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1.
The carcinogenicity of dextran and 3 kinds of dextran sulfate sodium with different molecular weights and almost the same sulfur content were compared in ACI rats. Dextran sulfate sodium of molecular weight 54,000 showed a strong carcinogenic activity when it was given orally as 2.5% diet, whereas dextran sulfate sodium of molecular weight 520,000 and 9500 and dextran showed no significant carcinogenicity, i.e. the peak of carcinogenic activity of dextran sulfate sodium appeared at molecular weight 54,000, and dextran sulfates with larger or smaller molecular weights had no carcinogenic activity.  相似文献   
2.
OBJECTIVES: To determine the value of the loss of expression of E-cadherin and cadherin associated molecules as useful markers for both prognosis and chemosensitivity in bladder cancer patients who have undergone radical cystectomy. PATIENTS AND METHODS: In 55 paraffin embedded specimens of radical cystectomy at our hospital from 1982 to 2000, the expression of E-cadherin, alpha-, beta- and gamma-catenin was examined by immunohistochemical staining. To evaluate the prognostic significance of these molecules, Kaplan-Meier survival curves were constructed and a statistical analysis was calculated by a log-rank test. A multivariate test (tumor stage, tumor grade, lymph node metastasis, configuration, the expression of E-cadherin, alpha-, beta- and gamma-catenin) was performed to detect prognostic markers. RESULTS: Normal expression was found in 33 cases (60.0%) for E-cadherin, 29 (52.7%) for alpha-catenin, 31 cases (56.4%) for beta-catenin, and 31 cases (56.4%) for gamma-catenin. The expression patterns for E-cadherin, alpha-, beta- and gamma-catenin were significantly correlated with each other (P < 0.01). Survival analysis showed a significant difference between normal and aberrant expression in each staining. A multivariate analysis revealed that the expression of alpha- catenin was an independent prognostic factor (P = 0.0191). In 23 patients that received adjuvant chemotherapy, there was a significant difference in survival between the normal and aberrant expression of alpha-catenin, but not other molecules. CONCLUSION: Alpha-catenin may not only be a good prognostic marker, but also one of key molecules that determine the chemosensitivities in patients with invasive bladder cancer.  相似文献   
3.
The mechanisms of hypertensive nephrosclerosis are not fully understood. In experimental models of the disease, inflammatory reactions such as macrophage infiltration play an important role. In human hypertensive nephrosclerosis, however, there have been few studies examining the role of inflammation histologically. We investigated whether the number of infiltrating macrophages was increased in human hypertensive nephrosclerosis, and evaluated the effects of a blockade of the renin-angiotensin system on clinical and histological findings. We examined macrophage infiltration using immunohistochemistry in renal biopsy specimens obtained from 16 patients with hypertensive nephrosclerosis, 5 patients with IgA nephropathy, 5 patients with membranous nephropathy, and 5 patients with minimal change nephrotic syndrome. The number of infiltrating macrophages in glomeruli was significantly larger in the patients with hypertensive nephrosclerosis than in those with minimal change nephrotic syndrome. The patients with hypertensive nephrosclerosis were divided into groups based on their use of antihypertensive agents at the time of renal biopsy. We investigated the effects of antihypertensive agents on clinical findings, macrophage infiltration, and monocyte chemoattractant protein-1 expression. There was no difference in clinical findings between the hypertensive groups. The numbers of infiltrating macrophages and monocyte chemoattractant protein-1-positive cells in glomeruli were significantly smaller in patients treated with an angiotensin-converting enzyme inhibitor or angiotensin II type 1 receptor blocker, whereas calcium channel blockers had no influence on histological findings. In conclusion, inflammation is involved in the progression of human hypertensive nephrosclerosis and the inflammatory process is inhibited by blocking the renin-angiotensin system.  相似文献   
4.
