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1.
PGA指数和透明质酸在诊断慢性乙肝肝纤维化中的价值   总被引:1,自引:0,他引:1  
目的:寻找一种简便实用的诊断慢性乙型肝炎纤维化的方法。方法:以78例经肝穿刺病理证实的慢性乙型肝炎为对象,测定并比较了由PT、GGT、ApoA1组成的PGA指数和HA、LN、PⅢP、C-IV与肝内纤维化程度(S)和炎症活动度(G)的关系。结果:(1)LN、PⅢP、C-IV在轻度慢性乙肝时无明显升高,在中度慢性乙肝时明显高于正常,但与轻度慢性乙肝无差异,而PGA指数和HA不仅在轻度慢性乙肝时显著升高,而且在轻中度间差异明显.因重度慢性乙肝和活动性肝硬化时,五项指标均显著增高。(2)在G2-4期,HA、LN、PⅢP、C-IV均明显高升,但在G1期,只有PGA指数高于正常,且各期间差异显著。(3)在S1-2期,只有PGA指数、HA、C-IV明显上升,但C-IV的上升幅度远低于PGA指数和HA。(4)加以PGA>4.5或HA>200μg/L作为判断临界值,则两者判断肝纤维化的敏感性均>94%,精确性>91%,特异性>86%,如两者结合,则分别达到98.3%、95.2%和96.4%。结论:PGA指数和HA均是反映慢性乙型肝炎患者肝内纤维化程度的良好指标,两者联合检测则可达到最大的价值效益比。  相似文献   
2.
本文主要研究了无机玻璃纤维增强聚甲基丙烯酸甲酯(PMMA)/羟基磷灰石(HA)复合材料的制备及相关的性能测试,证明此复合材料性能稳定、物理机械强度高以及工艺简单,有良好的应用前景。  相似文献   
3.
Central activation of excitatory amino acid receptors has been implicated in neuropathic pain following nerve injury. In a rat model of painful peripheral mononeuropathy, we compared the effects of non-competitive NMDA receptor antagonists (MK 801 and HA966) and a non-NMDA receptor antagonist (CNQX) on induction and maintenance of thermal hyperalgesia induced by chronic constrictive injury (CCI) of the rat common sciatic nerve. Thermal hyperalgesia to radiant heat was assessed by using a foot-withdrawal test and NMDA/non-NMDA receptor antagonists were administered intrathecally onto the lumbar spinal cord before and after nerve injury. Four daily single treatments with 20 nmol HA966 or CNQX beginning 15 min prior to nerve ligation (pre-injury treatment), reliably reduced thermal hyperalgesia in CCI rats on days 3, 5, 7 and 10 after nerve ligation. Thermal hyperalgesia was also reduced in CCI rats receiving a single post-injury treatment with HA966 (20 or 80 nmol) or MK 801 (5 or 20 nmol) on day 3 after nerve ligation when thermal hyperalgesia was well developed. In contrast, a single post-injury CNQX (20 or 80 nmol) treatment failed to reduce thermal hyperalgesia or to potentiate effects of HA966 or MK 801 (5 or 20 nmol) on thermal hyperalgesia in CCI rats. Moreover, multiple post-injury CNQX treatments utilizing the same dose regime as employed for the pre-injury treatment attenuated thermal hyperalgesia but only when the treatment began 1 or 24 h (but not 72 h) after nerve ligation.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
4.
采用羟基磷灰石涂层股骨柄假体行全髋置换术的早期疗效   总被引:2,自引:1,他引:1  
目的总结采用羟基磷灰石(HA)涂层股骨柄假体行全髋关节置换术的早期疗效。方法2000年2月~2003年10月,采用钛合金HA涂层股骨柄假体行无骨水泥全髋关节置换术65例(70髋)。术前诊断:股骨颈骨折30例,骨关节炎15例,股骨头缺血性坏死9例,人工股骨头术后松动8例,类风湿性髋关节炎2例,髋关节融合1例。分别于术后1周、3个月、6个月,以后每年一次行髋关节功能和X线片检查,其中44例接受双能X线骨密度仪(DEXA)的骨密度(BMD)检查。结果术后X线片提示股骨柄假体的初始固定均符合优良标准。随访2~5.5年,平均3年。髋关节功能从术前Harris平均评分32分(25~52分)恢复至最后随访时的平均96分(85~100分),至今无一髋表现股区痛或需行翻修手术。术后1年内的X线片测量显示:<1.5mm下沉者7髋,其余均无假体下沉。至今无一例显示股骨近端或髓内骨溶解,也无一例显示假体松动。DEXA检查显示BMD在术后下降,然后迅速恢复,3~6个月后可达到正常或接近正常水平,其中Ⅱ、Ⅵ区的BMD增加速度最快,有时甚至高于对照侧。按Engh标准评定,全部患者均获骨性固定。结论近段HA涂层能增强股骨柄假体的初始固定,促进早期骨长入和骨性生物学固定,阻止聚乙烯磨屑的髓内移行和骨溶解,故用于无骨水泥全髋置换术的早期疗效满意。  相似文献   
5.
作者于1987年2月16日~1988年2月15日在四川五个点211 639人群中监测急性病毒性肝炎。其发病率为167.74/10万,其中甲型肝炎占24.51%;乙型肝炎占38.31%;非甲非乙型肝炎占24.51%,EB病毒和巨细胞病毒所致肝炎各占3.38%;混合感染占5.92%。病毒性肝炎中有14.93%重叠感染。发病高峰在春季。发病率,男:女=1.75:1。甲型肝炎20岁以下年龄组、乙型肝炎20~39岁年龄组的发病率明显高于其他年龄组,非甲非乙型较分散,5~19岁相对多一些,其他型别年龄组间无明显差异。355例急性病毒性肝炎患者中43.9%有接触史,36.6%有注射史。  相似文献   
6.
