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Primary Non-Hodgkin’s Malignant Lymphoma of the Uterus at the Reference Hospital of Maradi/Niger: A Case Report
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作者 Moustapha Elhadji-Chefou Badé Malam-Abdou +5 位作者 Amadou Djibrilla-Almoustapha Maman Brah Moustapha Oumou Kimso Ibrahim Timi Liman Elhadji Ali Issa Abdou Amadou Borges Moreno Yuribet 《Open Journal of Blood Diseases》 2024年第2期43-46,共4页
Malignant non-Hodgkins lymphoma (MHNL) of the uterus is uncommon. We report a case diagnosed on the basis of histologic and immunohistochemical studies of a hysterectomy specimen induced by a very painful pelvic mass ... Malignant non-Hodgkins lymphoma (MHNL) of the uterus is uncommon. We report a case diagnosed on the basis of histologic and immunohistochemical studies of a hysterectomy specimen induced by a very painful pelvic mass in a 50-year-old patient with no previous history of the disease. It was classified as Ann Arbor IV Bb after imaging, given the medullary infiltration and signs of clinical and biological evolutivity: the patient had received two courses of chemotherapy, CHOP protocol. She died 23 days after the second treatment due to a hypertensive crisis. 展开更多
关键词 Malignant Non-Hodgkin’s Lymphoma uterus Referral Hospital Maradi/Niger
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Vaginal Cesarean Section, an Alternative to High-Risk Trigger on Scarred Uterus
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作者 Famakan Kane Mahamadou Keita +3 位作者 Yacouba Sylla Soumaila Diallo Diassana Mahamadou Traore Tidiane 《Open Journal of Obstetrics and Gynecology》 2024年第7期979-982,共4页
The objective is to report a clinical case of vaginal cesarean section performed to expel a dead fetus in scarred uterus. For this indication, vaginal hysterectomy constitutes an alternative to vaginal expulsion with ... The objective is to report a clinical case of vaginal cesarean section performed to expel a dead fetus in scarred uterus. For this indication, vaginal hysterectomy constitutes an alternative to vaginal expulsion with a high risk of uterine rupture and to classic abdominal cesarean section with risk of significant surgical trauma, particularly adhesions. However, this surgical technique, described since the 19th century, remains unknown to many practitioners and few publications exist on the subject throughout the world. Considered obsolete by some practitioners, it retains all its advantages in the practice of modern obstetrics. We report this case of expulsion of fetal death on a tri-scarred uterus performed by vaginal cesarean section at the Health District Reference Health Center (District Hospital) of Commune I in Bamako, Mali in a 37-year-old patient with a pregnancy of 27 weeks of amenorrhea. 展开更多
关键词 Vaginal Cesarean Section Birth on Scarred uterus In Utero Fetal Death
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Emergency C-Section on Multi-Scar Uterus: Maternal and Fetal Prognosis at the Nianankoro Fomba Hospital in Segou, Mali
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作者 Tidiani Traoré Seydou Traoré +21 位作者 Seydou Z. Dao Abdoul K. Ballo Kassoum Sidibé Brahima Donigolo Babou Traoré Famakan Kané Adama Coulibaly Abdrahamane Diarisso Alima Sidibé Adama Camara Yacouba Dembélé Thierno Boubacar Bagayoko Alpha Sanogo Adama Bah Abdoulaye Kassogue Hamidou Toungara Seydina Alioun Beye Agoustin Thera Youssou Traoré Ibrahima Teguété Niani Mounkoro Amadou Dolo 《Open Journal of Obstetrics and Gynecology》 CAS 2023年第5期997-1005,共9页
Background: Multi-scar uterus is a uterus with two or more scars due to surgery or trauma. Objective: The aim was to compare the maternal and fetal prognosis of emergency C-sections of bi-scar uteruses to those of ute... Background: Multi-scar uterus is a uterus with two or more scars due to surgery or trauma. Objective: The aim was to compare the maternal and fetal prognosis of emergency C-sections of bi-scar uteruses to those of uteruses with at least 3 scars at the Nianankoro Fomba Hospital in Segou. Materials and Methods: It was a descriptive and analytical cross-sectional study with prospective data collection over a 24-month period from March 20, 2018, to March 20, 2020. Results: In 2 years, we collected 103 emergency C-sections for multi-scar uterus out of 1198 C-sections with a frequency of 8.6%. The age group of 20 to 35 years was the most represented with 86.4%. The bi-scar uteruses were the most frequent with 77.7%. In 71.8% of cases, the C-section was performed during the latent phase of labor. The C-section was performed under loco-regional anesthesia in 89.3% of cases. Difficulties in hemostasis and bladder injury were the most frequent intraoperative accidents. Surgical site infection was the main postoperative complication. No maternal deaths were recorded. The perinatal prognosis was marked by 4.3% fresh stillbirths in bi-scar uterus against 3.7% in three or more scar uteruses and including 2 fresh stillbirths and 1 macerated. We did not record any early neonatal deaths after C-section. Conclusion: The frequency of emergency C-sections in patients with a multi-scar uterus remains very high in our hospital. A better awareness of the patients, their spouses and all the actors involved in the management of pregnancies and childbirth, can contribute to curb this trend. 展开更多
