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Luo SQ, Cao SJ, Zhao Q. CRISPR/Cas9-Mediated Knockout of the HuR Gene in U251 Cell Inhibits Japanese Encephalitis Virus Replication. Microorganisms 2024; 12:314. [PMID: 38399718 PMCID: PMC10892152 DOI: 10.3390/microorganisms12020314] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/29/2023] [Revised: 01/25/2024] [Accepted: 01/29/2024] [Indexed: 02/25/2024] Open
Abstract
Human antigen R (HuR) is an RNA-binding protein that regulates the post-transcriptional reaction of its target mRNAs. HuR is a critical factor in cancer development and has been identified as a potential target in many cancer models. It participates in the viral life cycle by binding to viral RNAs. In prior work, we used CRISPR/Cas9 screening to identify HuR as a prospective host factor facilitating Japanese encephalitis virus (JEV) infection. The HuR gene was successfully knocked out in U251 cell lines using the CRISPR/Cas9 gene-editing system, with no significant difference in cell growth between U251-WT and U251-HuR-KO2 cells. Here, we experimentally demonstrate for the first time that the knockout of the HuR gene inhibits the replication ability of JEV in U251 cell lines. These results play an essential role in regulating the replication level of JEV and providing new insights into virus-host interactions and potential antiviral strategies. It also offers a platform for investigating the function of HuR in the life cycle of flaviviruses.
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Affiliation(s)
- Sai-Qi Luo
- Research Center for Swine Diseases, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu 611130, China;
- Sichuan Science-Observation Experimental Station of Veterinary Drugs and Veterinary Diagnostic Technique, Ministry of Agriculture and Rural Affairs, Chengdu 611130, China
| | - San-Jie Cao
- Research Center for Swine Diseases, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu 611130, China;
- Sichuan Science-Observation Experimental Station of Veterinary Drugs and Veterinary Diagnostic Technique, Ministry of Agriculture and Rural Affairs, Chengdu 611130, China
- National Demonstration Center for Experimental Animal Education, Sichuan Agricultural University, Chengdu 611130, China
| | - Qin Zhao
- Research Center for Swine Diseases, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu 611130, China;
- Sichuan Science-Observation Experimental Station of Veterinary Drugs and Veterinary Diagnostic Technique, Ministry of Agriculture and Rural Affairs, Chengdu 611130, China
- National Demonstration Center for Experimental Animal Education, Sichuan Agricultural University, Chengdu 611130, China
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Li YH, Luo SQ, Lan L, Jin MG, Yang C, He JY, Li HB, Li CC, Cheng YB, Jin YL. [Influence of extreme weather on years of life lost due to diabetes death in Chongqing and Harbin, China]. Zhonghua Liu Xing Bing Xue Za Zhi 2017; 38:303-308. [PMID: 28329929 DOI: 10.3760/cma.j.issn.0254-6450.2017.03.006] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
Objective: To understand the associations between extremely low and high air temperature and the years of life lost (YLL) due to diabetes deaths in Chongqing and Harbin with different climatic characteristics in China. Methods: A double threshold B-spline distributed lag non-linear model (DLNM) was used to investigate the lag and cumulative effects of extremely low and high air temperature on YLL due to diabetes for lag 0-30 days by using the urban meteorological and diabetes mortality data of Chongqing (2011-2013) and Harbin (2008-2010). The effects were expressed as relative risk (RR). Results: In Chongqing, the cold effects on YLL due to diabetes were delayed by four days and lasted for three days (lag4-6) with the highest RR of 1.304 (95%CI:1.033-1.647) at lag5. The hot effects were delayed by one day (lag1) with RR of 1.321 (95%CI:1.061-1.646). In Harbin, the extreme cold effects on YLL were delayed by four days and lasted for seven days (lag4-10) with the highest RR of 1.309 (95%CI: 1.088-1.575) at lag6. The hot effects were delayed by one day and lasted for four days (lag1-4) with the highest RR of 1.460 (95%CI:1.114-1.915) at lag2. The unit risk for cold and hot effects was 43.7% (P=0.005 5) and 18.0% (P=0.000 2) in Chongqing and 15.0% (P=0.000 8) and 29.5% (P=0.001 2) in Harbin, respectively. Conclusions: Both extremely low air temperature and extremely high air temperature might increase the years of life lost due to diabetes in cities with different climate characteristics. Health education about diabetes prevention should provide information about the effects of extreme weather events.
