BACKGROUND Extrahepatic cholangiocarcinoma sarcoma is extremely rare in clinical practice.These cells consist of both epithelial and mesenchymal cells.Patient-derived cell lines that maintain tumor characteristics are...BACKGROUND Extrahepatic cholangiocarcinoma sarcoma is extremely rare in clinical practice.These cells consist of both epithelial and mesenchymal cells.Patient-derived cell lines that maintain tumor characteristics are valuable tools for studying the molecular mechanisms associated with carcinosarcoma.However,cholangiocarcinoma sarcoma cell lines are not available in cell banks.AIM To establish and characterize a new extrahepatic cholangiocarcinoma sarcoma cell line,namely CBC2T-2.METHODS We conducted a short tandem repeat(STR)test to confirm the identity of the CBC2T-2 cell line.Furthermore,we assessed the migratory and invasive properties of the cells and performed clonogenicity assay to evaluate the ability of individual cells to form colonies.The tumorigenic potential of CBC2T-2 cells was tested in vivo using nonobese diabetic/severe combined immunodeficient(NOD/SCID)mice.The cells were injected subcutaneously and tumor formation was observed.In addition,immunohistochemical analysis was carried out to examine the expression of epithelial marker CK19 and mesenchymal marker vimentin in both CBC2T-2 cells and xenografts.The CBC2T-2 cell line was used to screen the potential therapeutic effects of various clinical agents in patients with cholangiocarcinoma sarcoma.Lastly,whole-exome sequencing was performed to identify genetic alterations and screen for somatic mutations in the CBC2T-2 cell line.RESULTS The STR test showed that there was no cross-contamination and the results were identical to those of the original tissue.The cells showed round or oval-shaped epithelioid cells and mesenchymal cells with spindle-shaped or elongated morphology.The cells exhibited a high proliferation ratio with a doubling time of 47.11 h.This cell line has migratory,invasive,and clonogenic abilities.The chromosomes in the CBC2T-2 cells were polyploidy,with numbers ranging from 69 to 79.The subcutaneous tumorigenic assay confirmed the in vivo tumorigenic ability of CBC2T-2 cells in NOD/SCID mice.CBC2T-2 cells and xenografts were positive for both the epithelial marker,CK19,and the mesenchymal marker,vimentin.These results suggest that CBC2T-2 cells may have both epithelial and mesenchymal characteristics.The cells were also used to screen clinical agents in patients with cholangiocarcinoma sarcoma,and a combination of paclitaxel and gemcitabine was found to be the most effective treatment option.CONCLUSION We established the first human cholangiocarcinoma sarcoma cell line,CBC2T-2,with stable biogenetic traits.This cell line,as a research model,has a high clinical value and would facilitate the understanding of the pathogenesis of cholangiocarcinoma sarcoma.展开更多
Background Most existing chemical experiment teaching systems lack solid immersive experiences,making it difficult to engage students.To address these challenges,we propose a chemical simulation teaching system based ...Background Most existing chemical experiment teaching systems lack solid immersive experiences,making it difficult to engage students.To address these challenges,we propose a chemical simulation teaching system based on virtual reality and gesture interaction.Methods The parameters of the models were obtained through actual investigation,whereby Blender and 3DS MAX were used to model and import these parameters into a physics engine.By establishing an interface for the physics engine,gesture interaction hardware,and virtual reality(VR)helmet,a highly realistic chemical experiment environment was created.Using code script logic,particle systems,as well as other systems,chemical phenomena were simulated.Furthermore,we created an online teaching platform using streaming media and databases to address the problems of distance teaching.Results The proposed system was evaluated against two mainstream products in the market.In the experiments,the proposed system outperformed the other products in terms of fidelity and practicality.Conclusions The proposed system which offers realistic simulations and practicability,can help improve the high school chemistry experimental education.展开更多
Qaidam Basin in Qinghai Province has rich multiple complex resources with salt lakes as the core.These resources form a special condition for the development of green economy,having rare and particular nature.The
Treatment of terminal system is mainly through the interface communication protocol for treatment planningsystem to achieve the control of various kinds of medical equipments, including primary collimator, range shift...Treatment of terminal system is mainly through the interface communication protocol for treatment planningsystem to achieve the control of various kinds of medical equipments, including primary collimator, range shifter,scatterer, ridge type filter, multi-leaf collimator, etc. TPS was based on the radioactive source and the patientmodeling to simulate the plan implementation of radiotherapy. The basic structure of block diagram is shown inFig. 1.展开更多
