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91.
目的:评价Pentacam眼前节分析仪和Keratron Scout角膜地形图仪测量瞳孔偏移量(pupillary offset)的差异和一致性。
方法:随机选取2017-11/2018-02在我院行准分子激光原位角膜磨镶术(LASIK)的患者311例604眼。术前应用Pentacam眼前节分析仪和Keratron Scout角膜地形图仪测量患者瞳孔偏移量,比较两种仪器测量结果的差异性和一致性。
结果:Pentacam眼前节分析仪和Keratron Scout角膜地形图仪测量的右眼、左眼、双眼总的offset值均有差异(P<0.05)。两种仪器测量的右眼、左眼、双眼offset轴向均无差异(P>0.05)。两种仪器测量的右眼offset值、offset轴向95%一致性界线(LoA)分别为-0.11~0.19mm、-157.01°~135.35°。左眼offset值、offset轴向95% LoA分别为-0.12~0.18mm、-150.16°~158.22°。双眼offset值、offset轴向95%LoA分别为-0.11~0.19mm、-154.30°~147.10°。
结论:Pentacam眼前节分析仪测量的瞳孔偏移量比Keratron Scout角膜地形图仪的测量值小,差异在临床可以接受的范围内。两种仪器均可以获得准确的瞳孔偏移量数据,可相互参考、校正和补充。 相似文献
92.
目的比较和分析尿液分析仪和尿沉渣镜检尿检方法的优劣。方法对我院收集的300份尿液标本进行检测,检测的方法为尿液分析仪和尿沉渣镜检,主要的评价指标:尿液中的白细胞(WBC)、红细胞(RBC)、蛋白质(PRO)。结果经过检测之后,采用尿液分析仪检测的结果中有237例为阳性,经过尿沉渣镜检检测,其中正常的有36例,假阳性率15.2%。采用尿液分析仪检测的结果中,阴性为63例,进行镜检,有8例出现异常,假阴性率12.7%。镜检检测,发现有10例患者的白细胞正常,假阳性率为19.2%。PRO和WBC两项指标都正常的患者有17例,WBC与RBC两项指标异常的患者有25例,RBC与PRO两项指标异常的有18例,PPO、WBC、RBC三项指标均异常的患者有13例。结论采用尿液分析仪进行检测,其所检测出的阴性率比较高,所以,在临床上要根据实际情况的需求来选择进行镜检。 相似文献
93.
目的:Sysmex XE-5000血液分析仪对外周血幼稚粒细胞(IG)检出与显微镜分类计数结果对比,进行评价分析及正常临界值的设定。方法:Sysmex XE-5000血液分析仪对438份血标本采用白细胞分类检测通道(CBC+DIFF通道)检测幼稚粒细胞,并用显微镜人工计数IG。结果:Sysmex XE-5000血液分析仪和显微镜镜检法对IG检出呈正相关(r=0.76),SysmexXE-5000血液分析仪对IG%检测的敏感性为62.9%,特异性为83.4%,临界值>0.6。正常组的IG检测人工镜检均未见幼稚粒细胞,仪器检测显示IG%范围为00.6(x±3s)。结论:当Sysmex XE-5000血液分析仪检测结果 IG%≤0.6[或绝对值(IG#)≤0.1×109/L]可认为是正常标本,当IG%>0.6[或绝对值(IG#)>0.1×109/L)则为异常标本,应进行血涂片复查以明确诊断。 相似文献
94.
氨基酸分析仪法(过甲酸氧化)测定复方氨基酸注射液(18AA)中胱氨酸的含量 总被引:1,自引:0,他引:1
目的 建立测定复方氨基酸注射液(18AA)中胱氨酸的含量方法。方法 采用柱前衍生-氨基酸分析仪测定。结果 胱氨酸在20.46∽184.10 g.mL 1内呈良好的线性关系(r=0.999 8),平均回收率为100.8%,RSD(n=9)为0.91%。结论 本法专属性强、准确、快速、灵敏,可用于测定复方氨基酸注射液中胱氨酸的含量。 相似文献
95.
96.
