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51.
T J Yang 《In vivo (Athens, Greece)》1987,1(5):297-302
Canine cyclic hematopoiesis (CH) was first described in Gray Collies as the lethal gray syndrome, and was subsequently shown to be a counterpart of human cyclic neutropenia (CN). The disease is characterized by a recurrent cyclic change in the levels of neutrophils and other blood elements at approximately 12-day intervals. It is caused by an autosomally recessive gene with pleiotropic effects or a CH gene which is closely linked to a gray color gene. The infectious insult on affected animals is periodic but its clinical and pathologic effects are continual and cumulative Affected dogs die after weaning and rarely survive over 6 months of age. There is evidence of immunoregulatory defects in these dogs. Reciprocal bone marrow transplantation indicates that the defect resides in the bone marrow, but the actual site and mechanism of the defect has not been established. The disease in Gray Collies represents a unique model system for studying the mechanism of cyclic hematopoiesis and hematopoietic regulation. Studies of the disease have made conceptual contributions toward understanding and treatment of human cyclic neutropenia. 相似文献
52.
①目的 了解猪同种原位心脏移植术后早期一氧化氮 (NO)、一氧化氮合酶 (NOS)含量的变化 ,及其与早期缺血再灌注损伤的关系。②方法 建立猪同种原位心脏移植模型。供心在移植前低温保存 (Thomas液 ,4℃ ) 4h ,移植成功心脏复搏后 2h取材。应用组织化学方法测定心肌组织中NO、NOS的含量 ,应用核酸原位末端标记法 (TUNEL)测定心肌细胞凋亡指数 ,作为评价心肌缺血再灌注损伤的指标。以正常心肌及单纯缺血心肌组织作为对照。③结果 移植后心肌组织NO、NOS的含量较缺血组与正常组低 ,差异有显著意义 (F =2 7.2 2 9、16 .2 0 3,q =5 .716~ 6 .4 12 ,P <0 .0 1)。移植组心肌细胞凋亡指数与正常组及缺血组比较明显升高 ,差异有显著性(F =16 3.884 ,q =7.4 82、6 .975 ,P <0 .0 1)。心肌组织NO、NOS含量与心肌细胞凋亡指数呈负相关关系 (r =- 0 .886、- 0 .795 ,P <0 .0 1)。④结论 猪心脏移植后早期心肌缺血再灌注损伤所致的细胞死亡主要表现为心肌细胞凋亡 ;再灌注期间内源性NO、NOS的减少参与了心脏移植后早期缺血再灌注损伤的发生 相似文献
53.
跟痛症的发病机制与临床诊断方法 总被引:10,自引:0,他引:10
跟痛症是一种临床常见多发疾病,以中老年患者居多,对于其发病机制与临床诊断鉴别方法不同的学者有着不同的见解。结合周福贻教授的理论与临床经验从发病机制、诊断、鉴别诊断及辅助检查等方面对跟痛症加以阐述。 相似文献
54.
55.
左双腔支气管导管管端位置与吸气峰压变化的关系 总被引:13,自引:3,他引:10
目的 观测无隆突钩双腔支气管导管(DLT)管端位置与吸气峰压(Ppeak)以及肺顺应性环形状改变的关系,探讨用Ppeak和顺应性环的变化评估DLT管端位置的可行性。方法 拟行右侧剖胸手术的成年患者32例,静脉诱导后插入左Mallinckrodt DLT,吸入氧化亚氮和地氟醚维持麻醉。按纤维支气管镜(FOB)确认DLT管端位置和通气方式将观测过程分为四个阶段:第一阶段(S1),管端位置正确的双肺通气;第二阶段(S2),管端位置正确的左侧单肺通气;第三阶段(S3),管端插入左下支气管(置管过深)的左侧单肺通气;第四阶段(S。),管端处在左支气管开口(置管偏浅)的左侧单肺通气。每阶段均机械通气15min。结果 回归方程预计插管深度与FOB检查符合者占71.9%。S2时Ppeak值比S1时增加50.8%,肺顺应性(Cdyn)值减少36.2%;S3时Ppeak值比S1时增加87.4%,Cdyn值减少56.8%。PV环曲线斜率向右明显移位,环体显著延长。结论 用无隆突钩DLT行肺隔离,在无FOB定位的条件时,联合应用听诊法、回归方程预计插管深度、动态监测气道峰压和P-V环的变化综合评估,可提高DLT管端的正确到位率。单肺通气的气道峰压超过双肺通气时的1.65倍,且气道峰压超过25cm H2O.应高度怀疑DLT管端发生过深移位。 相似文献
56.
