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Pulmonary cryptococcosis after immunomodulator treatment in patients with Crohn’s disease:Three case reports 被引量:1
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作者 Yan-Fei Fang Xiang-Han Cao +1 位作者 Ling-Ya Yao Qian Cao 《World Journal of Gastroenterology》 SCIE CAS 2023年第4期758-765,共8页
BACKGROUND Corticosteroids and anti-tumor necrosis factorαmAbs are widely used to treat Crohn's disease(CD).However,one disadvantage of this treatment is impairment of normal immune function,leading to an increas... BACKGROUND Corticosteroids and anti-tumor necrosis factorαmAbs are widely used to treat Crohn's disease(CD).However,one disadvantage of this treatment is impairment of normal immune function,leading to an increased risk of infection.Cryptococcus infection is an opportunistic infection that occurs mainly in immunocompromised patients and poses a significant diagnostic challenge in patients with CD.CASE SUMMARY Here,we report three cases of pulmonary cryptococcosis in patients with CD after receiving immunomodulatory treatment.The patients presented with no or mild respiratory symptoms.Chest computed tomography scans revealed pulmonary nodules in the unilateral or bilateral lobes.Diagnoses were made using pathological examination and metagenomic sequencing.The patients were treated with fluconazole 400 mg once daily for 1 to 6 mo,and symptoms were resolved.Literature searches were conducted in PubMed,Web of Science,and Embase to retrieve previously reported cases and summarize patient characteristics.CONCLUSION The incidence of cryptococcus infection has increased along with immunomodulator use.Clinical vigilance is required for early identification and standardized treatment. 展开更多
关键词 Crohn’s disease IMMUNOMODULATOR INFLIXIMAB Opportunistic infections Pulmonary cryptococcosis Case report
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Two-stage reproduction derived from cells of thallus could directly contribute to seeds for green tidal algal Enteromorpha(Ulva) prolifera/clathrata bloom,with disclosure of their ephemeral trait
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作者 Bingxin Huang Lanping Ding +4 位作者 Yao Zhang Youxuan Guo Junxia Liang Yanqi Xie Yue Chu 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2023年第9期101-112,共12页
Green tidal algal Enteromorpha species complete their life cycles by the isomorphic alternation of generations.The provenance of green tide caused by them in the western Yellow Sea has been disputed. The cell reproduc... Green tidal algal Enteromorpha species complete their life cycles by the isomorphic alternation of generations.The provenance of green tide caused by them in the western Yellow Sea has been disputed. The cell reproduction derived from adult thallus was observed on E. clathrata collected from Shantou City, Guangdong Province in this study. Subsequently, it further found that E. proliferia collected from Qingdao City, Shandong Province and Qinhuangdao City, Hebei Province, produced reproductive cells by somatic cells of its early infantile thallus or branch. The latter is functionally similar to that the seedlings of red alga Porphyra yezoensis produce the monospores, and could exquisitely explain the ephemeral or opportunistic trait and environmental adaptation ability of Enteromorpha species. Changes in growth conditions may induce the two types of cell reproduction.They contribute to the bloom, and can effectively reveal the seasonally occurring large-scale and on-year and offyear phenomenon. The latter may have played a decisive role in its formation. This paper analyses the legal status of the species name, the type of generation during bloom, ephemeral traits, the role of microscopic propagule, the area of origin, on-year and off-year phenomenon, early warning and prevention and control of the species, and so on. On this basis, further study on the influence of environmental factors on cell reproduction of early infantile thalli or branches will achieve a positive effect for early warning and prevention and control of the green tidal algal bloom. 展开更多
关键词 green tidal algae Yellow Sea opportunistic trait on-year and off-year early infantile alternation of generations prediction on the occurrence process
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Connected Vehicles Computation Task Offloading Based on Opportunism in Cooperative Edge Computing
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作者 Duan Xue Yan Guo +1 位作者 Ning Li Xiaoxiang Song 《Computers, Materials & Continua》 SCIE EI 2023年第4期609-631,共23页
