肾乏脂性血管平滑肌脂肪瘤与三种常见病理类型肾癌的CT鉴别诊断

目的 探讨CT平扫征象及CT动态增强在鉴别乏脂性血管平滑肌脂肪瘤（angiomy-olipoma with minimal fat,AMLmf）与三种常见病理类型肾癌的应用价值。方法 选取83例肾脏实性肿块,其中15例经病理确诊为AMLmf,15例经病理确诊为肾脏乳头状细胞癌（PRCC）,27例经病理确诊为肾脏透明细胞癌（CCRCC）,26例经病理确诊为肾脏嫌色细胞癌（ChRCC）。83例患者术前均行CT平扫及三期动态增强检查,分别测量肿块实性区域平扫及三期动态增强CT绝对值,随后计算平扫与增强各期之间CT绝对值,三组（乏脂性AML与乳头状细胞癌、乏脂性AML与透明细胞癌、乏脂性AML与嫌色细胞癌）病例各期CT绝对值比较行单因素方差分析;四类病例分别观察病灶平扫密度是否均匀、强化密度是否均匀、是否囊变、有无星芒状瘢痕、有无劈裂征、有无钙化,随后采用χ2检验或Fisher确切概率法分析。结果AMLmf皮质期-平扫CT绝对值、排泄期-实质期CT绝对值均显著大于PRCC,实质期-皮质期CT绝对值显著小于PRCC,差异有统计学意义（P<0.05）;AMLmf皮质期-平扫CT绝对值、实质期...     

肾透明细胞癌和乏脂肪血管平滑肌脂肪瘤CT鉴别诊断分析

目的 探讨CT在肾透明细胞癌与乏脂肪血管平滑肌脂肪瘤的诊断与鉴别中应用价值。方法 分析40例肾透明细胞癌和25例肾乏脂肪血管平滑肌脂肪瘤患者的临床资料及CT扫描结果,探讨肾透明细胞癌与肾乏脂肪血管平滑肌脂肪瘤的CT诊断与鉴别诊断。结果 对比肾透明细胞癌患者与乏脂肪血管平滑肌脂肪瘤患者在平扫和各期增强扫描的CT值可以发现,在皮质期和肾盂期肾透明细胞癌患者的CT值明显高于乏脂肪血管平滑肌脂肪瘤患者,且差异具有统计学意义。对比两组肿瘤的CT常规征象可以发现肿瘤强化是否均匀及肿瘤强化方式在鉴别肾透明细胞癌和乏脂肪血管平滑肌脂时差异具有统计学意义,乏脂肪血管平滑肌脂表现为强化均匀的概率高于肾透明细胞癌,肾透明细胞癌多表现为快进快出的强化方式,而乏脂肪血管平滑肌脂多表现出延迟强化的特点。结论 平扫期高密度及皮髓期、皮质期、肾盂期强化数值〈120HU是乏脂肪血管平滑肌脂肪瘤最具诊断价值的CT特征。     

肾脏上皮样血管平滑肌脂肪瘤的CT表现及鉴别

目的 探讨肾脏上皮样血管平滑肌脂肪瘤(EAML)的CT表现及其与肾透明细胞癌(ccRCC)、肾血管平滑肌脂肪瘤(AML)的鉴别诊断.方法 回顾性分析经病理证实的EAML 28例、ccRCC 32例、AML 22例患者的CT征象并运用随机森林模型(RF)进行鉴别诊断.结果 EAML 28例中,男7例,女21例.平均发病年龄为42.5岁.25例发生在单侧肾脏;24例为单发,15例可见脂肪成分.CT平扫、增强动脉期及静脉期CT值分别为43.8HU、92.0 HU、77.0 HU.增强动静脉期CT差值12.8 HU.4例出现粗大血管.EAML与ccRCC进行鉴别诊断,其RF准确率为97.30％,EAML无囊变,约50％病例中含脂肪成分,发病年龄为42.5岁,平扫CT值为43.8 HU,动静脉期CT值差值为12.8 HU.约94％ ccRCC发生囊变,无脂肪,发病年龄为57.8岁,平扫CT值为36.7 HU,动静脉期CT值差值为27 HU.EAML与AML进行鉴别诊断,其RF准确率为70.97％:EAML较AML发病年龄年轻,肿瘤直径大,动静脉期CT值差大.结论 EAML主要发生在青年女性,平扫CT值较肾实质高,呈快进-慢出强化方式.EAML与ccRCC鉴别诊断主要从囊变、脂肪、年龄、平扫CT值、动静脉期CT值差值进行鉴别.EAML与AML主要从静脉期CT值、动脉期CT值、年龄、肿瘤直径、动静脉期CT值差值鉴别.     

