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61.
目的:测定妊高征患者血清睾酮水平并探讨其临床意义。方法:采用放射免疫分析法测定妊高征患者30例、正常孕妇20例血清及其新生儿脐血睾酮水平。结果:妊高征患者血清睾酮水平(0.153±0.078nmol/L)明显高于正常孕妇组(0.023±0.015nmol/L),有显著性差异(P<0.001)。妊高征组脐血睾酮水平(0.052±0.041nmol/L)低于正常孕妇组(0.119±0.059nmol/L),有显著性差异(P<0.05),两组睾酮水平与新生儿性别无关(P>0.05)。结论:孕妇血清睾酮在妊高征的病理生理中起调节或加强作用。 相似文献
62.
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
63.
Ikuo Konishi 《Medical Electron Microscopy》1994,27(3-4):271-274
The developmental relationship between granulosa and stromal cells in the fetal ovary was reviewed. The proliferation and
expression of basic fibroblast growth factor (bFGF) and luteinizing hormone receptor (LHR) of both the granulosa and theca
cells was examined in the adult ovary. Ovarian granulosa cell tumors were then studied under light and electron microscopy
and for immunohistochemical expression of bFGF and LHR. In the follicular development of the adult ovary, bFGF expression
in the granulosa cells was correlated with theca cell proliferation. In ovarian granulosa cell tumors, estrogen-producing
tumors showed a stratified or microfollicular pattern being accompanied by theca cells which had ultrastructural features
of steroid-production, and these tumor cells exhibited immunoreactivity for bFGF. In contrast, tumors with no apparent hormone-production
showed a solid or gyriform pattern without admixture of theca cells, and were negative for bFGF. LHR was expressed in both
types of tumor. Accordingly, bFGF may play an important role in association with the theca cell component in granulosa cell
tumors. 相似文献
64.
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
65.
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
66.
This paper reviews the literature on colorectal cancer from a sex and gender-based perspective. Colorectal cancer is a major cause of death in the developed world, with rates increasing in developing countries. Although described by some writers as an ‘equal opportunity’ disease, it presents more risk to men than women. Both biological, or sex-linked factors, and gender-linked factors play a part in the aetiology of the disease, while gender differences in the use of screening and treatment also help shape the mortality gap between women and men for this condition. Without an appreciation of the part played by sex and gender in the risk of colorectal cancer, and without a gender-sensitive approach to screening in particular, it is possible that the mortality gap between men and women for this condition will widen in the future. 相似文献
67.
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
68.
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
69.
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
70.
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