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Affiliation(s)
- Y H Li
- Division of Policy, Regulation and Standard, National Institute of Environmental Health, Chinese Center for Disease Control and Prevention, Beijing 100021, China
| | - S Q Luo
- Public Health and Safety Monitoring Department, Chongqing Municipal Center for Disease Control and Prevention, Chongqing 404000, China
| | - L Lan
- Division of Chronic Disease Control and Prevention, Harbin Municipal Center for Disease Control and Prevention, Harbin 150056, China
| | - M G Jin
- Qijiang District Center for Disease Control and Prevention of Chongqing, Chongqing 401420, China
| | - C Yang
- Harbin Municipal Center for Disease Control and Prevention, Harbin 150056, China
| | - J Y He
- Public Health and Safety Monitoring Department, Chongqing Municipal Center for Disease Control and Prevention, Chongqing 404000, China
| | - H B Li
- Public Health and Monitoring Center, Harbin Municipal Center for Disease Control and Prevention, Harbin 150056, China
| | - C C Li
- Environmental Epidemiology Department, National Institute of Environmental Health, Chinese Center for Disease Control and Prevention, Beijing 100021, China
| | - Y B Cheng
- Division of Policy, Regulation and Standard, National Institute of Environmental Health, Chinese Center for Disease Control and Prevention, Beijing 100021, China
| | - Y L Jin
- Division of Policy, Regulation and Standard, National Institute of Environmental Health, Chinese Center for Disease Control and Prevention, Beijing 100021, China
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Bai XC, Luo SQ, Bai J, Deng F, Zheng WS, Ji QS. Up-regulation of Phosphatidylinositol-3 Kinase Signaling in plcg1 Gene Null Fibroblasts. Sheng Wu Hua Xue Yu Sheng Wu Wu Li Xue Bao (Shanghai) 2002; 33:677-681. [PMID: 12035061] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Subscribe] [Scholar Register] [Indexed: 02/25/2023]
Abstract
Phospholipase C-gamma1(PLC-gamma1) and phosphatidylinositol-3 kinase(PI-3K) play crucial role in growth factor-induced cell growth and proliferation. To investigate the complementary mechanism of PLC-gamma1 in cell growth and epidermal growth factor (EGF)-induced mitogenic signaling, PLC-gamma1 deficient mouse embryonic fibroblasts(PLC-gamma1(-/-)) and its wild type(PLC-gamma1(+/+)) were exposed to U73122, a phospholipase C-specific inhibitor, or wortmannin, a PI-3K inhibitor then the clonogenicity, viability, EGF-induced DNA synthesis of the two cell lines were determined by cloning formation, MTT method and (3)H -thymidine incorporation assay. Results showed that either U73122 or wortmannin inhibited PLC-gamma1(-/-) and PLC-gamma1(+/+) cells in terms of EGF-induced DNA synthesis, cloning formation and cell viability, but PLC-gamma1(-/-) cells were more dependent on PI-3K and less dependent on PLC compared with wild types. The PLC-gamma1 signaling pathway of PLC-gamma1(-/-) cells might be complemented by PI-3K pathway, because after EGF stimulation, the tyrosine phospholation of p85alpha PI-3K increased significantly in PLC-gamma1(-/-), but not in PLC-gamma2(-/-), as Western blotting showed that there was neither complementary PLC-gamma2 expression in PLC-gamma1(-/-) cells, nor other PLC isozymes such as PLC-beta and PLC-delta. These results suggest the redundancy of EGF-mediated signaling and the complementary mechanism of PLC-gamma1 pathway.
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Affiliation(s)
- X C Bai
- Department of Cell Biology and Medical Genetics, the First Military Medical University, Guangzhou 510515, China.
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Lou M, Song N, Jin X, Luo SQ, Wang JJ. [Detection of serum free insulin-like growth factor 1 in patients with chronic viral hepatitis]. Zhonghua Shi Yan He Lin Chuang Bing Du Xue Za Zhi 2001; 15:291-2. [PMID: 11986710] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/24/2023]
Abstract
OBJECTIVE To evaluate the serum free insulin-like growth factor 1 (IGF-1) level and its relation with the severity and prognosis in patients with chronic viral hepatitis, liver cirrhosis and severe chronic hepatitis. METHODS Serum free IGF-1 was detected by ELISA in 43 patients with chronic viral hepatitis, 20 with liver cirrhosis and 12 with chronic severe hepatitis. RESULTS Serum free IGF-1 was significantly decreased in patients with liver cirrhosis and severe chronic hepatitis. Five patients with chronic severe hepatitis whose serum free IGF-1 was lower than 0.2 ng/l died during follow-up. Four patients whose serum free IGF-1 above 0.3 ng/l survived. Serum free IGF-1 was significantly reduced in patients with albumin lower than 30 g/l. CONCLUSIONS Serum free IGF-1 is decreased in patients with liver cirrhosis and severe chronic hepatitis and it can predict the prognosis of patients with severe chronic hepatitis.
