检索结果-南通市图书馆

Asian pacific Journal of Reproduction 2018年第5期7卷 236-238页

作者： chike f.oguejiofor Department of Veterinary Obstetrics and Reproductive Diseases Faculty of Veterinary MedicineUniversity of NigeriaNsukka 410001Nigeria

Cases of acquired infertility in dogs often have poor prognosis and can be frustrating to clinicians in canine practice. In this case, a 3.5-year-old male Caucasian dog was presented for infertility evaluation. He had no record of successful breeding despite being mated with multiple bitches over a two-year period. Breeding soundness examination was performed including history evaluation, general physical and reproductive system examination, hematology, libido determination, and semen collection, evaluation and screening for infectious organisms. The presence of copious growth of bacteria (Escherichia coli) in conjunction with significant sperm abnormalities and leucospermia was applied to diagnose infertility due to a sub-chronic or chronic bacterial infection of the reproductive tract. Bacterial infection caused significant sperm abnormalities including low sperm motility, increased number of dead sperm and sperm with structural abnormalities such as detached heads, fractured necks, looped tails and coiled tails. Treatment was effected by administering ciprofloxacin orally for 4 weeks.

关键词： Canine infertility Semen evaluation Sperm abnormalities

Importance of Viral Disease in Dairy Cow fertility

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Engineering 2020年第1期6卷 26-33页

作者： D.Claire Wathes chike f.oguejiofor Carole Thomas Zhangrui Cheng Royal Veterinary College Hatfield AL97TAUK faculty of Veterinary Medicine University of NigeriaNsukka 410001Nigeria

Many viral diseases are endemic in cattle populations worldwide. The ability of many viruses to cross the placenta and cause abortions and fetal malformations is well understood. There is also significant evidence that viral infections have additional actions in dairy cows, which are reflected in reduced conception rates. These effects are, however, highly dependent on the time at which an individual animal first contracts the disease and are less easy to quantify. This paper reviews the evidence relating to five viruses that can affect fertility, together with their potential mechanisms of action. Acute infection with non-cytopathic bovine viral diarrhea virus (BVDV) in mid-gestation increases abortion rates or causes the birth of persistently infected calves. BVDV infections closer to the time of breeding can have direct effects on the ovaries and uterine endometrium, which cause estrous cycle irregularities and early embryo mortality. fertility may also be reduced by BVDV-induced immunosuppression, which increases the susceptibility to bacterial infections. Bovine herpesvirus (BHV)-1 is most common in pre-pubertal heifers, and can slow their growth, delay breeding, and increase the age at first calving. Previously infected animals subsequently show reduced fertility. Although this may be associated with lung damage, ovarian lesions have also been reported. Both BHV-1 and BHV-4 remain latent in the host following initial infection and may be reactivated later by stress, for example associated with calving and early lactation. While BHV-4 infection alone may not reduce fertility, it appears to act as a co-factor with established bacterial pathogens such as Escherichia coli and Trueperella pyogenes to promote the development of endometritis and delay uterine repair mechanisms after calving. Both Schmallenberg virus (SBV) and bluetongue virus (BTV) are transmitted by insect vectors and lead to increased abortion rates and congenital ***-8 also impairs t

关键词： Bovine viral diarrhea virus Bovine herpesvirus-1 Bovine herpesvirus-4 Schmallenberg virus Bluetongue virus Immunosuppression Embryo mortality

Consequences of unilateral cryptorchidism on semen and sperm characteristics in West African Dwarf Goats

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Asian pacific Journal of Reproduction 2018年第4期7卷 172-177页

作者： chike f.oguejiofor Izuchukwu S.Ochiogu Okechi L.Okoro Vitalis U.Ogbu Department of Veterinary Obstetrics and Reproductive Diseases Faculty of Veterinary MedicineUniversity of NigeriaNsukka 410001Nigeria

