期刊文献+
共找到342,174篇文章
< 1 2 250 >
每页显示 20 50 100
Identification of TNFRSF1A as a novel regulator of carfilzomib resistance in multiple myeloma
1
作者 JIE ZHAO XUANTAO YANG +1 位作者 HAIXI ZHANG XUEZHONG GU 《Oncology Research》 SCIE 2024年第2期325-337,共13页
Multiple myeloma(MM)is a hematological tumor with high mortality and recurrence rate.Carfilzomib is a new-generation proteasome inhibitor that is used as the first-line therapy for MM.However,the development of drug r... Multiple myeloma(MM)is a hematological tumor with high mortality and recurrence rate.Carfilzomib is a new-generation proteasome inhibitor that is used as the first-line therapy for MM.However,the development of drug resistance is a pervasive obstacle to treating MM.Therefore,elucidating the drug resistance mechanisms is conducive to the formulation of novel therapeutic therapies.To elucidate the mechanisms of carfilzomib resistance,we retrieved the GSE78069 microarray dataset containing carfilzomib-resistant LP-1 MM cells and parental MM cells.Differential gene expression analyses revealed major alterations in the major histocompatibility complex(MHC)and cell adhesion molecules.The upregulation of the tumor necrosis factor(TNF)receptor superfamily member 1A(TNFRSF1A)gene was accompanied by the downregulation of MHC genes and cell adhesion molecules.Furthermore,to investigate the roles of these genes,we established a carfilzomib-resistant cell model and observed that carfilzomib resistance induced TNFRSF1A overexpression and TNFRSF1A silencing reversed carfilzomib resistance and reactivated the expression of cell adhesion molecules.Furthermore,TNFRSF1A silencing suppressed the tumorigenesis of MM cells in immunocompetent mice,indicating that TNFRSF1A may lead to carfilzomib resistance by dampening antitumor immunity.Furthermore,our results indicated that TNFRSF1A overexpression conferred carfilzomib resistance in MM cells and suppressed the expression of MHC genes and cell adhesion molecules.The suppression of MHC genes and cell adhesion molecules may impair the interaction between immune cells and cancer cells to impair antitumor immunity.Future studies are warranted to further investigate the signaling pathway underlying the regulatory role of TNFRSF1A in MM cells. 展开更多
关键词 multiple myeloma Carfilzomib Drug resistance Major histocompatibility complex TNFRSF1A
下载PDF
Pyramiding of multiple genes generates rapeseed introgression lines with clubroot and herbicide resistance, high oleic acid content, and early maturity
2
作者 Zhaoyang Wang Fucai Wang +6 位作者 Zihan Yu Xiaorui Shi Xianming Zhou Pengfei Wang Yixian Song Dengfeng Hong Guangsheng Yang 《The Crop Journal》 SCIE CSCD 2023年第3期895-903,共9页
Clubroot and herbicide resistance,high oleic acid(OA)content,and early maturity are targets of rapeseed(Brassica napus L.)breeding.The objective of this study was to develop new male-fertility restorer lines by pyrami... Clubroot and herbicide resistance,high oleic acid(OA)content,and early maturity are targets of rapeseed(Brassica napus L.)breeding.The objective of this study was to develop new male-fertility restorer lines by pyramiding favorable genes to improve these traits simultaneously.Seven elite alleles for the four traits were introduced into the restorer line 621R by speed breeding with marker-assisted and phenotypic selection.Six introgression lines(ILs)were developed with four-to seven-gene combinations and crossed with two elite parents to develop hybrids.All ILs and their corresponding hybrids displayed high resistance to both clubroot pathotype 4 and sulfonylurea herbicides.Three ILs and their hybrids showed large increases in OA contents and four showed earlier maturity.These new ILs may be useful in rapeseed hybrid breeding for the target traits. 展开更多
关键词 Clubroot resistance Herbicide resistance Oleic acid content Flowering time Pyramid breeding
下载PDF
Study of energy-efficient heat resistance and cooling technology for high temperature working face with multiple heat sources in deep mine
3
作者 Hongbin Zhao Shihao Tu +2 位作者 Xun Liu Jieyang Ma Long Tang 《International Journal of Coal Science & Technology》 EI CAS CSCD 2023年第3期92-107,共16页
