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姚刚  曹新岭  李涛 《中国全科医学》2022,25(12):1429-1434
背景 既往对肝癌微血管侵犯病理诊断的重要性重视不够,目前国内外缺乏对微血管侵犯统一的病理诊断标准,也未将微血管侵犯列为病理常规诊断指标。C反应蛋白/白蛋白比值(CAR)作为新型系统性炎性因子,与肝癌的增殖、侵袭转移等恶性生物学行为密切相关。 目的 探讨CAR预测单发小肝癌患者微血管侵犯的价值。 方法 选择2017年6月至2021年6月在新疆医科大学第一附属医院行肝切除术的单个、肿瘤直径≤5 cm的术后病理检查证实为肝癌的患者346例为研究对象。收集患者一般资料,并计算CAR。绘制CAR预测单发小肝癌患者微血管侵犯的受试者工作特征(ROC)曲线,并计算CAR的最佳诊断截点,根据CAR最佳诊断截点将患者进行分组,采用1∶1最近邻居倾向性评分匹配(PSM)法将Logistic模型估计的倾向性评分相近患者进行配对,得到两组间各临床特征比较均衡性较高的样本。比较匹配后两组患者微血管侵犯率,采用Logistic回归分析评估匹配前、后CAR对单发小肝癌患者微血管侵犯的预测价值。 结果 346例患者中微血管侵犯阳性131例(37.9%),微血管侵犯阴性215例(62.1%)。ROC曲线分析结果显示,CAR预测单发小肝癌患者微血管侵犯的灵敏度为82.9%,特异度为76.4%,ROC曲线下面积为0.787〔95%CI(0.697,0.877)〕,最佳诊断截点为0.03。根据CAR最佳诊断截点,将患者分为CAR<0.03组(A组,n=145)和CAR≥0.03组(B组,n=201)。采用1∶1最近邻居PSM法,共92对匹配成功,匹配后两组临床资料均衡。匹配后,B组患者微血管侵犯发生率〔43.5%(40/92)〕高于A组〔13.0%(12/92)〕(χ2=6.314,P=0.013)。采用3种Logistic回归分析结果显示,匹配前、后CAR均为单发小肝癌患者微血管侵犯的独立影响因素(P<0.05)。 结论 CAR作为新型系统性炎症指标,可用于预测单发小肝癌微血管侵犯,当CAR≥0.03时提示单发小肝癌微血管侵犯发生率较高。  相似文献   
3.
Protein and peptide conjugates have become an important component of therapeutic and diagnostic medicine. These conjugates are primarily designed to improve pharmacokinetics (PK) of those therapeutic or imaging agents, which do not possess optimal disposition characteristics. In this review we have summarized preclinical and clinical PK of diverse protein and peptide conjugates, and have showcased how different conjugation approaches are used to obtain the desired PK. We have classified the conjugates into peptide conjugates, non-targeted protein conjugates, and targeted protein conjugates, and have highlighted diagnostic and therapeutic applications of these conjugates. In general, peptide conjugates demonstrate very short half-life and rapid renal elimination, and they are mainly designed to achieve high contrast ratio for imaging agents or to deliver therapeutic agents at sites not reachable by bulky or non-targeted proteins. Conjugates made from non-targeted proteins like albumin are designed to increase the half-life of rapidly eliminating therapeutic or imaging agents, and improve their delivery to tissues like solid tumors and inflamed joints. Targeted protein conjugates are mainly developed from antibodies, antibody derivatives, or endogenous proteins, and they are designed to improve the contrast ratio of imaging agents or therapeutic index of therapeutic agents, by enhancing their delivery to the site-of-action.  相似文献   
4.
