检索结果-南通市图书馆

SYNTHESIS OF DIAZA CROWN ETHER CHIRAL LIQUID CRYSTAL

在线全文

学校读者我要写书评

暂无评论

Chinese Chemical Letters 1992年第10期3卷 775-778页

作者： Ming Gui XIE Jun QIN Zi Lun hu hua Ming ZHAO Department of Chemistry Sichuan UniversityChengdu 610064.

A chiral liquid crystal crown ether containing diaza-18-crown-6 was synthesized with the help of CPK atomic model and in the meantime a nonchiral liquid crystal crown ether of alike structure was also synthesized for comparison, indicating that only the former was asymmetric. The present work represents the first attempt of the investigation in chiral liquid crystal crown ether, thus providing basis for further research into problems as such.

关键词： KBr IR CDC SH ppm SYNTHESIS OF DIAZA CROWN ETHER CHIRAL LIQUID CRYSTAL

Five-year outcomes of immediate implant placement for mandibular molars with and without chronic apical periodontitis:A retrospective study

在线全文

学校读者我要写书评

暂无评论

World Journal of Clinical Cases 2023年第22期11卷 5224-5235页

作者： hua Yang Dan Luo Mu-Jie Yuan Jian-Jun Yang Da-Shan Wang Department of Oral and Maxillofacial Surgery The Affiliated Hospital of Qingdao UniversityQingdao 266003Shandong ProvinceChina School of Stomatology Qingdao UniversityQingdao 266003Shandong ProvinceChina Department of Oral Implantology The Affiliated Hospital of Qingdao UniversityQingdao 266003Shandong ProvinceChina

BACKGROUND Most physicians consider molars with chronic apical periodontitis(CAP)lesions as contraindications for immediate implant placement.At the patient’s request,we perform immediate implant placement of the mandibular molars with CAP in clinical practice.AIM To retrospectively analyze and compare the 5-year outcomes of immediate implant placement of the mandibular molars with CAP and those without obvious inflammation.METHODS The clinical data of patients with immediate implant placement of the mandibular molars in the Department of Oral and Maxillofacial Surgery,the Affiliated Hospital of Qingdao University,from June 2015 to June 2017 were collected.The patients were divided into CAP(n=52)and no-CAP(n=45)groups.Changes in bone mineral density and bone mass around implants were analyzed 5 years after implant restoration.RESULTS At 5 years after implantation,the peri-implant bone mineral density was 528.2±78.8 Hounsfield unit(hu)in the CAP group and 562.6±82.9 hu in the no-CAP group(P=0.126).Marginal bone resorption around implants did not differ significantly between the two groups,including buccal(P=0.268)or lingual(P=0.526)resorption in the vertical direction or buccal(P=0.428)or lingual(P=0.560)resorption in the horizontal direction.Changes in the peri-implant jump space did not differ significantly between the two groups,including the buccal(P=0.247)or lingual(P=0.604)space in the vertical direction or buccal(P=0.527)or lingual(P=0.707)space in the horizontal direction.The gray value of cone-beam computed tomography measured using Image J software can reflect the bone mineral density.In the CAP area,the gray values of the bone tissue immediately and 5 years after implant placement differed significantly from those of the surrounding bone tissue(P<0.01).CONCLUSION The results of this study suggest that immediate implant placement of the mandibular molars with CAP can achieve satisfactory 5-year clinical results,without significant differences in the complications,survival rate,or bone tissue condition fr

关键词： Molar Chronic apical periodontitis Dental implantation Bone density Treatment outcome Retrospective study

DNA混合池技术在遗传及分子流行病学中的应用进展

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

中华流行病学杂志 2010年第7期31卷 820-822页

作者：胡洋胡永华北京大学基础医学院 100191 北京大学公共卫生学院 100191

许多慢性非传染性疾病的病因机制复杂，其发病与环境暴露因素有关，也与遗传易感性及交互作用关系密切。在应用遗传及分子流行病学对复杂疾病的病因研究中，常常需要应用多种现代分子生物学技术对样本进行检测。其中反转录一聚合酶链反... 详细信息

许多慢性非传染性疾病的病因机制复杂，其发病与环境暴露因素有关，也与遗传易感性及交互作用关系密切。在应用遗传及分子流行病学对复杂疾病的病因研究中，常常需要应用多种现代分子生物学技术对样本进行检测。其中反转录一聚合酶链反应（R1=PCR）、微卫星（micro satellite，MS）、等位基因特异性杂交（allele—specific hybridization，ASH）等方法被广泛应用。

