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111.
112.
Ultrasonographic imaging of abdominal organs and structures of connective tissue as well as the surrounding muscles enables spatial real-time imaging of organ mobility and the mobility of the anatomical environment by justifiable technical expenditure and without X-rays, especially in relation to breathing and the structure and contractile state of abdominal muscles. Furthermore it allows observation of peristalsis and the filling state of hollow organs. The visualization of topographic relationships and the variation during breathing, as well as before, after and somewhat limited during therapy, has become practically possible and is markedly simplified in comparison to X-ray, computed tomography and magnetic resonance examinations. The methodology of examination is principally the same as conventional ultrasonography although the interpretation focuses on some criteria not usually used in conventional ultrasonographic diagnostics. Because of the permanent mobility of organs, muscles and connective tissue during breathing, peristalsis, body movements and changes of body position, the online version of this paper also contains some essential video clips. These provide a more precise impression of the variability of anatomical structures. 相似文献
113.
F. Staub C. Tournoux-Facon J. Roumy C. Chaigneau M. Morichaut-Beauchant P. Levillain C. Prevost C. Aubé J. Lebigot F. Oberti J. B. Galtier H. Laumonier H. Trillaud P. H. Bernard J. F. Blanc S. Sironneau F. Machet J. Drouillard V. de Ledinghen P. Couzigou P. Foucher L. Castéra F. Tranquard Y. Bacq L. d’Altéroche P. Ingrand J. P. Tasu 《European radiology》2009,19(8):1991-1997
We prospectively assessed contrast-enhanced sonography for evaluating the degree of liver fibrosis as diagnosed via biopsy
in 99 patients. The transit time of microbubbles between the portal and hepatic veins was calculated from the difference between
the arrival time of the microbubbles in each vein. Liver biopsy was obtained for each patient within 6 months of the contrast-enhanced
sonography. Histological fibrosis was categorized into two classes: (1) no or moderate fibrosis (F0, F1, and F2 according
to the METAVIR staging) or (2) severe fibrosis (F3 and F4). At a cutoff of 13 s for the transit time, the diagnosis of severe
fibrosis was made with a specificity of 78.57%, a sensitivity of 78.95%, a positive predictive value of 78.33%, a negative
predictive value of 83.33%, and a performance accuracy of 78.79%. Therefore, contrast-enhanced ultrasound can help with differentiation
between moderate and severe fibrosis.
An erratum to this article can be found at 相似文献
114.
Lina Panayiota Aristoteli BSc Mark DP Willcox PhD 《Clinical & experimental ophthalmology》2001,29(3):143-146
The purpose of this study was to compare the adhesion of Pseudomonas aeruginosa ocular isolates to mucin. An adhesion assay was developed using biotin‐labelled P. aeruginosa strains (two corneal ulcer, two acute red eye, one asymptomatic and one standard strains) incubated with porcine gastric mucin immobilized on a nitrocellulose membrane. The adhesion was semiquantified using densitometry. The results showed that all P. aeruginosa strains tested were able to adhere to mucin to various extents with three strains (one corneal ulcer, one acute red eye, one asymptomatic) binding significantly greater than the negative control (P < 0.1). Results suggest that ocular strains of P. aeruginosa strains differ in their adhesion to mucin but this did not correlate with the pathogenic origin of the strain. It is concluded that the adhesion of P. aeruginosa strains to mucin alone may not be a principal determinant of pathogenesis but may be a contributing factor along with other bacterial virulence traits. 相似文献
115.
Moore AD; Godwin JD; Muller NL; Naidich DP; Hammar SP; Buschman DL; Takasugi JE; de Carvalho CR 《Radiology》1989,172(1):249-254
The authors retrospectively evaluated radiographs, computed tomographic (CT) scans, and results of pulmonary function tests (when available) for 17 patients with biopsy-proved pulmonary histiocytosis X. In 11 patients, high-resolution CT was used. In 12 patients, CT demonstrated cystic air spaces, usually less than 10 mm in diameter. In three of these 12, cysts were the only abnormality, but in six others, nodules (usually less than 5 mm in diameter) were also present. Two patients had only nodules and one, only emphysema. CT showed that many lesions that appeared reticular on plain radiographs were actually cysts. CT showed no central or peripheral concentration of lesions, but it did reveal that many small nodules were distributed in the centers of secondary lobules around small airways. CT findings correlated better with the diffusing capacity (rho = -0.71) than did the plain radiographic findings (rho = -0.57). Thus, CT was better than radiography at showing the morphology and distribution of lung abnormalities. 相似文献
116.
Ancient DNA, Strontium isotopes, and osteological analyses shed light on social and kinship organization of the Later Stone Age 总被引:4,自引:0,他引:4
Wolfgang Haak Guido Brandt Hylke N. de Jong Christian Meyer Robert Ganslmeier Volker Heyd Chris Hawkesworth Alistair W. G. Pike Harald Meller Kurt W. Alt 《Proceedings of the National Academy of Sciences of the United States of America》2008,105(47):18226-18231
In 2005 four outstanding multiple burials were discovered near Eulau, Germany. The 4,600-year-old graves contained groups of adults and children buried facing each other. Skeletal and artifactual evidence and the simultaneous interment of the individuals suggest the supposed families fell victim to a violent event. In a multidisciplinary approach, archaeological, anthropological, geochemical (radiogenic isotopes), and molecular genetic (ancient DNA) methods were applied to these unique burials. Using autosomal, mitochondrial, and Y-chromosomal markers, we identified genetic kinship among the individuals. A direct child-parent relationship was detected in one burial, providing the oldest molecular genetic evidence of a nuclear family. Strontium isotope analyses point to different origins for males and children versus females. By this approach, we gain insight into a Late Stone Age society, which appears to have been exogamous and patrilocal, and in which genetic kinship seems to be a focal point of social organization. 相似文献
117.
