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OBJECTIVE To investigate the expression of Coxsackie and Adenovirus receptor (CAR) in renal-cell carcinoma and the relationship of the CAR to the biological behavior of the carcinomas.METHODS The immunohistochemical SP method was used to detect the expression of Coxsaekie and Adenovirus receptor in 48 cases of renalcell carcinoma and in 12 cases of normal renal tissue 2 cm away from the tumor tissue.RESULTS The positive rates of CAR were 100% in 12 cases of para-tumcr normal renal tissue and 35.4% in 48 cases of renal-cell carcinoma respectively. The difference of CAR expression between them was significant (P<0.05). The grades of the tumor were as follows: 22 in Grade Ⅰ, 17in Grade Ⅱ and 9 in Grade Ⅲ with the CAR positive rate being 54.5%,23.5% and 11.1%, respectively. There was a negative correlation between CAR expression and tumor grading (P<0.05). In addition, the number of the cases in stages Ⅰ to ⅣV were 19, 13, 11 and 5 respectively, with the respective positive rates being 57.9%, 30.8%, 18.2% and 0.0%, i.e. there also was a negative relationship between CAR expression and the stage (P<0.05).CONCLUSION CAR expression is down-regulated in renal-cell carcinoma compared with normal tissue. The level of CAR may be a sensitive predictor of differentiation, invasion and metastasis. Loss of CAR expression correlates with the invasive phenotype in our analysis of renal-cell carcinoma.  相似文献   
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PurposePlacental weight has been associated with mammographic pattern and coronary heart disease in the adult offspring, but the mechanisms are unknown. We evaluated the associations of maternal and cord blood hormones with placental weight in normal pregnancies.MethodsProspective study of 167 normal singleton pregnancies in Boston, USA and 256 in Shanghai, China. Maternal hormone levels at the 27th gestational week were available for all pregnancies. Cord blood measurements were available for 86 pregnancies in Boston and 104 in Shanghai. Pearson partial correlation coefficients of log-transformed hormone levels with placental weight were calculated.ResultsMaternal levels of estriol, testosterone, and progesterone (P < .05) were positively associated with placental weight. There was no such evidence for adiponectin, prolactin, and insulin-like growth factor (IGF)-I. Cord blood steroids tended to be inversely associated with placental weight, the results being statistically significant for testosterone (P < .05). There was a marginally significant positive association of cord blood IGF-I with placental weight. Reported results were adjusted for study center.ConclusionsPlacental weight appears to be positively correlated with maternal steroids. Its correlation with cord blood steroids, however, appears inverse, compatible with negative feedback mechanisms. There is also a suggestion for placental weight to be positively associated with cord blood IGF-I.  相似文献   
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Existing experimental data on pulmonary clearance of low-toxicity, poorly soluble particles in several mammalian species including the rat, mouse, guinea pig, dog, monkey, and human have been analyzed using a two-exponential time-decay function with one exponential representing the fast clearance phase and the other for the slow clearance phase. Mass fractions of both clearance phases and the corresponding clearance rates were determined from the lung burden data for different specific initial lung burdens (initial lung burden/ lung weight). It was found that the slow clearance mass fraction increased with lung burden for all species, and it approached almost 100% when the specific initial lung burden exceeded 1 mg/ g lung. However, the slow clearance mass fraction at low lung burdens was found to be much higher for the slow-clearing species (guinea pig, dog, monkey, and human) than for the fast-clearing species (rat and mouse). It was also found that the fast clearance rate was nearly a constant, but the slow clearance rate decreased with lung burden. In addition, both clearance rates differed slightly between the fast-clearing and slow-clearing species. Based upon these data, a formula is proposed to calculate the clearance rate at any lung burden for humans.  相似文献   
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Aging is the most important risk factor in cardiovascular disease (CVD), which is the leading causes of death worldwide and the second major cause of death in Taiwan. The major factor in heart failure during aging is heart remodeling, including long-term stress-induced cardiac hypertrophy and fibrosis. Exercise is good for aging heart health, but the impact of exercise training on aging is not defined. This study used 3-, 12- and 18-month-old rats and randomly divided each age group into no exercise training control groups (C3, A12 and A18) and moderate gentle swimming exercise training groups (E3, AE12 and AE18). The protocol of exercise training was swimming five times weekly with gradual increases from the first week from 20 to 60 min for 12 weeks. Analyses of protein from rat heart tissues and sections revealed cardiac inflammation, hypertrophy and fibrosis pathway increases in aged rat groups (A12 and A18), which were improved in exercise training groups (AE12 and AE18). There were no heart injuries in young rat hearts in exercise group E3. These data suggest that moderate swimming exercise training attenuated aging-induced cardiac inflammation, hypertrophy and fibrosis injuries of rat hearts.  相似文献   
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Most perianal abscesses originate from infected anal glands at the base of the anal crypts. Most abscesses below are usually drained through perianal incision and can be treated successfully. However, when perianal abscesses extend to the high intrapelvic cavity, it may be inadequate treatment through a single route incision through a perianal approach. The aim of this technical note is to show that combined anterior ilioinguinal and perianal incisions may provide optimal surgical field and multiple drainages. Here, we report a 56-year-old male patient with perianal-originating parapsoas abscesses. Residual abscess still remained after initial perianal incision and drainage after 1-month treatment. We presented combined anterior ilioinguinal and perianal incision technique methods for proper drainage in this complicated case. No recurrent or residual abscess remained after 2 weeks of operation. So, combined anterior ilioinguinal incision is feasible for high-located perianal abscess.  相似文献   
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