关键词：遗传流行病学分子流行病学 DNA混合池

Evaluation of controlled attenuation parameter in assessing hepatic steatosis in patients with autoimmune liver diseases

在线全文

学校读者我要写书评

暂无评论

World Journal of Gastroenterology 2021年第1期27卷 80-91页

作者： Xi-Xi Ni Min Lian hui-Min Wu Xiao-yun Li Li Sheng Han Bao Qi Miao Xiao Xiao Can-Jie Guo Hai Li Xiong Ma Jing hua Department of Gastroenterology and Hepatology Renji HospitalSchool of MedicineShanghai Jiao Tong UniversityShanghai Institute of Digestive DiseaseShanghai 200127China Department of Gastroenterology and Hepatology Renji HospitalSchool of MedicineShanghai Jiao Tong UniversityShanghai 200127China School of Medicine Shanghai Jiao Tong UniversityShanghai Cancer InstituteShanghai Institute of Digestive DiseaseShanghai 200127China School of Medicine Shanghai Jiao Tong UniversityShanghai Institute of Digestive DiseaseShanghai 200127China Department of Gastroenterology Renji HospitalShanghai Jiao Tong University School of MedicineShanghai 200127China Department of Gastroenterology Renji HospitalSchool of MedicineShanghai Jiao Tong UniversityShanghai Institute of Digestive DiseaseShanghai 200001China

BACKGROUND Hepatic steatosis commonly occurs in some chronic liver diseases and may affect disease progression.AIM To investigate the performance of controlled attenuation parameter(CAP)for the diagnosis of hepatic steatosis in patients with autoimmune liver diseases(AILDs).METHODS Patients who were suspected of having AILDs and underwent liver biopsy were consistently enrolled.Liver stiffness measurement(LSM)and CAP were performed by transient elastography.The area under the receiver operating characteristic(AUROC)curve was used to evaluate the performance of CAP for diagnosing hepatic steatosis compared with biopsy.RESULTS Among 190 patients with biopsy-proven hepatic steatosis,69 were diagnosed with autoimmune hepatitis(AIH),18 with primary biliary cholangitis(PBC),and 27 with AIH-PBC overlap syndrome.The AUROCs of CAP for the diagnosis of steatosis in AILDS were 0.878(0.791-0.965)for S1,0.764(0.676-0.853)for S2,and 0.821(0.716-0.926)for S3.The CAP value was significantly related to hepatic steatosis grade(P<0.001).Among 69 patients with AIH,the median CAP score was 205.63±47.36 dB/m for S0,258.41±42.83 dB/m for S1,293.00±37.18 dB/m for S2,and 313.60±27.89 dB/m for S3.Compared with patients with nonalcoholic fatty liver disease(NAFLD)presenting with autoimmune markers,patients with AIH concomitant with NAFLD were much older and had higher serum IgG levels and LSM values.CONCLUSION CAP can be used as a noninvasive diagnostic method to evaluate hepatic steatosis in patients with AILDs.Determination of LSM combined with CAP may help to identify patients with AIH concomitant with NAFLD from those with NAFLD with autoimmune phenomena.

关键词： Controlled attenuation parameter Hepatic steatosis Autoimmune liver diseases Nonalcoholic fatty liver disease Liver stiffness measurement Autoimmune hepatitis

超声四维应变成像技术预测冠心病患者PCI术后左室心肌功能改善的研究

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

东南大学学报（医学版） 2017年第5期36卷 710-716页

作者：李云李华胡劼新疆医科大学附属中医医院心脏超声科新疆乌鲁木齐830000

目的:探讨四维应变成像(four-dimensional strain imaging,4D-SI)技术预测经皮冠状动脉介入(percutaneous coronary intervention,PCI)术冠心病患者左心功能改善的临床价值。方法:选取经冠脉造影诊断为冠心病且成功进行PCI术的患者55例,... 详细信息

