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81.
We used efficiency tracing techniques to study the micelle size effect on liquid scintillation counting of the electron capture nuclide, 55Fe. We determined micelle hydrodynamic diameters for specific LS cocktails via dynamic light scattering, and sought trends in efficiencies as a function of micelle size. The presence of Fe3+ or Mn2+ ions in the cocktails did not significantly affect micelle sizes or fluorescence quenching. We did not detect any reductions in counting efficiencies due to the micelle size effect.  相似文献   
82.
The emergence of liquid biopsy using circulating tumor cells (CTCs) as a resource to identify genomic alterations in cancer presents new opportunities for diagnosis, therapy, and surveillance. We identified EML4-ALK gene rearrangement in expanded CTCs from a patient with ALK-positive lung adenocarcinoma. At the time of radiographic progression, CTCs obtained from the patient revealed a drug resistance mutation (i.e., L1196M on the ALK gene). CTCs were expanded ex vivo and drug sensitivity testing was performed using two ALK inhibitors, crizotinib and ceritinib. The half maximal inhibitory concentration of ceritinib was 1664 nM compared with crizotinib (2268 nM), showing that ceritinib was a more potent ALK inhibitor. We show that it is feasible to detect serial genetic alterations in expanded CTCs and perform in vitro drug screening. These findings support the clinical utility of CTCs not only for diagnosis, but also a potential tool for drug sensitivity testing in distinct subsets of lung cancer and for personalized precision medicine.  相似文献   
83.
microRNA表达谱的检测需要精确、高通量和多重检测方法 ,液体芯片可通过编码微球结合探针的序列差异,来检测相应的microRNA序列。本文介绍了两代液体芯片背景的FlexmiR产品,其通过锁核酸,逐步降温和单链酶解来提升对microRNA检测的特异性,为临床科研microRNA的研究提供新的检测工具。  相似文献   
84.
克拉霉素联合鼻渊舒治疗慢性鼻-鼻窦炎疗效分析   总被引:2,自引:0,他引:2  
目的 评价克拉霉素联合鼻渊舒口服液治疗慢性鼻-鼻窦炎(CRS)的疗效.方法 采用前瞻、随机、对照的临床试验方式将56例不伴鼻息肉CRS患者分为两组.对照组28例给予克拉霉素片0.25 g,次/d,连续口服3个月;治疗组28例在对照组基础上给予鼻渊舒口服液,前1个月10 ml,2次/d,后2个月10 ml,1次/d.两组的每位患者在治疗开始前均给予7~ 10日包括两种抗生素联用的综合强化治疗.采用鼻窦CT(Lund-Mackey)评分和视觉模拟量表(VAS)评分评定疗效.结果 56例患者中5例脱落,均按治疗无效病例处理.治疗组、对照组治疗后鼻窦CT得分分别为(3.28±2.11)分和(3.50±1.95)分,显著低于治疗前的(7.32±1.63)分和(7.07±1.74)分,治疗前后比较差异均有统计学意义(配对t检验,P< 0.01),均明显改善.两组鼻窦CT得分组间比较差异无统计学意义(t=0.394,P>0.05).治疗组、对照组治疗后VAS总体影响得分分别为(2.39±2.13)分和(3.86±1.37)分,显著低于治疗前的(6.21±0.92)分和(6.14±0.85)分,治疗前后比较差异均有统计学意义(配对t检验,P< 0.01),均明显改善.两组的单项症状流涕、鼻塞、头面部痛的VAS得分治疗前、后比较差异也都有统计学意义(配对t检验,P<0.01).组间比较:治疗后除流涕症状VAS得分两组差异无统计学意义外,总体影响及鼻塞、头面部痛VAS得分差异均有统计学意义,治疗组主观症状改善明显好于对照组.结论 3个月小剂量克拉霉素、鼻渊舒口服液联用和单用克拉霉素治疗不伴鼻息肉CRS都有效,但克拉霉素、鼻渊舒口服液联用疗效更好.治疗疗程开始前给予包括两种抗生素联用的短程综合强化措施对CRS抗炎治疗有益.  相似文献   
85.
