双源CT多定量参数对胃癌的诊断价值及与HER2的相关性

目的:探讨门脉期双源CT多个定量参数与胃腺癌病理分化程度及HER2的相关性。方法: 回顾性分析2018年7月至2019年4月间于陕西省人民医院行双源CT双能量扫描的48例经胃镜活检(21例)或手术病理证实（27例）的胃腺癌及30例正常胃的影像学资料,其中27例HER2指标明确,通过西门子第二代双源CT扫描获得静脉期双能量图像,利用syngo.via软件获得曲线斜率、门脉期碘浓度、标准化碘浓度;将患者分为胃腺癌与正常胃壁组,高、中、低分化胃腺癌组,HER2阳性组（+,++,+++）与HER2阴性组（-）。统计学方法采用Kappa一致性检验、ROC曲线法、两独立样本t检验及方差分析。结果:活检与术后病理结果具有较强的一致性（Kappa系数为0.701）,两者无明显差异;胃腺癌与正常胃壁两组间能谱曲线斜率（1.35±0.24、2.19±0.71）及标准化碘浓度（0.31±0.079、0.54±0.157）均具有统计学意义（P<0.05）,曲线下面积分别为0.992、0.919;低分化、中分化及高分化胃腺癌能谱曲线斜率值（3.07±0.67,2.63±0.57,2.01±0.39）组间及组内差异均具有统计学意义（P<0.05）,低分化、中分化及高分化胃腺癌门脉期标准化碘浓度(0.60±0.167,0.52±0.089,0.36±0.039)组间差异具有统计学意义（P<0.05）,中分化组与低分化组差异无统计学意义（P>0.05）,高分化组与中、低分化组均具有统计学差异（P<0.05）。HER2阳性组与阴性组的能谱曲线斜率及标准化碘浓度值无统计学差异（P>0.05）。结论:能谱曲线斜率及门脉期标准化碘浓度值有助于对胃腺癌进行诊断并推测病理分化程度;双源CT定量参数与免疫组化指标HER2无相关性。     

Evaluation on the Performance of Hydraulic Bitumen Binders under High and Low Temperatures for Pumped Storage Power Station Projects

The high and low-temperature performance of five hydraulic bitumen binders was evaluated using the dynamic shear rheometer (DSR) test, infrared spectrum test and direct tensile (DT) test. These hydraulic bitumen binders were respectively applied for several pumped storage power stations (PSPS) projects that were constructed or under construction. In order to relate the bitumen performance to the mixture performance, the slope flow test, three-point bending test and thermal stress restrained specimen test were carried out on hydraulic asphalt mixtures. The test results indicated the DSR rheological master curves can well distinguish the difference of each bitumen binder as well as the effect of polymer modification. Phase angle master curves, black diagrams and infrared spectra all indicated that several penetration-grade hydraulic bitumen binders were not virgin bitumen binders but were modified with relatively lower SBS polymer content when compared with traditional SBS-modified bitumen. When selecting the commonly used Karamay SG70 hydraulic bitumen as a reference, the normal SBS-modified bitumen was superior to other bitumen in terms of low- and high-temperature performance. Several slightly SBS-modified bitumen binders did not always show consistent results, which indicated that slightly modified bitumen may not really have the desired performance as expected. Therefore, SBS-modified bitumen will be more promising when dealing with extremely low or high temperatures. Bitumen performance was well compared with the mixture performance by using the bitumen creep, relaxation and tensile failure strain corresponding to the asphalt concrete slope flow, the maximum bending strain and the failure temperature, respectively. Compared with the traditional penetration, softening point and ductility test, it indicated that the DSR rheological test, creep test, direct tensile test and stress relaxation test can be used as more powerful tools for the characterization and optimization of hydraulic bitumen binders.     