The traditional multi-access edge computing (MEC) capacity isoverwhelmed by the increasing demand for vehicles, leading to acute degradationin task offloading performance. There is a tremendous number ofresource-rich ... The traditional multi-access edge computing (MEC) capacity isoverwhelmed by the increasing demand for vehicles, leading to acute degradationin task offloading performance. There is a tremendous number ofresource-rich and idle mobile connected vehicles (CVs) in the traffic network,and vehicles are created as opportunistic ad-hoc edge clouds to alleviatethe resource limitation of MEC by providing opportunistic computing services.On this basis, a novel scalable system framework is proposed in thispaper for computation task offloading in opportunistic CV-assisted MEC.In this framework, opportunistic ad-hoc edge cloud and fixed edge cloudcooperate to form a novel hybrid cloud. Meanwhile, offloading decision andresource allocation of the user CVs must be ascertained. Furthermore, thejoint offloading decision and resource allocation problem is described asa Mixed Integer Nonlinear Programming (MINLP) problem, which optimizesthe task response latency of user CVs under various constraints. Theoriginal problem is decomposed into two subproblems. First, the Lagrangedual method is used to acquire the best resource allocation with the fixedoffloading decision. Then, the satisfaction-driven method based on trial anderror (TE) learning is adopted to optimize the offloading decision. Finally, acomprehensive series of experiments are conducted to demonstrate that oursuggested scheme is more effective than other comparison schemes. 展开更多
关键词 Multi-access edge computing opportunistic ad-hoc edge cloud offloading decision resource allocation TE learning
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Pathological and immunohistochemical findings of lungs,heart,liver,and kidneys,and unexpected findings of fungi and parasites in lungs of deceased COVID-19 patients:A case series
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作者 Mehmet N.Yakar Bişar Ergün +10 位作者 Aylin Erol Özde Gökbayrak TekincanÇ.Aktaş Özlem Ulusan Bağcı Fırat Bayraktar Eyüp S.Uçan Begüm Ergan Bilgin Cömert Ayşe Caner Safiye Aktaş Ali N.Gökmen 《Journal of Acute Disease》 2023年第5期204-212,I0001-I0003,共12页
Objective:To define histopathologic and immunohistochemical features of the lungs,heart,liver,and kidneys in patients who died from coronavirus disease 2019(COVID-19),and to determine the presence of SARS-CoV-2 in all... Objective:To define histopathologic and immunohistochemical features of the lungs,heart,liver,and kidneys in patients who died from coronavirus disease 2019(COVID-19),and to determine the presence of SARS-CoV-2 in all tissues,as well as the presence of fungi and parasites in lung tissues.Methods:This retrospective case study was conducted in the intensive care units of Dokuz Eylül University Hospital,and patients(≥18 years)who died due to COVID-19 between October 2020 and April 2021 were included.The biopsy samples of the patient’s lung,heart,liver,and kidney tissues were studied.Results:In the study,we enrolled 12 patients(mean age:70 years;50%male).Alveolar epithelial cell damage and diffuse alveolar damage were predominant in lung tissues.Lobular lymphocyte infiltration,centrilobular sinusoidal dilatation,and microvesicular steatosis in the liver,together with pigmented cast,non-isometric vacuolar degeneration,and capillary plugging in the kidneys,were commonly found among the patients.SARS-CoV-2 nucleocapsid protein antibodies were detected in three lung and two kidney tissues,and so did angiotensin-converting enzyme 2 receptor positivity in one lung and more than half of the kidney tissues.The RT-PCR tests were positive in three lungs and one kidney tissue.After DNA isolation from lung tissues,Pneumocystis jirovecii was detected in nine patients,Aspergillus fumigatus in two,Microsporidia in three,and Cryptosporidium in two.Conclusions:SARS-CoV-2 is a multisystemic disease.Fungi and parasites should be investigated in critically ill COVID-19 patients prescribed corticosteroids. 展开更多
关键词 Biopsy COVID-19 HISTOPATHOLOGY IMMUNOHISTO-CHEMISTRY Opportunistic infections SARS-CoV-2
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Opportunistic Routing with Multi-Channel Cooperative Neighbour Discovery
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作者 S.Sathish Kumar G.Ravi 《Intelligent Automation & Soft Computing》 SCIE 2023年第2期2367-2382,共16页
Due to the scattered nature of the network,data transmission in a dis-tributed Mobile Ad-hoc Network(MANET)consumes more energy resources(ER)than in a centralized network,resulting in a shorter network lifespan(NL).As... Due to the scattered nature of the network,data transmission in a dis-tributed Mobile Ad-hoc Network(MANET)consumes more energy resources(ER)than in a centralized network,resulting in a shorter network lifespan(NL).As a result,we build an Enhanced Opportunistic Routing(EORP)protocol architecture in order to address the issues raised before.This proposed routing protocol goal is to manage the routing cost by employing power,load,and delay to manage the routing energy consumption based on theflooding of control pack-ets from the target node.According to the goal of the proposed