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Affiliation(s)
- M Lou
- The 302nd Hospital of PLA, Beijing 100039, China
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5
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Deng XH, Shi J, Luo SQ, He C, Wang CH, Lu CL. [Trophic effect of ciliary neurotrophic factor on denervated skeletal muscle]. Zhongguo Ying Yong Sheng Li Xue Za Zhi 2001; 17:148-152. [PMID: 21171403] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
AIM The trophic effect of CNTF on skeletal muscle atrophy and dysfunction reduced by denervation was investigated in SD rats. METHODS SD rats transected sciatic nerve in right side hind limbs were injected CNTF subcutaneously for 20 days. Skeletal muscle wet weights, protein contents, muscle fiber cross-sectional areas, contract properties and degree of hind limb abnormalities were observed in the rats. RESULTS (1) Administrating of CNTF (0.2 mg/kg) in sciatic nerve transected SD rats attenuated denervation-induced skeletal muscle fiber atrophy evidently, resulted in gastrocnemius in injury side an obvious increase in contract function, prevented the loss of weights and protein in denervated skeletal muscle, and ameliorated abnormalities in sciatic nerve cut limbs remarkably. (2) The myotrophic effect of 0.2 mg/kg CNTF is more effective than 0.05 mg/kg. (3) The sensitivity to CNTF varied in muscles of different type; slow twitch muscle (soleus muscle) reacted to CNTF stronger and quicker than twitch muscle (extensor digitorum longus). CONCLUSION CNTF significantly attenuates denervation-reduced skeletal muscle atrophy and dysfunction in SD rats, act an evident myotrophic effect on denervated skeletal muscle. And this effect may be exerted in a dosage dependent manner and varies with muscle type.
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Affiliation(s)
- X H Deng
- Department of Neurobiology, Second Military Medical University, Shanghai 200433, China
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Luo SQ. [Study on digitized atlas of the human brain]. Zhongguo Yi Liao Qi Xie Za Zhi 2001; 25:91-90. [PMID: 12583149] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
Digitized Human Brain Atlas is an important tool for visualization of medical images and investigation of brain science. This paper describes its fundamentals, development, construction and applications in surgical planning, model-driven segmentation and neuroanatomy teaching.
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Affiliation(s)
- S Q Luo
- Biomedical Engineering Department, Capital University of Medical Sciences
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7
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Ben LH, Zhao J, Xin SM, Luo SQ, Pei G. Attenuation of delta opioid receptor-mediated signaling by kainic acid in neural cells: involvement of protein kinase C and intracellular Ca2+. Neuropharmacology 1999; 38:991-8. [PMID: 10428417 DOI: 10.1016/s0028-3908(99)00036-2] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
The potential modulation of opioid receptor signaling by kainic acid (KA) has been investigated in neuroblastoma x glioma NG 108-15 hybrid cells and neuroblastoma SK-N-SH cells. Acute incubation of KA significantly attenuated delta opioid receptor (DOR) signaling induced by the DOR agonist [D-Pen2, D-Pen5]-enkephalin (DPDPE), as measured by activation of G proteins and inhibition of cAMP accumulation. The attenuation by KA was time- and dose-dependent and could be blocked by antagonists of kainate/AMPA receptors, suggesting possible mediation through kainate/AMPA receptors. KA attenuation of DPDPE-stimulated G protein activation was reversed by inhibitors of protein kinase C or by removal of both extracellular Ca2+ and intracellular Ca2+. In contrast, NMDA attenuation of DPDPE-stimulated G protein activation was independent of intracellular Ca2+, indicating that different mechanism(s) may underlie the modulation effect of KA and NMDA. This notion was further supported by the results that KA did not alter nociceptin/orphanin FQ-stimulated G protein activation in NG 108-15 cells but NMDA did. In addition, pretreatment of NG 108-15 cells with antagonists of kainate/AMPA receptors blocked the acute desensitization of DOR signaling. These data provide evidence that KA may be involved in the modulation of opioid receptor signal transduction.
