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1.
AIM: To explore the photopic pupil size behavior in myopic children undergoing overnight orthokeratology (ortho-k) over 1-year period and its effects on the axial elongation. METHODS: A total of 202 Chinese myopic children were enrolled in this prospective clinical trial. Ninety-five subjects in ortho-k group and eighty-eight subjects in spectacle group completed the 1-year study. Axial length (AL) was measured before enrollment and every 6mo after the start of ortho-k. The photopic pupil diameter (PPD) was determined using the Pentacam AXL and measured in an examination room with lighting of 300-310 Lx. Stepwise multiple linear regression analysis was used to identify variables contribution to axial elongation. RESULTS: Compared with spectacle group, the average 1-year axial elongation was significantly slower in the ortho-k group (0.25±0.27 vs 0.44±0.23 mm, P<0.0001). In ortho-k group, PPDs significantly decreased from 4.21±0.62 mm to 3.94±0.53 mm after 1mo of lens wear (P=0.001, Bonferroni correction) and the change lasts for 3-month visit. No significantly change during the other follow-up visits was found (P>0.05, Bonferroni correction). The 4.81 mm PPD may be a possible cutoff point in the ortho-k group. Subjects with PPD below or equal to 4.81 mm tended to have smaller axial elongation compared to subjects with PPD above 4.81 mm after 1-year period (t=-3.09, P=0.003). In ortho-k group, univariate analyses indicated that those with older age, greater degree of myopia, longer AL, smaller baseline PPD (PPDbaseline) experienced a smaller change in AL. In multivariate analyses, older age, greater AL and smaller PPDbaseline were associated with smaller increases in AL. In spectacle group, PPD tended to be stable (P>0.05, Bonferroni correction) and did not affect axial growth. CONCLUSION: PPDs experience significantly decreases at 1-month and 3-month ortho-k treatment. Children with smaller PPD tend to experience slower axial elongation and may benefit more from ortho-k.  相似文献   
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Parkinson's disease(PD) is one of the most common neurodegenerative diseases,affecting individuals especially over 60 years of age.In the next three decades,more than 12 million people will suffer from PD worldwide(Rocca,2018).The characteristic symptoms of PD begin as a movement disorder including bradykinesia,resting tremor,rigidity,and postural instability.  相似文献   
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Objective:Pancreatic ductal adenocarcinoma(PDAC)is a deadly malignancy,due in large part to its resistance to conventional therapies,including radiotherapy(RT).Despite RT exerting a modest antitumor response,it has also been shown to promote an immunosuppressive tumor microenvironment.Previous studies demonstrated that focal adhesion kinase inhibitors(FAKi)in clinical development inhibit the infiltration of suppressive myeloid cells and T regulatory(T regs)cells,and subsequently enhance effector T cell infiltration.FAK inhibitors in clinical development have not been investigated in combination with RT in preclinical murine models or clinical studies.Thus,we investigated the impact of FAK inhibition on RT,its potential as an RT sensitizer and immunomodulator in a murine model of PDAC.Methods:We used a syngeneic orthotopic murine model to study the effect of FAKi on hypofractionated RT.Results:In this study we showed that IN10018,a small molecular FAKi,enhanced antitumor response to RT.Antitumor activity of the combination of FAKi and RT is T cell dependent.FAKi in combination with RT enhanced CD8+T cell infiltration significantly in comparison to the radiation or FAKi treatment alone(P<0.05).FAKi in combination with radiation inhibited the infiltration of granulocytes but enhanced the infiltration of macrophages and T regs in comparison with the radiation or FAKi treatment alone(P<0.01).Conclusions:These results support the clinical development of FAKi as a radiosensitizer for PDAC and combining FAKi with RT to prime the tumor microenvironment of PDAC for immunotherapy.  相似文献   
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As the most common symptomatic reason to seek medical consultation,pain is a complex experience that has been classified into different categories and stages.In pain processing,noxious stimuli may activate the anterior cingulate cortex(ACC).But the function of ACC in the different pain conditions is not well discussed.In this review,we elaborate the commonalities and differences from accumulated evidence by a variety of pain assays for physiological pain and pathological pain including inflammatory pain,neuropathic pain,and cancer pain in the ACC,and discuss the cellular receptors and signaling molecules from animal studies.We further summarize the ACC as a new central neuromodulation target for invasive and non-invasive stimulation techniques in clinical pain management.The comprehensive understanding of pain processing in the ACC may lead to bridging the gap in translational research between basic and clinical studies and to develop new therapies.  相似文献   
6.