In the present research,we proposed a scheme to address the issues of severe heat damage,high energy consumption,low cooling system efficiency,and wastage of cold capacity in mines.To elucidate the seasonal variations... In the present research,we proposed a scheme to address the issues of severe heat damage,high energy consumption,low cooling system efficiency,and wastage of cold capacity in mines.To elucidate the seasonal variations of environmental temperature through field measurements,we selected a high-temperature working face in a deep mine as our engineering background.To enhance the heat damage control cability of the working face and minimize unnecessary cooling capac-ity loss,we introduced the multi-dimensional heat hazard prevention and control method called"Heat source barrier and cooling equipment".First,we utilize shotcrete and liquid nitrogen injection to eliminate the heat source and implemented pressure equalization ventilation to disrupt the heat transfer path,thereby creating a heat barrier.Second,we establish divi-sional prediction models for airflow temperature based on the variation patterns obtained through numerical simulation.Third,we devise the location and dynamic control strategy for the cooling equipment based on the prediction models.The results of field application show that the heat resistance and cooling linkage method comply with the safety requirement throughout the entire mining cycle while effectively reducing energy consumption.The ambient temperature is maintained below 30℃,resulting in the energy saving of 10%during the high-temperature period and over 50%during the low-temperature period.These findings serve as a valuable reference for managing heat damage in high-temperature working faces. 展开更多
关键词 High-temperature working face Heat source barrier multiple heat source effect Airflow temperature prediction Dynamic control strategy
下载PDF
Suppression of P-gp induced multiple drug resistance in a drug resistant gastric cancer cell line by overexpression of Fas 被引量:24
4
作者 Yin F Shi YQ +3 位作者 Zhao WP Xiao B Miao JY Fan DM 《World Journal of Gastroenterology》 SCIE CAS CSCD 2000年第5期664-670,共7页
AIM To observe the drug sensitizing effect andrelated mechanisms of fas gene transduction onhuman drug-resistant gastric cancer cellSGC7901/VCR(resistant to Vincristine).METHODS The cell cycle alteration wasobserved b... AIM To observe the drug sensitizing effect andrelated mechanisms of fas gene transduction onhuman drug-resistant gastric cancer cellSGC7901/VCR(resistant to Vincristine).METHODS The cell cycle alteration wasobserved by FACS.The sensitivity of gastriccancer cells to apoptosis was determined by invitro apoptosis assay.The drug sensitization ofcells to several anti-tumor drugs was observedby MTT assay.Immunochemical method wasused to show expression of P-gp and Topo Ⅱ ingastric cancer cells.RESULTS Comparing to SGC7901 and pBK-SGC7901/VCR,fas-SGC7901/VCR showeddecreasing G2 cells and increasing S cells,theG2 phase fraction of pBK-SGC7901/VCR wasabout 3.0 times that of fas-SGC7901/VCR,but Sphase fraction of fas-SGC7901/VCR was about1.9 times that of pBK-SGC7901/VCR,indicatingS phase arrest of fas-SGC7901/VCR.FACS alsosuggested apoptosis of fas-SGC7901/VCR,fas-SGC7901/VCR was more sensitive to apoptosisinducing agent VM-26 than pBK-SGC7901/VCR.MTT assay showed increased sensitization offas-SGC7901/VCR to DDP,MMC and 5-FU,butsame sensitization to VCR according to pBK-SGC7901/VCR.SGC7901,pBK-SGC7901/ VCRand fas-SGC7901/VCR had positively stainedTopo Ⅱ equally.P-gp staining in pBK- SGC7901/VCR was stronger than in SG07901,but there was little staining of P-gp in fas.SGC7901/VCR.CONCLUSION fas gene transduction couldreverse the MDR of human drug-resistant gastriccancer cell SGC7901/VCR to a degree,possiblybecause of higher sensitization to apoptosis anddecreased expression of P-gp. 展开更多
关键词 FAS GENE STOMACH neoplasms apoptosis drug resistance multiple ANTINEOPLASTIC agents immunocytochemistry/methods GENE TRANSDUCTION
下载PDF
Novel mechanism of drug resistance to proteasome inhibitors in multiple myeloma 被引量:3
5
作者 Jianbiao Zhou Wee-Joo Chng 《World Journal of Clinical Oncology》 CAS 2019年第9期303-306,共4页
Multiple myeloma(MM) is a cancer caused by uncontrolled proliferation of antibody-secreting plasma cells in bone marrow, which represents the second most common hematological malignancy. MM is a highly heterogeneous d... Multiple myeloma(MM) is a cancer caused by uncontrolled proliferation of antibody-secreting plasma cells in bone marrow, which represents the second most common hematological malignancy. MM is a highly heterogeneous disease and can be classified into a spectrum of subgroups based on their molecular and cytogenetic abnormalities. In the past decade, novel therapies, especially, the first-in-class proteasome inhibitor bortezomib, have been revolutionary for the treatment of MM patients. Despite these remarkable achievements, myeloma remains incurable with a high frequency of patients suffering from a relapse, due to drug resistance. Mutation in the proteasome β5-subunit(PSMB5) was found in a bortezomib-resistant cell line generated via long-term coculture