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1.
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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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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I briefly review spheroids observed in the anterior horns of the spinal cord in amyotrophic lateral sclerosis (ALS). Spheroids are argentophilic bodies more than 20 μm in diameter. Recently, some connections between the proximal axonal swellings including spheroids and the perikarya have been reported in some ALS patients with a short clinical course or mild depletion of anterior horn neurons. Most of the cell bodies directly connected with the axonal swellings appear normal, and spheroids are considered to be one of the hallmarks of the early histological changes in this disorder. Spheroids are strongly positive with anti-phosphorylated neurofilament antibody, and are also positive with calcitonin gene-related peptide and anti-peripherin antibody. Some spheroids are immunostained with anti-synaptophysin antibody and anti-ubiquitin antibody. Spheroids are not immunostained with anti-phosphorylated tau antibody, or high molecular weight microtubule associated proteins. Electron microscopically, spheroids are usually composed of densely packed accumulation of 10 nm neurofilaments with a variety of orientations, plus vesicles, dense bodies and mitochondria. When the swellings of the initial segment is relatively pronounced, the undercoating is obscured and the neurofilaments become interwoven in some parts. In the first internode of the myelinated axons, as the swellings become larger, the neurofilaments lose their parallel orientation and become intermingled. Large accumulation of neurofilaments resembling spheroids in the perikarya of large anterior horn cells suggests that spheroids could be derived not only from the axon including the proximal portion, but also from the perikarya. Structures apparently identical to axonal spheroids are observed at the light and electron microscopic levels in the proximal portion of axons of anterior horn cells in animal models intoxicated with β, β'-iminodipropionitrile (IDPN), or with aluminum, in hereditary canine spinal muscular atrophy (HCSMA). The pathogenetic mechanism is probably associated with an impairment in slow axonal transport which particularly affects the neurofilaments in IDPN and aluminum intoxication. Impairment of slow axonal transport of neurofilaments also plays an important role in the pathogenesis of ALS. The average diameter of even normalappearing initial segment is larger in ALS than in the controls. The perikarya connected with the swollen proximal axons and their dendrites almost always appear normal. These findings suggest that the slow axonal transport of neurofilaments is probably impaired in this portion of the axon at an early stage in ALS as well as animal models for human ALS. However, techniques to analyze slow axonal transport in humans still remain tobe developed. Recently, overexpression of neurofilament subunits in transgenic mice produces a condition resembling ALS. The transgenic model may offer an interesting perspective not only for testing therapeutic strategies but also for investigating in a systematic way the various genetic and environment factors controlling the onset and progression of the disease and might yield new insights on the etiology of ALS.  相似文献   
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The effects of neurotransmitters or drugs on the release of endogenous dopamine (DA) and extracellular levels of its metabolites, 3,4-dihydroxyphenylacetic acid (DOPAC) and homovanillic acid (HVA), were examined in vivo by intracerebral dialysis. A dialysis tube was implanted stereotaxically through bilateral caudate nuclei of rats and perfused with the Ringer solution. Amounts of DA, DOPAC and HVA in the perfusates were measured by high performance liquid chromatography (HPLC) with electrochemical detection. The basal level of DA was 2.76 +/- 0.64 pg/min, whereas the levels of DOPAC and HVA were 218.7 +/- 20.7 and 142.4 +/- 10.6 pg/min, respectively. Apomorphine (4 mg/kg, i.v.) reduced the efflux of DA and its metabolites. Haloperidol (0.4 mg/kg, i.v.) did not change DA release and produced only a minor increase of its metabolites. This increase of metabolites was inhibited by pargyline. Met-enkephalin (10(-4) M), substance P (10(-4) M) and acetylcholine chloride (10(-4) M) added to the perfusing medium increased the release of DA. Met-enkephalin also increased the release of DOPAC. gamma-Amino-n-butyric acid (GABA, 10(-4) M) reduced the release of DOPAC and HVA when added to the perfusing medium. Thyrotropin releasing hormone (TRH, 5 mg/kg, i.v.) increased the release of HVA. These findings indicated that different mechanisms mediated effects of neurotransmitters or drugs on the release and metabolism of DA in the rat striatum.  相似文献   
