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181.
Liujun Zhao Guoqing Li Jiayong Liu Gregory M. Benedict Nabil A. Ebraheim Weihu Ma Shaohua Sun Rongming Xu Chaoyue Ruan 《European spine journal》2014,23(10):2175-2181
Objective
To explore the best entry point and trajectory of anterior cervical transpedicular screws in the lower cervical spine by radiological studies, and provide reference for clinical application.Methods
Fifty patients were scanned by computed tomography and confirmed no obvious defect of the cervical spine. On horizontal axis, camber angle (α) and axial length (AL) were measured from C3 to C7. On sagittal view, the cranial or caudal angle (β) and sagittal length (SL) were also measured from C3 to C7. On the sagittal and horizontal planes vertebrae were respectively divided into four areas, ordered 1–4, on the anterior side of the pedicle. The areas and angles of pedicle intersect into the vertebral body were recorded. We inserted six anterior pedicle screws into the lower cervical spine of three patients by this technique.Results
On transverse plane, camber angle (α) of C3–C5 increased gradually, while it decreased from C5 to C7. On sagittal view, C3 and C4 pedicles showed cranial tilting, while C5 to C7 were caudally tilted. AL and SL values increased gradually from C3 to C7. The number of the intersections of C3–C7 in each area was also different. Six pedicle screws of three cases were inserted into the lower cervical spine with proper placement and no complications.Conclusion
Anterior transpedicular screw (ATPS) is a theoretically feasible option for internal fixation. The technique described in this paper was subsequently used in three patients without complication. Future improvement of ATPS insertion remains necessary for this technically demanding procedure. 相似文献182.
In plant−virus interactions, the plant immune system and virulence strategies are under constant pressure for dominance, and the balance of these opposing selection pressures can result in disease or resistance. The naturally evolving plant antiviral immune defense consists of a multilayered perception system represented by pattern recognition receptors (PRR) and resistance (R) proteins similarly to the nonviral pathogen innate defenses. Another layer of antiviral immunity, signaling via a cell surface receptor-like kinase to inhibit host and viral mRNA translation, has been identified as a virulence target of the geminivirus nuclear shuttle protein. The Geminiviridae family comprises broad-host range viruses that cause devastating plant diseases in a large variety of relevant crops and vegetables and hence have evolved a repertoire of immune-suppressing functions. In this review, we discuss the primary layers of the receptor-mediated antiviral immune system, focusing on the mechanisms developed by geminiviruses to overcome plant immunity. 相似文献
183.
Aimin Jiang Na Liu Shuheng Bai Jingjing Wang Huan Gao Xiaoqiang Zheng Xiao Fu Mengdi Ren Xiaoni Zhang Tao Tian Zhiping Ruan Xuan Liang Yu Yao 《Journal of thoracic disease》2021,13(2):720
BackgroundLung adenocarcinoma (LUAD) is the most predominant pathological subtype of lung cancer, accounting for 40–70% of all lung cancer cases. Although significant improvements have been made in the screening, diagnosis, and precise management in recent years, the prognosis of LUAD remains bleak. This study aimed to investigate the prognostic significance of autophagy-related long non-coding RNAs (lncRNAs) and construct an autophagy-related lncRNA prognostic model in LUAD.MethodsThe gene expression data of LUAD patients were obtained from The Cancer Genome Atlas (TCGA) database. All autophagy-related genes were downloaded from the Human Autophagy Database (HADb). Spearman’s correlation test was exploited to identify potential autophagy-related lncRNAs. The multivariate Cox regression analysis was used to construct the prognostic signature, which divided LUAD patients into high-risk and low-risk groups. Subsequently, the receiver operating characteristic (ROC) curves were generated to assess the predictive ability of this prognostic model for overall survival (OS) in these individuals. Then, the Gene set enrichment analysis (GSEA) was conducted to execute pathway enrichment analysis. Finally, a multidimensional validation was exploited to verify our findings.ResultsA total of 1,144 autophagy-related lncRNAs were identified to construct the co-expression network via Spearman’s correlation test (|R2| >0.4 and P≤0.001). Ultimately, a 16 autophagy-related lncRNAs prognostic model was constructed, and the area under the ROC curve (AUC) was 0.775. The results of GSEA enrichment analysis showed that the genes in the high-risk group were mainly enriched in cell cycle and p53 signaling pathways. The results of the multidimensional database validation indicated that the expression level of BIRC5 was significantly correlated with the expression level of TMPO-AS1. Furthermore, both TMPO-AS1 and BIRC5 had a higher expression level in LUAD samples. LUAD patients with high expression levels of TMPO-AS1 and BIRC5 were correlated with advanced disease stage and poor OS.ConclusionsIn summary, our results suggested that the prognostic signature of the 16 autophagy-related lncRNAs has significant prognostic value for LUAD patients. Furthermore, TMPO-AS1 and BIRC5 are potential predictors and therapeutic targets in these individuals. 相似文献
184.