with increasing concentrations of bortezomib in 2008, but their actual implication in drug resistance in the clinic has not been reported until recently. A recent study discovered four resistance-inducing PSMB5 mutations from a relapsed MM patient receiving prolonged bortezomib treatment. Analysis of the dynamic clonal evolution revealed that two subclones existed at the onset of disease, while the other two subclones were induced. Protein structural modeling and functional assays demonstrated that all four mutations impaired the binding of bortezomib to the 20 S proteasome, conferring different degrees of resistance. The authors further demonstrated two potential approaches to overcome drug resistance by using combination therapy for targeting proteolysis machinery independent of the 20 S proteasome. 展开更多
关键词 multiple MYELOMA PROTEASOME inhibitor BORTEZOMIB PROTEASOME β5-subunit Drug resistance CLONAL evolution Combination therapy
下载PDF
A New High-throughput Real-time PCR Assay for the Screening of Multiple Antimicrobial Resistance Genes in Broiler Fecal Samples from China 被引量:2
6
作者 CHE Jie LU Jin Xing +6 位作者 LI Wen Ge ZHANG Yun Fei ZHAO Xiao Fei YUAN Min BAI Xue Mei CHEN Xia LI Juan 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 2019年第12期881-892,共12页
Objective Antimicrobial resistance(AMR)has become a global concern and is especially severe in China.To effectively and reliably provide AMR data,we developed a new high-throughput real-time PCR assay based on microfl... Objective Antimicrobial resistance(AMR)has become a global concern and is especially severe in China.To effectively and reliably provide AMR data,we developed a new high-throughput real-time PCR assay based on microfluidic dynamic technology,and screened multiple AMR genes in broiler fecal samples.Methods A high-throughput real-time PCR system with an new designed integrated fluidic circuit assay were performed AMR gene detection.A total of 273 broiler fecal samples collected from two geographically separated farms were screened AMR genes.Results The new assay with limits of detection ranging from 40.9 to 8,000 copies/reaction.The sensitivity rate,specificity rate,positive predictive value,negative predictive value and correct indices were 99.30%,98.08%,95.31%,99.79%,and 0.9755,respectively.Utilizing this assay,we demonstrate that AMR genes are widely spread,with positive detection rates ranging from 0 to 97.07%in 273 broiler fecal samples.bla CTX-M,bla TEM,mcr-1,fex A,cfr,optr A,and int I1 showed over 80%prevalence.The dissemination of AMR genes was distinct between the two farms.Conclusions We successfully established a new high-throughput real-time PCR assay applicable to AMR gene surveillance from fecal samples.The widespread existence of AMR genes detected in broiler farms highlights the current and severe problem of AMR. 展开更多
关键词 Antimicrobial resistance Antimicrobial resistance gene High-throughput real-time PCR array Broiler fecal sample
下载PDF
Insect resistance management in Bacillus thuringiensis cotton by MGPS(multiple genes pyramiding and silencing) 被引量:1
7
作者 ZAFAR Muhammad Mubashar RAZZAQ Abdul +5 位作者 FAROOQ Muhammad Awais REHMAN Abdul FIRDOUS Hina SHAKEEL Amir MO Huijuan REN Maozhi 《Journal of Cotton Research》 2020年第4期311-323,共13页
The introduction of Bacillus thuringiensis(Bt)cotton has reduced the burden of pests without harming the environment and human health.However,the efficacy of Bt cotton has decreased due to field-evolved resistance in ... The introduction of Bacillus thuringiensis(Bt)cotton has reduced the burden of pests without harming the environment and human health.However,the efficacy of Bt cotton has decreased due to field-evolved resistance in insect pests over time.In this review,we have discussed various factors that facilitate the evolution of resistance in cotton pests.Currently,different strategies like pyramided cotton expressing two or more distinct Bt toxin genes,refuge strategy,releasing of sterile insects,and gene silencing by RNAi are being used to control insect pests.Pyramided cotton has shown resistance against different cotton pests.The multiple genes pyramiding and silencing(MGPS)approach has been proposed for the management of cotton pests.The genome information of cotton pests is necessary for the development of MGPS-based cotton.The expression cassettes against various essential genes involved in defense,detoxification,digestion,and development of cotton pests will successfully obtain favorable agronomic characters for crop protection and production.The MGPS involves the construction of transformable artificial chromosomes,that can express multiple distinct Bt toxins and RNAi to knockdown various essential target genes to control pests.The evolution of resistance in cotton pests will be delayed or blocked by the synergistic action of high dose of Bt toxins and RNAi as well as compliance of refuge requirement. 展开更多