关木通引起慢性间质性肾炎7例报告 总被引:3,自引:0,他引:3
目的 观察关木通所致慢性肾损伤的临床和病理改变特点。方法 本组 7例中 ,男 5例 ,女 2例。 3例服关木通汤药 ,4例服含关木通成药。分析服用时间、累积总量与肾损害首发症状及症状出现时间、肾功能和肾病理改变的关系。结果 汤药组 :服药时间平均 3 3 3个月 ,累积总量平均 82 9 3 g ,首发症状为乏力 3例 ,夜尿增多 2例 ,平均时间为 8 3个月 ,Cr平均 40 2 μmol/L。肾病理 :3例均为重度寡细胞性肾间质纤维化 ,肾小管广泛萎缩。成药组 :服药时间平均 7 5个月 ,累积总量平均 13 6g ,乏力 3例 ,夜尿增多 1例 ,恶心呕吐、头痛头晕 1例 ,平均18 8个月 ,Cr 3 62 8μmol/L。肾病理为重度寡细胞性间质纤维化和灶状纤维化各 2例 ,肾小管灶状萎缩 3例 ,广泛萎缩 1例。结论 汤药组关木通积累大 ,发病时间早 ,肾病理改变重。提示关木通所致肾损其临床表现、病理改变与服用关木通时间、剂量相关。 相似文献
57.
BACKGROUND AND PURPOSE: Health-related quality of life (HRQOL) is primarily an assessment of how domains of life are affected by health. This study investigated the factors influencing HRQOL of Taiwanese patients with bronchial asthma. METHODS: A cross-sectional study was conducted to assess the factors influencing HRQOL. The sample consisted of 242 outpatients with bronchial asthma. The Chinese language version of the St. George's Respiratory Questionnaire was used to measure HRQOL. Data were analyzed using simple regression and multiple regression. RESULTS: Age, marital status, level of education, asthma severity, peak expiratory flow, and previous hospital admissions were found to be predictors of HRQOL. Gender, duration of disease, and history of emergency visits were not correlated with HRQOL. The variables entered in the HRQOL model accounted for 17.4% of the total variance (adjusted R(2)). The regression coefficients indicated that the mean scores increased 7.68 in patients with moderate to severe disease severity, and increased 7.34 in patients with a history of hospital admissions. The mean scores decreased 7.60 in married patients. CONCLUSION: This study found that marital status, asthma severity, and history of hospital admissions were major predictors of HRQOL in Taiwanese patients with bronchial asthma. 相似文献
58.
59.
The measurement of amniotic fluid (AF) acetylcholinesterase isoenzyme (AChEI) is a relatively new method for early diagnosis of open neural tube defects (NTDs). As quantitative methods are of unproven reliability at present, the authors used a high resolving power qualitative method-vertical slab polyaerylamide gel electrophoresis. The benefits of this technique are: simplicity of operation, accuracy, unsophisticated equipment, and easily available reagents. Combined results of 9 NTDs studies revealed that samples from early pregnancy gave more accurate results than those from late pregnancy. 相似文献
60.
Effects of intermittent diethylstilbestrol diphosphate administration on the R3327 rat prostatic carcinoma 总被引:1,自引:0,他引:1
P Russo G Liguori W D Heston R Huryk C R Yang W R Fair W F Whitmore H W Herr 《Cancer research》1987,47(22):5967-5970
Clinical trials have utilized intermittent diethylstilbestrol diphosphate (DES) therapy in advanced symptomatic prostatic carcinoma to diminish the morbidity of standard endocrine therapy. To determine the effect of intermittent DES administration on the Dunning R3327 rat prostatic adenocarcinoma 60 days following tumor implant, 6 groups were randomly assigned: control (N = 8), castrate (N = 10), high dose DES (N = 8, 1.6 micrograms/ml DES continuously in drinking water), low dose DES (N = 10, 0.4 microgram/ml continuously in drinking water), intermittent high dose DES (N = 10, 1.6 micrograms/ml DES in drinking water for 1 week, then off for 3 weeks), and intermittent low dose DES (N = 10, 0.4 microgram/ml DES for 1 week, then off for 3 weeks). Results indicate that low or high dose DES, and intermittent low or intermittent high dose DES during the week of administration were able to reduce serum testosterone to castrate levels (0.1 ng/ml). After withdrawal of intermittent DES, serum testosterone returned toward control levels (1.0 ng/ml). Initial mean tumor burden between control and treatment groups was not significantly different. All DES exposed rats had a tumor volume at death (range, 15.6-18.3 cm3) smaller than control (mean, 25.4 cm3) or castrate (mean, 40.8 cm3) rats. Despite this significant survival advantage from the time of randomization was achieved only in castrate (median survival, 331 days) or high dose DES (median survival, 359 days) groups compared to control (median survival, 225 days). Similarly, significant prolongation in tumor doubling time was achieved only by rats receiving castration or high dose DES. Intermittent DES administration controls tumor volume but does not provide a survival advantage. In this respect, intermittent DES is inferior to castration. 相似文献