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Plant Communications 2020年第2期1卷 88-103页

作者： yi Li Thilo Winzer Zhesi He Ian AGraham Centre for Novel Agricultural Products Department of BiologyUniversity of YorkYork YO105YWUK

Phylogenomic analysis of whole genome sequences of five benzylisoquinoline alkaloid(BIA)-producing species from the Ranunculales and Proteales orders of flowering plants revealed the sequence and timing of evolutionary events leading to the diversification of these compounds.(S)-Reticuline is a pivotal intermediate in the synthesis of many BIAs and our analyses revealed parallel evolution between the two orders,which diverged122 million years ago(MYA).Berberine is present in species across the entire Ranunculales,and we found co-evolution of genes essential for production of the protoberberine *** benzophenanthridine class,which includes the antimicrobial compound sanguinarine,is specific to the Papaveraceae family of Ranunculales,and biosynthetic genes emerged after the split with the Ranunculaceae family110 MYA but before the split of the three Papaveraceae species used in this study at77 *** phthalideisoquinoline noscapine and morphinan class of BIAs are exclusive to the opium poppy *** estimation of paralogous pairs indicates that morphine biosynthesis evolved more recently than 18 MYA in the Papaver *** the preceding 100 million years gene duplication,neofunctionalization and recruitment of additional enzyme classes,combined with gene clustering,gene fusion,and gene amplification,resulted in emergence of medicinally valuable BIAs including morphine and noscapine.

关键词： benzylisoquinoline alkaloids plant genomes gene tree analysis metabolic pathway evolution gene clusters gene fusion

The Dynamics and Bifurcation Control of a Singular Biological Economic Model

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International Journal of Automation and computing 2012年第1期9卷 1-7页

作者： Ning Li Hai-yi Sun Qing-Ling Zhang Institute of Systems Science Northeastern University Shenyang 110819 PRC College of Science Shenyang Jianzhu University Shenyang 110168 PRC

The objective of this paper is to study systematically the dynamics and control strategy of a singular biological economic model that is described by a differential-algebraic equation. It is shown that when the economic profit passes through zero, this model exhibits the transcritical bifurcation, the Hopf bifurcation, and the limit cycle. In particular, the system undergoes the singularity induced bifurcation at the positive equilibrium, which can result in impulse. Then, state feedback controllers closer to the actual control strategies are designed to eliminate the unexpected singularity induced bifurcation and stabilize the positive equilibrium under the positive profit. Finally, numerical simulations verify the results and illustrate the effectiveness of the controllers. Also, the model with positive economic profit is shown numerically to have different dynamics.

关键词： Differential-algebraic equation transcritical bifurcation Hopf bifurcation limit cycle singularity induced bifurcation,bifurcation control.

Specific Heat of Hollow Nanosphere Coupled to Substrate： Quantum Size Effects

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Communications in Theoretical Physics 2007年第4X期48卷 745-748页

作者： yiN Xue-Ai LUO Bo LIU Fei yi Lin Department of Physics Huazhong University of Science and Technology Wuhan 430074 China

With the help of the elastic wave theory in the perturbed approximation the density-of-states for vibrational modes and the specific heat are studied for different hollow Si nanospheres, coupled with a semi-infinite substrate. We find that the modes of such coupled hollow spheres are significantly broadened and shifted toward low frequencies. The specific heat of the coupled hollow nanosphere is bigger than an isolated one due to the coupling interaction and quantum size effects. The predicted coupling and size enhancements on specific heat are probed in thermal experiments.

关键词： elastic wave size effect specific heat

A huge pancreatic lipoma mimicking a well-differentiated liposarcoma: A case report and systematic literature review

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World Journal of Clinical Cases 2019年第16期7卷 2352-2359页

作者： Ren-yi Xiao Xing Yao Wei-Lin Wang Division of Hepatobiliary and Pancreatic Surgery Department of General SurgeryThe Second Affiliated HospitalSchool of MedicineZhejiang UniversityHangzhou 310009Zhejiang ProvinceChina Department of General Surgery Huzhou Central HospitalHuzhou 313000Zhejiang ProvinceChina

BACKGROUND Pancreatic lipomas are thought to be very *** are usually easy to identify on imaging,particularly via computed tomography (CT).But sometimes it’s quite difficult to distinguish a lipoma from a well-liposarcoma without histologic *** SUMMARY Here,we present a case of pancreatic lipoma in a 59-year-old *** was asymptomatic and had no medical history of *** and magnetic resonance imaging revealed a mass like well-differentiated liposarcoma in the pancreatic head,positron emission tomography/CT showed a low fluorodeoxyglucose uptake and laboratory tests revealed elevated transaminase and carbohydrate antigen-199 ***,the patient underwent a ***,mature adipocytes were noted in the bulk of the ***,the pathologic diagnosis of the pancreatic neoplasm was *** our knowledge,this case is the first example of a suspected well-differentiated liposarcoma that was actually a pancreatic *** also highlight the radiological features distinguishing a pancreatic lipoma from a pancreatic liposarcoma and briefly review the *** Pancreatic lipomas show no obvious gender bias and most commonly occur in the head of the pancreas,of which the maximum diameters are often less than 5 cm,and small,asymptomatic non-compressed lipomas require follow-up *** excision should be considered when the tumor has compressed important tissues or is difficult to distinguish from a liposarcoma,the choice of surgery depends on the intraoperative presentation.