关键词 Bt cotton RNAI multiple genes pyramiding and silencing(MGPS) Bt resistance
下载PDF
Liposome-mediated Functional Expression of Multiple Drug Resistance Gene in Human Bone Marrow CD34^+ Cells
8
作者 曹文静 邹萍 《Journal of Huazhong University of Science and Technology(Medical Sciences)》 SCIE CAS 2004年第3期214-215,235,共3页
Summary: The expression and functional activity of multiple drug resistance (MDR1) gene in human normal bone marrow CD34+ cells was observed. Human normal bone marrow CD34+ cells were enriched with magnetic cell sorti... Summary: The expression and functional activity of multiple drug resistance (MDR1) gene in human normal bone marrow CD34+ cells was observed. Human normal bone marrow CD34+ cells were enriched with magnetic cell sorting (MACS) system, and then liposome-mediated MDR1 gene was transferred into bone marrow CD34+ cells. Fluorescence-activated cell sorter was used to evaluate the expression and functional activity of P-glycoprotein (P-gp) encoded by MDR1 gene. It was found that the purity of bone marrow CD34+ cells was approximately (91±4.56) % and recovery rate was (72.3±2.36) % by MACS. The expression of P-gp in the transfected CD34+cells was obviously higher than that in non-transfected CD34+ cells. The amount of P-gp in non-transfected CD34+ cells was (11.2±2.2) %, but increased to (23.6±2.34) % 48 h after gene transfection (P<0.0l). The amount of P-gp was gradually decreased to the basic level one week later. The accumulation and extrusion assays showed that the overexpression of P-gp could efflux Rh-123 out of cells and there was low fluorescence within the transfected cells. The functional activity of P-gp could be inhibited by 10 μg/ml verapamil. It was suggested that the transient and highly effective expression and functional activity of P-gp could be obtained by liposome-mediated MRD1 transferring into human normal bone marrow CD34+ cells. 展开更多
关键词 gene transfection hematopoietic progenitor cell multiple drug resistance gene P-GLYCOPROTEIN
下载PDF
Pathogenic Variation and Occurrence of Multiple Resistance-Breaking <i>Rice yellow mottle virus</i>Strains in Tanzania
9
作者 Judith Hubert Herman J. F. Lyimo Ashura Luzi-Kihupi 《American Journal of Plant Sciences》 2017年第8期1820-1841,共22页
Rice yellow mottle virus (RYMV) is a major biotic constraint for rice production in Africa. The resistance-breaking ability of Tanzanian RYMV strains and phylotypes (S4lm (Tz526), S4lv (Tz516), S4ug (Tz508), S5 (Tz429... Rice yellow mottle virus (RYMV) is a major biotic constraint for rice production in Africa. The resistance-breaking ability of Tanzanian RYMV strains and phylotypes (S4lm (Tz526), S4lv (Tz516), S4ug (Tz508), S5 (Tz429, Tz445), S6c (Tz486) and S6w (Tz539)) were tested by inoculating rice cultivars with RYMV1 resistant alleles (Gigante (rymv1-2), Tog12387 (rymv1-3), Tog5681 (rymv1-3), Tog5438 (rymv1-4), Tog5672 (rymv1-4+rymv2) and Tog5674 (rymv 1-5)) in a screen house. The results revealed multiple resistance-breaking strains and phylotypes on resistant cultivars Gigante, Tog12387, Tog5438 and Tog5681. However, the resistance breakdown was highly variable depending on the strain used, and disease severity ranged from 11% - 75.3%. The virulence potential of RYMV phylotype S4lm (Tz526) was similar to phylotype S6w (Tz539). The impact of strains and phylotypes on yield and its components in rice cultivars revealed highly significant differences (P ≤ 0.001). The lowest percent plant height reduction (2.8%), number of tillers per plant (2.5%), 1000 grain weight (2.7%), spikelet sterility (3.5%) and yield (5%) was recorded in rice cultivar Gigante inoculated with RYMV phylotype S6c (Tz486). Phylotype S6c (Tz486) despite being less virulent compared to other strains, its virus titer in rice cultivar Gigante (1.833) was higher than S5 (Tz429, Tz445) inoculated on Tog5674 (0.171, 0.207) and S6w (Tz539) inoculated on Tog5681 (0.283). The resistant-breaking strain S5 (Tz445) multiplied in resistant rice cultivar Tog5674 without inducing visible symptoms but showed positive reaction to ELISA with low virus titer. The strain S5 overcame wide range of resistant alleles including rymv1-2, rymv1-3, rymv1-4 and rymv1-5 resistance, with exception of rymv1-4 + rymv2. The current results gave a new perspective for future identification of resistance-breaking mutations through sequencing of the RYMV genome in infected rice cultivars and mutagenesis of an infectious viral clone useful for future RYMV resistant breeding programs. 展开更多
