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101.
102.
目的研究腹内压升高对大鼠中心静脉压和门静脉压的影响。方法将20只成年雄性SD大鼠分别通过颈静脉插管、穿刺门静脉主干法来测定中心静脉压和门静脉压,运用氮气气腹法制作大鼠腹内高压动物模型。建立气腹后分别在0、5、10、15、20、25、30、35、40、45mmHg压力值下测得中心静脉压和门静脉压。结果中心静脉压和腹内压之间的直线回归方程为Y=2.824+0.045X,相关系数r=0.984(P〈0.01);门静脉压和腹内压之间的直线回归方程为Y=8.887+0.939X,相关系数r=0.998(P〈0.01)。结论腹内压与中心静脉压和门静脉压有很好的相关性,可以根据腹内压监测中心静脉压和门静脉压的变化。 相似文献
103.
M. C. van den Heuvel K. P. de Jong M. Boot M. J. H. Slooff S. Poppema A. S. H. Gouw 《American journal of transplantation》2006,6(11):2660-2671
The finer branches of the biliary tree (FBBT) contain a regenerative compartment. We hypothesized that preservation of the FBBT together with its microvasculature will lead to recovery of biliary damage and prolonged preservation of bile ductules during the development of chronic liver allograft rejection. The interlobular bile ducts, portal bile ductules and extraportal biliary cells with and without microvessels were studied in sequential biopsies in five patients who fulfilled the Banff criteria of early chronic rejection (CR) (imminence group). Biopsies of CR patients (n = 12) served as controls. Biopsies were double immunostained with CD34 (microvessels) and cytokeratin 7 (biliary structures). Proliferation and proangiogenic activity were assessed with Ki67 and VEGF-A immunostaining. Severe damage of bile ducts in the imminence group did not progress to significant bile duct loss. This was associated with a high proliferative activity in all biliary structures and preservation of the microvascular compartment. VEGF-A expression was increased in all but the reperfusion biopsies. In conclusion, both regenerative activity of the FBBT and an intact microvascular compartment are associated with less damage of the biliary tree and could therefore be prerequisites for biliary regeneration. 相似文献
104.
臂丛神经卡压综合征的诊治 总被引:4,自引:0,他引:4
目的探讨位于臂丛神经及其前中斜角肌周围的神经卡压综合征的特点及其诊治方法。方法2003年7月~2006年1月,采用门诊收集病例,根据病情轻重分组,分别采用药物、局部封闭及手术方法治疗179例确诊为臂丛神经和(或)其属支卡压综合征的患者。其中采用药物、手法治疗89例;注射治疗74例,其中需要第二次注射32例;手术治疗16例,同时或分别进行双侧手术2例,需要第二次手术者1例。结果128例患者得到1个月~2年5个月随访。其中,药物手法治疗55例,症状均有不同程度改善或能维持现状。局部注射治疗58例(其中接受第二次注射者24例),2例出现心跳减缓,其余病例无并发症发生,VAS评分情况:1分2例,2分16例,3分20例,4分12例,5分3例,6分3例,7分2例;第二次注射结果:2分5例,3分16例,4分3例。手术治疗15例,其中10例术后症状得到明显改善,恢复工作。结论臂丛神经及其属支涉及其周围众多神经,可产生众多症状;明确病因后,治疗上以保守治疗为主,效果欠佳者采用手术治疗,均可取得较好疗效。 相似文献
105.
106.
107.
C Edward Hoffler Kurt D Hankenson Joshua D Miller Sukhinderdeep K Bilkhu Steven A Goldstein 《Journal of orthopaedic research》2006,24(8):1687-1698
To understand in situ behavior of osteocytes, we characterized a model of osteocytes in their native bone matrix and demonstrated real-time biologic activity of osteocytes while bending the bone matrix. Using 43 male Sprague-Dawley rats, dumbbell-shaped explants were harvested from stainless steel femoral implants after 6-12 weeks and incubated in culture medium or fixed. Sixteen specimens were used to determine bone volume density (BV/TV), volumetric bone mineral density (BMD) and histology for different implantation periods. Osteocyte viability was evaluated by L-lactate dehydrogenase (LDH) activity in 12 cultured explants. Confocal microscopy was used to assess tracer diffusion in three explants and changes in osteocyte pH of a mechanically loaded explant. From 6 to 12 weeks, explant BV/TV and volumetric BMD trended up 92.5% and 101%, respectively. They were significantly and highly correlated. Tissues were uniformly intramembranous and all bone cell types were present. Explants maintained LDH activity through culture day 8. Diffusion at 200 microM was limited to 1,209 Da. Explants appeared capable of reproducing complex bone biology. This model may be useful in understanding osteocyte mechanotransduction in the context of a physiologically relevant bone matrix. 相似文献
108.
