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1.
PURPOSE: To evaluate the pattern of neurological late effects in patients who have received surgery only for a brain tumor in childhood and to identify possible risk factors for neurological sequelae. PATIENTS AND METHODS: The medical, histologic, and operative records were reviewed for 65 consecutive patients operated for a benign brain tumor from 1970 to 1997, and all patients were re-examined after a median length of follow-up of 10.7 years. Thirty-four patients had posterior fossa tumors, 22 patients had cerebral hemisphere tumors, and nine patients had midline tumors. RESULTS: At the time of follow-up, 20 patients (31%) had no neurological deficits, 22 patients (34%) had minor deficits that did not interfere with their daily life activities, and 23 patients (35%) had moderate or severe deficits such as severe ataxia, spastic paresis, seriously reduced vision, or epilepsy with more than two seizures per year. Fourteen of the 31 patients (45%) registered with ataxia preoperatively had recovered fully. Six of seven patients had persistence of a pre- or postoperatively developed hemiparesis. Thirteen of 23 patients had persistence of cranial nerve deficits that developed second to surgery. Fifty-five percent of the 18 patients with seizures at diagnosis were seizure-free at follow-up. At follow-up both ataxia and hemiparesis were significantly more frequent among females (P =.02 and P =.03, respectively). CONCLUSION: In patients who received operation as the only treatment for their brain tumor, there was a good chance of total or partial recovery of preoperative and postoperative neurological deficits, although only one third of the patients will have no long-term neurological deficits.  相似文献   
2.
The effect of 18 months' inhibition of angiotensin-converting enzyme by captopril on the leakage of fluorescein through the blood-retina barrier was examined in a prospective, randomized control study of 20 normotensive insulin-dependent diabetic patients with nephropathy and background retinopathy. After 18 months, 15 patients remained in the study. Fluorescein leakage remained nearly unchanged in the captopril-treated group, being 4.1 ± 4.1 (mean ± SD) × 10–7 cm/s at baseline and 4.2±4.1 × 10–7 cm/s after 18 months' treatment. The permeability increased significantly (P<0.01) from 3.3±2.2 × 10–7 cm/s to 5.6±3.5 × 10–7 cm/s at 18 months in the control group. Arterial blood pressure was nearly constant in both groups throughout the study. The results indicate that angiotensin-converting enzyme inhibition with captopril can arrest or delay a progressive breakdown of the blood-retina barrier in normotensive insulin-dependent diabetic patients with nephropathy and background retinopathy.The authors have no commercial or proprietory interest in the drugs or instruments used in this study  相似文献   
3.
Caffeine is sequentially metabolized by cytochrome P4501A2 (CYP1A2), N-acetyltransferase (NAT) and/or xanthine oxidase (XO). In the present study the activity of these three enzymes was estimated from ratios of the metabolites formed from dietary caffeine and excreted into the urine collected as spot samples. In the urine samples from 10 out of 377 subjects concentrations of caffeine metabolites were too low to allow reliable measurements of the ratios. In 335 healthy subjects the NAT activity showed a typically bimodal distribution with 47% fast acetylators and 53% slow acetylators, consistent with a Danish population. The ratios reflecting CYP1A2 and XO activities were log normal and normal distributed, respectively. In 103 non-smoking men and 90 non-smoking women the ratio of caffeine metabolites expressing CYP1A2 activity was 4.7 +/- 1.6 and 4.3 +/- 1.9 as compared to 7.8 +/- 2.5 and 7.3 +/- 3.0 in 31 male and 25 female subjects smoking 10 cigarettes/day or more respectively, verifying induction of CYP1A2 by tobacco (P less than 0.05), but minimal sex-related differences. In 12 non-smoking pregnant women and in 28 women using oral contraceptives the CYP1A2 ratio was 29 and 20% reduced respectively (P less than 0.05). In a multivariate analysis the only significant predictor of the XO ratio was the consumption of caffeine with an increase of 2% per cup of coffee or equivalent (P less than 0.05). In 23 healthy male subjects 30 days of vigorous exercise increased the CYP1A2 ratio by 70% and the XO ratio by 42% (P less than 0.05), but left the NAT ratio unchanged. In nine healthy volunteers daily ingestion of 500 g of broccoli for 10 days increased the CYP1A2 ratio by an average of 12% (P less than 0.05), compared to a control period with ingestion of an equivalent weight of non-cruciferous green vegetables. The ratios of metabolites from dietary caffeine in spot urine samples offer ethical, non-invasive and reliable estimates of CYP1A2, NAT and XO. These enzymes are highly relevant for the bioactivation of potentially toxic compounds and the formation of oxygen radicals. The method is applicable in large-scale epidemiological studies, allowing, for example, prospective testing of the relationship between these enzyme activities and the development of disease. Exercise may increase CYP1A2 activity to a magnitude corresponding to heavy smoking, as well as XO by mechanisms that remain to be clarified.  相似文献   
4.
