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Alleviating effects of melatonin on oxidative changes in the testes and pituitary glands evoked by subacute chlorpyrifos administration in Wistar rats 被引量:5
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作者 Angela J Umosen Suleiman F Ambali +2 位作者 Joseph O Ayo Bisala Mohammed Chidiebere Uchendu 《Asian Pacific Journal of Tropical Biomedicine》 SCIE CAS 2012年第8期645-650,共6页
Objective:To evaluate the alleviating effects of melatonin on oxidative changes in the testes and pituitary gland induced by subacute chlopyrifos(CPF) exposure in rats.Methods:Forty adult male Wistar rats divided in... Objective:To evaluate the alleviating effects of melatonin on oxidative changes in the testes and pituitary gland induced by subacute chlopyrifos(CPF) exposure in rats.Methods:Forty adult male Wistar rats divided into 4 groups of 10 animals were used for the study.Croup I received soya oil(2 mL/kg) while group II was administered with melatonin(0.5 mg/kg).Group III was administered CPF only(8.5 mg/kg <sup> </sup>l/10th of the LD<sub>50</sub>) while group Ⅳ was pretreated with melatonin(0.5 mg/kg) and then exposed to CPF(8.5 mg/kg),10 min later.The regimens were administered by gavage once daily for a period of 28 d.At the end of the exposure period, the rats were sacrificed and the testicular tissues and pituitary glands were evaluated for the malonaldehyde(MDA) concentration and activities of superoxide dismutase(SOD) and catalase(CAT).Results:CPF increased MDA concentrations and reduced the activities of SOD and CAT in the testes and pituitary gland.Melatonin pretreatment reduced the testicular and pituitary MDA concentrations and improves the SOD and CAT activities.Conclusions:the study showed that subacute CPF-induced oxidative stress in the testes and pituitary glands were alleviated by melatonin due to its antioxidant property. 展开更多
关键词 CHLORPYRIFOS OXIDATIVE stress testes Pituitary GLANDS Alleviation MELATONIN
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Expression of toxin-related human mono-ADP-ribosyltransferase 3 in human testes 被引量:4
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作者 Maik Friedrich Andreas Grahnert +3 位作者 Uwe Paasch Andrea Tannapfel Friedrich Koch-Nolte Sunna Hauschildt 《Asian Journal of Andrology》 SCIE CAS CSCD 2006年第3期281-287,共7页
Aim: To investigate wether the corresponding protein of mono-ADP-ribosyltransferase 3 (ART3) mRNA is expressed in human testes and, if so, whether the expression is cell type-specific. Methods: ART3 mRNA was deter... Aim: To investigate wether the corresponding protein of mono-ADP-ribosyltransferase 3 (ART3) mRNA is expressed in human testes and, if so, whether the expression is cell type-specific. Methods: ART3 mRNA was determined in human testes and sperm by reverse transcription-polymerase chain reaction (RT-PCR). The glycosylphosphatidylinositol linkage of ART3 was shown by treating ART3-transfected HEK-293-T cells with phospholipase C. Fluorescent activated cell sorter (FACS)-analyses were used to detect ART3 on mature spermatozoa and immunohistological studies to detect the protein in testes. Results: ART3 protein was shown to be present in testes. It was found on spermatocytes only. It was absent from spermatogonia, spermatids and spermatozoa. The absence of ART3 from spermatozoa was confirmed by FACS-analysis. ART3 protein was detected neither within a seminoma nor on Leydig cells. Conclusion: Here we show for the first time that ART3 protein is expressed in testes in particular on spermatocytes, indicating that ART3 exerts a specific function only required at a particular stage of spermatogenesis. 展开更多
关键词 mono-ADP-ribosyltransferase 3 testes human spermatocyte SPERMATOGENESIS
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Asymmetry of Testes in Guenther's Frog,Hylarana guentheri(Anuar:Ranidae) 被引量:3
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作者 Yanhong LIU Wenbo LIAO +2 位作者 Caiquan ZHOU Zhiping MI Min MAO 《Asian Herpetological Research》 SCIE 2011年第4期234-239,共6页
Testes size in most animals commonly shows directional asymmetry. In birds, the left testis mass is usually larger than the right one, but the reports on the testes asymmetry in anurans are very few. Moller (1994) h... Testes size in most animals commonly shows directional asymmetry. In birds, the left testis mass is usually larger than the right one, but the reports on the testes asymmetry in anurans are very few. Moller (1994) hypothesized that the right testis serves a compensatory role and increases in size when the left one is defective, and further suggested that testes asymmetry may be a reliable indicator of individual body condition. In this paper, we tested the compensation hypothesis in the Guenther's frog, Hylarana guentheri. From 60 sampled males, we found that there was a significant directional asymmetry in testes mass, with the left testis size being significantly correlated with relative testes asymmetry, providing evidence that the right testis had a compensatory function. However, testes mass and asymmetry were not correlated with body condition. Hence, we found no evidence that testes asymmetry in the Guenther's frog reflected male condition, and male age was also not related to testes mass or asymmetry. 展开更多
关键词 directional testes asymmetry compensation hypothesis body condition Hylarana guentheri
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Induction of Apoptosis in the Immature Mouse Testes by a Mixture of Melamine and Cyanuric Acid 被引量:1