Surender Kumar Yachha Rakesh Aggarwal S Srinivas Anshu Srivastava Sanjay K Somani Srivenu Itha 《Indian journal of gastroenterology》2006,25(3):132-135
BACKGROUND: We prospectively evaluated the usefulness of IgA tissue transglutaminase antibodies (IgA tTG) in the initial diagnosis of celiac disease (CD) and compared its diagnostic potential with that of IgA anti-endomysial antibodies (IgA EMA) and anti-IgA and IgG gliadin antibodies (AGA and AGG, respectively). METHODS: Sera of 23 untreated children fulfilling the revised ESPGHAN criteria for diagnosis of CD (Group I; mean age 10.8 y); 19 disease controls (Group II; mean age 8.5 y) presenting with chronic diarrhea, short stature or both; and 22 healthy children (Group III; mean age 8.8 y) were studied. These were tested in a blinded manner for AGA, AGG, IgA tTG (guinea pig as antigen) and IgA EMA. RESULTS: In Group I, IgA EMA was positive in 19, IgA tTG in 17, AGA in 14 and AGG in 17 patients. In Group II, these tests were positive in 1, 0, 2 and 14 patients, respectively and in Group III, in 0, 0, 0 and 1 child, respectively. Analyzing data from Group I and II, IgA EMA, IgA tTG, AGA and AGG had sensitivity rates of 83%, 74%, 61% and 74%, respectively; the specificity rates were 95%, 100%, 89% and 26%; positive predictive values were 95%, 100%, 88% and 55% and negative predictive values were 82%, 74%, 65% and 45%, respectively. CONCLUSION: IgA tTG is useful for the diagnosis of CD, with sensitivity and specificity rates comparable to those of EMA and this test is well suited for use in tropical countries like India. 相似文献
109.
Kevin L Taylor Rhonda K Oates Ron Grane Douglas W Leaman Ernest C Borden Daniel J Lindner 《Journal of interferon & cytokine research》2006,26(5):353-361
Interferon-alpha (IFN-alpha) has proved effective in the treatment of hemangiomas, hemangioblastomas, and Kaposi's sarcoma. To investigate the ability of IFNs to inhibit angiosarcoma, we used two transformed murine endothelial cell lines that form angiosarcomas in vivo. SVR and MS1-VEGF cell lines express oncogenic H-ras or vascular endothelial growth factor (VEGF), respectively. IFN-alpha1,8, which is active against murine and human cells, inhibited SVR and MS1-VEGF proliferation in vitro by 40% at 10(3) U/mL (p = 0.028). In vivo, IFN-alpha1,8 inhibited SVR tumor volume by 71% (p = 0.047) and MS1-VEGF volume by 79% (p = 0.003). Tumor-induced angiogenesis was decreased in SVR tumors by 52% (p = 0.005) and in MS1-VEGF tumors by 58% (p = 0.001). Sera from IFN-alpha1,8-treated mice bearing either SVR or MS1-VEGF tumors demonstrated a 5-fold increase in IP-10/CXCL10 (p = 0.001), an IFN-induced antiangiogenic protein. Both recombinant IP-10 and IFN-alpha1,8 inhibited human umbilical vein endothelial cell (HUVEC) vessel formation in the fibrin gel assay, a three-dimensional culture model of angiogenesis, by 56% at 25 ng/mL and 50% at 1.2 ng/mL, respectively (p < 0.001). An IP-10 blocking antibody restored vessel formation to 80% of untreated controls (p = 0.001). Given the magnitude of the in vivo response, these data suggested that the antitumor effects of IFN-alpha1,8 were likely mediated through angiogenesis inhibition rather than solely by direct inhibition of tumor cell proliferation. 相似文献
110.