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MESH Headings
- Animals
- Calcium/metabolism
- Enkephalin, D-Penicillamine (2,5)-
- Enkephalins/pharmacology
- Excitatory Amino Acid Agonists/pharmacology
- GTP-Binding Proteins/metabolism
- Kainic Acid/pharmacology
- Mice
- Neurons/cytology
- Neurons/drug effects
- Neurons/enzymology
- Neurons/metabolism
- Protein Kinase C/metabolism
- Receptors, AMPA/drug effects
- Receptors, AMPA/metabolism
- Receptors, Opioid/drug effects
- Receptors, Opioid/metabolism
- Receptors, Opioid, delta/agonists
- Receptors, Opioid, delta/antagonists & inhibitors
- Receptors, Opioid, delta/metabolism
- Signal Transduction/drug effects
- Tumor Cells, Cultured
- Nociceptin Receptor
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Affiliation(s)
- L H Ben
- Shanghai Institute of Cell Biology and Shanghai Research Center of Life Sciences, Chinese Academy of Sciences, Peoples Republic of China
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8
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Bai JZ, Bian JG, Chen GP, Chen HF, Chen SJ, Chen SM, Chen Y, Chen YQ, Chen YB, Cheng BS, Cui XZ, Ding HL, Ding WY, Du ZZ, Fan XL, Fang J, Gao CS, Gao ML, Gao SQ, Gu JH, Gu SD, Gu WX, Gu YF, Guo YN, Han SW, Han Y, He J, He M, Hu GY, Hu T, Hu XQ, Huang DQ, Huang T, Huang YZ, Jiang CH, Jin S, Jin Y, Kang SH, Ke ZJ, Lai YF, Lan HB, Lang PF, Li F, Li J, Li PQ, Li Q, Li RB, Li W, Li WD, Li WG, Li XH, Li XN, Lin SZ, Liu HM, Liu J, Liu JH, Liu Q, Liu RG, Liu Y, Liu ZA, Lu JG, Luo SQ, Luo Y, Ma AM. Studies of xi (2230) in J/ psi radiative decays. Phys Rev Lett 1996; 76:3502-3505. [PMID: 10060984 DOI: 10.1103/physrevlett.76.3502] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
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Abstract
Two new polyoxypregnanes, designated marstenacigenins A and B, along with a known compound, dresgenin, were isolated from the mild acid hydrolysate of the ethanol extract of the stems of Marsdenia tenacissima. Their structures were deduced by a combination of 1D and 2D NMR spectroscopic techniques as 12 beta-cinnamoyl-dihydrosarcostin and 12 beta,20-dibenzoyldihydrosarcostin, respectively.
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Affiliation(s)
- S X Qiu
- Department of Medicinal Chemistry and Pharmacognosy, University of Illinois at Chicago 60612, USA
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Luo SQ, Liu XZ, Wang CJ. Inhibitory effect of green tea extract on the carcinogenesis induced by asbestos plus benzo(a)pyrene in rat. Biomed Environ Sci 1995; 8:54-58. [PMID: 7605600] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/21/2023]
Abstract
In this experiment lung carcinoma was induced by crocidolite plus benzo(a)pyrene in rat. From the cancer models, we observed that the incidence (16.0%) of lung carcinomas was lower, and the survival time (376 days) of the first case of carcinoma and the mean survival time (758 days) of the rats with carcinoma were higher in the group of rats drinking 2% green tea extract for life than in the positive group (without drinking green tea extract). The mortality ratio (0.5047) was smaller in the experimental group than in the positive control group, and the survival curve of the experimental group significantly raised up, in comparison with the positive group.
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Affiliation(s)
- S Q Luo
- Department of Occupational Health, School of Public Health, West China University of Medical Sciences, Chengdu
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11
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Abstract
From the roots of Bupleurum wenchuanense 14 derivatives of saikosaponin were isolated and identified as 2"-O-beta-D-xylopyranosylsaikosaponin b2, 3",6"-O O-diacetylsaikosaponin b2, 2"-O-beta-D-glucopyranosylsaikosaponin b2, saikosaponin b2, 6"-O-acetylsaikosaponin b2, saikosaponin d, 2"-O-acetylsaikosaponin d, 3"-O-acetylsaikosaponin d,6"-O-acetylsaikosaponin d, 16-epichikusaikoside, prosaikogenin G, saikosaponin a,2"-O-acetylsaikosaponin a and 3"-O-acetylsaikosaponin a. The first two compounds are new derivatives of saikosaponin and this is the first isolation of prosaikogenin G from a plant. Their complete 1H and 13C NMR assignments were made by using a combination of 2D NMR techniques (DQF-COSY, HOHAHA, ROESY, HETCOR, HMQC and HMBC). Some of the compounds showed cytotoxic activity against the P-388 cell line.
