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91.
目的报道10例血清CA19-9明显升高的胆管良性疾病病例。方法回顾性分析2004年1月至2006年3月期间我院收治并经手术证实的10例血清CA19-9明显升高(>500U/ml)的胆管良性病变病例。结果患者中男4例,女6例,年龄30~85岁,CA19-9为532.32~12000.00U/ml,除1例患者CA125轻度升高外,其他患者血清CEA、CA125及AFP均正常。胆总管结石8例,肝内胆管结石1例,原发性硬化性胆管炎1例;除1例外均存在不同程度阻塞性黄疸。经治疗后8例CA19-9水平在30d内降至正常,另2例分别于术后2个月和3个月内降至正常。结论CA19-9在胆管恶性肿瘤诊断方面的意义仍需进一步研究。  相似文献   
92.
Mechanical waves in magnetic resonance imaging, which have been suggested for possible clinical applications, were analyzed with regard to imaging of the viscoelastic properties of large objects. The method is based on the Larmor frequency modulation caused by the application of mechanical waves. Possible clinical applications include all diseases that result in a change in the mechanical properties of biologic tissues (eg, atherosclerosis).  相似文献   
93.
乳腺癌组织中基质金属蛋白酶MMP-9和CD44v6表达及其意义   总被引:2,自引:2,他引:0  
目的探讨基质金属蛋白酶MMP-9和CD44v6在乳腺癌中的表达及其与乳腺癌侵袭、转移的关系.方法采用免疫组化方法对46例乳腺癌(10例导管内癌,36例乳腺浸润癌),10例乳腺增生组织MMP-9、CD44v6进行标记和分析.结果MMP-9和CD44v6在乳腺增生组织中几乎不表达,导管内癌、乳腺浸润癌表达率显著增高,各组间差异有显著性(P<0.05),而且MMP-9与CD44v6过表达与淋巴结转移有关.结论MMP-9和CD44v6的过表达在乳腺癌侵袭和转移中发挥重要作用,可作为乳腺癌侵袭和转移的重要分子学标志.  相似文献   
94.
Platelet additive solutions (PASs) were first developed in the 1980s, and continued to be improved over the following years. The use of PASs as replacement for plasma has a number of benefits, both for the quality of the platelet concentrates and for the patients. However, some PASs have been associated with a lower platelet yield in the PCs, a shorter storage time, and a lower increment in the patient when compared to PCs in plasma. A number of reformulations of the PASs have taken place to counteract these disadvantages. Most PASs use acetate as nutrient for the platelets, which has the benefit of generating bicarbonate when oxidized by the platelets, thus supplying its own buffering capacity. Alternatively, glucose is used, but may cause deterioration of pH in the stored PCs due to the formation of lactic acid. Addition of other buffering substances, such as phosphate, can be added to ensure maintenance of neutral pH. An important finding was the inhibiting effect of potassium and magnesium on platelet activation. The initially developed PASs lacked these two ingredients and showed reduced storage times of the PCs in PAS when compared to those stored in plasma. However, when these constituents are included in the PAS, storage time is similar and even exceeds those seen for PCs in plasma. Considerable research is done in further formulating the optimal PAS. Bicarbonate is being considered as buffer for these PASs. Also, L-carnitine appears to have a favorable effect on stored platelets, including a reduction of platelet metabolism, and inhibition of apoptosis. Another area of optimization is lowering of plasma content needed for maintaining platelet quality. Where current PASs still need at least 30% residual plasma, there is a trend towards lowering the plasma content to less than 5% with the newer PASs. Preservation of purinergic platelet receptor functionality by ADP-degrading activities in plasma appears to play an important role in this respect. Development of PASs are usually based on in vitro studies alone. It is important to realize that only clinical studies can give definitive answers about the quality of platelets stored in PASs. Sofar, only limited clinical evaluations have been published that either studied the effectiveness of platelets in initially-developed PASs, or were specifically done in combination with pathogen reduction technologies. Thus, PASs seem to be an excellent replacement for (part of) the plasma when producing PCs, and allow extended storage with maintenance of quality, but more clinical studies are needed to substantiate in vitro results.  相似文献   
95.
