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71.
Dean E. Morbeck 《Journal of assisted reproduction and genetics》2015,32(7):1019-1024
Quality of air in the clinical embryology laboratory is considered critical for high in vitro fertilization (IVF) success rates, yet evidence for best practices is lacking. Predominantly anecdotal reports on relationships between air quality and IVF success rates have resulted in minimal authentic clinical laboratory guidelines or in recommendations that are based on industrial cleanroom particulate standards with little attention to chemical air filtration. As a result, a nascent industry of costly, specialized air handling equipment for IVF laboratories has emerged to provide air quality solutions that have not been clearly assessed or verified. Clinics are embracing such technology because their embryology laboratories have become epicenters of assisted reproductive technology as the practice of IVF has moved to blastocyst transfers and utilization of trophectoderm biopsy for preimplantation genetic testing (PGT). Thus, a laboratory’s ability to culture, biopsy, and freeze blastocysts is a rate-limiting step that depends on technical proficiency and a supportive and stable culture environment based on a foundation of high-quality ambient air. This review aims to describe how evidence for the importance of air quality, in particular the role of volatile organic compounds (VOC), has resulted in an evolution of clinical practice that has arguably contributed to improved outcomes. 相似文献
72.
目的:筛选中药三棱抗血栓活性部位并对其化学成分进行研究。方法:采用斑马鱼血栓模型对中药三棱80%乙醇提取物的石油醚部位、乙酸乙酯部位、正丁醇部位和水部位的抗血栓作用进行测试。以硅胶柱色谱等方法对抗血栓作用显著的部位进行分离纯化,通过NMR,MS等方法并结合文献数据鉴定化合物结构。结果:乙酸乙酯萃取物能显著增加斑马鱼血栓模型的心脏染色强度(P<0.01),其余各部位抗血栓作用不明显。在该部位分离得到11个化合物,分别鉴定为对羟基苯甲酸(1)、5-羟甲基糠醛(2)、对甲氧基苯甲醛(3)、对羟基苯甲醛(4)、对香豆酸(5)、阿魏酸(6)、香草酸(7)、原儿茶酸(8)、香兰素(9)、Methyl-3,6-dihydroxy-2-[2-(2-hydroxyphenyl)-ethynyl]benzoate (10)及1,3-O-二阿魏酰基甘油(11)。结论:三棱提取物的乙酸乙酯萃取部位具有显著的抗血栓作用,其主要化学成分为酚酸类化合物。 相似文献
73.
Subashini Chandrapalan 《Expert review of molecular diagnostics》2020,20(5):489-496
ABSTRACTIntroduction: The increasing incidence of colorectal cancer (CRC) in young adults warrants early and preferably noninvasive diagnostic modalities. Although the current stool-based assays have had good performance indicators for CRC detection, the overall poor uptake remains a challenging issue. However, alternative blood and urine markers are emerging.Areas covered: This paper discusses the various urinary biomarkers available for the detection of CRC. The more commonly encountered drawbacks are the small number of studies and the size of the study population. We discuss the role of microRNA and ProstaglandinE2 in CRC detection. The emergence of new, low-cost technologies, specifically in the detection of volatile organic compounds (VOCs), presents a promising future. We postulate possible mechanisms for the origin of these VOCs in urine and their role in carcinogenesis.Expert opinion: Urinary biomarkers provide an alternative option to the stool-based screening tests. MicroRNA and ProstaglandinE2 have shown utility in CRC detection. Evidence so far suggests that VOCs could also be a potential biomarker for the detection of CRC. In addition to its interaction within the colon lumen, this altered ‘VOC signature’ might also play a role in carcinogenesis. Low-cost technology may enable such diagnostic methods to be utilized at the point of care. 相似文献
74.
《Dental materials》2020,36(2):257-269
ObjectivesTo assess the release and apical extrusion of toxic volatile compounds and disinfection by-products during instrumentation and irrigation of artificially infected root canal specimens, with sodium hypochlorite and ethylene diamine tetra acetic acid.MethodsForty-two single-rooted human teeth were decoronated to obtain 15 mm-long root specimens and working length was determined 1 mm short of root apex. All specimens were initially preflared, to create sufficient conical space for the development of a nutrient-stressed multispecies biofilm. The specimens were randomly assigned into three groups [Group 1; no endodontic intervention, Group 2; instrumentation with rotary files and irrigation with sterile saline, Group 3; instrumentation with rotary files and irrigation with 2.5% sodium hypochlorite (NaOCl) and 17% ethylene diamine tetra acetic acid (EDTA)]. A customised experimental model apparatus was fabricated for each specimen. The apical root third was inserted in a glass vial filled with sterile ultrapure water, to simulate high-compliance periradicular space. The reaction products of the aliquots obtained from the glass vials were analysed in real time, by selected ion flow tube mass spectrometry (SIFT-MS) in triplicates. Two-way analysis of variance (ANOVA) with post hoc Tukey tests were used for data analysis. The level of statistical significance was set at P < 0.05.ResultsThe group of teeth that were not subjected to endodontic intervention did not show any volatile compounds (VOCs) or disinfection by products (DBPs) whilst instrumentation and irrigation of root canals (Groups 2 and 3) resulted in the apical extrusion of VOCs and DBPs. In Group 3, the aliquots obtained from periradicular space released high concentrations of methanol, propanol, ammonia, chloroform, together with unexpected higher levels of formaldehyde, which were statistically significant compared to Group 2 (P < 0.05).SignificanceThe mechanical preparation and irrigation of artificially infected root canals with rotary files, 2.5% NaOCl and 17% EDTA resulted in the formation of toxic VOCs and DBPs in a water-closed periradicular space. The chemical interaction of NaOCl and EDTA resulted in the generation of high concentrations of formaldehyde. The formation of chloroform and formaldehyde indicate that risk assessment of the potential hazards to health should be carried out. 相似文献
75.