关键词 C-Section PROGNOSIS Segou Multi-Scar uterus EMERGENCY
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Associated Factors with Vaginal Delivery on a Uni- or Bi-Scar Uterus in a Low-Resource Setting
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作者 Kongwa Madoli Eloge Ilunga-Mbaya +5 位作者 Raha Maroyi Neema Nadine Omari Mukanga Denis Mukwege Nyakio Olivier Dieudonné Sengeyi Mushengezi Amani 《Open Journal of Obstetrics and Gynecology》 2023年第3期499-515,共17页
Introduction: Delivery in a scar uterus is one of the most debated topics in obstetrics. The objective was to determine the uterine test and the maternal-fetal outcome in patients with uni- and bi-scared uterus who re... Introduction: Delivery in a scar uterus is one of the most debated topics in obstetrics. The objective was to determine the uterine test and the maternal-fetal outcome in patients with uni- and bi-scared uterus who received the uterine test at Panzi General Referral Hospital. Methodology: This is a cross-sectional study with a prospective collection of patients who delivered on a uni- or bi-scareduterus at Panzi Hospital, between January 1, 2021 and August 1, 2022. Results: The average age of the patients was 27.09 years, with an age range of 25 - 34 years, they were mostly married (88.3%), with secondary educational level (60.4%). Pauciparous women, with a history of previous caesarean delivery once, represented respectively 52.2%;7.2% of parturients with an intergenital space equal to 18 months. 63.9% were overweight, 58.6% had undergone more than three ANC sessions. We noted statistically significant associations between modes of admission, water sac, type of membranes rupture, uterine height and success of uterine test (p 0.05). We did not find significant associations between parturient age, gestational age, intergestational interval, pregnancy term, surgical history, number of ANC performed, number of previous caesarean sections, number of newborns. We did not record any cases of maternal death but one case of perinatal death with 0.9% in this study. Conclusion: A good selection of patients with uni- or bi-scared uterus would allow the reduction of the fetomaternal morbidity during the uterine test. 展开更多
关键词 Uterine Test PROGNOSIS Uni- and Bi-Scared uterus Panzi Hospital
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Squamous cell carcinoma associated with endometriosis in the uterus and ovaries:A case report
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作者 Zhe Cai Gao-Liang Yang +4 位作者 Qing Li Lei Zeng Li-Xiang Li Yi-Pei Song Fan-Rong Liu 《World Journal of Clinical Cases》 SCIE 2023年第26期6240-6245,共6页
BACKGROUND Endometriosis is a common benign gynecological disease that causes dysmenorrhea in women of childbearing age.Malignant tumors derived from endometriosis are rarely reported and are found in only 1%of all pa... BACKGROUND Endometriosis is a common benign gynecological disease that causes dysmenorrhea in women of childbearing age.Malignant tumors derived from endometriosis are rarely reported and are found in only 1%of all patients with endometriosis.Here,we report a well-differentiated squamous cell carcinoma(SCC)caused by squamous metaplasia of endometriosis that co-occurred in the uterus and ovaries.CASE SUMMARY A 57-year-old postmenopausal woman had a 6-month history of irregular uterine bleeding.The uterus and adnexa were examined by computed tomography,and there were two solid cystic masses in the pelvis and right adnexa.Histological findings of surgical specimens showed well-differentiated SCC arising from squamous metaplasia of ectopic endometrial glands in the uterus and ovaries.The patient received chemotherapy after surgery and was followed up for 3 mo without metastasis.CONCLUSION The continuity between ectopic endometrial glands and SCC supports that SCC originates from ectopic endometrial glands with metaplasia towards squamous epithelium. 展开更多
关键词 Squamous cell carcinoma OVARIES uterus ENDOMETRIOSIS Case report
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Successful Reposition of an Incarcerated Gravid Uterus by Instrument:A Case Report and Literature Review