Synthesis and Evaluation of a CBZ‐AAN‐Dox Prodrug and its in vitro Effects on SiHa Cervical Cancer Cells Under Hypoxic Conditions
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Hongyuan Chen Xiao Liu Eric S. Clayman Fangyuan Shao Manshan Xiao Xuyan Tian Wuyu Fu Caiyun Zhang Bibo Ruan Pengjun Zhou Zhong Liu Yifei Wang Wen Rui 《Chemical biology & drug design》2015,86(4):589-598
Although doxorubicin (Dox) is widely used in clinical treatment for solid tumors, it causes many side‐effects such as heart and kidney damage, bone marrow suppression, and drug resistance. Legumain is a lysosomal protease that is elevated and associated with an invasive and metastatic phenotype in a number of solid tumors. In this study, we designed and synthesized a Dox prodrug, N‐benzyloxycarbonyl‐Ala‐Ala‐Asn‐Doxorubicin (CBZ‐AAN‐Dox), with 94% purity. Single substrate kinetic assays demonstrated hLegumain‐specific enzymatic cleavage and activation of the prodrug in vitro, and this enzymatic cleavage of the prodrug substrate was more sensitive in acidic conditions, releasing more than 70% of Dox after 24 h. Treatment of tumor cells with our prodrug demonstrated a much higher IC50 value, significantly enhanced uptake of the prodrug, and considerably less cellular toxicity compared to Dox treatment alone. Our study presents a novel prodrug, CBZ‐AAN‐Dox, to potentially increase both the safety and efficacy of clinical treatment of tumors by exploiting the tumor's innate expression of legumain. 相似文献
185.
Yan-Dong Li Shu-Wen Zhu Jiang-Ping Yu Rong-Wei Ruan Zhao Cui Yi-Ting Li Mei-Chao Lv Huo-Gen Wang Ming Chen Chao-Hui Jin Shi Wang 《Digestive and liver disease》2021,53(2):216-223
BackgroundObservation of the entire stomach during esophagogastroduodenoscopy (EGD) is important; however, there is a lack of effective evaluation tools.AimsTo develop an artificial intelligence (AI)-assisted EGD system able to automatically monitor blind spots in real-time.MethodsAn AI-based system, called the Intelligent Detection Endoscopic Assistant (IDEA), was developed using a deep convolutional neural network (DCNN) and long short-term memory (LSTM). The performance of IDEA for recognition of gastric sites in images and videos was evaluated. Primary outcomes included diagnostic accuracy, sensitivity, and specificity.ResultsA total of 170,297 images and 5779 endoscopic videos were collected to develop the system. As the test group, 3100 EGD images were acquired to evaluate the performance of DCNN in recognition of gastric sites in images. The sensitivity, specificity, and accuracy of DCNN were determined as 97.18%,99.91%, and 99.83%, respectively. To assess the performance of IDEA in recognition of gastric sites in EGD videos, 129 videos were used as the test group. The sensitivity, specificity, and accuracy of IDEA were 96.29%,93.32%, and 95.30%, respectively.ConclusionsIDEA achieved high accuracy for recognition of gastric sites in real-time. The system can be applied as a powerful assistant tool for monitoring blind spots during EGD. 相似文献
186.
Yanping Ruan Xiangyu Liu Haogang Zhu Yijie Lu Xiaowei Liu Jiancheng Han Lin Sun Ye Zhang Xiaoyan Gu Ying Zhao Lei Li Suzhen Ran Jingli Chen Qiong Yu Yan Xu Hongmei Xia Yihua He 《Congenital heart disease》2021,16(6):529-549
Background: Current studies have confirmed that fetal congenital heart diseases (CHDs) are caused by various factors. However, the quantitative risk of CHD is not clear given the combined effects of multiple factors. Objective: This cross-sectional study aimed to detect associated factors of fetal CHD using a Bayesian network in a large sample and quantitatively analyze relative risk ratios (RRs). Methods: Pregnant women who underwent fetal echocardiography (N = 16,086 including 3,312 with CHD fetuses) were analyzed. Twenty-six maternal and fetal factors were obtained. A Bayesian network is constructed based on all variables through structural learning and parameter learning methods to find the environmental factors that directly and indirectly associated with outcome, and the probability of fetal CHD in the two groups is predicted through a junction tree reasoning algorithm, so as to obtain RR for fetal CHD under different exposure factor combinations. Taking into account the effect of gestational week on the accuracy of model prediction, we conducted sensitivity analysis on gestational week groups. Results: The single-factor analysis showed that the RRs for the numbers of births, spontaneous abortions, and parental smoking were 1.50, 1.38, and 1.11 (P < 0.001), respectively. The risk gradually increased with the synergistic effect of ranging from one to more environmental factors above. The risk was higher among subjects with five synergistic factors, including the number of births, upper respiratory tract infection during early pregnancy, anemia, and mental stress as well as a history of spontaneous abortions or parental smoking, than in those with less than 5 factors (RR = 2.62 or 2.28, P < 0.001). This result was consistent across the participants grouped by GWs. Conclusion: We identified six factors that were directly associated with fetal CHD. A higher number of these factors led to a higher risk of CHD. These findings suggest that it is important to strengthen healthcare and prenatal counseling for women with these factors. 相似文献
187.