On Februar 22~(nd),2021,the State Councilissued Guiding Opinions on Accelerating the Establishment and Improvement of Green and Low-carbon Circular Economic System(hereinafter referred to as the Guiding Opinions)Accor...On Februar 22~(nd),2021,the State Councilissued Guiding Opinions on Accelerating the Establishment and Improvement of Green and Low-carbon Circular Economic System(hereinafter referred to as the Guiding Opinions)According to the Guiding Opinions, establishing and improving the country's green.展开更多
Good crop stand establishment and root system development are essential for optimum grain yield of dryland wheat (Triti-cum aestivumL.). At present, little is known about the effect of tilage and straw mulch on the ...Good crop stand establishment and root system development are essential for optimum grain yield of dryland wheat (Triti-cum aestivumL.). At present, little is known about the effect of tilage and straw mulch on the root system of wheat under dryland areas in southwestern China. The aim of this study was to evaluate the effect of three tilage treatments (no-til, NT; rotary til, RT; conventional til, CT) and two crop residue management practices (straw mulch, ML; non-straw mulch, NML) on stand establishment, root growth and grain yield of wheat. NT resulted in lower soil cover thickness for the wheat seed, higher number of uncovered seeds, lower percentage of seedling-less ridges and lower tiler density compared to RT and CT; ML resulted in higher tiler density compared to NML. Straw mulching resulted in more soil water content and root length density (RLD) at most of the growth stages and soil depths. The maximum RLD, root surface area density and root dry matter density were obtained under NT. In the topmost 10 cm soil layer, higher RLD values were found under NT than those under RT and CT. There were no signiifcant differences in the yield or yield components of wheat among the tilage treatments in 2011–2012, but NT resulted in a signiifcant higher yield compared to RT and CT in 2012–2013. Grain yield was signiifcantly higher in ML compared to in NML. A strong relationship was observed between the water-use efifciency and the grain yield. Both NT and ML proved beneifcial for wheat in term of maintaining higher tiler density, better soil water status and root growth, leading to a higher grain yield and enhanced water-use efifciency, especialy in a low rainfal year.展开更多
The area around the oasis, lying between the oasis and the natural desert and encirclesthe oasis is different from ecotone of the oasis and the desert, because it is not the trans-forming area betwen them, but it is e...The area around the oasis, lying between the oasis and the natural desert and encirclesthe oasis is different from ecotone of the oasis and the desert, because it is not the trans-forming area betwen them, but it is ecological rift valley or ecological burst zone. The oasisbase will be shaked and the nature desert will be degenerative too. It is the crux of the envi-展开更多
Medication-related osteonecrosis of the jaw(MRONJ)is primarily associated with administering antiresorptive or antiangiogenic drugs.Despite significant research on MRONJ,its pathogenesis and effective treatments are s...Medication-related osteonecrosis of the jaw(MRONJ)is primarily associated with administering antiresorptive or antiangiogenic drugs.Despite significant research on MRONJ,its pathogenesis and effective treatments are still not fully understood.Animal models can be used to simulate the pathophysiological features of MRONJ,serving as standardized in vivo experimental platforms to explore the pathogenesis and therapies of MRONJ.Rodent models exhibit excellent effectiveness and high reproducibility in mimicking human MRONJ,but classical methods cannot achieve a complete replica of the pathogenesis of MRONJ.Modified rodent models have been reported with improvements for better mimicking of MRONJ onset in clinic.This review summarizes representative classical and modified rodent models of MRONJ created through various combinations of systemic drug induction and local stimulation and discusses their effectiveness and efficiency.Currently,there is a lack of a unified assessment system for MRONJ models,which hinders a standard definition of MRONJ-like lesions in rodents.Therefore,this review comprehensively summarizes assessment systems based on published peer-review articles,including new approaches in gross observation,histological assessments,radiographic assessments,and serological assessments.This review can serve as a reference for model establishment and evaluation in future preclinical studies on MRONJ.展开更多
Lung cancer is the leading cause of cancer mortality worldwide.Even with the applications of excision, radiotherapy, chemotherapy, and gene therapy, the 5 year survival rate is only 15% in the USA. Clinically relevant...Lung cancer is the leading cause of cancer mortality worldwide.Even with the applications of excision, radiotherapy, chemotherapy, and gene therapy, the 5 year survival rate is only 15% in the USA. Clinically relevant laboratory animal models of the disease could greatly facilitate understanding of the pathogenesis of lung cancer, its progression, invasion and metastasis. Transplanted lung cancer models are of special interest and are widely used today. Such models are essential tools in accelerating development of new therapies for lung cancer. In this communication we will present a brief overview of the hosts, sites and pathways used to establish transplanted animal lung tumor models.展开更多
