneys in different periods of nitrosodimethylamine-induced carcinogenesis as well as on the incidence of kidney tumour formation. A month after the treatment with the above carcinogen the lipid peroxidation in the rat kidney was activated. An additional injection of fenosan decreased the intensity of the lipid peroxidation and inhibited the tumour development in kidneys. It is supposed that anticarcinogenic action of fenosan is related to the membrane protection from the lesion by the carcinogen.  相似文献   

11.
目的探讨抗淋巴细胞血清(ALS)联合他克莫司(FK506)在诱导大鼠肾脏移植免疫耐受中的作用。方法以SD大鼠作为供体,Wistar大鼠作为受体,建立大鼠肾移植模型。对照组(A组)仅行肾移植,术前术后未予免疫干预;ALS组(B组)术后当天腹腔注射ALS,连续应用至术后第10天;FK506组(C组)术后当天开始应用FK506,连续应用至术后第10天;联合组(D组)联合应用ALS与FK506。术后观测各组受者存活时间、移植肾功能、移植肾血供、免疫耐受状态等。结果D组平均存活时间为(37.0±5.3)d,与A组(7.4±1.6)d、B组(16.3±4.7)d及C组(17.5±5.3)d比较,差异均有统计学意义(P<0.05);手术后1周检查A组移植肾血供差,平均肾血管阻力指数0.80±0.06;B组和C组移植肾血供良好,平均阻力指数分别为0.62±0.07、0.63±0.08;D组移植肾血供良好,术后1周与术后20d平均阻力指数分别为0.61±0.04、0.62±0.03;D组与A组相比较差异有统计学意义(P<0.05)。结论ALS联合FK506能够延长受者存活时间和促进免疫耐受的诱导。  相似文献   

12.
13.
It is important to predict the tumor growth so that appropriate treatment can be planned in the early stage. In this letter, we propose a finite-element method (FEM)-based 3-D tumor growth prediction system using longitudinal kidney tumor images. To the best of our knowledge, this is the first kidney tumor growth prediction system. The kidney tissues are classified into three types: renal cortex, renal medulla, and renal pelvis. The reaction-diffusion model is applied as the tumor growth model. Different diffusion properties are considered in the model: the diffusion for renal medulla is considered as anisotropic, while those of renal cortex and renal pelvis are considered as isotropic. The FEM is employed to solve the diffusion model. The model parameters are estimated by the optimization of an objective function of overlap accuracy using a hybrid optimization parallel search package. The proposed method was tested on two longitudinal studies with seven time points on five tumors. The average true positive volume fraction and false positive volume fraction on all tumors is 91.4% and 4.0%, respectively. The experimental results showed the feasibility and efficacy of the proposed method.  相似文献   

14.
Vibroacoustography (VA) is an ultrasound-based modality sensitive to stiffness and free from speckle and possesses some advantages over conventional ultrasound imaging in terms of image quality. The primary objective here is to show its feasibility in detecting/imaging kidney stones (KSs) in vitro . In VA, two intersecting ultrasound beams driven at two different frequencies f (1) and f (2), respectively, are focused within a freshly excised porcine kidney attached to a solid frame with elastic rubber bands, while the amplitude of the acoustic emission pressure field produced at the difference frequency Δf = | f(1) - f(2) | is detected by a low-frequency hydrophone. The received low-frequency signal is bandpass filtered and amplified, then digitized by a 14-bits/sample digitizer. The data are then recorded on a computer and processed numerically to construct the images. 2-D magnitude VA images are obtained at different depths within the kidney before and after stone implantation, showing kidney features and stones shapes. Experiments conducted in a water tank on a chalk sphere as well as a series of excised kidneys in which stones are artificially embedded show that all the implanted stones are detected at all chosen depths, when compared with an X-ray fluoroscopy taken to be the reference image. The resulting VA images, obtained from a nonionizing type of radiation (i.e., ultrasound waves) as compared to fluoroscopy, are speckle free unlike conventional ultrasound images. The results presented in this preliminary feasibility study show that VA allows imaging KSs in vitro, and provide the impetus to further develop and investigate VA imaging in a clinical setting for in vivo applications.  相似文献   

15.
Transplacental effect of cobalamin coenzyme, adenosylcobalamin (Adocbl), on the carcinogenic action of N-nitroso-N-ethylurea (ENU) was studied in culture of the mouse embryonic kidney tissue by histoautoradiography. Coenzyme methylmalonyl-CoA-mutase, Adocbl, injected into DBA/2 mice in the prenatal period did not stimulate the proliferative activity of epithelial cells of the embryonic kidney. The treatment with Adocbl did not intensify hyperplastic changes common for the early stages of carcinogenesis. The frequency of hyperplastic changes mainly of focal proliferation in kidney explants with the combined administration was considerably lower than with the isolated action of the carcinogen and amounted to 8.7% and 21.5%, respectively (P less than 0.001).  相似文献   

