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1.
Resolving the conflicts between biodiversity conservation and socioeconomic development is a global pursuit for the long-run prospects of the human species. Based on Wenchuan County, a typical county in southwestern China, a group of 20 indicators quantifying regional biodiversity and socioeconomic development was established to classify and evaluate the county area spatially. A fuzzy c-means clustering (FCM) algorithm was used as the classification method. Three indices including BD, DL and DR characterizing the value of biodiversity, the level and rate of socioeconomic development of the delineated regions were formulated. The results indicated that Wenchuan County was optimally classified into 4 types of regions (region I to IV). The area percentages of the regions vary widely from 4.3 to 65.7%. The sequences of the regions on biodiversity, socioeconomic development level, and socioeconomic development rate were, respectively, IV > II > III > I, I > III > II > IV and III >I >II >IV. The spatial strategy on coordinating biodiversity conservation and regional development is to develop mainly from the east(I, II, III) and to conserve mainly in the west(IV). Eco-industry, such as eco-tourism and eco-agriculture, need to be emphasized in the process of regional development. The quantitative methods used here may have a wide applicability.  相似文献   
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Inheritance of gusA and neo genes in transgenic rice   总被引:21,自引:0,他引:21  
Inheritance of foreign genes neo and gusA in rice (Oryza sativa L. cv. IR54 and Radon) has been investigated in three different primary (T0) transformants and their progeny plants. T0 plants were obtained by co-transforming protoplasts from two different rice suspension cultures with the neomycin phosphotransferase II gene [neo or aph (3) II] and the -glucuronidase gene (uidA or gusA) residing on separate chimeric plasmid constructs. The suspension cultures were derived from callus of immature embryos of indica variety IR54 and japonica variety Radon. One transgenic line of Radon (AR2) contained neo driven by the CaMV 35S promoter and gusA driven by the rice actin promoter. A second Radon line (R3) contained neo driven by the CaMV 35S promoter and gusA driven by a promoter of the rice tungro bacilliform virus. The third transgenic line, IR54-1, contained neo driven by the CaMV 35S promoter and gusA driven by the CaMV 35S.Inheritance of the transgenes in progeny of the transgenic rice was investigated by Southern blot analysis and enzyme assays. Southern blot analysis of genomic DNA showed that, regardless of copy numbers of the transgenes in the plant genome and the fact that the two transgenes resided on two different plasmids before transformation, the introduced gusA and neo genes were stably transmitted from one generation to another and co-inherited together in transgenic rice progeny plants derived from self-pollination. Analysis of GUS and NPT II activities in T1 to T2 plants provided evidence that inheritance of the gusA and neo genes was in a Mendelian fashion in one plant line (AR2), and in an irregular fashion in the two other plant lines (R3 and IR54-1). Homozygous progeny plants expressing the gusA and neo genes were obtained in the T2 generation of AR2, but the homozygous state was not found in the other two lines of transgenic rice.  相似文献   
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诺卡菌肺部感染可引起肺诺卡菌病,因其无特异性的临床表现,容易误诊、漏诊。因此,临床实验室的培养鉴定能力非常重要,若不能及时诊治,则会导致病死率较高。诺卡菌病临床较为少见,为引起临床实验室对诺卡菌的鉴定和药敏试验的重视,本文报道了上海市嘉定区中心医院2019年2月收治的1例由圣乔治教堂诺卡菌(Nocardia cyriacigeorgica)感染引起的肺诺卡菌病病例,针对其临床特征、实验室检测及治疗等进行分析,期望对临床诊治诺卡菌病有所帮助。  相似文献   
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1,5-Diazido-3-nitrazapentane (DANP) and 1,7-diazido-2,4,6-trinitrazaheptane (DATNH) are two energetic plasticizers. To better understand them, a detailed theoretical investigation was carried out using density functional theory and molecular mechanics methods. The crystal structures, spectra, thermodynamic properties, heats of formation, detonation velocity, detonation pressure, specific impulse and thermal stability were estimated. Possible initiation steps of pyrolysis were discussed by considering the bond breaking of N–NO2, C–N3, and N–N2 (via hydrogen transfer) for both compounds and the cyclization of the adjacent nitro and azido groups for DATNH. Results show that the rupture of N–NO2 and N–N2 (via hydrogen transfer) may happen simultaneously as the initial step of pyrolysis. Both crystals have P-1 symmetry as was observed experimentally. DANP has higher stability than DATNH, while DATNH has better detonation performance than DANP. In addition, DANP has a lower while DATNH has a higher specific impulse than RDX, which shows their prospects as propellant components.  相似文献   