In the paper, the establishment, measurement, data-processing program and monitoring accuracy of the GPS seismic monitoring network in North China, especially in the Capital-Circle area, have been presented briefly. T...In the paper, the establishment, measurement, data-processing program and monitoring accuracy of the GPS seismic monitoring network in North China, especially in the Capital-Circle area, have been presented briefly. The relation of horizontal crustal deformation to tectonic movement, stress-field variation and seismicity has been analyzed in detail. The results indicate that the accuracy of GPS measurement has reached the order of 10-9 and the annual rate of horizontal crustal deformation in North China is about 4 ~5 mm. Horizontal crustal movement is a direct indication of the regional stress field. Therefore, by monitoring the time-sequence variation of horizontal crustal motion, it would be possible to investigate the change in the stress field, to analyze the tendency of seismicity and to determine the seismogenic zones.展开更多
Early bacterial colonization and succession within the gastrointestinal tract have been suggested to be crucial in the development of host immunity.In this study,we have investigated the changes in live weight and con...Early bacterial colonization and succession within the gastrointestinal tract have been suggested to be crucial in the development of host immunity.In this study,we have investigated the changes in live weight and concentrations of selected serum parameters in relation to their fecal bacterial communities as determined by high throughput sequencing of the 16S r RNA gene over the same period in lambs.The results showed that lambs’growth performance,the serum parameters,fecal bacterial community and fecal bacterial functions were all affected(P<0.05)by age of the lambs.Similarity within age groups of fecal microbiota was lower in the preweaning period and increased sharply(P<0.05)after weaning at 60 days.The similarity between the samples collected from birth to 90 days of age and those collected at 120 days of age,increased(P<0.05)sharply after 30 days of age.Some age-associated changes in microbial genera were correlated with the changes in concentrations of immune indicators,including negative(P<0.05)correlations between the relative abundance of Lachnospiraceae UCG-010,Eubacterium coprostanoligenes group,Ruminococcaceae UCG-005,Ruminococcaceae UCG-009,Ruminococcaceae UCG-013,Ruminiclostridium 6,Ruminococcaceae UCG-008,and Oscillibacter with serum concentrations of lipopolysaccharide(LPS),D-lactate dehydrogenase(DLA),immunoglobulin(IgA,IgM,and IgG),and cytokines(interleukin-1β(IL-1β),IL-6,IL-12,and IL-17),tumor necrosis factor-α(TNF-α),and the relative abundance of these genera increased from 45 days of age.In conclusion,these results suggested that the age-related abundances of particular genera were correlated with serum markers of immunity in lambs,and there might be a critical window in the period from birth to 45 days of age which provide an opportunity for potential manipulation of the fecal microbial ecosystems to enhance immune function.展开更多
Frost heaving processes have been a focus of study since the late 19th century.Factors controlling frost heave development were investigated over several decades.The mechanisms involved were identified based on numero...Frost heaving processes have been a focus of study since the late 19th century.Factors controlling frost heave development were investigated over several decades.The mechanisms involved were identified based on numerous field and experimental evidences. However,despite this long history of frost展开更多
Background:Influenza is an acute respiratory infectious disease with a high incidence rate in the Chinese army,which directly disturbs military training and affects soldiers’health.Influenza surveillance systems are ...Background:Influenza is an acute respiratory infectious disease with a high incidence rate in the Chinese army,which directly disturbs military training and affects soldiers’health.Influenza surveillance systems are widely used around the world and play an important role in influenza epidemic prevention and control.Methods:As a theater centers for disease prevention and control,we established an influenza monitoring platform(IMP)in 2014 to strengthen the monitoring of influenza-like illness and influenza virus infection.In this study,we introduced the constitution,influenza virus detection,and quality control for an IMP.The monitoring effect was also evaluated by comparing the monitoring data with data from national influenza surveillance systems.The experiences and problems associated with the platform also were summarized.Results:A theater IMP was established based on 3 levels of medical units,including monitoring sites,testing laboratories and a checking laboratory.A series of measures were taken to guarantee the quality of monitoring,such as technical training,a unified process,sufficient supervision and timely communication.The platform has run smoothly for 3 monitoring years to date.In the 2014–2015 and 2016–2017 monitoring years,sample amount coincided with that obtained from the National Influenza Surveillance program.In the 2015–2016 monitoring year,due to the strict prevention and control measures,an influenza epidemic peak was avoided in monitoring units,and the monitoring data did not coincide with that of the National Influenza Surveillance program.Several problems,including insufficient attention,unreasonable administrative intervention or subordination relationships,and the necessity of detection in monitoring sites were still observed.Conclusion:A theater IMP was established rationally and played a deserved role in the prevention and control of influenza.However,several problems remain to be solved.展开更多