关键词： Pancreatic Lipoma Liposarcoma Pancreas Case report

Gene expression profile analysis reveals the effect of metformin treatment on HepG2 cells

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BIOCELL 2022年第4期46卷 961-967页

作者： yi HUANG CHUNFENG DOU XUMING HU HENGMI CUI School of Pharmacy Suzhou Vocational Health CollegeSuzhou215000China Institute of Epigenetics&Epigenomics Yangzhou UniversityYangzhou225009China

Metformin is a first-line drug in the fight against type 2 *** recent years,studies have shown that metformin has some preventive and therapeutic effects on liver cancer,but the effects of metformin on the gene expression of liver cancer cells are not fully *** study focused on the differences in the gene expression profiles in liver cancer cells treated with or without metformin.A total of 153 differentially expressed genes(DEGs)(FC>2 and q-values<0.001)were found,including 77 upregulated genes and 76 downregulated *** DEGs are involved in mitogen-activated protein kinase(MAPK),nuclear factor-kappa B(NF-κB),cell adhesion molecules(CAMs),and leukocyte transendothelial migration signaling *** findings reveal the effects of metformin treatment on gene expression profiles in liver cancer cells and provide new clues for unveiling the mechanism of the antitumor effects of metformin.

关键词： Metformin Gene expression profiles Antitumor HepG2 cells

Prevalence of Streptococcus suis Isolated from Clinically Healthy Sows in China

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Agricultural Sciences in China 2009年第5期8卷 638-642页

作者： ZHANG Chun-ping NING yi-bao ZHANG Zhong-qiu SONG Li QIU Hui-shen GAO He-yi FAN Xue-zheng Department of lnspection Technology Research China Institute of Veterinary Drug Control Beijing 100081 P.R.China China Animal Disease Control Center Beijing 100026 P.R.China

Streptococcus suis is an important pathogen in pigs. Transmission of this pathogen is generally believed to occur between healthy carrier sows and their offspring, so the carrier status of S. suis in healthy sows is important for the control of S. suis infections in pigs, especially in suckling and growing pigs. In this study, the prevalence of S. suis isolated from clinically healthy sows in China was studied for the first time. A total of 1 043 tonsil samples were collected from clinically healthy sows from 10 regions in China from 2005 to 2007. Among the 421 S. suis isolates, 31 strains were identified as capsular type 2. The results showed that S. suis was widespread in swine herds in China with the carrier rates in different herds ranging from 19.5 to 93.9%. Overall, 40.4 and 3.0% of clinically healthy sows harbored S. suis and capsular type 2 in their palatine tonsils, respectively. Statistically significant differences of carrier rates of S. suis and capsular type 2 between the different farms were observed, which was independent of herd sizes and geographic distributions of different herds.

关键词： Streptococcus suis capsular type 2 prevalence healthy sows

Magnetic resonance imaging and Crohn's disease endoscopic index of severity: Correlations and concordance

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World Journal of Gastroenterology 2018年第21期24卷 2279-2290页

作者： Nai-yi Zhu Xue-Song Zhao Fei Miao Department of Radiology Ruijin HospitalShanghai Jiao Tong University School of Medicine

AIM To examine the correlation between magnetic resonance imaging(MRI) and endoscopic index of severity(CDEIS) in patients with Crohn's disease(CD).METHODS This was a retrospective study of 104 patients with CD that were treated at the Ruijin Hospital between March 2015 and May 2016. Among them, 61 patients with active CD were evaluated before/after treatment. MRI and endoscopy were performed within 7 d. CDEIS was evaluated. MRI parameters included Ma RIA scores, total relative contrast enhancement(tRCE), arterialRCE(aRCE), portalRCE(pRCE), delay phaseRCE(dRCE), and apparent diffusion coefficient. The correlation and concordance between multiple MRI findings and CDEIS changes before and after CD treatment were *** Among the 104 patients, 61 patients were classified as active CD and 43 patients as inactive CD. Gender, age, disease duration, and disease location were not significantly different between the two groups(all P > 0.05). CRP levels were higher in the active group than in the inactive group(25.12 ± 4.12 vs 5.14 ± 0.98 mg/L, P < 0.001). Before treatment, the correlations between CDEIS and MaRIAs in all patients were r = 0.772 for tRCE, r = 0.754 for aRCE, r = 0.738 for pRCE, and r = 0.712 for dRCE(all MaRIAs, P < 0.001), followed by MRI single indexes. Among the active CD patients, 44 cases were remitted to inactive CD after treatment. The correlations between CDEIS and MaRIAs were r = 0.712 for aRCE, r = 0.705 for tRCE, r = 0.685 for pRCE, and r = 0.634 for dRCE(all MaRIAs, P < 0.001).CONCLUSION Arterial Ma RIA should be an indicator for CD follow-up and dynamic assessment. CD treatment assessment was not completely concordant between CDEIS and MRI.

