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51.
The formal-normative concept of risk in natural and technical sciences is oriented toward effects and damage. A complete understanding of cause and effect relationships is necessary, however, it is normally not available and uncertainties are inadequately taken into account. Risk is distinguished from safety in the formal-normative context. Safety itself can only be understood, however, in relation to uncertainty and therefore to damage. In the legal context, risk is defined by the triad of danger, risk, and residual risk. Risk in the legal context is limited to the domain between danger and residual risk. However, uncertainty has to be considered as distinct from residual risk. In social sciences risk is distinguished from danger. A difference is made between people who decide, i.e., regulators, and those who are affected by the decision. People who decide attribute consequences of the decision and the involvement of risks to their own decision. Concern, however, is grounded in decisions of others, in non-participation, and possible damage is therefore realized as danger and not as risk.  相似文献   
52.
A 42-year-old man with left posterior inferior cerebellar artery (PICA) infarction presented with akinetic mutism and cognitive impairment. Initially he suffered from akinetic mutism and MRI-documented infarction in the distribution of the left PICA. Twelve days later he developed cognitive impairment. Neuropsychological tests were performed, with the results corrected for age and education being compared with published Korean norms. Impaired performances were evident on executive function testing, with difficulties in planning, abstract reasoning, set-shifting, and perseveration. Akinetic mutism and cognitive-affective syndrome may be a manifestation of unilateral PICA infarction.  相似文献   
53.
A patient with chronic cerebral paragonimiasis began to have new motor seizures of the right face manifested by clonic contractions that occurred several hundred times a day, consistent with simple partial status epilepticus. Ictal electroencephalogram discharges started from the left frontal region and then spread to the left hemisphere with left frontal maximum. But clinical seizures were limited to the right face. The frequent partial seizures were controlled by the intravenous infusion of phenytoin. Brain magnetic resonance imaging showed multiple conglomerated round nodules with encephalomalacia in the left temporal and occipital lobes. Applying the technique of ictal-interictal single-photo emission computed tomography subtraction, the authors were able to localize the focal ictal-hyperperfusion on left precentral cortex adjacent to the lesions that correspond to the anatomical distribution of left face motor area.  相似文献   
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55.
OBJECTIVE: To evaluate the pattern of contrast enhancement with Levovist on coded harmonic angiographic ultrasonography of hepatic hemangiomas. METHODS: Twenty hemangiomas were evaluated with coded harmonic angiographic ultrasonography and a microbubble contrast agent. Verification of the diagnosis of a hemangioma was made by means of dynamic computed tomography (n = 8), dynamic magnetic resonance imaging (n = 1), radionuclide scanning (n = 6), or follow-up ultrasonography (n = 5). Ultrasonographic images were obtained before contrast agent administration and with a bolus injection of 2.5 g of a microbubble contrast agent (300 mg/mL Levovist; Schering AG, Berlin, Germany) every 10 to 15 seconds for 5 minutes. The contrast enhancement patterns of the 20 hemangiomas were assessed. RESULTS: The tumor diameters as measured on ultrasonography were 7 to 97 mm (mean, 26.7 mm). Of the 20 hemangiomas, peripheral globular enhancement with progressive centripetal fill-in was shown in 15 (75%), rimlike enhancement with progressive centripetal fill-in was shown in 2 (10%), and homogeneous enhancement was shown in 1 (5%). In the remaining 2 lesions (10%), the enhancement patterns could not be seen, because they were not found on coded harmonic angiographic ultrasonography. CONCLUSIONS: Coded harmonic angiographic ultrasonography with a microbubble contrast agent can depict the typical enhancement pattern in most hepatic hemangiomas.  相似文献   
56.
Otitis media is a common childhood disease caused by multiple factors. Understanding the pathogenesis of otitis media is important in the diagnosis and management of it. The mode of therapy should be chosen depending on the type and stage of the disease. Treatment options available to an otolaryngologist include antibiotics, tympanocentesis, myringotomy and tympanostomy tube insertions, adenoidectomy with or without tonsillectomy, exploratory tympanotomy, atympanoplasty, and mastoidectomy.  相似文献   
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58.
This is the first preliminary report among two consecutive papers. Partial mastectomy(PM), axillary lymph node dissection(AD) and radiotherapy (RT) were performed on seventeen operable breast cancer patients who had been admitted from April 1991 to March 1992 to the department of surgery, Yongdong Severance Hospital for improved cosmetic appearance and better survival rate. Of seventeen patients, 47% were T1 lesion and 76% were stage I and II. Extensive intraductal component(EIC) within or around the tumor was also analyzed. Twenty nine per cent of the patients were EIC positive. The mean number of axillary lymph nodes was 21.5 after PM with AD and 20.5 after mastectomy. For radiotherapy, 4,500 rad was delivered to the breast parenchyma and 1,600 rad of boost to the primary tumor site using the electron beam method after surgery. All patients have since been living well without any local recurrence and were satisfied with breast preservation for the one-year follow-up period. We concluded that the PM, AD and RT can be another surgical treatment modality of breast cancer. A longer follow-up data will be followed on the second paper.  相似文献   
59.
This paper aims to review the evidence for long‐term effectiveness of weight loss on cholesterol, high‐density lipoprotein (HDL), low‐density lipoprotein (LDL) and triglycerides in overweight/obese people. Current evidence is mostly based on short‐term studies. A systematic review of long‐term lipid outcomes of weight loss in studies published between 1966 and 2001, was conducted. Inclusion criteria included all cohort studies and trials carried out on participants with body mass index of greater than or equal to 28 kg m?2. Studies had at least two weight change measurements and follow‐up of more than 2 years. Thirteen long‐term studies with a follow‐up of more than 2 years were included. Cholesterol has a significant positive linear relationship with weight change (r = 0.89) where change in weight explains about 80% of the cholesterol difference variation (Adj R2 = 0.80). For every 10 kg weight loss a drop of 0.23 mmol L?1 in cholesterol may be expected for a person suffering from obesity or are grossly overweight. Weight loss has long‐term beneficial effects especially on LDL and cholesterol. Weight loss in obese patients should be encouraged and sustained.  相似文献   
60.
BACKGROUND/AIMS: Carcinogenesis is characterized by the abnormal regulation of cell cycle. The abnormal expression of the regulators of cell cycle may be related to the prognosis. Since the clinical significance of the expression of the three proteins in colorectal carcinomas is still controversial, we evaluated the prognostic value of the expression of cyclin E, p27 and mutant p53 in stage II colorectal cancer. METHODS: The expression levels of cyclin E, p27 and mutant p53 proteins in 41 patients with stage II colorectal carcinomas were analyzed by immunohistochemistry. RESULTS: In the univariate analysis, the level of CEA at diagnosis was associated with disease relapse. In the multivariate analysis, the clinicopathological variables such as age, gender, site of primary tumor, tumor size, state of tumor differentiation and preoperative plasma CEA level were not associated with disease relapse. When Kaplan-Meier survival curves were constructed to determine the prognosis, cyclin E, p27 and mutant p53 expressions did not predict poor prognosis. CONCLUSIONS: Our results suggested that the expression of cyclin E, p27 and mutant p53 proteins did not predict the clinical outcome in the stage II colorectal carcinomas.  相似文献   
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