胃肠道间质瘤的CT诊断

目的分析胃肠道间质瘤(GIST)的CT表现特点,探讨CT对该肿瘤的诊断价值。方法回顾性分析经手术病理证实的GIST 25例,术前均行CT平扫和(或)增强检查。结果肿瘤发生于胃部16例,空肠4例,食管1例,回肠3例,直肠1例,病灶多呈圆形或类圆形。平扫:肿瘤呈均匀等密度者18例;肿瘤呈密度不均者7例。增强扫描:病灶呈均匀强化者4例;病灶呈不均匀强化者17例。25例GIST中,良性11例,肿块直径多5cm,边界清楚,多呈均匀强化;恶性者15例,肿块直径均5cm,边界常不清楚,多呈不均匀强化,2例出现转移灶。结论 CT检查对GIST的定位准确,对肿瘤良恶性的判断亦很有价值。     

螺旋CT对胃肠道间质瘤的诊断价值

目的分析胃肠道间质瘤(GIST)的CT表现,探讨CT对胃肠道间质瘤的诊断价值。方法回顾性分析50例经手术病理和免疫组化证实的胃肠道间质瘤的螺旋CT表现。结果肿瘤发生于胃17例、小肠11例、结直肠7例、食管6例、腹膜后5例和肠系膜4例。50例GIST中良性12例,恶性24例,交界性14例。本组CT定位准确率为100%(50/50)。CT判断良恶性准确度为76%(38/50)。结论 CT检查对临床诊断胃肠道间质瘤具有重要的术前诊断价值,但因为缺乏特异性诊断,仍需手术病理检查确诊。     

胃肠道间质瘤的CT诊断

目的 分析胃肠道间质瘤(GIST)的CT表现特点,探讨CT对该肿瘤的诊断价值.方法 回顾性分析经手术病理证实的GIST 21例,术前均行CT平扫和增强扫描.结果 肿瘤发生于胃部11例,十二指肠1例,空肠5例,回肠4例.病灶多呈圆形或类圆形.平扫:肿瘤呈均匀等密度者8例;肿块周边呈等密度,中间呈略低密度或低密度者12例;呈高、等、低混杂密度者1例.增强扫描:病灶中度或明显强化者10例;不均匀强化,其内可见多数小囊状坏死者5例;病灶中央坏死、液化,周边强化者6例.21例GIST中,良性7例,肿块直径多小于5 cm,边界清楚,多均匀强化;恶性14例,肿块直径大于5 cm,边界多不清楚,10例肿块内有坏死,5例出现转移灶.结论 CT检查对于GIST的定位准确,对肿瘤良恶性的判断亦很有价值,但CT表现无特异性,确诊仍有赖于病理学检查.     

多层螺旋CT在胃肠道间质瘤诊断中的应用

目的探讨多层螺旋CT(MSCT)对胃肠道间质瘤(GIST)的诊断价值。方法回顾性分析31例经手术病理证实的GIST的MSCT资料。结果 31例中,肿瘤位于胃部19例、小肠8例、结肠3例、肠系膜1例。病理诊断:7例良性GIST,8例交界性GIST,16例恶性GIST。主要CT表现为圆或类圆形肿块影,良性肿块边缘较清晰,恶性边界不清,部分边缘呈分叶状。平扫密度较为均匀。增强后肿瘤实质部分强化较为明显。结论 CT可作为GIST的常规检查方法,可对肿瘤进行准确定位,有助于判断GIST的性质,指导临床治疗和预后评估。     

Application of multi-slice spiral CT in diagnosis of extragastrointestinal stromal tumor

目的 探讨多层螺旋CT(MSCT)对胃肠道间质瘤(GIST)的诊断价值.方法 回顾性分析31例经手术病理证实的GIST的MSCT资料.结果 31例中,肿瘤位于胃部19例、小肠8例、结肠3例、肠系膜1例.病理诊断:7例良性GIST,8例交界性GIST,16例恶性GIST.主要CT表现为圆或类圆形肿块影,良性肿块边缘较清晰,恶性边界不清,部分边缘呈分叶状.平扫密度较为均匀.增强后肿瘤实质部分强化较为明显.结论 CT可作为GIST的常规检查方法,可对肿瘤进行准确定位,有助于判断GIST的性质,指导临床治疗和预后评估.     