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作者 Jing Wang Jing-Ru Jiao +4 位作者 Ling-Chao Wang Ling-Ling Gong Hong-Li Wu Zhong-Yi Liu Su-Min Jiang 《Journal of Clinical and Nursing Research》 2023年第2期112-117,共6页
Incarcerated gravid uterus is a rare obstetric condition that contributes to pregnancy-related adverse outcomes,especially if the uterus remains incarcerated and the condition goes undiagnosed until delivery.An effect... Incarcerated gravid uterus is a rare obstetric condition that contributes to pregnancy-related adverse outcomes,especially if the uterus remains incarcerated and the condition goes undiagnosed until delivery.An effective diagnosis of this condition is benefited from pelvic examination combined with imaging methods and based on suspected symptoms.We present a case of ultrasound-assisted instrument reposition of an incarcerated gravid uterus at mid-gestation and discuss its clinical characteristics,diagnosis,imaging features,and treatment.We believe that once manual reduction fails,the use of instruments will undoubtedly be a better choice. 展开更多
关键词 PREGNANCY Incarcerated gravid uterus REPOSITION
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Changes in aortic endothelium ultrastructure in male rats following castration, replacement with testosterone and administration of 50α-reductase inhibitor 被引量:14
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作者 Ying-Li Lu Lin Kuang +5 位作者 Hui Zhu Hui Wu Xue-Fang Wang Yu-Ping Pang Ning-Jian Wang Dan-Lu Yu 《Asian Journal of Andrology》 SCIE CAS CSCD 2007年第6期843-847,共5页
Aim: To investigate the relationship between low androgen level and ultrastructure of vascular endothelium. Methods: Forty-eight male Sprague-Dawley rats were randomly divided into four groups: group A, normal rats... Aim: To investigate the relationship between low androgen level and ultrastructure of vascular endothelium. Methods: Forty-eight male Sprague-Dawley rats were randomly divided into four groups: group A, normal rats with sham castration; group B, castrated rats; group C, castrated rats given testosterone (T) undecanoate; and group D, intact rats treated with 5α-reductase inhibitor. After 10 weeks of treatment or castration, rats in different groups were killed and serum T, free T (FT) and dihydrotestosterone (DHT) were measured. The aortic endothelia were scanned under electron microcopy and the Vascular Endothelium Structure Score (VESS) was computed. Results: Serum T and FT concentrations of rats in group B were significantly lower than those of the other three groups (P 〈 0.01); DHT concentrations of group D rats were significantly decreased (P 〈 0.01 ) when compared with those of groups A and C. Rats in groups B and D rats (with low androgen levels) had obvious damage to their endothelial surfaces, which appeared crimpled, rough, adhesive and ruptured, and had high destruction of VESS. Conclusion: These results suggest that low concentrations of T and DHT are associated with ultrastructural damage of the aortic endothelia in male rats. 展开更多
关键词 ENDOTHELIUM ultrastructure TESTOSTERONE 5α-reductase inhibitor CASTRATION
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Effects of tachyplesin on the morphology and ultrastructure of human gastric carcinoma cell line BGC-823 被引量:19
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作者 Li QF Ou Yang GL +1 位作者 Li CY Hong SG 《World Journal of Gastroenterology》 SCIE CAS CSCD 2000年第5期676-680,共5页
AIM To investigate the morphological andultrastructural changes in the human gastriccarcinoma cell line BGC-823 after being treatedwith tachyplesin.METHODS Tachyplesin was isolated from acidextracts of Chinese horsesh... AIM To investigate the morphological andultrastructural changes in the human gastriccarcinoma cell line BGC-823 after being treatedwith tachyplesin.METHODS Tachyplesin was isolated from acidextracts of Chinese horseshoe crab(Tachypleustridentatus)hemocytes.BGC-823 cells and thecells treated with 2.0mg/L tachyplesin wereexamined respectively under light microscope,scanning and transmission electron microscope.RESULTS BGC-823 cells had undergone therestorational alteration in morphology andultrastructure after tachyplesin treatment.Thechanges were as follows:the shape of cells wasunanimous,the volume enlarged and cellsturned to be flat and spread,the nucleo-cytoplasmic ratio lessened and nuclear shapebecame rather regular,the number of nucleolusreduced and its volume lessened,heter-chromatin decreased while euchromatinincreased in nucleus.In the cytoplasm,mitochondria grew in number with consistentstructure relatively,Golgi complex turned to betypical and well-developed,rough endoplasmicreticulum increased and polyribosomedecreased.The microvilli at cellular surfacewere rare and the filopodia reduced whilelamellipodia increased at the cell edge.CONCLUSION Tachyplesin could alter themalignant morphological and ultrastructuralcharacteristics of human gastric carcinoma cellseffectively and have a certain inducing differen-tiation effect on human gastric carcinoma cells. 展开更多
