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991.
Daniel Klintman René Schramm Michael D Menger Henrik Thorlacius 《Journal of hepatology》2002,36(1):53-59
BACKGROUND/AIMS: This study was designed to examine the role of selectins and CD18 in leukocyte recruitment in hepatic injury induced by tumor necrosis factor-alpha (TNF-alpha) and galactosamine (Gal) in vivo. METHODS: Intravital fluorescence microscopy of the hepatic microcirculation was used to quantify leukocyte-endothelium interactions provoked by 24 h of systemic TNF-alpha/Gal challenge in rats. Hepatic injury was evaluated with liver enzymes. RESULTS: When administered after 24 h of TNF-alpha/Gal challenge, fucoidan, a selectin-function inhibitor, reduced leukocyte rolling by 69%, whereas firm adhesion was unaltered. In contrast, passive immunization against CD18 decreased leukocyte adhesion by 60%, whereas rolling remained unchanged. Notably, when administered prior to TNF-alpha/Gal, fucoidan attenuated both leukocyte rolling and adhesion, by 57 and 69%, respectively. Pretreatment with an anti-CD18 antibody decreased TNF-alpha/Gal-induced rolling and firm adhesion by 25 and 90%, respectively. Moreover, pretreatment with fucoidan and the anti-CD18 antibody both protected against TNF-alpha/Gal-induced increases in liver enzymes. For example, the pretreatments reduced alanine aminotransferase by 59 and 87%, respectively. CONCLUSIONS: Our data suggest that TNF-alpha/Gal-induced leukocyte rolling is selectin-mediated and a precondition for CD18-dependent firm adhesion in hepatic venules. Thus, reducing leukocyte recruitment by inhibition of selectins or CD18 may be useful to control TNF-alpha-induced liver injury. 相似文献
992.
目的:通过观察TβRⅡ,MMP-7及TIMP-2在HNPCC和散发性大肠癌中的表达,探讨其在HNPCC侵袭转移的生物学行为中的作用.方法:选取1980-05/2005-06空军总医院收治的HNPCC和散发性大肠癌各30例,应用免疫组化SP染色法检测其肿瘤组织中TβRⅡ,MMP-7,TIMP-2的表达情况.结合其相应临床病理资料进行分析TβRⅡ,MMP-7,TIMP-2表达在HNPCC侵袭转移中的作用.结果:TβRⅡ,MMP-7,TIMP-2在HNPCC组的阳性表达率分别为4 0.0%,46.7%,63.3%;而在散发性大肠癌组的阳性表达率为73.3%,86.7%,20.0%.散发性大肠癌组中MMP-7( ~ )/TIMP-2(-)比例明显高于HNPCC组.而其MMP-7(-)/TIMP-2( ~ )者则明显少于HNPCC组.TβRⅡ,MMP-7,TIMP-2的阳性表达率与肿瘤的大小和部位无关.而与肿瘤的侵犯深度和转移与否密切相关.侵犯浆膜外组织和有转移者的MMP-7的阳性表达率明显增高,而TβRⅡ,TIMP-2的阳性表达率则明显降低(P<0.05).在两组大肠癌中TβRⅡ与MMP-7呈正相关(r=0.735,P=0.000;r=0.792,P=0.000),TIMP-2与TβRⅡ(r=-0.582,P=0.001;r=-0.394,P=0.031)和MMP-7 (r=-0.473,P=0.008;r=-0.388,P=0.034)的表达均呈负相关.结论:TβRⅡ,MMP-7,TIMP-2在散发性大肠癌和HNPCC中的表达差异显著.TβRⅡ,MMP-7在散发性大肠癌中的表达率和表达强度明显高于HNPCC,而TIMP-2的表达结果则相反.因此,散发性大肠癌中MMP-7/TIMP-2的比例失衡明显高于HNPCC组. 相似文献
993.
994.
Spontaneous Rupture of the Spleen Secondary to Metastatic Hepatocellular Carcinoma: A Report of a Case and Review of the Literature 总被引:1,自引:0,他引:1
Yutaka Horie M.D. Takeaki Suou M.D. Chisato Hirayama M.D. Ren Nagasako M.D. 《The American journal of gastroenterology》1982,77(11):882-884
An extremely rare case of splenic rupture at the site of metastasis of hepatocellular carcinoma is reported. A 62-yr-old woman with hepatocellular carcinoma and its suspected metastasis to the spleen died of intraperitoneal hemorrhage. Autopsy disclosed a laceration of the spleen as the definitive cause of the hemorrhage. There were multiple nodules of metastatic hepatocellular carcinoma in the spleen, some of which were exposed at the lacerated portion of the splenic capsule. This may be the first report of a case of spontaneous rupture of the spleen secondary to metastatic hepatocellular carcinoma. Splenic rupture can he one of the causes of hemoperitoneum in patients with hepatocellular carcinoma. 相似文献
995.
To investigate the regulation of the synthesis and secretion of placental proteins-12 (PP12) and -14 (PP14) and PRL, explants and enriched preparations of stromal cells and gland cells obtained from 10 human early pregnancy decidua were preincubated in medium for 24 h (baseline), followed by incubation in medium with or without progesterone (0.02-32 mumol/L), hCG (10 and 100 ng/ml), or cAMP (0.25-1 mmol/L) in an atmosphere of 5% CO2-95% air at 37 C for another 96-120 h. Media were changed each 24 h, and PP12, PP14, and PRL levels were determined by RIA. Decidual explants, as well as their isolated cells produced detectable levels of PP12, PP14, and PRL in vitro. The gland cells synthesized and secreted about 30 times more PP14 than did stromal cells. After 96-120 h of incubation, the production of each protein by control cultures was increased 81-167% compared to the baseline (not significant). The secretion of these proteins in medium supplemented with progesterone or hCG was not significantly different from that in the control groups. 8-Bromo-cAMP significantly increased the secretion of PRL and PP12, but not PP14, by stromal cells compared to control values. We conclude that 1) PP14 is mainly produced by decidual gland cells; 2) progesterone at the concentrations used in our study does not stimulate production of PP12, PP14, and PRL in decidualized endometrium in vitro; 3) hCG does not stimulate the production of PP12 and PP14 in decidualized endometrium; and 4) 8-bromo-cAMP stimulates decidual stromal cell secretion of PRL and PP12. 相似文献
996.