since the establishment of the People’s Republic of China,the central leader-groups from generation to generation have been continuously exploring and innovating Marxist political party theory in terms of its value t...since the establishment of the People’s Republic of China,the central leader-groups from generation to generation have been continuously exploring and innovating Marxist political party theory in terms of its value target,ideological construction,working style,and organization developments.This process can be categorized into five stages:the founding stage in Mao Zedong’s era,the development stage in Deng Xiaoping’s ear,the promotion stage in Jiang Zemin’s times,the deepening stage under Hu Jintao’s leadership,and the stage of further innovation by Xi Jinping in the new era,with the characteristics of inheritance,development as well as scientificity and valuation.展开更多
Most intestinal parasites are cosmopolitan with the highest prevalence in the tropics and subtopics. Rural-to-urban migration rapidly increases the number of food eating places in towns and their environs. Some of the...Most intestinal parasites are cosmopolitan with the highest prevalence in the tropics and subtopics. Rural-to-urban migration rapidly increases the number of food eating places in towns and their environs. Some of these eating estabishments have poor sanitation and are overcrowded, facilitating disease transmission, especially through food-handling. Our investigations in Nairobi, therefore, were set to determine the presence of intestinal parasites in food-handlers with valid medical certificates. Direct and concentrated stool processing techniques were used. Chisquare test and ANOVA were used for data analysis. The parasites Ascaris lumbricoides, Entamoeba histolytica and Giardia lamblia were observed in certified food-handlers. Significant difference was found in parasite frequency by eating classes and gender (χ^2 = 9.49, P = 0.73), (F = 1.495, P = 0.297), but not in parasite occurrence between age brackets (χ^2 = 6.99, P = 0.039). The six-month medical certificate validity period may contribute significantly to the presence of intestinal parasites in certified food-handlers.展开更多
This article expounds the economic characteristics of circular agricultural technology.Since the circular agricultural technology has characteristics and externality of public goods,the government participation is nec...This article expounds the economic characteristics of circular agricultural technology.Since the circular agricultural technology has characteristics and externality of public goods,the government participation is necessary in building the technology system of circular agriculture,in order to avoid "free rider" behavior in the consumption of public goods and internalize externality.We analyze the orientation of government's role in building the technology system of circular agriculture:the government is the leader,designer,organizer and regulator in building the technology system of circular agriculture;the government orientates the four roles precisely in building the technology system of circular agriculture,to ensure that they do not cross the line,but be indispensable all the while.展开更多
The wax palm (Ceroxylon echinulatum) and palm heart (Prestoea acuminata) are key elements in Andean natural forests. This ecosystem is threatened by deforestation and habitat degradation, thus, it is vital to explore ...The wax palm (Ceroxylon echinulatum) and palm heart (Prestoea acuminata) are key elements in Andean natural forests. This ecosystem is threatened by deforestation and habitat degradation, thus, it is vital to explore the impact of anthropogenic activities on the ecological structure and preferences of these species in order to develop proper conservation strategies. Fifty-seven 400 m2 plots were established in two forest areas, a disturbed forest (n = 30 plots) and an undisturbed forest (n = 27 plots) in the Ecuadorean Andes. Nine micro-environmental variables and the number of individuals of C. echinulatum and P. acuminata in five size classes were recorded in each plot. Logistic regression models helped identify environmental variables that influence the establishment of the species. Results showed that different micro-environmental variables determined the presence of different size classes. Both species were benefitted by the environmental conditions of the disturbed forest. Light availability was important for the establishment of both species, especially for the canopy species (C. echinulatum). This palm was negatively affected by the variable “fallen wood”, while P. acuminata was negatively affected mainly by the steepness of the terrain. The environmental variables for the successful establishment of the studied species that were identified by this study provide clues for the sustainable management of C. echinulatum and P. acuminata in Andean forests.展开更多
基金the National Natural Science Foundation of China,No.82060551and Lanzhou Chengguan District Science and Technology Planning Project,No.2019JSCX0092.