关键词 Pathogenic Variation VIRULENCE multiple resistance-Breaking RYMV STRAINS Yield Losses Tanzania
下载PDF
Multiplex PCR Detection of Alleles Responsible for Benzimidazole- Susceptibility or -Resistance in Natural Populations of Haemonchus contortus
10
作者 BOXin-wen LIXiang-rui 《Agricultural Sciences in China》 CAS CSCD 2005年第5期395-400,共6页
A multiplex PCR was developed to detect benzimidazole-resistance (BZ-R) or -susceptibility (BZ-S) in Haemonchus contortus by amplification with 4 primers of a sequence of the GRU-1 gene of β-tubulin of H. contortus m... A multiplex PCR was developed to detect benzimidazole-resistance (BZ-R) or -susceptibility (BZ-S) in Haemonchus contortus by amplification with 4 primers of a sequence of the GRU-1 gene of β-tubulin of H. contortus making use of sequence information available in Genbank. The method was based on two allele-non-specific primers and two allele- specific primers. F1 (264 bp) and F3 (799 bp) should be produced in BZ-R, F2 (585 bp) and F3 in BZ-S. With this method, we demonstrated that H. contortus BZ-R strain from Australia showed F1 and F3, and the worm BZ-S strain from Shanghai did F2 and F3. Sequence analysis of the isotype 1 gene of β-tubulin of BZ-R from Australia and BZ-S from Shanghai showed the code in residue 200 of the gene was respectively TAC and TTC. The LD50 of albendazole of the Australian BZ- R strain was 0.54 μg mL-1, the Shanghai BZ-S strain was only 0.0023 μg mL-1 by EHA (egg hatch assay). The multiplex PCR could determinate the genotype of single adult worm or several third stage larvae and was performed on at least 50 ng of genomic DNA. BZ-R H. contortus were not detected in Shihezi and Yining of the Xinjiang, Wuhe of the Anhui Province, Nanjing and Xuzhou of the Jiangsu Province. The LD50 of the H. contortus from these locations to albendazole as determined by EHA varied between 0.0023-0.0032 μg mL-1. The result indicated that the multiplex PCR could be used to differentiate BZ-R and BZ-S of H. contortus and that the BZ-R situation of H. contortus was not serious in China. 展开更多
关键词 Haemonchus contortus BENZIMIDAZOLE resistance multiplex PCR
下载PDF
A Single-Tube, Functional Marker-Based Multiplex PCR Assay for Simultaneous Detection of Major Bacterial Blight Resistance Genes Xa21, xa13 and xa5 in Rice
11
作者 S.K. Hajira R.M. Sundaram +14 位作者 G.S.Laha A.Yugander S.M.Balachandran B.C.Viraktamath K.Sujatha C.H.Balachiranjeevi K.Pranath M.Amla S.Bhaskar V.Abhilash H.K.Mahadevaswamy M.Kousik T.DilipKumar G.Harika G.Rekha 《Rice science》 SCIE CSCD 2016年第3期144-151,共8页
In marker-assisted breeding for bacterial blight(BB) resistance in rice, three major resistance genes, viz., Xa21, xa13 and xa5, are routinely deployed either singly or in combinations. As efficient and functional mar... In marker-assisted breeding for bacterial blight(BB) resistance in rice, three major resistance genes, viz., Xa21, xa13 and xa5, are routinely deployed either singly or in combinations. As efficient and functional markers are yet to be developed for xa13 and xa5, we have developed simple PCR-based functional markers for both the genes. For xa13, we designed a functional PCR-based marker, xa13-prom targeting the In Del polymorphism in the promoter of candidate gene Os8N3 located on chromosome 8 of rice. With respect to xa5, a multiplex-PCR based functional marker system, named xa5 FM, consisting of two sets of primer pairs targeting the 2-bp functional nucleotide polymorphism in the exon II of the gene TFIIA5(candidate for xa5), has been developed. Both xa13-prom and xa5 FM can differentiate the resistant and susceptible alleles for xa13 and xa5, respectively, in a co-dominant fashion. Using these two functional markers along with the already reported functional PCR-based marker for Xa21(p TA248), we designed a single-tube multiplex PCR based assay for simultaneous detection of all the three major resistance genes and demonstrated the utility of the multiplex marker system in a segregating population. 展开更多
关键词 RICE BACTERIAL blight resistance xa5 xa13 XA21 FUNCTIONAL MARKER multiplex PCR
下载PDF
Multiple drug resistance and bacterial infection
12
作者 Asad U Khan 《Asian Pacific Journal of Tropical Medicine》 SCIE CAS 2008年第4期76-82,共7页
Drug resistance is becoming a great problem in developing countries due to excessive use and misuse of antibiotics. The emergence of new pathogenic strains with resistance developed against most of the antibiotics whi... Drug resistance is becoming a great problem in developing countries due to excessive use and misuse of antibiotics. The emergence of new pathogenic strains with resistance developed against most of the antibiotics which may cause,difficult to treat infection.To understand the current scenario in different mode of infection is most important for the clinicians and medical practitioners.This article summarized some common infections and antibiotic resistance pattern found among these pathogens. 展开更多