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作者 YOU Hua ZHU Jin-feng +9 位作者 SHE Rui-ping CHANG Ling-ling SHI Rui-han DING Ye CHI Li-juan LIU Bin YUE Zhuo TIAN Ji-jing MAO Jing-jing SU Li-fang 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2012年第12期2058-2066,共9页
The toxicity of melamine has attracted much attention since the recent outbreaks of renal injury in pets and infants. Previous studies indicated that melamine by itself had low toxicity, whereas a mixture of melamine ... The toxicity of melamine has attracted much attention since the recent outbreaks of renal injury in pets and infants. Previous studies indicated that melamine by itself had low toxicity, whereas a mixture of melamine and cyanuric acid (M+CA) could cause serious renal damage. At present, most researches on the toxicity of M+CA are focused on the kidney. However, little is known about the adverse effects of this mixture on the reproductive system. In the present study, the toxicity of M+CA to testes was investigated. Immature male mice were orally dosed with 0, 0.6, 3, and 15 mg kg-1 d-1 of a 1:1 M+CA for 28 d. Pathological changes occurred in germ cells, such as loose arrangement, reduced numbers and karyopyknosis, indicating that this mixture was toxic to spermatogenesis. Compared with the control group, the TUNEL- positive germ cells increased significantly and the ratio of Bcl-2 to Bax, total antioxidant capacity and superoxide dismutase activity decreased significantly in the 3 and 15 mg kg-1 d- M+CA treated group, while the activities of caspase-3, caspase- 8 and caspase-9 remained unchanged. The results suggest that M+CA can induce apoptosis in the mice testes. The downregulation of Bcl-2/Bax and oxidative stress may play a pivotal role in the induction of apoptosis by M+CA in mice testes. 展开更多
关键词 melamine/cyanuric acid mixture testes injury caspase-independent apoptosis
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Inhibitory Effect of Aqueous Extract of Moringa oleifera and Newbuoldia laevis Leaves on Ferrous Sulphate and Sodium Nitroprusside Induced Oxidative Stress in Rat’s Testes in Vitro 被引量:2
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作者 Seun F. Akomolafe Ganiyu Oboh +2 位作者 Afolabi A. Akindahunsi Ayodele J. Akinyemi Olusola Adeyanju 《Open Journal of Medicinal Chemistry》 2012年第4期119-128,共10页
Oxidative stress has been identified as one of the factors that affects fertility status. Therefore, this study sought to investigate the inhibitory effect of aqueous extract of Moringa oleifera and Newbuoldia laevis ... Oxidative stress has been identified as one of the factors that affects fertility status. Therefore, this study sought to investigate the inhibitory effect of aqueous extract of Moringa oleifera and Newbuoldia laevis leaves on FeSO4 and Sodium Nitroprusside (SNP) induced lipid peroxidation in rat testes in vitro. Incubation of the testes tissue homogenate in the presence of FeSO4 and SNP caused a significant increase in the malondialdehyde (MDA) contents of the testes. The aqueous extract from both Moringa oleifera and Newbuoldia laevis leaves caused a significant decrease in the MDA contents of the testes in a dose-dependent manner. However, aqueous extract from Moringa oleifera leaf (EC50 = 0.29 mg/ml) had a significant (P2+ induced lipid peroxidation in the rat testes homogenate than that of Newbuoldia laevis leaf extract (EC50 = 0.58 mg/ml);while there was no significant (P2+ chelating and reducing power. Therefore, these plants have potential to prevent oxidative stress in testes and improve fertility outcomes. 展开更多
关键词 LIPID PEROXIDATION MALONDIALDEHYDE Antioxidant Activity testes
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Growth and Development of Testes in Domesticated and Hybrid(wild × domesticated)Yak Bulls
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作者 Yan Ping Pan Heping Zhi Dejuan 《中国草食动物》 2005年第z2期26-30,共5页
Testicular tissue was studied in domesticated yak and in wild yak × domesticated yak(F1 and F2)bulls at 6,12,18 and 24 months of age by stereology for quautitative histology and by comparative studies on the lact... Testicular tissue was studied in domesticated yak and in wild yak × domesticated yak(F1 and F2)bulls at 6,12,18 and 24 months of age by stereology for quautitative histology and by comparative studies on the lactate dehydrogenase(LDH)isoenzyme spectrum, LDH activity and the percentage content of LDH isoenzymes in testes. The results indicated that all three types of yak were similar in both the characteristics of ultrastructure of testicular tissue and the degree of germ cell development. The process of spermatogenesis was initiated and sperm were produced for the first time at the age of 12months in all three yak types. All yak types exhibited similar age-related, increases in weight of testes,volume density of both the seminiferous tubules and seminiferous epithelium and height of seminiferous epithelium but all these indexes were slightly affected by season. The number of LDH isoenzyme bands after electrophoresis varied with age as follows: four bands were present at 6 months of age, five bands at 12 and 18 months and six bands at 24 months of age. The sixth band was LDH -x ,which appeared between the LDH4 and LDH5 band. These results indicated that yak bulls reach sexual maturity at 24months of age and that puberty is not affected by infusion of wild strains. 展开更多
关键词 HISTOLOGY LACTATE dehydragenase testes ULTRASTRUCTURE Yaks.