肾上腺偶发瘤43例临床分析

目的 提高肾上腺偶发瘤的诊断和治疗水平。方法回顾性分析1985年至2003年5月收治的肾上腺偶发瘤43例。结果所有患者均行手术治疗,术后病理诊断：肾上腺皮质腺瘤12例,肾上腺囊肿10例,肾上腺节细胞神经瘤7例,肾上腺皮质癌4例,肾上腺转移癌3例,肾上腺髓性脂肪瘤3例,肾上腺嗜铬细胞瘤4例。结论对于肾上腺偶发瘤,均应常规行内分泌检查,CT对确诊肾上腺占位病变有较高价值。对于确诊为恶性肿瘤、功能性肿瘤及直径大于3．5cm的肿瘤,应积极采取手术治疗,应警惕偶发性嗜铬细胞瘤的潜在危险性,对非功能性、直径小于3．5cm的肿瘤可行CT随诊。     

MRI与CT在胃肠道间质瘤诊断中的影像特点及诊断价值分析

目的评价磁共振成像(MRI)与CT对胃肠道间质瘤(GIST)的诊断价值。方法回顾性分析62例GIST患者的临床资料,分析MRI与CT的影像学表现;以术后病理结果作为金标准,比较两种诊断方法的特异度、敏感度、阳性预测值及阴性预测值。结果CT共检出病灶72处。肿瘤大小直径为(2.80±0.54)cm;病灶处边界清晰占87.5%,密度均匀占56.9%,形态呈圆形或类圆形占62.5%,病灶处见钙化灶15个(20.8%)。MRI共检出病灶75处。肿瘤大小直径(2.60±0.62)cm,病灶处边界清晰占89.3%,密度均匀占65.3%,形态呈圆形或类圆形占68.0%,T1WI信号呈低信号或等信号占69.3%,T2WI信号为高信号为主的混杂信号占81.3%。MRI诊断的敏感度91.7%、特异度92.1%、阳性预测值88.0%、阴性预测值94.6%均显著高于CT的66.7%、73.7%、61.5%、77.8%,差异有统计学意义(P<0.05)。结论GIST的早期诊断与治疗是该病的关键,CT与MRI对于该病的检查均有影像特征,但MRI对GIST患者肿瘤表现特征性更加明显,并且对于恶性GIST患者MRI可以显著提高诊断敏感度与特异度,更加有利于GIST患者检出。     

胃间质瘤的多层螺旋CT影像表现分析

目的 探讨胃间质瘤的多层螺旋CT影像表现分析.方法 选取2008年2月至2011年5月胃间质瘤患者16例,回顾分析多层螺旋CT的影像表现,对病变位置、大小、形态、数量等观察指标进行总结分析.结果 本组16例患者多层螺旋CT扫描体现,肿瘤体直径<5 cm 12例,直径5～10 cm 3例,直径>10 cm 1例;瘤体呈大小不等类圆形肿块;向腔内生长5例,向腔外生长11例;平扫时肿瘤边界清楚11例,边界不清5例;病灶密度不均、内部可见斑片状低密度囊变坏死15例;增强后扫描实性病灶呈不均匀强化、囊变坏死区不增强;未见淋巴结和周围脏器转移病例;16例均经手术和病理证实;本组病例CT诊断结果全部相符.结论 多层螺旋CT在对胃间质瘤的诊断具有一定的影像特征,对胃间质瘤的临床诊断有重要意义.     

胃肠道间质瘤的多层螺旋CT诊断

目的探讨胃肠道间质瘤(GISTs)的多层螺旋CT表现及其诊断价值。方法收集经手术病理证实的GISTs23例,术前均行多层螺旋CT平扫及双期增强扫描。结果 23例中,肿瘤发生于胃12例,空、回肠7例,十二指肠2例,食管和小肠系膜各1例。良性间质瘤5例,交界性2例,恶性间质瘤16例。良性平均直径3.6cm,交界性平均直径4.4cm,恶性者平均直径6.7cm。病灶呈圆形或类圆形。平扫:呈均匀等密度7例;肿块周边呈等到密度,中央低密度区15例;混杂密度1例。增强:病灶呈明显均匀强化6例;病毒灶不均匀强化,其中可见散在囊状坏死17例。结论多层螺旋CT是目前GISTs检查的最佳选择,并能通过多方位重建(MPR)更清晰显示病灶各项特征,多层CT血管造影三维成像(3D-MSCTA)寻找肿瘤血管及其他血管变化,显著提高了GISTs的检出率和诊断准确率,对GISTs的定位和定性诊断具有重要价值。     

