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991.
K. Norén C. Weistrand F. Karpe 《Archives of environmental contamination and toxicology》1999,37(3):408-414
The concentrations of chlorinated biphenyls (CBs), 1,1-bis(4-chlorophenyl)-2,2-dichloroethene (DDE), hexachlorobenzene (HCB),
and the methylsulfonyl metabolites of CBs (MeSO2-CBs) and DDE (MeSO2-DDE) were determined in human plasma samples and in the fractions obtained by ultracentrifugation of plasma into very-low-density
(VLDL), low-density (LDL), high-density (HDL) lipoprotein and lipoprotein depleted (LPDP) fractions (containing primarily
albumin). The concentrations of triacylglycerols, cholesterol, phospholipids, and apolipoprotein B (apoB) were determined.
The organochlorine compounds were associated with all fractions, but predominantly with the LPDP fraction. On an average 44%
of CBs, 61% of MeSO2-CBs, 73% of DDE, 77% of MeSO2-DDE, and 45% of HCB were distributed in the LPDP fraction. A tendency to greater association of 3-methylsulfonyl substituted
than of corresponding 4-methylsulfonyl substituted chlorobiphenyls to the LPDP fraction was noticed. Among the lipoprotein
fractions, LDL was the main carrier of HCB, DDE and CBs. MeSO2-DDE was predominantly found in HDL and MeSO2-CBs were distributed equally among the LDL and HDL fractions. Calculating the concentrations of organochlorine compounds
in relation to the content of apoB, the levels were about 10 times higher in VLDL than in LDL.
Received: 24 April 1998/Accepted: 24 April 1999 相似文献
992.
M Achón L Reyes E Alonso-Aperte N Ubeda G Varela-Moreiras 《The Journal of nutrition》1999,129(6):1204-1208
There is new evidence that good folate status may play a critical role in the prevention of neural tube defects and in the maintenance of adequate homocysteine levels, an amino acid recently identified as a risk factor for cardiovascular disease. This has led to different folate recommendations, all of them much higher than the present dietary recommendations. Folic acid is a water-soluble vitamin with a low potential toxicity. However, the possible consequences of long-term, high folate intakes are unknown. Therefore, the present study was undertaken to determine the effects of long-term, high dietary folate supplementation on gestational and nutritional markers in pregnant and virgin rats. Four groups of Wistar rats were classified on the basis of physiological status (virgin or pregnant) and the experimental diets administered (folic acid supplemented, 40 mg/kg diet; or control diet, 2 mg folic acid/kg diet). Rats were fed their respective diets for 3 wk. Two critical periods were used for metabolic balance studies (experimental d 1-5 and 17-21), which involved the determination of fat and protein digestibilities as well as metabolic protein utilization (MPU) and net protein utilization (NPU). Gestational development (number of live fetuses) was adequate in both diet groups regardless of folate supplementation. However, body weight and vertex-coccyx length in fetuses from supplemented dams were less than (P < 0.0001) in fetuses of control dams. Fat and nitrogen digestibilities were not affected by supplementation, but MPU and NPU coefficients were significantly lower (P < 0.05) in the folic acid-supplemented groups, irrespective of physiological status, compared to control rats. These new findings of macro-micronutrient interactions caused by high folate supplementation are discussed on the basis that the vitamin may act as a xenobiotic more than as a nutrient. 相似文献
993.
Z Bencsik I Szabolcs M Góth O Dohán L Kovács I Kaszás G Gonda I Szilvási G Szilágyi 《Orvosi hetilap》1999,140(11):587-590
149 patients with adrenal incidentalomas were examined. Sixty-eight cases were histologically confirmed, five of them had ganglioneuromas. On the basis of these patients history current knowledge of this benign tumour was summarized. Histological and pathological characteristics of one tumour suggest that ganglioneuromas may develop by maturing of malignant neuroblastic tumours. The clinical symptoms (abdominal pain, meteorism) were local. In 2 of 5 cases mildly elevated levels of urinary vanillylmandelic acid and catecholamine could be measured. One patient had persisting hypertension after surgery. In an other patient previous diarrhoea stopped after the removal of tumour. On the basis of ultrasound and computertomographic features, the size and origin of a tumour and its relation to the surrounding organs can be well characterized. One patient was inoperable because of an infiltratively spreading tumour, but during five years of follow-up no tumour progression could be observed with computertomography. After surgery we could follow only 2 of 4 patients. Until now no recurrence of tumour were detected. 相似文献
994.
