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目的为影像学诊断提供肺叶间裂的变异资料。方法运用64层螺旋进行CT扫描,选择451例肺部无明显病变或手术影响观察肺叶间裂的患者,应用MPR技术显示、观察并统计肺叶间裂及其变异情况。结果451例被检查者中有肺叶间裂变异者占69.18%(312例);其中,右肺变异者占62.53%(282例),左肺变异者占18.18%(82例)。右肺282例中177例存在一种变异,105例合并其它变异。左肺82例中25例存在一种变异,57例均合并其它的变异。肺叶间裂变异存在3种类型:(1)肺叶间裂不全,其中右水平裂不全占45.45%(205例),右斜裂不全占19.51%(88例),左斜裂不全占16.41%(74例);(2)肺叶间裂缺如:其中右水平裂缺如占0.89%(4例),右水平裂合并斜裂缺如占0.22%(1例),左斜裂缺如占0.44%(2例)(;3)附属裂:存在附属裂的占13.97%(63例),其中右肺附属裂占11.97%(54例),左肺附属裂占2.44%(11例)。结论64层螺旋CT扫描结合多平面重组技术能显示肺叶间裂各种变异,可为临床学科提供可靠、有价值的影像学资料。  相似文献   

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目的利用计算机图像处理系统对颅脑主要重要结构进行三维成像,探索建立1套正常颅脑部MRI图像、断层标本及三维重建图像的数据对照计算机模型,为影像诊断及颅脑部手术定位提供形态依据。方法利用Microsoft Visual Studio将获得的MRI图像、断层标本图像及重建的三维图像建立数据模型。结果建立的数据模型提供了颅脑部正常解剖学影像学对比特点,构建了主要结构的三维立体模型图像,使抽象结构数字化、立体化、可视化,有助于对人脑的理解。结论本数据模型把颅脑结构的三维图像结合到标本MRI的对比图中,有利于初次接触颅脑断层的初学者。  相似文献   

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Our group is developing an artificial lung as a bridge to transplant. We evaluated the sheep pulmonary artery (PA) for the presence or absence of a septum, which may increase PA resistance and affect artificial lung flow. We also measured the PA size to determine whether it is a suitable conduit for artificial lung implantation using a PA-PA shunt. Adult Suffolk ewes in two groups were studied. Group 1 consisted of animals (n = 12, 30-43 kg) prepared for thoracotomy. Group 2 (n = 21, 30-43 kg) consisted of postmortem dissections. In both groups, the length and girth of the PA was measured. The heart and lungs were removed on all postmortem animals (group 2), the ductus arteriosum was crosscut, and the common PA was incised. The average length of the PA in live animals was 5.5 cm and the average diameter was 2.2 cm. The average length of the PA in postmortem animals was 4.8 cm and the average diameter was 2.0 cm. All pulmonary arteries were aseptate, and the ligamentum arteriosum in each PA was not patent. We conclude that the PA is not a source of increased resistance and is a suitable conduit for artificial lung implantation in the PA-PA configuration.  相似文献   

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肺动脉修复与重建的应用解剖学   总被引:1,自引:0,他引:1  
目的 :为肺动脉修复与重建提供解剖学基础。方法 :对 3 0例成人尸体肺动脉心包外段的长度、外径、分支及奇静脉各段的长度、外径进行观测。结果 :左、右肺动脉出心包返折处的外径分别为 (13 .8±2 .6)mm ,(15 .3± 2 .8)mm ;发出下叶上支处的外径分别为 (8.4± 2 .1)mm ,(9.1± 2 .3 )mm。左、右肺动脉出心包处至下叶上支动脉起点处长度分别为 (4 .9± 0 .6)cm ,(3 .8± 0 .8)cm。奇静脉第 2段、第 3段 (奇静脉弓 )的长度分别为 (4 .2± 0 .9)cm ,(3 .1± 0 .6)cm。结论 :(1)如肿瘤侵犯肺动脉主干及其分支根部 ,动脉切除后可采用袖式吻合及侧壁扩大成形术 ;(2 )如右肺动脉侧壁切除缺损较大时 ,首选自体奇静脉片进行重建。  相似文献   