目的:探讨四维应变成像(four-dimensional strain imaging,4D-SI)技术预测经皮冠状动脉介入(percutaneous coronary intervention,PCI)术冠心病患者左心功能改善的临床价值。方法:选取经冠脉造影诊断为冠心病且成功进行PCI术的患者55例,以PCI术后6个月较术前左室射血分数(left ventricular ejection fraction,LVEF)改善(ΔLVEF)≥5%将冠心病患者分为左心功能改善组(A组)和未改善组(B组)。分别于PCI术前及术后6个月对各组患者进行常规超声心动图检查,测量左室舒张末期容积(left ventricular end-diastolic volume,LVEDV)、左室收缩末期容积(left ventricular end-systolic volume,LVESV)、LVEF;应用自动功能成像(automated function imaging,AFI)技术测量二维整体峰值纵向应变(two-dimensional global longitudinal peak strain,2D-GLPS);并应用4D-SI技术测得四维整体峰值长轴应变(global longitudinal peak strain,4DGLPS)、环向应变(global circumferential peak strain 4D-GCPS)、面积应变(global area peak strain,4D-GAPS)及径向应变(global radial peak strain,4D-GRPS)参数指标。结果:A组PCI术前及术后6个月2D-GLPS、4DGLPS、4D-GCPS、4D-GAPS和4D-GRPS均明显高于B组(P<0.05)。单参数受试者工作特征曲线(ROC曲线)分析结果显示4D-GLPS的曲线下面积(AUC)较大,为0.944,灵敏度及特异度较高,分别为91.3%、93.8%,截断值为-16.5%;在多参数联合分析中,四维应变参数联合二维应变参数的AUC较大,为0.969,灵敏度及特异度较高,分别为95.7%、90.6%。结论:4D-SI技术能更准确预测冠心病患者PCI术后左室心肌功能的改善,其中4D-GAPS及4D-GCPS能够作为术后左心整体功能改善的独立预测指标。

关键词：冠心病经皮冠状动脉介入术四维应变成像自动功能成像

The positive function of selenium supplementation on reducing nitrate accumulation in hydroponic lettuce(Lactuca sativa L.)

在线全文

学校读者我要写书评

暂无评论

Journal of Integrative Agriculture 2018年第4期17卷 837-846页

作者： LEI Bo BIAN Zhong-hua YANG Qi-chang WANG Jun CHENG Rui-feng LI Kun LIU Wen-ke ZHANG Yi FANG hui TONG yun-xin Key Laboratory of Energy Conservation and Waste Treatment of Agricultural Structures Ministry of Agriculture/Institute of Environment and Sustainable Development in Agriculture Chinese Academy of Agricultural Sciences Nottingham Trent University Brackenhurst Campus

High nitrate(NO3-) in vegetables, especially in leaf vegetables poses threaten to human health. Selenium(Se) is an important element for maintaining human health, and exogenous Se application during vegetable and crop production is an effective way to prevent Se deficiency in human bodies. Exogenous Se shows positive function on plant growth and nutrition uptake under abiotic and/or biotic stresses. However, the influence of exogenous Se on NO3-accumulation in hydroponic vegetables is still not clear. In the present study, hydroponic lettuce plants were subjected to six different concentrations(0, 0.1, 0.5, 5, 10 and 50 μmol L–1) of Se as Na2 Se O3. The effects of Se on NO3-content, plant growth, and photosynthetic capacity of lettuce(Lactuca sativa L.) were investigated. The results showed that exogenous Se positively decreased NO3-content and this effect was concentration-dependent. The lowest NO3-content was obtained under 0.5 μmol L–1 Se treatment. The application of Se enhanced photosynthetic capacity by increasing the photosynthesis rate(Pn), stomatal conductance(Cs) and the transpiration efficiency(Tr) of lettuce. The transportation and assimilation of NO3-and activities of nitrogen metabolism enzymes in lettuce were also analysed. The NO3-efflux in the lettuce roots was markedly increased, but the efflux of NO3-from the root to the shoot was decreased after treated with exogenous Se. Moreover, Se application stimulated NO3-assimilation by enhancing nitrate reductase(NR), nitrite reductase(Ni R), glutamine synthetase(GS) and glutamate synthase enzyme(GOGAT) activities. These results provide direct evidence that exogenous Se shows positive function on decreasing NO3-accumulation via regulating the transport and enhancing activities of nitrogen metabolism enzyme in lettuce. We suggested that 0.5 μmol L–1 Se can be used to reduce NO3-content and increase hydroponic lettuce yield.