B Gulyás C Halldin P Karlsson Y H Chou C G Swahn P B?n?czk L Farde 《Orvosi hetilap》1999,140(30):1687-1691
Vinpocetine, a vinca alkaloid, is a therapeutic agent widely used in the treatment of acute and chronic stroke patients. To explore the uptake and distribution of vinpocetine in the primate brain, vinpocetine was labelled with 11C and positron emission tomography (PET) was used to measure the uptake and distribution of 11C-vinpocetine in the brain and the trunk of a cynomolgous monkey. HPLC was used to determine the concentration of vinpocetine and its labelled metabolites in blood and plasma. Following the radioligand's intravenous administration, after an initial peak, the total concentration of radioactivity in blood was relatively stable with time. The uptake of 11C-vinpocetine into the brain was rapid and about 5% of the total injected radioactivity was present in the brain two minutes after drug administration. These facts indicate that the compound passes the blood-brain barrier readily and enters the brain. The radioactivity uptake was heterogeneously distributed among brain regions. The highest concentrations were found in the thalamus, the basal ganglia and certain neocortical regions. In an earlier PET investigation on chronic stroke patients the highest increases in cerebral blood flow and glucose metabolism after intravenous vinpocetine treatment occurred in these anatomical structures. The heterogenous regional distribution of vinpocetine and the observation that the highest uptake values in brain structures go parallel with the greatest regional blood flow and glucose metabolic rate increases indicate that direct CNS effects of vinpocetine should be considered as an explanation for the therapeutic effects. The confirmation of this suggestion requires further investigations. 相似文献
995.
One hundred four cases of middle and low rectal villous and tubulovillous adenomas have been operated on with transanal polypectomy (8), transanal endoscopic microsurgery--TEM (80), anterior rectum resection with double stapled straight sigmoideorectosomy (7), and deep rectum resection, bi-directional mucosectomy and hand sutured straight sigmoideoanostomy (9). The option of the authors to remove the tumours in 5 cm to the dentate line are the transanal polypectomy or transanal mucosectomy corresponding to their size. The transanal endoscopic microsurgical technic is recommended to manage the polyps smaller than 4 to 5 cm in the middle rectum. The best radicallity in removal of the circular, extended villous adenomas could be achieved with deep rectum resection, bi-directional mucosectomy and transanal straight, hand sewn sigmoideoanostomy. 相似文献
996.
This study was designed and performed by the Universidad de Carabobo, Centro de Investigaciones Toxicológicas, Venezuela, and the University of Cincinnati Department of Environmental Health. The authors tested methodology and analyzed preliminary data on demographics, pesticide use, health, environment, and lifestyles in a farming community in Venezuela (population = 386; sample size = 81) to determine if pesticide misuse might have been contributing to public health problems. Questionnaire and geographic information were collected. There were statistically significant incidences of pesticide-related symptoms (p < .01) in farmers versus nonfarmers (odds ratio = 5.7; 95% confidence interval = 2.9, 18.8). In addition, in one area there was a cluster of farmers who experienced symptoms that appeared to be the result of foul air and proximity to farms where there was pesticide use. The results of the study indicated that this public health problem may have been associated with pesticide misuse; however, additional studies are needed to corroborate the findings. 相似文献
997.
The authors give a short account about the clinical histories of two patients: one with malignant systemic mastocytosis resulting in acute myeloid leukaemia, the other with indolent systemic mastocytosis. A brief review is reported about the physiological and pathophysiological role of mastocyte system. Benign and malignant types, classification of mastocyte proliferation are detailed, several distinct characteristics of clinical appearance, main aspects of diagnosis, therapy and prognosis in patients with different forms of systemic mastocytosis are briefly discussed. 相似文献
998.