关键词 DRUG resistance BACTERIA INFECTION
下载PDF
Plasmid mediated multiple antibiotic resistance in Escherichia coli isolated from community acquired infection of urinary tract in Aligarh Hospital
13
作者 Asad U Khan Saeedut Zafar Ali Mohammed S Zaman 《Asian Pacific Journal of Tropical Medicine》 SCIE CAS 2008年第2期12-15,共4页
This study was to investigate the current trends of multiple drug resistance in bacteria against antibiotics for the proper empirical treatmen.Clinical isolates were collected from community-acquired infection of urin... This study was to investigate the current trends of multiple drug resistance in bacteria against antibiotics for the proper empirical treatmen.Clinical isolates were collected from community-acquired infection of urinary tract patients in Aligarh India from March 1999 to August 1999.Antibiotic susceptibility test was performed,using the disc diffusion method followed by plasmid isolation by the method of Kado and Liu.Transfer experiments were performed by the method of Lederberg and Cohen.Clinical study revealed that this infection was more common in young women.Various strains of E.coli isolated during the course of study were found to show multiple antibiotic resistance which was further characterized as plasmid-borne drug resistance.This study shows that E.coli may be one of the important causative agents of urinary tract infection(UTI) in young women. 展开更多
关键词 PLASMID DRUG resistance UTI
下载PDF
Multiple insecticide resistance/susceptibility status of Culex quinquefasciatus,principal vector of bancroftian filariasis from filaria endemic areas of northern India
14
作者 Kaushal Kumar Abhay K Sharma +3 位作者 Sarita Kumar Sunita Patel Manas Sarkar Chauhan LS 《Asian Pacific Journal of Tropical Medicine》 SCIE CAS 2011年第6期426-429,共4页
Objective:To understand the insecticide resistance status of Culex quinquefasciatus Say(Diptera: Culicidae)(Cx.Quinquefasciatus) to deltamethrin,cyfluthrin,permethrin,lambdacyhalothrin, DDT and malathion in filari... Objective:To understand the insecticide resistance status of Culex quinquefasciatus Say(Diptera: Culicidae)(Cx.Quinquefasciatus) to deltamethrin,cyfluthrin,permethrin,lambdacyhalothrin, DDT and malathion in filarial endemic areas of Uttar Pradesh,India.Methods:Insecticide susceptibility assays were performed on wild-caught adult female Cx.quinquefasciatus mosquitoes to deltamethrin(0.05%),cyfluthrin(0.15%),permethrin(0.75%),lambdacyhalothrin (0.05%),malathion(5.0%) and DDT(4.0%),the discriminating doses recommended by the World Health Organisation(WHO).Results:The data showed that Cx.quinquefasciatus is highly resistant to DDT and malathion;the mortality was 28.33%and 27.5%,respectively and incipient resistance to synthetic pyrethroids(deltamethrin,cyfluthrin,permethrin,and lambdacyhalothrin), where mortality ranged from 95.83%in permethrin to 98.33%in cyfluthrin and lambdacyhalothrin. Knockdown times(KDT<sub>50</sub>) in response to synthetic pyrethroids varied significantly between different insecticides(P【0.01) from 31.480 min for permethrin to 21.650 for cyfluthrin. Conclusions:The results presents here provide the status report of the insecticide resistance/ susceptibility of Cx.quinquefasciatus in major filaria endemic areas of northern India. 展开更多
关键词 INSECTICIDE resistance FILARIA DDT Synthetic PYRETHROID MALATHION CULEX quinquefasciatus
下载PDF
Comparative investigation of the resistance and ability to trigger high voltage discharge for single and multiple femtosecond filaments in air
15
作者 郭凯敏 郝作强 +3 位作者 林景全 孙长凯 高勋 赵振明 《Chinese Physics B》 SCIE EI CAS CSCD 2013年第3期372-374,共3页
A comparative investigation of the resistance and ability to trigger high voltage(HV) discharge for a single filament(SF) and multiple filaments(MFs) has been carried out.The experimental results show that the t... A comparative investigation of the resistance and ability to trigger high voltage(HV) discharge for a single filament(SF) and multiple filaments(MFs) has been carried out.The experimental results show that the trend of the breakdown threshold of the SF exactly follows that of its resistance,but this is not the case for the MF.The MF's resistance is much smaller than the SF's.However,the MF shows a slightly higher HV breakdown threshold than the SF.The underlying physics is that the measured resistance of the MF is collectively contributed by every filament in the MF while the HV breakdown threshold is determined by only one single discharging path. 展开更多