AIM: To evaluate urine β2-microglobulin(β2-M), retinol-binding protein(RBP) excretion, and renal impairment with adefovir dipivoxil(ADV) for chronic hepatitis B. METHODS: We enrolled 165 patients with chronic hepatitis B infection who were treated with ADV monotherapy(n = 90) or ADV plus lamivudine combination therapy(n = 75). An additional 165 chronic hepatitis B patients treated with entecavir were recruited as controls. We detected serum creatinine, urine β2-M, and RBP levels, and estimated the glomerular filtration rate(e GFR) at the initiation of antiviral therapy and every 6 mo for a period of five years. RESULTS: Urine β2-M abnormalities were observed in patients during the first(n = 3), second(n = 7), third(n = 11), fourth(n = 16), and fifth(n = 21) year of ADV treatment. Urinary RBP abnormalities were observed in patients during the first(n = 2), second(n = 8), third(n = 12), fourth(n = 15), and fifth(n = 22) year of ADV treatment. e GFR decreased 20%-30% from baseline in 20 patients, 30%-50% in 12 patients, and > 50% in 3 patients during the five years of treatment. Further analysis indicated that decreases in e GFR of ≥ 30% relative to the baseline level correlated significantly with urine RBP and β2-M abnormalities. In contrast, both serum creatinine and e GFR remained stable in patients treated with entecavir, and only one of these patients developed a urine β2-M abnormality, and two developed urine RBP abnormalities during the five years of treatment. CONCLUSION: Urine RBP and β2-M are biomarkers of renal injury during long-term ADV treatment for chronic hepatitis B, and indicate when treatment should be switched to entecavir.  相似文献   
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As orthodontic appliances can corrode with time in the oral environment, the aim of this study was to compare the release of metal ions from new and recycled brackets immersed in buffers of different pH values over a 48 week period. To simulate commercial recycling, the stainless steel brackets were divided into two groups: new and recycled. The bases of the latter were coated with adhesive and the brackets were heat treated before being immersed in the test solution for 48 weeks. The release of nickel, chromium, iron, copper, cobalt and manganese ions was analysed by atomic absorption spectrophotometry. Differences were compared using one-way analysis of variance. The results showed that recycled brackets released more ions than new brackets (P < 0.05). Brackets immersed in solutions of pH 4 released more ions than those immersed in solutions of pH 7, and the total amount of ions released increased with time over the 48 week period (P < 0.05). This study demonstrates that both new and recycled brackets will corrode in the oral environment. To avoid clinical side-effects, metal brackets should be made more resistant to corrosion, and recycled brackets should not be used.  相似文献   
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目的 介绍自行研制的带控制阀种植牙手术骨粉收集器,并观察其临床应用效果.方法 选取2008年5月至2009年10月38例牙种植患者,应用自制的骨粉收集器收集种植窝制备时产生的骨碎屑,并将其用于修复种植体周围骨缺损,其中开窗式骨缺损29处,唇颊(舌)侧种植体颈部角形缺损23处.结果 所有病例术后均无创口感染及裂开,原缺损处局部形态饱满,牙龈无明显退缩,X线片示种植体与周围牙槽骨形成良好的骨结合.结论 应用自制骨粉收集器收集的骨粉修复种植体周围小型骨缺损效果良好,使用方便,具有良好的应用前景.
Abstract:
Objective To introduce a self-developed bone collector designed by the authors and evaluate its effect in clinical application. Methods A self-developed bone collector was used in 38 patients who underwent the dental implant operation from May 2008 to October 2009. During the operation the bone particles were harvested, which was used for the reconstruction of the bone defects around the implant simultaneously. The defects were fenestrate in 29 regions and triangle in 23 regions on buccal or lingual side of the dental implants. Results All cases had no surgical wound infection and dehiscence 7-10 days after operation. Three to six months after implantation, the X-ray showed that all the dental implants had perfect osseointergration and the alveolar bone were successfully augmented. Conclusions Bone debris harvested by self-developed bone collector could repair small peri-implant bone defects, which is simple to use in clinic.  相似文献   
10.
目的 探讨雷帕霉素(rapamycin)与顺铂(cisplatin)联合使用对趋化因子CCL19调节头颈鳞状细胞癌细胞活性的影响.方法 应用甲基噻唑基四唑(MTT)法及流式细胞仪检测顺铂及雷帕霉素对CCL19诱导后人头颈鳞状细胞癌淋巴结转移细胞系(PCI-4B、PCI-37B)生长抑制作用、细胞凋亡作用和细胞周期变化.使用Calcusyn软件计算两种药物(浓度比为80:1)联合使用时的剂量效应参数及联合指数(combination index,CI),使用SPSS 11.0软件包进行统计分析.结果 顺铂及雷帕霉素可以分别提高CCL19作用后细胞的生长抑制率(CCL19+顺铂作用后两细胞系的生长抑制率为21.22%±2.68%和22.76%±2.79%,CCL19+雷帕霉素作用后为19.46%±2.54%和20.6%±4.38%)、细胞G1期比例(CCL19+顺铂作用后两细胞系的G1期比例为72.14%±2.66%和76.39%±1.45%,CCL19+雷帕霉素作用后为75.26%±5.92%和74.00%±1.51%)和凋亡率(CCL19+顺铂作用后两细胞系的凋亡率9.59%±0.86%和7.55%±0.66%,CCL19+雷帕霉素作用后为8.21±1.80%和6.26±0.78%).两种药物浓度比为80:1联合使用时,PCI-4B细胞在半数抑制量(inhibitory concentration 50%,IC50)以下,CI<1,IC75以上CI>1;PCI-37B则在IC75以下CI<1,IC90以上CI>1.结论 顺铂及雷帕霉素均有抑制CCL19对人头颈鳞状细胞癌淋巴结转移细胞的活性调节作用,并且二者联合使用存在协同作用.
Abstract:
Objective To investigate the synergistic effects of rapamycin and cisplatin on head and neck squamous cancer cells regulated by chemokine( C-C motif) ligand 19 (CCL19). Methods The role of rapamycin and cisplatin was detected on cell-cycle and apoptosis in CCL19 induced PCI-4B and PCI-37B cells by methyl thiazolyl tetrazolium (MTT) and flow cytometry(FCM). Dose-effect relationship parameters and combination index(CI) were calculated on the median-effect equation and multiple drug effect equation using computer software CalcuSyn. Statistical analysis was performed by the unpaired student's t-test.Results Rapamycin and cisplatin could respectively increase the growth arrest, the proportion of G1 phase and apoptosis of CCL19 induced cancer cells (P <0. 05 ). Under inhibitory concentration 50% (IC50), CI was less than 1, and in IC75, it was more than 1 in PCI-4B cells. In PCI-37B cells, under IC75, CI was less than 1, and in IC90, it was more than 1. Conclusions Rapamycin and cisplatin can inhibit CCL19-regulated PCI-4B and PCI-37B cells' survival. The two drugs have synergistic effects when used in combination.  相似文献   
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