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21.
目的探讨大鼠脂肪来源间充质干细胞(MSC)对大鼠肝移植术后急性排斥反应的作用。方法分离、培养SD大鼠MSC,体外混合淋巴细胞培养(MLC)体系中,研究MSC对Wistar大鼠T细胞增殖的抑制作用。以SD与Wistar大鼠为供受体建立肝移植模型。随机分为MSC处理组与空白对照组,术后第7天检测肝功能、血清白细胞介素(IL)-2和白细胞介素(IL)-10水平、肝组织病理形态及肝细胞凋亡。结果体外MLC中,Wistar大鼠T细胞增殖明显受抑,抑制率为48.44%。实验组血清丙氨酸转氨酶(ALT)、天冬氨酸转氨酶(AST)、总胆红素(TBIL)、IL-2、IL-10分别为(134.2±45.0)、(162.5±30.5)U/L、(30.6±5.4)μmol/L、(187.35±18.26)、(193.95±37.62)μg/L;对照组上述指标分别为(355.6±54.3)、(296.4±71.2)U/L、(145.7±28.6)μmoL/L、(295.73±57.15)、(75.12±11.23)μg/L,两组差异有统计学意义(P<0.05);病检提示实验组排斥反应较对照组明显减轻;脱氧脲核苷酸缺口末端标记(TUNEL)检测提示实验组肝细胞凋亡程度明显低于对照组(P<0.05)。结论供体来源MSC能明显抑制MLC体系中受体源T细胞的增殖,并能显著减轻大鼠肝移植术后急性排斥反应。 相似文献
22.
足底深支或(和)第一跖背动脉逆行足背岛状皮瓣的临床应用 总被引:4,自引:0,他引:4
目的探索足部远端软组织缺损修复的较佳方法。方法采用足底深支或(和)第1跖背动脉逆行足背岛状皮瓣对6例足部远端软组织缺损创面进行修复。结果6例患者均一次性修复,软组织缺损最大面积8cm×6cm,术后随访1~4年,足部功能与外观均较满意。结论足底深支或(和)第1跖背动脉逆行足背岛状皮瓣血管解剖比较恒定,操作简单,是修复足远端软组织缺损的较好方法。 相似文献
23.
目的探讨睾丸鞘膜瓣覆盖技术在尿道畸形和尿道瘘修复中的效果。方法2002年起对38例尿道下裂手术和术后尿道瘘,采用睾丸鞘膜下组织蒂鞘膜瓣覆盖修复。结果术后随访半年至1年,除1例尿道上裂术后瘘修复后再次发生尿道瘘外,其余均获成功,未再出现尿道瘘或尿道狭窄,阴茎外观满意,勃起正常。结论采用该方法可有效防止尿瘘再发生,提高手术成功率且易于获取,对睾丸无不良影响。 相似文献
24.
目的:探求上唇外侧组织瓣在修复较大面积下唇缺损中的作用。方法:根据患者下唇缺损情况,设计上唇外侧组织瓣,旋转后插入缺损组织,同时在缺损吻合处,将上层外侧旋转瓣内侧粘膜肌肉向外牵拉形成部分新的红唇,然后逐层相对缝合,修复缺损。结果:自2003年1月应用此方法修复患者6例,术后随访1~2年,唇部外形好,无流涎,无口闭合不全,效果满意。 相似文献
25.
Nishida Koyo Mihara Kiyoshi Takino Toichi Nakane Sachi Takakura Yoshinobu Hashida Mitsuru Sezaki Hitoshi 《Pharmaceutical research》1991,8(4):437-444
The effect of electric charge on the hepatic disposition of macromolecules was studied in the rat. Charged derivatives of dextran (T-70) and bovine serum albumin (BSA), mitomycin C–dextran conjugates (MMC-D), and lactosaminated BSA (Lac-BSA) were employed as model macromolecules. After intravenous injection, cationic macromolecules were rapidly eliminated from plasma because of their extensive hepatic uptake, while anionic and neutral macromolecules were slowly eliminated. Cationic macromolecules were recovered from parenchymal and nonparenchymal hepatic cells at a cellular uptake (per unit cell number) ratio of 1.4–3.2, while that of Lac-BSA was 14. During liver perfusion using a single-pass constant infusion mode, cationic macromolecules were continuously extracted by the liver, with extraction ratios at steady-state (E
ss) ranging between 0.03 and 0.54, whereas anionic and neutral macromolecules were almost completely recovered in the outflow at steady state. The E
ss for cationized BSA (Cat-BSA) and cationic MMC-Dcat were concentration dependent and decreased at low temperatures and in the presence of colchicine and cytochalasin B. The possible participation of the internalization process in the uptake of cationic macromolecules by hepatocytes was suggested. 相似文献
26.
