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Seasonal changes in sperm parameters, testicular histology and circulating levels of reproductive hormones in the male African straw-colored fruit bat (Eidolon helvum)

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Asian pacific Journal of Reproduction 2020年第4期9卷 197-203页

作者： clifford n abiaezute Chike F Oguejiofor Innocent C nwaogu Ikechukwu R Obidike Udensi M Igwebuike Department of Veterinary Anatomy Faculty of Veterinary MedicineUniversity of NigeriaNsukka 410001Nigeria Department of Veterinary Obstetrics and Reproductive Diseases Faculty of Veterinary MedicineUniversity of NigeriaNsukka 410001Nigeria Department of Veterinary Physiology and Pharmacology Faculty of Veterinary MedicineUniversity of NigeriaNsukka 410001Nigeria

Objective: To investigate seasonal changes in some reproductive characteristics of the male African straw-colored fruit bat [Eidolon (E.) helvum] in a tropical rain forest area of South-East ***: Spermatozoal characteristics in the testes and cauda epididymides, testicular histology, and the circulating levels of the reproductive hormones, testosterone, follicle stimulating hormone and luteinizing hormone were evaluated in male bats captured in late January (peak dry season), late May (early rainy season) and late September (late rainy season) of 2019. The bats were captured in Obiagu community in Enugu State, South-East nigeria. Data were analyzed with analysis of variance. Results: There were high serum concentrations of testosterone in early and late rainy season and of luteinizing hormone in early rainy season, but the concentrations of both hormones were low during peak dry season. These hormonal changes corresponded with the testicular seminiferous and spermatogenic activities and testicular and epididymal sperm concentrations, which were also maximal during early and late rainy season but minimal during peak dry season. Epididymal sperm motility and vitality were also high in early and late rainy season but low in peak dry season, while sperm morphological abnormalities were low in early and late rainy season but elevated in peak dry season. There was histological evidence that spermatogenesis did not cease completely during testis regression, but continued at a reduced rate during the dry season. Conclusions: The findings do not support concurrent epididymal sperm storage with testis regression in E. helvum. Altogether, these indicate that seasonal changes significantly alter sperm characteristics, testicular histology and circulating levels of reproductive hormones in E. helvum within the study area.

关键词： Eidolon helvum Spermatozoa Reproductive characteristics Seasonal changes

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Geochemical fingerprints and hydrocarbon potential of Paleocene mudrocks in the Tano Basin, Ghana: insights from biomarkers and stable carbon isotopes

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Acta Geochimica 2024年第2期43卷 255-279页

作者： Kojo Amoako nancy Pearl Osei-Boakye ningning Zhong n’Guessan Francois De Sales Konan Gordon Foli Prince Opoku Appau clifford Fenyi Ebenezer Apesegah Research Group for Marine Geochemistry(ICBM-MPI Bridging Group) Institute for Chemistry and Biology of the Marine Environment(ICBM)Carl von Ossietzky University OldenburgAmmerlander Heerstr.26129 OldenburgGermany State Key Laboratory of Petroleum Resources and Prospecting College of GeosciencesChina University of PetroleumBeijing 102249China Department of Geological Engineering Faculty of Civil and Geo-EngineeringKwame Nkrumah University of Science and TechnologyKumasiGhana Ghana national Gas Company 225 Osibisa CloseAirport WestAccraGhana Petroleum Corporation GNPCPMBPetroleum HouseTemaGhana