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Histomorphometry of the Testes, Epididymides, and Spermatozoa of Four Indigenous Breeds of Bulls in Ibadan, Nigeria
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作者 Ayodeji Ayotunde Oni Matthew Olugbenga Oyeyemi Joseph Atawalna 《Open Journal of Veterinary Medicine》 2021年第9期299-306,共8页
Forty testicles were used to carry out histomorphometry study on the testes, epididymides and spermatozoa of four indigenous breeds of bull found in Ibadan (Red Bororo (RB), Sokoto Gudali (SG), White Fulani (WF) and D... Forty testicles were used to carry out histomorphometry study on the testes, epididymides and spermatozoa of four indigenous breeds of bull found in Ibadan (Red Bororo (RB), Sokoto Gudali (SG), White Fulani (WF) and Dhali (DL)<span style="font-family:;" "="">)</span><span style="font-family:;" "="">. The testicles were harvested immediately after the slaughter at the Bodija abattoir and transported to the laboratory in an insulated flask containing warm water at 37<span style="color:#4F4F4F;font-family:-apple-system, " font-size:16px;white-space:normal;background-color:#ffffff;"="">°</span>C within 30 minutes. In the laboratory, the samples were dissected and histological sections of the right testis, right and left caudal epididymides taken from two bulls in each group. The tissues were fixed in Bouin’s fluid. They were processed in an automatic tissue processor, embedded in paraffin wax using the embedding system (Leica EG 1160) and sectioned with microtome at 4 microns. The sections were then stained by <span>Haematoxylin and Eosin method and mounted and examined under a microscope. There was no significant difference between breed and seminiferous</span> tubular diameter (STD) and testicular germinal height (TGEH). The mean STD ranged from 223.00 ± 28.35 to 316.00 ± 37.70 μm, while the TGEH ranged from 81.60 ± 10.05 to 89.80 ± 4.83 μm. The mean epididymal tubular diameters (ETD) and epididymal lumen diameters (ELD) had the highest value of 378.00 ± 10.95 and 298.20 ± 26.0489 μm in DL and lowest of 373.80 ± 37.70 and 278.10 ± 27.71 μm in RB, respectively. The mean epididymal germinal epithelia heights (EGEH) were highest (61.20 ± 5.70 μm) in WF and lowest (39.80 ± 0.86 μm) in RB. The mean sperm head length (SHL), sperm midpiece length (SMPL), sperm tail length (STL) and sperm total length (TL) had the highest values of 5.90 ± 0.10, 8.80 ± 0.25, 24.20 ± 2.59 and 38.90 ± 2.94 μm, respectively in SG. SHL and SMPL were lowest in DL bulls (5.00 ± 0.00 and 6.30 ± 0.20 μm), while STL and TL were lowest (18.90 ± 0.24 and 31.30 ± 0.85 μm). The results of this study provide baseline data on the histomorphometry of the testes and epididymides and spermatozoa of some indigenous bulls.</span> 展开更多
关键词 HISTOMORPHOMETRY testes EPIDIDYMIS SPERMATOZOA Indigenous Bull
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Ultrastructural Alterations in Testes from Rats Treated with Cysteine
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作者 A.S.BERNACCHI E.C.DEFERREYRA +1 位作者 C.R.DECASTRO J.A.CASTRO 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 1993年第2期172-178,共7页
Cysteinc administration in relatively large doses has been repetitively employed as preventive agent against chemically induced cell injury or as radioprotector. In this work we report that administration of a dose st... Cysteinc administration in relatively large doses has been repetitively employed as preventive agent against chemically induced cell injury or as radioprotector. In this work we report that administration of a dose standard for those purposes (1.9gr/kg, po in water) causes significant ultrastructurally evident alterations in testcs at 24h. Damage involves Scrtoli cells and spermatids. Alterations found in the former include dilatation of nuclear membrane and of the smooth (SER) and rough endoplasmic reliculum (RER) and detachment of ribosomes from RER. Cytoplasm appeared more sparse and electron lucent than in controls and contained more lipid droplets and lysosomcs. Mitochondria exhibited alterations in shape and size.Damage in spermatids consisted of the appearance of irregular shape of the nucleus and alterations in their acrosomal caps. There was no histochemical evidence for either calcium accumulation or lipid peroxidation occurrence in testes of cysteine-trcated animals. Results indicate that the large doses of cysteine employed in prevention of radiation or chemical effects is able to cause injury to Sertoli cells of the testes. Damage observed does not reach irreversible stages but may be sufficient to lead to production of abnormal spermatids. 展开更多
关键词 Ultrastructural Alterations in testes from Rats Treated with Cysteine