protocol techni-que,it is possible to manage the routing cost by applying power,load,and delay.The proposed technique also manage the routing energy consumption based on theflooding of control packets from the destination node in order to reduce the routing cost.Control packet exchange between the target and all the nodes,on the other hand,is capable of having an influence on the overall efficiency of the system.The EORP protocol and the Multi-channel Cooperative Neighbour Discovery(MCCND)protocol have been designed to detect the cooperative adja-cent nodes for each node in the routing route as part of the routing path discovery process,which occurs during control packet transmission.While control packet transmission is taking place during the routing path discovery process,the EORP protocol and the Multi-channel Cooperative Neighbour Discovery(MCCND)protocol have been designed to detect the cooperative adjacent nodes for each node in the routing.Also included is a simulation of these protocols in order to evaluate their performance across a wide range of packet speeds using Constant Bit Rate(CBR).When the packet rate of the CBR is 20 packets per second,the results reveal that the EORP-MCCND is 0.6 s quicker than the state-of-the-art protocols,according to thefindings.Assuming that the CBR packet rate is 20 packets per second,the EORP-MCCND achieves 0.6 s of End 2 End Delay,0.05 s of Routing Overhead Delay,120 s of Network Lifetime,and 20 J of Energy Consumption efficiency,which is much better than that of the state-of-the-art protocols. 展开更多
关键词 Macro-addressable network power-and load-aware routing deterministic and opportunistic routing gradient routing multi-channel cooperative neighbor discovery
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Evolutionary Profile of Opportunistic Infections in People Living with Human Immunodeficiency Virus during Six Months of Dolutegravir Based Antiretroviral Treatment in Kinshasa, Democratic Republic of Congo
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作者 Berry Ikolango Bongenya Marie-Thérèse Ayane Safi Sombo +2 位作者 Benoit Oben Kabengele Guy Makila Mabe Bumoko Erick Ntambwe Kamangu 《World Journal of AIDS》 2023年第2期47-56,共10页
Background: Opportunistic infections (OI), which are still a major problem in the care of People Living with HIV (PLHIV), occur in situations of immunosuppression. The AntiRetroViral Treatments (ART) used allow a spec... Background: Opportunistic infections (OI), which are still a major problem in the care of People Living with HIV (PLHIV), occur in situations of immunosuppression. The AntiRetroViral Treatments (ART) used allow a spectacular reduction in the frequency of Opportunistic Infections. Objective: The objective of this study is to present the evolution of Opportunistic Infections in People Living with HIV under AntiRetroViral Treatment in Kinshasa in the era of Dolutegravir. Methods: The present study is a prospective cohort to present the evolutionary profile of OIs in PLHIV on ART for 6 months in Outpatient Treatment Centers (OTC) in Kinshasa. Sixteen OTCs had been included. The population of the present work was patients over 18 years of age at inclusion, infected with HIV-1 and initiating ART in the selected OTC. Results: On inclusion, 119 patients were included of which 56.3% were women. Malaria (45.4%), tuberculosis (29.4%) and cutaneous pruritus (23.5%) were the most common Opportunistic Infections (OIs). In the third month of ART, 37 patients came for the consultation of which 70.3% were women. Non-specific STIs (97.3%), skin pruritus (37.8%) and malaria (24.3%) were the dominant OIs among patients. At the sixth month of ART, 62 patients came for the medical consultation of which 61.3% were women. Skin pruritus (25.8%), dermatitis (22.6%) and rash (21%) were the most common OIs. Conclusion: The evolutionary profile is marked by the conservation of Opportunistic Infections such as dermatitis (pruritus and rashes) and malaria. 展开更多
关键词 Opportunistic Infections ART Initiation PLHIV KINSHASA
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AVAILABILITY SIMULATION OF MULTI-COMPONENT SYSTEM BASED ON OPPORTUNISTIC MAINTENANCE POLICY 被引量:5
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作者 蔡景 左洪福 吕德峰 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 2009年第3期219-223,共5页
A multi-component system has the long fixed maintenance time, so the opportunistic maintenance policy is adopted to put preventive replacement and corrective replacement together, so that the long fixed maintenance ti... A multi-component system has the long fixed maintenance time, so the opportunistic maintenance policy is adopted to put preventive replacement and corrective replacement together, so that the long fixed maintenance time can be shared by more than one component, and the system availability can be improved. Then, the generation characteristics of the random failure time are researched based on the replacement maintenance and the minima[ maintenance. Furthermore, by choosing the opportunistic replacement ages of each component as opti- mized variables, a simulation algorithm based on an opportunistic maintenance policy is designed to maximize the total availability. Finally, the simulation result shows the validity of the algorithm by an example. 展开更多