文摘BACKGROUND Extrahepatic cholangiocarcinoma sarcoma is extremely rare in clinical practice.These cells consist of both epithelial and mesenchymal cells.Patient-derived cell lines that maintain tumor characteristics are valuable tools for studying the molecular mechanisms associated with carcinosarcoma.However,cholangiocarcinoma sarcoma cell lines are not available in cell banks.AIM To establish and characterize a new extrahepatic cholangiocarcinoma sarcoma cell line,namely CBC2T-2.METHODS We conducted a short tandem repeat(STR)test to confirm the identity of the CBC2T-2 cell line.Furthermore,we assessed the migratory and invasive properties of the cells and performed clonogenicity assay to evaluate the ability of individual cells to form colonies.The tumorigenic potential of CBC2T-2 cells was tested in vivo using nonobese diabetic/severe combined immunodeficient(NOD/SCID)mice.The cells were injected subcutaneously and tumor formation was observed.In addition,immunohistochemical analysis was carried out to examine the expression of epithelial marker CK19 and mesenchymal marker vimentin in both CBC2T-2 cells and xenografts.The CBC2T-2 cell line was used to screen the potential therapeutic effects of various clinical agents in patients with cholangiocarcinoma sarcoma.Lastly,whole-exome sequencing was performed to identify genetic alterations and screen for somatic mutations in the CBC2T-2 cell line.RESULTS The STR test showed that there was no cross-contamination and the results were identical to those of the original tissue.The cells showed round or oval-shaped epithelioid cells and mesenchymal cells with spindle-shaped or elongated morphology.The cells exhibited a high proliferation ratio with a doubling time of 47.11 h.This cell line has migratory,invasive,and clonogenic abilities.The chromosomes in the CBC2T-2 cells were polyploidy,with numbers ranging from 69 to 79.The subcutaneous tumorigenic assay confirmed the in vivo tumorigenic ability of CBC2T-2 cells in NOD/SCID mice.CBC2T-2 cells and xenografts were positive for both the epithelial marker,CK19,and the mesenchymal marker,vimentin.These results suggest that CBC2T-2 cells may have both epithelial and mesenchymal characteristics.The cells were also used to screen clinical agents in patients with cholangiocarcinoma sarcoma,and a combination of paclitaxel and gemcitabine was found to be the most effective treatment option.CONCLUSION We established the first human cholangiocarcinoma sarcoma cell line,CBC2T-2,with stable biogenetic traits.This cell line,as a research model,has a high clinical value and would facilitate the understanding of the pathogenesis of cholangiocarcinoma sarcoma.
基金National Innovation and Entrepreneurship Program for College Students(202218213001)Science and Technology Innovation Strategy of Guangdong Province(Science and Technology Innovation Cultivation of University Students 2020329182130C000002).
