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141.
大鼠苍白球炎症反应后黑质铁代谢的改变   总被引:1,自引:0,他引:1  
目的:观察苍白球炎症对黑质铁代谢的影响及其对黑质多巴胺能神经元的毒性作用,探讨帕金森病与炎症反应的关系。方法:实验于2004-12/2006-05在首都医科大学北京神经科学研究所完成。选择健康SD雄性大鼠20只,随机数字表法分为生理盐水组和脂多糖组,每组10只。①脑立体定位注射生理盐水或脂多糖入大鼠双侧苍白球,分别于术前、术后7,14,21,28d观察大鼠行为学改变,采用动物行为轨迹分析软件计算平均运动速度及30min内运动距离。②用药4周后麻醉后处死大鼠(n=10,每组各5只),用免疫组织化学染色、Perl’s铁染色观察黑质游离铁及铁蛋白表达以及酪氨酸羟化酶阳性神经元、小胶质细胞变化。③另10只大鼠于用药后4周断头提取蛋白,采用高效液相色谱法定量统计分析纹状体多巴胺含量变化。结果:纳入动物20只,均进入结果分析。①两组大鼠行为学观察:脂多糖组大鼠术后7,14,21,28d的平均运动速度、30min内运动距离较术前呈进行性减少,生理盐水组大鼠运动指标无明显变化。脂多糖组动物术后14,21,28d平均运动速度和30min内运动距离低于生理盐水组,差异均有显著性意义[分别为(0.95±0.1),(1.65±0.10)cm/min;(0.75±0.08),(1.60±0.09)cm/min;(0.45±0.07),(1.73±0.07)cm/min;(1710±180),(2970±180)cm;(1350±144),(2880±156)cm;(1170±126),(3314±140)cm,P<0.05,0.01]。②脂多糖组大鼠苍白球、黑质小胶质细胞增生且呈现异常激活状态。黑质酪氨酸羟化酶阳性神经元低于生理盐水组[分别为(3002.0±362.1),(6079.0±510.2)个,P<0.01]。③脂多糖组大鼠黑质内铁蛋白及游离铁水平较生理盐水组明显增加。④大鼠纹状体多巴胺含量:脂多糖组纹状体多巴胺含量低于生理盐水组,差异有显著性意义[分别为(16.49±1.79),(22.79±1.56)nmol/g,P<0.05]。结论:苍白球的炎症导致黑质多巴胺能神经元的变性,黑质中游离铁和铁代谢相关蛋白的改变可能在这一过程中发挥重要作用。  相似文献   
142.
BACKGROUND: Several substitutes for intact, viable platelets have been used for transfusion, both to people and in animal models, with varied success. Infusible platelet membrane (IPM) is prepared from human platelets. IPM retains the glycoprotein (GP)lb receptor and has platelet factor 3 activity (procoagulant activity). However, factor V, serotonin, a cytoplasmic marker enzyme (purine nucleotide phosphorylase), GPIIb/IIIa complex, and HLA class I and II antigens are all absent in IPM. STUDY DESIGN AND METHODS: IPM is prepared from outdated platelets. The platelets were disrupted by freezing and thawing; they were washed and heated to inactivate possible viral contaminants, and then the sonicated membrane microvesicle fraction was separated and lyophilized. The hemostatic activity of IPM was measured by its ability to reduce the prolonged bleeding time in thrombocytopenic rabbits. RESULTS: Administration of IPM at a dose of 2 mg per kg results in a substantial reduction in the bleeding time. In a series of 23 experiments, a median preinjection bleeding time of 15 minutes was reduced to 6 minutes within 4 hours after IPM administration. Administration of IPM did show a mild enhancement in the thrombogenicity index, as measured in the Wessler rabbit model. This enhancement is, however, not significant, as a thrombogenicity index value of up to 0.6 is clinically acceptable. CONCLUSION: IPM may have clinical potential as a substitute for platelets in the treatment of bleeding due to thrombocytopenia.  相似文献   
143.
Although growth hormone (GH)‐ and prolactin (PRL)‐secreting pituitary adenomas are considered benign, in many patients, tumour growth and/or invasion constitute a particular challenge. In other tumours, progression relies in part on dysfunction of intercellular adhesion mediated by the large family of cadherins. In the present study, we have explored the contribution of cadherins in GH and PRL adenoma pathogenesis, and evaluated whether this class of adherence molecules was related to tumour invasiveness. We have first established, by quantitative polymerase chain reaction and immunohistochemistry, the expression