关键词 AVAILABILITY multi-component system ALGORITHMS opportunistic maintenance minimal maintenance
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Fungal genus Hypocrea/Trichoderma:from barcodes to biodiversity 被引量:8
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作者 Christian P.KUBICEK Monika KOMON-ZELAZOWSKA Irina S.DRUZHININA 《Journal of Zhejiang University-Science B(Biomedicine & Biotechnology)》 SCIE CAS CSCD 2008年第10期753-763,共11页
Hypocrea/Trichoderma is a genus of soil-borne or wood-decaying fungi containing members important to mankind as producers of industrial enzymes and biocontrol agents against plant pathogens, but also as opportunistic ... Hypocrea/Trichoderma is a genus of soil-borne or wood-decaying fungi containing members important to mankind as producers of industrial enzymes and biocontrol agents against plant pathogens, but also as opportunistic pathogens of immuno- compromised humans and animals, while others can cause damage to cultivated mushroom. With the recent advent of a reliable, BarCode-aided identification system for all known taxa of Trichoderma and Hypocrea, it became now possible to study some of the biological fundamentals of the diversity in this fungal genus in more detail. In this article, we will therefore review recent progress in (1) the understanding of the geographic distribution of individual taxa; (2) mechanisms of speciation leading to development of mushroom diseases and facultative human mycoses; and (3) the possible correlation of specific traits of secondary metabolism and molecular phylogeny. 展开更多
关键词 Hypocrea/Trichoderma Biogeography BIODIVERSITY Facultative human opportunists PEPTAIBOLS Mushroom pathogens
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OE在IPSec中的应用 被引量:1
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作者 李希 刘宏 +1 位作者 姚崎 杨涛 《计算机工程与应用》 CSCD 北大核心 2006年第19期136-139,共4页
OpportunisticEncryption(OE)是基于IPSec协议提出来的一种新的机制。通过OE这种机制使得双方主机在没有预先设置的情况下进行安全的通讯。作为一种标准,只要是使用了OE机制的主机,都可以相互之间任意建立隧道。这就大大增加了建立隧道... OpportunisticEncryption(OE)是基于IPSec协议提出来的一种新的机制。通过OE这种机制使得双方主机在没有预先设置的情况下进行安全的通讯。作为一种标准,只要是使用了OE机制的主机,都可以相互之间任意建立隧道。这就大大增加了建立隧道的灵活性。 展开更多
关键词 OPPORTUNISTIC ENCRYPTION DNS DNSSEC IKE IPSEC
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基于改进MORE协议的无线Mesh网络簇内路由研究 被引量:2
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作者 尹凤杰 关博文 《辽宁大学学报(自然科学版)》 CAS 2022年第1期9-15,共7页
针对视频流传输中延时较大影响用户服务体验问题,本文在无线Mesh网络中以MORE(MAC-independent Opportunistic Routing&Encoding)协议为基础提出一种簇内路由协议,该协议对于MORE协议在传输中源节点和目的节点持续发送重传的问题,... 针对视频流传输中延时较大影响用户服务体验问题,本文在无线Mesh网络中以MORE(MAC-independent Opportunistic Routing&Encoding)协议为基础提出一种簇内路由协议,该协议对于MORE协议在传输中源节点和目的节点持续发送重传的问题,增添了拒绝确认机制,有效地节省了数据包传输过程中的时间,并通过改进MORE协议的编码方式,提出延时最小化网络编码,降低了系统整体的时延水平,保证了系统用户服务体验质量.仿真实验结果表明基于改进MORE协议的簇内路由协议能够有效地降低时延,达到较好的用户服务体验质量. 展开更多
关键词 无线MESH网络 MORE(MAC-independent Opportunistic Routing&Encoding)协议 网络编码 QoE(Quality of Experience)
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Precision screening for esophageal squamous cell carcinoma in China 被引量:18
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作者 Zhonghu He Yang Ke 《Chinese Journal of Cancer Research》 SCIE CAS CSCD 2020年第6期673-682,共10页
Esophageal squamous cell carcinoma(ESCC)is the predominant subtype of esophageal cancer in China,and this neoplasm is associated with high morbidity and mortality as well as clear geographical heterogeneity.Since prim... Esophageal squamous cell carcinoma(ESCC)is the predominant subtype of esophageal cancer in China,and this neoplasm is associated with high morbidity and mortality as well as clear geographical heterogeneity.Since primary prevention for ESCC lacks a clear intervention target,secondary prevention,also known as screening and early diagnosis and early treatment,has become the mainstay of ESCC prevention and control in China.ESCC screening in China has been subject to decades of evaluation and practice.However,the ESCC screening strategy currently adopted in China has encountered a developmental bottleneck.In this review,we have summarized studies and significant findings for ESCC screening and proposed advancement of screening strategies as follows:1)evidence from randomized controlled trials is needed to support the effectiveness and health economic value of endoscopic screening for ESCC;2)the current traditional screening and surveillance strategies warrant reform,and a risk-prediction-based precision strategy should be established;and 3)a deeper understanding of the value of opportunistic screening in the prevention and control of ESCC in China is called for.Due to the low absolute prevalence of precancerous lesions,substantial investment of resources and nonnegligible risks of invasive screening techniques,precision and individualization should be the main direction of cancer screening programs for the future.We advocate cooperation on the part of Chinese scientists to solve this major China-specific health problem in the next decades. 展开更多