Objective: To evaluate the influence of unilateral cryptorchidism on semen and sperm characteristics in West African Dwarf (WAD) bucks. Methods: Semen was collected using electroejaculator from five unilaterally cryptorchid (UC) and five normal (non-cryptorchid) WAD bucks and analyzed for gross, microscopic and biochemical characteristics. Results:Gross semen evaluation showed no differences between the groups in semen color, viscosity and pH, whereas the normal bucks yielded semen with significantly higher specific gravity (P=0.0436) and volume (P=0.0388) than the UC group. following semen microscopic evaluation, the percentage of sperm vitality (live sperm) was not significantly different between both groups. However, UC bucks yielded semen with significantly lower sperm motility (P=0.0387), sperm concentration per mL (P=0.0020) and total sperm count per ejaculate (P=0.0074). The percentage total sperm abnormality was also higher (Pf UC goats. Abnormalities observed included sperm with cytoplasmic droplets, looped tails, coiled tails and tailless heads. Sperm morphometry showed no differences in the sperm head length and head width between the groups. Biochemical semen evaluation did not reveal any differences between the groups in the concentration of seminal plasma total protein, catalase activity and lipid peroxidation level. Conclusions: Unilateral cryptorchidism significantly affected the quantity and quality of semen and spermatozoa in affected WAD bucks. Due to the hereditary attribute of the condition, it is recommended that animals with this condition should not be used in breeding to forestall increasing prevalence of cryptorchidism in goats.

关键词： Cryptorchidism Goat Semen Spermatozoa

Assessment of SoilGrids data for soil erosion estimation at watershed scale:A case study in northern Thailand

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Pedosphere 2024年第04期 797-813页

作者： chike Onyeka MADUEKE Dhruba Pikha SHRESTHA Panagiotis NYKTAS Department of Natural Resources Faculty of Geo-information Science and Earth Observation (ITC) University of Twente Department of Soil Science and Land Resources Management Nnamdi Azikiwe University Department of Applied Earth Sciences Faculty of Geo-information Science and Earth Observation (ITC) University of Twente

Soil erosion has been identified as one of the most destructive forms of land degradation, posing a threat to the sustainability of global economic, social and environmental systems. This underscores the need for sustainable land management that takes erosion control and prevention into consideration. This requires the use of state-of-the-art erosion prediction models. The models often require extensive input of detailed spatial and temporal data, some of which are not readily available in many developing countries, particularly detailed soil data. The soil dataset Global Gridded Soil Information(SoilGrids) could potentially fill the data gap. Nevertheless, its value and accuracy for soil erosion modelling in the humid tropics is still unknown, necessitating the need to assess its value vis-à-vis field-based data. The major objective of this study was to conduct a comparative assessment of the value of SoilGrids and field-based soil data for estimating soil loss. Soil samples were collected from five physiographic positions(summit, shoulder, back slope, foot slope, and toe slope) using the soil catena approach. Samples were collected using a 5-cm steel sample ring(undisturbed) and a spade(disturbed). Data of the landform, predominant vegetation types, canopy cover, average plant height, land use, soil depth, shear strength, and soil color were recorded for each site. The soil samples were subjected to laboratory analysis for saturated hydraulic conductivity, bulk density, particle size distribution, and organic matter content. Pedotransfer functions were applied on the SoilGrids and field-based data to generate soil hydrological properties. The resultant field-based data were compared with the SoilGrids data for corresponding points/areas to determine the potential similarities of the two datasets. Both datasets were then used as inputs for soil erosion assessment using the revised Morgan-Morgan-finney model. The results from both datasets were again compared to det

关键词：

Seasonal Sodium Percentage (%NA), Absorption Ratio (SAR) and Irrigation Water Quality Index (IWQI) Determination for Irrigation Purposes Along River Ethiope, Southern Nigeria

同方期刊数据库评论

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Journal of Water Resource and Protection 2024年第7期16卷 523-537页

作者： Ochuko Ushurhe famous Ozabor Wekpe Vremudia Onyeayana Obisesan Adekunle Ifuwe Chineme Christabel Dibosa francis chike Department of Environmental Management and Toxicology Dennis Osadebay University Asaba Nigeria School of Environment Geography and Geosciences University of Portsmouth Portsmouth United Kingdom Mabisel Trading and Construction Company Limited Portharcourt Nigeria Department of Surveying and Geo-Informatics Dennis Osadebay University Asaba Nigeria Department of Urban and Regional Planning Dennis Osadebay University Anwai Asaba Nigeria