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The Danger within:Covid-19 Affinity for ACE2 Receptors in Adipose Tissue and Testes.The Protective Effects of Estradiol,Fitness,and Weight Management
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作者 Xanya Sofra 《Journal of Endocrinology Research》 2020年第1期1-14,共14页
The imminent danger of the Covid-19 pandemic has accelerated research in pharmaceuticals that either target the viral Spike proteins fusion with ACE2 receptors,or the infectious RNA replication that often overwhelms i... The imminent danger of the Covid-19 pandemic has accelerated research in pharmaceuticals that either target the viral Spike proteins fusion with ACE2 receptors,or the infectious RNA replication that often overwhelms immune defences.The scope of this review was to elucidate the main human vulnerabilities to Covid-19,including the accumulation of ACE2 receptors in testes,adipose tissue,thyroid,heart and kidneys that escalate viral affinity in males,the aged,and certain medical conditions,including diabetes,CVD,and pulmonary diseases.Pre-existing inflammation inherent in obesity may exacerbate the“cytokine storm,”a rampaging immune reaction during the course of Covid-19 that is deleterious to the host.We examined the molecular dynamics illustrating the action of new therapeutics necessary for Covid-19 patients;the estradiol advantage hypothesis;alternative therapies including hormone replacement procedures and mesenchymal stem cells;plus preventive and protective interventions.The current perspective also explored the primary components of dysregulated health predisposing individuals to Covid-19,including hormonal imbalance,increased lipids and lipoproteins,thyroid dysfunction,degraded fitness,and age-related testosterone decline accompanied by cortisol increase that provokes stress eating behaviours and weight accumulation.Obesity increases the probability of Covid-19 infection due to its abundance of ACE2 receptors;while physical activity may decrease Covid-19 vulnerability,by reducing fat and increasing muscle mass that manifests a relatively inhibited ACE2 expression.Several weight management solutions feature lasers and radiofrequency which diminish subcutaneous adiposity but do not enhance fitness.A data metanalysis of seven recently published clinical studies on 95 obese individuals,73 males and 22 females with an average BMI of 30.9,demonstrated visceral fat reduction combined with increased skeletal muscle mass.It also revealed a statistically significant decrease in BMI,lipids,lipoproteins,inflammation and toxicity as measured by CRP,Creatinine and Bilirubin respectively,juxtaposed by optimally healthier levels of Cortisol,Testosterone,Free T3,IGF-1,Insulin,and the appetite controlling hormones Leptin and Ghrelin. 展开更多
关键词 Visceral Adipose Tissue ACE2 testes Covid-19 ESTRADIOL FITNESS Weight management Leptin Free T3 Testosterone BMI BMR VLDL Triglycerides HDL Creatinine Bilirubin Ghrelin Insulin IGF-1 Cortisol CRP Diabetes PREDIABETES HYPERPHAGIA
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Biological Effects of Deer Semen on Development of Testes in Mice 被引量:1
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作者 Lian Zhengxing, Li Wu (Northeast Agricultural University, Harbin 150030, PRC) 《Journal of Northeast Agricultural University(English Edition)》 CAS 1997年第1期52-54,共3页
immature male mice were selected in the experiment to assess the effects of Deer semen on the development of testes. 20 mice were fed with 0.05 mL semen·d -1 for 15 days and the rest fed with the same volume... immature male mice were selected in the experiment to assess the effects of Deer semen on the development of testes. 20 mice were fed with 0.05 mL semen·d -1 for 15 days and the rest fed with the same volume of albumeh for the same period as controls. The relative weight of testis to body weight was higher in treated group than that in the control (P<0.05), so was the volume of testis (P<0.05). The density of testis was lower in treated group than in the control (P<0.05). Eighty percent of mice in the treated group showed the appearance of tubule cavity and spermatozoa in the testis, but only about 20% in the control. It was concluded that the Deer semen had improvement effects on the development of testes and sexual maturity of mice. 展开更多
关键词 SEMEN testes deer MOUSE
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原发性颈淋巴结结核诊治分析
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作者 吴楷元 黄琦 +3 位作者 邬振华 谢如姣 周磊 王淼 《中国耳鼻咽喉头颈外科》 CSCD 2024年第2期129-130,共2页
