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1.
Objective To verify a novel hypothesis that it is the difference of proliferative ability between Hertwig's epithelial root sheath (HERS) and the neighboring mesenchyme that leads to fragmentation of HERS. Methods Developmental processes of rat mandibular first molars from postnatal (PN) 10 to 25 days were observed. HERS was traced by immunohistochemistry for keratin 14. The activity of proliferation was examined by immunohistochemistry and immunofluorescence for proliferating cell nuclear antigen (PCNA) at PN 10 and 25 days respectively. Results At PN 10, HERS grew to its maximum length and maintained integrity. Subsequently, along with tooth root elongation, HERS was gradually fragmented. Either at PN 10 or 25 days, there were more PNCA-positive cells in the neighboring mesenchyme than in the HERS. Conclusion During rat tooth root development, the neighboring mesenchyme possesses higher proliferative ability than HERS, which results in the fragmentation of HERS. 相似文献
2.
Lou Zhong-jin罗仲金 Wang Ling王玲 Liu Qing 刘庆Tian Guang-zhao田光兆 Hu Xiao-su胡孝素 Huang Guang-qi黄光琦Qian Fang钱方 Ran Rui-tu冉瑞图West China University of Medical Sciences ChengduHuang De-huai黄德淮Chengdu Fifth People''s Hospital Chengdu 《中华医学杂志(英文版)》1987,100(9):740-744
Comparative studies are made on the relative
percentages of amino acid content and LDH isozyme
by electrophoresis and Slab-PAGE in adult worms
of Ascaris lumbricoides, Ascaris suum and Toxocara
canis. The results show that there are remarkable
differences of Arg and His of 17 amino acids bet.
ween Toxocara canis and human intestinal ascaris,
human biliary ascaris and pig ascaris; there are also
obvious differences of band positions of LDH
isozyme electrophoretic patterns and band position
and amount of slab-PAGE patterns among them,
whereas no marked differences are found in these
three indices in human intestinal ascaris, human
biliary ascaris and pig ascaris. 相似文献
3.
Xiaofang Chen Yueji Sun Haiyan Liu Yunqiao Ding Shujuan Liu Jinghua Chen Xueying Wang Zhenpeng Han Fang Qu 《中国神经再生研究》2006,1(8):763-765
BACKGROUND: Cognitive impairment after stroke associates with various factors, such as age, educational years, etc. Besides concerning about the recovery of limb function after stroke, we should also focus on the rehabilitation of cognition. Moreover, we'd better pay attention to the control of all the risk factors of stroke, and improve the quality of life in stroke patients.
OBJECTIVE: To analyze the factors that affect cognitive impairment after stroke.
DESIGN: A related factors analysis.
SETTINGS: Department of Neurology of Dalian Port Hospital and Dalian Second People's Hospital.
PARTICIPANTS: Totally 148 stroke inpatients were selected from Department of Neurology, Dalian Port Hospital and Dalian Second People's Hospital from April 2004 to December 2005, including 100 males and 48 females, aging 45-75 years with an average age of (67±8) years; Their educational years ranged 2-10 years with an average of (6.1±3.7) years; The disease course ranged 15-30 days; All were right-handed. Inclusive criteria: All were accorded with the diagnostic standard set by the Fourth National Academic Meeting for Cerebrovascular Disease; Confirmed by CT or MRI; Informed consents were obtained from all the subjects.
METHODS: After the disease conditions were stable, the patients were assessed with Wechsler memory scale (WMS) and Wisconsin card sorting test (WCST). WMS included forward and backward recitation of numbers and short-term memory (verbal memory, visual recognition). The number of times for correct and wrong classifications in WCST and the time to complete the trail making tests A and B were recorded. The focal volume, area and layer were recorded at 24 hours after admission. The general data of the patients were recorded, including name, sex, age, educational years, history of hypertension, history of diabetes mellitus. Electroencepalograph (EEG) was examined to record the wave shape, blood lipids were detected, and the cognition related indexes were analyzed with the Pearson correlation analysis. The correlation between cognitive indexes after stroke and the influencing factors were analyzed with multiple linear regression analysis.
MAIN OUTCOME MEASURES: ① Correlation between cognitive indexes and imaging indexes; ② Influencing factors for cognitive indexes after stroke.