The improvement of agriculture through irrigation farming is now of great need in the country Nigeria and Delta State. The country is going through a phase of famine and food insecurity caused by climate change and rain dependent agricultural practices. The aim of the study therefore, was to evaluate the quality of water from River Ethiope in Southern Nigeria for irrigation agriculture purposes using the percentage sodium (%Na), sodium-adsorption ratio (SAR) and irrigation-water quality index (IWQ1) techniques. The study deployed the experimental design and water samples were collected from different segments of the Ethiope River. A total of 144 water samples were collected and analysed for physicochemical parameters quality (EC, HCO3, Cl−, Na+, Mg2+, Ca2+ and K+) from January to December, 2022. The results showed that all the calculated values for %Na were within the classified rating of 20 f 0 f IWQI were within the range of 70 - 55 and 55 - 40. This implies that the water is good to doubtful for %Na, excellent for SAR and of moderate and high restrictions for IWQI. Water was adjudged to be good for irrigation activities, and should be applicable in areas with moderate and high soil permeability. The routine testing of the water to ascertain physicochemical parameters quality regularly, in order not to affect its use for irrigation was among the recommendations. This finding herein shall be of use to Water Resources and Agriculture ministries in Nigeria.

关键词： Evaluation Irrigation-Agriculture IWQI River-Ethiope SAR %Na

Antifertility effects of Azadirachta indica methanol seed extract on canine spermatozoa in vitro

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Asian pacific Journal of Reproduction 2020年第3期9卷 135-141页

作者： chike fidelis oguejiofor Ifeanyi Gabriel Eke Kenneth Orji Anya 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 the effects of Azadirachta(A.)indica methanol seed extract on canine male fertility in ***:The effect of the *** methanol seed extract(2.5,5.0,10.0 and 20.0 mg/mL,respectively)on canine spermatozoa was evaluated in vitro at 1.0,2.5,5.0 and 10.0 min *** two controls were comprised of sperm sample in phosphate-buffered saline,and sperm sample in phosphate-buffered saline and 1%dimethyl sulfoxide,*** experiment was repeated(n=3)in duplicates with semen collected from 3 adult *** effect of *** methanol seed extract treatments on canine spermatozoal total and progressive motility(phase-contrast microscopy),sperm vitality(eosin-nigrosin vital staining method)and total abnormalities(phase contrast microscopy,eosin-nigrosin staining and Papanicolaou staining methods)were ***:*** methanol seed extract treatment caused a concentration and time-dependent decrease in sperm percentage total motility,progressive motility and *** absence of sperm revival post-treatment provided evidence of a permanent or irreversible incapacitation of sperm by *** methanol seed ***:The inhibition of sperm motility and significant spermicidal effect observed post-treatment suggest that *** methanol seed extract may produce a potent antifertility or contraceptive effect in dogs if applied as an intra-vaginal cream pre-coitus.

关键词： Antifertility Azadirachta indica Canine Spermatozoa Contraceptive

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

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

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

急性髓系白血病细胞条件培养液对间充质干细胞的生物学影响

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

中国组织工程研究 2024年第31期28卷 4995-5002页

作者：张弛可王飞清吴丹杨波成金阳陈娟唐东昕刘洋李艳菊贵州医科大学贵州中医药大学第一附属医院贵州医科大学细胞工程生物医药技术国家地方联合工程实验室贵州医科大学附属医院血液科

背景：目前，关于急性髓系白血病骨髓微环境中的骨髓间充质干细胞生物学功能及分子改变尚不完全清楚。目的：综合生物信息学和细胞实验探究急性髓系白血病患者来源骨髓间充质干细胞的生物学功能改变，并探讨急性髓系白血病细胞条件培养... 详细信息

背景：目前，关于急性髓系白血病骨髓微环境中的骨髓间充质干细胞生物学功能及分子改变尚不完全清楚。目的：综合生物信息学和细胞实验探究急性髓系白血病患者来源骨髓间充质干细胞的生物学功能改变，并探讨急性髓系白血病细胞条件培养液在其中的作用。方法：从GEO数据集中筛选差异基因进行富集分析，并构建蛋白质互作网络和获取Hub基因。培养急性髓系白血病患者和健康供者的骨髓间充质干细胞，使用急性髓系白血病细胞条件培养液处理健康供者的骨髓间充质干细胞，对各组细胞进行成脂诱导分化、成骨诱导分化、β-半乳糖苷酶染色、细胞周期检测和Hub基因的验证。结果与结论：(1)从GSE84881中获取急性髓系白血病患者和健康供者的骨髓间充质干细胞基因表达数据，筛选出184个上调基因和140个下调基因。(2)富集的生物学功能主要包括细胞周期、脂肪细胞分化、细胞代谢过程和MYC通路。根据Degree算法筛选出上调的10个Hub基因和下调的10个Hub基因。(3)通过体外细胞实验发现，与健康供者的骨髓间充质干细胞相比，急性髓系白血病患者骨髓间充质干细胞表面抗原未发生改变，但其成脂分化能力增强、成骨分化能力减弱、β-半乳糖苷酶阳性细胞数增多、细胞形态改变、细胞周期停滞、LGALS3表达增加以及MYC表达降低。经急性髓系白血病细胞条件培养液培养后，健康供者骨髓间充质干细胞出现相似改变。(4)结果表明，急性髓系白血病患者骨髓微环境中的间充质干细胞生物学功能发生改变，这为骨髓间充质干细胞与肿瘤的交互作用提供新的见解。