Tian-Jie Qin Xin-Han Zhao Jun Yun Ling-Xiao Zhang Zhi-Ping Ruan Bo-Rong Pan 《World journal of gastroenterology : WJG》2008,14(33)
AIM:To evaluate the efficacy and safety of gemcitabine-oxaliplatin(GEMOX)cornbined with huachansu(cinobufagin)injection treatment in patients with locally advanced or metastatic gallbladder carcinoma(GBC),and to assess the quality of life(QOL)of such patients.METHODS:Twenty-five patients with locally advanced or metastatic GBC were treated with intravenous gemcitabine(1000 mg/m2)over 30 min on days 1 and 8,2 h infusion of oxaliplatin(120 mg/m2)on day 1,and 2-3 h infusion of huachansu(20 mL/m2)on days-3-11,every 3-4 wk.Treatment was continued until occurrence of unacceptable toxicity or disease progression.QOL of patients was assessed by the EORTC QLQ-C30 at baseline,at the end of the first,third and sixth chemotherapy cycles,and 1 mo after the treatment.RESULTS:Among the 25 patients with a median age of 64 years(range 42-78 years),23 were evaluable in the study.A total of 137 cycles of therapy were performed and the median cycle was 5(range 1-8)per patient.Out of the 23 patients whose response could be evaluated,8 partial responses(PR)were observed(34.8%),while 7 patients(30.4%)demonstrated a stable disease(SD).The disease control rate was 65.2%.Progression of cancer was observed in 8(34.8%)patients.The median progression-free and overall survival time was 5.8 mo(95% CI:4.5-7.1 mo)and 10.5 mo,respectively.The therapy was well tolerated,with moderate myelosuppression as the main toxicity.Anemia grade 2 was seen in 16.0%,neutropenia grade 3 in 8.0% and thrombocytopenia grade 3 in 24.0% of patients,respectively.Non-hematologic toxicity ranged from mild to moderate.No death occurred due to toxicity.The QOL of patients was improved after chemotherapy,and the scores of QOL were increased by 10 t0 20 points.CONCLUSION:GEMOX combined with huachansu(cinobufagin)injection is well tolerated,effective,thus ireproving the QOL of patients with advanced GBC.(C)2008 The WJG Press.All rights reserved. 相似文献
188.
Targeted deletion of histidine decarboxylase gene in mice increases bone formation and protects against ovariectomy-induced bone loss 总被引:7,自引:0,他引:7
Fitzpatrick LA Buzas E Gagne TJ Nagy A Horvath C Ferencz V Mester A Kari B Ruan M Falus A Barsony J 《Proceedings of the National Academy of Sciences of the United States of America》2003,100(10):6027-6032
Targeted disruption of the histidine decarboxylase gene (HDC(-/-)), the only histamine-synthesizing enzyme, led to a histamine-deficient mice characterized by undetectable tissue histamine levels, impaired gastric acid secretion, impaired passive cutaneous anaphylaxis, and decreased mast cell degranulation. We used this model to study the role of histamine in bone physiology. Compared with WT mice, HDC(-/-) mice receiving a histamine-free diet had increased bone mineral density, increased cortical bone thickness, higher rate of bone formation, and a marked decrease in osteoclasts. After ovariectomy, cortical and trabecular bone loss was reduced by 50% in HDC(-/-) mice compared with WT. Histamine deficiency protected the skeleton from osteoporosis directly, by inhibiting osteoclastogenesis, and indirectly, by increasing calcitriol synthesis. Quantitative RT-PCR showed elevated 25-hydroxyvitamin D-1alpha-hydroxylase and markedly decreased 25-hydroxyvitamin D-24-hydroxylase mRNA levels. Serum parameters confirming this indirect effect included elevated calcitriol, phosphorus, alkaline phosphatase, and receptor activator of NF-kappaB ligand concentrations, and suppressed parathyroid hormone concentrations in HDC(-/-) mice compared with WT mice. After ovariectomy, histamine-deficient mice were protected from bone loss by the combination of increased bone formation and reduced bone resorption. 相似文献
189.
190.
高层次人才的引进可以迅速增强高校科研实力,缩短培养时间,但引进成本高昂,因此,必须加强高层次科研人才引进时的科学评价.本文阐述了评价高层次科研人才的主要指标,结合高层次科研人才的年龄、科研年龄等提出了科研业绩与人才未来科研贡献预测的定量评价模型,并对评价模型进行了运用说明. 相似文献