关键词： selenium NO_3^- nitrogen metabolism enzyme SIET photosynthetic performance lettuce

Genomic Evolution and Variation of SARS-CoV-2 in the Early Phase of COVID-19 Pandemic in Guangdong Province,China

在线全文

学校读者我要写书评

暂无评论

Current Medical Science 2021年第2期41卷 228-235页

作者： Bai-sheng LI Zhen-cui LI Yao hu Li-jun LIANG Li-rong ZOU Qian-fang GUO Zhong-hua ZHENG Jian-xiang YU Tie SONG Jie WU Guangdong Provincial Center for Disease Control and Prevention Guangzhou 510000China Guangdong Workstation for Emerging Infectious Disease Control and Prevention Chinese Academy of Medical SciencesGuangzhou 510000China Southern Medical University Guangzhou 510000China

Severe acute respiratory syndrome coronavirus 2(SARS-CoV-2)with unknown origin spread rapidly to 222 countries,areas or territories.To investigate the genomic evolution and variation in the early phase of COVID-19 pandemic in Guangdong,60 specimens of SARS-CoV-2 were used to perform whole genome sequencing,and genomics,amino acid variation and Spike protein structure modeling analyses.Phylogenetic analysis suggested that the early variation in the SARS-CoV-2 genome was still intra-species,with no evolution to other coronaviruses.There were one to seven nucleotide variations(SNVs)in each genome and all SNVs were distributed in various fragments of the genome.The Spike protein bound with human receptor,an amino acid salt bridge and a potential furin cleavage site were found in the SARS-CoV-2 using molecular modeling.Our study clarifed the characteristics of SARS-CoV-2 genomic evolution,variation and Spike protein structure in the early phase of local cases in Guangdong,which provided reference for generating prevention and control strategies and tracing the source of new outbreaks.

关键词： severe acute respiratory syndrome coronavirus 2(SARS-CoV-2) spike protein genomic evolution

Modeling the Potential Geographic Distribution of Black Pepper(Piper nigrum)in Asia Using GIS Tools

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Integrative Agriculture 2012年第4期11卷 593-599页

作者： HAO Chao-yun FAN Rui Milton Cezar Ribeiro[ TAN Le-he WU hua-song YANG Jian-feng ZHENG Wei-quan YU huan Spice and Beverage Research Institute Chinese Academy of Tropical Agricultural Sciences/Key Laboratory of Genetic Resources Utilization of Spice and Beverage Crops Ministry of Agriculture/Hainan Provincial Key Laboratory of Genetic Improvement and Quality Regulation for Tropical Spice and Beverage Crops Wanning 571533 P.R.China Ecological Departament University of Sao Paulo Sao Paulo 05513-970 S.P.Brazil

Known as the ＂king of spices＂,black pepper（Piper nigrum）,a perennial crop of the tropics,is economically the most important and the most widely used spice crop in the world.To understand its suitable bioclimatic distribution,maximum entropy based on ecological niche modeling was used to model the bioclimatic niches of the species in its Asian range.Based on known occurrences,bioclimatic areas with higher probabilities are mainly located in the eastern and western coasts of the Indian Peninsula,the east of Sumatra Island,some areas in the Malay Archipelago,and the southeast coastal areas of China.Some undocumented places were also predicted as suitable areas.According to the jackknife procedure,the minimum temperature of the coldest month,the mean monthly temperature range,and the precipitation of the wettest month were identified as highly effective factors in the distribution of black pepper and could possibly account for the crop＇s distribution pattern.Such climatic requirements inhibited this species from dispersing and gaining a larger geographical range.

关键词： Piper ngirum ENM bioclimatic distribution Maxent

在线全文

学校读者我要写书评

暂无评论

HPLC法同时测定姜桂颗粒中5种成分

中成药 2023年第4期45卷 1086-1089页

作者：胡北高欢陈莹许子华北部战区总医院辽宁沈阳110000

目的建立HPLC法同时测定姜桂颗粒中葛根素、甘草苷、肉桂酸、桂皮醛、甘草酸铵的含量。方法该药物60%甲醇提取液的分析采用Agilent ZORBAX SB-C_(18)色谱柱(4.6 mm×250 mm,5μm);流动相乙腈-0.1%磷酸,梯度洗脱;体积流量1.0 mL/min;柱... 详细信息

目的建立HPLC法同时测定姜桂颗粒中葛根素、甘草苷、肉桂酸、桂皮醛、甘草酸铵的含量。方法该药物60%甲醇提取液的分析采用Agilent ZORBAX SB-C_(18)色谱柱(4.6 mm×250 mm,5μm);流动相乙腈-0.1%磷酸,梯度洗脱;体积流量1.0 mL/min;柱温30℃;检测波长265 nm。结果5种成分在各自范围内线性关系良好(r>0.9990),平均加样回收率98.84%~100.22%,RSD 1.55%~2.70%。结论该方法稳定、快速、重复性好,可用于姜桂颗粒的质量控制。

关键词：姜桂颗粒葛根素甘草苷肉桂酸桂皮醛甘草酸铵 HPLC