关键词 Esophageal cancer organized screening opportunistic screening COST-EFFECTIVENESS risk stratification
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Nested case-control study on risk factors for opportunistic infections in patients with inflammatory bowel disease 被引量:5
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作者 Shan-Shan Gong Yi-Hong Fan +2 位作者 Qing-Qing Han Bin Lv Yi Xu 《World Journal of Gastroenterology》 SCIE CAS 2019年第18期2240-2250,共11页
BACKGROUND When opportunistic infections occur, patients with inflammatory bowel disease(IBD) commonly display a significantly increased rate of morbidity and mortality.With increasing use of immunosuppressive agents ... BACKGROUND When opportunistic infections occur, patients with inflammatory bowel disease(IBD) commonly display a significantly increased rate of morbidity and mortality.With increasing use of immunosuppressive agents and biological agents,opportunistic infections are becoming a hot topic in the perspective of drug safety in IBD patients. Despite the well-established role of opportunistic infections in the prognosis of IBD patients, there are few epidemiological data investigating the incidence of opportunis-tic infections in IBD patients in China. Besides, the risk factors for opportunistic infection in Chinese IBD patients remain unclear.AIM To predict the incidence of opportunistic infections related to IBD in China, and explore the risk factors for opportunistic infections.METHODS A single-center, prospective study of IBD patients was conducted. The patients were followed for up to 12 mo to calculate the incidence of infections. For each infected IBD patient, two non-infected IBD patients were selected as controls. A conditional logistic regression analysis was used to assess associations between putative risk factors and opportunistic infections, which are represented as odds ratios(OR) and 95% confidence intervals(CIs).RESULTS Seventy(28.11%) out of 249 IBD patients developed opportunistic infections.Clostridium difficile infections and respiratory syncytial virus infections were found in 24 and 16 patients, respectively. In a univariate analysis, factors such as the severity of IBD, use of an immunosuppressant or immunosuppressants, high levels of fecal calprotectin, and C-reactive protein or erythrocyte sedimentation rate were individually related to a significantly increased risk of opportunistic infection. Multivariate analysis indicated that the use of any immunosuppressant yielded an OR of 3.247(95%CI: 1.128-9.341), whereas the use of any two immunosuppressants yielded an OR of 6.457(95%CI: 1.726-24.152) for opportunistic infection. Interestingly, when immunosuppressants were used in combination with infliximab(IFX) or 5-aminosalicylic acid, a significantly increased risk of opportunistic infection was also observed. The relative risk of opportunistic infection was greatest in IBD patients with severe disease activity(OR = 9.090; 95%CI: 1.532-53.941, relative to the remission stage). However, the use of IFX alone did not increase the risk of opportunistic infection.CONCLUSION Factors such as severe IBD, elevated levels of fecal calprotectin, and the use of immunosuppressive medications, especially when used in combination, are major risk factors for opportunistic infections in IBD patients. The use of IFX alone does not increase the risk of opportunistic infection. 展开更多
关键词 Nested CASE-CONTROL study OPPORTUNISTIC INFECTIONS INFLAMMATORY BOWEL disease
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Opportunistic and other intestinal parasites among HIV/AIDS patients attending Gambi higher clinic in Bahir Dar city,North West Ethiopia 被引量:5
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作者 Abebe Alemu Yitayal Shiferaw +2 位作者 Gebeyaw Getnet Aregaw Yalew Zelalem Addis 《Asian Pacific Journal of Tropical Medicine》 SCIE CAS 2011年第8期661-665,共5页