RESULTS: All the 148 stroke patients were involved in the analysis of results. ① Correlation between cognitive indexes and CT indexes: There were obvious negative correlations between numerical symbol and focal layer (r =-0.234, P < 0.05), as well as between verbal memory and the focal area and volume (r =-0.363, -0.279, P < 0.05); Trail making test A had obvious positive correlation with focal area and volume (r =0.256, 0.256, P < 0.05). Results of multiple linear regression analysis: Correct classification was correlated with triglyceride (partial wave and θ wave (partial regression coefficient=0.231-0.908, P < 0.05); Verbal memory was correlated with EEG α wave, focal volume, sex, educational years and diabetes mellitus (partial regression coefficient=0.219-1.017, P < 0.05-0.01). Visual recognition had correlation with educational years and hypertension (partial regression coefficient=0.326, -1.163, P < 0.01). Trail making tests A and B were correlated with focal volume (partial regression coefficient=4.680, -18.561, P < 0.05).
CONCLUSION: The factors that affect the cognitive function after stroke include sex, age, educational years, hypertension, diabetes mellitus, triglyceride, EEG wave shape, and the focal area, volume and layer 相似文献
4.
睫状体上皮瘤是较为少见的眼部肿瘤,不易被发现,只有经病理检查才能了解其内部结构、肿瘤的大小及对眼球的损害程度。我们遇到2例睫状体上皮瘤,均经病理证实,报告如下:1 病例报告 例1,丁某,男,4O岁。因右眼视力下降半年、伴眼痛,于1994年4月1日入院。全身检查未见异常。眼部检查:右眼视力眼前手动,无充血,角膜透明,前房深浅正常,房水清,虹膜纹理清,瞳孔圆,对光反应灵敏,晶体透明,玻璃体混浊。眼底检查:视网膜下方呈青灰色隆起,约+20D,遮盖视 相似文献
5.
With the development of interventional therapy, it is necessary for evaluating cerebral vessels to instruct treatment and determine prognosis of patients with ischemic stroke; however, correlation of distribution of infarction focus and clinical symptoms with degrees of cerebrovasoular stricture is still unclear.OBJECTIVE: To evaluate the characteristics of cerebral arterial stricture of patients with ischemic stroke with transcranial Doppler (TCD) and color duplex flow imaging (CDFI) and compare the correlation between distribution of cerebral infarction focus and clinical types with magnetic resonance imaging (MRI).DESIGN: Contrast observation.SETTING: Department of Neurology, the First Hospital of Jilin University.PARTICIPANTS: A total of 159 patients with ischemic stroke were selected from the Department of Neurology, the First Hospital of Jilin University from January to December 2005, including 106 males and 53 females aged from 27 to 88 years. Bases on diagnostic criteria of cerebrovascular disease established by Rao et al, clinical manifestations of all patients were evaluated with CT or nuclear magnetic resonance. All patients provided the confirmed consent.METHODS: The accepted patients received TCD and CDFI examination at 1 week after onset of ischemic stroke. Among them, 112 patients received cerebrovascular imaging examination simultaneously. MRI was used to check cerebral infarction focus and cerebrovascular stricture > 50% was regarded as the accepted vessels. In addition, DWI-T2 TCD (Germany) was used to check middle cerebral artery, and degrees of middle cerebral artery were classified into mild, moderate and severe stricture based on blood velocity (140 cm/s,180 cm/s). Stroke was classified based on characteristics of infarction focus and clinical symptoms showed with MRI and correlation with degrees of cerebrovascular stricture was analyzed simultaneously.MAIN OUTCOME MEASURES: Correlation between the characteristics of ischemic stroke and clinical symptoms checked with TCD and CDFI.RESULTS: A total of 159 patients with ischemic stroke were involved in the final analysis; in addition, 112 oases received cerebrovascular imaging examination simultaneously. ① MRI results of 159 patients with cerebral artery occlusive disease (CAOD): There were 131 patients (82.3%) with cerebral infarction, 40 (25.2%)with transient ischemic attack and 4 (2.5%) with subclavian steal syndrome (SSS). ② Infarction types with MRI examination: There were 33 patients (20.8%) with solitary cerebral infarction and 98 (61.6%) with multiple-cerebral infarction. ③ Results of TCD, CDFI, MRI angiography, CT angiography and digital