《Annales d'endocrinologie》2019,80(5-6):280-285
Resistance to thyroid hormones syndrome is defined as increased thyroxine (T4) and triiodothyronine (T3) concentrations associated with normal or sometimes increased thyrotropin (TSH) concentration. This is usually due to a pathogenic variant with loss of function of the gene coding for thyroid hormone receptor β (THRB). This discrepancy in thyroid hormones (TH) and TSH concentrations is also frequently observed in the presence of analytical interference, notably alteration of TH transport proteins in serum. During 2017, 58 samples were sent to our laboratory in the Angers University Hospital Rare Thyroid and Hormone Receptor Disease Reference Center in order to identify an etiology for discrepant TSH and TH results. We sequenced the genes involved in TH regulation, action and transport (THRB, THRA, SECISBP2, SLC16A, ALB, TTR, SERPINA7). Free T4 and free T3 assay were performed with a second immunoassay (Siemens ADVIA Centaur). A genetic cause of discrepancy in TH and TSH concentrations, with mutation in THRB, was found in 26% of cases (15/58). Biological interference due to TH serum transport protein variant was found in 24% (14/58) of cases. No pathogenic variants were found in the other genes studied. Biological interference was also suspected in 26% of cases without genetic variant, in which the biological discrepancy was not confirmed by a second analytical technique (15/58). Finally, no etiology for the biological discrepancy could be found in 24% of cases (14/58). Clinically, patients in whom biological discrepancy was due to analytic interference were more often asymptomatic, and patients with no identified etiology tended to be older. To limit diagnostic errors associated with the finding of discrepant TSH and TH, we recommend initially conducting a second thyroid function test (TSH, free T4 and free T3) with a different assay, and then screening for a genetic variant in gene coding for thyroid hormone receptor β (THRB) and the TH serum transport proteins (ALB, TTR, SERPINA7).  相似文献   
5.
目的比较自研注射用紫杉醇(清蛋白结合型,PAB)与原研注射用紫杉醇(清蛋白结合型,Abraxane)的体内抗肿瘤作用。方法建立小鼠H22、Lewis和RM-1肿瘤模型,荷瘤小鼠分别静脉注射13.4,20.0,30.0,45.0 mg·kg-1剂量的PAB和20.0和(或)30.0 mg·kg-1剂量的Abraxane,比较给药后PAB组与Abraxane组的抗肿瘤作用。结果PAB 13.4,20.0,30.0,45.0 mg·kg-1剂量组均能显著抑制H22肿瘤生长,PAB 20.0 mg·kg-1剂量组与等剂量的Abraxane组比较对H22肿瘤地抑制作用差异无统计学意义。PAB 20.0,30.0,45.0 mg·kg-1剂量组可剂量依赖性地抑制Lewis和RM-1肿瘤生长,PAB和Abraxane对C57雌性荷瘤小鼠的最大无毒剂量均为20.0 mg·kg-1。PAB各剂量组与等剂量的Abraxane组比较,对RM-1和Lewis肿瘤生长的抑制作用和对荷瘤小鼠的毒性均差异无统计学意义。结论相同给药剂量下,PAB的体内抗肿瘤作用和毒性与原研品Abraxane相同。  相似文献   
6.
Pressure ulcers (PUs) are a common problem in critically ill patients admitted to the intensive care units (ICUs) and they account for more than 70% of patients with low serum albumin at admission. The aim of this study was to test the efficacy of intravenous administration of albumin in patients with low serum albumin < 3·3 g/dl. In a 1‐year period, a total of 73 patients were admitted to the ICU (males 45, 61·64% and females 28, 38·36%); of these, 21 patients were admitted with hypoalbuminaemia (serum albumin < 3·3 g/dl) and randomised into two groups: 11 patients were treated with 25 g intravenous albumin for the first 3 days within the first week of ICU stay (group A) and 10 patients did not receive albumin (group B). Three patients (27·27%) showed the onset of PUs in group A, whereas seven patients (70%) showed the onset of PUs within the first 7 days of stay in group B. Moreover, ulcers of group B were more severe than those of group A. This study shows that intravenous administration of albumin reduces the onset of PUs in patients admitted to the ICU and in some cases it also reduces the risk of progression to advanced stages of PUs.  相似文献   
7.
Radioembolization (RE) is a selective internal radiotherapy technique in which yttrium-90 blended microspheres are infused through the hepatic arteries. It is based on the fact that primary and secondary hepatic tumors are vascularized mostly by arterial blood flow whereas healthy hepatocytes obtain their blood supply mostly from the portal network. This enables high radiation doses to be delivered, sparing the surrounding non-malignant liver parenchyma. Most of the complications are caused by unexpected particles passing into the gastrointestinal tract through branches originating from the main hepatic arterial supply. Knowledge of this hepatic arterial network and of its variations and the technical considerations this raises are required in preparation for treatment. This work describes the specific anatomical features and techniques for this anatomy through recent literature illustrated by cases from our own experience.  相似文献   
8.
