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941.
We present a case of plexiform neurofibroma involving the retroperitoneum, mesentery, and liver in a 5-year-old boy who underwent
evaluation for extent of a palpable left neck mass. The mass had intrathoracic extension with great vessel encasement and
extension into the abdomen. Abdominal CT revealed a diffuse low-attenuation non-enhancing mass encasing the retroperitoneal
vessels with serpiginous extension into the liver along the portal vein. This spread pattern of plexiform neurofibroma is
an unusual manifestation of neurofibromatosis in a young child.
Received: 30 October 2000 Accepted: 5 March 2001 相似文献
942.
BACKGROUND: Chronic alcohol consumption elicits an increase in catecholamine release, which may be detrimental to heart function. Adenosine attenuates adrenergic stimulation via an adenosine receptor-mediated antiadrenergic action. This study investigated the effect of ethanol on adenosine antiadrenergic actions and adenosine release in the rat heart. METHODS: Rats were pair-fed a liquid diet with or without ethanol for 4 weeks or 8 months. Hearts were isolated for determination of contractile function, and coronary effluents were collected for adenosine content. Dose-response relationships for phenylisopropyladenosine (PIA) were determined for hearts adrenergically stimulated by isoproterenol. Experiments were also conducted with normal hearts with or without ethanol (25 mM) administered acutely. The effect of PIA on adenylyl cyclase activities of adrenergic-stimulated crude membrane preparations obtained from alcoholic and nonalcoholic hearts was determined. RESULTS: Acute ethanol reduced basal adenosine release by 39%, but it did not significantly decrease adenosine release during adrenergic stimulation. In hearts chronically treated with ethanol for 4 weeks, adenosine release values before and during adrenergic stimulation were significantly reduced from control values. After 8 months of ethanol, adenosine release was similar with or without adrenergic stimulation. PIA 50% inhibiting concentration (IC50) values for contractile function were reduced from pair-fed control values. Acute ethanol did not significantly change the PIA IC50 value. Chronic ethanol reduced the PIA IC50 for adenylyl cyclase by 96%. CONCLUSIONS: Chronic ethanol treatment increases the antiadrenergic action of adenosine by mechanisms that seem independent of changes in adenosine concentration. Therefore, adenosine-induced cardioprotection against increased catecholamine stimulation is enhanced by ethanol. 相似文献
943.
Case report: infantile hemangioendothelioma 总被引:1,自引:0,他引:1
During a routine physical exam, an 18-day-old male infant was noted to have persistent abdominal distention and prominent vascular markings over his abdominal wall. Laboratory studies were significant for an elevated alpha-fetoprotein level of 7051 ng/ml and mild anemia. Abdominal ultrasound and CT scan demonstrated a large, heterogeneous mass in the lateral segment of the left lobe of the liver. Although the patient did not have congestive heart failure or coagulopathy, surgical resection was performed to rule out malignancy. Histopathologic examination revealed a type I infantile hemangioendothelioma. This case report reviews the presentation and treatment of infantile hemangioendotheliomas and the differential diagnosis of neonatal hepatic neoplasms. 相似文献
944.
945.
946.
Okunieff P Li M Liu W Sun J Fenton B Zhang L Ding I 《American journal of clinical oncology》2001,24(5):491-495
Various members of the fibroblast growth factor (FGF) family of proteins have been shown to protect against acute and late radiation damage of normal tissues. Protection of the small bowel, for example, occurs via both increased proliferation and reduced apoptosis. Other beneficial effects of FGFs include promotion of bone growth, pneumonitis prevention, and apoptosis suppression of endothelium in vivo and in vitro after irradiation. This protection against radiation requires only low and infrequent doses of FGFs. Two newly identified members of the FGF family, FGF7 and FGF10, have effects similar to many of the other FGF family proteins, but with more specificity for normal epithelial structures. For this reason, they have also been named keratinocyte growth factors one and two (KGF1 and KGF2, respectively). We therefore examined the potential utility of KGFs for radioprotection of the bone marrow and small bowel and examined safety issues concerning their adverse effects on KHT sarcoma. The results suggest that KGFs could be safely used to prevent radiation toxicity of the abdomen or pelvis and may in fact improve tumor response to radiation. 相似文献
947.
