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1.
本文采用放射免疫法测定了144例恶性肿瘤患者血清CEA含量,并以同样条件测定了30例正常人作为对照。结果表明恶性肿瘤患者血清CEA含量显著高于健康人,均值为10.3±4.84ng/ml。不同肿瘤患者血清CEA升高的程度不等,其中以肺癌含量最高为14.7±7.83ng/ml。转移性肿瘤CEA含量高于144例肿瘤的平均水平。术后复发者含量不见下降。癌性胸腹水中CEA含量明显升高。因此,血清CEA的测定对恶性肿瘤的辅助诊断,评价疗效和判断预后具有重要的临床意义。 相似文献
2.
高效毛细管电泳柱上富集测定福莫特罗干糖浆 总被引:1,自引:0,他引:1
研究了低规格药物福莫特罗干糖浆的含量测定。方法采用高效毛细管电泳柱上富集的方法则定。电压进样,10KV,20s,运行电压20KV,运行缓冲液为80mmol.L^-1磷酸盐缓冲液;检测波长为200nm。结论本法简便,准确,重现性,样口柱上富集260倍。 相似文献
3.
近几十年来,阴、阳离子检测方法的发展非常迅速,检测方法有了较大的改进,同时离子种类得到很大的丰富。根据不同的药物分析目的可选择不同的检测方法,以取得最好的检测精度和灵敏度。简要地介绍了用于检测药物中常用的阴、阳离子的比浊法、比色法、滴定法、离子选择电极法、可见-紫外分光光度法、原子吸收分光光度法与色谱法等分析方法,并对今后的研究方向进行了展望。 相似文献
4.
Kevin M. Kransler Ammie N. Bachman Richard H. McKee 《Regulatory toxicology and pharmacology : RTP》2012
Di-isononyl phthalate (DINP) is a high molecular weight general purpose plasticizer used principally in the manufacture of flexible polyvinyl chloride (PVC) articles. DINP metabolites can be measured in biological media such as blood and urine. However, measurement of a substance in the blood or urine does not by itself mean that the chemical causes or is associated with adverse health outcomes. This is particularly pertinent given the advances in modern analytical techniques whereby ever diminishing trace amounts of substances can be detected. Therefore, it is a scientific necessity that risk assessors understand the relationship of biomonitoring data to estimation of exposure so that appropriate comparisons can be made to the no observed adverse effects levels (NOAELs) or other points of departure from toxicological studies in animals. In this paper, estimates of daily DINP intake are calculated for various population segments based on urinary biomonitoring data and are compared to estimates of exposure based on indirect methods and to health-based exposure guidance values. In general, intake estimates converge on a mean of 1–2 μg/kg/day regardless of source of exposure or population cluster; a value 2-orders of magnitude lower than health-based exposure guidance values, ranging from 120 to 290 μg/kg/day, which have been established by regulatory authorities and other authoritative bodies as representing acceptable levels. 相似文献
5.
目的:探讨正常儿童胫后神经(PTN)体感诱发电位(SEP)的特点及正常值。方法:对121名正常儿童进行PTN—SEP检测,分析各波的特点及各波参数随年龄变化规律。结果:PTN—SEP随年龄增长,波幅增高,使波容易辨认,波幅在个体问变异较大。左右双侧对应波的潜伏期(PL)和峰间期(IPL)比较差异无显著意义(P〉0.05),各组男女间PL和IPL无性别差异(P〉0.05)。外周神经电位的腰髓电位(LP)、马尾电位(cE)、胭窝电位(PF)等3个波的潜伏期随年龄增长PI。延长,而P40和N45等皮层电位的PL在8岁前变化则不明显(相邻组间P〉0.05),8岁后延长明显。PF-T12的IPL也随年龄增长而延长(相邻组间P〈0.05);而T12-P40IPL3岁组较1岁组延长,但差异不明显,以后随年龄增长而缩短,6岁组达成人值。结论:儿童PTN—SEP的正常值按年龄组划分是完全必要的。由于各波PL受身长的影响大,因此绝对PL不宜作为PTN—SEP的异常标准。PTNSEP是评价小儿躯体感觉通路、脊髓、脑干和大脑功能的客观指标,具有较大的临床实用价值。 相似文献
6.
Naoko Iwakami Shin-ichiro Iwakami Munechika Hara Mitsuaki Sekiya Takashi Dambara Kazuhisa Takahashi 《Respiratory investigation》2018,56(3):238-242
Background
It is well known that ultrasound-guided needle-aspiration (USGNA) for intrapulmonary subpleural lesion in contact with the pleura is useful and safe, and its diagnostic yield is high. However, reports concerned with the analyses of cases with intrapulmonary subpleural lesion which could not be diagnosed using USGNA are limited. The objective of this study is to clarify the radiological properties of subpleural primary lung cancer which obstruct diagnosis by USGNA.Methods
The consecutive cases with subpleural primary lung cancer whose radiological properties could be confirmed by thoracic computed tomography (CT) without contrast enhancement (CE), and examined by USGNA at our hospital between January 1999 and December 2014 have been analyzed. All cases were given pathological diagnoses of primary lung cancer. The diagnostic yield by USGNA was calculated, and the properties of the lesions of the subjects were analyzed by means of thoracic CT without CE images and pathological findings.Results
87 consecutive cases (41–86 year olds, 75 males, 12 females) were analyzed. The overall diagnostic yield by USGNA was 86.2%. There was no statistically significant difference regarding the diagnostic yield concerning radiological properties such as cavities, small airspaces and low density areas in the lesions and their sizes. However, the diagnostic yield for the cases with squamous cell carcinoma was statistically significantly low (p=0.02).Conclusion
Although the diagnostic yield of USGNA is not distorted by the radiological properties of lesions, it is statistically significantly low in cases with squamous cell carcinoma. 相似文献7.
8.
Keiko Nishizawa Kenta Teruya Ayumi Oguma Yuji Sakasegawa Hermann Schätzl Sabine Gilch Katsumi Doh-ura 《Journal of pharmaceutical sciences》2019,108(8):2814-2820
Prion accumulation in the brain and lymphoreticular system causes fatal neurodegenerative diseases. Our previous study revealed that cellulose ethers (CE) have anti-prion activities in vivo and in prion-infected cells when administered at high doses. This study aims to improve the bioavailability of a representative CE using a liposomal formulation and characterized CE-loaded liposomes in cultured cells. The liposomal formulation reduced the EC50 dose of CE by <1/200-fold in prion-infected cells. Compared to empty liposomes, CE-loaded liposomes were taken up much more highly by prion-infected cells and less by macrophage-like cells. Phosphatidylserine modification reduced the uptake of CE-loaded liposomes in prion-infected cells and did not change the anti-prion activity, whereas increased the uptake in macrophage-like cells. Polyethylene glycol modification reduced the uptake of CE-loaded liposomes in both types of cells and reduced the anti-prion activity in prion-infected cells. These results suggest that a liposomal formulation of CE is more practical than unformulated CE and showed that the CE-loaded liposome uptake levels in prion-infected cells were not associated with anti-prion activity. Although further improvement of the stealth function against phagocytic cells is needed, the liposomal formulation is useful to improve CE efficacy and elucidate the mechanism of CE action. 相似文献
9.
10.