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A case of bilateral hypernephroma treated by right heminephrectomy in situ and "benchwork" excision of two tumors from the left kidney followed by autotransplantation is presented. Follow-up examination has demonstrated good renal function with no evidence of tumor recurrence or metastasis. This case illustrates the feasibility of benchwork operation and its application to renal tumors, particularly when these tumors are bilateral and preservation of renal tissue is imperative. Long-term follow-up of patients managed by this technique is mandatory. 相似文献
23.
Effect of heparin on high glucose induced proliferation and expression of matrix metalloproteinases in normal human mesangial cells 总被引:1,自引:0,他引:1
Zhou Qiao-ling Yasumoto Yuichiro Tsukamoto Masatoshi Nozaki Tsuyoshi Sogabe Atsushi Harada Kouji Zhang Yi-xiang Lin Xiao-yan Zhang Yang-de Arima Terukatsu 《中南工业大学学报(英文版)》2005,12(1):359-364
Background The pathogenesis of diabetic nephropathy (DN) is a complex pathophysiological process. Its precise mechanism is not fully
known. In recent years it has been recognized that synthesis of various extracelluar matrix (ECM) components may increase,
and that degradation of ECM may decrease in DN. It was reported heparin could inhibit mesangial cells proliferation in vitro.
The main aim of this study is to explore whether heparin inhibits proliferation of mesangial cells grown in high glucose concentration
and to measure the effect of heparin on matrix metalloproteinases (MMPs) expression in mesangial cells. Methods The medium contained either low glucose (5 mmol/L) or high glucose (25 mmol/L). The concentrations of heparin in the culture
medium were 0, 25, 50, 100, 200 or 400 μg/mL. A metabolic (WST-1) assay was used to measure mesangial cell proliferation and
Western blot analysis was used to measure MMPs expression of mesangial cells. Results Normal human mesangial cell (NHMC) proliferation was higher in high glucose (HG) medium than in low glucose (LG) medium.
They showed a 1.93 fold expansion after 72 h in high glucose in contrast to a 1.63 fold expansion in low glucose. In the presence
of heparin, mesangial cells proliferation was inhibited, which was more obvious at high glucose concentrations than at low
glucose concentrations. In high glucose, with heparin concentration of 50, 100, 200 and 400 μg/mL, the mesangial cells showed
a 0.61 fold, 0.52 fold, 0.52 fold and 0.41 fold reductions in cell number compared to cells grown without heparin. In low
glucose, only concentrations of 200 μg/mL and 400 μg/mL showed reduction in cell number, namely 0.54 fold and 0.45 fold, when
compared to cells grown without heparin. In Western blot analysis, MMP1, MMP2, MMP3 and MMP9 was expressed by mesangial cells expressed in both high and low glucose concentrations, which was more prominent in high
glucose medium. Incubation of heparin further increased expression of MMP1, MMP2, MMP3 and MMP9. Conclusions This study suggests that glucose can accelerate mesangial cell proliferation while heparin can reduce proliferation, being
more obvious at high glucose concentrations. Higher glucose concentrations led to increased MMP expression, which may take
part in the regulation of mesangial matrix synthesis and degradation. Addition of heparin resulted in a corresponding increase
in MMP expression, most notably at high glucose concentrations, indicating a potentially renoprotective role in DN.
Foundation item: Project (30370663) supported by the National Natural Science Foundation of China 相似文献
24.
In this paper we propose a new algorithm to detect the irises of both eyes from a face image. The algorithm first detects the face region in the image and then extracts intensity valleys from the face region. Next, the algorithm extracts iris candidates from the valleys using the feature template of Lin and Wu (IEEE Trans. Image Process. 8 (6) (1999) 834) and the separability filter of Fukui and Yamaguchi (Trans. IEICE Japan J80-D-II (8) (1997) 2170). Finally, using the costs for pairs of iris candidates proposed in this paper, the algorithm selects a pair of iris candidates corresponding to the irises. The costs are computed by using Hough transform, separability filter and template matching. As the results of the experiments, the iris detection rate of the proposed algorithm was 95.3% for 150 face images of 15 persons without spectacles in the database of University of Bern and 96.8% for 63 images of 21 persons without spectacles in the AR database. 相似文献
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Adhesion between polymer surface modified by graft polymerization and tissue during surgery using an ultrasonically activated scalpel device 下载免费PDF全文
Kwangwoo Nam Takuya Iwata Tsuyoshi Kimura Hiroki Ikake Shigeru Shimizu Toru Masuzawa Akio Kishida 《应用聚合物科学杂志》2014,131(20)
In the field of surgery, achieving adhesion between a polymer implant and tissue poses a challenge considering that suturing is not appropriate for the stability of such implants. An ultrasonically activated scalpel that generates heat by mechanical vibration and promotes adhesion between a polymer implant and native tissue by pressing the two materials together has very good potential for application in the field. To determine the type of polymer that is suitable for the purpose, we investigated polyethylene (PE) and polystyrene (PS) films, the surfaces of which were activated by corona discharge. Graft polymerization was then performed on the corona‐treated surfaces to vary their properties. The corona‐treated PE and PS films grafted with poly(acrylic acid), poly(methacrylic acid), poly(vinyl benzylacrylic acid), and poly(hydroxylethyl acrylate), respectively, adhered to the tissue when the ultrasonically activated scalpel was applied. The heat generated by the mechanical vibration and the applied pressure enabled the carboxyl or hydroxyl groups to bond with the proteins in the extracellular matrix. We therefore concluded that it was possible to integrate this technique in the development of new types of polymer devices that could be stably implanted in a living body. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014 , 131, 40885. 相似文献
28.
Kunihiro Ogata Tokio Umino Tsuyoshi Nakayama Eiichi Ono Toshiaki Tsuji 《Advanced Robotics》2017,31(6):303-310
Development of clothing in consideration of the shape and body function of a person with spinal cord injury is an important task. Then, a dummy robot with a deformation mechanism was developed in this study for evaluating the comfortable level of clothings. Specifically, a trunk joint mechanism and an abdominal mechanism that can realize various deformations of the abdominal area and various trunk poses were developed. The trunk joint mechanism was implemented in order to simulate the seated posture of persons with spinal cord injury. The abdominal deformation mechanism was implemented using linear actuators and rotating servomotors in order to simulate abdominal obesity of persons with spinal cord injury. Further, a tactile sensor system was developed for measuring the clothing pressure on the abdominal area and evaluating the comfort or discomfort of clothing. 相似文献
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Hyun Soon Park Yasukazu Murakami Keiichi Yanagisawa Tsuyoshi Matsuda Ryosuke Kainuma Daisuke Shindo Akira Tonomura 《Advanced functional materials》2012,22(16):3434-3437
Peculiar magnetic domain walls produced in Heusler alloys, which have attracted renewed interest due to their potential application to actuators and spintronic devices, are studied here using electron holography. The observations reveal unexpectedly narrow magnetic domain walls, the width of which showed perfect agreement with that of the antiphase boundaries (APB, e.g., only 3 nm). While the results can be explained by the significant depression of ferromagnetism due to the local chemical disorder, the electron phase shift indicates that ferromagnetic correlation still remains in the APB region. 相似文献