关键词 femtosecond filament resistance high voltage breakdown threshold
下载PDF
Dissemination of Resistance Integrons and Genes Coding for Blse and Cabapenemases in the Urban Drainage Network in Cote d’Ivoire
16
作者 Coulibaly Kalpy Julien Diaby Aboubakar Sidik +8 位作者 Vakou N’dri Sabine M’bengue Gbonon Valérie Carole Claon Jean Stephane Yao Kouamé Eric Gnali Gbohounou Fabrice Yéo Yéfougnini Bagré Issa Djaman Allico Joseph Dosso Mireille 《Advances in Microbiology》 CAS 2024年第5期268-286,共19页
Antibiotic resistance has become a major threat to human health worldwide. Environment, particularly the water environment, has long been overlooked as a player in the antibiotic resistance cycle, although its role re... Antibiotic resistance has become a major threat to human health worldwide. Environment, particularly the water environment, has long been overlooked as a player in the antibiotic resistance cycle, although its role remains unclear. These can provide an ideal setting for the acquisition and dissemination of antibiotic resistance, as they are frequently affected by anthropogenic activities. The objective of this study was to establish a diffusion map of resistance integrons used as genetic markers of resistance associated with antibiotic resistance conferring genes (ARGs). Total DNA extracts from non-cultivable bacterial communities were used for the analyses. These communities were obtained from wastewater samples from 14 sites upstream and downstream of drainage channels or effluents in the cities of Abidjan, Bouaké, and Yamoussoukro. The results obtained correspond to the number of positives among the treated samples (n = 39). Among the genetic markers of dissemination, class 1 integrons were the most evident in 94.8% of samples in Abidjan (93.3%), Bouaké (100%) and Yamoussoukro (91.6%). Class 2 integrons and class 3 integrons were found respectively in 41% and 51% of all samples. Genes coding for β-lactamases and blaTEM was identified in almost all samples at a rate of 97.4%. A co-presence of the three genes blaTEM, blaSHV and blaCTX-M is also remarkable in the sites of the city of Yamoussoukro. Among the genes coding for carbapenemases, only blaKPC 17.94%, blaNDM 30.76% and blaOXA48 38.46% were detected in the samples. 展开更多
关键词 Antibiotic resistance WASTEWATER resistance Integrons (RIs) resistance Genes
下载PDF
Detection of the Mex Efflux Pumps in <i>Pseudomonas</i><i>aeruginosa</i>by Using a Combined Resistance-Phenotypic Markers and Multiplex RT-PCR
17
作者 Kanchana Poonsuk Rungtip Chuanchuen 《Open Journal of Medical Microbiology》 2014年第3期153-160,共8页
The aim of this study was to detect the expression of 4 clinically-important efflux pumps in the Resistance-Nodulation-Cell Division (RND) family including MexAB-OprM, MexXY, MexCD-OprJ and MexEF-OprN in Pseudomonas a... The aim of this study was to detect the expression of 4 clinically-important efflux pumps in the Resistance-Nodulation-Cell Division (RND) family including MexAB-OprM, MexXY, MexCD-OprJ and MexEF-OprN in Pseudomonas aeruginosa using a combination of resistance-phenotypic markers and multiplex RT-PCR (mRT-PCR). The antibiotic substrates specific for each Mex systems were used as phenotypic markers including carbenicillin, MexAB-OprM, erythromycin, MexCD-OprJ, norfloxacin and imipenem, MexEF-OprN and gentamicin, MexXY-OprM. The methods were validated with reference strains with known genotypes of the Mex systems and the potential applicability in clinical practice was tested with clinical isolates. The results for the reference strains support that the combination of resistance phenotype and mRT-PCR is a potential-attractive method for diagnosis of efflux-mediated resistance in P. aeruginosa. Further development to make it more practical for clinical use and study in a larger number of clinical isolates is required. 展开更多
关键词 Multidrug Efflux Pumps multiplex RT-PCR PSEUDOMONAS AERUGINOSA resistance-Phenotypic Marker
下载PDF
Resistance Matrix for an Anisotropic Hall Plate with Multiple Extended Asymmetric Contacts on the Boundary
18
作者 Dorel Homentcovschi Radu Oprea Bruce T. Murray 《Journal of Applied Mathematics and Physics》 2021年第8期1911-1925,共15页
