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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:6
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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:5
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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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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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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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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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Unbound^(28)O,the heaviest oxygen isotope observed:a cutting-edge probe for testing nuclear models 被引量:1
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作者 Jian-Guo Li Bai-Shan Hu +1 位作者 Shuang Zhang Fu-Rong Xu 《Nuclear Science and Techniques》 SCIE EI CAS CSCD 2024年第2期1-2,共2页
The beyond-dripline oxygen isotopes^(27,28)O were recently observed at RIKEN,and were found to be unbound decaying into^(24)O by emitting neutrons.The unbound feature of the heaviest oxygen isotope,^(28)O,provides an ... The beyond-dripline oxygen isotopes^(27,28)O were recently observed at RIKEN,and were found to be unbound decaying into^(24)O by emitting neutrons.The unbound feature of the heaviest oxygen isotope,^(28)O,provides an excellent test for stateof-the-art nuclear models.The atomic nucleus is a self-organized quantum manybody system comprising specific numbers of protons Z and neutrons N. 展开更多
关键词 TESTING QUANTUM system
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The evolution of cancer genomic medicine in Japan and the role of the National Cancer Center Japan 被引量:1
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作者 Teruhiko Yoshida Yasushi Yatabe +6 位作者 Ken Kato Genichiro Ishii Akinobu Hamada Hiroyuki Mano Kuniko Sunami Noboru Yamamoto Takashi Kohno 《Cancer Biology & Medicine》 SCIE CAS CSCD 2024年第1期29-44,共16页
The journey to implement cancer genomic medicine(CGM)in oncology practice began in the 1980s,which is considered the dawn of genetic and genomic cancer research.At the time,a variety of activating oncogenic alteration... The journey to implement cancer genomic medicine(CGM)in oncology practice began in the 1980s,which is considered the dawn of genetic and genomic cancer research.At the time,a variety of activating oncogenic alterations and their functional significance were unveiled in cancer cells,which led to the development of molecular targeted therapies in the 2000s and beyond.Although CGM is still a relatively new discipline and it is difficult to predict to what extent CGM will benefit the diverse pool of cancer patients,the National Cancer Center(NCC)of Japan has already contributed considerably to CGM advancement for the conquest of cancer.Looking back at these past achievements of the NCC,we predict that the future of CGM will involve the following:1)A biobank of paired cancerous and non-cancerous tissues and cells from various cancer types and stages will be developed.The quantity and quality of these samples will be compatible with omics analyses.All biobank samples will be linked to longitudinal clinical information.2)New technologies,such as whole-genome sequencing and artificial intelligence,will be introduced and new bioresources for functional and pharmacologic analyses(e.g.,a patient-derived xenograft library)will be systematically deployed.3)Fast and bidirectional translational research(bench-to-bedside and bedside-to-bench)performed by basic researchers and clinical investigators,preferably working alongside each other at the same institution,will be implemented;4)Close collaborations between academia,industry,regulatory bodies,and funding agencies will be established.5)There will be an investment in the other branch of CGM,personalized preventive medicine,based on the individual's genetic predisposition to cancer. 展开更多
关键词 Cancer genomic medicine BIOBANK patient-derived xenograft multi-gene panel test whole genome sequencing
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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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Why is early detection of colon cancer still not possible in 2023? 被引量:1
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作者 Valeria Tonini Manuel Zanni 《World Journal of Gastroenterology》 SCIE CAS 2024年第3期211-224,共14页
Colorectal cancer(CRC)screening is a fundamental tool in the prevention and early detection of one of the most prevalent and lethal cancers.Over the years,screening,particularly in those settings where it is well orga... Colorectal cancer(CRC)screening is a fundamental tool in the prevention and early detection of one of the most prevalent and lethal cancers.Over the years,screening,particularly in those settings where it is well organized,has succeeded in reducing the incidence of colon and rectal cancer and improving the prognosis related to them.Despite considerable advancements in screening technologies and strategies,the effectiveness of CRC screening programs remains less than optimal.This paper examined the multifaceted reasons behind the persistent lack of effect-iveness in CRC screening initiatives.Through a critical analysis of current methodologies,technological limitations,patient-related factors,and systemic challenges,we elucidated the complex interplay that hampers the successful reduction of CRC morbidity and mortality rates.While acknowledging the ad-vancements that have improved aspects of screening,we emphasized the necessity of addressing the identified barriers comprehensively.This study aimed to raise awareness of how important CRC screening is in reducing costs for this disease.Screening and early diagnosis are not only important in improving the prognosis of patients with CRC but can lead to an important reduction in the cost of treating a disease that is often diagnosed at an advanced stage.Spending more sooner can mean saving money later. 展开更多