Cell culture-based influenza vaccine manufacturing is of growing importance. Depending on virus strains, differences in infection dynamics, virus-induced apoptosis, cell lysis and virus yields are observed. Comparatively little is known concerning details of virus–host cell interaction on a cellular level and virus spreading in a population of cells in bioreactors. In this study, the infection of MDCK cells with different influenza A virus strains in lab-scale microcarrier culture was investigated by flow cytometry. Together with the infection status of cells, virus-induced apoptosis was monitored. A mathematical model has been formulated to describe changes in the concentration of uninfected and infected adherent cells, dynamics of virus particle release (infectious virions, hemagglutinin content), and the time course of the percentage composition of the cell population.  相似文献   
7.
Summary The effectiveness of calcium antagonists on a chronic cerebral vasospasm after an SAH is still under debate. Calcium channel blockers such as nimodipine, nefedipine etc. can dilate spastic arteries by intrathecal administration, but not by systemic (iv or po) use. HA 1077 is a novel and potent calcium antagonist vasodilator which is considered to act by employing different mechanisms from the usual calcium channel blockers since it inhibits 1. calcium ionophore A 23187 induced contraction in arterial strips and 2. phenylephrine induced contraction in calcium free media, suggesting that its site of action is in the intracellular space. HA 1077 is water soluble and relatively stable in light.In the present study, the efficacy of HA 1077 was evaluated on dogs by using the spiral arterial strips in vitro and by angiography in vivo. In the arterial strips from the control dogs, a 50% relaxation of KCl (15 mM) induced contraction was obtained by a 10–6 M HA 1077 for the intracranial basilar and middle cerebral arteries, while a 10–5 M was needed to obtain the same effect for the extracranial common carotid and vertebral arteries, indicating that HA 1077 is more effective for the intracranial arteries. A vasospasm was produced by the two haemorrhage model of Varsoset al. The average angiographic diameter of the basilar artery was reduced to 60% of the control on SAH day 7. Intravenous infusion of HA 1077 (0.5–3 mg/kg/30 min) significantly dilated the spastic basilar artery (up to 20–30%), for over 2 hours. A fall in the systemic BP remained less than 20% during this time. Such spasmolytic effects by intravenous administration could not have been obtained with the usual calcium channel blockers. HA 1077 may be suitable for the treatment of a vasospasm in humans as well.  相似文献   
8.
Secretion of Igs and surface expression of HLA antigens was examined in lymphoid cells as a function of temp. Upon reducing the temp from 37 to 20 degrees C a progressive decrease in the secretion of Ig and surface expression of HLA antigens was noted. When the status of the oligosaccharides present on these glycoproteins was examined, conversion of high-mannose [endo-beta-N-acetylglucosaminidase-(Endo H) sensitive] to complex-type (Endo H resistant) oligosaccharides diminished with decreasing temp. At no time was an accumulation of Endo H resistant glycoproteins seen intracellularly. These results show that the phenomenon observed for synthesis and intracellular transport of viral glycoproteins in epithelial cells at reduced temp, namely intracellular accumulation of viral glycoproteins carrying complex sugar moieties, does not necessarily apply to glycoprotein transport in lymphoid cells. A difference in subcellular organization of epithelial and lymphoid cells may be responsible for this discrepancy.  相似文献   
9.
We present a mathematical model for pre-fusion interaction between an influenza virus and a healthy cell. Our model describes the role played by hemagglutinin (HA) protein clusters in bringing the viral membrane into close contact with the host cell membrane as a first step of the fusion process between the two membranes. The viral membrane is modelled as a lipid bilayer with bending rigidity. Using the calculus of variations, we compute the deformation of the viral membrane under the influence of HA protein clusters. Our numerical results support the hypothesis of dimple formation in the fusion site proposed in the literature. The asymmetric nature of the protein molecules due to various reasons such as tilting is the primary cause for the dimple formation. We discuss the effects of spontaneous curvature, the protein cluster radius, fusion-site size and the bending moment exerted by the protein cluster. We also examine the effects of membrane tension and the presence of a host cell on the dimple shape. Our results support previous experimental observations.  相似文献   
10.
多囊卵巢综合征高雄激素血症患者瘦素水平的检测及评价   总被引:1,自引:0,他引:1  
目的探讨多囊卵巢综合征高雄激素血症进行患者瘦素(Leptin)水平及其与睾酮(T)、体重指数(BMI)的关系.方法采用放射免疫分析法(RIA)检测53例PCOS患者血清瘦素水平,其中非肥胖组PCOS患者36例,正常对照30例;肥胖组PCOS患者17例,正常对照20例.结果肥胖组及非肥胖组PCOS高雄激素血症患者血清瘦素水平均明显高于相当体重指数的正常对照组,有显著差异(p均<0.01);两组瘦素水平分别与其睾酮水平进行相关性分析,均显著正相关(r=0.51,p<0.01和r=0.58,p<0.01);非肥胖组PCOS患者血清瘦素水平与其BMI相关分析显示,无相关性;肥胖组PCOS患者血清瘦素水平与其BMI进行相关分析,显著正相关(p=0.56,p<0.01).结论高瘦素血症是PCOS患者的内分泌特征之一,PCOS高雄激素血症的形成与高瘦素水平有关;超重或肥胖的PCOS高雄激素血症患者存在瘦素抵抗现象.  相似文献   
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