关键词： Magnetic resonance imaging Bowel Crohn’s disease Crohn’s disease endoscopic index of severity Concordance

Chronic progression of recurrent orthokeratinized odontogenic cyst into squamous cell carcinoma:A case report

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World Journal of Clinical Cases 2019年第13期7卷 1686-1695页

作者： Ruo-yi Wu Zhe Shao Tian-Fu Wu The State Key Laboratory Breeding Base of Basic Science of Stomatology (Hubei-MOST) and Key Laboratory of Oral Biomedicine Ministry of Education School and Hospital of Stomatology Wuhan University Wuhan 430072 Hubei Province China Department of Oral and Maxillofacial Surgery School and Hospital of Stomatology Wuhan University Wuhan 430072 Hubei Province China

BACKGROUND Orthokeratinized odontogenic cyst (OOC) is a benign odontogenic cyst. It is a variant of the common odontogenic keratocyst (OKC). This case report describes a rare malignant transformation of OOC, with the aim of raising awareness of the malignant potential of OOC and distinguishing it from OKC. CASE SUMMARY In August 2018, a 52-year-old man was referred to the Department of Oral Maxillofacial and Head–Neck Oncology of Wuhan University. The patient presented with severe pain in the left mandible for 2 mo, and had a 5-year history of osteomyelitis and mandibular cyst with three recurrences. His latest diagnosis by pathological examination was OOC of the left mandible with mild-tomoderate local proliferation. However, the cyst showed malignant potential by radiographic examination. We performed partial mandibulectomy and sent the lesion tissue for pathological examination. As expected, the cyst had deteriorated to moderately differentiated squamous cell carcinoma. During postoperative follow-up, the patient went for chemotherapy in September 2018 and successfully completed four cycles. CONCLUSION Surgeons should be more aware of OOC, which is usually benign but can become malignant.

关键词： Orthokeratinized odontogenic cyst Cancerization Cancer recurrence Squamous cell carcinoma Odontogenic keratocyst Case report

Low-frequency waves in magnetic reconnection

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Chinese Science Bulletin 2012年第12期57卷 1461-1466页

作者： CHAI LiHui LI yi WANG Shui SHEN Chao School of Earth and Space Sciences University of Science and Technology of China Hefei 230026 China National Space Science Center Chinese Academy of Sciences Beijing 100190 China

The characteristics of low-frequency waves in magnetic reconnection are studied using two-dimensional hybrid simulation code. In a coordinate system moving with fluid,the time series of a magnetic field perpendicular to the magnetic reconnection plane,By, is transformed into the power spectrum via fast Fourier transformation,while the wave propagation direction and polarization are determined by minimum variance analysis of the electric *** results show that low-frequency Alfvén ion-cyclotron waves dominate the reconnection *** waves have frequencies 0-1Ωp(where Ωp is the local proton gyro frequency)and all are left-handed circularly *** these waves,large-amplitude turbulence,with frequencies of 0-0.6Ωp and isotropic propagation,dominates the outflow *** can cause the reversal of By in the quadrupole *** the inflow regions, dominant waves,propagating mainly parallel to the ambient magnetic field,have higher frequencies and smaller *** frequency of the main peak of wave energy is usually higher than 0.5Ωp.

关键词：磁场重联低频波快速傅立叶变换传播方向离子回旋波混合模拟坐标系统时间序列

DIURNAL VARIATIONS OF SUMMER PRECIPITATION IN SHANGHAI

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Journal of Tropical Meteorology 2019年第3期25卷 414-420页

作者： HOU yi-ling CHEN Bao-de Nanjing University of Information Science&Technology Nanjing 210044 China Shenyang Regional Climate Center Shenyang 110166 China Shanghai Typhoon Institute China Meteorological AdministrationShanghai 200030 China

This paper investigates the diurnal variations of summer precipitation in Shanghai by using the city’s hourly precipitation data over a span of 35 years. The result shows that the precipitation peaks twice, i.e., in the morning and in the afternoon. Precipitation in the morning is characterized by light to moderate rain, and that in the afternoon by heavy to super heavy rain. The peak of short-duration precipitation is mostly found in the afternoon and at dusk, and that of long-duration precipitation in the morning. Most of the precipitation events in Shanghai are of a short duration of2-3 hours. Basically, the precipitation is spatially distributed in three areas: the eastern coastal and central urban area,where the precipitation peaks mostly in the afternoon, the southern coastal area, where the precipitation peaks both in the afternoon and during the night, and the western area, where long-duration precipitation accounts for a much larger proportion than the other two areas.

关键词： diurnal variation summer precipitation climate pattern Shanghai