关键词 STOMACH neoplasms/ultrastructure horseshoe CRABS STOMACH NEOPLASMS TACHYPLESIN microscopy electron cell MORPHOLOGY
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Effects of potassium deficiency on photosynthesis,chloroplast ultrastructure,ROS,and antioxidant activities in maize(Zea mays L.) 被引量:7
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作者 DU Qi ZHAO Xin-hua +5 位作者 XIA Le JIANG Chun-ji WANG Xiao-guang HAN Yi WANG Jing YU Hai-qiu 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2019年第2期395-406,共12页
Potassium(K)deficiency significantly decreases photosynthesis due to leaf chlorosis induced by accumulation of reactive oxygen species(ROS).But,the physiological mechanism for adjusting antioxidative defense system to... Potassium(K)deficiency significantly decreases photosynthesis due to leaf chlorosis induced by accumulation of reactive oxygen species(ROS).But,the physiological mechanism for adjusting antioxidative defense system to protect leaf function in maize(Zea mays L.)is unknown.In the present study,four maize inbred lines(K-tolerant,90-21-3 and 099;K-sensitive,D937 and 835)were used to analyze leaf photosynthesis,anatomical structure,chloroplast ultrastructure,ROS,and antioxidant activities.The results showed that the chlorophyll content,net photosynthetic rate(P_n),stomatal conductance(G_s),photochemical quenching(q_P),and electron transport rate of PSII(ETR)in 90-21-3 and 099 were higher than those in D937 and 835 under K deficiency treatment.Parameters of leaf anatomical structure in D937 that were significantly changed under K deficiency treatment include smaller thickness of leaf,lower epidermis cells,and vascular bundle area,whereas the vascular bundle area,xylem vessel number,and area in 90-21-3 were significantly larger or higher.D937 also had seriously damaged chloroplasts and PSII reaction centers along with increased superoxide anion(O_2^-·)and hydrogen peroxide(H_2O_2).Activities of antioxidants,like superoxide dismutase(SOD),catalase(CAT),and ascorbate peroxidase(APX),were significantly stimulated in 90-21-3 resulting in lower levels of O_2^-·and H_2O_2.These results indicated that the K-tolerant maize promoted antioxidant enzyme activities to maintain ROS homeostasis and suffered less oxidative damage on the photosynthetic apparatus,thereby maintaining regular photosynthesis under K deficiency stress. 展开更多
关键词 potassium deficiency MAIZE PHOTOSYNTHESIS CHLOROPLAST ultrastructure ROS and ANTIOXIDANT
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Ultrastructure of neuronal-like cells differentiated from adult adipose-derived stromal cells 被引量:16
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作者 Changqing Ye Xiaodong Yuan Hui Liu Yanan Cai 《Neural Regeneration Research》 SCIE CAS CSCD 2010年第19期1456-1463,共8页
β-mercaptoethanol induces in vitro adult adipose-derived stromal cells (ADSCs) to differentiate into neurons. However, the ultrastructural features of the differentiated neuronal-like cells remain unknown. In the p... β-mercaptoethanol induces in vitro adult adipose-derived stromal cells (ADSCs) to differentiate into neurons. However, the ultrastructural features of the differentiated neuronal-like cells remain unknown. In the present study, inverted phase contrast microscopy was utilized to observe β-mercaptoethanol-induced differentiation of neuronal-like cells from human ADSCs, and immunocytochemistry and real-time polymerase chain reaction were employed to detect expression of a neural stem cells marker (nestin), a neuronal marker (neuron-specific enolase), and a glial marker (glial fibrillary acidic protein). In addition, ultrastructure of neuronal-like cells was observed by transmission election microscopy. Results revealed highest expression rate of nestin and neuron-specific enolase at 3 and 5 hours following induced differentiation; cells in the 5-hour induction group exhibited a neuronal-specific structure, i.e., Nissl bodies. However, when induction solution was replaced by complete culture medium after 8-hour induction, the differentiated cells reverted to the fibroblast-like morphology from day 1. These results demonstrate that β-mercaptoethanol-induced ADSCs induced differentiation into neural stem cells, followed by morphology of neuronal-like cells. However, this differentiation state was not stable. 展开更多
关键词 human adipose-derived stromal cells β-mercaptoethanol induction in vitro differentiation ultrastructure neural stem cells neural regeneration