目的:建立一种高效液相色谱质谱联用法同时测定黄芩苷、野黄芩苷、汉黄芩素、咖啡酸、麻黄碱、射干苷、次野鸢尾黄素、黄芩素等8种中药成分的含量及其在我院自有制剂射干合剂中的应用。方法:色谱条件:色谱柱为ZORBAX SB-C18(2.1 mm×50 mm,1.8μm),流动相为0.1%甲酸水溶液-乙腈,梯度洗脱,流速为0.3 ml·min-1,柱温:35℃;质谱条件:采用电喷雾离子源(ESI),多反应离子监测(MRM),结合正负离子扫描切换,其中咖啡酸、野黄芩苷、射干苷采用负离子模式检测,黄芩苷、汉黄芩素、次野鸢尾黄素、黄芩素、麻黄碱采用正离子模式检测。结果:黄芩苷、野黄芩苷、汉黄芩素、咖啡酸、麻黄碱、射干苷、次野鸢尾黄素、黄芩素的定量限分别为1.44×10-4,4.20×10-3,2.95×10-4,7.80,4.90×10-3,4.6×10-2,3.18×10-4,4.85 ng·ml-1,检测限分别为4.32×10-5,1.3×10-3,8.84×10-5,0.77,2.90×10-4,3.33×10-4,9.5×10-5,1.46 ng·ml-1;在相应的线性范围内R2>0.992 3;日内和日间精密度(RSD)均小于5%,平均回收率均在80%~120%。结论:本方法在20 min内实现这8种化合物的分离和测定,简单、快速、灵敏、准确,可用于射干合剂多成分含量测定。  相似文献   
86.
The application of antibiotics including fluoroquinolones to farming animals is widespread and may lead to the development of antibiotic resistance and other environmental effects. To calculate environmental loads and for a proper risk assessment it is necessary to determine the antibiotic concentration in feces. Therefore, a new liquid–liquid extraction method combined with HPLC–MS/MS for the detection of marbofloxacin, ciprofloxacin, enrofloxacin and difloxacin in chicken feces was developed. Recoveries ranged from 51.0% to 83.5%. LOQs were between 0.10 and 1.09 μg/kg. Feces of chickens treated with an enrofloxacin dosage of 10 mg/kg bodyweight revealed maximum enrofloxacin and ciprofloxacin concentrations of 61.3 and 18.8 mg/kg. Both antibiotics could be detected in feces up to two days after the last application in notable amounts (∼1 mg/kg). Thus, feces of recently medicated chickens should not be used as a fertilizer without any further processing.  相似文献   
87.
BackgroundGenital tuberculosis (TB) continues to remain an important cause of infertility in women, especially in developing countries. It is mostly consequent to a primary infection elsewhere in the body. The diagnosis is challenging, considering its paucibacillary nature. Although there are many studies on association of genital tuberculosis with infertility, there is paucity of literature on impact of extragenital tuberculosis on fertility of women through involvement of female reproductive organs. The various diagnostic modalities available have limitations and quest is ongoing for the best diagnostic test.MethodThis was a prospective observational study conducted at the infertility clinic of a tertiary care health facility where 60 infertile women with either tubal factor or unexplained infertility with or without past history of extragenital tuberculosis were enrolled as study subjects or controls respectively. Mantoux test was performed in all women and diagnostic laparo-hysteroscopy was performed in all women to look for any evidence of uterine and/or tubal damage. The peritoneal fluid was sent for GeneXpert and Liquid culture for mycobacterium tuberculosis. Results of Mantoux test, GeneXpert and liquid culture were compared with the laparohysteroscopic findings.ResultOf the thirty infertile women in the study group, 27/30 (90%) had a history of pulmonary tuberculosis and 3/30 (10%) had history of tubercular cervical lymphadenopathy. It was observed that Mantoux test was positive (induration >10 mm) in 27/30 (90%) of women in the study group as compared to only 4/30 (13.3%) controls. Abnormal hysteroscopic findings were documented in 26.6% (8/30) study group women as compared to 6.6% (2/30) women in the control group. Similarly, 60% (18/30) of women in the study group had abnormal laparoscopic findings compared to 33% (10/30) in the control group. Seven out of thirty (23.3%) women were positive for GeneXpert in the study group compared to only 1/30 (3.3%) in the control group. Similarly, liquid culture was positive in 6/30 (20%) of women in the study group as compared to 1/30 (3.3%) in the control group. All the above differences were statistically significant. We observed that the sensitivity of Mantoux test (75.8%) stand alone was higher than the other tests combined (50%). However, specificity and positive predictive value (PPV) increases markedly (up to 100%) to when all the three tests are combined.ConclusionThe authors conclude that all women presenting with infertility should be screened for a past history of tuberculosis and actively worked up for genital tuberculosis in case the history is positive. The various available tests (Mantoux test, GeneXpert and liquid culture) have their limitations for the diagnosis of genital tuberculosis. Thus an approach of early resort to laparohysteroscopy in suspected patients is desirable so that definitive management may be instituted timely and promptly.  相似文献   
88.
