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991.
BackgroudPhotodynamic therapy (PDT) for the treatment of esophageal cancer was more and more popularly used since it was approved for the treatment of advanced esophageal cancer in 1996. It has been reported to influence the tumor growth and metastasis via a variety of signaling pathways, but its mechanism remains to be further studied. This research studied the effects of ALA-PDT on esophageal carcinoma in vitro and in vivo, discovering its molecular regulating mechanism and the way to enhence the PDT effect.MethodsEca-109 cells were incubated with a medium containing EGFR tyrphostin AG1478 or PI3K inhibitor LY294002, then with ALA, and the cells were irradiated with the laser 6 h later. The cell viability was measured with MTT assay, and the migration ability was detected by transwell experiments 24 h post-ALA-PDT. The gene and protein expression on EGFR/PI3K/AKT signaling pathway was analyzed by realtime PCR and Western blotting respectively. Then, RFP-Eca-109 burdened nude mice model was constructed, and were treated with ALA-PDT when the tumor volume reached 150–350 mm3. The gene and protein expression were analyzed 24 h and 50 days post-ALA-PDT.ResultsOur study showed that ALA-PDT respectively combined with AG1478, LY294002 could synergistically reduce the growth and migration ability of the Eca-109 cells in vitro and significantly down-regulate the protein expression of EGFR/PI3K and PI3K/AKT, meanwhile, significantly down-regulate the gene expression of EGFR when combining with AG1478. Forthermore, ALA-PDT could significantly decrease the tumor growth and metastasis and down-regulate the gene expression of EGFR and the protein expression of EGFR and PI3K in the tumor of mice.ConclusionThis study revealed a molecular mechanism of ALA-PDT and developed a new modality application of therapy, by combining ALA-PDT with small molecular inhibitors, for better effect in the clinical practice of esophageal carcinoma. 相似文献
992.
993.
Adenine nucleotide effect on intraocular pressure: Involvement of the parasympathetic nervous system
Nucleotides are present in the aqueous humor possibly exerting physiological effects on intraocular pressure (IOP). To determine the effect of nucleotides such as ATP and its related derivatives on IOP, New Zealand white rabbits were used. IOP was measured in rabbits treated topically either with saline (control) or with a single dose (10 μg/μL) of adenine nucleotides (ATP, 2-meS-ATP, ATP-γ-S, α,β-meADP, α,β-meATP and β,γ-meATP). Those nucleotides reducing IOP (α,β-meATP and β,γ-meATP) were then tested in concentrations ranging from 1 to 100 μg/μL to obtain the IC50 value. Several antagonists for the P2 and adenosine A1 receptors (all at 10 μg/μL) were assayed 30 min before the application of the hypotensive nucleotide β,γ-meATP. To see whether the nucleotide was acting directly on the structures involved in aqueous humor dynamics or on the autonomic nerves controlling IOP, animal denervation and sympathetic (yohimbine and ICI-118,551 at 10 μg/μL) and parasympathetic (atropine and hexametonium at 10 μg/μL) receptors' antagonists were used 30 min before the instillation of β,γ-meATP. α,β-meATP and β,γ-meATP decreased IOP to 60% of control value (basal IOP = 23.2 ± 1.3 mmHg), with IC50 of 1.59 ± 0.21 μg/μL and 0.56 ± 0.62 μg/μL, which corresponds to 3 mM and 1 mM respectively. Denervation completely abolished the effect of β,γ-meATP. Sympathetic antagonists did not modify the hypotensive effect of β,γ-meATP, but parasympathetic antagonists were able to abolish it. Among the series of adenine nucleotide tested, α,β-meATP and β,γ-meATP presented hypotensive actions on IOP. β,γ-meATP seems to stimulate cholinergic terminals being its final effect the IOP reduction. Therefore, these two nucleotides are interesting pharmacological tools for those pathologies related with high intraocular pressure. 相似文献
994.
995.
目的:通过计算两种用药方式主要麻醉药的用量,核算出经济成本,为指导腹腔镜胆囊切除术(LC)的麻醉用药,降低患者药物费用,提高医疗技术含金量做基础。方法:选择48例美国麻醉师协会(ASA)Ⅰ~Ⅱ级的择期LC患者,随机分为两组,一组麻醉维持异丙酚伍用瑞芬太尼(Pro组)(n=24),一组麻醉维持吸入七氟醚(Sev组)(n=24),两组诱导用药相同,Pro组为异丙酚伍用瑞芬太尼,Sev组为吸入七氟醚,手术终了计算主要麻醉药消耗量并核算成所需费用。结果:两组麻醉后恶心呕吐等并发症比较差异无统计学意义(P>0.05),与Pro组比较,Sev组的维库溴铵用量差异有统计学意义(P<0.05),Sev组所需药物费用较少,差异有统计学意义(P<0.01)。结论:通过两种代表性的用药方式计算出耗药量并核算费用,认为吸入七氟醚组节省费用,值得关注。 相似文献
996.