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OBJECTIVES: Lateral biopsies are thought to have a better cancer detection rate compared with standard sextant biopsies. This study aimed to determine whether lateral peripheral zone biopsies in Japanese men who underwent transrectal ultrasound-guided prostate biopsies provided a significantly higher cancer detection rate than sextant biopsies. METHODS: Between 1999 and 2004, data were collected from 461 men who underwent prostate biopsy and had enough data regarding the performance of lateral biopsies for statistical analysis. There were two categories in this study: (i) patients who underwent sextant prostate biopsies; and (ii) patients who underwent sextant biopsies plus lateral biopsies. RESULTS: Prostate cancer was detected in 141 (30.6%) of 461 patients. It was detected in 24 (22.2%) of 108 patients who underwent sextant biopsies and 117 (33.1%) of 353 patients who underwent sextant plus lateral biopsies. Lateral biopsies were not associated with a statistically higher rate of positive biopsy findings; however, we found a significantly higher ratio of patients with positive findings in those with prostate specific antigen (PSA) levels 10 ng/mL (one of 71, 1.4%) among those who had positive cores only in lateral biopsy samples (P < 0.0001). CONCLUSIONS: Lateral biopsies did not show a significantly higher detection ratio of prostate cancer compared to sextant biopsies. However, lateral biopsies were more effective than sextant biopsies in patients with lower PSA levels. Our findings might be useful for the establishment of biopsy strategies to detect prostate cancer, especially in patients with lower PSA levels.  相似文献   
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We have treated advanced transitional-cell carcinoma of the urothelial tract with methotrexate, vinblastine, Adriamycin, and cisplatin (M-VAC) chemotherapy since July of 1985. We analyzed the effect of that chemotherapy in 26 patients with advanced urothelial cancer who were treated in our hospital and followed up. They were divided into two groups. Group 1 consisted of 15 patients with distant metastases. In all, 11 of them received M-VAC as adjuvant chemotherapy for metastatic lesions after surgical removal of the primary lesion, and the remaining 4 patients were not operable since they had very advanced-stage tumors; they received only M-VAC chemotherapy. Group 2 contained 11 patients who received M-VAC neo-adjuvant chemotherapy. In group 1, the overall response rate was 57.1% and the mean duration of response was 12.6 months. In the 11 patients who had received M-VAC as adjuvant therapy after surgical removal of the primary tumor, the mean duration of response was 14.1 months. After M-VAC chemotherapy, six patients underwent surgical resection of metastatic lesions and restaging was done pathologically in these cases. The clinical response coincided with the pathological response in all six cases. In group 2,5 of 11 patients experienced histological downstaging of the resected bladder. M-VAC chemotherapy combined with surgical resection of residual tumors has proved to be an effective option against advanced urothelial cancer.Presented at the 4th International Conference on Treatment of Urinary Tract Tumors with Adriamycin/Farmorubicin, 16–17 November 1990, Osaka, Japan  相似文献   
9.
beta 2-Microglobulin (beta 2-MG)-related amyloidosis has been reported as a complication in long-term hemodialysis patients. We observed beta 2-MG amyloid deposits in synovial sheaths, bone cysts and gastric mucosa. They showed unique ultrastructural features, that is bundles or nodules consisting of curved or linear amyloid fibrils, associated with various cell reactions. The electron-microscopic histochemical study showed that they strongly stained with periodic acid-silver methenamine stain. A similar phenomenon was noticed in the spicules or bundles of amyloid fibrils in primary and secondary renal amyloidosis. With the cationic reagent toluidine blue 0, proteoglycan-like structures were observed around amyloid bundles and nodules, but not on each fibrils. Based on these results, we postulate that there is a close relationship between ultrastructural features and histochemical characteristics in beta 2-MG amyloid fibrils.  相似文献   
10.
A 22-year-old man was urgently admitted for pneumothorax. He continued complaining of exertional dyspnea and dry cough after the pneumothorax healed. About three months later, an atypical pulmonary mycobacteriosis by mycobacterium kansasii was identified. Exertional dyspnea increased after chemotherapy was administered, and the patient was readmitted because of difficulty in daily life activities. Chest radiographs and CT scans showed bilateral pulmonary hyperinflation and a narrowed heart shadow. There was also marked combined ventilatory impairment, as identified by a respiratory function test. Furthermore, the histological findings of surgically removed lung tissue revealed accumulation of lymphocytes in the wall of a small bronchus. Idiopathic bronchiolitis obliterans was diagnosed from the clinical course and clinical findings. The patient is now being monitored and is awaiting lung transplantation.  相似文献   
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