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目的 建立纤溶酶反相高效液相色谱纯度测定方法。方法 采用SHISEIDO CAPCELL PAK C18 SG300(250 mm×4.6 mm,5 μm),以0.1%三氟乙酸溶液-乙腈(95:5)为流动相A,以0.08%三氟乙酸溶液-乙腈(20:80)为流动相B,进行梯度洗脱,体积流量为0.7 mL·min-1,检测波长280 nm,柱温40℃。参照2020年版《中国药典》四部9101药品质量标准分析方法验证指导原则进行专属性、检测限、耐用性考察。应用所建立的方法和分子排阻色谱法对3批样品纯度进行检测。结果 建立的反相色谱法专属性强,检测限为0.01%,耐用性强。对3批样品进行检测,质量分数在93.5%~96.9%,结果准确。结论 建立反相色谱法测定纤溶酶纯度,分辨率更高、重现性更好,可进行更好的质量控制。 相似文献
3.
《Cancer radiothérapie》2022,26(4):611-615
In order to provide more convenient irradiation regimens for patient comfort, radiation facility organization and health expenses, new hypofractionated protocols have been evaluated. Moderately (dose/fraction: 2.3 to 3 Gy), then ultra (dose/fraction: 5.2 to 6.1 Gy) hypofractionated irradiations were first validated. The current question is: is it possible to go forward using extreme hypofractionated regimens (EHR) based on 1 to 3 fractions. Different irradiation techniques are under investigation. However, brachytherapy remains the smartest way to deliver a high dose in a small volume. We report prospective and retrospective study results which evaluated EHR for breast and prostate brachytherapy. While oncological outcome and toxicity profile appear extremely encouraging for low-risk breast cancer after a 1 to 4 fractions (6.25 to 20 Gy/fraction), the use of a single fraction of 19 to 23 Gy appears debatable for prostate cancer. Brachytherapy represents an emblematic example of EHR but longer follow-up and more mature results are awaited in order to specify the right indications and refine the EQD2 calculation method including new biological and technical factors. 相似文献
4.
In forensic medicine, although various alcohols have been reported as indicators of decomposition in collected blood, no studies have examined short-chain fatty acids as indicators. In this study, the blood n-butyric acid concentration was quantified, and the association between n-butyric acid and decomposition was investigated to determine whether the detection of n-butyric acid could be a new indicator of decomposition. Among the forensic autopsies performed from 2016 to 2018 in our laboratory, the cases were divided into decomposed (n = 20) and non-decomposed (n = 20) groups based on macroscopic findings. Blood samples collected at the time of autopsy were derivatized with 3-nitrophenylhydrazine hydrochloride after solid-phase extraction. The n-butyric acid concentration was measured using liquid chromatography–tandem mass spectrometry. In addition, ethanol and n-propanol were measured using a gas chromatography-flame ionization detector. There was a significant difference (p < 0.01) in the concentrations of n-butyric acid between the decomposed and non-decomposed groups (0.343 ± 0.259 [0.030–0.973] and 0.003 ± 0.002 [0.001–0.007] mg/mL, respectively). In the decomposed group, n-butyric acid was detected at high concentrations, even in cases where n-propanol was low. These results suggest that n-butyric acid is more likely to be an indicator of blood decomposition than n-propanol. 相似文献
5.
目的 评价美国国家电器制造协会(National Electrical Manufactures Association, NEMA)最新标准(NU 2-2018)在正电子发射型计算机断层显像/电子计算机断层显像(positron emission tomography/computed tomography, PET/CT)设备性能检测中的作用。 方法 依据最新的NEMA NU 2-2018标准,检测西门子Biograph Vision PET/CT的空间分辨率、灵敏度、散射分数、计数丢失、随机符合、飞行时间分辨率、计数丢失率和随机符合校正精度、图像质量、衰减和散射校正精度及PET与CT配准精度指标。 结果 距视野中心1 cm处横向和轴向空间分辨率分别为3.75 mm和3.76 mm;在视野中心和轴向10 cm处的灵敏度分别为16.83 kcps/MBq和16.67 kcps/MBq;放射性浓度为27.37 kBq/mL时,最大等效噪声计数率为258.26 kcps,散射分数为38.58%;系统时间分辨率为209.82 ps;图像质量模型的对比度恢复系数范围为88.9%~96.2%,背景变异系数范围为2.05%~6.80%,平均肺插件残余误差为2.43%;计数丢失和随机符合校正最大误差为3.9%;距离床板末端 5 cm 和 100 cm处,在距视野中心Y轴1 cm处,PET和CT的配准精度分别为0.46 mm和1.07 mm,在距视野中心X轴20 cm处,PET和CT的配准精度分别为1.06 mm和1.45 mm,在距视野中心Y轴20 cm处PET和CT的配准精度分别为0.85 mm和1.15 mm。 结论 NEMA NU 2-2018标准检测条件更加接近临床,能更好地反映PET/CT设备的系统性能。 相似文献
6.