William B. Homoky Tim M. Conway Seth G. John Daniela Knig FeiFei Deng Alessandro Tagliabue Rachel A. Mills 《Proceedings of the National Academy of Sciences of the United States of America》2021,118(13)
Dissolution of marine sediment is a key source of dissolved iron (Fe) that regulates the ocean carbon cycle. Currently, our prevailing understanding, encapsulated in ocean models, focuses on low-oxygen reductive supply mechanisms and neglects the emerging evidence from iron isotopes in seawater and sediment porewaters for additional nonreductive dissolution processes. Here, we combine measurements of Fe colloids and dissolved δ56Fe in shallow porewaters spanning the full depth of the South Atlantic Ocean to demonstrate that it is lithogenic colloid production that fuels sedimentary iron supply away from low-oxygen systems. Iron colloids are ubiquitous in these oxic ocean sediment porewaters and account for the lithogenic isotope signature of dissolved Fe (δ56Fe = +0.07 ± 0.07‰) within and between ocean basins. Isotope model experiments demonstrate that only lithogenic weathering in both oxic and nitrogenous zones, rather than precipitation or ligand complexation of reduced Fe species, can account for the production of these porewater Fe colloids. The broader covariance between colloidal Fe and organic carbon (OC) abundance suggests that sorption of OC may control the nanoscale stability of Fe minerals by inhibiting the loss of Fe(oxyhydr)oxides to more crystalline minerals in the sediment. Oxic ocean sediments can therefore generate a large exchangeable reservoir of organo-mineral Fe colloids at the sediment water interface (a “rusty source”) that dominates the benthic supply of dissolved Fe to the ocean interior, alongside reductive supply pathways from shallower continental margins.Sediments undergo early diagenetic transformations that are understood to provide an important source of dissolved iron (dFe) to the ocean that is used to fuel primary production and secondary food webs, fix nitrogen, and support the air–sea transfer of carbon dioxide (1, 2). Nevertheless, fundamental questions remain concerning the magnitude of dFe released from ocean sediments and the mechanisms through which this supply may be moderated. Such uncertainty is most acute in oxic and deep-water regions, which bear the fewest observations, but represent the largest area of the ocean sediment–water interface (3). Here, comparatively small sedimentary releases of dFe have the cumulative potential to enhance the dFe inventory of the deep ocean and—in so far as it connects with surface water—relieve iron deficiency for phytoplankton. Porewaters in these deep-water regions maintain a persistently oxic and/or nitrogenous state adjacent to bottom waters that is largely unexamined for its role in the marine iron cycle. These gaps in knowledge hinder our ability to make more accurate simulations of the carbon cycle in ocean biogeochemical models (4).Two principle processes are thought to be driving Fe dissolution from sediments that underpin the magnitude and variability of dFe inputs to the ocean. The first is a reductive-dissolution (RD) process, which demonstrably occurs during early diagenetic oxidation of organic carbon (OC) and produces high abundances of reduced, soluble, and isotopically light Fe in ferruginous porewaters, generally beneath the Fe-oxidizing fronts of nitrous oxides and oxygen (5–7). The second is a nonreductive-dissolution (NRD) process to account for the comparatively unfractionated or heavy isotope compositions of dFe attributed to sedimentary inputs in some oxygenated regions of the open ocean (8) and in the oxic zones of marine sediment porewaters (9), but the mechanisms governing so-called NRD in oxic sediments are unclear.RD of Fe is coupled to OC oxidation and is widely observed in shallow porewater in sediments with high-oxygen consumption rates, under productive shelf seas, near zones of upwelling, and overlain by oxygen-depleted seawater (10). Low seawater oxygen content serves to enhance the efflux of reduced and soluble Fe (sFe, filtered <0.02 µm) from ferruginous porewaters and enables sFe(II) to propagate further in the water column (11–14). Subsequently, without sufficient chelation by organic ligands sFe(II) will be lost to oxidative precipitation (7, 15, 16), scavenging (12), and sedimentation in deeper water (16, 17). Sedimentary RD provides a key component of the ocean’s dFe inventory that is most pronounced in the upper ocean (1, 10, 11, 13). It is also the only mechanism by which most ocean biogeochemical models simulate the sedimentary release of dFe (4), since model parameterizations rely on empirical relationships between dFe fluxes, OC oxidation rates, bottom water oxygen contents, and/or water depth (1, 11, 18, 19).NRD is a term