超声造影增强特征和定量参数鉴别甲状腺微小乳头癌的效能及与生物学行为的关系研究

本研究选取了甲状腺微小乳头癌患者68例作为研究组,甲状腺良性小结节患者65例作为对照组,探究了超声造影增强特征和定量参数在鉴别甲状腺微小乳头癌与良性小结节中的应用价值及与其生物学行为的关系.其中研究组超声造影增强特征以早期低增强或低增强为主,对照组以等增强或高增强为主,两组超声造影增强特征对比,差异有统计学意义(P＜0...     

超声弹性成像联合超声造影在鉴别原发性及转移性肝癌中的应用

为探讨超声弹性成像联合超声造影在鉴别原发性及转移性肝癌中的应用价值，选择2016年12月至2018年12月期间本院消化外科住院部收治的肝癌患者160例作为研究对象，根据病理组织学检查结果将患者分为原发组和转移组，各80例，两组进行超声弹性成像和超声造影检查，分析单项和两者联合检查对原发性及转移性肝癌的鉴别诊断效能。结果显示，原发组超声弹性成像评分（3.41±0.85）分，明显高于转移组的（1.52±0.62）分，两组比较差异具有统计学意义，P<0.05。与转移组相比较，原发组造影峰值时间明显延长，造影始增时间明显缩短，造影峰值增强速率明显降低，两组比较差异具有统计学意义（P<0.05）。两者联合检查对原发性及转移性肝癌的鉴别诊断灵敏度、特异度、阳性预测值、阴性预测值、准确度高于超声弹性成像或超声造影单项检查，漏诊率和误诊率低于超声弹性成像或超声造影单项检查，两者联合检查对原发性及转移性肝癌的鉴别诊断准确度明显高于超声造影单项检查，P<0.05。说明超声弹性成像联合超声造影有利于明显提高原发性及转移性肝癌的鉴别诊断准确度，值得临床推广应用。     

CTA成像在下肢血管闭塞病变中的应用及与血管腔内疗效的关系

本文探讨计算机体层扫描血管造影(CTA)检查在下肢血管闭塞病变中的应用价值及与血管腔内疗效的关系。选取经数字减影血管造影(DSA)确诊的93例下肢血管闭塞病变患者,采用CTA检查,分析CTA诊断病变部位结果、血管狭窄程度及与DSA诊断结果的一致性,并探讨CTA征象与患者血管腔内疗效的关系。结果显示,CTA诊断下肢血管闭塞病变部位、狭窄程度与DSA诊断结果均具有较高一致性(P<0.05);病变血管长度>1.41 cm、血管狭窄程度4级、病变血管远端CT值>62.65 Hu、钙化性斑块是下肢血管闭塞病变血管腔内治疗失败的危险因素(P<0.05)。CTA检查是诊断下肢血管闭塞病变的可靠方法,通过检查患者病变血管长度、血管狭窄程度、远端CT值及管腔内粥样斑块性质,有助于降低治疗盲目性,提高血管腔内治疗成功率。     

超声及超声造影引导下粗针活检在周围型肺部病变中的应用

探讨超声及超声造影引导下粗针活检在周围型肺部病变中的应用价值。选择158例经CT或MRI诊断为周围型肺部病变的患者作为研究对象,将其分为常规超声组及超声造影组。常规超声组在普通超声引导下进行穿刺活检,超声造影组则在普通超声的基础上行超声造影检查,然后在其引导下行经皮穿刺活检。比较超声造影组与常规超声组穿刺成功率、病灶内坏死的显示率、亚型(分类)诊断准确率、表皮生长因子受体(EGFR)阳性率及穿刺术后并发症等情况。根据病理结果,超声造影组的成功率(100%)明显高于常规超声组(90%),P<0.05。超声造影组的坏死显示率(46%)明显高于常规超声组(21%),P<0.05。超声造影组的亚型(分类)诊断准确率(96%)略高于常规超声组(94%),差异无统计学意义(P>0.05)。超声造影组的EGFR阳性率(32%)略低于常规超声组(35%),差异无统计学意义(P>0.05)。超声及超声造影引导下穿刺对于周围型肺部病变的诊断具有重要价值,超声造影对于病灶与周边组织结构的关系及病灶内部的血流情况较常规超声更具优势,可有效提高穿刺成功率。     