OBJECTIVE: Neuropsychiatric disturbances are common and burdensome symptoms of dementia. Assessment and measurement of neuropsychiatric disturbances are indispensable to the management of patients with dementia. Neuropsychiatric Inventory (NPI) is a comprehensive assessment tool that evaluates psychiatric symptoms in dementia. We translated the NPI-Caregiver Distress Scale part of NPI (NPI-D) and NPI-Brief Questionnaire Form (NPI-Q) into Japanese and examined their validity and reliability. SUBJECTS AND METHODS: The subjects were 152 demented patients and the caregivers who lived with them. These patients consisted of 76 women and 76 men; their mean age was 73.9 +/- 7.8 (S.D.; range: 49 to 93) years. Their caregivers consisted of 46 men and 106 women; their mean age was 65.0 +/- 11.4 (S.D.; range: 35 to 90) years. The Mini-Mental State Examination (MMSE) was conducted with all patients and NPI-Q, NPI, NPI-D, and the Zarit caregiver burden interview (ZBI) were conducted with all caregivers. We examined validity of NPI-D by comparing its score with the MMSE and ZBI scores, and the validity of NPI-Q by comparing its score with the NPI and NPI-D scores. In order to evaluate test-retest reliability, NPI-D was re-adopted to 30 randomly selected caregivers by a different examiner one month later and NPI-Q was re-executed by 27 randomly selected caregivers one day later. RESULTS: Total NPI-D score was significantly correlated with ZBI (rs = 0.59, p < 0.01). Test-retest reliability of NPI-D was adequate (ri = 0.47, p < 0.01). Total NPI-Q severity score and distress score were strongly correlated with NPI (r = 0.77, p < 0.01) and NPI-D (r = 0.80, p < 0.01) scores, respectively. Test-retest reliability of the scores of NPI-Q was acceptably high (the severity score; ri = 0.81, p < 0.01, the distress score; ri = 0.80, p < 0.01). CONCLUSION: The Japanese version of NPI-D and NPI-Q demonstrated sufficient validity and reliability as well as the original version of them. These are useful tools for evaluating psychiatric symptoms in demented patients and their caregivers' distress attributable to these symptoms.  相似文献   
5.
We report the case of a 52-year-old female with middle-ear paraganglioma masquerading as a traumatic facial palsy, and describe the diagnostic steps and surgical treatment by the tympanomastoid approach.  相似文献   
6.
Calorie restriction is important in managing patients with maturity onset diabetes mellitus (NIDDM). The effect of such restriction on calcium metabolism is not known. The objective of this study was to determine whether patients on calorie restricted diets would show any modification of parathyroid hormone (PTH) and calcitonin (CTN). The serum levels of PTH and CTN were measured by radioimmunoassays in 269 patients with NIDDM. The patients were divided into two groups depending on the intake of calorie, and PTH and CTN were monitored for 2 years. Plasma levels of vitamin D were measured by competitive protein binding assays before and after each program. The level of PTH (520.8±266.0 pg/ml) (mean±S.D.) was significantly (P<0.01) higher in 109 diabetic patients whose calorie intake was restricted for 2 years (diet (D) group) as compared with that (256.6±103.8 pg/ml) of 160 diabetic patients whose calorie intake was not restricted (non-diet (ND) group). The daily oral calcium intake of the two groups did not differ significantly. We found no significant difference in the serum PTH level in the ND groupVS. normal control subjects (248.8±98.4, N=78). The serum calcium concentration and the amount of calcium excreted in urine were slightly but significantly (P<0.01) lower in the D than in the ND group. The rate of tubular reabsorption of phosphate (% TRP) was significantly lower in the D group than that in the ND group (P<0.01). The serum CTN level was significantly (P<0.01) lower in the D group (33.9±11.3 pg/ml) than in the ND group (64.9±21.2 pg/ml) 2 years after each treatment. The plasma 1,25-(OH)2-vitamin D level was significantly (P<0.01) lower in the D group (22.2±6.6 pg/ml) than in the ND group (50.6±4.2 pg/ml). When the restriction of calorie intake in the D group was canceled, their PTH levels decreased, which was accompanied by increase in the 1,25-(OH)2-vitamin D levels, whereas their CTN levels were unchanged. These observations suggested that a restricted calorie intake is a risk factor for secondary hyperparathyroidism as well as for a low serum level of CTN in patients with NIDDM.  相似文献   
7.