文摘Background Most existing chemical experiment teaching systems lack solid immersive experiences,making it difficult to engage students.To address these challenges,we propose a chemical simulation teaching system based on virtual reality and gesture interaction.Methods The parameters of the models were obtained through actual investigation,whereby Blender and 3DS MAX were used to model and import these parameters into a physics engine.By establishing an interface for the physics engine,gesture interaction hardware,and virtual reality(VR)helmet,a highly realistic chemical experiment environment was created.Using code script logic,particle systems,as well as other systems,chemical phenomena were simulated.Furthermore,we created an online teaching platform using streaming media and databases to address the problems of distance teaching.Results The proposed system was evaluated against two mainstream products in the market.In the experiments,the proposed system outperformed the other products in terms of fidelity and practicality.Conclusions The proposed system which offers realistic simulations and practicability,can help improve the high school chemistry experimental education.
文摘Qaidam Basin in Qinghai Province has rich multiple complex resources with salt lakes as the core.These resources form a special condition for the development of green economy,having rare and particular nature.The
文摘Treatment of terminal system is mainly through the interface communication protocol for treatment planningsystem to achieve the control of various kinds of medical equipments, including primary collimator, range shifter,scatterer, ridge type filter, multi-leaf collimator, etc. TPS was based on the radioactive source and the patientmodeling to simulate the plan implementation of radiotherapy. The basic structure of block diagram is shown inFig. 1.
文摘On Februar 22~(nd),2021,the State Councilissued Guiding Opinions on Accelerating the Establishment and Improvement of Green and Low-carbon Circular Economic System(hereinafter referred to as the Guiding Opinions)According to the Guiding Opinions, establishing and improving the country's green.
基金supported by the China Agriculture Research System(CARS-3)the Public Welfare Industry(Agriculture)Scientific Research of China(200903010-06)
文摘Good crop stand establishment and root system development are essential for optimum grain yield of dryland wheat (Triti-cum aestivumL.). At present, little is known about the effect of tilage and straw mulch on the root system of wheat under dryland areas in southwestern China. The aim of this study was to evaluate the effect of three tilage treatments (no-til, NT; rotary til, RT; conventional til, CT) and two crop residue management practices (straw mulch, ML; non-straw mulch, NML) on stand establishment, root growth and grain yield of wheat. NT resulted in lower soil cover thickness for the wheat seed, higher number of uncovered seeds, lower percentage of seedling-less ridges and lower tiler density compared to RT and CT; ML resulted in higher tiler density compared to NML. Straw mulching resulted in more soil water content and root length density (RLD) at most of the growth stages and soil depths. The maximum RLD, root surface area density and root dry matter density were obtained under NT. In the topmost 10 cm soil layer, higher RLD values were found under NT than those under RT and CT. There were no signiifcant differences in the yield or yield components of wheat among the tilage treatments in 2011–2012, but NT resulted in a signiifcant higher yield compared to RT and CT in 2012–2013. Grain yield was signiifcantly higher in ML compared to in NML. A strong relationship was observed between the water-use efifciency and the grain yield. Both NT and ML proved beneifcial for wheat in term of maintaining higher tiler density, better soil water status and root growth, leading to a higher grain yield and enhanced water-use efifciency, especialy in a low rainfal year.
文摘The area around the oasis, lying between the oasis and the natural desert and encirclesthe oasis is different from ecotone of the oasis and the desert, because it is not the trans-forming area betwen them, but it is ecological rift valley or ecological burst zone. The oasisbase will be shaked and the nature desert will be degenerative too. It is the crux of the envi-
基金supported by the National Natural Science Foundation of China(No.81921002,No.81900970)Young Physician Innovation Team Project(No.QC202003)from Ninth People’s Hospital,Shanghai Jiao Tong University School of MedicineShanghai Sailing Program(19YF1426000)jointly。
文摘Medication-related osteonecrosis of the jaw(MRONJ)is primarily associated with administering antiresorptive or antiangiogenic drugs.Despite significant research on MRONJ,its pathogenesis and effective treatments are still not fully understood.Animal models can be used to simulate the pathophysiological features of MRONJ,serving as standardized in vivo experimental platforms to explore the pathogenesis and therapies of MRONJ.Rodent models exhibit excellent effectiveness and high reproducibility in mimicking human MRONJ,but classical methods cannot achieve a complete replica of the pathogenesis of MRONJ.Modified rodent models have been reported with improvements for better mimicking of MRONJ onset in clinic.This review summarizes representative classical and modified rodent models of MRONJ created through various combinations of systemic drug induction and local stimulation and discusses their effectiveness and efficiency.Currently,there is a lack of a unified assessment system for MRONJ models,which hinders a standard definition of MRONJ-like lesions in rodents.Therefore,this review comprehensively summarizes assessment systems based on published peer-review articles,including new approaches in gross observation,histological assessments,radiographic assessments,and serological assessments.This review can serve as a reference for model establishment and evaluation in future preclinical studies on MRONJ.