超声联合计算机在晚期恶性梗阻性黄疸治疗中的应用

本文探讨了常规超声、超声造影联合计算机辅助在内镜下逆行胰胆管造影术(ERCP)、经皮经肝穿刺胆道引流术(PTCD)与超声内镜引导下胆道引流术(EUS-BD)治疗晚期恶性梗阻性黄疸中的应用。选取54例晚期恶性梗阻性黄疸患者为研究对象,将其分为ERCP组、PTCD组、EUS-BD组,分析三组患者住院天数、近期并发症和肝脏功能指标等。结果显示:(1)三组患者手术后在治疗晚期恶性梗阻性黄疸效果显著(P<0.01);(2)与其他两组相比,EUS-BD组并发症和住院天数最少(P<0.05);(3)病理分析结果显示,ERCP组和EUS-BD组对导管伤害较少。总之,EUS-BD组患者采用常规超声联合计算机辅助技术,与ERCP组超声造影及PTCD组常规超声相比,更具备优势。     

人工种植牙失败原因分析

目的分析人工种植牙失败原因,探讨其预防对策。方法回顾性分析240例种植牙患者,统计其失败发生率。分析失败与性别、年龄、糖尿病、吸烟、种植部位及牙周炎的关系。结果种植牙失败主要原因为年龄、糖尿病、吸烟及牙周炎,失败率为8.75%。种植牙失败者,≥60岁的患者失败率明显高于〈60岁的患者（P〈0.05）;糖尿病与吸烟因素具有显著性差异（P〈0.01）,有糖尿病与吸烟的患者种植牙失败率分别为24.1%与16.7%;牙周炎的患者失败率明显高于无牙周炎的患者。结论年龄、糖尿病、吸烟及牙周炎与种植牙成功率密切相关,临床上应针对性加以防治。     

家兔下丘脑与腰髓间的直接联系

本文将辣根过氧化物酶(HRP)注射于7例家兔的腰6段内以后,追踪了下丘脑中的标记.除观察了逆行标记细胞的分布外,还发现了明确的顺行标记纤维及终枝. 下丘脑-脊髓投射细胞主要分布于注射侧的下丘脑后区、背侧区、外侧区及室旁核中;穹窿周围核中也有一些;少见或偶见于结节区、乳头体上核及视上核之背侧方. 脊髓-下丘脑投射主要终止于对侧,经两条入路:(1)背侧纵束,分布于下丘脑后区,可能还至乳头体上核;(2)在乳头体丘脑束的腹侧方由外向内侧横行,止于下丘脑内、外侧区的背侧部,少量散入腹侧区。     

MSCT联合ERCP对十二指肠憩室合并胆结石患者术后感染的影响

探究基于多层螺旋CT(MSCT)、内镜逆行胰胆管造影术(ERCP)观察对十二指肠憩室合并胆结石患者术后感染控制的影响。选取210例十二指肠憩室合并胆结石患者,随机分为研究组和对照组,各105例。对照组行ERCP内镜取石术,研究组行基于MSCT、ERCP的内镜取石术。结果显示,研究组ERCP插管成功率高于对照组,手术时间、鼻胆管引流时间及术后住院时间短于对照组(P<0.05);两组术后1 d、3 d血清C反应蛋白(CRP)、肿瘤坏死因子-α(TNF-α)、血糖(Glu)、皮质醇(Cor)水平均高于术前,但研究组均低于对照组(P<0.05);两组术后1 d、3 d血清CD3⁺、CD4⁺水平均低于术前,但研究组均高于对照组(P<0.05),两组术后1 d血清CD8⁺水平均低于术前(P<0.05);研究组切口感染、胆道感染发生率,以及术后6个月、1年复发率均低于对照组(P<0.05)。可见,基于MSCT、ERCP观察行内镜下取石术,能降低十二指肠憩室合并胆结石患者术后感染发生率,有效减少术后复发。     

环己醇氧化制备己二酸实验工艺改进探究

为了找到己二酸制备实验效果不佳的原因，从4个方面进行了探讨：环己醇最佳滴加速度的确定、反应温度随时间的变化规律、凝聚时间对产品品质的影响及浓缩液的适宜体积。通过实验探究，找到了学生实验失败的主要原因，改进了实验装置，并确定了实验最佳工艺条件：环己醇的滴速20 s/滴左右，凝聚时间8 min，浓缩液的体积约20 mL。改进后的实验成功率达到90%以上，产品品质良好。     