By the end of 1988, seventy five cases after pulmonary resection for lung cancer and one case after pulmonary resection for basal cell hyperplasia were examined with fiberoptic bronchoscopy as postoperative follow up. Endobronchial tumor was detected in 14 cases. In seven cases, endobronchial tumor was located at site far from the surgical bronchial anastomosis. These tumors were suspected as second lung cancer as long as examined by fiberoptic bronchoscopy. Histological type of all of these was squamous cell carcinoma. Re-operations were performed in five cases and two of them were early lung cancer. In 6 cases (13.6%) among 44 cases examined with fiberoptic bronchoscopy after pulmonary resection for central type squamous cell carcinoma, second lung cancer was detected. In the case of central type squamous cell carcinoma, usually the tumor appears to be of same histological type and at same location. Among those cases those who smoke heavily should be separated as high risk group. If this group is followed with fiberoptic bronchoscopy or sputum cytological examination, it is more possible to detect second lung cancer at an early stage.  相似文献   
8.
An automated measurement of total and free hydroxyproline in serum or urine is presented that uses flow injection analysis. After exclusion of nonspecific substances, hydroxyproline was oxidized by chloramine- T and L-cysteine with Ehrlich's reagent. The linearity obtained was from 3.8μmole/ L to 1.22 mmole/L with good precision (CV <3%). Comparison of the proposed method with HPLC yielded r = 0.939 as the correlation coefficient. Reference intervals of free and total hydroxyproline are 1.4–9.7 μmole/L, 3.8–27.2 μmole/L for serum, and 10.0–72.5 μmole/L, 25.2–303.6 μmole/L for urine, respectively. Serum free and total hydroxyproline levels in renal osteodystrophy patients on maintenance hemodialysis (N = 71) were significantly higher than in controls (P<0.0001). This method is superior to the use of HPLC with regard to stability of the color reaction. The measurement of serum free and total hydroxyproline is a useful marker for therapeutic observation of renal osteodystrophy patients. © 1994 Wiley-Liss, Inc.  相似文献   
9.
Shionogi carcinoma 115 (SC115), an androgen-dependent mouse mammary tumor, rapidly loses its androgen responsiveness after androgen withdrawal. The growth of this tumor can also be stimulated by high doses of estrogen or glucocorticoid. In the present study, the maintenance of hormone-responsive growth of SC115 tumors with a high dose of estrogen was examined in castrated male mice using an SCI 15 subline obtained by serial transplantations of SCI 15 tumors in estrogen-treated castrated mice for 3 years (30 generations) (subline E2). Seed tumors from both SC115 and subline E2 could rapidly grow in castrated mice given daily injections of testosterone propionate (TP), 17β-estradiol (E2), or dexamethasone (Dex) (100 μg/mouse/day) but not in those given vehicle alone. Although SCI 15 and subline-E2 tumors grown with TP or Dex showed temporary regression after steroid withdrawal, the tumors grown with E2 did not show such temporary regression. The TP-, E2-, or Dex-induced growth of subline-E2 tumors was almost the same as that of the original SCI 15 tumors. However, responsiveness to androgen, estrogen or glucocorticoid of both tumors disappeared within one passage in steroid-depleted castrated mice. The present findings demonstrate that the loss of responsiveness to androgen as well as to high doses of estrogen or glucocorticoid of SCI 15 tumors can be prevented in castrated mice not only with androgen but also with high doses of estrogen.  相似文献   
10.
Subdural hygroma is a frequent delayed complication of head trauma. Most hygromas are clinically 'silent' and a few cases have shown slow deterioration in the chronic stage. We report a case of subdural hygroma showing unique radiological findings and rapid deterioration. A 74-years-old female presented with a mild headache and consciousness disturbance after head injury. Computed tomography showed a midline shift as a result of two components piling up in the subdural space; the outer components showed low density, the inner components high density. Magnetic resonance imaging demonstrated that these two subdural components were subdural hygroma and subarachnoid hematoma. Simple burr hole irrigation, rather than large craniotomy, was thought to be more appropriate treatment to reduce the mass effect. Simple burr hole irrigation was performed to remove the subdural hygroma and the patient showed an excellent recovery. Careful examination of the radiological findings prevented an unnecessary procedure in this case. A possible mechanism of this phenomenon is discussed.  相似文献   
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