目的探讨原发性颈淋巴结结核的临床特征、确诊方式及诊疗方案。方法回顾性分析宁波市医疗中心李惠利医院确诊的39例原发性颈淋巴结结核患者临床资料,总结其临床特点、治疗方法及随访情况。结果所有患者均以颈部无痛性质韧肿块为首发症状... 目的探讨原发性颈淋巴结结核的临床特征、确诊方式及诊疗方案。方法回顾性分析宁波市医疗中心李惠利医院确诊的39例原发性颈淋巴结结核患者临床资料,总结其临床特点、治疗方法及随访情况。结果所有患者均以颈部无痛性质韧肿块为首发症状,肿块多位于颈部Ⅲ、Ⅳ、Ⅴ区,部分位于Ⅰ、Ⅱ区,均完善CT、MRI或B超等检查。根据影像学检查和临床经验,21例患者行结核菌素试验(PPD)或结核感染T细胞斑点试验(T-SPOT),其中2例PPD阳性,13例T-SPOT阳性,15例均经穿刺病理结果确诊,6例经手术病理确诊;1例经细针穿刺细菌培养发现结核杆菌确诊;17例影像学考虑肿瘤性病变,经颈淋巴结清扫或肿块部分切除术后病理确诊结核。39例患者均予标准抗结核治疗半年,随访1年未见复发。结论原发性颈淋巴结结核缺乏特异性症状,初步诊断可借助T-SPOT检查,确诊仍需结核杆菌培养阳性、穿刺细胞学或组织病理结果,治疗应采用世界卫生组织(WHO)推荐的6个月治疗方案,当伴有脓肿、窦道或溃疡型结核时,应结合手术治疗,可有效缩短术后抗结核治疗时间、减少药物用量及不良反应。 展开更多
关键词 颈(Neck) 结核 淋巴结(Tuberculosis Lymph Node) 结核菌素试验(Tuberculin Test)
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Lateral earth pressure of granular backfills on retaining walls with expanded polystyrene geofoam inclusions under limited surcharge loading 被引量:1
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作者 Kewei Fan Guangqing Yang +2 位作者 Weilie Zou Zhong Han Yang Shen 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2024年第4期1388-1397,共10页
Existing studies have focused on the behavior of the retaining wall equipped with expanded polystyrene(EPS)geofoam inclusions under semi-infinite surcharge loading rather than limited surcharge loading.In this paper,t... Existing studies have focused on the behavior of the retaining wall equipped with expanded polystyrene(EPS)geofoam inclusions under semi-infinite surcharge loading rather than limited surcharge loading.In this paper,the failure mode and the earth pressure acting on the rigid retaining wall with EPS geofoam inclusions and granular backfills(henceforth referred to as EPS-wall),under limited surcharge loading are investigated through two-and three-dimensional model tests.The testing results show that different from the sliding of almost all the backfill in the EPS-wall under semi-infinite surcharge loading,only an approximately triangular backfill slides in the wall under limited surcharge loading.The distribution of the lateral earth pressure on the EPS-wall under limited surcharge loading is non-linear,and the distribution changes from the increase of the wall depth to the decrease with the increase of the limited surcharge loading.An approach based on the force equilibrium of a differential element is developed to predict the lateral earth pressure behind the EPS-wall subjected to limited surcharge loading,and its performance was fully validated by the three-dimensional model tests. 展开更多
关键词 Retaining wall Expanded polystyrene(EPS)geofoam Limited surcharge loading Lateral earth pressure Model test Prediction
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A dual-RPA based lateral flow strip for sensitive,on-site detection of CP4-EPSPS and Cry1Ab/Ac genes in genetically modified crops 被引量:1
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作者 Jinbin Wang Yu Wang +7 位作者 Xiuwen Hu Yifan Chen Wei Jiang Xiaofeng Liu Juan Liu Lemei Zhu Haijuan Zeng Hua Liu 《Food Science and Human Wellness》 SCIE CSCD 2024年第1期183-190,共8页
Traditional transgenic detection methods require high test conditions and struggle to be both sensitive and efficient.In this study,a one-tube dual recombinase polymerase amplification(RPA)reaction system for CP4-EPSP... Traditional transgenic detection methods require high test conditions and struggle to be both sensitive and efficient.In this study,a one-tube dual recombinase polymerase amplification(RPA)reaction system for CP4-EPSPS and Cry1Ab/Ac was proposed and combined with a lateral flow immunochromatographic assay,named“Dual-RPA-LFD”,to visualize the dual detection of genetically modified(GM)crops.In which,the herbicide tolerance gene CP4-EPSPS and the insect resistance gene Cry1Ab/Ac were selected as targets taking into account the current status of the most widespread application of insect resistance and herbicide tolerance traits and their stacked traits.Gradient diluted plasmids,transgenic standards,and actual samples were used as templates to conduct sensitivity,specificity,and practicality assays,respectively.The constructed method achieved the visual detection of plasmid at levels as low as 100 copies,demonstrating its high sensitivity.In addition,good applicability to transgenic samples was observed,with no cross-interference between two test lines and no influence from other genes.In conclusion,this strategy achieved the expected purpose of simultaneous detection of the two popular targets in GM crops within 20 min at 37°C in a rapid,equipmentfree field manner,providing a new alternative for rapid screening for transgenic assays in the field. 展开更多
关键词 Genetically modifi ed crops On-site detection Lateral fl ow test strips Dual recombinase polymerase amplification (RPA)
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Aquifer Test求群孔抽水试验水文地质参数
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作者 李红伟 《中国高新科技》 2024年第5期56-57,129,共3页