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For quantitative image reconstruction in positron emission tomography attenuation correction is mandatory. In case that no data are available for the calculation of the attenuation correction factors one can try to determine them from the emission data alone. However, it is not clear if the information content is sufficient to yield an adequate attenuation correction together with a satisfactory activity distribution. Therefore, we determined the log likelihood distribution for a thorax phantom depending on the choice of attenuation and activity pixel values to measure the crosstalk between both. In addition an iterative image reconstruction (one-dimensional Newton-type algorithm with a maximum likelihood estimator), which simultaneously reconstructs the images of the activity distribution and the attenuation coefficients is used to demonstrate the problems and possibilities of such a reconstruction. As result we show that for a change of the log likelihood in the range of statistical noise, the associated change in the activity value of a structure is between 6% and 263%. In addition, we show that it is not possible to choose the best maximum on the basis of the log likelihood when a regularization is used, because the coupling between different structures mediated by the (smoothing) regularization prevents an adequate solution due to crosstalk. We conclude that taking into account the attenuation information in the emission data improves the performance of image reconstruction with respect to the bias of the activities, however, the reconstruction still is not quantitative.  相似文献   

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We have produced an optically clear, close to water-equivalent gel that is radio-fluorogenic, i.e. fluoresces in UV light after exposure to high-energy radiation. Its potential as a 2D and 3D dosimetric medium is demonstrated by fixed fluorescent images of the cross-section, track and intersection of collimated (10 × 10 or 5 × 5 mm(2)) 205 kVp x-ray beams. The images, produced by doses on the order of 10 Gy, are formed instantaneously and can be digitally recorded and scanned with a spatial resolution on the order of 0.1 mm. No loss of spatial resolution occurs on standing under ambient conditions for at least 3 days.  相似文献   

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We present a technique that accurately reconstructs complex three dimensional blood vessel geometry from 2D intravascular ultrasound (IVUS) images. Biplane x-ray fluoroscopy is used to imagethe ultrasound catheter tip at a few key points along its path as the catheter is pulled through the blood vessel. An interpolating spline describes the continuous catheterpath. The IVUS images are located orthogonal to the path, resulting in a non-uniform structured scalar volume of echo densities. Isocontour surfaces are used to view the vessel geometry, while transparency and clipping enable interactive exploration of interior structures. The two geometries studied are a bovine artery vascular graft having U-shapeand a constriction, and a canine carotid artery having multiple branches and a constriction. Accuracy of the reconstructions is established by comparing the reconstructions to (1) silicone moulds of the vessel interior, (2) biplane x-ray images, and (3) the original echo images. Excellent shape and geometry correspondence was observed in both geometries. Quantitative measurements made at key locations of the 3D reconstructions also were in good agreement with those made in silicone moulds. The proposed technique is easily adoptable in clinical practice, since it uses x-rays with minimal exposure and existing IVUS technology.  相似文献   

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We present a technique that accurately reconstructs complex three dimensional blood vessel geometry from 2D intravascular ultrasound (IVUS) images. Biplane x-ray fluoroscopy is used to image the ultrasound catheter tip at a few key points along its path as the catheter is pulled through the blood vessel. An interpolating spline describes the continuous catheter path. The IVUS images are located orthogonal to the path, resulting in a non-uniform structured scalar volume of echo densities. Isocontour surfaces are used to view the vessel geometry, while transparency and clipping enable interactive exploration of interior structures. The two geometries studied are a bovine artery vascular graft having U-shape and a constriction, and a canine carotid artery having multiple branches and a constriction. Accuracy of the reconstructions is established by comparing the reconstructions to (1) silicone moulds of the vessel interior, (2) biplane x-ray images, and (3) the original echo images. Excellent shape and geometry correspondence was observed in both geometries. Quantitative measurements made at key locations of the 3D reconstructions also were in good agreement with those made in silicone moulds. The proposed technique is easily adoptable in clinical practice, since it uses x-rays with minimal exposure and existing IVUS technology.  相似文献   

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Treatment planning for patients undergoing radiation therapy is often performed based on four-dimensional computed tomography (4DCT) when respiratory motion is present, as in lung cancer patients. 4DCT is used to define the internal target volume (ITV) that, ideally, incorporates all potential locations of the tumour. In this work, we use the locations of gold fiducial markers implanted in lung tumours of eight patients to represent tumour motion. These fiducial locations are used in a simulation of a four-slice CT scanner to generate the ITV for 10, 20 and 30 mm diameter model tumours. To demonstrate instabilities in the ITV definition based on 4DCT, the ITV calculation was repeated for the same patients for consecutive scan start times, staggered by 1 s. The volumetric difference in the ITV and the per cent of time that the ITV contains in the tumour are both evaluated. The ITV from a single patient was found to vary by 46%-127% for a tumour diameter of 10 mm. The ITV did not cover the entirety of the tumour 11%-74% of the time for a 10 mm tumour diameter.  相似文献   