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Influence of lanthanum on chloroplast ultrastructure of soybean leaves under ultraviolet-B stress 被引量:8
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作者 彭倩 周青 《Journal of Rare Earths》 SCIE EI CAS CSCD 2009年第2期304-307,共4页
In order to investigate the effects of lanthanum(Ⅲ) on cell ultrastructure of soybean leaves under elevated ultraviolet-B irradiation (UV-B, 280-320 nm), the chloroplast ultrastructure of soybean seedlings was st... In order to investigate the effects of lanthanum(Ⅲ) on cell ultrastructure of soybean leaves under elevated ultraviolet-B irradiation (UV-B, 280-320 nm), the chloroplast ultrastructure of soybean seedlings was studied by hydroponics under laboratory conditions. The resuits showed that the thylakoid in chloroplast was orderly and clearly as soybean leaves were pretreated by La(Ⅲ). The thylakoid was indis- tinctly disordered, expanded and even indiscoverable in the chloroplast under UV-B stress. The impact on the thylakoid by the high intensity UV-B irradiation (T2) was bigger than that by the low intensity UV-B irradiation (T1). However, the destruction of the chloroplast structure caused by UV-B stress was alleviated by La(Ⅲ), and the arrangement of the thylakoid in the chloroplast became orderly and clearly. The effect of the alleviation by La(Ⅲ) under the low intensity UV-B irradiation (T1) was better than that under the high intensity UV-B irradiation (T2). 展开更多
关键词 LANTHANUM ultraviolet-B irradiation soybean leaves CHLOROPLAST ultrastructure rare earths
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Diffusion-weighted and diffusion-tensor imaging of normal and diseased uterus 被引量:9
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作者 Duygu Kara Bozkurt Murat Bozkurt +2 位作者 Mehmet Ali Nazli Ilhan Nahit Mutlu Ozgur Kilickesmez 《World Journal of Radiology》 CAS 2015年第7期149-156,共8页
Owing to technical advances and improvement of the software, diffusion weighted imaging and diffusion tensor imaging(DWI and DTI) greatly improved the diagnostic value of magnetic resonance imaging(MRI) of the pelvic ... Owing to technical advances and improvement of the software, diffusion weighted imaging and diffusion tensor imaging(DWI and DTI) greatly improved the diagnostic value of magnetic resonance imaging(MRI) of the pelvic region. These imaging sequences can exhibit important tissue contrast on the basis of random diffusion(Brownian motion) of water molecules in tissues. Quantitative measurements can be done with DWI and DTI by apparent diffusion coefficient(ADC) and fractional anisotropy(FA) values respectively. ADC and FA values may be changed by various physiological and pathological conditions providing additional information to conventional MRI. The quantitative DWI assists significantly in the differentiation of benign and malignant lesions. It can demonstrate the microstructural architecture and celluler density of the normal and diseased uterine zones. On the other hand, DWI and DTI are useful for monitoring the treatment outcome of the uterine lesions. In this review, we discussed advantages of DWI and DTI of the normal and diseased uterus. 展开更多
关键词 Magnetic resonance IMAGING DIFFUSION WEIGHTED IMAGING DIFFUSION TENSOR IMAGING uterus
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Ultrastructure of the sensilla on antennae and mouthparts of larval and adult Plutella xylostella (Lepidoptera:Plutellidae) 被引量:5
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作者 LI Yi-ping DU Xiao +2 位作者 LIU Fang-fang LI Yin LIU Tong-xian 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2018年第6期1409-1420,共12页
Plutella xylostella (L.) (Plutellidae) is an important agricultural pest throughout the world. In this study, the morphology of antennal and mouthpart sensilla in the larvae and adults of P. xylostella (L.) was ... Plutella xylostella (L.) (Plutellidae) is an important agricultural pest throughout the world. In this study, the morphology of antennal and mouthpart sensilla in the larvae and adults of P. xylostella (L.) was observed by using a scanning electron microscope. The larval antennae possess six sensilla basiconica, two sensilla chaetica and one sensillum styloconicum. Larval mouthparts possess six types of sensilla: sensilla chaetica, sensilla digitiformia, sensilla epipharyngeal, sensilla basiconica, sensilla styloconica and sensilla placodea. In the adult, seven types of sensilla are found on the antennae in males and six types of sensilla (sensilla basiconica absent) occur in females. Sexual dimorphism is also found in the number and size of these sensilla on the antennae of adults. We describe for the first time the five types of sensilla on the mouthparts of the adult of P. xylostella. This study provides useful information for further research into the function of these sensilla, and better understanding the behavioral mechanisms involved in pest control. 展开更多