在水文地质条件复杂的地区,往往采用大型的群孔抽水试验充分揭露含水层特征,获取水文地质参数。用Aquifer Test软件求解水文地质参数,则方便实用、简捷高效,可快速输出拟合图形和求参结果。Aquifer Test提供了丰富的求参方案,求参必须... 在水文地质条件复杂的地区,往往采用大型的群孔抽水试验充分揭露含水层特征,获取水文地质参数。用Aquifer Test软件求解水文地质参数,则方便实用、简捷高效,可快速输出拟合图形和求参结果。Aquifer Test提供了丰富的求参方案,求参必须结合当地当时的水文地质条件实际情况考虑,选择适合的方案和时空数据求取水文地质参数。 展开更多
关键词 群孔抽水试验 水文地质参数 Aquifer Test
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Wolbachia-induced expression of kenny gene in testes affects male fertility in Drosophila melanogaster 被引量:1
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作者 John C.Biwot Hua-Bao Zhang +3 位作者 Chen Liu Jun-Xue Qiao Xiao-Qiang Yu Yu-Feng Wang 《Insect Science》 SCIE CAS CSCD 2020年第5期869-882,共14页
Wolbachia are Gram-negative endosymbionts that are known to cause embry-onic lethality when infected male insects mate with uninfected females or with females carrying a different strain of Wolbachia,a situation chara... Wolbachia are Gram-negative endosymbionts that are known to cause embry-onic lethality when infected male insects mate with uninfected females or with females carrying a different strain of Wolbachia,a situation characterized as cytoplasmice incom-patibility(CD).However,the mechanism of CI is not yet fully understood,although re-cent studies on Drosophila melanogaster have achieved great progress.Here,we found that Wolbachia infection caused changes in the expressions of several immunity-related genes,including significant upregulation of kenny(key),in the testes of D.melanogaster.Overexpression of key in fly testes led to a significant decrease in egg hatch rates when these fies mate with wild-type females.Wolbachia-infected females could rescue this embryonic lethality.Furthermore,in key overexpressing testes terminal deoxynucleotidyl transferase-mediated dUTP-biotin nick-end labeling signal was significantly stronger than in the control testes,and the level of reactive oxygen species was significantly increased.Overexpression of key also resulted in alterations of some other immunity-related gene expressions,including the downregulation of Zn72D.Knockdown of Zn72D in fly testes also led to a significant decrease in egg hatch rates.These results suggest that Wolbachia might induce the defect in male host fertility by immunity-related pathways and thus cause an oxidative damage and cell death in male testes. 展开更多
关键词 Drosophila melanogaster KEY testes WOLBACHIA Zn72D
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Effect of Combination Regimen of Low-dose Gossypol Acetic Acid with Steroid Hormones on Expression of Protein Kinase C alpha (PKC-α) and Cyclin D1 in Rat Testes 被引量:1
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作者 Jin-hui SHAO Zeng-lu XU +2 位作者 Xiao-jing QIAN Fang LIU Hui HUANG 《Journal of Reproduction and Contraception》 CAS 2012年第4期199-208,共10页
Objective To investigate the contraceptive mechanism of combination regimen of low- dose gossypol acetic acid (GA) with steroid hormones [desogestre/ethinylestradiol/ testosterone undeeanote(DSG/EE/TU)]. Methods A... Objective To investigate the contraceptive mechanism of combination regimen of low- dose gossypol acetic acid (GA) with steroid hormones [desogestre/ethinylestradiol/ testosterone undeeanote(DSG/EE/TU)]. Methods Adult male rats were randomly divided into four groups. Group GH: rats were fed orally with gossypol acetic acid (GA, 12.5 mg/kg) and desogestrel (DSG, 0.125 mg/kg)/ ethinylestradiol (EE, 0.025 mg/kg)/testosterone undecanoate (TU, 100 mg/kg per day, qd X4 weeks or 10 weeks); group G: a single dose of GA (12.5 mg/kg per day, qd X 4 weeks or I0 weeks); group H: the same dosage of DSG/EE/TUas in group GH; group C: rats were treated with vehicle (1% methyl cellulose) as the control. Expression of protein kinase C alpha (PKC-a) and cyclin D1 in rat testes were tested mainly by immunohistochemistry (IHC) and Western blotting. Results IHC results showed that protein PKC- a was expressed mainly in interstitial tissue of testis among seminiferous tubule. The expression of PKC-oc in groups H and GH at week 10 was decreased greatly compared with that in group C. The protein cyclin D1 was expressed mainly in residual body of seminiferous tubule eavosurface and interstitial tissue among seminiferous tubule of testis. Western blotting results showed that the expression of PKC-a in groups H and GH at week 10 was decreased significantly compared with that in group C (P〈0.05). The expression of cyclin D1 in groups G, H or GH at week 10 rose significantly compared with that in group C (P 〈0.05).Conclusion The administration of low-dose gossypol acetic acid with steroid hormones for 10 weeks can decrease the expression of PKC-a greatly. 展开更多
关键词 GOSSYPOL steroid hormones protein kinase C alpha (PKC-a) cyclin D 1 RAT testes
