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51.
用免疫组织化学ABC法,研究了降钙素基因相关肽(CGRP)免疫反应神经纤维在大鼠胆总管末端与十二指肠连接处的分布。大鼠的胆总管末端有较丰富的CGRP免疫反应神经纤维,它们多呈串珠(膨体)状,少数为无膨体的细长纤维。CGRP-IR纤维主要分布肌层及血管周围,在神经纤维的附近可见到含CGRP-IR阳性颗粒的肥大细胞。本实验为神经免疫调节机制的研究提供了形态学依据。 相似文献
52.
John M. H. de Klerk Bernard A. Zonnenberg Alfred D. van het Schip Aalt van Dijk Shiuw H. Han Jacques M. S. R. Quirijnen Geert H. Blijham Peter R van Rijk 《European journal of nuclear medicine and molecular imaging》1994,21(10):1114-1120
Rhenium-186 hydroxyethylidene diphosphonate (186Re-HEDP) has been used for the palliative treatment of metastatic bone pain. A phase 1 dose escalation study was performed using 186Re-HEDP Twenty-four patients with hormone-resistant prostate cancer entered the study. Each patient had at least four bone metastases and adequate haematological function. Groups of at least three consecutive patients were treated with doses starting at 1295 MBq and increasing to 3515 MBq (escalated in increments of 555 MBq). Thrombocytopenia proved to be the dose-limiting toxicity, while leucopenia played a minor role. Early death occurred in one patient (10 days after administration) without clear relationship to the 186Re-HEDP therapy. Transient neurological dysfunction was seen in two cases. Two patients who received 3515 MBq 186Re-HEDP showed grade 3 toxicity (thrombocytes 25–50 × 109/1), defined as unacceptable toxicity. After treatment alkaline phosphatase levels showed a transient decrease in all patients (mean: 26% ± 10% IUA; range: 11%–44%). Prostate-specific antigen values showed a decline in eight patients, preceded by a temporary increase in three patients. From this study we conclude that the maximally tolerated dose of 186Re-HEDP is 2960 MBq. A placebo-controlled comparative study on the efficacy of 186Re-HEDP has been initiated. 相似文献
53.
Hospital discharge data from New Jersey were used to identify cases of asbestosis for the 8 years 1979-1986. Multiple admissions were deleted so that each individual was counted once at the time of his/her first hospitalization with an asbestosis diagnosis. White males had the highest age-adjusted average annual discharge rate of 19.3 cases/100,000 population, followed by black males (12.3 cases/100,000) and white females (1.2 cases/100,000). The discharge rate was positively associated with age in each race/sex category. The relationship between rates for black males and white males depended on age: under 65 years, the rates were almost equal, and at 65 years and older, the white rates were nearly twice the black rates. There were two areas of the state where the rates were highest: the north-central and southwest regions. These two areas represent manufacturing and shipbuilding applications of asbestos, respectively. During the years 1979-1986, the annual percentage increase in asbestosis rates was 20% for white males, 17% for black males, and 8% for white females. Continued surveillance will reveal when the rates for asbestosis stop increasing. 相似文献
54.
对食管癌高发区粮食中分离的互隔交链孢霉的毒素交链孢酚单甲醚(AME)在大鼠、小鼠体内的分布进行研究。给动物腹腔内注射氚标记的交链孢酚单甲醚(~3H-AME),然后在不同时间测各脏器的放射性。结果表明:在所测9个脏器中,2h肝脏含量最高,食管下段在大小鼠分别居第四和第三。但大小鼠分别在72、24h则以食管下段最高,说明AME及其代谢物在此清除较慢,即对其有较高的亲和力。 相似文献
55.
Effect of Population Aging on the International Organ Donation Rates and the Effectiveness of the Donation Process 总被引:2,自引:2,他引:0
N. Cuende J. I. Cuende J. Fajardo J. Huet M. Alonso 《American journal of transplantation》2007,7(6):1526-1535
This study analyzed the effect of population aging on organ donation for transplants in 43 countries and on the effectiveness of the donation process by comparing the results between Spain and the United States. The percentage of the population aged 65 or over accounted for 33% of the difference in the donation rates between the countries and for 91% of the variation in the rates after age adjustment. However, the level of aging of the Spanish (16.5%) and American (12.3%) populations failed to account for the percentages of deceased donors 65 or over (28% vs. 10%), due to the different age-specific donation rates, much higher in Spain above 50 years. These differences lead to a higher effectiveness of the process in the United States (3.1 transplanted organs per donor vs. 2.5 in Spain), though at lower rates of transplant per million population (73 vs. 87). We conclude that older populations have a greater donation potential as donation rates are strongly associated with population aging. It should therefore be mandatory to adjust donation rates for age before making comparisons. Additionally, effectiveness decreases with older donors, so age should be considered when establishing standards relating to organ donation and effectiveness of the process. 相似文献
56.