文摘Lung cancer is the leading cause of cancer mortality worldwide.Even with the applications of excision, radiotherapy, chemotherapy, and gene therapy, the 5 year survival rate is only 15% in the USA. Clinically relevant laboratory animal models of the disease could greatly facilitate understanding of the pathogenesis of lung cancer, its progression, invasion and metastasis. Transplanted lung cancer models are of special interest and are widely used today. Such models are essential tools in accelerating development of new therapies for lung cancer. In this communication we will present a brief overview of the hosts, sites and pathways used to establish transplanted animal lung tumor models.
文摘In the paper, the establishment, measurement, data-processing program and monitoring accuracy of the GPS seismic monitoring network in North China, especially in the Capital-Circle area, have been presented briefly. The relation of horizontal crustal deformation to tectonic movement, stress-field variation and seismicity has been analyzed in detail. The results indicate that the accuracy of GPS measurement has reached the order of 10-9 and the annual rate of horizontal crustal deformation in North China is about 4 ~5 mm. Horizontal crustal movement is a direct indication of the regional stress field. Therefore, by monitoring the time-sequence variation of horizontal crustal motion, it would be possible to investigate the change in the stress field, to analyze the tendency of seismicity and to determine the seismogenic zones.
基金supported by the China Agriculture Research System(CARS-38)the National Key Research&Development Program of China(2018YFD0502100)the Scientific Research Foundation of Hebei Agricultural University,China(YJ201825)。
文摘Early bacterial colonization and succession within the gastrointestinal tract have been suggested to be crucial in the development of host immunity.In this study,we have investigated the changes in live weight and concentrations of selected serum parameters in relation to their fecal bacterial communities as determined by high throughput sequencing of the 16S r RNA gene over the same period in lambs.The results showed that lambs’growth performance,the serum parameters,fecal bacterial community and fecal bacterial functions were all affected(P<0.05)by age of the lambs.Similarity within age groups of fecal microbiota was lower in the preweaning period and increased sharply(P<0.05)after weaning at 60 days.The similarity between the samples collected from birth to 90 days of age and those collected at 120 days of age,increased(P<0.05)sharply after 30 days of age.Some age-associated changes in microbial genera were correlated with the changes in concentrations of immune indicators,including negative(P<0.05)correlations between the relative abundance of Lachnospiraceae UCG-010,Eubacterium coprostanoligenes group,Ruminococcaceae UCG-005,Ruminococcaceae UCG-009,Ruminococcaceae UCG-013,Ruminiclostridium 6,Ruminococcaceae UCG-008,and Oscillibacter with serum concentrations of lipopolysaccharide(LPS),D-lactate dehydrogenase(DLA),immunoglobulin(IgA,IgM,and IgG),and cytokines(interleukin-1β(IL-1β),IL-6,IL-12,and IL-17),tumor necrosis factor-α(TNF-α),and the relative abundance of these genera increased from 45 days of age.In conclusion,these results suggested that the age-related abundances of particular genera were correlated with serum markers of immunity in lambs,and there might be a critical window in the period from birth to 45 days of age which provide an opportunity for potential manipulation of the fecal microbial ecosystems to enhance immune function.