关键词：急性髓系白血病骨髓间充质干细胞条件培养液 GEO数据库生物信息学

Effect of process parameters on the density and porosity of laser melted AlSi10Mg/SiC metal matrix composite

同方期刊数据库评论

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

frontiers of Mechanical Engineering 2018年第4期13卷 520-527页

作者： Omotoyosi H. fAMODIMU Mark STANfORD chike f. ODUOZA Lijuan ZHANG faculty of Science and Engineering School of Engineering Telford Campus University of Wolverhampton WV1 1LY Wolverhampton UK

Laser melting of aluminium alloy-AlSi10Mg has increasingly been used to create specialised products in various industrial applications, however, research on utilising laser melting of aluminium matrix composites in replacing specialised parts have been slow on the uptake. This has been attributed to the complexity of the laser melting process, metal/ceramic feedstock for the process and the reaction of the feedstock material to the laser. Thus, an understanding of the process, material microstructure and mechanical properties is important for its adoption as a manufacturing route of aluminium metal matrix composites. The effects of several parameters of the laser melting process on the mechanical blended composite were thus investigated in this research. This included single track formations of the matrix alloy and the composite alloyed with 5% and 10% respectively for their reaction to laser melting and the fabrication of density blocks to investigate the relative density and porosity over different scan speeds. The results from these experiments were utilised in determining a process window in fabricating near-fully dense parts.

关键词： selective laser melting additive manufacturing mechanical alloying powder metallurgy aluminium metal matrix composite

Bovine Endometrial Cells Mount Innate Immune Response to the Intracellular Ligands CL097 and Poly(dA:dT) Indicating Roles against Uterine Viruses

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Open Journal of Animal Sciences 2017年第2期7卷 110-126页

作者： chike f. oguejiofor Zhangrui Cheng Ali A. fouladi-Nashta D. Claire Wathes Department of Production and Population Health Royal Veterinary College North Mymms UK Department of Comparative Biomedical Sciences Royal Veterinary College North Mymms UK

Uterine infection and endometritis cause infertility and economic losses in the cattle industry. The innate immune response of the endometrium is critical in the elimination of pathogenic organisms that invade the uterus in postpartum cows. This study investigated the response of bovine endometrium to synthetic intracellular ligands which activate innate immunity by stimulating similar receptors to those used to recognise the presence of some viruses. Mixed primary epithelial and stromal cell cultures were treated with 5 μg/ml of CL097 (a TLR7/8 ligand) or 2 μg/ml of poly(dA:dT) (a DNA analogue) for either 6 h or 24 h. Cellular responses were assessed by the mRNA expression of 18 immune-related genes and 3 endogenous reference genes by conventional PCR followed by qRT-PCR from four replicate experiments. Bovine endometrial cells expressed the cytosolic pattern recognition receptors (PRRs) DDX58 (RIG-I), IfIH1 (MDA5) and LRRfIP1 which act as intracellular nucleic acid sensors. Neither ligand altered the expression of the extra-cytosolic pattern recognition receptors (PRRs) TLR3, TLR4, TLR7 or TLR8 whereas poly(dA:dT) treatment increased the expression of IfIH1 and DDX58. Treated cells also responded to CL097 or poly(dA:dT) with a differential up-regulation of genes involved in innate immune response including type I interferon/antiviral response (MX1, IfNAR1), antimicrobial activity (MUC1, SLPI) and cytokine activity (TNf, IL1B, IL8). Bovine endometrial cells therefore express both cytosolic and extra-cytosolic intracellular PRRs and are able to mount an innate immune response upon stimulation with intracellular ligands. This suggests an important role for these cells in the defence against viruses that may be present in the uterus in postpartum cows.

关键词： Endometrium Innate Immunity Intracellular Ligands Gene Expression