目的 探讨二十碳五烯酸(eicosapentaenoic acid,EPA)对人白蛋白诱导的人近端肾小管上皮细胞(HK-2)发生转分化的干预作用.方法 体外培养人HK-2细胞,随机分为6组:A组,空白对照组(未加任何刺激物);B组,单纯EPA组(加入30 μmol/L EPA);C组,血白蛋白(albumin,Alb)诱导组(加入5 mg/ml Alb);D组,低剂量EPA干预组(5mg/ml Alb+ 10 μmol/L EPA);E组,中剂量EPA干预组(5mg/ml Alb+ 30 μmol/L EPA);F组,高剂量EPA干预组(5 mg/ml Alb+ 50μmol/L EPA).细胞免疫荧光检测E钙黏蛋白(E-cadherin)、α平滑肌肌动蛋白(α-smooth muscle ac-tin,α-SMA)的表达;ELISA法检测纤维连接蛋白(fibronectin,FN)的水平;采用RT-PCR检测转化生长因子β1(transforming growth factor β1,TGF-β1)的mRNA表达.结果 与A组比较,B组TGF-β1mRNA、α-SMA、FN、E-cadherin表达均无统计学差异(P>0.05);C组TGF-β1 mRNA、α-SMA、FN较其他各组表达明显增高(P<0.05),而E-cadherin表达明显下降(P<0.05).与C组比较,D组、E组、F组TGF-β1 mRNA、α-SMA、FN表达逐渐下降,两组间比较差异有统计学意义(P<0.05);E-cadherin的表达逐渐增高,各组间比较差异有统计学意义(P<0.05).提示EPA可显著抑制Alb刺激人肾小管上皮细胞表达E-cadherin、α-SMA,同时下调上清液中FN水平,且其抑制作用的强弱与EPA浓度密切相关.EPA还明显下调了Alb刺激后TGF-β1的表达.结论 一定浓度的人白蛋白可以诱导体外培养的HK-2细胞发生转分化;EPA可一定程度上抑制白蛋白诱导HK-2发生转分化过程,且呈剂量依赖性.  相似文献   
9.
白蛋白微球经颈外动脉灌注后的体内分布及降解速度   总被引:2,自引:1,他引:2  
目的 :探讨作为药物载体的白蛋白微球 (AMS)经颈外动脉灌注后在体内的分布及降解速度 ,以及栓塞血管再通时间 ,为AMS的安全性提供依据。方法 :经家兔颈外动脉灌注以12 5 I标记的平均粒径 56.3 μm的白蛋白微球后 ,测定局部组织及全身脏器内的放射剂量。用 760ml/L的泛影葡胺行家犬颈外动脉造影观察AMS灌注后末梢血管再通时间。结果 :微球经颈外动脉灌注后 92 .2 3 %集中于头颈局部组织内。微球对颈外动脉的微小分枝有明显的栓塞作用 ,栓塞的血管在 7~ 9d内再通。结论 :AMS可作为药物的缓释载体  相似文献   
10.
目的探究术前血小板淋巴细胞比值(PLR)、中性粒细胞淋巴细胞比值(NLR)及白蛋白球蛋白比值(AGR)在评估乳腺癌患者预后中的价值。 方法选取2013年1月至2017年12月收治的1184例浸润性乳腺癌女性患者为浸润性乳腺癌组,随机选取仅患乳腺纤维腺瘤的患者279例为乳腺纤维腺瘤组。收集患者一般资料、术后病理资料、血型、术前外周血血小板、中性粒细胞、淋巴细胞数量以及血清白蛋白和球蛋白水平,并计算得出PLR、NLR及AGR。应用受试者功能特征曲线下面积来评估三者预测乳腺癌患者预后的能力。本研究使用SPSS 20.0及MedCalc软件进行统计学分析和绘图,P<0.05代表差异具有统计学意义。 结果浸润性乳腺癌患者的术前PLR及NLR均值显著高于乳腺纤维腺瘤患者(P<0.05),而AGR低于乳腺纤维腺瘤患者(P<0.05)。Cox比例回归风险分析显示,患者的诊断年龄、PLR、NLR、AGR、肿瘤直径、组织学分级、阳性淋巴结个数和分子分型均为乳腺癌的预后危险因素(P<0.05)。ROC曲线分析结果得出,PLR、NLR及AGR的最佳诊断临界值分别为147.4、2.9及1.7。应用术前PLR(AUC=0.796,P<0.001)、NLR(AUC=0.716,P<0.001)及AGR(AUC=0.748,P<0.001)预测乳腺癌患者预后均有价值,且PLR价值更高。 结论术前PLR、NLR及AGR对乳腺癌患者预后的判断均具价值,三者相比,PLR价值更高,有望成为判断乳腺癌患者预后的补充指标。  相似文献   
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