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Failure characterization of fully grouted rock bolts under triaxial testing
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作者 Hadi Nourizadeh Ali Mirzaghorbanali +3 位作者 Mehdi Serati Elamin Mutaz Kevin McDougall Naj Aziz 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2024年第3期778-789,共12页
Confining stresses serve as a pivotal determinant in shaping the behavior of grouted rock bolts.Nonetheless,prior investigations have oversimplified the three-dimensional stress state,primarily assuming hydrostatic st... Confining stresses serve as a pivotal determinant in shaping the behavior of grouted rock bolts.Nonetheless,prior investigations have oversimplified the three-dimensional stress state,primarily assuming hydrostatic stress conditions.Under these conditions,it is assumed that the intermediate principal stress(σ_(2))equals the minimum principal stress(σ_(3)).This assumption overlooks the potential variations in magnitudes of in situ stress conditions along all three directions near an underground opening where a rock bolt is installed.In this study,a series of push tests was meticulously conducted under triaxial conditions.These tests involved applying non-uniform confining stresses(σ_(2)≠σ_(3))to cubic specimens,aiming to unveil the previously overlooked influence of intermediate principal stresses on the strength properties of rock bolts.The results show that as the confining stresses increase from zero to higher levels,the pre-failure behavior changes from linear to nonlinear forms,resulting in an increase in initial stiffness from 2.08 kN/mm to 32.51 kN/mm.The load-displacement curves further illuminate distinct post-failure behavior at elevated levels of confining stresses,characterized by enhanced stiffness.Notably,the peak load capacity ranged from 27.9 kN to 46.5 kN as confining stresses advanced from σ_(2)=σ_(3)=0 to σ_(2)=20 MPa and σ_(3)=10 MPa.Additionally,the outcomes highlight an influence of confining stress on the lateral deformation of samples.Lower levels of confinement prompt overall dilation in lateral deformation,while higher confinements maintain a state of shrinkage.Furthermore,diverse failure modes have been identified,intricately tied to the arrangement of confining stresses.Lower confinements tend to induce a splitting mode of failure,whereas higher loads bring about a shift towards a pure interfacial shear-off and shear-crushed failure mechanism. 展开更多
关键词 Rock bolts Bolt-grout interface Bond strength Push test Triaxial tests
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Development of multi-functional anchorage support dynamic-static coupling performance test system and its application
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作者 Qi Wang Shuo Xu +4 位作者 Bei Jiang Chong Zhang Zhe Sun Jingxuan Liu Cailin Jiao 《International Journal of Mining Science and Technology》 SCIE EI CAS CSCD 2024年第3期339-349,共11页
In underground engineering with complex conditions,the bolt(cable)anchorage support system is in an environment where static and dynamic stresses coexist,under the action of geological conditions such as high stresses... In underground engineering with complex conditions,the bolt(cable)anchorage support system is in an environment where static and dynamic stresses coexist,under the action of geological conditions such as high stresses and strong disturbances and construction conditions such as the application of high prestress.It is essential to study the support components performance under dynamic-static coupling conditions.Based on this,a multi-functional anchorage support dynamic-static coupling performance test system(MAC system)is developed,which can achieve 7 types of testing functions,including single component performance,anchored net performance,anchored rock performance and so on.The bolt and cable mechanical tests are conducted by MAC system under different prestress levels.The results showed that compared to the non-prestress condition,the impact resistance performance of prestressed bolts(cables)is significantly reduced.In the prestress range of 50–160 k N,the maximum reduction rate of impact energy resisted by different types of bolts is 53.9%–61.5%compared to non-prestress condition.In the prestress range of 150–300 k N,the impact energy resisted by high-strength cable is reduced by76.8%–84.6%compared to non-prestress condition.The MAC system achieves dynamic-static coupling performance test,which provide an effective means for the design of anchorage support system. 展开更多
关键词 Anchorage support system Development of test system Dynamic-static coupling test Combined stress
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Mechanical behaviour of fiber-reinforced grout in rock bolt reinforcement