Objective:To determine the magnitude of opportunistic and non-opportunistic intestinal parasitic infections among HTV/AIDS patients in Bahir Dar.Methods:Cross-sectional study was conducted among HIV/ AIDS patients att... Objective:To determine the magnitude of opportunistic and non-opportunistic intestinal parasitic infections among HTV/AIDS patients in Bahir Dar.Methods:Cross-sectional study was conducted among HIV/ AIDS patients attending Gambi higher clinic from Aprill- May 30,2009. Convenient sampling technique was employed to identify the study subjects and hence a total of 248 subjects were included.A pre-tested structured questionnaire was used to collect sociodemographic data of patients.Stool samples were examined by direct saline,iodine wet mount, formol-ether sedimentation concentration and modified Ziehl-Neelsen staining technique. Results:Out of 248 enrolled in the study,171(69.0%)(90 males and 81 females) were infected with one or more intestinal parasites.The highest rate of intestinal parasites were observed among HIV/AIDS patients(80.3%,151/188),and the infection rate of HIV negative individuals was 33.3%(20/60).Cryptosporidum parvum(43.6%),Isospora belli(15.5%) and Blastocystis hominis (10.5%) were opportunistic parasites that were found only in HIV/AIDS patients.Conclusions: Opportunistic parasite infections are common health problem among HIV/ AIDS patients in the study area.Therefore,early detection and treatment of these parasites are important to improve the quality of life of HIV/AIDS patients. 展开更多
关键词 OPPORTUNISTIC parasites Non-opportunistic parasites HIV/AIDS Ethiopia
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Effectiveness of gastric cancer screening programs in South Korea:Organized vs opportunistic models 被引量:5
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作者 Beom Jin Kim Chae Heo +2 位作者 Byoung Kwon Kim Jae Yeol Kim Jae Gyu Kim 《World Journal of Gastroenterology》 SCIE CAS 2013年第5期736-741,共6页
AIM:To investigate the outcome and effectiveness of two screening programs,National Cancer Screening Program(NCSP)and opportunistic screening(OS),for the detection of gastric cancer. METHODS:A total of 45 654 subjects... AIM:To investigate the outcome and effectiveness of two screening programs,National Cancer Screening Program(NCSP)and opportunistic screening(OS),for the detection of gastric cancer. METHODS:A total of 45 654 subjects underwent upper endoscopy as part of the NCSP or OS at the Chung-Ang University Healthcare System in Korea between January 2007 and December 2010.The study population was comprised of subjects over the age of 40 years.More specifically,subjects who took part in the NCSP were Medicaid recipients and beneficiaries of the National Health Insurance Corporation.Still photo-graphs from the endoscopies diagnosed as gastric cancer were reviewed by two experienced endoscopists. RESULTS:The mean age of the screened subjects was 55 years for men and 54 years for women.A total of 126 cases(0.28%)of gastric cancer were detected from both screening programs;100 cases(0.3%)from NCSP and in 26 cases(0.2%)from OS.The proportion of early gastric cancer(EGC)detected in NCSP was higher than that in OS(74.0%vs 53.8%,P=0.046). Among the 34 416 screenees in NCSP,6585(19.1%) underwent upper endoscopy every other year as scheduled.Among the 11 238 screenees in OS,3050(27.1%) underwent upper endoscopy at least once every two years during the study period.The detection rate of gastric cancer was found to be significantly higher during irregular follow-up than during regular follow-up in both screening programs(0.3%vs 0.2%,P=0.036).A higher incidence of EGC than advanced gastric cancer was observed during regular follow-up compared with irregular follow-up. CONCLUSION:Compliance to the screening program is more important than the type of screening system used. 展开更多
关键词 GASTRIC CANCER National CANCER SCREENING Program OPPORTUNISTIC SCREENING Early GASTRIC CANCER
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Polyphase orthogonal sequences design for opportunistic array radar via HGA 被引量:9
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作者 Shufeng Gong Weijun Long +2 位作者 Hao Huang De Ben Minghai Pan 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2013年第1期60-67,共8页
Opportunistic array radar (OAR) is a new generation radar system based on the stealth of the platform, which can improve the modern radar performance effectively. Designing the orthogonal code sets with low autocorr... Opportunistic array radar (OAR) is a new generation radar system based on the stealth of the platform, which can improve the modern radar performance effectively. Designing the orthogonal code sets with low autocorrelation and cross-correlation is a key issue for OAR. This paper proposes a novel hybrid genetic algorithm (HGA) and designs the polyphase orthogonal code sets with low autocorrelation and cross-correlation properties, which can be used in the OAR system. The novel algorithm combines with simulated annealing (SA) and genetic algorithm (GA), adds in keeping best individuals and competition in small scope, and introduces grey correlation evaluation to evaluate fitness function. These avoid the premature convergence problem existed in GA and enhance the global searching capability. At last, the genetic results are optimized to obtain the best solution by using greedy algorithm. The simulation results show that the proposed algorithm is effective for the design of orthogonal phase signals used in OAR systems. 展开更多
关键词 hybrid genetic algorithm (HGA) grey correlation evaluation opportunistic array radar (OAR) orthogonal signal.