目的探讨乙肝相关性肝癌临床病理学特征与溶血磷脂酸(LPA)和高敏C反应蛋白(hs-CRP)表达的相关性。方法选取2019年1月至2020年1月间河南省驻马店市中心医院收治的198例乙肝相关性肝癌患者作为乙肝组,198例酒精相关性肝癌患者作为酒精组。两组患者都进行血清hs-CRP和LPA表达检测,调查患者的病理学特征并进行相关性分析。结果乙肝组患者血清hs-CRP和LPA含量均高于酒精组,差异均有统计学意义(均P <0.05)。两组患者血清ALP、AFP、ALT、AST和GGT含量比较,差异均无统计学意义(P> 0.05)。乙肝组不同临床分期和组织学分化患者的血清hs-CRP和LPA含量比较,差异均有统计学意义(均P <0.05)。乙肝组患者的临床分期和组织学分化与血清hs-CRP和LPA表达均存在相关性,差异均有统计学意义(均P <0.05)。患者的临床分期和组织学分化均为影响hs-CRP和LPA表达的重要因素,差异均有统计学意义(均P <0.05)。结论相对于酒精相关性肝癌,乙肝相关性肝癌的血清hs-CRP和LPA呈现高表达,与患者的临床病理学特征存在相关性。 相似文献
7.
Breast implant associated anaplastic large cell lymphoma (BIA-ALCL) is an emergent rare T cell non-Hodgkin lymphoma arising in association with a breast implant, particularly textured ones. Recent guidelines list cytopathological examination as the first essential step for diagnosis, routinely followed by CD30 immunohistochemistry (IHC) and flow cytometry (FC) for a T cell clone. The majority of BIA-ALCL literature regarding cytopathological evaluation describes morphology based on various preparation methods limited to cytospins and smears with the exception of at least one case report detailing cytomorphological and IHC findings on ThinPrep. This case report details initial diagnosis of BIA-ALCL rendered with CytoLyt prepared ThinPrep and cell block, including the specific antibodies used for IHC. The ThinPrep slide showed numerous singly dispersed large, atypical cells with abundant cytoplasm containing irregular nuclei with dispersed chromatin and prominent nucleoli in a background of macrophages, inflammatory cells and granular debris. TIA-1 and CD30 along with other T-cell markers, including specific antibodies, remains immunoreactive in tissue collected in CytoLyt solution. Cell size reduction, artifactual lymphoid cell aggregation and prominent nucleoli in benign and reactive conditions are among other ThinPrep cellular alterations pathologists should bear in mind. 相似文献
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目的评价由丹娜(天津)生物科技股份有限公司生产的隐球菌荚膜多糖检测试剂盒(胶体金法,考核试剂)的检测性能。方法选取隐球菌和隐球菌近缘菌及肺部感染常见菌种共28属100株菌作为研究对象,配制0.5麦氏浊度单位(0.5 M)菌液检测试剂的特异性,0.5 M阳性的菌株以10倍倍比稀释液作为灵敏度检测菌液,以2 M和4 M浓度菌液作为钩状效应检测菌液,并以美国Immuno Mycologics公司生产的隐球菌抗原检测(胶体金免疫层析法)试剂盒作为对比试剂,比较两家试剂的一致性。结果31株隐球菌属菌株中,考核试剂检测出阳性25株(新型隐球菌和格特隐球菌均为阳性),阴性6株(维多利亚隐球菌、C.dimennae和大隐球菌);16株毛孢子菌属菌株中,检测出阳性12株,阴性4株;1株Cutaneotrichosporon curvatum检测结果为阳性;52株其他菌株的检测结果均为阴性;灵敏度实验结果显示考核试剂隐球菌最低检出限为1.0×102 CFU/mL;2 M和4 M浓度菌液均未出现钩状效应。结论考核试剂隐球菌荚膜多糖检测试剂盒(胶体金法)检测隐球菌属的灵敏度高于比对试剂;特异性方面存在一定的属内和属外交叉反应,但与对比试剂的检测结果高度一致;考核试剂与比对试剂均无钩状效应产生。 相似文献
10.
《Clinical neurophysiology》2021,132(9):2003-2011
ObjectiveA large N20 and P25 of the median nerve somatosensory evoked potential (SEP) predicts short survival in amyotrophic lateral sclerosis (ALS). We investigated whether high frequency oscillations (HFOs) over N20 are enlarged and associated with survival in ALS.MethodsA total of 145 patients with ALS and 57 healthy subjects were studied. We recorded the median nerve SEP and measured the onset-to-peak amplitude of N20 (N20o-p), and peak-to-peak amplitude between N20 and P25 (N20p-P25p). We obtained early and late HFO potentials by filtering SEP between 500 and 1 kHz, and measured the peak-to-peak amplitude. We followed up patients until endpoints (death or tracheostomy) and analyzed the relationship between SEP or HFO amplitudes and survival using a Cox analysis.ResultsPatients showed larger N20o-p, N20p-P25p, and early and late HFO amplitudes than the control values. N20p-P25p was associated with survival periods (p = 0.0004), while early and late HFO amplitudes showed no significant association with survival (p = 0.4307, and p = 0.6858, respectively).ConclusionsThe HFO amplitude in ALS is increased, but does not predict survival.SignificanceThe enlarged HFOs in ALS might be a compensatory phenomenon to the hyperexcitability of the sensory cortex pyramidal neurons. 相似文献