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Summary In this study on the development of the pulmonary acinus in fetal rat lung use was made of an antiserum, rabbit anti-mouse, that recognizes the type II alveolar epithelial cell or its precursor (a cuboidal cell lacking multilamellar bodies) by the presence of a cell-specific antigen. This serum had already been used in studies on mouse-lung development in our laboratory.Immunoblotting experiments showed that this serum reacts with surfactant-associated proteins in the pellet fraction of rat-lung lavage fluid having molecular weights of about 26,000, 32,000, and 38,000 daltons. In adult and fetal rat-lung homogenates the antiserum reacts with proteins with apparent molecular weights of about 40,000 and 42,000 daltons, probably also surfactant-associated proteins. No reaction with serum proteins was seen.Use of this antiserum in immuno-incubations of frozen sections of lungs of 15- to 21-day-old rat embryos showed that the type II epithelial cell or its precursor first appears on day 16 in embryos weighing 349–398 mg. Our results indicate that in the rat — as in the mouse — the bronchial and respiratory portions develop from morphologically and immunologically different parts of the tubular system in the fetal lung. The basic structure in the genesis of the pulmonary acinus is a tubule, called the acinar tubule, which is lined by the type II epithelial cell or its precursor.Supported by a grant from the Netherlands Asthma Foundation  相似文献   

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The structures of superior mediastinum and their spatial relationships are complex and difficult to master. This study aimed to compare visualization of the superior mediastinum based on computed tomography (CT) images and on the thin sections of the Chinese visible human (CVH) data set to provide a sectional anatomical basis for diagnostic imaging of superior mediastinal pathology. CVH sections of the mediastinum of a 35‐year old male were compared with plain and enhanced CT images of a 45‐year old male without apparent abnormalities in the upper chest. In addition, a three‐dimensional model based on the CVH sections was compared with a model based on CT images. Although CT imaging is noninvasive and can be carried out in many individuals, its weakness is clearly the visualization of small soft tissue structures. In this respect, the sectional anatomical approach of the CVH images is complementary, as it visualizes these small soft tissue structures due to the higher resolution in the plain of sectioning and the color of the different structures in the section. Three‐dimensional surface and volume rendering of reconstructions of the CVH data set can help medical students and less experienced thoracic surgeons to familiarize themselves with the topographic anatomy of the superior mediastinal structures and their spatial relationships, and thus with interpreting CT images of patients. Clin. Anat. 25:1051–1061, 2012. © 2012 Wiley Periodicals, Inc.  相似文献   

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For measurement value logging of board angle values during balance training, it is necessary to develop a measurement system. This study will provide data for a balance study using the smartcard. The data acquisition comes automatically. An individually training plan for each proband is necessary. To store the proband identification a smartcard with an I2C data bus protocol and an E2PROM memory system is used. For reading the smartcard data a smartcard reader is connected via universal serial bus (USB) to a notebook. The data acquisition and smartcard read programme is designed with Microsoft® Visual C#. A training plan file contains the individual training plan for each proband. The data of the test persons are saved in a proband directory. Each event is automatically saved as a log-file for the exact documentation. This system makes study development easy and time-saving.  相似文献   

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In adult high-frequency oscillatory ventilation (HFOV) with an R100 artificial ventilator, exhaled gas from patient's lung may warm the temperature probe and thereby disturb the humidification of base flow (BF) gas. We measured the humidity of BF gas during HFOV with frequencies of 6, 8 and 10 Hz, maximum stroke volumes (SV) of 285, 205, and 160 ml at the respective frequencies, and, BFs of 20, 30, 40 l/min using an original lung model. The R100 device was equipped with a heated humidifier, Hummax Ⅱ, consisting of a porous hollow fiber in circuit. A 50-cm length of circuit was added between temperature probe (located at 50 cm proximal from Y-piece) and the hollow fiber. The lung model was made of a plastic container and a circuit equipped with another Hummax Ⅱ. The lung model temperature was controlled at 37℃. The Hummax Ⅱ of the R100 was inactivated in study-1 and was set at 35℃ or 37℃ in study-2. The humidity was measured at the distal end of the added circuit in study-1 and at the proximal end in study-2. In study-1, humidity was detected at 6 Hz (SV 285 ml) and BF 20 l/min, indicating the direct reach of the exhaled gas from the lung model to the temperature probe. In study-2 the absolute humidity of the BF gas decreased by increasing SV and by increasing BF and it was low with setting of 35℃. In this study setting, increasing the SV induced significant reduction of humidification of the BF gas during HFOV with R100.  相似文献   