关键词 Plutella xylostella antenna MOUTHPARTS SENSILLA ultrastructure
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Expression of neurocan mRNA and ultrastructure of brain tissue after cerebral ischemia and reperfusion in stroke-prone renovascular hypertensive rats treated by electroacupuncture 被引量:8
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作者 Feng Tan Saiying Wan +7 位作者 Haike Wu Qiwen HUO Jinliang Wang Wenlin Chen Meifeng Fang Xiaolin Liu Xuewen Wang Jingbo Sun 《Neural Regeneration Research》 SCIE CAS CSCD 2011年第36期2834-2838,共5页
We established a stroke-prone renovascular hypertensive rat model by bilateral constriction of the renal artery with sliver loop clips. After ten weeks, middle cerebral artery occlusion was induced for 2 hours. The ra... We established a stroke-prone renovascular hypertensive rat model by bilateral constriction of the renal artery with sliver loop clips. After ten weeks, middle cerebral artery occlusion was induced for 2 hours. The rats then received electro-acupuncture at Baihui (DU 20) and Dazhui (DU 14) after onset of ischemia for 30 days. In situ hybridization study showed that electroacupuncture significantly reduced the number of neurocan mRNA-positive cells in the ischemic penumbra and hippocampal tissues of rats. Electron microscopy results demonstrated that the structure of neurons and blood vessels in the ischemic tissues were restored with electroacupuncture. Overall, these data suggest that electroacupuncture may protect neurons against ischemic reperfusion injury in stroke-prone renovascular hypertensive rats, which may be regulated by downregulation of expression of nerve inhibitory factor neurocan mRNA. 展开更多
关键词 ELECTROACUPUNCTURE cerebral ischemia and reperfusion stroke-prone renovascular hypertensive neurocan mRNA cellular ultrastructure
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Scleral ultrastructure and biomechanical changes in rabbits after negative lens application 被引量:5
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作者 Xiao Lin Bing-Jie Wang +6 位作者 Yen-Chiao Wang Ren-Yuan Chu Jin-Hui Dai Xing-Tao Zhou Xiao-Mei Qu Hong Liu Hao Zhou 《International Journal of Ophthalmology(English edition)》 SCIE CAS 2018年第3期354-362,共9页
AIM: To address the microstructure and biomechanical changes of the sclera of rabbits after negative lens application by spectacle frame apparatus. METHODS: Five New Zealand rabbits of seven weeks post-natal were t... AIM: To address the microstructure and biomechanical changes of the sclera of rabbits after negative lens application by spectacle frame apparatus. METHODS: Five New Zealand rabbits of seven weeks post-natal were treated with -8 D lens monocularly over the course of two weeks. Refractive errors and axial length (AXI.) were measured at the 1st, 7th and 14th days of the induction period. Ultrastructure of sclera was determined with electron microscopy. Biomechanical properties were tested by an Instron 5565 universal testing machine. RESULTS: l.ens-induced (1.1) eyes elongated more rapidly compared with fellow eyes with AXI. values of 15.56±0.14 and 15.21±0.14 mm (P〈0.01). Fibril diameter was significantly smaller in the I.I eyes compared with control ones in the inner, middle, and outer layers (inner layer, 63.533 vs 76.467 nm; middle layer, 92.647 vs 123.984 nm; outer layer, 86.999 vs 134.257 nm, P〈0.01, respectively). In comparison with control eyes, macrophage-like cells that engulfed fibroblasts, dilated endoplasmic reticulum, and vacuoles in fibroblasts were observed in the inner and middle stroma in the/U eyes. Ultimate stress and Young's modulus were lower in the I.I eyes compared with those in the control eyes. CONCLUSION: Negative lens application alters eye growth, and results in axial elongation with changes in scleral ultrastructural and mechanical properties. 展开更多
关键词 negative lens rabbit biomechanics SCLERA ultrastructure
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Effect of Potassium on Ultrastructure of Maize Stalk Pith and Young Root and Their Relation to Stalk Rot Resistance 被引量:6
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作者 LI Wen-juan HE Ping JIN Ji-yun 《Agricultural Sciences in China》 CAS CSCD 2010年第10期1467-1474,共8页