Technical aids for dermabrasion 总被引:1,自引:0,他引:1
T H Alt 《The Journal of dermatologic surgery and oncology》1987,13(6):638-648
Since the introduction in the 1940s of an effective method for facial dermabrasion using the wire brush, there have been many ancillary procedures developed. Preoperative aids include scar elevation and punch grafting of deep scars prior to dermabrasion. Retinoic acid can prime the skin for more rapid healing. Gas sterilization of electrical equipment eliminates cross-contamination between patients. Intraoperative improvements include regional block anesthesia of the face, staged narcotic administration and newer methods of facial prechilling, and criteria for the ambient air in the operatory. Gentian Violet staining of the face and use of microfoam tape to delineate the mandibular boundary of a dermabrasion are helpful. The use of a custom handle for the spray refrigerant, the safety of Turkish towels used for retraction, and the application of a sharp Buck's curette make the procedure simpler and more effective. Postoperative aids include the use of systemic steroids and the new biological dressings which simplify the postoperative recovery period. 相似文献
118.
Background: Surgical wounds in diabetic patients still remain a problem till the present day. As a common plant found around the world, Hypericum perforatum L. (Hypericaceae) is traditionally prepared as an oily extract and used as a folk remedy for various diseases such as wounds, burns, cuts, etc. This study aims to evaluate the effect of St. John's wort (Hypericum perforatum) on problematic wounds while comparing oral and topical applications. Methods: Incisional and excisional wound models were made on the dorsal regions of 54 diabetic Spraque–Dawley rats. The rats were divided into the following six groups (n = 9): Group 1: control, Group 2: diabetic, Group 3: diabetic oral Hypericum perforatum, Group 4: diabetic topical Hypericum perforatum, Group 5: diabetic oral olive oil, and Group 6: diabetic topical olive oil. Results: Groups 3 and 4 had significantly higher tensile strength, tissue hydroxyproline concentration, and collagen density compared with Group 2. Inflammatory cell density and collagen density on day 3 were significantly higher in Groups 3 and 6 compared with Group 2. On day 21, Groups 3 and 6 had significantly higher fibroblastic activity compared with Group 2. Conclusions: This study has proved that oral St. John's wort has more positive effects on problematic wounds compared with topical St. John's wort and olive oil, which is a vehicle. Hypericum perforatum results with faster inflammatory response and better healing. These results could be an addition to literature about the clinical usage of Hypericum perforatum on diabetic wounds. 相似文献
119.
不同孔径纳米羟基磷灰石人工骨修复兔桡骨缺损效果比较 总被引:4,自引:7,他引:4
目的:纳米级的羟基磷灰石材料与人体内组织成分更为相似,具有更佳的生物性能。评价不同孔径的多孔纳米羟基磷灰石人工骨的骨缺损修复能力,从而筛选出适合的孔径以达到骨传导功能与生物力学性能的良好统一。方法:实验于2005-10/2006-10在深圳市第二人民医院中心实验室完成。①实验材料:纳米羟基磷灰石人工骨以硝酸钙和磷酸二氢铵为原料,采用溶胶-絮凝法制备粉体,运用压力成型、木模成型和浸渍成型分别制得孔隙分布均匀的孔径分别为50~150μm、100~250μm和300~500μm的多孔纳米羟基磷灰石人工骨。②实验动物:雄性新西兰大白兔60只随机分为植入50~150μm孔径材料组、植入100~250μm孔径材料组、植入300~500μm孔径材料组、空白对照组,每组15只。实验过程中对动物处置符合动物伦理学要求。③实验方法:制备双侧桡骨骨缺损动物模型,然后用3种不同孔径的纳米羟基磷灰石人工骨材料植入骨缺损处进行修复,空白对照组不植入任何材料。④实验评估:术后4,8和12周分别行大体标本观察、X射线片观察、扫描电镜观察及生物力学测试,比较各组材料修复骨缺损的能力。结果:实验动物均进入结果分析。①X射线片检查结果:术后4周、8周、12周,植入100~250μm孔径材料组X射线评分高于植入50~150μm,300~500μm孔径材料组,差异有显著性意义(P<0.05)。②生物力学检测结果:术后4周、8周、12周,植入100~250μm孔径材料组生物力学强度高于植入50~150μm,300~500μm孔径材料组,差异有显著性意义(P<0.05)。③扫描电镜观察结果:植入100~250μm孔径材料组成骨效果明显优于植入50~150μm,300~500μm孔径材料组和空白对照组。结论:纳米羟基磷灰石人工骨具有良好的成骨能力,但其骨修复能力受孔径因素的影响,孔径100~250μm的纳米羟基磷灰石人工骨材料成骨能力较好。 相似文献
120.