28例胃肠道间质瘤CT诊断分析

目的探讨胃肠道间质瘤(GIST)的CT影像特征和临床应用价值。方法分析通过手术和病理确诊的28例胃肠道间质瘤患者的CT影像材料和I期临床资料。结果显示肿瘤位于胃部14例,十二指肠6例,空肠4例,回肠1例,胃肠道外2例。28例中恶性17例,交界性6例,良性5例。CT影像资料显示为腔内外有大量肿块,直径范围约1.5～22cm,<5cm患者7例,≥5cm者21例,肿块呈类圆球形和不规则形状,密度为均匀及不均匀分布,增强后实性部分强化程度由中度到明显。3例患者瘤内出现点状钙化灶。结论胃肠道间质瘤的CT影像呈现一定特点,对临床诊断有指导意义。     

Pharmacological treatment of COVID-19: an opinion paper

The precocity and efficacy of the vaccines developed so far against COVID-19 has been the most significant and saving advance against the pandemic. The development of vaccines has not prevented, during the whole period of the pandemic, the constant search for therapeutic medicines, both among existing drugs with different indications and in the development of new drugs. The Scientific Committee of the COVID-19 of the Illustrious College of Physicians of Madrid wanted to offer an early, simplified and critical approach to these new drugs, to new developments in immunotherapy and to what has been learned from the immune response modulators already known and which have proven effective against the virus, in order to help understand the current situation.     

Efficacy of gut lavage,hemodialysis, and hemoperfusion in the therapy of paraquat or diquat intoxication

Clinical and in vitro investigations were carried out to test the efficacy of gut lavage, hemodialysis, and hemoperfusion in the treatment of poisoning with paraquat or diquat. In a patient suffering from diquat intoxication 130 times more diquat was removed by gut lavage 30 h after ingestion than was removed by complete aspiration of the gastric contents.Determination of in vitro clearances for paraquat and diquat by hemodialysis showed that, at serum concentrations of 1–2 ppm, such as are frequently encountered in poisoning in man, toxicologically relevant quantities of herbicide cannot be removed from the body. At a concentration of 20 ppm, on the other hand, hemodialysis proved to be effective, the clearance being 70 ml/min at a blood flow rate of 100 ml/min. The efficacy of hemoperfusion with coated activated charcoal was on the whole better. Especially at concentrations around 1–2 ppm, the clearance values for hemoperfusion were some 5–7 times higher than those for hemodialysis.In a patient suffering from paraquat poisoning, both hemodialysis as well as hemoperfusion were carried out. The in vitro results could be confirmed: At serum concentrations of paraquat less than 1 ppm no clearance could be obtained by hemodialysis while by hemoperfusion with activated charcoal quite high clearance values were measured and the serum level dropped down to zero.

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Zusammenfassung Klinische Untersuchungen und Laboratoriumsversuche wurden durchgeführt, um die Wirksamkeit von Darmspülung, Hämodialyse und Hämoperfusion bei Paraquat- und Deiquat-Vergiftungen zu prüfen.Bei einem Patienten wurde 30 Std nach Deiquat-Aufnahme durch Darmspülung 130mal mehr Deiquat entfernt als durch vollständige Aspiration des Mageninhaltes. In vitro-Versuche ergaben, daß bei Blutserumkonzentrationen von 1–2 ppm, die bei Vergiftungen oft gemessen werden, durch Hämodialyse keine toxikologisch relevanten Paraquat- oder Deiquat-Mengen entfernt werden können. Dagegen erwies sich die Hämodialyse bei 20 ppm und einer Blutumlaufgeschwindigkeit von 100 ml/min mit einer Clearance von 70 ml/min als wirksam. Die Hämoperfusion mit beschicheter Aktivkohle war in diesen Versuchen aber eindeutig überlegen, denn insbesondere bei Konzentrationen um 1–2 ppm waren die Clearance-Werte 5–7mal höher als bei der Hämodialyse.Die in vitro-Ergebnisse wurden bei einem Patienten mit einer Paraquat-Vergiftung bestätigt: Bei Konzentrationen unter 1 ppm war die Hämodialyse wirkungslos, während durch Hämoperfusion relativ hohe Clearance-Werte erreicht wurden, so daß der Serumspiegel rasch unter die Nachweisgrenze abfiel.