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A Utility-Based Buffer Management Policy for Improving Data Dissemination in Opportunistic Networks 被引量:5
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作者 Jiansheng Yao Chunguang Ma +2 位作者 Haitao Yu Yanling Liu Qi Yuan 《China Communications》 SCIE CSCD 2017年第7期118-126,共9页
In opportunistic networks, most existing buffer management policies including scheduling and passive dropping policies are mainly for routing protocols. In this paper, we proposed a Utility-based Buffer Management str... In opportunistic networks, most existing buffer management policies including scheduling and passive dropping policies are mainly for routing protocols. In this paper, we proposed a Utility-based Buffer Management strategy(UBM) for data dissemination in opportunistic networks. In UBM, we first design a method of computing the utility values of caching messages according to the interest of nodes and the delivery probability of messages, and then propose an overall buffer management policy based on the utility. UBM driven by receivers completely implements not only caching policies, passive and proactive dropping policies, but also scheduling policies of senders. Simulation results show that, compared with some classical dropping strategies, UBM can obtain higher delivery ratio and lower delay latency by using smaller network cost. 展开更多
关键词 opportunistic networks data dissemination buffer management strategy utility-based
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Opportunistic maintenance for multi-component systems considering structural dependence and economic dependence 被引量:6
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作者 Junbao Geng Michael Azarian Michael Pecht 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2015年第3期493-501,共9页
Although opportunistic maintenance strategies are widely used for multi-component systems, all opportunistic mainte- nance strategies only consider economic dependence and do not take structural dependence into accoun... Although opportunistic maintenance strategies are widely used for multi-component systems, all opportunistic mainte- nance strategies only consider economic dependence and do not take structural dependence into account. An opportunistic main- tenance strategy is presented for a multi-component system that considers both structural dependence and economic dependence. The cost relation and time relation among components based on structural dependence are developed. The maintenance strategy for each component of a multi-component system involves one of five maintenance actions, namely, no-maintenance, a minimal maintenance action, an imperfect maintenance action, a perfect maintenance action, and a replacement action. The maintenance action is determined by the virtual age of the component, the life expectancy of the component, and the age threshold values. Monte Carlo simulation is designed to obtain the optimal oppor- tunistic maintenance strategy of the system over its lifetime. The simulation result reveals that the minimum maintenance cost with a strategy that considers structural dependence is less than that with a strategy that does not consider structural dependence. The availability with a strategy that considers structural dependence is greater than that with a strategy that does not consider structural dependence under the same conditions. 展开更多
关键词 opportunistic maintenance multi-component system structural dependence Monte Carlo simulation maintenance cost.