To study the mechanism of potassium (K) application on improvement of maize resistance to stalk rot at cellular level, scanning electron microscope and transmission electron microscope were used to observe the effe... To study the mechanism of potassium (K) application on improvement of maize resistance to stalk rot at cellular level, scanning electron microscope and transmission electron microscope were used to observe the effect of K on the ultrastructure of maize stalk pith tissue and young root tip cell influenced by K and pathogen. In K deficient treatment, parenchyma cells of stalk pith had abnormal structure, and the cell wall between upper and lower adjacent cell was damaged, resulting in the loss of connections between vascular cells and insufficient supporting capacity. However, an improved K nutrition helped to keep a quite tight arrangement of root cell with thick cell wall, and prevent the invasion of pathogen effectively. Moreover, K treated root cell had abundant golgi apparatus, which could excrete large amount of secretions to degrade mycelium. Papillary and highly electronic intensity dot were accumulated at the invading point to prevent the deveJopment of the mycelium. Improved K nutrition could increase the resistant ability of maize plant to stalk rot, through keeping cell structure stability, preventing the expansion of intracellular space to reduce the chances of pathogen invasions, and through reinforcing cell wall and formation of intercellular and intracellular material to restrict further development of pathogen in host cell. 展开更多
关键词 potassium (K) maize stalk rot ultrastructure disease resistance
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Photosynthetic Characteristics and Ultrastructure of Chloroplast of Cucumber Under Low Light Density in Solar-Greenhouse 被引量:7
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作者 AIXi-zhen GUOYan-kui CHENLi-ping XINGYu-xian 《Agricultural Sciences in China》 CAS CSCD 2004年第2期129-135,共7页
The photosynthetic characteristics and ultrastructure of chloroplast of cucumber in solar-greenhouse were studied. The result showed that the photosynthetic rate (Pn), photosyntheticability (A350), carboxylation effic... The photosynthetic characteristics and ultrastructure of chloroplast of cucumber in solar-greenhouse were studied. The result showed that the photosynthetic rate (Pn), photosyntheticability (A350), carboxylation efficiency, light saturation point and light compensation pointall declined remarkably under low light density, indicating that the photosynthetic characteristicsof cucumber were closely related to light environment. Under low light density, the minimalfluorescence (Fo), alterable fluorescence (Fv), photochemical efficiency of PSⅡ(Fv/Fm), steadyfluorescence in light (Fs), maximal fluorescence (Fm) and actual efficiency of PSⅡ(φPSⅡ)etcincreased, indicating that the photochemical activity and efficiency for solar energy transformationenhanced, thus the light proportion used to electron transport also increased. The chlorophylla, b, a/b and carotenoid of shading leaves decreased. However, the depressed extent of Chl a andChl a/b were obviously larger than that of Chl b. The number of chloroplast and starch grainin cucumber leaves descended, but that of grana and lamella increased as a shaded result. Thesize of chloroplast and starch grain of shading leaves minished. 展开更多
关键词 CUCUMBER Low light density Photosynthetic characteristics ultrastructure of chloroplast
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Taxonomy and ultrastructure of five species of Tetraselmis (Prasinophyceae) isolated from China seas 被引量:3
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作者 Zhang Chengwu Hu Hongjun 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2002年第4期557-579,共23页
Comparative ultrastructural investigations on twenty-three isolates of Tetraselmis from the South China Sea, East China Sea and Huanghai Sea, have revealed that these isolates belong to:(1)Tetraselmis chui Butcher; (2... Comparative ultrastructural investigations on twenty-three isolates of Tetraselmis from the South China Sea, East China Sea and Huanghai Sea, have revealed that these isolates belong to:(1)Tetraselmis chui Butcher; (2)T. cordiformis (H. J. Carter) Stein; (3)T. helgolandica Kylin; (4)T. suecica (Kylin) Butcher; (5)T. guangdongensis sp. nov. Except T. helgolandica, the others are new records in China. T. guangdongensis sp. nov. is a new species. Its external and anatomical features closely resemble those of T. impellucida McLachlan et Parke. As in that species the pyrenoid is penetrated from many directions by cytoplasmic channels delimited by a double membrane. The protoplast withdraws from the apical portion of the theca, that portion which overlaid the trough inverts and pops out in the form of a teat. But unlike that species a starch sheath is present; pyrenoid matrix is surrounded by thylakoids which intervenes between the matrix and the starch sheath surrounding pyrenoid; the theca is stratified. 展开更多
关键词 TAXONOMY ultrastructure TETRASELMIS pyrenoid