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Affiliation(s)
- S Q Luo
- Department of Medicinal Chemistry and Pharmacognosy, College of Pharmacy, University of Illinois at Chicago
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Luo SQ, Plowman MC, Hopfer SM, Sunderman FW. Mg(2+)-deprivation enhances and Mg(2+)-supplementation diminishes the embryotoxic and teratogenic effects of Ni2+, Co2+, Zn2+, and Cd2+ for frog embryos in the FETAX assay. Ann Clin Lab Sci 1993; 23:121-9. [PMID: 8457141] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Abstract
The influence of Mg2+ on the embryotoxicity and teratogenicity of Ni2+, Co2+, Zn2+, and Cd2+ for Xenopus embryos was studied by an adaptation of the FETAX protocol. In seven assays, 25 groups of embryos were grown from 5 to 101 hours post-fertilization in FETAX media that contained five graded MgCl2 concentrations (0, 6.2, 62, 620, or 6,200 mumol per L), with or without added NiCl2 (56 mumol per L), CoCl2 (1,800 mumol per L), ZnCl2 (300 mumol per L), or CdCl2 (18 mumol per L). In FETAX assays performed with the standard Mg2+ concentration (620 mumol per L), the incidence of malformations in control embryos averaged 5.4 (SD +/- 1.3) percent; the incidence of malformations in the controls was increased at low Mg2+ concentrations (32 +/- 7 percent at 62 mumol per L; 100 percent at greater than or equal to 6.2 mumol per L). The specified additions of Ni2+, Co2+, Zn2+, or Cd2+ caused death in < 10 under standard conditions (620 mumol Mg2+ per L). Mg(2+)-deprivation greatly enhanced and Mg(2+)-supplementation significantly reduced the incidence and severity of the teratogenic and embryotoxic effects of Ni2+, Co2+, Zn2+, and Cd2+ (p < 0.0001 by analysis of variance [ANOVA]). To explain these findings, the authors speculate that Mg2+ competes with the other divalent metal ions for a carrier mechanism involved in metal absorption or cellular uptake, or for binding to critical molecular targets.
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Affiliation(s)
- S Q Luo
- Department of Laboratory Medicine, University of Connecticut School of Medicine, Farmington 06030
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13
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Luo SQ, Plowman MC, Hopfer SM, Sunderman FW. Embryotoxicity and teratogenicity of Cu2+ and Zn2+ for Xenopus laevis, assayed by the FETAX procedure. Ann Clin Lab Sci 1993; 23:111-20. [PMID: 8457140] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Abstract
Cupric chloride (CuCl2) and zinc chloride (ZnCl2) were tested by the FETAX (Frog Embryo Teratogenesis Assay: Xenopus) procedure in the South African frog, Xenopus laevis. The median teratogenic concentrations (EC50) of Cu2+ and Zn2+ were 2.5 and 40 mumol per L. The median embryolethal concentrations (LC50) of Cu2+ and Zn2+ were 22 and 850 mumol per L. The teratogenic indices (TI = LC50/EC50) were 8.8 for Cu2+ and 21 for Zn2+. Both metal ions were shown to be potent teratogens for Xenopus, causing concentration-related increases of eye, gut, facial, notochord, and cardiac anomalies.
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Affiliation(s)
- S Q Luo
- Department of Laboratory Medicine, University of Connecticut School of Medicine, Farmington 06030
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14
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Abstract
Homologous recombination between two duplex DNA molecules might result in two duplex DNA molecules (conservative) or, alternatively, it might result in only one recombinant duplex DNA molecule (nonconservative). Here we present evidence that the mode of homologous recombination is nonconservative in an Escherichia coli strain with an active RecF pathway (a recBC sbcBC mutant). We employed plasmid substrates that enable us to recover both recombination products. These plasmids carry two mutant alleles of neo gene in direct orientation, two drug-resistance marker genes, and two compatible replication origins. After their transfer to the cells followed by immediate selection for the recombination to neo+, we could recover only one recombination product. A double-strand break at the region of homology increased this nonconservative recombination. If a nonconservative exchange should leave an end, this end may stimulate another exchange. Such "successive half crossing-over events" can explain several recombination-related phenomena in E. coli, including the origin of plasmid linear multimers and of transcribable, nonreplicated recombination products, and also in yeast and mammalian cells.