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作者 Yingchun Li Ammar Ahmed Danqi Li 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2024年第2期437-453,共17页
Grouted rock bolts subject to axial loading in the field exhibit various failure modes,among which the most predominant one is the bolt-grout interface failure.Thus,mechanical characterization of the grout is essentia... Grouted rock bolts subject to axial loading in the field exhibit various failure modes,among which the most predominant one is the bolt-grout interface failure.Thus,mechanical characterization of the grout is essential for understanding its performance in ground support.To date,few studies have been conducted to characterize the mechanical behaviour of fiber-reinforced grout(FRG)in rock bolt reinforcement.Here we experimentally studied the mechanical behaviour of FRG under uniaxial compression,indirect tension,and direct shear loading conditions.We also conducted a series of pullout tests of rebar bolt encapsulated with different grouts including conventional cementitious grout and FRG.FRG was developed using 15%silica fume(SF)replacement of cement(by weight)and steel fiber to achieve highstrength and crack-resistance to overcome drawbacks of the conventional grout.Two types of steel fibers including straight and wavy steel fibers were further added to enhance the grout quality.The effect of fiber shape and fiber volume proportion on the grout mechanical properties were examined.Our experimental results showed that the addition of SF and steel fiber by 1.5%fiber volume proportion could lead to the highest compressive,tensile,and shear strengths of the grout.The minimum volume of fiber that could improve the mechanical properties of grout was found at 0.5%.The scanning electron microscopy(SEM)analysis demonstrated that steel fibers act as an excellent bridge to prevent the cracks from propagating at the interfacial region and hence to aid in maintaining the integrity of the cementitious grout.Our laboratory pullout tests further confirmed that FRG could prevent the cylindrical grout annulus from radial crack and hence improve the rebar’s load carrying capacity.Therefore,FRG has a potential to be utilized in civil and mining applications where high-strength and crack-resistance support is required. 展开更多
关键词 Fiber-reinforced grout(FRG) Steel fibers Mechanical properties Direct shear test Pullout test
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Research on aiming methods for small sample size shooting tests of two-dimensional trajectory correction fuse
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作者 Chen Liang Qiang Shen +4 位作者 Zilong Deng Hongyun Li Wenyang Pu Lingyun Tian Ziyang Lin 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2024年第3期506-517,共12页
The longitudinal dispersion of the projectile in shooting tests of two-dimensional trajectory corrections fused with fixed canards is extremely large that it sometimes exceeds the correction ability of the correction ... The longitudinal dispersion of the projectile in shooting tests of two-dimensional trajectory corrections fused with fixed canards is extremely large that it sometimes exceeds the correction ability of the correction fuse actuator.The impact point easily deviates from the target,and thus the correction result cannot be readily evaluated.However,the cost of shooting tests is considerably high to conduct many tests for data collection.To address this issue,this study proposes an aiming method for shooting tests based on small sample size.The proposed method uses the Bootstrap method to expand the test data;repeatedly iterates and corrects the position of the simulated theoretical impact points through an improved compatibility test method;and dynamically adjusts the weight of the prior distribution of simulation results based on Kullback-Leibler divergence,which to some extent avoids the real data being"submerged"by the simulation data and achieves the fusion Bayesian estimation of the dispersion center.The experimental results show that when the simulation accuracy is sufficiently high,the proposed method yields a smaller mean-square deviation in estimating the dispersion center and higher shooting accuracy than those of the three comparison methods,which is more conducive to reflecting the effect of the control algorithm and facilitating test personnel to iterate their proposed structures and algorithms.;in addition,this study provides a knowledge base for further comprehensive studies in the future. 展开更多
关键词 Two-dimensional trajectory correction fuse Small sample size test Compatibility test KL divergence Fusion bayesian estimation
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