W.K. Tsui H.D.P. Chua L.K. Cheung 《International journal of oral and maxillofacial surgery》2012,41(11):1427-1438
This systematic review was performed to investigate the usefulness and clinical effectiveness of skeletal anchorage devices to determine the most effective bone anchor system for orthodontic tooth movement. Literature on bone anchorage devices was selected from PubMed and the Cochrane Library from January 1966 to June 2010. 55 publications regarding miniplates, miniscrews, palatal implants and dental implants as orthodontic anchorage were identified for further analysis. All bone anchorage devices were found to have relatively high success rates and demonstrated their ability to provide absolute anchorage for orthodontic tooth movement. Significant tooth movement could be achieved with low morbidities and good patient acceptance. The reported success rates for the four groups of anchorage systems were generally high with slight variability (miniplates 91.4–100%; palatal implants 74–93.3%; miniscrews 61–100%; dental implants 100%). It was concluded that bone anchorage systems can achieve effective orthodontic movement with low morbidities. The success rate is generally high with slight variability between miniplates, palatal implants, miniscrews and dental implants. Owing to the lack of randomized controlled trials, there is no strong evidence to confirm which bone anchor system is the most effective for orthodontic tooth movement. 相似文献
997.
The purpose of this study was to report the characteristics of SIFs after ILSF and discuss its management focusing on pelvic deformation. We retrospectively reviewed all consecutive patients who underwent ILSF for degenerative disc diseases during the period between 2000 and 2017 and were diagnosed as SIF at our institute. The clinical and radiographic data were reviewed on their medical charts. Treatment outcomes for SIF were also investigated. Eight patients (all females) were included in this study. Mean age at SIF diagnosis was 72 years, and the mean follow-up period was 3.8 years (range 1–7 years). SIF developed average 7.5 years (range 1 month−17 years) after the index ILSF. Fracture patterns were unilateral vertical in four, bilateral vertical in three, and horizontal in 1 patient. Unlike patients with unilateral vertical SIF, patients with bilateral vertical or horizontal SIF showed a marked increase of pelvic incidence (PI) by mean 17.0°±5.0° and sagittal vertical axis (SVA) by mean 4.5 ± 2.2 cm, compared to the respective values before the onset of abrupt pain. All patients with unilateral vertical SIF were treated favorably by conservative management, however sacropelvic fixation was inevitable in patients with bilateral vertical or horizontal SIF. Bilateral vertical or horizontal SIF showed marked changes on sagittal radiographic parameters including PI and SVA. Although unilateral vertical SIF has benign courses that responded well to conservative management, bilateral vertical or horizontal SIF is likely to need surgical treatment. Treatment plan should be determined depending on fracture pattern and pelvic deformation. 相似文献
998.
宫颈上皮内瘤变是宫颈癌前病变,基于妇女特有的生理特点,认为宫颈上皮内瘤变属中医“带下病”范畴,并从“虚则生疣”的角度提出该病“根于脾肾,基于正虚,发为湿毒,任带受损”的病因病机。 相似文献
999.
1000.
《Journal of Pharmaceutical Analysis》2020,10(4):385-395
Ziziphi Spinosae Semen (ZSS), a traditional Chinese medicine, is used in clinics for the treatment of insomnia in China and other Asian countries. Herein, we described for the first time a comparative pharmacokinetics study of the six major compounds of ZSS in normal control (NC) and para-chlorophenylalanine (PCPA)-induced insomnia model (IM) rats that were orally administered the aqueous extract of ZSS. An ultra-high-performance liquid chromatography coupled with quadrupole orbitrap mass (UHPLC-Q-Orbitrap-MS) method was developed and validated for the simultaneous determination of coclaurine, magnoflorine, spinosin, 6‴-feruloylspinosin, jujuboside A (JuA), and jujuboside B (JuB) in ZSS in rat plasma. The established approach was successfully applied to a comparative pharmacokinetic study. The systemic exposures of spinosin and 6‴-feruloylspinosin were decreased in the IM group compared to the NC group, while plasma clearance (CL) was significantly increased. The Tmax values of JuA and JuB in IM rats were significantly lower than those in NC rats. The T1/2 of JuA in the IM group was significantly accelerated. The pharmacokinetic parameters of coclaurine and magnoflorine were not evidently affected between the two groups. These results indicate that the pathological state of insomnia altered the plasma pharmacokinetics of spinosin, 6‴-feruloylspinosin, JuA, and JuB in the ZSS aqueous extract, providing an experimental basis for the role of ZSS in insomnia treatment. The comparative pharmacokinetics-based UHPLC-Q-Orbitrap-MS using full-scan mode can therefore provide a reliable and suitable means for the screening of potentially effective substances applied as quality markers of ZSS. 相似文献