The Paleocene mudrocks in Ghana’s Tano Basin have received limited attention despite ongoing efforts to explore hydrocarbon resources.A thorough geochemical analysis is imperative to assess these mudrocks’petroleum generation potential and formulate effective exploration *** this study,a comprehensive geochemical analysis was carried out on ten Paleocene rock cuttings extracted from TP-1,a discovery well within the Tano *** analytical techniques,including total organic carbon(TOC)analysis,Rock–Eval pyrolysis,gas chromatography-mass spectrometry,and isotope ratio-mass spectrometry,were employed to elucidate their hydrocar-bon potential and organic ***ﬁndings in this study were subsequently compared to existing geochemical data on Paleocene source rocks in the South Atlantic marginal *** results indicated that the Paleocene samples have TOC content ranging from 0.68 to 2.93 wt%.The prevalent kerogen types identiﬁed in these samples were Type Ⅱ and Type Ⅲ.Molecular and isotope data suggest that the organic matter found in the Paleocene mudrocks can be traced back to land plants and lower aquatic *** mudrocks were deposited in a transi-tional environment withﬂuctuating water salinity,charac-terized by sub-oxic redox *** indices,both bulk and molecular,indicated a spectrum of maturity levels within the Paleocene mudrocks,spanning from immature to marginally mature,with increasing maturity observed with greater *** comparison,the organic composition and depositional environments of Paleocene source rocks in the Tano Basin closely resemble those found in the niger Delta Basin,Douala,and Kribi-Campo Basins,the Kwanza Formation in Angola,and certain Brazilian marginal ***,it is worth noting that Paleocene source rocks in some of the basins,such as the niger Delta and Brazilian marginal basins,exhibit rela-tively higher thermal maturity levels compared to those observed in the current Paleocene samp

关键词： Paleocene source rocks Source input Depositional environment Thermal maturity Hydrocarbon potential Tano Basin West Africa

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nurses’perceptions about neonatal intensive care units providing family-centered care are associated with skin-to-skin contact implementation

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Pediatric Investigation 2024年第1期8卷 61-65页

作者： Marilyn Aita Gwenaëlle De clifford-Faugère Geneviève Laporte Sébastien Colson nancy Feeley Faculty of nursing Universitéde MontréalMontrealCanada CHU Sainte-Justine Research Centre MontrealCanada Quebec network on nursing Intervention Research MontrealCanada Faculty of Medical and Paramedical Sciences CEReSSAix-Marseille UniversitéMarseilleFrance Ingram School of nursing McGill UniversityMontrealCanada Centre for nursing Research and Lady Davis Institute Jewish General HospitalMontrealCanada

Skin-to-skin contact(SSC)consists of positioning the diaper-clad infant against the parent’s chest and is considered a nursing practice rooted in family-centered care(FCC).1 SSC implies simultaneous parental presence and helps to facilitate their involvement from the earliest hours of their preterm infants’lives as this intervention is delivered by parents.1 FCC has gained worldwide popularity in recent years to promote parental presence and active participation of parents in care during neonatal intensive care units(nICUs)hospitalization.2 Both practices relate to developmental care(DC),which regroups specific interventions aimed at reducing stress and improving infant neurological development.

关键词： centered gained Skin

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Osteocyte viability and bone density in cadmium chloride-induced osteoporosis ameliorated with Pilostigma thonningii stem bark-extracted D-3-O-methy-chiroinositol

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Animal Models and Experimental Medicine 2019年第1期2卷 25-33页

作者： Edwin Aihanuwa Uwagie-Ero clifford nwabugwu abiaezute Chinaka O.nwaehujor Theophilus Okafor nnaji Eugene Amienwanlen Odigie Oyetunde Kazeem Ekeolu Ohiemi Benjamin Ocheja Department of Surgery Faculty of Veterinary MedicineUniversity of Benin Department of Anatomy Faculty of Veterinary MedicineUniversity of Nigeria Department of Biochemistry College of Basic Medical SciencesUniversity of Calabar Department of Surgery Faculty of Veterinary MedicineUniversity of Nigeria Department of Anatomy Faculty of Veterinary MedicineUniversity of Benin Department of Physiology and Biochemistry Faculty of Veterinary MedicineUniversity of Benin