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Affiliation(s)
- N K Takahashi
- Department of Bacteriology, Faculty of Medicine, University of Tokyo, Japan
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15
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Luo SQ, Li DZ, Dong JF. Intracranial tumors in children. An analysis of 2000 cases. Chin Med J (Engl) 1992; 105:462-8. [PMID: 1333390] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022] Open
Abstract
Two thousand patients aged 15 years and below, who underwent surgical treatment for intracranial tumors in Beijing Tiantan Hospital from 1955 to 1989, were studied. All of the tumors in this series have been verified by operative findings and histological studies. This series accounts for 15.1% of all cases of intracranial tumors treated within the same period. The characteristics of the histological classifications, locations and clinical manifestations of the intracranial tumors in children are presented. Stresses are placed on the importance of making correct diagnoses in the early stage. Misdiagnoses had been made in 1/4 of the cases in this series before they came to our hospital, thus causing much delayed treatment in many of them. Malignant tumors make up a majority of intracranial tumors in children, and so the prognoses of intracranial tumors are poorer in children than in adults. The authors are of the opinion that adequate radiotherapy is needed after surgical intervention for many of the intracranial tumors.
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Affiliation(s)
- S Q Luo
- Beijing Neurosurgical Institute
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16
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Abstract
Food intake, diet selection and body weight gain were examined in three separate experiments in which rats received saline or one of three serotonergic agonists, dexfenfluramine, RU 24969 and fluoxetine. In all experiments, food was available only in the dark period during which time rats were given simultaneous access to two isoenergetic diets which differed in their protein and carbohydrate content. After habituation to this feeding paradigm and intraperitoneal injections, rats were assigned to control or drug group. Saline or a serotonergic agonist was given to the same rat once daily, 15 min prior to feeding, for six consecutive days. All three agonists (1.5 mg/kg for dexfenfluramine and RU 24969; 3 mg/kg for fluoxetine) caused immediate (first two h of feeding) hypophagia which was accounted for by the selective suppression in intake of the high-carbohydrate-low-protein diet. This selective shift in diet choice was sustained upon repeated exposure. Although the effects of these agonists on daily (12-h) feeding was less pronounced, appetite suppression was due entirely to reduced intake of the high-carbohydrate-low-protein diet. Of the three agonists tested, partial tolerance was observed only after dexfenfluramine. Nevertheless, all three agonists caused comparable declines in weight gain. These results suggest that repeated administration of serotonergic agonists has sustained impacts on food intake, diet choice and weight gain.
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Affiliation(s)
- S Q Luo
- Department of Nutritional Sciences, University of Toronto, Ontario, Canada
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17
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Abstract
The effects of two indirect (dexfenfluramine and fluoxetine) and one direct (RU 24969) serotonergic agonists on diet selection over a 12-hr period were examined. Rats were habituated to eat, during the dark period, from two isoenergetic diets that differed in carbohydrate and protein content. Drugs were injected intraperitoneally at 1845 hr, 15 min prior to food access. The drugs exerted their effects mainly during the first hour of feeding (1900-2000 hr). At this time, a selective suppression in intake of the high carbohydrate-low protein diet was the most prominent characteristic of all three serotonergic agonists. This macronutrient specific effect was particularly strong at low dosages (dexfenfluramine, fluoxetine and RU 24969: 0.5, 2.0 and 1.0 mg/kg, respectively). With time, as the effect of drugs wore off, diet selection pattern became more variable. The fact that both indirect 5-HT agonists and a direct selective 5-HT receptor agonist share a specific behavioral effect provides additional support for the role of serotonin in the control of macronutrient specific appetites.
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Affiliation(s)
- S Q Luo
- Department of Nutritional Sciences, University of Toronto, Ontario, Canada
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18
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Abstract
Both 8-hydroxy-2-(di-n-propylamino)-tetraline (8-OH-DPAT) and buspirone (BUSP) were found to induce food intake in free-feeding, self-selecting young rats. The hyperphagia was macronutrient specific. In rats given simultaneous access to two diets which differed in carbohydrate and protein content, 8-OH-DPAT and BUSP selectively increased intake from the diet with high carbohydrate content during a two hour test. This specific behavioral effect is dose-dependent and is opposite to that induced by serotonin releasers or reuptake inhibitors. In a separate experiment, the selective decrease in carbohydrate intake after fluoxetine (FLX) was blocked by 8-OH-DPAT co-administration. These results further support a role for the serotonergic system in the control of feeding and macronutrient specific appetites.
