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71.
目的:观察光照对粗茎秦艽种子萌发及其过程中环烯醚萜类成分积累规律的影响。方法:将粗茎秦艽种子分为光照组和避光组,浸泡24 h后置于21℃培养箱内培养,光照组的光照强度为605~710 lx。以种皮开裂露出胚根为发芽标志,记录每日种子的发芽情况。培养33 d后,分别统计光照组和避光组的种子发芽率、首次萌发时间与半数萌发时间,测量其子叶、胚轴、胚根的长度及胚轴直径。于培养过程中不同时间点取样,液质联用技术定性鉴别环烯醚萜类化合物,并对各成分含量进行相对定量分析。比较光照组和避光组种子萌发过程中环烯醚萜类成分含量的变化趋势。结果:①培养33 d后,光照组平均发芽率为76%,避光组平均发芽率为88%;光照组种子首次萌发时间略晚于避光组;光照组和避光组的半数萌发时间分别为培养16、15 d。②避光组子叶未见发育,光照组子叶发育明显。避光组的胚轴长度和胚轴直径明显大于光照组(P0.01),光照组的胚根长度明显大于避光组(P0.01)。③液质联用定性鉴别出8种环烯醚萜类化合物。种子萌发过程中,龙胆苦苷含量逐渐增加,而马钱苷酸含量逐渐减少;环烯醚萜衍生物gentistraminosides B、macrophylloside A、macrophylloside B及其同分异构体含量逐渐增加。光照组的龙胆苦苷和以上4种环烯醚萜衍生物的含量高于避光组。结论:光照对粗茎秦艽种子萌发及其胚轴伸长具有一定抑制作用,并对萌发过程中环烯醚萜类成分的积累产生影响。 相似文献
72.
Shinnosuke Nakamura Madoka Inui Yoshihiko Matsumura Takashi Takeoka Kenya Okumura Toshiro Tagawa 《Journal of maxillofacial and oral surgery》2013,12(2):224-227
We present a case of carcinoma ex pleomorphic adenoma on the right buccal mucosa in a 52-year-old Japanese woman. Based on the histopathology, the excised tumor was the non-invasive type, but the majority of the tumor consisted of poorly-differentiated adenocarcinoma cells. We performed proton radiation after the surgery. The patient was well, without evidence of disease, 48 months after surgery. Carcinoma ex pleomorphic adenoma in the buccal mucosa has been reported in only four cases during the past twenty years. Therefore, our case was comparatively rare. 相似文献
73.
目的建立一种UPLC-Q-Orbitrap HRMS定量分析方法,同时测定秦艽炮制前后8种化学成分(龙胆苦苷、马钱苷酸、獐牙菜苦苷、獐牙菜苷、木犀草素、异牡荆素、芹菜素、山柰酚)含量的变化。方法采用Waters Acquity UPLC BEH C_(18)(100 mm×2.1 mm,1.7μm)色谱柱,以甲醇-0.1%甲酸水溶液为流动相进行梯度洗脱,体积流量0.3 mL/min,柱温35℃。质谱采用负离子检测模式进行检测。结果秦艽经清炒、酒炙后环烯醚萜类含量均明显升高,且清炒后龙胆苦苷和马钱苷酸含量具有统计学差异。黄酮类在清炒和酒炙后含量变化不大。2类成分总的含量变化为环烯醚萜类成分含量清炒酒炙生品;黄酮类成分含量生品酒炙清炒。结论建立的UPLC-Q-Orbitrap HRMS同时测定秦艽炮制前后8种成分的方法准确、稳定,为进一步研究秦艽炮制前后主要成分的变化奠定了基础。 相似文献
74.
目的 基于抗炎活性成分研究苗药羊耳菊药材质量控制方法。方法 建立羊耳菊有效组分中代表性、特征性化学成分作为指标成分的多指标定量指纹图谱研究。通过多指标成分定量结合指纹图谱分析评价贵州不同产地羊耳菊的质量。结果建立了35批贵州产羊耳菊的高效液相指纹图谱和多指标含量测定方法;指认了羊耳菊药材液相色谱指纹图谱17个共有峰中的8个,结果显示相似度在0.898~0.997,以8个化学成分作为指标,对其进行含量测定,结果显示绿原酸、新绿原酸、隐绿原酸、异绿原酸B、异绿原酸A、异绿原酸C、洋蓟素、木犀草苷的质量分数分别为0.353~3.765、0.056~0.495、0.086~0.526、0.306~2.526、0.861~7.353、0.729~4.268、0.052~0.424、0.148~1.102mg/g。结论 所建立的基于抗炎活性成分的指纹图谱和多指标含量测定研究方法,灵敏度高、准确度好、稳定可靠,可用于苗药羊耳菊药材的质量控制。 相似文献
75.