Takashi Yorifuji Yoko Kado Midory Higa Diez Toshihiro Kishikawa Satoshi Sanada 《Archives of environmental & occupational health》2016,71(3):170-177
In the 1950s, large-scale food poisoning caused by methylmercury was identified in Minamata, Japan. Although severe intrauterine exposure cases (ie, congenital Minamata disease patients) are well known, possible impacts of methylmercury exposure in utero among residents, which is likely at lower levels than in congenital Minamata disease patients, are rarely explored. In 2014, the authors examined neurological and neurocognitive functions among 18 exposed participants in Minamata, focusing on fine motor, visuospatial construction, and executive functions. More than half of the participants had some fine motor and coordination difficulties. In addition, several participants had lower performance for neurocognitive function tests (the Rey-Osterrieth Complex Figure test and Keio version of the Wisconsin card sorting test). These deficits imply diffuse brain damage. This study suggests possible neurological and neurocognitive impacts of prenatal exposure to methylmercury among exposed residents of Minamata. 相似文献
76.
77.
《Yao wu shi pin fen xi = Journal of food and drug analysis.》2014,22(4):431-438
The volatile and odor-active compounds in cooked meat of farmed obscure puffer (Takifugu obscurus) were analyzed by gas chromatography–mass spectrometry–olfactometry (GC–MS–O). The volatile compounds were extracted by the simultaneous distillation–extraction (SDE) method, then separated and identified by GC–MS. Odor-active compounds in the SDE extract were characterized by GC–MS–O. A total of 68 volatile compounds were found, including 23 aldehydes, 10 alcohols, nine ketones, 17 N- or S-containing compounds and aromatics, three acids, three alkanes, and three esters. Of these, 31 odor-active compounds were detected and identified. Trimethylamine (fishy), octanal (grassy, leafy, green), (E)-2-octenal (roast, fatty), 1-octen-3-ol (fishy, fatty, mushroom, grassy), 2-ethyl-1-hexanethiol (cooked fish), (E,E)-2,4-octadienal (cooked meat, sweet), 2-acetylthiazole (meaty, roast, nutty, sulfur), 2-acetylpyrrole (nutty, walnut, bread) were identified as the key odorants in the cooked meat of farmed obscure puffer based on posterior intensity and time-intensity methods. 相似文献
78.
79.
Xinning YU Jinghua FANG Jianyang LUO Xianyan YANG Dongshuang HE Zhongru GOU Xuesong DAI 《浙江大学学报(医学版)》2016,45(2):126
目的初步构建基于软骨钙化层损伤重建的有机—无机复合组织工程支架,探究掺镁硅灰石含量与支架抗压性能之间的关系。方法利用质量分数分别为1%、3%、5%的高生物活性钙镁硅酸盐超细颗粒复合Ⅰ型胶原—透明质酸钠进行三维打印,经海藻酸钠—氯化钙气雾交联成型,电镜下观察表面孔隙、孔径、无机相分布,万能材料试验机测试抗压性能,并计算支架孔隙率。结果支架表面平均孔径(212.3±34.2)μm,平均孔隙率(48.3±5.9)%,不同质量分数的高生物活性钙镁硅酸盐超细颗粒复合Ⅰ型胶原—透明质酸钠支架压缩模量差异无统计学意义( P>0.05),平均压缩模量(7.2±1.2)MPa,介于软骨和软骨下骨之间。 结论利用三维打印技术成功构建出多孔钙化层仿生重建支架,可为今后研制多层次复合支架治疗骨—软骨损伤奠定基础。 相似文献
80.
L. X. Peng L. Zou J. B. Wang J. L. Zhao D. B. Xiang G. Zhao 《Indian journal of pharmaceutical sciences》2015,77(6):661-667
The rutin, quercetin concentrations, antioxidant activity, and aroma compounds in different commercial tartary buckwheat tea were analyzed in our study. Results revealed that the materials and the processing protocol affected the chemical composition and activity of tartary buckwheat tea. Rutin and quercetin concentrations, antioxidant activity were significantly different in various kinds of tartary buckwheat tea, where the whole bran tea and the whole plant tea had the lower rutin, but higher quercetin concentrations and higher antioxidant activity. The whole embryo tea had the converse results. There was strong correlation between quercetin concentration and antioxidant activity (r>0.98, P<0.05). Meanwhile, Twenty eight different aroma compounds in tartary buckwheat tea were identified by gas chromatography-mass spectrometry. Those compounds were mainly composed of pyrazine, aldehydes, fatty acids and ketones. The main type of aroma compounds in different tartary buckwheat tea were similar, but their relative contents were different. The implications to the quality control of buckwheat tea were extensively discussed. 相似文献