多层螺旋CT鉴别诊断肾脏混合性上皮和间质肿瘤与囊性肾癌

目的探讨肾脏混合性上皮和间质肿瘤与囊性肾癌的多层螺旋CT(MSCT)表现及鉴别诊断要点,以提高二者术前影像诊断的准确性。资料与方法采用盲法研究,回顾性分析6例肾脏混合性上皮和间质肿瘤及14例囊性肾癌的MSCT表现,并与手术病理结果进行对照。结果 6例肾脏混合性上皮和间质肿瘤均为囊实性病变,但实性成分多少不等;其中BosniakⅢ型5例,BosniakⅣ型1例。14例囊性肾癌中,8例为透明细胞癌囊变,BosniakⅢ型7例,BosniakⅣ型1例;6例为多房性透明细胞性肾细胞癌,均为BosniakⅡF型。增强扫描示:肾脏混合性上皮和间质肿瘤实性部分在皮髓期呈轻度或中等程度强化,并随时间延迟强化程度增加;多房性透明细胞性肾细胞癌皮髓期菲薄间隔轻至中度延迟强化;7例BosniakⅢ型透明细胞癌囊变,皮髓期增厚间隔明显强化,1例BosniakⅣ型透明细胞癌囊变增厚间隔及结节皮髓期显著强化,二者强化程度较高,实质期强化程度均减退。结论肾脏混合性上皮和间质肿瘤囊性肾癌MSCT鉴别诊断有一定困难,但肿瘤实性成分的多少、间隔的形态以及增强方式可以为诊断及鉴别诊断提供依据。     

肾癌囊性改变的CT表现

目的：探讨肾癌囊性改变的CT表现特点,并与病理对照分析,以提高对此类肾癌的鉴别能力。资料与方法回顾性分析经手术病理证实的44例囊性改变肾癌,包括多房囊性肾癌10例、透明细胞癌21例、乳头状细胞癌13例,比较3组病例的CT征象。结果10例多房囊性肾癌均呈多房性改变,囊液平均CT值为（15.8±5.6) HU,囊壁及分隔较薄,4例壁结节直径>5 mm,8例囊壁及间隔呈早期中度强化。21例透明细胞癌中,9例呈多房性改变,囊液平均CT值为（32.5±6.7）HU,囊壁及间隔较厚,19例壁结节直径>5 mm,20例呈“快进快出”明显强化。13例乳头状细胞癌中,4例呈多房性改变,囊液平均CT值为（26.1±5.6）HU,囊壁及间隔较厚,12例壁结节直径>5 mm,12例呈轻至中度延迟强化。结论肾癌囊性改变的CT表现具有特征性,肿瘤有无假包膜、囊液CT值、囊壁及分隔厚度、附壁结节大小、边界及强化方式均有利于其鉴别诊断。     

35例不同病理亚型的肾癌螺旋CT分析

目的:探讨肾癌不同病理亚型的CT表现,为临床判断预后及制定治疗方案提供依据.方法:对35例病理证实的肾癌CT平扫及动态扫描图像行回顾性分析,总结肾癌不同病理亚型的CT特征.结果:本组透明细胞癌29例,乳头状癌3例,嫌色细胞癌3例,透明细胞癌的囊变坏死率(25/29)及强化幅度明显高于其他两个亚型,属富血供肿瘤,具快进快出强化方式,而乳头状癌及嫌色细胞癌为相对乏血供肿瘤,呈轻中度均匀或不均匀强化.结论:肾癌的螺旋CT表现和病理分型有一定相关性.     