profile of classical cadherins in the normal human pituitary gland. We show that the cadherin repertoire is restricted and cell‐type specific. Somatotrophs and lactotrophs express mainly E‐cadherin and cadherin 18, whereas N‐cadherin is present in the other endocrine cell types. This repertoire undergoes major differential modification in GH and PRL tumours: E‐cadherin is significantly reduced in invasive GH adenomas, and this loss is associated with a cytoplasmic relocalisation of cadherin 18 and catenins. In invasive prolactinomas, E‐cadherin distribution is altered and is accompanied by a mislocalisation of cadherin 18, β‐catenin and p120 catenin. Strikingly, de novo expression of N‐cadherin is present in a subset of adenomas and cells exhibit a mesenchymal phenotype exclusively in invasive tumours. Binary tree analysis, performed by combining the cadherin repertoire with the expression of a subset of known molecular markers, shows that cadherin/catenin complexes play a significant role in discrimination of tumour invasion.  相似文献   
144.
目的:调查兰州部队辖区黄河流域老年痴呆及认知障碍的患病率并分析其危险因素。方法:应用《长谷川智力量表》(22~30.5分为轻度异常,10.5~21.5分为痴呆前期,≤10分为痴呆期)和《临床记忆量表》(≤80分为异常),对黄河流域11个地区51个干休所16538人群中2944名60岁以上人员进行调查。采用挨家挨户一对一的的方法开展调查检测,只有2个量表评分均为异常才列为病例组,同时对一般情况、驻地海拔高度、家族遗传史、既往病史、生活习惯等5个方面30个危险因素进行调查,并应用SPSS10.0软件包将调查结果进行多元回归分析。结果:2944名受试者全部完成测试进入结果分析。①老年痴呆的患病率分别为痴呆0.71%,痴呆前期2.11%,轻度异常28.46%,总患病率为31.28%。②多元回归分析结果:脑萎缩(t=-6.304)、重大生活事件(t=-5.328)、高龄(t=-5.415)、无喝茶嗜好(t=-3.802)、脑梗死(t=-3.343)、女性(t=-2.604)、冠心病(t=2.496)、低文化程度(t=1.973)、职业(t=1.965)、高海拔地区(t=1.957)与老年痴呆相关(P均<0.05)。结论:①黄河流域老年痴呆及认知障碍发生与脑萎缩、重大生活事件、高龄、无喝茶嗜好、脑梗死、女性、冠心病、低文化程度、职业、高海拔地区等10种危险因素有关。②结果显示痴呆发病率较低,而痴呆前期及轻度异常发病率较高,所以应重视痴呆前期及轻度异常患者的干预治疗。  相似文献   
145.
Application of biosafety principles in blood establishments   总被引:1,自引:0,他引:1  
In light of increasing public and employee concern over potential infectious hazards associated with blood and other body fluids, several government agencies (the Food and Drug Administration, the Centers for Disease Control, the Occupational Safety and Health Administration, the Environmental Protection Agency, the Health Care Financing Administration and the National Heart, Lung and Blood Institute) cosponsored a Biosafety Workshop in April 1988. The objective of the workshop was to identify appropriate biosafety practices and standard control procedures to protect workers involved in the collection, storage, and transportation of human blood donations with the least possible disruption of the nation's blood supply. Speakers focused on human immunodeficiency virus (HIV) and hepatitis B virus (HBV); however, the safety principles discussed were considered equally applicable to other known (e.g., non-A, non-B hepatitis and human T-lymphotropic virus type I (HTLV-1) blood-transmitted infections. The resulting consensus included the need for blood establishments to develop and apply thoughtful biosafety programs to address staff training, accident prevention, HBV vaccination, handling spills, managing contaminated waste and transporting blood specimens. There was lack of agreement, however, on the usefulness of gloves during the phlebotomy of healthy blood donors.  相似文献   
146.