Background : This study examined the ameliorative effect of D-3-O-methylchiroinositol, isolated from the stem bark of Piliostigma thonningii, on cadmium chloride-induced osteoporosis in male Wistar rats. Methods : Thirty-six rats were assigned to three treatment groups(n = 12). Group A(2 mL distilled water), group B:(2.5 mg/kg b.w. CdCl_2) and group C:(2.5 mg/kg b.w. CdCl_2 and D-3-O-methyl-chiroinositol 2 mg/kg b.w.). Bone ash, calcium, phosphate, magnesium, and zinc content, as well as bone histological changes were determined at the end of months 1, 2, and 3. Results : There were significant differences( P ≤ 0.05) in the weight of the cervical, tibia, and femoral bones in all groups. The serum concentration of CdCl_2 was significantly different across the three groups with time. There was significant variation( P n the mean bone ash across groups. The concentration of OH-proline was significantly different( P nificant differences( P n bone calcium, magnesium, zinc, and phosphorus concentrations. Histology revealed high levels of bone mineralisation in the CdCl_2-treated group, indicative of osteoporosis with hypertrophied osteocytes, while the femur of Wistar rats treated with D-3-O-methyl-chiroinositol showed bone trabeculae and viable osteocytes. Conclusion : The study concluded that D-3-O-methyl-chiroinositol extract from Piliostigma thionningii stem bark ameliorated cadmium chloride-induced osteoporosis in male Wistar rats.

关键词： cadmium chloride D-3-O-methyl-chiroinositol osteocytes osteoporosis toxicity amelioration

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Quality vs. quantity of publications in nanotechnology field from the People’s Republic of China

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Chinese Science Bulletin 2008年第8期53卷 1272-1280页

作者： Ronald n. KOSTOFF Ryan B. BARTH clifford G. Y. LAU Office of naval Research 875 N. Randolph St. Arlington 22217 VA USA DDL-OMnI Engineering LLC 8260 Greensboro Drive Suite 600 McLean VA USA Institute for Defense Analyses 4850 Mark Center Drive Alexandria VA USA

This study evaluates trends in quality of nanotechnology and nanoscience papers produced by au- thors from the People’s Republic of China (PRC). The metric used to gauge quality is ratio of highly cited nanotechnology papers to total nanotechnology papers produced in sequential time frames. The USA is both the most prolific nanotechnology publishing country and most represented country on highly cited nanotechnology papers (both in absolute numbers of highly cited papers and highly cited papers relative to total publications) over the 1998―2003 time frame, based on the SCI/SSCI databases. Some of the smaller hi-tech countries have relatively high ratios (~2) of highly cited papers to total publications (e.g. Denmark, netherlands, Switzerland). Countries that have exhibited rapid growth in SCI/SSCI nanotechnology paper production in recent years (e.g. PRC, South Korea) had ratios an order of magnitude less than that of the USA for 1998, but by 2003 had increased to about 20% that of the USA (~2.5). PRC and South Korea have climbed in the publications rankings from 6th and 9th in 1998, re- spectively, to 2nd and 6th in 2005, respectively. PRC’s ratio monotonically increased from 0.16 to 0.45 over the 1998―2003 period, and South Korea’s ratio increased from 0.11 to about 0.6 over that same period, indicating their papers are getting more and more citations proportionately. Thus, under rapid growth conditions, PRC and South Korea have been able to increase their share of participation in highly cited papers. As of 2003, PRC and South Korea have ratios comparable to nations like Japan, France, Italy, and Australia but not yet approaching those of the highly cited countries. none of the top ten publications producing institutions are from the USA, while all of the top ten highly cited publica- tions producers are from the USA. Over the 1998―2003 time period, the top six total publications pro- ducing institutions (globally) remained the same, with Chinese Academy of Scien

关键词：纳米技术纳米科学引用分析中国

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LC-MS^n比较分析三种传统中草药中绿原酸及其衍生物组分(英文)

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药学学报 2008年第2期43卷 185-190页

作者：王征 clifford Michael n 湖南农业大学生物科学技术学院湖南长沙410128 英国萨里大学生物医学与分子科学学院食品营养与安全研究中心吉尔福德萨里郡GU2 7XH