     

In vitro studies on sterically stabilized liposomes (SL) as enzyme carriers in organophosphorus (OP) antagonism

This study describes a new approach for organophosphorous (OP) antidotal treatment by encapsulating an OP hydrolyzing enzyme, OPA anhydrolase (OPAA), within sterically stabilized liposomes. The recombinant OPAA enzyme was derived from Alteromonas strain JD6. It has broad substrate specificity to a wide range of OP compounds: DFP and the nerve agents, soman and sarin. Liposomes encapsulating OPAA (SL)* were made by mechanical dispersion method. Hydrolysis of DFP by (SL)* was measured by following an increase of fluoride ion concentration using a fluoride ion selective electrode. OPAA entrapped in the carrier liposomes rapidly hydrolyze DFP, with the rate of DFP hydrolysis directly proportional to the amount of (SL)* added to the solution. Liposomal carriers containing no enzyme did not hydrolyze DFP. The reaction was linear and the rate of hydrolysis was first order in the substrate. This enzyme carrier system serves as a biodegradable protective environment for the recombinant OP-metabolizing enzyme, OPAA, resulting in prolongation of enzymatic concentration in the body. These studies suggest that the protection of OP intoxication can be strikingly enhanced by adding OPAA encapsulated within (SL)* to pralidoxime and atropine.     

Synthesis,Cytotoxicity and Antileishmanial Activity of Some N-(2-(indol-3-yl)ethyl)-7-chloroquinolin-4-amines

We report herein the condensation of 4,7-dichloroquinoline (1) with tryptamine (2) and D-tryptophan methyl ester (3) . Hydrolysis of the methyl ester adduct (5) yielded the free acid (6) . The compounds were evaluated in vitro for activity against four different species of Leishmania promastigote forms and for cytotoxic activity against Kb and Vero cells. Compound (5) showed good activity against the Leishmania species tested, while all three compounds displayed moderate activity in both Kb and Vero cells.     

Steroidal sapogenin contents in some domestic plants

In order to find out the values of the steroid resources for the future use. the compositions and contents of steroidal sapogenins from 13 domestic plants have been investigated. As a result,Dioscorea nipponica, D. quinqueloba andSmilax china were found to have large amount of diosgenin. And pennogenin inTrillium kamtschaticum andParis verticillata, yuccagenin inAllium fistulosum, hecogenin inAgave americana and neochlorogenin inSolanum nigum were appeared to be major steroidal sapogenins.     

Aquatic Insects and Trace Metals: Bioavailability,Bioaccumulation, and Toxicity

Abstract

The uptake of metals from food and water sources by insects is thought to be additive. For a given metal, the proportions taken up from water and food will depend both on the bioavailable concentration of the metal associated with each source and the mechanism and rate by which the metal enters the insect. Attempts to correlate insect trace metal concentrations with the trophic level of insects should be made with a knowledge of the feeding relationships of the individual taxa concerned. Pathways for the uptake of essential metals, such as copper and zinc, exist at the cellular level, and other nonessential metals, such as cadmium, also appear to enter via these routes. Within cells, trace metals can be bound to proteins or stored in granules. The internal distribution of metals among body tissues is very heterogeneous, and distribution patterns tend to be both metal and taxon specific. Trace metals associated with insects can be both bound on the surface of their chitinous exoskeleton and incorporated into body tissues. The quantities of trace meals accumulated by an individual reflect the net balance between the rate of metal influx from both dissolved and particulate sources and the rate of metal efflux from the organism. The toxicity of metals has been demonstrated at all levels of biological organization: cell, tissue, individual, population, and community. Much of the literature pertaining to the toxic effects of metals on aquatic insects is based on laboratory observations and, as such, it is difficult to extrapolate the data to insects in nature. The few experimental studies in nature suggest that trace metal contaminants can affect both the distribution and the abundance of aquatic insects. Insects have a largely unexploited potential as biomonitors of metal contamination in nature. A better understanding of the physico-chemical and biological mechanisms mediating trace metal bioavailability and exchange will facilitate the development of general predictive models relating trace metal concentrations in insects to those in their environment. Such models will facilitate the use of insects as contaminant biomonitors.