促排卵后持续性异位妊娠2例的护理体会

<正>持续性异位妊娠(persistent ectopic pregnancy,PEP)是指输卵管妊娠术后HCG水平下降缓慢或每72h下降20%(3周血HCG仍未转阴)或降后又升或不降反升,伴或不伴附件包块和腹腔内出血者,少数患者有下腹隐痛或少许阴道流血。随着异位妊娠发生率逐年上升且渐趋向年轻化,行腹腔镜下输卵管保守手术患者增多,其最主要并发症PEP,发生率为5%~10%[1],是异位     

Postoperative spino-pelvic stereoradiography to predict adjacent segment disease

PurposeThe purpose of this study was to identify sagittal spinopelvic parameters predictive of adjacent segment disease (ASD) on postoperative whole spine weight-bearing stereoradiography.Materials and methodsA total of 84 patients with previous spinal fusion surgery and documented radiological follow-up with early weight-bearing postoperative whole spine stereoradiography (EOS® Imaging System) were retrospectively included. A pathological group of 42 patients (9 men, 33 women; mean age, 63.1 ± 11.5 [SD] years) who developed documented ASD (mean follow-up, 76.75 months; range: 31.5–158.5 months) was compared with a control group of 42 asymptomatic patients (7 men, 35 women; mean age, 60.9 ± 11.8 [SD] years) (mean follow-up, 115 months; range: 60–197 months) based on sagittal balance evaluation and routinely used spino-pelvic parameters. Comparisons were made using uni- and multivariate analyses.ResultsAt univariate analysis, patients with ASD had an anteriorly displaced sagittal vertical axis (CAM plumb line) and an inadequate lumbar lordosis (LL) in reference to pelvic incidence (PI) compared to controls. They also had higher C7 slope and C2-C7 offset. At multivariate analysis, C2-C7 offset (OR = 1.152; 95% CI: 1.056–1.256; P = 0.001) and a lack of LL (OR = 5.063; 95% CI: 1.139–22.498; P = 0.033) were significantly associated with ASD.ConclusionAnterior cervical imbalance, reflected by an increase in C2-C7 offset and insufficient restoration of LL are postoperative predictive factors of ASD on stereoradiography.     

Sensitivity of CO2 washout to changes in acinar structure in a single-path model of lung airways

A numerical solution of the convection-diffusion equation with an alveolar source term in a single-path model (SPM) of the lung airways simulates steady state CO₂ washout. The SPM is used to examine the effects of independent changes in physiologic and acinar structure parameters on the slope and height of Phase III of the single-breath CO₂ washout curve. The parameters investigated include tidal volume, breathing frequency, total cardiac output, pulmonary arterial CO₂ tension, functional residual capacity, pulmonary bloodflow distribution, alveolar volume, total acinar airway cross sectional area, and gas-phase molecular diffusivity. Reduced tidal volume causes significant steepening of Phase III, which agrees well with experimental data. Simulations with a fixed frequency and tidal volume show that changes in blood-flow distribution, model airway cross section, and gas diffusivity strongly affect the slope of Phase III while changes in cardiac output and in pulmonary arterial CO₂ tension strongly affect the height of Phase III. The paper also discusses differing explanations for the slope of Phase III, including sequential emptying, stratified inhomogeneity, and the issue of asymmetry, in the context of the SPM.     

蒲黄及其提取物对花生四烯酸诱导血小板聚集功能的影响

蒲黄及提取物总黄酮、有机酸、多糖对花生四烯酸诱导兔体内外血小板聚集功能具有明显的抑制作用,抑制最大聚集%的作用强度依次为:总黄酮>多糖>煎液>有机酸;抑制聚集坡度的作用强度为:总黄酮>煎液>多糖>有机酸;说明黄酮类物质可能是蒲黄抗血小板聚集的主要有效成分,同时表明这些药物对血小板最大聚集%和坡度的作用是有差别的。     

The Relationship between Resistance Exercise Performance and Ventilatory Efficiency after Beetroot Juice Intake in Well-Trained Athletes

The assessment of ventilatory efficiency is critical to understanding the matching of ventilation (VE) and perfusion in the lungs during exercise. This study aimed to establish a causal physiological relationship between ventilatory efficiency and resistance exercise performance after beetroot juice (BJ) intake. Eleven well-trained males performed a resistance exercise test after drinking 140 mL of BJ (~12.8 mmol NO₃⁻) or a placebo (PL). Ventilatory efficiency was assessed by the VE•VCO₂⁻¹ slope, the oxygen uptake efficiency slope and the partial pressure of end-tidal carbon dioxide (PetCO₂). The two experimental conditions were controlled using a randomized, double-blind crossover design. The resistance exercise test involved repeating the same routine twice, which consisted of wall ball shots plus a full squat (FS) with a 3 min rest or without a rest between the two exercises. A higher weight lifted was detected in the FS exercise after BJ intake compared with the PL during the first routine (p = 0.004). BJ improved the VE•VCO₂⁻¹ slope and the PetCO₂ during the FS exercise in the first routine and at rest (p < 0.05). BJ intake improved the VE•VCO₂⁻¹ slope and the PetCO₂ coinciding with the resistance exercise performance. The ergogenic effect of BJ could be induced under aerobic conditions at rest.     