High frequency electrical stimulation by means of electrodes implanted into the brain has become an accepted technique for treatment of Parkinson's disease. The electrical field distribution normally inserted into the sub thalamic nucleus minimise abnormal brain activity. Square wave pulses of 1–3.6 V with duration of 60–90 μs at a frequency range of 130–185 pps are generally used. Every electrode unit consists of four cylindrical electrodes positioned in a row and can be switched on independently. This paper determines the contact impedance of the electrodes for different frequencies and proposes improvement to reduce the contact impedance between the electrodes and the brain. Measurements were performed by placing the electrodes in a tank filled with saline. Different frequencies were applied on two electrodes via a resistor. The current was measured through the resistor and the voltage was registered between one of the electrodes and a third non current carrying electrode. The obtained values were used to calculate the contact impedance. The result shows large contact impedance for the used frequency compared to the impedance of the treated tissue, which means that variation in contact impedance can result in variation in the electrical field applied to the tissue.  相似文献   
96.
本实验将赖型钩端螺旋体(简称钩体)DNA基因库的克隆pCX7制备成 ̄(32)P-重组DNA探针,对8个不同血清群的17株问号状钩体、双曲钩体PatocⅠ株以及细螺旋体3055株DNA进行打点杂交;同时用15种DNA片断进行限制性内切酶谱分析。结果表明,该重组DNA具有问号状钩体种(Species)特异性,但与不同问号状钩体之间的同源性程度有差别;限制性内切酶谱分析发现pCX7重组DNA片段长约1.7kb,具有1个Bg1Ⅱ识别位点和3个BstB1识别位点。  相似文献   
97.
In order to elucidate collagen metabolism in hepatocellular carcinoma (HCC) tissue, we compared levels of different potential markers of collagen metabolism and plasma transforming growth factor-β1 in patients with HCC and in patients with liver cirrhosis. Serum levels of prolyl hydroxylase and the tissue inhibitor of metalloproteinase-1 in patients with HCC were significantly higher than those in patients with liver cirrhosis and increased with the size of the HCC tumour, whereas the serum levels of procollagen type III propeptide and type IV collagen 7S domain were similar in the two groups. In HCC, the increased plasma transforming growth factor-β1 levels were closely correlated with serum levels of prolyl hydroxylase and the tissue inhibitor of metalloproteinase-1. These findings suggest that, in HCC tissue, the intracellular biosynthesis of collagen is enhanced, whereas the secretion of procollagen is disturbed and the degradation of collagen is suppressed by the excess production of the tissue inhibitor of metalloproteinase-1. The results also suggest that plasma transforming growth factor-β1 plays an important role in the altered metabolism of collagen in HCC.  相似文献   
98.
MMP-9和TIMP-1在实验性肺气肿大鼠肺组织中的表达及其意义   总被引:2,自引:0,他引:2  
目的研究基质金属蛋白酶(MMP-9)及其组织抑制因子(TIMP-1)在弹性蛋白酶所致肺气肿大鼠肺组织中的表达.方法雄性Wistar大鼠20只,随机分为两组:正常对照组和肺气肿模型组,每组10只.模型组大鼠气管内滴入弹性蛋白酶复制肺气肿模型.25d后,观察各组大鼠肺组织的病理改变,免疫组化方法观察肺组织MMP-9和TIMP-1中的蛋白表达情况.结果肺气肿模型组MMP-9和TIMP-1的表达与正常对照组相比明显增强(P<0.01),且MMP-9/TIMP-1比值失衡.结论MMP-9/TIMP-1失衡在肺气肿形成中起重要作用.  相似文献   
99.
Four 9-halo prostaglandin derivatives were designed and synthesized. Their structures were confirmed by IR, ^1HNMR, MS, etc. The effect on uterus contraction of rats was studied in vitro. It was found that compound β-Br seemed to be the most sensitive and β-Cl somewhat less, while α-Cl and α-Br had almost no action as compared with oxytocin (1 IU/ml).  相似文献   
100.
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