16.
17.
Glomerular capillary hemorrhage (GCH) in rat kidney provided a model for assessing in vivo gas body efficacy in diagnostic or therapeutic applications of ultrasound. Two diagnostic ultrasound machines were utilized: one monitored the harmonic B-mode contrast enhancement of the left kidney and the other exposed the right kidney for GCH production. Definity contrast agent was infused at 1, 2, 5, or 10 $mu$L/(kg·min) and infusion durations were 30, 60, 120, or 300 s. Exposure of the right kidney was at a peak rarefactional pressure amplitude of 2.3 MPa at 1.5 MHz. The circulating dose was estimated with a simple model of agent dilution and gas body loss. For 300 s infusion at 5 $mu$L/(kg·min), the left kidney image brightness increased to a plateau with an estimated 6.4 $pm$ 1.3 $mu$L/kg circulating dose with no GCH in histological sections. Exposure of the right kidney with a 1-s image interval reduced the estimated circulating dose to 1.3 $pm$ 0.3 $mu$ L/kg and induced 68.4% GCH. Dose and duration increases gave rapidly diminishing treatment effectiveness per gas body. The effective in vivo agent dose in rats can be reduced greatly due to high gas body destruction in the small animal, complicating predictions for similar conditions of human treatment.   相似文献   

18.
This paper describes the application of a new probabilistic shape and appearance model (PSAM) algorithm to the task of detecting polycystic kidney disease (PKD) in X-ray computed tomography images of laboratory mice. The genetically engineered PKD mouse is a valuable animal model that can be used to develop new treatments for kidney-related problems in humans. PSAM is a statistical-based deformable model that improves upon existing point distribution models for boundary-based object segmentation. This new deformable model algorithm finds the optimal boundary position using an objective function that has several unique characteristics. Most importantly, the objective function includes both global shape and local gray-level characteristics, so optimization occurs with respect to both pieces of information simultaneously. PSAM is employed to segment the mouse kidneys and then texture measurements are applied within kidney boundaries to detect PKD. The challenges associated with the segmentation non-rigid organs along with the availability of a priori information led to the choice of a trainable, deformable model for this application. In 103 kidney images that were analyzed as part of a preclinical animal study, the mouse kidneys and spine were segmented with an average error of 2.4 pixels per boundary point. In all 103 cases, the kidneys were successfully segmented at a level where PKD could be detected using mean-of-local-variance texture measurements within the located boundary.  相似文献   

19.
Targeting the pivotal pathological processes of acute kidney injury (AKI) and parallelly monitoring the treatment process has emerged as an intriguing strategy for the timely tailored treatment of AKI, especially in the acute phase. Unfortunately, current clinical treatment approaches are restricted to supportive care, which shows limited efficiency. Herein, a multiantioxidant-cooperative polydopamine-based nanotheranostic platform (mc-PDATP) is reported to achieve imaging-assisted time-sensitive therapy of AKI. Benefiting from the decoration of atomic Cu, mc-PDATP comprehensively mimics the complicated antioxidant defense system as in natural environment, thus displaying improved catalytic activity to multiple toxic reactive oxygen species (ROS). Consequently, both in vitro and in vivo experiments confirm mc-PDATP can efficiently protect the kidney from ROS attack and rescue the kidney function via targeting the inflammatory network of AKI. In addition, the coordinated atomic Gd contributes to a desired magnetic resonance (MR) T1-weighted contrast effect of mc-PDATP, which can be used to construct the sensitive MR histogram imaging signatures for pinpointing treatment effects in a timely manner. The study represents an innovative strategy for anti-AKI therapy, which will facilitate the development of next-generation theranostic nano-antioxidants.  相似文献   

20.
By means of the reaction of specific inhibition of precipitation in agarose gel and using the rabbit immune sera against nuclear nonhistone proteins (NHP) in the NHP-DNA complexes isolated from the rat kidney it is shown that the single intraperitoneal injection of hepatocarcinogens, 4-dimethylaminoazobenzene (DAB) or N-nitrosodiethylamine (DEN) induces the appearance of hetero-organic antigens of the kidney nature in the NHP pattern of the liver. These antigens identical, as it proved to be, to the same NHP-antigens from the cells of transplantable rat hepatoma 27 and ascitic Zajdela hepatoma could be found in the NHP pattern of the rat liver during 1 to 12 and 1 to 64 days after the DAB and DEN injection, respectively. In all cases when the hetero-organic NHP-antigens were found the profiles of proper phosphoprotein kinase activity of the fractions of NHP eluted by 0.4-0.5 M NaCl using gradient chromatography on phosphocellulose contained peaks that were not characteristic to the liver NHP but were typical of NHP from the intact rat kidney. In the SDS-PAAG electrophoresis the mentioned fractions form one line with the molecular weight 15000-20000.  相似文献   

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