Fenton BM 《International journal of radiation oncology, biology, physics》2001,49(3):799-808
PURPOSE: To examine the effects of hydralazine on vascular perfusion and hypoxia in spontaneous vs. first generation and long-term transplanted murine tumor models. METHODS AND MATERIALS: Total anatomic blood vessels were quantified using image analysis of CD31 stained frozen sections, perfused vessels by i.v. injection of fluorescent DiOC(7), and tumor hypoxia was measured using the EF5 hypoxia marker. KHT sarcomas, spontaneous mammary carcinomas, and first generation transplants of the spontaneous tumors were evaluated before and after i.p. administration of 5 mg/kg hydralazine. RESULTS: Although anatomic and perfused vessel spacings were similar among untreated tumors, response to hydralazine varied widely among the three tumor models. In KHT tumors, perfused vessel numbers decreased significantly at 30 min post-hydralazine, then recovered somewhat by 60 min. First-generation transplants showed a less substantial decrease in perfused vessels following hydralazine, which tapered off slightly by 60 min. Finally, spontaneous tumors had only a modest decrease in perfused vessel numbers, with complete recovery at 60 min. Although response of individual tumors varied widely, overall hypoxic marker uptake was significantly increased in both KHT and first generation tumors, and slightly reduced in the spontaneous tumors. CONCLUSION: Response to hydralazine varies substantially between transplanted and spontaneous tumor models. Results suggest that increased tumor pressure may be a critical factor in tumor response to hydralazine, possibly explaining tumor volume dependent variations. 相似文献
948.
Nasal nitric oxide and the nasal cycle 总被引:2,自引:0,他引:2
OBJECTIVES: To establish the relationship between nasal patency and the nitric oxide (NO) concentration in the nasal airways. METHODS: Unilateral nasal NO concentration (n = 11) and inhaled nasal NO concentration at oropharynx (n = 9) were measured in healthy adult volunteers. Subjects breathed normally through the nose with a known resistance (ranged from none to total occlusion) placed in one nostril. In a subgroup (n = 7), the unilateral nasal NO concentrations were determined with nasal cavity congestion induced by lateral decubitus. RESULTS: When the added nasal resistance was less than 6 cm H(2)0 per liter per second, the peak NO concentrations in the nose remained below 80 parts per billion (ppb). Thereafter, the higher the resistance, the greater the NO concentration. It was up to 1109.7 ppb when the front nostril was totally occluded. There was no correlation between oropharyngeal NO concentrations and resistance in the front of the nose (r = 0.4). There was a significantly negative correlation between nasal cavity volumes and nasal NO concentrations (r = -0.8, P <.001). CONCLUSIONS: Increases in nasal resistance to levels encountered in the nasal cycle and in recumbency augments the NO concentration within the obstructed side of the nose. Although that within the nose changes with patency, the NO concentration is constant down to the lower airways. The modulation role of the upper airways to the inhaled NO concentration remains unclear. 相似文献
949.
950.
Relationships between dietary intake and cognitive function level in Korean elderly people 总被引:1,自引:0,他引:1
L Lee SA Kang HO Lee B-H Lee JS Park J-H Kim IK Jung YJ Park JE Lee 《Public health》2001,115(2):133-138
We examined the relationship between dietary intake and cognitive performance in Korean elderly people. Data for dietary intake, anthropometric measurements and cognitive function tests were collected and the relationships of the variables were analyzed. A random sample of 210 men and 239 women in Korea, aged 60 and over, was selected. Subjects were free-living elderly people who had not experienced major cognitive function impairment. Main outcome measures, 24 h dietary recall method, food behaviour variables, anthropometrics indices, health variables, and Kwon's Mini-Mental State Examination for Koreans (MMSE-K) for cognitive function test. The prevalence rate of poor cognitive function (MMSE-K score < or = 19) of Korean elderly was 22.3%: women with poor cognitive function had a higher rate (31.0%) than that in men (12.3%). Cognitive ability was related negatively with age and positively with school education level. Female subjects of poor cognitive function had significantly lower intakes of total amount of foods, cereals, vegetables, fruits, milk, spices, and also, energy, protein, fat, carbohydrate, Ca, P, Fe, vitamin A, thiamin, riboflavin, and niacin than those of the normal cognitive score (> or = 24) group (P < 0.05). Male subjects of poor cognitive function had significantly lower intakes of fruits, fiber, and vitamin C than the normal subjects (P < 0.05). The MMSE-K score of female subjects showed a significant positive correlation with total amount of foods, cereals, beans, fruits, milk, oil, spices, and energy, protein, fat, carbohydrate, Ca, Fe, P, riboflavin and niacin intakes. The consumption of adequate nutrients, by taking sufficient amounts and variety of foods, may be important in maintaining adequate cognitive function in elderly Koreans. 相似文献