Impact of chronic pain on health care seeking, self care, and medication. Results from a population-based Swedish study
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Andersson HI Ejlertsson G Leden I Scherstén B 《Journal of epidemiology and community health》1999,53(8):503-509
STUDY OBJECTIVE: To explore individual and social factors that could predict health care utilisation and medication among people with chronic pain in an unselected population. DESIGN: A mailed survey with questions about pain and mental symptoms, disability, self care action, visits to health care providers, and medication. SETTING: General populations in two Swedish primary health care (PHC) districts. Medical care was given in a state health system. PARTICIPANTS: A random sample (from the population register) of 15% of the population aged 25-74 (n = 1806). MAIN RESULTS: Among people reporting chronic pain 45.7% (compared with 29.8 of non-chronic pain persons, p < 0.05) consulted a physician and 7.2% (compared with 1.2%, p < 0.05) a physiotherapist during three months. Primary health care was the most frequent care provider. High pain intensity, aging, depression, ethnicity, and socioeconomic level had the greatest impact on physician consultations. Alternative care, used by 5.9%, was associated with high pain intensity and self care. Use of self care was influenced by high pain intensity, regular physical activity, and ethnicity. Alternative care and self care did not imply lower use of conventional health care. Women reporting chronic pain consumed more analgesics and sedatives than corresponding men. Besides female gender, high pain intensity, insomnia, physician consultation, social network, and self care action helped to explain medication with analgesics. Use of herbal remedies and ointments correlated to self care action, visit to an alternative therapist, high pain intensity, and socioeconomic level. CONCLUSIONS: The presence of chronic pain has an impressive impact on primary health care and medication. Various therapeutic actions are common and are partly overlapping. The use of health care among people with chronic pain depends above all on pain perception and intensity of pain but is also affected by ethnicity, age, socioeconomic level, and depressive symptoms. Among people with chronic pain use of analgesics is common in contrast with other types of pain relief (acupuncture, physiotherapy) suitable for treating chronic pain symptoms. 相似文献
999.
H Yang M Wirén J Larsson J Permert 《JPEN. Journal of parenteral and enteral nutrition》1999,23(4):207-212
BACKGROUND: To restore intestinal integrity after starvation and trauma, luminal nutrients are essential. Specific nutrients such as glutamine support mucosal proliferation and energy metabolism. The aim of this study was to compare effects of enteral formula vs specific amino acids on ornithine decarboxylase (ODC) activity and adenine nucleotide metabolism in jejunal mucosa. METHODS: Male Wistar rats (240 to 280 g) were starved for 48 hours and subjected to intestinal transection, gastrotomy, and jejunal instillation of 5mL nutrient solution. In the first experiment, standard enteral formula (EF) was compared with isonitrogenous formula supplemented with the glutamine precursor, alpha-ketoglutarate (alpha-KG). In a second experiment, 2% glutamine was compared with isonitrogenous ornithine alpha-KG, arginine alpha-KG, glycine and diluted standard enteral formula (EF), or saline. The ODC activity, adenosine triphosphates (ATP), and RNA and protein in the jejunal mucosa were analyzed 2 hours after surgery. RESULTS: The ODC peak in jejunal mucosa in animals treated with EF was higher than when supplemented with alpha-KG (p < .05). Compared with specific amino compounds, EF resulted in a significantly higher ODC peak and no differences were seen between the different specific amino acids. Differences seen in ATP or energy charge between the groups were not significant. CONCLUSIONS: Immediate postoperative enteral feeding by standard EF results in rapid increase of ODC activity. This response was attenuated when the enteral nutrition was supplemented with alpha-KG and was absent when isonitrogenous single amino acids were administered. We found no significant effects on ATP content in the small bowel mucosa by supplementing the diet with alpha-KG. 相似文献
1000.
L. Normén M. Johnsson H. Andersson Y. van Gameren P. Dutta 《European journal of nutrition》1999,38(2):84-89
Summary Plant sterols are known to have serum cholesterol lowering effects. A high dietary intake might therefore have a positive
impact on health. All food items of vegetable origin contain some amount of plant sterols. The aim of this study was to analyse
the plant sterol content of vegetables and fruits commonly consumed in Sweden, and to compare fresh and cooked samples of
the same items.
Altogether 20 different vegetables and 14 fruits were analysed. All vegetables and fruits were purchased in two shops in the
city of Gothenburg, Sweden. Lyophilization was performed within one month of the items being purchased. The samples were frozen
at −20 (C and analysed within six months, with a GLC method after acid hydrolysis, alkaline hydrolysis and silylation with
tri-methylsilylether. The acid hydrolysis was done in order to detect the fraction of glycosylated plant sterols, which are
split during boiling with HCl.
The median plant sterol content of vegetables was 14 (3.8–50) mg/100 g edible portion. The highest concentrations were found
in broccoli, Brussels sprouts, cauliflower and olives. The median plant sterol content of fruits was 16 (3–44) mg/100 g edible
portion. The highest concentrations were found in oranges and passion fruits.
The plant sterol concentrations were thus low in vegetables and fruits commonly consumed in Sweden. A serum cholesterol lowering
effect attributed to the plant sterols in vegetables and fruits would therefore be of limited significance.
Received: 25 September 1998, Accepted: 10 February 1999 相似文献