利用LC-MSn分析了杜仲叶、金银花叶以及鱼腥草叶甲醇提取物中绿原酸及其异构体和衍生物。发现3种样品中都含有3种单咖啡酰奎尼酸(绿原酸),分别是3-咖啡酰奎尼酸(3-caffeoylquinic acid,3-CQA)、4-CQA和5-CQA。杜仲叶和金银花叶中5-CQA... 详细信息

利用LC-MSn分析了杜仲叶、金银花叶以及鱼腥草叶甲醇提取物中绿原酸及其异构体和衍生物。发现3种样品中都含有3种单咖啡酰奎尼酸(绿原酸),分别是3-咖啡酰奎尼酸(3-caffeoylquinic acid,3-CQA)、4-CQA和5-CQA。杜仲叶和金银花叶中5-CQA为主要成分,但鱼腥草叶中以3-CQA和4-CQA为主要成分。在杜仲叶中首次发现咖啡酰奎尼酸糖苷;另外还发现金银花叶中有少量5-阿魏酰奎尼酸(5-feruloylquinic acid,5-FQA);鱼腥草叶含有少量的3-FQA和4-肉桂酰奎尼酸(4-p-coumaroylquinic acid,4-pCoQA)。本文首次报道鱼腥草叶中绿原酸异构体成分,为3-CQA和4-CQA的开发提供了来源(植物中绿原酸的结构一般以5-CQA为主)。

关键词：杜仲金银花鱼腥草 LC-MS^n 咖啡酰奎尼酸阿魏酰奎尼酸肉桂酰奎尼酸咖啡酰奎尼酸糖苷

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Fever of unknown origin:a retrospective review of pediatric patients from an urban,tertiary care center in Washington,DC

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World Journal of Pediatrics 2020年第2期16卷 177-184页

作者： Ann Marie Szymanski Hugo clifford Tova Ronis Division of Pediatric Rheumatology Children's National Health SystemWashingtonDCUSA national Institute of Arthritis and Musculoskeletal and Skin Diseases National Institutes of HealthBuilding 10Rm 12S251 MSC 156010 Center DriveBethesdaMD 20814USA The School of Medicine and Health Sciences The George Washington UniversityWashingtonDCUSA

Background Fever of unknown origin(FUO)continues to challenge clinicians to determine an etiology and the need for *** study explored the most common etiologies,characteristics,and average cost of hospitalization for FUO in a pediatric population at an urban,tertiary care hospital in Washington,*** Records from patients admitted to Children's national Health System between September 2008 and April 2014 with an admission ICD-9 code for fever(780.6)were *** charts of patients 2-18 years of age with no underlying diagnosis and a temperature greater than 38.3℃for 7 days or more at time of hospitalization were *** diagnoses,features of admission,and total hospital charges were *** 110 patients qualified for this *** majority of patients(n=42,38.2%)were discharged without a *** was followed closely by infection,accounting for 37.2%(n=41)of *** disease was next(n=16,14.5%),followed by miscellaneous(n=6,5.4%)and oncologic diagnoses(n=5,4.5%).The average cost of hospitalization was 40,295 US *** This study aligns with some of the most recent publications which report undiagnosed cases as the most common outcome in patients hospitalized with *** that,often no diagnosis is found may reassure patients,families,and *** cost associated with hospitalization for FUO may cause clinicians to reconsider inpatient admission for diagnostic work-up of fever,particularly given the evidence demonstrating that many patients are discharged without a diagnosis.