药物流产后宫内残留物的腹部超声检测及其对清宫术时机的指导作用

本文对药物流产后宫内残留物的腹部超声检测及其对清宫术时机的指导作用进行了探讨。研究对象为2017年4月~2018年10月我院妇科收治的164例药物流产后宫内组织残留患者,所有患者均行经腹彩色多普勒超声检查,观察宫腔内异常回声团和宫内血流信号及频谱,并记录患者治疗情况和病理结果。依据患者保守治疗成功或转归清宫术分为成功组和转归组,采用多因素Logistic回归方程分析对保守治疗失败转归清宫术有影响的因素。结果显示,164例患者中,79例(48.17%)患者超声检查显示存在滋养血流,其中47例(59.49%)患者采取了清宫术治疗,其余32例(40.51%)患者保守治疗失败转归清宫术治疗;85例(51.83%)患者超声检查显示无滋养血流,其中73例(85.88%)采取保守治疗成功,其余12例(14.12%)患者保守治疗失败转归清宫术;成功组(n=73)和转归组(n=44)患者在就诊时阴道出血时间、阴道出血持续时间、流产次数、宫内残留物大小、滋养血流信号检出率等方面的比较,差异均具有统计学意义(P<0.05);多因素Logistic回归方程分析结果显示,就诊时阴道出血时间、残留物大小、流产次数、超声检查存在滋养血流均为保守治疗转归清宫术的独立影响因素(P<0.05)。本文结果证实,腹部超声检测显示宫腔内异常回声团块存在滋养血流信号,可作为药物流产不全患者行清宫术治疗的手术指征,有利于改善患者预后。     

外伤性膝关节隐性骨折的核磁共振成像表现及其诊断价值分析

为分析外伤性膝关节隐性骨折的核磁共振成像表现及其诊断价值,本次研究回顾性分析我院2017年1月~2018年12月收治的55例外伤性膝关节隐性骨折患者临床资料,分别实施核磁共振成像检查以及多层螺旋CT检查,然后以手术结果为参照,分析核磁共振成像对外伤性膝关节隐性骨折的诊断价值及具体的影像表现。经手术证实,55例外伤性膝关节隐性骨折患者中隐性骨皮质下骨折34例、骨皮质骨折14例、骨软骨骨折7例,核磁共振成像符合率高于多层螺旋CT,差异有统计学意义(P<0.05);两种影像学检查手段敏感度、特异度、准确度相比较,核磁共振成像高于多层螺旋CT,差异有统计学意义(P<0.05);外伤性膝关节隐性骨折核磁共振成像表现如下:隐性骨皮质下骨折存在大范围的地图样、网格状或线状信号区,边界模糊但骨关节面完整;骨皮质骨折呈低信号带中断,与骨髓高信号存在强烈对比;骨软骨骨折呈多层次或者是连续性中断。说明外伤性膝关节隐性骨折核磁共振成像表现具有多样性特点,仔细分析不难鉴别,可作为优选诊断手段推广使用。     

Scanning electron microscopic structure of the lingual papillae of the common opossum (Didelphis marsupialis).

The mammalian tongue has evolved for specialized functions in different species. The structure of its papillae tells about the animal's diet, habit, and taxonomy. The opossum has four kinds of lingual papillae (filiform, conical, fungiform, vallate). Scanning electron microscopy of the external features, connective tissue cores, and corrosion casts of the microvasculature show the filiform papillae have a spearhead-like main process and spiny accessory processes around the apical part of the main process. The shape and number of both processes depend on their position on the tongue. On the apex, the main processes have shovel-like capillary networks and the accessory processes have small conical networks. On the lingual radix, the processes have small capillary loops. In the patch region, conical papillae have capillaries arranged as a full sail curving posteriorly. The fungiform papillae are scattered among the filiform papillae and have capillary baskets beneath each taste bud. Giant fungiform papillae on the tongue tip are three to four times larger than the ones on the lingual body. Capillaries of giant papillae form a fan-shaped network. The opossum has three vallate papillae arranged in a triangle. Their tops have secondary capillary loops but not their lateral surfaces. Mucosal folds on the posterolateral border have irregular, fingerlike projections with cylindrical capillary networks. These findings and the structure of the rest of the masticatory apparatus suggest the lingual papillae of opossum have kept their ancestral carnivorous features but also developed the herbivore characteristics of other marsupials.     