MDCT动态增强扫描对肾透明细胞癌的诊断价值

目的:探讨多层螺旋CT(MDCT)动态增强扫描CT对肾透明细胞癌(CCRCC)的诊断价值。方法:回顾性分析103例手术病理证实的CCRC的多期MDCT表现。结果:103例CCRC共有病灶111个,MDCT平扫100个(100/111,90.1%)瘤灶表现为不均匀的等、稍低或高密度,增强扫描皮髓期102个(102/111,91.9%)肿瘤明显不均匀强化,强化最明显处与临近肾皮质相似或高于正常肾皮质,肾实质期病变强化程度降低。结论:CCRCC为富血供肿瘤,动态增强CT皮髓期肿瘤强化与肾皮质相仿或高于肾皮质,具有一定特征性,可与其他亚型肾细胞癌鉴别。     

≤3 cm 肾外型透明细胞癌与乏脂肪血管平滑肌脂肪瘤的 CT 鉴别

目的：探讨长径≤3 cm 且病灶中心位于肾轮廓外的肾透明细胞癌(CCRCC)与乏脂肪血管平滑肌脂肪瘤(AML)的 CT特征,比较两者的影像学异同点。方法回顾性分析经手术病理证实的6例 CCRCC 和18例乏脂肪 AML,对其 CT 形态学特征、CT 平扫及增强 CT 值进行差异性分析。结果2组病灶的长径、形态、早期排泄期 CT 值及早期排泄期强化幅度差异无统计学意义(P >0.05)。病灶内囊变坏死差异有统计学意义(P <0.05)。病灶的平扫密度、强化均匀性、假包膜征象及平扫 CT 值、皮髓质交界期 CT 值、皮髓质交界期强化幅度差异有显著统计学意义(P <0.001)。结论病灶内囊变坏死、平扫密度、强化均匀性、假包膜征象、平扫 CT 值、皮髓质交界期 CT 值及强化幅度对 CCRCC 与乏脂肪 AML 的鉴别诊断起重要作用。     

多期相CT对乳头状肾细胞癌亚型的鉴别诊断

【摘要】目的：探讨多期相CT对乳头状肾细胞癌（PRCC）亚型的鉴别诊断价值。方法：回顾性分析2014年10月-2018年5月经病理确诊的33例PRCC患者的多期相CT影像资料。所有病例均行CT平扫、三期增强扫描,分析不同亚型在临床指标、CT影像特征、多期相CT值等方面的差异。结果：Ⅱ型PRCC的病理学分期及分级均显著高于Ⅰ型（T3+T4期肿瘤,31.8% vs 9.1%;高级别肿瘤,54.5% vs 9.1%）（P＜0.05）,两型在性别、年龄、高危因素、肿瘤最大径等方面无明显差异。两型在形态、边界、异质性、CT分型、集合系统受累、囊变坏死等方面有显著差异（P＜0.05）,Ⅱ型病灶主要呈分叶状（54.5%）,边界模糊（63.6%）、密度不均（95.5%）,易浸润性生长（50%）、常伴集合系统受累（40.9%）和囊变坏死（81.8%）,在钙化、淋巴结增大、静脉癌栓形成等方面差异无统计学意义。Ⅰ、Ⅱ型皮髓质期净增CT值分别为（17.18±17.60）HU、（38.91±22.31）HU,Ⅰ、Ⅱ型实质期净增CT值分别为（26.45±12.06）HU、（40.00±18.96）HU,两种亚型间差异均具有统计学意义（P＜0.05）,平扫、增强三期、延迟期净增CT值及绝对洗脱率差异无统计学意义。结论：多期相CT对PRCC亚型的鉴别诊断有一定帮助。     

动态增强CT检查对肾上腺腺瘤与非腺瘤的鉴别诊断价值

目的探讨动态增强CT检查技术对肾上腺腺瘤与非腺瘤的鉴别诊断价值并优选出有意义的参数，以进一步明确两者的鉴别诊断标准。资料与方法对44例共49个肾上腺肿瘤先平扫再行动态增强CT检查，观察以肿瘤的CT绝对值、绝对开始廓清率及相对开始廓清率作为标准鉴别肾上腺腺瘤与非腺瘤的诊断价值。结果延时3min，以36％的绝对开始廓清率或35％的相对开始廓清率分别与CT绝对值58HU相结合作为标准，对腺瘤有较高的诊断价值，对于腺瘤中的乏脂质性腺瘤与非腺瘤的鉴别诊断也具有同样的价值。结论以肿瘤的廓清率与延时增强后的CT绝对值作为联合标准，能明显提高腺瘤的诊断价值。     