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Cell Ultrastructure of Kiwifruit (Actinidia chinensis) Shoot Tips During Cryopreservation 被引量:3
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作者 XU Xiao-biao CAI Zi-guo +1 位作者 GU Qing-qing ZHANG Qiu-ming 《Agricultural Sciences in China》 CAS CSCD 2006年第8期587-590,共4页
The changes in the cell ultrastructure of in vitro cultured shoot tips from dwarf genotype of kiwifruit (Actinidia chinensis Ganmi 5) during cryopreservation were investigated. Shoot tips were preserved in liquid ni... The changes in the cell ultrastructure of in vitro cultured shoot tips from dwarf genotype of kiwifruit (Actinidia chinensis Ganmi 5) during cryopreservation were investigated. Shoot tips were preserved in liquid nitrogen using vitrification, and the cell ultrastructure was examined using transmission electron microscopy (TEM). The regular ultrastructure of the cell wall, cell membrane and nucleus of shoot tips could be damaged during the freezing and thawing associated with preservation using liquid nitrogen. The cell plasmolysis was increased and freezing tolerance was improved after precultufing and dehydrating in a preservation and vitrification solution (PVS2) (30% glycerol (Gly)+ 15% ethylene glycol (EG)+ 15% dimethylsulfoxide (DMSO) + 0.4 mol L^-1 sucrose). The structure of some cells with low degree of injury and reversible damage was similar to that of the control and they could undergo normal cell division and differentiation. Besides, they could recover automatically and regenerate after their reculture. 展开更多
关键词 CRYOPRESERVATION VITRIFICATION shoot tips ultrastructure KIWIFRUIT
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Effects of different LEDs light spectrum on the growth,leaf anatomy,and chloroplast ultrastructure of potato plantlets in vitro and minituber production after transplanting in the greenhouse 被引量:5
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作者 CHEN Li-li ZHANG Kai +5 位作者 GONG Xiao-chen WANG Hao-ying GAO You-hui WANG Xi-quan ZENG Zhao-hai HU Yue-gao 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2020年第1期108-119,共12页
Light spectrum plays an important role in regulating the growth and development of in vitro cultured potato(Solanum tuberosum L.) plantlets. The status of potato plantlets at the end of in vitro stage influences the m... Light spectrum plays an important role in regulating the growth and development of in vitro cultured potato(Solanum tuberosum L.) plantlets. The status of potato plantlets at the end of in vitro stage influences the minituber production after transplanting. With 100 μmol m^-2s^-1 total photosynthetic photon flux density(PPFD), a light spectrum study of 100% red light emitting diodes(LEDs) light spectrum(RR), 100% blue LEDs light spectrum(BB), 65% red+35% blue LEDs light spectrum(RB), and 45% red+35% blue+20% green LEDs light spectrum(RBG) providing illumination at the in vitro cultured stage of potato plantlets for 4 weeks using fluorescent lamp as control(CK) was performed to investigate the effects of LEDs light spectrum on the growth, leaf anatomy, and chloroplast ultrastructure of potato plantlets in vitro as well as the minituber yield after 2 months transplanting in the greenhouse. Compared to CK, RB and RBG promoted the growth of potato plantlets in vitro with increased stem diameter, plantlet fresh weight, plantlet dry weight, and health index. Furthermore, BB induced the greatest stem diameter as well as the highest health index in potato plantlets in vitro. Root activity, soluble protein, and free amino acid were also significantly enhanced by BB, whereas carbohydrates were improved by RR. In addition, thickness of leaf, palisade parenchyma and spongy parenchyma was significantly increased by BB and RBG. Chloroplasts under BB and RBG showed well-developed grana thylakoid and stroma thylakoid. Unexpectedly, distinct upper epidermis with greatest thickness was induced and palisade parenchyma and spongy parenchyma were arranged neatly in RR. After transplanting in the greenhouse for 2 months, potato plantlets in vitro from BB, RB, and RBG produced high percentage of large size tuber. BB improved fresh and dry weights of the biggest tuber but decreased tuber number per plantlet. In addition, RBG increased tuber number as well as tuber fresh and dry weight slightly. Our results suggested monochromatic blue LEDs as well as combined red, blue or/and green LEDs light spectrum were superior to fluorescent lamp spectrum in micro-propagation of potato plantlets. Therefore, the application of RBG was suitable;BB and RB could be used as alternatives. 展开更多
关键词 potato plantlets in vitro LEDs light spectrum leaf anatomy chloroplast ultrastructure minituber production
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