关键词 Colorectal cancer Colorectal cancer screening Colorectal screening test Colon and rectal cancer
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Intermittent disturbance mechanical behavior and fractional deterioration mechanical model of rock under complex true triaxial stress paths 被引量:1
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作者 Zhi Zheng Hongyu Xu +3 位作者 Kai Zhang Guangliang Feng Qiang Zhang Yufei Zhao 《International Journal of Mining Science and Technology》 SCIE EI CAS CSCD 2024年第1期117-136,共20页
Mechanical excavation,blasting,adjacent rockburst and fracture slip that occur during mining excavation impose dynamic loads on the rock mass,leading to further fracture of damaged surrounding rock in three-dimensiona... Mechanical excavation,blasting,adjacent rockburst and fracture slip that occur during mining excavation impose dynamic loads on the rock mass,leading to further fracture of damaged surrounding rock in three-dimensional high-stress and even causing disasters.Therefore,a novel complex true triaxial static-dynamic combined loading method reflecting underground excavation damage and then frequent intermittent disturbance failure is proposed.True triaxial static compression and intermittent disturbance tests are carried out on monzogabbro.The effects of intermediate principal stress and amplitude on the strength characteristics,deformation characteristics,failure characteristics,and precursors of monzogabbro are analyzed,intermediate principal stress and amplitude increase monzogabbro strength and tensile fracture mechanism.Rapid increases in microseismic parameters during rock loading can be precursors for intermittent rock disturbance.Based on the experimental result,the new damage fractional elements and method with considering crack initiation stress and crack unstable stress as initiation and acceleration condition of intermittent disturbance irreversible deformation are proposed.A novel three-dimensional disturbance fractional deterioration model considering the intermediate principal stress effect and intermittent disturbance damage effect is established,and the model predicted results align well with the experimental results.The sensitivity of stress states and model parameters is further explored,and the intermittent disturbance behaviors at different f are predicted.This study provides valuable theoretical bases for the stability analysis of deep mining engineering under dynamic loads. 展开更多
关键词 True triaxial static and disturbance test Mechanical properties Failure mechanism and precursor Intermittent disturbance effect Fractional mechanical model
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Physical and mechanical properties and microstructures of submarine soils in the Yellow Sea 被引量:1
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作者 Zhuangcai Tian Yihua Chang +6 位作者 Sichao Chen Gengchen Wang Yanhong Hu Chuan Guo Lei Jia Lei Song Jianhua Yue 《Deep Underground Science and Engineering》 2024年第2期197-206,共10页
In recent years,the exploration of seabed has been intensified,but the submarine soils of silt and sand in the Yellow Sea area have not been well investigated so far.In this study,the physical and mechanical propertie... In recent years,the exploration of seabed has been intensified,but the submarine soils of silt and sand in the Yellow Sea area have not been well investigated so far.In this study,the physical and mechanical properties of silt and sand from the Yellow Sea were measured using a direct shear apparatus and their microstructures were observed using a scanning electron microscope.The test results suggest that the shear strength of silt and sand increases linearly with the increase of normal stress.Based on the direct shear test,the scanning electron microscope was used to observe the section surface of sand.It is observed that the section surface becomes rough,with many“V”‐shaped cracks.Many particles appear on the surface of the silt structure and tend to be disintegrated.The X‐ray diffraction experiment reveals that the sand and silt have different compositions.The shear strength of sand is slightly greater than that of silt under high stress,which is related to the shape of soil particles and the mineral composition.These results can be a reference for further study of other soils in the Yellow Sea;meanwhile,they can serve as soil parameters for the stability and durability analyses of offshore infrastructure construction. 展开更多
关键词 direct shear test MICROSCOPE physical properties submarine soil Yellow Sea
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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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Wolbachia-induced expression of kenny gene in testes affects male fertility in Drosophila melanogaster 被引量:2
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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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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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