In this work, the bioactive peptides produced during in vitro gastrointestinal digestion of soybean seeds and soy milk were investigated. The analysis was performed on extracted protein samples from soybean seeds and milk or directly on untreated soy milk. Proteins samples were subjected to simulated gastrointestinal digestion and then analyzed by nano-liquid chromatography coupled to tandem mass spectrometry for peptide sequencing. The identified peptides were 1173 in soybean seed samples, 1364 in untreated soy milk samples and 1422 in soy milk samples in which proteins were extracted by precipitation. The peptide identifications were then employed to search specific databases and look for the presence of bioactive peptides in the investigated samples, either with known biological activity or with potential antimicrobial activity. Results pointed out that soybean proteins underwent an extensive degradation process during gastrointestinal digestion and generated a large number of bioactive peptides, some with established activity, some with predicted antimicrobial activity. Finally, the supernatants collected after protein precipitation with acetone from both soybean seeds and soy milk were also analyzed to evaluate the presence of peptides produced by the action of endogenous proteases. Likely, peptides found in soy milk samples could be formed during food processing.  相似文献   
89.
目的:建立人血浆乙酰半胱氨酸浓度测定方法,研究乙酰半胱氨酸颗粒在健康人体内的相对生物利用度与生物等效性。方法采用二制剂三周期自身对照完全三交叉试验设计,其中每位受试者有一周期不服药,健康男性受试者24例分别单剂量口服乙酰半胱氨酸受试制剂或参比制剂0.6 g。高效液相色谱串联质谱法测定血浆乙酰半胱氨酸浓度,应用DAS 3.0版统计软件计算药动学参数并评价两种制剂生物等效性。结果单剂量口服乙酰半胱氨酸颗粒受试制剂和参比制剂0.6 g的主要药动学参数:AUC0→t分别为(8547.64±2860.04)和(8783.07±4042.10)μg·h·L-1;AUC0→∞分别为(9481.64±3444.76)和(9540.51±4239.30)μg·h·L-1;Cmax分别为(1994.39±726.42)和(2090.27±885.46)μg·L-1;tmax分别为(1.18±0.60)和(1.13±0.53) h;t1/2分别为(8.60±3.76)和(7.75±5.01) h;相对生物利用度以AUC0→t和AUC0→∞计算分别为(107.0±43.3)%和(106.5±40.1)%。结论乙酰半胱氨酸颗粒两种制剂具有生物等效性。  相似文献   
90.
原有的老年学实验用果蝇饲养方法存在许多缺点。本文研究了一种以液体饲料代替原有的固体培养基饲料、以一种在底部侧面接有小嘴的三角烧瓶代替平底试管饲养果蝇的新方法。用这种方法饲养果蝇,可省去需经常配制和更换培养基的繁琐工作,并可避免果蝇的意外死亡。  相似文献   
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