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81.
“C”型曲线的中耳声学特性改变与鼓室积液的关系   总被引:10,自引:2,他引:8  
对40耳声导抗检查为“C”型曲线患耳进行中耳系统共振频率点测试并进行鼓室穿刺抽液,结果表明:共振频率点低于600Hz,患耳鼓室积液阳性率为82.1%,高于600Hz患者鼓室和液阳性率16.7%,提示依据鼓室导抗图和共振频率点测定可初步判断“C”型曲线患耳鼓室积液的可能.  相似文献   
82.
Ohne Zusammenfassung The online version of the original article can be found at  相似文献   
83.
用酶联亲合组化法对46例肺肿瘤细胞进行了雌激素受体(ER)和孕激素受体(PR)检测。同时测定14例肺瘤肿患者血清雌二醇(E_2)浓度。结果表明:肺肿瘤 ER 阳性率为36.9%,PR 阳性率为13.0%。阳性率与性别、病理类型及血浆 E_2浓度无关。认为肺癌的发生发展可能与雌激素有依赖关系,提示内分泌疗法可能会成为原发肺肿瘤的一种治疗手段。另用 ABC 法对上述46例肺肿瘤中的29例进行了花生凝集素受体(PNA-R)和麦胚凝集素受体(WGA-R)的检测,PNA-R 在腺癌大都为顶浆型分布,鳞癌和透明细胞癌则多为胞膜型分布。结果提示 PNA-R 是肺癌分化过程中的一种标志,对肺癌分型、预后判断有一定协助作用。同时将29例肺肿瘤 PNA-R 与 ER 状况作对比研究,探讨了二者之间的相关性及可能的发生机制。  相似文献   
84.
采用反相HPLC荧光测定法对大鼠肾脏N-乙酰氨基葡萄糖转移酶(GnT)Ⅲ活性测定时二价金属离子及氨基糖的影响进行了研究。结果表明:GnTⅢ必须有二价金属离子激活,最佳激活离子为Mn ̄(2+)离子,其次为Mg ̄(2+)离子;二协金属离子对GnTⅢ的激活作用依次为Mn ̄(2+)>Mg(2+)>Co(2+)>Ca ̄(2+)>Ni ̄(2+)>Ba ̄(2+)>Zn ̄(2+)。四种氨基糖(N-乙酰氨基葡萄糖GlcNAc,N-乙酰氨基半轧糖GaINAc,氨基葡萄糖GlcN,氨基半乳糖GalN),除GlcN使GnT活性增加外,其余三种对GnTⅢ均有不同程度的抑制作用。  相似文献   
85.
Advances in microsurgery have produced multiple options for microsurgical restoration of distal digital function. However, because of the complexity of most mutilating hand injuries, these possibilities can be readily overlooked. A surgical awareness of these options for "like" tissue transplantation is now necessary for complete mutilating hand injury care. These "minor" aesthetic and functional microsurgical procedures can be major factors in overall patient acceptance and utilization of the reconstructed hands.  相似文献   
86.
87.
While attempting to find a suitable crosslinking reagent for biopolymers, a naturally occurring proanthocyanidin (PA) obtained from grape seeds was selected to fix biological tissues. The cytotoxicity and crosslinking rate, reflected by the in vitro and in vivo degradation of fixed matrices has been studied. The shrinkage temperature of the fixed bovine pericardium increased from 66 to 86 degrees C. A cytotoxicity assay using fibroblast cultures revealed that PA is approximately 120 times less toxic than glutaraldehyde (GA), a currently used tissue stabilizer. In vitro degradation studies showed that fixed tissue was resistant to digestion by bacterial collagenase. Crosslinks between PA and tissues can be stabilized by decreasing the dielectric constant of the solution during storage. After subcutaneous implantation for periods ranging between 3 and 6 weeks, we found no apparent degradation of the GA- or PA-fixed tissues, whereas fresh tissue controls rapidly disintegrated. Beyond 6 weeks PA crosslinks began to degrade. More fibroblasts migrated and proliferated inside the PA-fixed implants compared with GA counterparts. Tissues crosslinked with PA manifested an enhanced collagen expression and deposition and did not calcify after implantation. GA, on the other hand, even after thorough rinsing continued to be cytotoxic, inhibited collagen synthesis and encouraged dystrophic calcification. Collagen matrices crosslinked with PA are expected to be of value in the design of matrices that will encourage cell ingrowth and proliferation, which are temporary in nature, and that are intended to regenerate or replace missing tissues, which can delay the biogradation of collagen. As such they should be of significant value in the emerging field of tissue engineering.  相似文献   
88.
The low density lipoprotein receptor-related protein (LRP) gene is a candidate gene for Alzheimer's disease (AD) due to its role as a receptor for apolipoprotein E (apoE), a major genetic risk factor for late-onset familial and sporadic AD. Recently, several studies have reported a correlation between a polymorphism (C766T) in exon 3 of LRP and AD. We examined this polymorphism in a Caucasian population of 225 neuropathologically confirmed cases with AD and 187 elderly cases without any AD neuropathological changes. We found that the exon 3 LRP C/C genotype was slightly but not significantly higher in the AD group when compared to the control group. A meta-analysis of previous studies revealed only a weak correlation of this polymorphism with AD (odds ratio 1.34, [95% CI 1.16-1.54], P < 0.0001). These data indicate that the polymorphism in exon 3 of LRP is only a minor risk factor for AD and that another locus on chromosome 12 is likely responsible for the associations observed in other studies.  相似文献   
89.

Background  

A sizeable number of HIV-infected patients receiving HAART do not maintain prolonged virologic suppression. We evaluated long-term HIV viral load (VL) responses to HAART as a risk factor for AIDS events (AE) that is independent of CD4 responses.  相似文献   
90.
Due to the sharp increase in liver transplant candidates and the subsequent shortage of suitable donor livers, an extension of the current donor criteria is necessary. Simple cold storage, the current standard in organ preservation has proven to be insufficient to preserve extended criteria donor livers. Therefore a renewed interest grew toward alternative methods for liver preservation, such as hypothermic machine perfusion and normothermic machine perfusion. These “new” preservation methods were primarily assessed in rat models, and only a few clinically relevant large animal models have been described so far. This review will elaborate on these alternative preservation methods. Anat Rec, 291:735–740, 2008. © 2008 Wiley‐Liss, Inc.  相似文献   
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