Purpose

Treatment of chronic mesh infections (CMI) after parietal repair is difficult and not standardized. Our objective was to present the results of a standardized surgical treatment including maximal infected mesh removal.

Methods

Patients who were referred to our center for chronic mesh infection were analyzed according to CMI risk factors, initial hernia prosthetic cure, CMI characteristics and treatments they received to achieve a cure.

Results

Thirty-four patients (mean age 54?±?13 years; range 23–72), were included. Initial prosthetic cure consisted of 26 incisional hernias and eight groin or umbilical hernias of which 21% were considered potentially contaminated because of three intestinal injuries, two stomas and two strangulated hernias. The mesh was synthetic in all cases. CMI appeared after a mean of 83 days (range 30–6740) and was characterized by chronic leaking in 52 cases (50%), an abscess in 22 cases (21%) and synchronous hernia recurrence in 17 cases (16.5%). Eighty-six reinterventions were necessary, including 36 mesh removals (42%), and 13 intestinal resections for entero-cutaneous fistula (15%). The CMI persistence rate was 81% (35 reinterventions out of 43) when mesh removal was voluntarily limited to infected and/or not incorporated material, but was 44% when mesh removal was voluntarily complete (19 reinterventions out of 43; p?<?0.001). On average, 3.4 interventions (1–11) were necessary to achieve a cure, after 2.8 years (0–6). Fourteen incisional hernia recurrences occurred (41%).

Conclusions

Treatment of chronic mesh infection is lengthy and resource-intensive, with a high risk of hernia recurrence. Maximal mesh removal is mandatory.
  相似文献   
147.
Summary— The organisation of a phase I unit must take into account the safety, quality and scientific requirements of such studies. The clinical pharmacology unit demands a highly qualified staff, as well as intensive care equipment. The investigator, generally a clinical pharmacologist who coordinates the different tasks as a project leader, has often to initiate a fruitful collaboration with a specialised consultant staff in order to implement the studies.  相似文献   
148.
Obesity is associated with various health consequences including infertility. In women, anovulation is most often linked to polycystic ovary syndrome or can be secondary to hypogonadotrophic hypogonadism. Hypogonadotrophic hypogonadism has also been described in men in several publications. More recent data suggest that obesity can induce direct spermatogenesis alteration. Bariatric surgery has become very popular in France in the last fifteen years. It is the most effective therapy in severe obesity and is associated with a significant and long-lasting weight loss and a significant decrease in obesity-related morbidity and mortality. More than 50,000 procedures are performed every year. Bariatric surgery has positive effects on menstrual cycles in women and on hypogonadism in men. But its effects on sperm parameters seem controversial. Furthermore, few data are available concerning the impact of bariatric surgery on assisted reproductive techniques (ART) outcomes.  相似文献   
149.
Summary— Recent clinical studies have reported a beneficial effect of fluoxetine, a serotonin reuptake inhibitor, in patients with severe refractory orthostatic hypotension. The present study was undertaken to investigate the effect of fluoxetine in orthostatic hypotension occurring during Parkinson's disease on both blood pressure values and number of clinical symptoms during orthostatic procedure evaluated using a validated clinical rating scale. In a pilot study performed in fourteen patients with idiopathic Parkinson's disease plus orthostatic hypotension, fluoxetine hydrochloride (20 mg orally daily during one month) significantly reduced the fall in systolic blood pressure [-33 ± 21 (SD) mmHg before fluoxetine vs -22 ± 19 mmHg after fluoxetine, P = 0.03] elicited by standing without modifying heart rate. The drug also significantly reduced the number of postural symptoms occurring during the orthostatic procedure [2.9 ± 1.5 (SD) before fluoxetine vs 1.2 ± 1.3 after fluoxetine, P = 0.006]. A similar pattern of response was obtained in an experimental model of neurogenic orthostatic hypotension obtained in chronically sino-aortic denervated dogs submitted to an 80° head-up tilt test procedure under chloralose anaesthesia. Fluoxetine did not change plasma noradrenaline levels. This pilot study suggests a slight but clinically significant effect of fluoxetine on both hemodynamic parameters and clinical symptoms in parkinsonian patients suffering from orthostatic hypotension.  相似文献   
150.
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