Platelet sequestration and activation during GalTKO.hCD46 pig lung perfusion by human blood is primarily mediated by GPIb,GPIIb/IIIa,and von Willebrand Factor
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Lars Burdorf Andrea Riner Elana Rybak Isabelle I. Salles Simon F. De Meyer Aakash Shah Kevin J. Quinn Donald Harris Tianshu Zhang Dawn Parsell Franchesca Ali Evan Schwartz Elizabeth Kang Xiangfei Cheng Evelyn Sievert Yuming Zhao Gheorghe Braileanu Carol J. Phelps David L. Ayares Hans Deckmyn Richard N. Pierson III Agnes M. Azimzadeh 《Xenotransplantation》2016,23(3):222-236
76.
In utero congenital malformations in the fetus can occasionally lead to an obstructed airway at birth accompanied by hypoxic injury or peripartum demise, without intervention. Ex utero intrapartum treatment (EXIT) may help reduce morbidity and mortality associated with challenging airways by providing extra time on uteroplacental circulation to secure the airway. Meticulous preparation and planning are crucial for this procedure. Many different types of congenital malformations can result in a difficult airway, but there is no correlation between specific malformations and a required type of airway intervention. Based on our experience and literature review, an airway process flow diagram has been created to help assist teams in decision‐making for airway intervention in a neonate during the EXIT procedure. The management of the airway in this scenario involves additional unique considerations that accompany handling a partially delivered newborn in the uterine environment. Extensive preparation and team rehearsal are essential to the success of this procedure. 相似文献
77.
78.
SARS-CoV-2 has spread across the globe with an astonishing velocity and lethality that has put scientist and pharmaceutical companies worldwide on the spot to develop novel treatment options and reliable vaccination for billions of people. To combat its associated disease COVID-19 and potentially newly emerging coronaviruses, numerous pre-clinical cell culture techniques have progressively been used, which allow the study of SARS-CoV-2 pathogenesis, basic replication mechanisms, and drug efficiency in the most authentic context. Hence, this review was designed to summarize and discuss currently used in vitro and ex vivo cell culture systems and will illustrate how these systems will help us to face the challenges imposed by the current SARS-CoV-2 pandemic. 相似文献
79.
Su RJ Zhang XB Li K Yang M Li CK Fok TF James AE Pong H Yuen PM 《British journal of haematology》2002,117(3):735-746
Platelet-derived growth factor (PDGF) is a major mitogen for connective tissue cells. In this study, we investigated the effects and mechanism of PDGF on the ex vivo expansion of cord blood CD34+ cells. Our data demonstrated that among various cytokine combinations of thrombopoietin (TPO), interleukin 1 beta (IL-1beta), IL-3, IL-6 and Flt-3 ligand (Flt-3L), TPO + IL-6 + Flt-3L was most efficient in promoting the expansion of CD34+ cells, CD34+CD38- cells, mixed-lineage colony-forming units (CFU-GEMM) and long-term culture-initiating cells (LTC-IC) by 21.7 +/- 5.00-, 103 +/- 27.9-, 10.7 +/- 7.94- and 6.52 +/- 1.51-fold, respectively, after 12-14 d of culture. The addition of PDGF increased the yield of these early progenitors by 45.0%, 66.5%, 45.1% and 79.8% respectively. More significantly, PDGF enhanced the engraftment of human CD45+ cells and their myeloid subsets (CD33+, CD14+ cells) in non-obese diabetic (NOD)/severe-combined immunodeficient (SCID) mice. The expression of PDGF receptor (PDGFR)-beta was not detectable in fresh CD34+ cells but was upregulated after culture for 3 d. PDGF also enhanced the development of adherent cells/clusters that expressed the endothelial markers VE-cadherin and CD31. These findings suggest that PDGF is an effective cytokine for the ex vivo expansion of early stem and progenitor cells. The mechanism could be mediated by PDGFR-beta on committed CD34+ progenitor cells and/or secondary to the stimulation of autologous, stromal feeder cells. 相似文献