关键词： Fever Fever of unknown origin Infection Healthcare costs

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Gene expression profiling of MYC-driven tumor signatures in porcine liver stem cells by transcriptome sequencing

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World Journal of Gastroenterology 2015年第7期21卷 2011-2029页

作者： Rajagopal n Aravalli neil C Talbot clifford J Steer Department of Radiology University of Minnesota Medical School Minneapolis Beltsville Agricultural Research Center US Department of Agriculture Departments of Medicine and Genetics Cell Biology and Development University of Minnesota

AIM:To identify the genes induced and regulated by the MYC protein in generating tumors from liver stem ***:In this study,we have used an immortal porcine liver stem cell line,PICM-19,to study the role of c-MYC in ***-19 cells were converted into cancer cells(PICM-19-CSCs)by overexpressing human *** identify MYC-driven differential gene expression,transcriptome sequencing was carried out by RnA sequencing,and genes identified by this method were validated using real-time *** vivo tumorigenicity studies were then conducted by injecting PICM-19-CSCs into the flanks of immunodeficient ***:Our results showed that MYC-overexpressing PICM-19 stem cells formed tumors in immunodeficient mice demonstrating that a single oncogene was sufficient to convert them into cancer cells(PICM-19-CSCs).By using comparative bioinformatics analyses,we have determined that>1000 genes were differentially expressed between PICM-19 and *** ontology analysis further showed that the MYCinduced,altered gene expression was primarily associated with various cellular processes,such as metabolism,cell adhesion,growth and proliferation,cell cycle,inflammation and ***,six genes expressed by PICM-19 cells(CDO1,C22orf39,DKK2,EnPEP,GPX6,SRPX2)were completely silenced after MYC-induction in PICM-19-CSCs,suggesting that the absence of these genes may be critical for ***:MYC-driven genes may serve as promising candidates for the development of hepatocellular carcinoma therapeutics that would not have deleterious effects on other cell types in the liver.

关键词： Hepatocellular carcinoma MYC Stem cells Gene expre

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Fusing Conventional ECG QRS Detection Algorithms with an Auto-associative neural network for the Detection of Ectopic Beats

Fusing Conventional ECG QRS Detection Algorithms with an Aut...

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2000年第16届世界计算机大会

作者： G.clifford L.Tarassenko n.Townsend Department of Engineering Science University of Oxford Parks RoadOxfordOX1 3PJUK

＜正＞The onset of a potentially fatal arrhythmia is often preceded by abnormal morphologies in the QRS complex, the main feature in the ***, these ectopic beats are difficult to detect as their shape is very similar to those found in a normal sinus *** show how an auto-associative multi-layer perceptron can be trained to detect normal beats only, so that the subtle abnormalities in shape of ectopic beats become clearly *** of how to train the network for use in a clinical environment are given utilising a new parameter,the variance ratio. Results for a study of a combination of algorithms to produce a robust ectopic beat detector are presented. Finally we discuss an on-line implementation for patient-specific adaptability.

关键词： Auto-associative Arrhythmia ECG Ectopic Electrocardiogram neural network QRS Detection

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LC-MS分析普洱茶和茯砖茶与红茶成分的比较研究

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茶叶科学 2006年第3期26卷 191-194页

作者：朱旗 M.n.clifford 毛清黎邓放明湖南农业大学园艺园林学院湖南长沙410128 萨里大学生物科学院

采用LC-MS分析方法,对普洱茶和茯砖茶进行分析与已鉴定的红茶成分进行对比,结果表明,同属黑茶类的普洱茶和茯砖茶具类似的UV图谱,表明二者具有相似的物质成分;普洱茶和茯砖茶不同于红茶,不具有红茶图谱的特征,在380 nm处没有茶红素和茶... 详细信息

采用LC-MS分析方法,对普洱茶和茯砖茶进行分析与已鉴定的红茶成分进行对比,结果表明,同属黑茶类的普洱茶和茯砖茶具类似的UV图谱,表明二者具有相似的物质成分;普洱茶和茯砖茶不同于红茶,不具有红茶图谱的特征,在380 nm处没有茶红素和茶黄素吸收峰的特征,也说明采用红茶的分析方法,不适合分析黑茶;虽然在UV图谱中看不到一些成分的吸收峰,但仍有微量存在,能用MS进行检测。

关键词：普洱茶茯砖茶 LC-MS 成分

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