Cell Cycles in Cell Hierarchies

Summary

In the replacing tissues of the body, namely the bone marrow, testis, and the surface epithelia with their appendages, cell replacement would appear to be achieved using an hierarchically organized proliferative compartment with relatively few ultimate stem cells producing dividing transit cells which eventually differentiate and mature into the functional cells of the tissue. The cell cycle times of the various constituents of the hierarchy differ, and the stem cells apparently have a longer cell cycle than the transit cells. There may be variations in the cell cycle as cells pass through the transit population in some cases, e.g. in the bone marrow, while in others the cycle time remains fairly constant, e.g. in the testis.

The difference in the cell cycle time between stem cells and transit cells is not completely unequivocal, and there is little or no difference in cycle time in the epithelium on the dorsal surface of the tongue while in other cases the experimental evidence for long stem-cell cycles is somewhat imprecise. However, the epithelium in the small intestine and the spermatogonia in the testis have been fairly extensively studied and here the evidence clearly shows a lengthening of the cell cycle as more primitive cells are considered.     

Cell Tracking

Cell based therapies such as stem cell therapies or adoptive immunotherapies are currently being explored as a potential treatment for a variety of diseases such as Parkinson's disease, diabetes or cancer. However, quantitative and qualitative evaluation of adoptively transferred cells is indispensable for monitoring the efficiency of the treatment. Current approaches mostly analyze transferred cells from peripheral blood, which cannot assess whether transferred cells actually home to and stay in the targeted tissue. Using cell-labeling methods such as direct labeling or transfection with a marker gene in conjunction with various imaging modalities (MRI, optical or nuclear imaging), labeled cells can be followed in vivo in real-time, and their accumulation as well as function in vivo can be monitored and quantified accurately. This method is usually referred to as "cell tracking" or "cell trafficking" and is also being applied in basic biological sciences, exemplified in the evaluation of genes contributing to metastasis. This review focuses on principles of this promising methodology and explains various approaches by highlighting recent examples.     

全能干细胞与潜能再生细胞的实验研究进展

全能干细胞(totipotent stem cell,TSC)和潜能再生细胞(potential regenerative cell,PRCs)在实现各组织器官的原位再生,修复或改善损伤组织和器官的结构及功能方面发挥着重要作用,是目前医学领域研究的热点。笔者根据自身研究经验,并通过查阅大量文献资料,综述了全能干细胞与潜能再生细胞的生理作用,旨在为再生医学的后续研究提供一定的方向与思路。     

Cell adhesion-mediated radioresistance revisited

Purpose: Integrin-mediated adhesion of cells to proteins of the extracellular matrix modulates the cellular response to ionizing radiation in vitro. This mechanism might be in part causative for radiation and chemoresistance phenotypes in tumor cells.

Materials and methods: A PubMed database search was performed and the data were summarized with a focus on cell adhesion-mediated radioresistance (CAM-RR).

Results: Integrins and their associated downstream signaling pathways as well as cooperative interactions of integrins with receptor tyrosine kinases mediate defensive mechanisms that aggravate the therapeutic eradication of tumor cells by radiotherapy.

Conclusions: A better knowledge of the molecular composition and function of the multiprotein, multifunctional cell-matrix interactions mediating complexes termed focal adhesions may point at significant differences between normal and tumor cells, which could foster the development of novel targeted therapies in radiotherapy.     