本文详细介绍了在新疆发现的花蠕形蚤、叶氏蠕形蚤、北山羊蠕形蚤、羊长喙蚤和狍长喙蚤的形态学特点、地理分布和某些生物学特性。 相似文献
57.
目的:评价低剂量容积数据高分辨率CT重组图像在肺部疾病中的应用价值。方法:对50例肺部疾病患者进行低剂量多层螺旋CT(MSCT)、高分辨率CT(HRCT)扫描及容积数据HRCT重组,比较所得到的低剂量容积数据HRCT重组图像和HRCT扫描图像质量并进行分级评分。结果:50例肺部疾病患者的低剂量容积数据HRCT重组图像和HRCT扫描图像质量相同,两者差异无统计学意义(P=0.188)。所见征象评分P值均>0.05,肺实变、网状影、蜂窝影、肺气肿、肺大泡得分趋向一致。低剂量MSCT扫描降低80%辐射量,缩短扫描时间。结论:低剂量容积数据HRCT重组图像评价肺部疾病的价值与HRCT扫描图像相同。低剂量容积数据HRCT重组大大降低辐射量,明显缩短检查时间,复检患者尤其适用,可以替代HRCT扫描。 相似文献
58.
大鼠直肠壁内淋巴管的微细分布和形态特征 总被引:4,自引:0,他引:4
目的观察大鼠直肠壁内淋巴管的分布和形态、结构特点,为探讨直肠癌淋巴道转移的机制,提供形态学依据。方法用半薄、超薄切片、光镜和电镜下观察大鼠淋巴管的微细分布。结果大鼠直肠壁的黏膜固有层深部可见毛细淋巴管,黏膜下层、肌层和浆膜层均有毛细淋巴管和淋巴管。结论直肠壁各层内均有毛细淋巴管,除黏膜层外,还存有淋巴管。 相似文献
59.
Zhen-yu Wu Laurent P. Rivory Michael S. Roberts 《Journal of pharmacokinetics and pharmacodynamics》1993,21(6):653-688
Distribution of Evans Blue (EB), sucrose, and water into the isolated perfused rat hindlimb was studied under various conditions using the multiple indicator dilution (MID) technique. Statistical moment analyses of the outflow profiles for the EB, sucrose, and water were used to define the vascular, extravascular, and total water spaces, respectively. The varied perfusion conditions included albumin content (2, 4.7, and 7%), temperature (25, 37, and 42 C), perfusate flow rate (2, 4, 8, and 12 ml/min) and the presence/absence of red blood cells. The range of studies undertaken were chosen to represent the variety of conditions used in the preparation of both isolated animal and human limbs, the latter being particularly important in cytotoxic therapy for recurrent malignant melanoma. The distribution volumes of EB, sucrose, and water were dependent on the flow rate and the albumin content of perfusate. The normalized variances (CV
2
) of the markers were of the following order: sucrose (2.18) > water (1.58) > EB (0.68), indicating that some disequilibrium occurs during the capillary exchange of water and sucrose. It is suggested that a Krebs-Henseleit buffer containing 2% BSA is a suitable perfusate for most studies of the isolated rat hindlimb perfusion. The effect of albumin concentration manifests itself only at higher flows.We acknowledge the support of the National Heart Foundation (Queensland) and the Mayne Bequest Foundation. This study was conducted while the investigator (Z.Y. Wu) was in receipt of a WHO Research Training Grant. Professor M. S. Roberts also acknowledges the support of the Queensland and Northern New South Wales Lions Kidney & Medical Research Foundation. 相似文献
60.
F. Lapicque D. Mainard P. Gillet E. Payan B. Bannwarth P. Netter 《European journal of clinical pharmacology》1996,50(4):283-287
Objective: In order to document the stereoselective distribution in joints of a chiral nonsteroidal anti-inflammatory drug, the relative
affinities of the enantiomers of tiaprofenic acid in synovium and for cartilage were compared.
Methods:
The distribution of tiaprofenic acid in synovium and in cartilage was studied 25 h after administering the racemic drug for
2 days (600 mg of a sustained-release preparation, once daily), in 12 inpatients with osteoarthritis of the hip requiring
arthroplasty. Enantiomers were quantified in plasma and freeze-ground tissues by a chiral HPLC assay.
Results:
Plasma concentrations of the dextrorotatory (R) enantiomer (0.40 μg/ml) were higher than those of its antipode. The concentration
of racemate in synovium (in dried and fresh tissues, 150% and 40%, respectively, of the concentration in plasma) was much
higher than that in cartilage (in dried tissues 32% of the plasma concentration). The ratio of the active, dextrorotatory
(R) enantiomer to its antipode was higher in synovial tissue than in plasma.
Conclusion:
Tiaprofenic acid is distributed stereoselectively in plasma and synovium, which contain a higher concentration of the active,
dextrorotatory (R) enantiomer. In cartilage, it reaches only a very low concentration.
Received: 26 June 1995/Accepted in revised form: 7 November 1995 相似文献