The Change in Posterior Tibial Slope After Cementless Unicondylar Knee Arthroplasty

BackgroundThe posterior tibial slope (PTS) is an important factor in patients undergoing unicondylar knee arthroplasty. It is an area subjected to high shear and compressive forces. Our objective is to investigate the changes taking place on the tibial slope of cementless unicondylar knee arthroplasties and define its relationship with functional scores.MethodsPatients undergoing a cementless unicondylar knee arthroplasty between January 2011 and July 2019 were selected. Exclusion criteria were lack of at least 1 year of follow up, loss to follow-up for any reason, and revision of a metallic component. Overall, 161 cases were included. Patients were analyzed using standard radiographs for changes in PTS, coronal positioning of the implant, and overhanging. Function was analyzed using Oxford Knee Score, Tegner Activity Scale, and Knee Society Score. Changes of the PTS were analyzed for statistical significance and for correlations with all the other variables.ResultsAll postoperative functional scores showed significant improvement (P < .05). Compared to the early postoperative values, increases of ≤5° were detected in 79% of all patients. The greater amount of slope change occurred during the first 6 months postoperatively. Statistical analysis revealed no significant relationship with functional scores of the knee, age, body mass index, overhanging, and coronal alignment of the tibial component.ConclusionThis study showed that, with time, minimal changes take place in the PTS of cementless unicondylar knee arthroplasty. The change mostly takes place during the first 6 months. These changes do not affect functional scores.     

Antagonist inhibition curves and the measurement of dissociation constants

1. Experiments carried out on guinea-pig isolated ileum with carbachol as agonist and diphenyl- acetoxyethyl- dimethyl-ethyl- ammonium (DADMEA) bromide as antagonist gave results which fit the theoretical relation between fractional inhibition (Q) of the effects of an agonist ([A]) and the concentration of a competitive antagonist ([B]): this also involves the Hill coefficient (logistic slope factor, P) for the agonist concentration-response curve and the degree of agonist stimulation, [A]/[A]₅₀, where [A]₅₀ produces a half-maximum response.
2. Values of IC₅₀ and an exponent, P′, can be obtained by fitting Q to [B] using a logistic approximation to the relation. Both P′ and IC₅₀ should be greater with higher agonist stimulation but the increase in P′ may be masked by errors in extreme values of Q. Estimates of IC₅₀, however, invariably increased with higher agonist stimulation but with a steep concentration-response curve (P>1) and low agonist stimulation ([A]/[A]₅₀ <1), IC₅₀ can be less than K_D.
3. K_D was calculated from the results in three ways: (i) by a least-squares fit of Q to [B] using the values of P and [A]/[A]₅₀ calculated from the control concentration-response curve; (ii) from the value of IC₅₀ for each line and the values of P and [A]/[A]₅₀ and (iii) by using the agonist concentration-response curve to calculate the dose-ratio and estimate of K_D for each response in the presence of the antagonist. The methods gave similar results (nM: 11 experiments), 12.4±1.1 (i), 11.7±0.9 (ii), 14.8±1.6 (iii) but there are advantages in using methods (i) or (ii) rather than (iii).
4. The method by which K_D is calculated is less important than the experimental design: the plan used in this work, with alternative small and large responses from the tissue, is very suitable for estimating K_D with low concentrations of antagonists and small dose-ratios. Although it is not a sensitive test for competitive behaviour because only a small range of concentrations of antagonist is tested, the estimate of affinity should be free from complications involved in the use of higher concentrations of antagonist (and agonist) and the nature of the antagonism can always be checked by doing further experiments in the presence of a known competitive antagonist.