A transportable neutron radiography system

A transportable neutron radiography system, incorporating a 50 mg ²⁵²Cf source, has been simulated using the MCNPX code. The materials considered were compatible with the European Union Directive on ‘Restriction of Hazardous Substances’ (RoHS) 2002/95/EC, hence excluding the use of cadmium and lead. The design was optimized with respect to neutron moderation, shielding and collimation. High density polyethylene was chosen as the material for moderator and also shielding, which was further enhanced with layers of bismuth and borated polyethylene. Variable values for the collimator ratio were calculated. With suitable aperture and collimator design it was possible to optimize the neutron radiography parameters. Beam filters also were treated in order to improve the results. The proposed system has been considered with a wide range of radiography parameters, which are comparable with neutron radiography facilities from low power reactors.     

MALDI Mass Spectrometry Imaging for the Distinction of Adenocarcinomas of the Pancreas and Biliary Tree

Pancreatic ductal adenocarcinoma and cholangiocarcinoma constitute two aggressive tumor types that originate from the epithelial lining of the excretory ducts of the pancreatobiliary tract. Given their close histomorphological resemblance, a correct diagnosis can be challenging and almost impossible without clinical information. In this study, we investigated whether mass spectrometric peptide features could be employed to distinguish pancreatic ductal adenocarcinoma from cholangiocarcinoma. Three tissue microarrays of formalin-fixed and paraffin-embedded material (FFPE) comprising 41 cases of pancreatic ductal adenocarcinoma and 41 cases of cholangiocarcinoma were analyzed by matrix-assisted laser desorption/ionization mass spectrometry imaging (MALDI-MSI). The derived peptide features and respective intensities were used to build different supervised classification algorithms: gradient boosting (GB), support vector machine (SVM), and k-nearest neighbors (KNN). On a pixel-by-pixel level, a classification accuracy of up to 95% could be achieved. The tentative identification of discriminative tryptic peptide signatures revealed proteins that are involved in the epigenetic regulation of the genome and tumor microenvironment. Despite their histomorphological similarities, mass spectrometry imaging represents an efficient and reliable approach for the distinction of PDAC from CC, offering a promising complementary or alternative approach to the existing tools used in diagnostics such as immunohistochemistry.     

Optimisation of a matrix solid-phase dispersion method for the determination of organophosphate compounds in dust samples

A fast and inexpensive sample preparation procedure based on the matrix solid-phase dispersion (MSPD) technique is proposed for the isolation of several organophosphate esters (mainly employed as flame retardants and plasticizers) from indoor dust samples. Extraction and clean-up were carried out in a single step and target compounds were determined by gas chromatography (GC) with nitrogen-phosphorus detection (NPD). The main parameters affecting extraction yield and selectivity, such as type and amount of dispersant material, clean-up co-sorbent and extraction solvent, were evaluated and optimised. Under final conditions, 0.5 g of dust were dispersed with equal amounts of anhydrous sodium sulphate and Florisil, and loaded on the top of a polypropylene cartridge containing 0.5 g of alumina. The dispersed sample was washed with 2 mL of n-hexane to remove the least polar interferences and analytes were eluted with 3 mL of acetone. Recoveries of the proposed method for spiked samples ranged from 80 to 116%, and the day-to-day variability remained between 5 and 10%. Data on levels of organophosphate species in dust from private houses and vehicle cabins are provided. In both cases, the lowest concentrations corresponded to the short chain, non-chlorinated, alkyl organophosphates, whereas mean values above 1 μg g⁻¹ were measured for the rest of analytes.     

MISCHKLONE U.V.-INDUZIERTER MUTANTEN BEIM PHAGEN KAPPA

Abstract— Clear-plaque mutations of phage k of Serratia are induced by extracellular u.v.-irradiation in a 2–hit process. The 2–hit-nature cannot be due to induction of one hit in each of the two DNA-strands since replating the contents of 97 wildtype plaques of u.v.-survivors (u.v.-dose 4.5 min) revealed only 1 case of heterozygosity; at least 20 cases would have been expected if phage with 1–hit-mutations formed phages looking like wildtype. On the other hand, only 1 case of heterozygosity was observed among replatings of 94 c -mutants induced by the u.v.-dose 4.5 min (survival 10^-3); most of the plaques contained pure c -type. The pure c -mutant clones are very probably due to 'recessive' lethal lesions in the nonpremutated DNA-strand. This is indicated by the dose dependence of the frequency of heterozygotes; at a dose of 3 min u.v. (survival 1.2 × 10^--²) 9 heterozygotes were observed among 95 mutants tested. From these numbers the rate of induction by u.v. of the recessive lesions's can be calculated. The data at the higher dose are in satisfactory agreement with the calculated rate. Also other types of plaque mutations (e, t, b ) showed heterozygosity. Two cases of abnormal heterozygosity were observed; one contained 2 stable mutant types ( c and b ), another one wildtype, c -tm and l -type.     