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The plant-pathogenic bacterium Xanthomonas oryzae pv. oryzae (Xoo) is the causal agent of bacterial blight, which is one of the most serious diseases of rice. Xoo has been studied for over one century, and much has been learned about it, but proteomic investigation has been neglected. In this study, proteome reference maps of Xoo were constructed by two-dimensional gel electrophoresis, and 628 spots in the gels representing 469 different protein species were identified with MALDI-TOF/TOF MS. The identified spots were assigned to 15 functional categories according to the Kyoto Encyclopedia of Genes and Genomes (KEGG) database and the annotations from the National Center for Biotechnology Information (NCBI) database. The data set has been deposited in the World-2DPAGE database (Database ID: 0044). In addition, comparative proteomic analysis revealed that proteins related to the TonB-dependent transportation system and energy metabolism are involved in the phenazine-1-carboxylic acid resistance in Xoo. In conclusion, we have established a proteome database for Xoo and have used this database in a comparative proteomic analysis that identified proteins potentially contributing to phenazine-1-carboxylic acid resistance in Xoo.  相似文献   
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Esophageal cancer is common in China. There is a lack of treatment strategies for metastatic esophageal cancer (MEC) after radical surgery on the primary tumor. Cryoablation is an attractive option because tumor necrosis can be safely induced in a minimally invasive manner. This study assessed its therapeutic effect in MEC after failure of radical surgery. One hundred and forty patients met the inclusion criteria from May, 2003 to March, 2011. Comprehensive cryotherapy of multiple metastases was performed on 105 patients; 35 received chemotherapy. No severe complications occurred during or after cryoablation. Overall survival (OS) was assessed according to therapeutic protocol, pathologic type, treatment timing and number of procedures. The OS of patients who received comprehensive cryoablation (44 ± 20 months) was significantly longer than that of those who underwent chemotherapy (23 ± 24 months; P = 0.0006). In the cryotherapy group, the OS for squamous cell carcinoma (45 ± 19 months) was longer than that for adenocarcinoma (33 ± 18 months; P = 0.0435); the OS for timely cryoablation (46 ± 19 months) was longer than that for delayed cryoablation (33 ± 20 months; P = 0.0193); the OS for multiple cryoablation (50 ± 17 months) was longer than that for single cryoablation (37 ± 20 months; P = 0.0172); and the OS for cryo-immunotherapy (56 ± 17 months) was longer than that for cryoablation alone (39 ± 19 months; P = 0.0011). Thus, comprehensive cryotherapy may have advantages over chemotherapy in the treatment of MEC and, in patients with squamous cell carcinoma, supplementary immunotherapy and timely and multiple cryoablation may be associated with a better prognosis.  相似文献   
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A novel functional single nucleotide polymorphism (SNP) rs2274223 located in the phospholipase C epsilon 1 (PLCE1) gene was found to be associated with the risk of esophageal squamous cell carcinoma (ESCC) by three large-scale genome-wide association studies (GWAS) in Chinese populations. In the present study, we validated this finding and also explored the risk of ESCC associated with other two unreported potentially functional SNPs (rs17417407 G > T and rs2274224 C > G) of PLCE1 in a population-based case–control study to investigate the association between these three potentially functional SNPs in PLCE1 and susceptibility to ESCC. A total of 381 ESCC cases and 420 controls matched by age and sex were recruited and successfully genotyped for three SNPs (rs17417407, rs2274223 and rs2274224) of the PLCE1 in a central Chinese population. SNP rs2274223 was independently associated with increased risk of ESCC (adjusted odds ratio [OR], 2.80; 95% confidence interval [95% CI], 1.45–5.39 for GG vs. AA), and SNP rs2274224 was found to be associated with decreased risk of ESCC (adjusted OR, 0.65; 95% CI, 0.46–0.91 for CG vs. CC). The combined effects of risk alleles for three SNPs (rs17417407T, rs2274223G and rs2274224G) were found to be associated with elevated risk of ESCC in a dose-dependent effect manner (Ptrend = 0.005). The Grs17417407Ars2274223Crs2274224 haplotype decreased the risk of ESCC (adjusted OR, 0.76; 95% CI, 0.62–0.93), meanwhile the Grs17417407Grs2274223Crs2274224 and Trs17417407Grs2274223Crs2274224 haplotypes could increase the risk of ESCC (adjusted OR, 1.75; 95% CI, 1.33–2.18 and OR, 2.51; 95% CI, 1.15–2.49). Gene–environment interaction analysis presented a best model consisted of four factors (rs2274223, rs2274224, family history, and smoking) with testing balance accuracy (TBA): 0.66 and cross validation consistency (CVC): 7/10, which could increase the esophageal cancer risk in the “high risk group” with 3.67-fold (OR: 3.67, 95% CI: 2.74–4.92), compared to the “low risk group”. Our results further confirmed that genetic variations in PLCE1 may contribute to ESCC risk associated with tobacco exposure in a central Chinese population. Further functional studies are needed to validate our results.  相似文献   
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