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The association between kidney function and cancer incidence is inconsistent among previous reports, and data on the Japanese population are lacking. It is unknown whether kidney function modifies the cancer risk of other factors. We aimed to evaluate the association of estimated glomerular filtration rate (eGFR) with cancer incidence and mortality in 55 242 participants (median age, 57 years; 55% women) from the Japan Multi-Institutional Collaborative Cohort Study. We also investigated differences in cancer risk factors between individuals with and without kidney dysfunction. During a median 9.3-year follow-up period, 4278 (7.7%) subjects developed cancer. Moderately low and high eGFRs were associated with higher cancer incidence; compared with eGFR of 60-74 ml/min/1.73 m2, the adjusted hazard ratios (HRs) (95% confidence intervals [CIs]) for eGFRs of ≥90, 75-89, 45-59, 30-44 and 10-29 ml/min/1.73 m2 were 1.18 (1.07-1.29), 1.09 (1.01-1.17), 0.93 (0.83-1.04), 1.36 (1.00-1.84) and 1.12 (0.55-2.26), respectively. High eGFR was associated with higher cancer mortality, while low eGFR was not; the adjusted subdistribution HRs (95% CIs) for eGFRs of ≥90 and 75-89 ml/min/1.73 m2 were 1.58 (1.29-1.94) and 1.27 (1.08-1.50), respectively. Subgroup analyses of participants with eGFRs ≥60 and <60 ml/min/1.73 m2 revealed elevated cancer risks of smoking and family history of cancer in those with eGFR <60 ml/min/1.73 m2, with significant interactions. Our findings suggest that the relationship between eGFR and cancer incidence was U-shaped. Only high eGFR was associated with cancer mortality. Kidney dysfunction enhanced cancer risk from smoking.  相似文献   
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Angiotensin II receptor blockers (ARBs) are widely used for the treatment of hypertension. It is believed that treatment with an ARB increases the level of plasma angiotensin II (Ang II) because of a lack of negative feedback on renin activity. However, Ichikawa (Hypertens Res 2001; 24: 641-646) reported that long-term treatment of hypertensive patients with olmesartan resulted in a reduction in plasma Ang II level, though the mechanism was not determined. It has been reported that angiotensin 1-7 (Ang-(1-7)) potentiates the effect of bradykinin and acts as an angiotensin-converting enzyme (ACE) inhibitor. It is known that ACE2, which was discovered as a novel ACE-related carboxypeptidase in 2000, hydrolyzes Ang I to Ang-(1-9) and also Ang II to Ang-(1-7). It has recently been reported that olmesartan increases plasma Ang-(1-7) through an increase in ACE2 expression in rats with myocardial infarction. We hypothesized that over-expression of ACE2 may be related to a reduction in Ang II level and the cardioprotective effect of olmesartan. Administration of 0.5 mg/kg/day of olmesartan for 4 weeks to 12-week-old stroke-prone spontaneously hypertensive rats (SHRSP) significantly reduced blood pressure and left ventricular weight compared to those in SHRSP given a vehicle. Co-administration of olmesartan and (D-Ala7)-Ang-(1-7), a selective Ang-(1-7) antagonist, partially inhibited the effect of olmesartan on blood pressure and left ventricular weight. Interestingly, co-administration of (D-Ala7)-Ang-(1-7) with olmesartan significantly increased the plasma Ang II level (453.2+/-113.8 pg/ml) compared to olmesartan alone (144.9+/-27.0 pg/ml, p<0.05). Moreover, olmesartan significantly increased the cardiac ACE2 expression level compared to that in Wistar Kyoto rats and SHRSP treated with a vehicle. Olmesartan significantly improved cardiovascular remodeling and cardiac nitrite/ nitrate content, but co-administration of olmesartan and (D-Ala7)-Ang-(1-7) partially reversed this anti-remodeling effect and the increase in nitrite/nitrate. These findings suggest that olmesartan may exhibit an ACE inhibitory action in addition to an Ang II receptor blocking action, prevent an increase in Ang II level, and protect cardiovascular remodeling through an increase in cardiac nitric oxide production and endogenous Ang-(1-7) via over-expression of ACE2.  相似文献   
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Laparoscopic cholecystectomy and time-course changes in renal function   总被引:13,自引:3,他引:10  
Background: Recently, the retraction method has been used to reduce intraabdominal pressure (IAP) during laparoscopic surgery. The purpose of this study was to determine the serial changes in renal function during laparoscopic cholecystectomy (LC) using the retraction method. Methods: Urine output, effective renal plasma flow (ERPF), and glomerular filtration rate (GFR) were measured serially in seven patients who underwent LC with 12 mmHg pneumoperitoneum (High-IAP group) and five who underwent LC using the retraction method with 4 mmHg pneumoperitoneum (Low-IAP group). Results: Urine output, ERPF, and GFR were decreased during pneumoperitoneum in the High-IAP group, whereas no significant changes in any of these parameters were observed in the Low-IAP group. Conclusions: Our findings demonstrate that reduction of IAP to 4 mmHg using the retraction method prevents the transient renal dysfunction caused by prolonged 12 mmHg pneumoperitoneum during LC, suggesting that the retraction method reduces the risk of perioperative renal dysfunction during laparoscopic surgery. Received: 26 March 1996/Accepted: 27 July 1996  相似文献   
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1. The relationship between work-rate and the antihypertensive effect of exercise in hypertensives, and the mechanism of that effect, were investigated by a crossover clinical trial. 2. Ten mild hypertensives were randomly divided into two groups. One group performed low work-rate exercise (LWE) on a cycle ergometer for 10 weeks (blood lactate threshold; ~50% of maximum oxygen consumption [V?O2max]). After a 10 week interval without exercise training, these subjects were then switched to a high work-rate exercise (HWE) regimen (4 mmol/ L of blood lactate; ~75% of V?O2max) for another 10 weeks. In the other group, the order of exercise training was reversed. Since two patients withdrew from the protocol during HWE periods, statistical analysis was performed on the data from the remaining eight patients. There were no order effects observed in any of the data from the two groups. 3. During both LWE and HWE, resting blood pressure (BP) fell significantly after the initiation of exercise therapy (P<0.05). Furthermore, the overall effects of 10 weeks of LWE and HWE on BP were not significantly different. 4. The work-rate at the lactate threshold, which reflects physical fitness, had increased significantly by 16 W (P<0.01) after the LWE period and by 11 W (P<0.01) after the HWE. 5. During the LWE period, changes in haemodynamic and humoral variables were not significant, except for a reduction in plasma norepinephrine at week 10 (P<0.05). In the HWE period, changes in haemodynamic and humoral variables were not significant. 6. Based on these findings, LWE is recommended for mild hypertensives because of its safety.  相似文献   
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A case of cystadenocarcinoma of the liver is reported. The patient was a 73-year-old woman in whom a tumor was detected in the lateral segment of the liver during a health examination. Ultrasonograms and computed tomograms showed a multilocular cystic mass. Magnetic resonance imaging (MRI) showed a multilocular lowintensity mass, including a high-intensity portion and a portal branch compressed by the tumor. MRI with gadolinium showed an enhanced cyst wall. The cystic part of the tumor became smaller and the solid part became larger over a 1-month period, indicating that the tumor was malignant. Subsegmentectomy (S3) was performed and cystadenocarcinoma with cystadenoma was diagnosed by histopathological examination. Identification of changes in the appearance of a tumor should be helpful for the differential diagnosis of cystadenoma and cystadenocarcinoma.  相似文献   
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