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51.
52.
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   
53.
目的:探讨股骨头缺血坏死的病理和影像学研究进展情况。方法:阅读并分析关于股骨头缺血坏死的文献。结果:影像学检查反映疾病的病理改变,在诊断中占有重要地位。结论:磁共振成像具有很高的敏感性和准确性,不仅能发现股骨头坏死的早期病变,且能反映病变的范围和程度,对早期诊断和治疗具有积极意义。  相似文献   
54.
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   
55.
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   
56.
Bulletin of Environmental Contamination and Toxicology -  相似文献   
57.
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   
58.
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   
59.
本文报告一种新的改良式远端脾肾静脉分流术,即脾静脉与左肾静脉侧侧吻合、脾静脉远端结扎,再将胃冠状静脉结扎。作者经治7例,初步观察疗效较好,术后无死亡,无复发出血,无肝性脑病发生。本文对这种手术的步骤和优点进行了讨论和分析。  相似文献   
60.
BACKGROUND AND PURPOSE: There are limited data on the pattern of cancer distribution among adolescents in Taiwan. This study evaluated the characteristics of these rare cancers in a medical center. METHODS: Analyses of the characteristics of malignant neoplasms for patients aged 14 to 17 years at diagnosis were performed for all cases recorded in the tumor registry of Chang Gung Memorial Hospital (CGMH) at Linkou for the period 1995 to 2001. All eligible tumors were categorized in 1 of 12 diagnostic groups according to the scheme of the International Classification of Childhood Cancer (ICCC). Relative frequencies, age, and gender variations and the characteristics of tumor types were analyzed. RESULTS: Cancer was diagnosed in 320 adolescents during the study period. The male/female ratio was 1.17. Leukemia was the leading diagnostic group. The frequency of carcinomas increased with age and was highest among 17-year-olds. In this age group, non-rhabdomyosarcoma soft tissue sarcoma/primitive neuroectodermal tumor (non-RMS STS/PNET), thyroid carcinoma (CA) and ovarian germ cell tumor (GCT) were the 3 most common solid tumors; the embryonal malignancies were rare. Tumors with the greatest male predominance were intracranial GCT (91%), nasopharyngeal CA (87.5%), osteosarcoma (84.6%), and colorectal CA (75%). Tumors with the greatest female predominance were thyroid CA (78.3%), gonadal GCT (75%), and non-RMS/PNET (56.5%). Hepatocellular CA comprised 9.4% of all carcinomas. CONCLUSIONS: The relative frequency and the distribution of histology subtypes among adolescents were between those of childhood and adult cancers. There were marked variations in tumor occurrence between genders and among different ages.  相似文献   
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