Long-term dopamine replacement therapy of Parkinson's disease leads to the occurrence of dyskinesias. Altered firing patterns of neurons of the internal globus pallidus, involving a pathological synchronization/desynchronization process, may contribute significantly to the genesis of dyskinesia. Levetiracetam, an antiepileptic drug that counteracts neuronal (hyper)synchronization in animal models of epilepsy, was assessed in the MPTP-lesioned marmoset model of Parkinson's disease, after coadministration with (1) levodopa (L-dopa) or (2) ropinirole/L-dopa combination. Oral administration of levetiracetam (13-60 mg/kg) in combination with either L-dopa (12 mg/kg) alone or L-dopa (8 mg/kg)/ropinirole (1.25 mg/kg) treatments was associated with significantly less dyskinesia, in comparison to L-dopa monotherapy during the first hour after administration. Thus, new nondopaminergic treatment strategies targeting normalization of abnormal firing patterns in basal ganglia structures may prove useful as an adjunct to reduce dyskinesia induced by dopamine replacement therapy without affecting its antiparkinsonian action.  相似文献   
5.
6.
Nine human small-cell lung cancer cell lines were treated with transforming growth factor beta 1 (TGF-beta 1). Seven of the cell lines expressed receptors for transforming growth factor beta (TGF-beta-r) in different combinations between the three human subtypes I, II and III, and two were receptor negative. Growth suppression was induced by TGF-beta 1 exclusively in the five cell lines expressing the type II receptor. For the first time growth suppression by TGF-beta 1 of a cell line expressing the type II receptor without coexpression of the type I receptor is reported. No effect on growth was observed in two cell lines expressing only type III receptor and in TGF-beta-r negative cell lines. In two cell lines expressing all three receptor types, growth suppression was accompanied by morphological changes. To evaluate the possible involvement of the retinoblastoma protein (pRb) in mediating the growth-suppressive effect of TGF-beta 1, the expression of functional pRb, as characterised by nuclear localisation, was examined by immunocytochemistry. Nuclear association of pRb was only seen in two of the five TGF-beta 1-responsive cell lines. These results indicate that in SCLC pRb is not required for mediation of TGF-beta 1-induced growth suppression.  相似文献   
7.
More suicides than expected (standardized mortality ratio=1.3; 95% confidence interval=1.1-1.6) compared to the population risk were found among Danish women with a diagnosis of non-melanoma skin cancer in the period 1971-1999 but not among men. The increased risk might be associated with a different personality type in this cancer group.  相似文献   
8.
BACKGROUND: The occurrence of small vessel arteriosclerosis in the myocardium, kidney, and lung in dogs with naturally occurring myxomatous mitral valve disease has not been previously investigated systematically. METHODS: Twenty-one dogs with naturally occurring congestive heart failure and 21 age-matched, sex-matched, and weight-matched control dogs underwent extensive pathological and histopathological examination. Morphometry and scoring of tissue sections were used to measure arterial narrowing and fibrosis in the myocardium, kidney, and lung; and intimal thickness and plaque formation in the aorta and pulmonary artery. RESULTS: Dogs with congestive heart failure had significantly more arterial narrowing in the left ventricle (P < .003), lung (P < .0001), and kidney (P < .02); intimal-medial thickening in the pulmonary artery (P = .04); and fibrosis in the left ventricle (P < .0001) than control dogs. However, they did not have more plaque formation or intimal-medial thickening in the aorta than controls. There was significantly more arterial narrowing in papillary muscles than in all other locations in dogs with congestive heart failure (P < .002). In control dogs, arterial changes were less pronounced and did not differ in different locations. CONCLUSIONS: Dogs with naturally occurring myxomatous mitral valve disease have significantly more arterial changes in the myocardium, lung, and kidney, and significantly more fibrosis in the myocardium than control dogs. This could have important implications in the management of myxomatous mitral valve disease and raises interesting questions about the occurrence and importance of intramural small vessel disease in humans with primary mitral valve prolapse.  相似文献   
9.
This paper investigates the association between individually measured socioeconomic status (SES) and all-cause survival in colorectal cancer patients, and explores whether factors related to the patient, the disease, or the surgical treatment mediate the observed social gradient.  相似文献   
10.

Background  

Official guidelines that promote evidence-based and cost-effective prescribing are of main relevance for obvious reasons. However, to what extent these guidelines are followed and their conditioning factors at different levels of the health care system are still insufficiently known.  相似文献   
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