The electrical properties of magnetic sensing devices fabricated from anisotropic materials are not easily extracted. Here we present a method for determining the resistance matrix for an anisotropic device with multi... The electrical properties of magnetic sensing devices fabricated from anisotropic materials are not easily extracted. Here we present a method for determining the resistance matrix for an anisotropic device with multiple electrical contacts placed in a perpendicular magnetic field. By using the methods developed by Van der Pauw and Wasscher, the analysis for the anisotropic system is reduced to the equivalent problem for an isotropic sample, which can then be solved using methods developed previously. As a result, the method works in the case of structures with an arbitrary number of asymmetric extended contacts at large magnetic field strength. In addition to the extraction of nonisotropic resistivities, the resistance matrix can be used to analyze the Hall effect for anisotropic plates. 展开更多
关键词 Hall Device resistance Matrix Van Der Pauw Method ANISOTROPIC
下载PDF
Multiple roles of mothers against decapentaplegic homolog 4 in tumorigenesis, stem cells, drug resistance, and cancer therapy
19
作者 Chuan-Jing Dai Yu-Ting Cao +1 位作者 Fang Huang Yi-Gang Wang 《World Journal of Stem Cells》 SCIE 2022年第1期41-53,共13页
The transforming growth factor(TGF)-βsignaling pathway controls many cellular processes,including proliferation,differentiation,and apoptosis.Abnormalities in the TGF-βsignaling pathway and its components are closel... The transforming growth factor(TGF)-βsignaling pathway controls many cellular processes,including proliferation,differentiation,and apoptosis.Abnormalities in the TGF-βsignaling pathway and its components are closely related to the occurrence of many human diseases,including cancer.Mothers against decapentaplegic homolog 4(Smad4),also known as deleted in pancreatic cancer locus 4,is a typical tumor suppressor candidate gene locating at q21.1 of human chromosome 18 and the common mediator of the TGF-β/Smad and bone morphogenetic protein/Smad signaling pathways.It is believed that Smad4 inactivation correlates with the development of tumors and stem cell fate decisions.Smad4 also interacts with cytokines,miRNAs,and other signaling pathways,jointly regulating cell behavior.However,the regulatory function of Smad4 in tumorigenesis,stem cells,and drug resistance is currently controversial.In addition,Smad4 represents an attractive therapeutic target for cancer.Elucidating the specific role of Smad4 is important for understanding the mechanism of tumorigenesis and cancer treatment.Here,we review the identification and characterization of Smad4,the canonical TGF-β/Smad pathway,as well as the multiple roles of Smad4 in tumorigenesis,stem cells,and drug resistance.Furthermore,we provide novel insights into the prospects of Smad4-targeted cancer therapy and the challenges that it will face in the future. 展开更多
关键词 Cancer therapy Drug resistance Mothers against decapentaplegic homolog 4 STEMNESS Transforming growth factor-β TUMORIGENESIS
下载PDF
Roles of trichomes in tea plant resistance against multiple abiotic and biotic stresses
20
作者 Penghui Li Yanrui Zhang +6 位作者 Zhili Ye Hao Zuo Ping Li Xuecheng Zhao Zhihui Chen Changsong Chen Jian Zhao 《Beverage Plant Research》 2022年第1期103-115,共13页
Tea trichomes contribute significantly to tea flavors by providing diverse and specific flavor-determining metabolites,including catechins,caffeine,theanine,and volatiles.However,not much is known about the physiologi... Tea trichomes contribute significantly to tea flavors by providing diverse and specific flavor-determining metabolites,including catechins,caffeine,theanine,and volatiles.However,not much is known about the physiological functions of tea trichomes in tea plant adaptation to complex environments,nor the trichome development.Tea trichomes not only build up chemical defenses,but also act as the first physical barrier protecting herbivore attacks,reflecting high light and UV-B radiation,and preventing water loss.Moreover,transcriptome profiling on the tea trichomes compared with the trichome-removed leaves also showed that tea trichomes highly expressed numerous defense-related genes involved in protection from high light and UV-B radiation,cold stress,disease resistance signal transduction,anti-herbivore or anti-abiotic peptide biosynthesis,and other defense responses.Several pieces of experimental evidence supported the notes,highlighting the roles of tea trichomes in plant defenses against both abiotic and biotic stresses.The study provides fresh insights into the multiple protective functions of tea trichome for tea plant adaptation to harsh environments.The new understanding on tea trichomes could benefit the development of better breading strategy for new tea varieties with greater adaption and tolerance to changing environmental challenges. 展开更多
关键词 resistance protective removed
下载PDF
上一页 1 2 250 下一页 到第
使用帮助 返回顶部