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Affiliation(s)
- S Q Luo
- Department of Nutritional Sciences, University of Toronto, Ontario, Canada
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19
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Dong YY, Luo SQ. [Determination of saikosaponins in radix Bupleuri using HPLC]. Zhongguo Zhong Yao Za Zhi 1989; 14:678-81, 703-4. [PMID: 2619895] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
A high performance liquid chromatographic method for the determination of saikosaponin a, c and d in Radix Bupleuri was developed. YMC-pack A-314 ODS column (6 x 300mm) with an eluent consisting of acetone-water (58:42) at a flow rate of 1.2 ml/min was used. The saikosaponins were monitored by a differential refractometer without being converted into the corresponding diene derivatives in advance. Megestrol was used as the internal standard. The recovery rate of saikosaponins was higher than 95% and the coefficient of variation (CV) was 3.08%. The contents of saikosaponins a, c and d of 13 species of Radix Bupleuri collected in different districts of China were evaluated by this method.
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Sakai M, Luo SQ, Tanaka T, Ogawa K. Distribution of electric charges and concanavalin A binding sites on autophagic vacuoles and lysosomes in mouse hepatocytes. Exp Cell Res 1989; 185:143-53. [PMID: 2806405 DOI: 10.1016/0014-4827(89)90044-x] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
The distributions of electric charges and Concanavalin A binding sites in autophagic vacuoles and lysosomes in mouse hepatocytes were studied by utilizing a frozen ultrathin section labeling method with cationized ferritin (CF) or anionized ferritin and ferritin-conjugated Concanavalin A (Con A-F) as visual probes. Our observations revealed that the inner surface of the autophagic vacuole membrane has more anionic sites (CF binding) than other organelle membranes. This suggests that if the limiting membranes of autophagic vacuoles originate from preexisting membranes, such membranes must undergo structural and compositional alternation during the formation of the autophagic vacuoles. In contrast to CF, Con A-F showed no distinct binding to the membranes of autophagic vacuoles, but the contents of vacuoles displayed varying Con A-F binding, depending on the stage of the autophagic process. Increased binding was seen in more mature autophagic vacuoles. Since lysosomes showed a preferential accumulation of Con A-F particles, molecules with Con A-F binding sites in autophagic vacuoles may be of lysosomal origin. Con A-F distribution varied from lysosome to lysosome in the same cell, indicating heterogeneity of lysosomal contents. These results suggest that ferritin-conjugated lectin labeling methods applied to frozen, ultrathin section are a useful new approach in analyzing the natural history of autophagic vacuoles and the heterogeneity of lysosomes.
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Affiliation(s)
- M Sakai
- Department of Anatomy, Faculty of Medicine, Kyoto University, Japan
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Luo SQ, Li DZ, Zhang MZ, Wang ZC, Zhong CW. Occipital transtentorial approach for removal of pineal region tumors: report of 64 consecutive cases. Surg Neurol 1989; 32:36-9. [PMID: 2734686 DOI: 10.1016/0090-3019(89)90032-3] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
A series of 64 patients with pineal region tumors operated on between 1981 and 1985 at the Beijing Neurosurgical Institute is reported. All were approached using an occipital transtentorial technique. A gross total or radical subtotal removal was achieved in 87% with a total mortality and morbidity of less than 10%. The relative advantages of this particular approach to the pineal region are discussed. It is concluded that the transtentorial approach to the pineal region provides excellent visualization and circumvents many of the pitfalls of other approaches to this region.
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Affiliation(s)
- S Q Luo
- Beijing Neurosurgical Institute, Tiantan Xili, People's Republic of China
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22
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Yang GH, Tan YS, Liu XZ, Luo SQ. [Ultrastructural and immunohistochemical study of mesothelioma induced by asbestos in rat]. Hua Xi Yi Ke Da Xue Xue Bao 1988; 19:337-41. [PMID: 3243527] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
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23
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Abstract
Grafts of neonatal striatal tissue were placed into the striata of adult rats. When challenged immediately with intrastriatal injections of either kainic or quinolinic acid, excitotoxic damage was prevented. Thirty days later these same graft recipients received another injection of excitotoxin. The intrastriatal grafts continued to mitigate toxin-induced damage. It is hypothesized that the grafted cells not only survive, but that they may continue to elaborate some substance or substances that prevent excitotoxin-induced injury for at least 30 days. Previous investigations indicated that grafts of neonatal striatal tissue can protect the recipient striatum from kainic acid toxicity. In the following study it is demonstrated that such grafts also protect the striatum from quinolinic acid, an endogenous excitotoxin which induces kainate-like neuronal degeneration and has been implicated in the pathogenesis of Huntington's disease. It is postulated that the salutary effect of striatal grafting may be sufficiently long lasting to mitigate a chronic toxic insult. Such grafting may therefore represent a therapy for Huntington's disease and other neurodegenerative disorders in which an endogenous or exogenous toxin has been implicated as the pathogenetic agent.