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Microbiological assessment of indoor air of a teaching hospital in Nigeria 被引量:7
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作者 Awosika SA Olajubu FA Amusa NA 《Asian Pacific Journal of Tropical Biomedicine》 SCIE CAS 2012年第6期465-468,共4页
Objective:To investigate the quality of indoor air of different wards and units of Olabisi Onabanjo University Teaching Hospital, Sagamu, to ascertain their contribution to infection rate in the hospital.Methods:The m... Objective:To investigate the quality of indoor air of different wards and units of Olabisi Onabanjo University Teaching Hospital, Sagamu, to ascertain their contribution to infection rate in the hospital.Methods:The microbial quality of indoor air of nine wards/units of Olabisi Onabanjo University Teaching Hospital, Sagamu, Nigeria was conducted. Sedimentation technique using open Petri-dishes containing different culture media was employed and samplings were done twice daily, one in the morning shortly after cleaning and before influx of people/patients into the wards/units and the other in the evening when a lot of activities would have taken place in these wards. Isolates were identified according to standard methods.Results:Results showed that there was a statistically significant difference(氈2= 6.0167) in the bacteria population of the different sampling time whereas it was not so for fungi population(氈2= 0.2857). Male medical ward(MMW) and male surgical general(MSG) recorded the highest bacterial and fungal growth while the operating theatre(OT) was almost free of microbial burden. The bacteria isolates were Staphylococcus aureus, Klebsiellasp., Bacillus cereus, Bacillus subtilis, Streptococcus pyogenes andSerratia marscenceswhile the fungi isolates includedAspergillus flavus, Penicilliumsp.,Fusariumsp.,Candida albicansandAlternariasp.Staphylococcus aureuswas the predominantly isolated bacterium whilePenicilliumsp. was the most isolated fungus.Conclusions:Though most of the microbial isolates were potential and or opportunistic pathogens, there was no correlation between the isolates in this study and the surveillance report of nosocomial infection during the period of study, hence the contribution of the indoor air cannot be established. From the reduction noticed in the morning samples, stringent measures such as proper disinfection and regular cleaning, restriction of patient relatives' movement in and out of the wards/units need to be enforced so as to improve the quality of indoor air of our hospital wards/units. 展开更多
关键词 Indoor air OOUTH Open-plate TECHNIQUE NOSOCOMIAL infections STAPHYLOCOCCUS aureus Microbiological assessment MICROBIAL quality Bacterial ISOLATE Fungal ISOLATE Opportunistic pathogen NOSOCOMIAL INFECTION INFECTION rate MICROBIAL ISOLATE Penicilliumsp Sedimentation TECHNIQUE
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Data Distribution Mechanism over Opportunistic Networks with Limited Epidemic 被引量:5
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作者 GUO Da CHENG Gang +2 位作者 ZHANG Yong SONG Mei Amanda Matthews 《China Communications》 SCIE CSCD 2015年第6期154-163,共10页
Most of data distribution mechanism in Opportunistic Networks is derived by Epidemic data distribution,and Epidemic data distribution means that when each node meets another node,it may copy its own messages and trans... Most of data distribution mechanism in Opportunistic Networks is derived by Epidemic data distribution,and Epidemic data distribution means that when each node meets another node,it may copy its own messages and transfer to another node.On the one hand,the copies improve the forwarding rate,and reduce the transmission delay.However,on the other hand,energy consumption increases and network survival time is reduced because the copies consume transmission resource.Therefore,copy number should be under control.In this paper,we first introduce the existing routing strategy based on Epidemic briefly,and present the Epidemic routing protocol analysis model and copy control mechanism based on the limited Epidemic in Opportunistic Networks.Then based on the limited copies scheme(LCS),we propose an energy balance scheme(EBS),the results show that EBS can improve the network survival time. 展开更多
关键词 opportunistic networks delay tol-erant networks Markov chain
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Role of upper endoscopy in diagnosing opportunistic infections in human immunodeficiency virus-infected patients 被引量:4
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作者 Ana Luiza Werneck-Silva Ivete Bedin Prado 《World Journal of Gastroenterology》 SCIE CAS CSCD 2009年第9期1050-1056,共7页
Highly active antiretroviral therapy (HAART) has dramatically decreased opportunistic infections (OIs) in human immunodef iciency virus (HIV)-infected patients. However,gastrointestinal disease continues to account fo... Highly active antiretroviral therapy (HAART) has dramatically decreased opportunistic infections (OIs) in human immunodef iciency virus (HIV)-infected patients. However,gastrointestinal disease continues to account for a high proportion of presenting symptoms in these patients. Gastrointestinal symptoms in treated patients who respond to therapy are more likely to the result of drug-induced complications than OI. Endoscopic evaluation of the gastrointestinal tract remains a cornerstone of diagnosis,especially in patients with advanced immunodeficiency,who are at risk for OI. The peripheral blood CD4 lymphocyte count helps to predict the risk of an OI,with the highest risk seen in HIV-infected patients with low CD4 count (< 200 cells/mm3). This review provides an update of the role of endoscopy in diagnosing OI in the upper gastrointestinal tract in HIV-infected patients in the era of HAART. 展开更多
关键词 Human immunodeficiency virus Opportunistic infections Upper gastrointestinal tract Gastrointestinal endoscopy Highly active antiretroviral therapy
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