目的:探讨头皮电烧伤骨外露用头皮扩张皮瓣移植修复的临床效果。方法:采用早期扩创,保留部分坏死骨质,用邻近头皮扩张使带毛发的头皮面积扩大后移植覆盖创面,电性失活骨质在血循环良好的皮瓣覆盖下,为周边及基底健康骨质生长起到支架作用,皮瓣扩张到一定面积后移植到裸露骨质上,使其得以修复。结果:在治疗的9例中,除1例皮瓣边缘在1.5cm×1.5cm坏死外,其余皮瓣全部成活,未发生感染坏死,创面均一次性封闭。结论:头皮电烧伤骨外露扩张后皮瓣带毛发修复,可缩短创面愈合时间,外形较好,易掌握,效果较为满意。 相似文献
27.
Angelo Lipira David Limbrick Bruce Haughey Phillip Custer Michael R. Chicoine 《Skull base》2009,19(4):303-309
28.
Javairiah Fatima Scott G. Houghton Michael G. Sarr 《Journal of gastrointestinal surgery》2007,11(8):1052-1056
Small bowel transplantation (SBT) is associated with poorly understood enteric dysfunction. The study of SBT in mice is hindered
by the technical difficulty of orthotopic SBT in the mouse. Our aim was to develop an easy preparation of extrinsic denervation
of the entire jejunoileum in mice as a model of orthotopic SBT. All neurolymphatic tissues accompanying the superior mesenteric
artery (SMA) and vein (SMV) were ligated just distal to the middle colic vessels. The SMA and SMV were then stripped of investing
adventitia, and the mesentery to jejunum and colon were transected radially. Jejunum and colon were not transected and reanastomosed.
To confirm extrinsic denervation 1, 3, and 6 months later, segments of small bowel were stained for protein gene product 9.5
(PGP9.5) and tyrosine hydroxylase (TH). Tyrosine hydroxylase immunoreactive intensity was then quantified using a semiquantitative
analysis. Immunohistochemical fluorescence showed persistence of PGP9.5 immunoreactivity confirming enteric nerves in jejunoileum;
however, there was no TH immunoreactivity in jejunoileum in denervated mice despite the expected preservation of TH immunoreactivity
in the still-innervated duodenum at 1 month. At 3 months, sparse immunoreactivity for TH was present, and by 6 months, reinnervation
of TH-containing nerves appeared similar to controls. Quantification of intensity at each time-point further confirmed this
trend. This technique in the mouse accomplishes a complete extrinsic denervation of jejunoileum early postoperatively (1 and
3 months); reinnervation occurs by 6 months. This is an easily learned murine model of orthotopic SBT.
Presented at the American Gastroenterological Association during Digestive Disease Week in Los Angeles, CA, as a poster presentation
on May 23 2006. Abstract published in GastroenterologyE 2006; 130:A604. 相似文献
29.
Background The incidence rate of incisional hernias after open surgery has been reported to be higher than that of port site hernias
after laparoscopic surgery. No studies have compared the costs for the health care system in treating those two types of hernia.
Methods A systematic review was conducted to obtain the baseline data, and a decision analysis model was created to simulate the occurrence
and recurrence of incisional and port site hernias.
Results The overall risk of having incisional hernias was eight-times higher than that of having port site hernias (7.4% vs 0.9%).
A cost savings of £93 per patient can be generated for the health care system in the UK. Similar results were obtained for
Germany, Italy and France.
Conclusions The additional treatment costs for incisional hernia should be taken into account when the costs of a surgery performed by
open approach are compared with by laparoscopy. 相似文献
30.
E. Drakaki E. Borisova M. Makropoulou L. Avramov A. A. Serafetinides I. Angelov 《Skin research and technology》2007,13(4):350-359
BACKGROUND/PURPOSE: Laser-induced autofluorescence spectroscopy provides excellent possibilities for medical diagnostics of different tissue pathologies including cancer. However, to create the whole picture of pathological changes, investigators collect spectral information from patients in vivo or they study different tumor models to obtain objective information for fluorescent properties of every kind of healthy and diseased tissue. Therefore, it is very important to find the most appropriate, and close to the human skin, animal samples from the fluorescence point of view, which will allow the extrapolation of the animal data to human spectroscopic diagnostics. METHODS: In the present work, we examined the autofluorescence properties of different animal skin tissues, which are considered as the most common skin models. A nitrogen laser was used as an excitation source. Samples of healthy mouse, chicken and pig skin in vivo and/or ex vivo were studied and were compared with results obtained from investigations of healthy human skin in vivo. RESULTS AND CONCLUSION: Specific features of the recorded spectra are discussed and the possible origin of the obtained fluorescence signals is proposed. Quantitative evaluation of data extrapolation for each skin type is also depicted. 相似文献