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Affiliation(s)
- N Tulipan
- Department of Neurological Surgery, Vanderbilt University Medical Center, Nashville, Tennessee 37232
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24
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25
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Luo SQ, Jin HF. [Chemical constituents of the aerial parts of Bupleurum chinese DC]. Zhong Yao Tong Bao 1988; 13:36-8, 63. [PMID: 3396126] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
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26
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Luo SQ, Liao CX, McClelland JF, Graves DJ. Formation of a cyclic imide in aspartyl or asparaginyl glycyl peptides induced by heating in the dry state. Int J Pept Protein Res 1987; 29:728-33. [PMID: 3623803 DOI: 10.1111/j.1399-3011.1987.tb02305.x] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
A common product was identified by HPLC from the heating of, alpha and beta isomers of, aspartyl glycine in the dry state. Fast atom-bombardment (FAB) mass spectrometry and Fourier transform infrared photoacoustic spectroscopy (FTIR-PAS) showed that the product is a cyclic imide. Cyclic imide formation also was shown to occur with the tripeptides Gly-Asp-Gly and Gly-Asn-Gly. The cyclization of aspartyl peptides depends upon protonation of the beta-carboxyl group and can be promoted by acidification or by heating the NH4+ salt in the dry state.
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27
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Luo SQ, Zhang YX. [Ultrastructure of brain tumor]. Zhonghua Zhong Liu Za Zhi 1987; 9:115-7. [PMID: 2820679] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
Ultrastructure of 15 brain tumors (6 astrocytomas, 5 meningiomas, 2 medulloblastomas and 2 Schwannomas) was observed by transmission electron microscope. In astrocytoma, both the fibrous and protoplasmic astrocytes were found. There were abundant capillaries among the tumor cells. The glia limitans outside the base membrane of certain capillaries were destroyed to different degrees. It indicates that the blood brain barrier may be damaged. Ultrastructurally, medulloblastoma cells may be divided into types I and II. The former was poorly differentiated but the latter was differentiated differently. Meningioma was similar to Schwannoma with complex cell membrane projections. The former had a lot of round mitochondria and filaments in the projections, between which desmosomes were observed. Schwannoma had the typical collagenous fibers among the projections. As to the epithelioid ultrastructure of meningioma, the authors speculate that the majority of meningiomas originate from the mesothelial cells of the arachnoid granulations.
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Affiliation(s)
- S Q Luo
- First Military Medical University, PLA, Guangzhou
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28
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Wang XS, Xue YS, Jiang Y, Ni HL, Zhu H, Luo BG, Luo SQ. Occupational contact dermatitis in manufacture of vanillin. Chin Med J (Engl) 1987; 100:250-4. [PMID: 2957179] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023] Open
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29
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Zhou CC, Sun XB, Liu JY, Luo SQ, Lu CY. [Anti-inflammatory effect of alpha-spinasterol]. Yao Xue Xue Bao 1985; 20:257-61. [PMID: 4072696] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
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30
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Liu XZ, Luo SQ. [Determination of airborne asbestos fiber concentration and fiber size distribution by phase contrast microscopy]. Zhonghua Yu Fang Yi Xue Za Zhi 1983; 17:82-5. [PMID: 6347566] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
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31
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Luo SQ. [Intracranial choroid plexus papilloma in children]. Zhonghua Zhong Liu Za Zhi 1982; 4:298-300. [PMID: 6984677] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
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32
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Luo SQ. [Infratentorial supracerebellar approach for removing tumors of the pineal region in children (author's transl)]. Zhonghua Wai Ke Za Zhi 1982; 20:184-5. [PMID: 7094765] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
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33
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Luo SQ. [Primary tumors of the skull in children (author's transl)]. Zhonghua Zhong Liu Za Zhi 1981; 3:274-6. [PMID: 7341179] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
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34
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Luo SQ. [Tumors of the lateral ventricles in children (author's transl)]. Zhonghua Zhong Liu Za Zhi 1981; 3:129-31. [PMID: 7307894] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
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35
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Yin GK, Ma BZ, Guo YX, Yang Y, Sun Y, Qu BZ, Ho YN, Luo SQ, Zhu SQ. [Studies on the stability of 25% ascorbic acid injection. II. Prediction of the shelflife of 25% ascorbic acid injection (author's transl)]. Yao Xue Xue Bao 1980; 15:298-302. [PMID: 7457148] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
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36
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Luo SQ. [Intracranial arteriovenous malformations in children (author's transl)]. Zhonghua Wai Ke Za Zhi 1980; 18:241-3. [PMID: 7472076] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
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