扩散加权成像对非透明细胞肾癌亚型的鉴别诊断价值

目的 探讨扩散加权成像(DWI)表观扩散系数(ADC)值对非透明细胞肾癌亚型的鉴别诊断价值.资料与方法 经手术病理证实的48例非透明细胞肾癌患者,术前行DWI检查(b=0、800 s/mm2)测定病变ADC值,比较不同亚型非透明细胞肾癌ADC值的差异.结果 48例共48个病灶,直径(3.8±2.3) cm,其中肾嫌色细胞癌(CRCC) 20例,乳头状肾细胞癌(PRCC) 28例(Ⅰ型18例,Ⅱ型10例).CRCC的ADC值为(0.994±0.184)×10-3 nnm2/s,PRCC的ADC值为(0.860±0.114)×10-3 mm2/s,差异有统计学意义(P＜0.01); PRCC Ⅰ型ADC值为(0.908±0.085)×10-3 mm2/s,Ⅱ型ADC值为(0.775±0.113)×10-3 mm2/s,差异有统计学意义(P＜0.01); CRCC和PRCCⅡ型ADC值差异有统计学意义(P＜0.01),CRCC和PRCC Ⅰ型ADC值差异无统计学意义(P＞0.05).结论 当b=800 s/mm2时,ADC值可以鉴别CRCC和PRCCⅡ型,但不能鉴别PRCC Ⅰ型和CRCC.ADC值对鉴别非透明细胞肾癌亚型有一定帮助,但鉴别诊断效能不高.     

Cell adhesion-mediated radioresistance revisited

PURPOSE: Integrin-mediated adhesion of cells to proteins of the extracellular matrix modulates the cellular response to ionizing radiation in vitro. This mechanism might be in part causative for radiation and chemoresistance phenotypes in tumor cells. MATERIALS AND METHODS: A PubMed database search was performed and the data were summarized with a focus on cell adhesion-mediated radioresistance (CAM-RR). RESULTS: Integrins and their associated downstream signaling pathways as well as cooperative interactions of integrins with receptor tyrosine kinases mediate defensive mechanisms that aggravate the therapeutic eradication of tumor cells by radiotherapy. CONCLUSIONS: A better knowledge of the molecular composition and function of the multiprotein, multifunctional cell-matrix interactions mediating complexes termed focal adhesions may point at significant differences between normal and tumor cells, which could foster the development of novel targeted therapies in radiotherapy.     

Cell death and tendinopathy

Apoptosis and necrosis are presently recognized as the two major types of physiological and pathological cell death. Apoptosis is a tightly regulated cell deletion process that differs morphologically and biochemically from necrotic cell death. Tendinopathy is defined as a tendon injury that originates from intrinsic and extrinsic etiological factors. Excessive apoptosis has recently been described in degenerative tendon. The increased number of apoptotic tendon cells in degenerative tendon tissue could affect the rate of collagen synthesis and repair. Impaired or dysfunctional protein synthesis may lead to weaker tendon tissue and eventually increase the risk for tendon rupture. Clearly, there are many details to insert into this pathway, but there is hope that if the fine details of the pathway can be fleshed out, then strategies may be able to be developed to break the cycle at one or more points and prevent or treat tendinopathy more effectively.     

Relationship between Cell Survival and Heat-stress Protein Synthesis in a Drosophila Cell Line

Summary

Heat-stress protein (hsp) kinetics and clonogenic survival were studied at 33, 37 and 42°C in a continuous Drosophila cell line, WR69-DM-1. Induction and repression of hsp were temperature-dependent and independently modulated. The subsequent cell-survival curves were complex; however, survival generally decreased in a time- and temperature-dependent manner during continuous heating at 33, 37 or 42°C. Constant 33°C heating induced five hsp at 90, 72, 70, 24 and 19 kilodaltons (kDa). A 30 min 33°C heat dose led to thermotolerance after 1, 3 or 6 h incubations at 28°C. The hsp synthesized after this dose were quickly repressed, suggesting the cells were able to respond to this stress. Increasing the challenge temperature to 37°C induced three additional hsp at 34, 22 and 14 kDa, but hsp synthesis did not lead to thermotolerance over the 6 h interval. The number and intensity of hsp synthesized was higher and repression was much slower than at 33°C. Heating at 42°C inhibited all protein synthesis, and thermotolerance was not observed. Direct survival data are critical to understanding the role and function of hsp in Drosophila thermotolerance since the relevance of information on number and kinetics of hsp synthesis and their subsequent localization is dubious without it.