subtraction angiography (DSA): Among 112 patients, 181 lesion sites (61 .8%) were located in cranium and 112 lesion sites were located out of cranium; especially, lesion site was mostly observed in stem of middle cerebral artery (31.2%) and watershed of basilar artery (7.2%) in cranium and the beginning site of internal carotid artery (21 .4%) out of cranium. ④ Correlation of vascular stricture checking with TCD, MRI and clinical diagnosis: On one hand, MRI and clinical diagnosis demonstrated that 68 patients had a watershed infarction; meanwhile,TCD examination indicated that there were 3 patients with mild vascular stricture, 24 with moderate vascular stricture and 36 with severe vascular stricture. On the other hand, among 68 patients with non-watershed infarction, there were 27 patient with mild vascular stricture, 26 with moderate vascular stricture and 15 with severe vascular stricture. There were significant differences (x2 =26.854, P =0.001 ). Clinical diagnosis indicated that 40 patients had transient ischemic attack and TCD examination demonstrated that there were 8 patient with mild vascular stricture, 12 with moderate vascular stricture and 20 with severe vascular stricture. There were significant differences as compared with 68 patients with watershed infarction (x2 =21.258, P =0.001). ⑤Correlation of vascular stricture checking with CDFI, MRI and clinical diagnosis: On one hand, among patients who were determined as watershed infarction with MRI and clinical diagnosis, CDFI examination indicated that there were 32 patients with mild vascular stricture at neck, 25 with moderate vascular stricture and 6 with severe vascular stricture. On the other hand, among patients with non-watershed infarction, there were 48 patient with mild vascular stricture, 18 with moderate vascular stricture and 2 with severe vascular stricture.There were significant differences (x2 =6.018, P =0.019). Among patients with transient ischemic attack checking with clinical diagnosis, there were 23 patient with mild vascular stricture, 9 with moderate vascular stricture and 8 with severe vascular stricture. There were no significant differences as compared with patients with non-watershed infarction (x2 =0.597, P=0.440).CONCLUSION: ① TCD and CDFI are effective marks to determine cerebral arterial stricture and hemodynamical changes. ② Infarction and transient ischemic attack at watershed are generally clinical phenotypes of CAOD patients and infarction at watershed is correlated with degrees of cerebrovascular stricture.③ TCD, MRI and clinical analysis of stroke types are significant for instructing treatment and evaluate prognosis. 相似文献
6.
报告1987-1995年,我院骨科采用游离腓肠神经移植术修复上肢神经缺损8例,共14条神经。经1-9年临床随访,功能恢复,优;2例,良;4例,可;1例,差;1例,优良率75%。本文结合文献复习讨论了游离神经移植术克服周围缺损的适应症,手术时机、方式及影响术后神经功能的主要原因。 相似文献
7.
Zheng-Hua ZHU Bai-Ren WANG Qing-Rong TAN Xiao-Li DUAN Fang KUANG Zhen XU Gong JU Institute of Neurosciences Department of Psychiatrics the Fourth Military Medical University X i’an China 《中国神经科学杂志》2006,(3)
1 Introduction Exposure to hostile stressors causes a series of coor- dinated responses in the body, such as alterations of neu- roendocrine secretion, immune reaction and behavioral manifestation to maintain homeostasis stability and sur-vival of the organisms. Stressors are divided into two main categories: physical, or systemic, and psychological, or emotional / processive. Each stressor might activate a spe- cific central pathway to induce a special neuroendocrine response, even cause stre… 相似文献
8.
目的介绍面部蜗轴的相关解剖及其在美容整形外科中的重要作用。方法应用计算机检索PUBMED和网络上的相关文献,并限定语言种类为英文。同时检索中国期刊全文数据库的相关文章。结果共检索到包括电子文献在内的英文文章210余篇,中文文章36篇,将符合标准的21篇文献纳入本文的参考文献。结论面部蜗轴是口周肌肉的止点,与鼻唇沟的形成、SMAS、面部表情的表达、发音和语言等关系密切,在美容整形外科中具有重要作用。 相似文献
9.
Weijiang Zhao Fang Yuan Guilin Li Zhongfang Shi Yun Cui Yazhuo Zhang Zhongcheng Wang 《中国神经再生研究》2007,2(5):276-280
BACKGROUND: During formation of prolactin neoplasia, how cells and its structure in adenohypophysis affect prolactin cells should be further studied. Intermediate lobe can be regarded as a driving region to release prolactin (PRL) and may promote formation of prolactin neoplasia in pituitary anterior lobe.