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BACKGROUND: There is conflicting evidence regarding levels of leptin in depression. In this study we aimed to investigate the relationship between serum leptin level and depression in a community sample of women using both cross-sectional and longitudinal data. METHODS: From among 510 women aged 20-78 yr, 83 were identified with a lifetime history of major depressive disorder or dysthymia, ascertained using the Structured Clinical Interview for DSM-IV-TR Research Version, Non-patient edition (SCID-I/NP). Serum leptin levels were measured by radioimmunoassay. Medication use and lifestyle were self-reported and body mass index (BMI) determined from measures of height and weight. RESULTS: Using multiple linear regression, serum leptin levels were greater among women with a lifetime history of depression compared to women without any history of depression, independent of BMI. Adjusted geometric mean values of serum leptin were 16.37 (95%CI 14.70-18.23) ng/mL for depressed and 14.46 (95%CI 13.79-15.16) ng/mL for non-depressed women (P=0.039). The hazard ratio (HR) for a de novo depressive disorder over five years increased 2.56-fold for each standard deviation increase in log-transformed serum leptin among non-smokers and this was not explained by differences in BMI, medications or other lifestyle factors (HR=2.56, 95%CI 1.52-4.30). No association was observed for smokers. LIMITATIONS: There is potential for unrecognised confounding, recall bias and transient changes in body composition. CONCLUSION: Women with a lifetime history of depression have elevated levels of serum leptin, and elevated serum leptin predicts subsequent development of a depressive disorder.  相似文献   

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The alveolar macrophage plays an important role in the lung's defense against inhaled particles, but few studies have addressed the motile behavior of these cells. In this study, we measured alveolar macrophage random motility using a modification of the under-agarose assay. The cells were exposed to a uniform concentration of F-norleucyl-leucyl-phenylalanine (FNLLP) in an agarose system, establishing conditions for stimulated random motility (or chemokinesis). Experimental results were compared with a theoretical model of cell migration. In this model, chemokinesis was expressed as a random motility coefficient, mu, which is the cellular equivalent of a diffusion coefficient for a molecule. The experimental data that described the migration of alveolar macrophages (density profiles) agreed well with the theoretical model. The random motility coefficient ranged from 1 X 10(-9) cm2/sec (no FNLLP) to a maximum of 1 X 10(-8) cm2/sec at 10(-9) M FNLLP. For concentrations of FNLLP greater than 10(-9) M, the random motility decreased to a constant value of 3 X 10(-9) cm2/sec. The maximum random motility response was observed at an FNLLP concentration one order of magnitude below the measured FNLLP equilibrium dissociation constant, Kd, of 6 X 10(-8) M for alveolar macrophages and was essentially constant over a large range of FNLLP concentrations on either side of the Kd value. These results suggest that such a combined experimental and theoretical approach reduces the limitation of previous techniques that depended largely on physical characteristics of the assay and more closely identifies and measures intrinsic properties of cell motility.  相似文献   

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Several techniques for diagnosing adenocarcinoma of the lung are commonly available, but the frequency of their use and diagnostic sensitivity may vary. Twenty cases of primary lung adenocarcinoma obtained at surgery were studied by the following four routine techniques: light microscopy (LM) using hematoxylin-eosin (H&E) stain, mucicarmine stain, and PAS-diastase stain, and electron microscopy (EM). Three observers independently determined the positivity (0 [none], +/- [equivocal], 1 + [slight], 2 + [moderate], 3 + [marked]) of each of these cases for lumen formation in H&E-stained sections (LM lumens), intracytoplasmic (cytoplasmic mucicarmine) or intraluminal (luminal mucicarmine) mucicarmine, intracytoplasmic (cytoplasmic PAS) or intraluminal (luminal PAS) PAS-diastase, and lumen formation (EM lumens) or microvilli (EM microvilli) on electron microscopy. Comparative matching of these seven microscopic determinants (using Wilcoxon signed-rank test) demonstrated significant (P less than .01) sensitivity of EM microvilli over EM lumens, EM microvilli over luminal mucicarmine, cytoplasmic PAS over luminal mucicarmine, EM microvilli over cytoplasmic mucicarmine, cytoplasmic PAS over cytoplasmic mucicarmine, and EM microvilli over LM lumens, and a significant (P less than .05) sensitivity of cytoplasmic PAS over LM lumens, EM microvilli over luminal PAS, luminal PAS over luminal mucicarmine, and cytoplasmic PAS over EM lumens. Friedman's nonparametric test (P less than .05) indicated a significant difference among the microscopic determinants. The most sensitive was EM microvilli (mean rank score, 5.17) followed by cytoplasmic PAS (4.77), luminal PAS (4.02), cytoplasmic mucicarmine (3.62), LM lumens (3.52), EM lumens (3.47), and luminal mucicarmine (3.40). However, each of the diagnostic techniques had case examples positive for one, but not for the others, indicating that maximum yield of adenocarcinoma diagnoses will be obtained by performing all four techniques (H&E, mucicarmine, PAS-diastase, and electron microscopy.  相似文献   

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