文摘Frost heaving processes have been a focus of study since the late 19th century.Factors controlling frost heave development were investigated over several decades.The mechanisms involved were identified based on numerous field and experimental evidences. However,despite this long history of frost
文摘Background:Influenza is an acute respiratory infectious disease with a high incidence rate in the Chinese army,which directly disturbs military training and affects soldiers’health.Influenza surveillance systems are widely used around the world and play an important role in influenza epidemic prevention and control.Methods:As a theater centers for disease prevention and control,we established an influenza monitoring platform(IMP)in 2014 to strengthen the monitoring of influenza-like illness and influenza virus infection.In this study,we introduced the constitution,influenza virus detection,and quality control for an IMP.The monitoring effect was also evaluated by comparing the monitoring data with data from national influenza surveillance systems.The experiences and problems associated with the platform also were summarized.Results:A theater IMP was established based on 3 levels of medical units,including monitoring sites,testing laboratories and a checking laboratory.A series of measures were taken to guarantee the quality of monitoring,such as technical training,a unified process,sufficient supervision and timely communication.The platform has run smoothly for 3 monitoring years to date.In the 2014–2015 and 2016–2017 monitoring years,sample amount coincided with that obtained from the National Influenza Surveillance program.In the 2015–2016 monitoring year,due to the strict prevention and control measures,an influenza epidemic peak was avoided in monitoring units,and the monitoring data did not coincide with that of the National Influenza Surveillance program.Several problems,including insufficient attention,unreasonable administrative intervention or subordination relationships,and the necessity of detection in monitoring sites were still observed.Conclusion:A theater IMP was established rationally and played a deserved role in the prevention and control of influenza.However,several problems remain to be solved.
文摘since the establishment of the People’s Republic of China,the central leader-groups from generation to generation have been continuously exploring and innovating Marxist political party theory in terms of its value target,ideological construction,working style,and organization developments.This process can be categorized into five stages:the founding stage in Mao Zedong’s era,the development stage in Deng Xiaoping’s ear,the promotion stage in Jiang Zemin’s times,the deepening stage under Hu Jintao’s leadership,and the stage of further innovation by Xi Jinping in the new era,with the characteristics of inheritance,development as well as scientificity and valuation.
文摘Most intestinal parasites are cosmopolitan with the highest prevalence in the tropics and subtopics. Rural-to-urban migration rapidly increases the number of food eating places in towns and their environs. Some of these eating estabishments have poor sanitation and are overcrowded, facilitating disease transmission, especially through food-handling. Our investigations in Nairobi, therefore, were set to determine the presence of intestinal parasites in food-handlers with valid medical certificates. Direct and concentrated stool processing techniques were used. Chisquare test and ANOVA were used for data analysis. The parasites Ascaris lumbricoides, Entamoeba histolytica and Giardia lamblia were observed in certified food-handlers. Significant difference was found in parasite frequency by eating classes and gender (χ^2 = 9.49, P = 0.73), (F = 1.495, P = 0.297), but not in parasite occurrence between age brackets (χ^2 = 6.99, P = 0.039). The six-month medical certificate validity period may contribute significantly to the presence of intestinal parasites in certified food-handlers.
文摘This article expounds the economic characteristics of circular agricultural technology.Since the circular agricultural technology has characteristics and externality of public goods,the government participation is necessary in building the technology system of circular agriculture,in order to avoid "free rider" behavior in the consumption of public goods and internalize externality.We analyze the orientation of government's role in building the technology system of circular agriculture:the government is the leader,designer,organizer and regulator in building the technology system of circular agriculture;the government orientates the four roles precisely in building the technology system of circular agriculture,to ensure that they do not cross the line,but be indispensable all the while.
文摘The wax palm (Ceroxylon echinulatum) and palm heart (Prestoea acuminata) are key elements in Andean natural forests. This ecosystem is threatened by deforestation and habitat degradation, thus, it is vital to explore the impact of anthropogenic activities on the ecological structure and preferences of these species in order to develop proper conservation strategies. Fifty-seven 400 m2 plots were established in two forest areas, a disturbed forest (n = 30 plots) and an undisturbed forest (n = 27 plots) in the Ecuadorean Andes. Nine micro-environmental variables and the number of individuals of C. echinulatum and P. acuminata in five size classes were recorded in each plot. Logistic regression models helped identify environmental variables that influence the establishment of the species. Results showed that different micro-environmental variables determined the presence of different size classes. Both species were benefitted by the environmental conditions of the disturbed forest. Light availability was important for the establishment of both species, especially for the canopy species (C. echinulatum). This palm was negatively affected by the variable “fallen wood”, while P. acuminata was negatively affected mainly by the steepness of the terrain. The environmental variables for the successful establishment of the studied species that were identified by this study provide clues for the sustainable management of C. echinulatum and P. acuminata in Andean forests.