OBJECTIVE: To observe the effect of diethylstilbestrol (DES) on the expressions of μ and m-calpains in pituitary intermediate lobe of female Wistar rats.
DESIGN: Observational contrast animal study.
SETTING: Beijing Neurosurgical Institute.
MATERIALS: A total of 21 female Wistar rats, 3 weeks old weighing 70–80 g were housed with free access to tap water and standard pellet food. They were kept in a CL-grade condition, at (24±1)℃ and a humidity of (55±5)%, and with a 12 hours day-night cycle. Caprine anti-μ- and m-calpains antibodies were provided by Santa Cruz Biotechnology, CA, USA; rabbit-anti-PRL antibodies by Dako, Denmark; rabbit-anti-ACTH antibody by Boster Company, Wuhan.
METHODS: The experiment was carried out in Pathophysiological Department and Animal Laboratory, Beijing Neurosurgical Institute from August 2006 to January 2007. ① Rats were randomly divided into groups with 7 in each group, including vehicle control group, in which rats were injected intraperitoneally with sun-flower seed oil (1 mL/kg, twice a week) for 16 weeks; DES group, where animals were administered with DES (5 mg/kg, twice a week) for 16 weeks; DES + vehicle control group, in which DES was administered for 12 weeks at the same dose with those in DES group, and then was discontinued and replaced by sun-flower seed oil (1 mL/kg, twice a week) for the following 4 weeks. ② At 16 weeks later, pituitary tissue was dealt with HE staining and PRL immunohistochemical examination to observe evoke of tumor; meanwhile, immunohistochemical examination was used to observe expression of PRL of pituitary anterior lobe, expressions of μ- and m-calpains of pituitary intermediate lobe and distribution of adrenocorticotropin.
MAIN OUTCOME MEASURES: ① Expression of PRL of pituitary anterior lobe, expressions of μ- and m-calpains of pituitary intermediate lobe and distribution of adrenocorticotropin. ② Morphological observation of pituitary tissue.
RESULTS: All 21 rats were involved in the final analysis. ① Results of immunohistochemical examination: Morphological changes of neoplasia in DES group were strongly positive to PRL, and this suggested that formation of prolactin adenoma was observed in pituitary tissue. As compared with vehicle control group, expression of adrenoeorticotropic hormone (ACTH) was increased in both DES group and DES + vehicle control group. In addition, expressions of μ- and m-calpains in pituitary intermediate lobe were higher in DES group than that in vehicle control group. Otherwise, expressions of m-calpains in pituitary intermediate lobe was decreased in DES + vehicle control group, but expression of μ-calpains was still increased. ② Morphological observation of pituitary tissue: Gland tubes were orderly arranged in rats in vehicle control group. Anterior pituitary gland in rats of DES group demonstrated an apparent disappearance of gland tubes and a relatively large-scaled vasculature formation, namely the vascular lake lined by tightly arranged endothelial cells. Local integrated tumor cell arrangements were also detected. In addition, the border between the IL and the anterior lobe was locally blurred. The definite tumor-like changes in pituitary tissues were confirmed in 6 of 7 female Wistar rats in DES group, and one spontaneous occurrence of tumor formation was found in vehicle control group. In DES + vehicle control group, DES withdrawal led to the subtile emergence of gland tube cavity, although tumor-like cells still existed in 4 of 7 rats, suggesting occurrence of the tumor regression due to the withdrawal of DES.
CONCLUSION: A long-term application of DES can enhance the expressions of ubiquitours neutral cysteine protease in pituitary intermediate lobe and this suggests that both of them play a key role in release of hormone and formation of prolactin neoplasia through directly promoting PRL expression and release of neighboring pituitary intermediate lobe. 相似文献
10.
LIAN Fang was born in Rongcheng City Shandong Province in September .In December she received her bachelor''''s degree.She has been engaged in clinical practice scientific research teaching at the Department of Gynecology the Affiliated Hospital of Shandong University of Traditional Chinese Medicine.…… 《中国结合医学杂志》2007,13(3):231-232
LIAN Fang,was born in Rongcheng City,Shandong Province in September 1957. In December 1982,she received her bachelor's degree. She has been engaged in clinical practice,scientific research and teaching at the Department of Gynecology,the Affiliated Hospital of Shandong University of Traditional Chinese Medicine.During this period,she received her master's degree from the Department of Gynecology of Integrated Chinese and Western Medicine in Nanjing 相似文献