Premenopausal women have a lower cardiovascular risk than men or postmenopausal women. However, this "female advantage" is lost in diabetes, a condition characterized by cardiac and vascular contractile dysfunction. This study was designed to compare the influence of diabetes on vascular and myocardial contractile function between genders. Adult male and female rats were made diabetic with streptozotocin (55 mg/kg) and maintained for 8 weeks. Tension development was examined in thoracic aortic rings and left ventricular papillary muscles. KCl-induced vasoconstriction, acetylcholine (ACh)-induced endothelium dependent or sodium nitroprusside (SNP)-induced endothelium-independent vasorelaxation, duration and maximal velocity of myocardial contraction and relaxation duration (TPT/RT90 and +/- VT) were similar between males and females. Diabetes augmented KCl-induced vasoconstriction at low doses, reduced SNP-induced vasorelaxation and had little effect on ACh-induced vasorelaxation in aortic rings from both genders. Diabetes prolonged TPT and RT90 in both genders, and reduced +/- VT in males but not females. Acute increase in extracellular Ca2+ (2.7 mM to 5.4 mM) shortened TPT in diabetic myocardium from both genders, whereas it had no effect on other myocardial mechanical indices in normal or diabetic groups of either gender. In addition, acute exposure to the Na+/K(+)-ATPase inhibitor ouabain shortened TPT/RT90 and enhanced +/- VT in myocardium from normal female, whereas it had no effect on male or diabetic myocardium. In conclusion, these data suggest that in the vasculature, there is no difference in diabetes-induced contractile dysfunction between genders, however several gender-specific differences are evident in the myocardium. 相似文献
997.
万古霉素等十种抗生素对耐苯唑西林葡萄球菌的体外活性比较 总被引:8,自引:0,他引:8
为了比较万古霉素等10种抗生素对1995年分离的95株耐苯唑西林的金黄色葡萄球菌和72株凝固酶阴性葡萄球菌的体外活性,用NCCLS颁布的琼脂稀释法测MIC。结果受检的10种抗生素中万古霉素的活性最好,其MIC50及MIC90分别为1mg/L及2mg/L,平均值为124mg/L;耐药率为0%。其次为壁霉素,其MIC50及MIC90分别为2mg/L及8mg/L,平均值为251mg/L;耐药率为2%。利福平MIC50及MIC90分别为0125mg/L及32mg/L,平均值为022mg/L;耐药率为14%。其它依MIC90的大小排序,为氧氟沙星,甲氧苄啶,红霉素,庆大霉素,磷霉素,磺胺甲恶唑等。用柱状图显示了前三种药的MIC值的分离,万古霉素具有良好的分散性,全部落在敏感区,且为单峰。结果表明万古霉素对MRSA和MRSCoN有良好的抗菌活性。 相似文献
998.
Potent and nontoxic antisense oligonucleotides containing locked nucleic acids 总被引:19,自引:0,他引:19
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Wahlestedt C Salmi P Good L Kela J Johnsson T Hökfelt T Broberger C Porreca F Lai J Ren K Ossipov M Koshkin A Jakobsen N Skouv J Oerum H Jacobsen MH Wengel J 《Proceedings of the National Academy of Sciences of the United States of America》2000,97(10):5633-5638
Insufficient efficacy and/or specificity of antisense oligonucleotides limit their in vivo usefulness. We demonstrate here that a high-affinity DNA analog, locked nucleic acid (LNA), confers several desired properties to antisense agents. Unlike DNA, LNA/DNA copolymers were not degraded readily in blood serum and cell extracts. However, like DNA, the LNA/DNA copolymers were capable of activating RNase H, an important antisense mechanism of action. In contrast to phosphorothioate-containing oligonucleotides, isosequential LNA analogs did not cause detectable toxic reactions in rat brain. LNA/DNA copolymers exhibited potent antisense activity on assay systems as disparate as a G-protein-coupled receptor in living rat brain and an Escherichia coli reporter gene. LNA-containing oligonucleotides will likely be useful for many antisense applications. 相似文献
999.
糖尿病患者心率变异性的临床观察及评价 总被引:4,自引:0,他引:4
用心率变异性(HRV)分析技术,观察糖尿病患者HRV时域的六项指标变化:①avgRR:RR间期平均值;②SDANN:4分钟RR平均值的标准差;③CV:变异系数;④SD:每4分钟RR间期标准差的平均值;⑤SDSD:SD的标准差;⑥rmSASD:每4分钟内相邻RR间期差值作均方根后的平均值。Ⅱ型糖尿病患者25例,正常对照组18例,两组年龄相似。结果表明,糖尿病组的SD,SDANN及rmSASD显著低于对照组,而avgRR无显著变化。为分析记录时间上的差异性,选择81例正常人,分成上午组(45例)与下午组(36例),除SDANN外,其余五项指标在上午组与下午组之间无显著差别。结论认为糖尿病患者的HRV显著减小,说明HRV对糖尿病有一定的临床应用价值。 相似文献
1000.