Dissolution of metallic platinum as water soluble species by naturally occurring complexing agents

Platinum is released into the environment as a result of surface abrasion from automobile catalysts during operation. Previous investigations showed that this finely dispersed metallic platinum is dissolved in organic matrices, e.g. a humic soil to a significantly high degree, resulting in possibly bioavailable Pt species. In this work several natural complexing agents (adenosine, ADP, ATP, L-His, humic acid fraction, L-Met, pyrophosphate, and triphosphate) were treated with metallic platinum (as Pt black and as a Pt(0) containing tunnel dust) for 3–60 d. Some of the compounds used dissolved Pt(0) to a recognizable degree, whereas others were in the range of the aqueous blanks. Comparison of Pt black with a natural dust sample showed that L-methionine had in both cases the greatest effect after 60 d. Generally more Pt(0) was dissolved in the dust sample (finer dispersion and smaller particle size) than in the Pt-black used. By carrying out the experiment under natural conditions instead of in pure oxygen-, the amounts of dissolved platinum are about one order of magnitude lower.On leave from Liaoning University, Department of Chemistry, 110036 Shenyang, PR China     

Study of normal colorectal tissue by FT-Raman spectroscopy

FT-Raman spectroscopy was employed to study normal human colorectal tissues in vitro with the aim of evaluating the spectral differences of the complex colon mucous in order to establish a characteristic Raman spectrum. The samples were collected from 39 patients, providing 144 spectra for the statistical analysis. The results enable one to estabilish three well-defined spectroscopic groups of non-altered coloretal tissues that were consistently checked by statistical (clustering) and biological (histopathology) analyses: group 1 is represented by samples with the presence of epithelial layer, connective tissue papillae, and smooth muscle tissue; group 2 comprises tissues with epithelial layer and connective tissue papillae; group 3 presented mostly fatty and slack conjunctive tissue. The study reveals the existence of an intrinsic spectral variability for each patient that must be considered when sampling tissues fragments to build a spectral database. This is the first step for future studies and applications of Raman spectroscopy to optical biopsy and diagnosis of colorectal cancer.     

Self-organization and growth of dust structures in a glow discharge

Ordered structures of macroparticles in a dc glow discharge in inert gases were systematically studied. A special automated system and software were developed for data acquisition and processing. It was found that the shape and volume of a dust cloud depend on discharge conditions and the number of particle injections, whereas the average interparticle distance does not depend on the number of injections. Despite of a low concentration of macroparticles, their effect on the electric and optical parameters of a plasma was noticeable in some cases. These results demonstrate that dust structures in a plasma are a special type of matter and currently available theoretical models cannot adequately describe the majority of the observed phenomena.     

Intraoperative chemiluminometric assay for simplified localization of parathyroid adenomas during surgery for primary hyperparathyroidism

Hyperparathyroidism is no longer considered an uncommon endocrinopathy. Between 1994 and 2002, 138 patients underwent neck exploration for primary hyperparathyroidism at the Department for Surgery in the University Hospital of Dresden. Common reasons for operation failure are usually hyperplasia or remnant parathyroid tissue, inadequate parathyroidectomy at initial operation or the occurrence of abnormal hyperfunctioning supernumerary glands. To reduce the operation time, as well as the failure rate that accompanies the incomplete excision of hypersecreting parathyroid tissue, we perform an intraoperative monitoring of parathyroid hormone with an immunochemiluminometric assay (Nichols Advantagetrade mark Intact PTH). With modification of this assay, it was possible to perform the assay in the operating theatre and to attain the hormone values within 10 min. In all cases of successful operation with excision of the adenomatous parathyroid gland the PTH values declined to under 20 percent of the initial intraoperative PTH values. Our results declare the intraoperative parathyroid hormone monitoring as a cost-effective method to control the effect of surgical treatment.