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During the past 4 years, the performances of various tumor markers such as CA15-3, CEA, ferritin, beta 2-microglobulin and TPA have been evaluated in 78 cases of mammary cancer. The results were categorised according to differences in stages, difference in values from patients with recurrent tumors, the incidence of abnormal values and differences in values before and after surgery. When the incidence of values higher than the cutoff value was determined for each of stage I, II and III + IV, the rates for CEA were 14.3%, 4.9% and 27.8%, respectively, whereas those for TPA were 25.0%, 22.2% and 26.7%, respectively. In addition, for CA15-3, the incidences were 0% in stage I, 5.0% in stage II and 57.1% for combined stages III + IV. The average values for patients with recurrent tumors were 3.2 ng/ml CEA, 194.5 ng/ml ferritin, 316.2 U/l TPA and 81.3 U/ml CA15-3. The rates of abnormal values were 40.0% for CEA, 40.0% for ferritin, 85.7% for TPA and 63.6% for CA15-3. Differences in the values after surgical removal of the tumor were observed with these tumor markers: the CEA value was reduced from 1.6 +/- 1.4 to 1.1 +/- 0.5 (p less than 0.01) and the CA15-3 value from 12.2 +/- 8.4 to 9.3 +/- 4.1 (p less than 0.05), respectively, whereas that for ferritin was conversely increased from 48.9 +/- 48.0 to 74.0 +/- 70.0 (p less than 0.01). However, the values for TPA, despite showing a tendency to decrease, did not show any statistically significant alteration. The fluctuations of these marker levels in patients with recurrent tumors reflects the progress of the disease, with a sudden elevation in values indicating imminent death. The diagnostic significance of these markers is not high, but they are considered to be useful in detecting the progress or condition of a recurrent tumor.  相似文献   
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OBJECTIVE: The purpose of this study was to characterize the etching behavior of titanium in concentrated sulfuric acid and discuss its application on surface modification of titanium for biological use. METHODS: Commercially pure titanium (cpTi) plate was etched in 48% H2SO4 at RT -90 degrees C for 0.25-8 h. The weight loss was derived from the weight differences before and after etching. The surfaces after etching were characterized by surface roughness, X-ray diffractometry, and scannning electron spectroscopy. The apparent activation energy of the dissolution of cpTi into acid was derived from an Arrhenius plot of the rate of weight loss versus the acid temperature. RESULTS: The surface roughness of cpTi increased with the acid temperature and etching time. The surface roughness was strongly related to the weight loss. The weight loss increased drastically with the acid temperature after an initial period, which shortened with increasing acid temperature. The apparent activation energy for the dissolution of cpTi in H2SO4 was derived as 67.8 kJ/mol. SIGNIFICANCE: This study indicates that etching with concentrated sulfuric acid is an effective way to modify the surface of titanium for biological applications.  相似文献   
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微波干燥法对腊叶标本压制的实验研究   总被引:2,自引:1,他引:1  
目的:寻求一种不受气候条件影响而能成功制作腊叶标本的新技术。方法:采用微波干燥法,即用微波炉,由创制的直径31cm瓦楞纸板、吸水纸与玻璃皿组成的压制程序进行微波干燥。结果:微波干燥法可用于腊叶标本压制,且优于传统的常规腊叶标本压制方法。结论:本研究为腊叶标本的制作提供了一个新方法,收到了便捷、高效、且保色的理想效果。  相似文献   
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Electrostatic effects play an important role in protein interactions and may alter the biodistribution of antibodies. To study the effect of molecular charge on the biodistribution and infection imaging properties of human polyclonal immunoglobulin G (IgG), its iso electric point was varied by changing the level of diethylene triamine penta-acetic acid (DTPA) substitution: 0.8, 0.9, 3.7, 5.1 and 5.9 DTPA/IgG. Biodistributions of the different IgG preparations were determined at 10 min, 1, 6, 24, and 48 h post injection in normal rats, and infection imaging properties were determined in rats withEscherichia coli thigh infections. The biodistribution was significantly affected by pl. The immunoglobulin preparations with 0.9 and 3.7 DTPA/IgG showed faster clearance from the circulation and generally lower accumulation in most organs. The images had a target-to-background ratio of approximately 1.3–2.3:1. These results suggest that even though targeting is not affected by the level of DTPA substitutions, preparations with 0.9 and 3.7 DTPA/IgG may be superior imaging agents because of reduced accumulation by background organs.  相似文献   
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Alopecia areata universalis developed gradually over nine months in a 25-year-old woman. When her scalp hairs were totally lost and other body hair began to fall out, the symptoms of insulin dependent diabetes mellitus, an organ-specific autoimmune disease, developed rapidly and progressed to diabetic coma. Alopecia did not regress after the metabolic state improved following insulin therapy. Biopsy of the scalp skin revealed significant reduction of the total number of hair bulbs and prominent lymphocyte infiltration into the remaining hair follicles. Insulin dependent diabetes mellitus and alopecia areata universalis are both thought to be related to the autoimmune mechanism and sometimes coexist. However, simultaneous development of these two disorders is extremely rare.  相似文献   
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305例老年死亡病例医院感染回顾性调查   总被引:1,自引:0,他引:1  
本文结果表明,305例老年死亡病例医院感染的发病率为33.8%。感染最多部位为肺部(66.9%),其次为尿路感染(19.4%)。高龄患者,侵袭性操作、多种抗生素联合应用,激素疗法等是诱发医院感染的危险因素。58.8%的病原菌为革兰氏阴性杆菌,37.2%为真菌。31株病原菌药敏结果显示耐药率为33.3%。本文指出合理应用抗生素是预防医院感染的重要措施之一。  相似文献   
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