previously used to describe a sedimentary source of isotopically heavy dFe to the water column (8) and has since been used to describe the presence of lithogenic isotope compositions observed in oxidizing zones from some deep ocean sediment porewaters (9). Similar observations have become commonplace in the ocean interior (20–23), such that nonreductive sedimentary processes appear to be important for the ocean’s dFe inventory. However, the detection of lithogenic dFe isotope signatures in porewaters (6, 9), within western North Atlantic benthic nepheloid layers, and in the water column far from sediment sources have been difficult to explain (24). The role played by this additional source of dFe is not yet included in global ocean models.Based on the very low solubility of silicate minerals and Fe(III) oxides in circumneutral pH and oxygenated seawater, NRD ought to be incapable of sustaining a benthic flux of dFe to the ocean without significant chelation by organic ligands (25). Because of a strong isotope fractionation effect, however, ligand complexation of Fe would produce a much heavier Fe isotope signal in the ocean (26), which is at odds with the isotopic evidence for NRD (20–23). To reconcile these differences between NRD theories and dFe isotope observations, we need to consider any physicochemical partitioning within the dFe pool. The abundance and isotope composition of dFe (<0.2 µm) may reflect variable contributions of mineral or organo-mineral Fe colloids (cFe, 0.02 to 0.2 µm) in addition to any ligand-bound Fe and sFe(II/III) species (<0.02 µm) in the ocean (23, 27). Such components of the dFe pool are often unaccounted for and have been neglected in previous studies reporting the occurrence of sedimentary NRD in the water column. However, sizable concentrations of cFe (101 µmoles ⋅ L−1) have been observed in oxic-nitrogenous porewaters from deep ocean turbidites of the Southern Ocean, where dFe isotope compositions also matched the solid phase inputs from ocean island basalt. Whether these colloids were formed in situ through organic complexation and/or as secondary minerals from either reductive or nonreductive processes was unresolved. A comparison to fresh tephra layers in the Caribbean Sea showed that ocean island basalt weathering and production of nanoscale ferrihydrite or Fe-bearing smectite clays were thermodynamically plausible explanations for cFe in the Southern Ocean porewaters (28). Recently, Klar et al. (7) looked for Fe colloids in porewaters from a shallow shelf sediment, but found few if any, and that the porewaters were dominated by light dFe isotope signatures and sFe(II) attributable to RD by bacteria. Previous studies have not resolved where or why cFe occurs in sediment porewaters of the continental shelf–slope–basin transition or the extent to which they may influence the inventory and isotope composition of dFe input to the ocean (20, 22). These lessons need to be learned by examining the soluble and colloidal partitioning of dFe in porewaters and comparing them to dFe isotope signatures from a wider range of sedimentary carbon and oxygen regimes in the ocean environment.Without appropriate simulation of this dFe source, ocean biogeochemical models will fail to represent spatial patterns in dFe flux from the seafloor, the response of these fluxes to changing ocean environments, and their consequences for ocean biogeochemistry. Confounding this issue is the omitted role of advective transport mechanisms, internal waves, and benthic boundary layers that will facilitate exchanges between oxic sediments and the ocean interior (3, 29, 30). To make progress on this important issue, we require new understanding on the mechanisms by which Fe dissolves and is supplied to the ocean by oxic sediments.Herein, we present findings from surface sediment cores from sites that span the depth and breadth of the Southwest Atlantic Ocean. The UK-led GEOTRACES expedition, GA10W, recovered porewaters in 2011 from the Uruguayan continental shelf and slope, Argentine abyssal floor, and Mid-Atlantic Ridge (SI Appendix, Table S1). We report porewater dFe isotope compositions and further evidence of the physicochemical partitioning of dFe between soluble and colloidal size fractions (where cFe = dFe−sFe) at selected locations and depths where porewater inventories of Fe were sufficient to permit these determinations. We apply principles of isotope fractionation and mass balance across the dissolved and soluble size classes to test hypothetical controls on the dFe pool in these porewaters. Our study reveals that oxidizing zones of marine sediments are important regions of nonreductive cFe production derived from lithogenic material, which ultimately determine the dFe inventory and isotope composition supplied to the deep ocean. 相似文献
97.
目的:分析用AVE-763B型自动尿沉渣分析仪检测红细胞的影响因素。方法:采用AVE-763B型自动尿沉渣分析仪和显微镜检测法分析了545份住院患者的尿液标本,并将二者结果进行比较。结果:AVE-763型尿沉渣全自动检测仪检测标本红细胞的假阳性率为15.2%,假阴性率为0,灵敏度为100%,特异度为84.8%。与显微镜检测法相比,差异有统计学意义(P〈0.05)。结晶、上皮细胞核、酵母菌等是影响AVE-763B型自动尿沉渣分析仪检测结果的主要因素。结论:为获得准确可靠的尿红细胞检测结果,应以AVE-763B型自动尿沉渣分析仪进行筛查并结合显微镜检查。 相似文献
98.
目的:对倍肯野战(应急)快速检验系统A型中的电解质、生化分析模块的结果与常规生化分析仪所测定结果进行比较,分析两者之间的差异。方法:利用倍肯野战(应急)快速检验系统A型的电解质分析模块(IMARA)、生化分析模块(SP4430)与日本OLYMPUSAU5421全自动生化分析仪、BH5500S微量元素原子吸收光谱检测仪对200例标本K+、Na+、iCa2+、GLU、CREA、UA、ALT、ALB、TBIL、LDH、AMS进行平行测定,并对检测结果分别进行比较分析。结果:分析表明不同仪器所测K+、Na+、iCa2+、GLU、UA、ALB的结果差异无统计学意义,而CREA、ALT、TBIL、LDH和AMS所测结果其差异有统计学意义(t=114.247,t=64.229,t=37.568,t=27.708,t=66.841;P〈0.01)。所有11项检测结果的相关性系数均〉0.90。结论:倍肯野战(应急)快速检验系统A型中的电解质、生化分析模块与常规实验室生化分析仪检测结果相关性良好,由于检测方法不同,部分结果差异较大,但仍然具有可比性。 相似文献
99.
目的:对野战(应急)快速检验系统血细胞分析模块性能进行评价。方法:对该模块在室内环境与模拟野战环境下进行精密度评价,并对两种环境下的评价结果进行对比;利用该模块和Sysmex XE-2100血细胞分析仪对200例标本进行平行检测,分析其可比性。结果:该模块测定红细胞比容(HCT)、血红蛋白(Hb)、白细胞(WBC)和血小板(PLT)的变异系数(CV)值在室内环境中分别为0.24%、0.23%、1.40%、2.94%,在模拟野战环境下分别为1.29%、1.53%、2.25%、1.95%;两种环境结果比较其差异无统计学意义(t=0.380,t=0.206,t=1.935,t=1.329;P>0.05)。两台仪器HCT,Hb,WBC,PLT的相关性系数分别为0.981、0.986、0.962、0.977。结论:在室内和模拟野战环境下,野战(应急)快速检验系统血细胞分析模块精密度良好,结果对比无显著差异;该模块与常规血细胞分析仪检测结果无显著性差异,且一致性良好。 相似文献
100.
目的探讨恶性胸腔积液(malignant pleural effusion,MPE)中非小细胞肺癌(non-small cell lung cancer,NSCLC)上皮细胞-间质转化(epithelial-mesenchymal transition,EMT)相关分子标志物的表达及意义。方法对823例胸水标本进行液基细胞薄层检测(thinPrep cytology test,TCT),结合活检结果确诊107例NSCLC标本,随机分成NSCLC细胞组、NSCLC活检组及NSCLC癌旁组织组三组,对其中39例NSCLC细胞组胸水标本进行沉渣后包埋、切片,采用免疫组化SP法检测三组中vimentin、E-cadherin、N-cadherin、β-catentin的表达,并进行对比分析。结果E-cadherin、β-catentin阳性/异常阳性率在NSCLC细胞组、活检组均明显低于癌旁组织组(P<0.05)。NSCLC细胞组、活检组N-cadherin、vimentin的阳性率均明显高于癌旁组织组(P<0.05)。同时亦发现,在NSCLC细胞组中,E-cadherin表达与分化程度和淋巴结转移有关(P<0.05),β-catentin异常阳性与分化程度有关(P<0.05),N-cadherin与vimentin表达与淋巴结转移有关(P<0.05)。以上4个抗体表达/异常表达均与患者年龄、性别、吸烟史和组织学分型无关(P>0.05)。结论MPE中NSCLC细胞具备EMT表型,从细胞学角度进一步证实EMT现象存在于NSCLC,为新的靶向治疗药物的研究和治疗靶点提供新思路。 相似文献