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31.
Martin Døssing Steffen Groth Jørgen Vestbo Ole Lyngenbo 《International archives of occupational and environmental health》1990,62(3):209-212
Summary Among 701 Copenhagen plumbers we examined the lung function of 23 never smokers, who had removed asbestos insulation and intermittently been exposed to high levels of asbestos for about 25 years without being exposed to welding fume. The plumbers had significantly lower TLC, MEF25, MEF50, closing volume and closing capacity in comparison to 23 never smoking electricians without asbestos exposure. There was no reduction in TLCO. Pulmonary clearance of aerosolized 99mTc-DTPA was normal indicating that the asbestos had not induced increases in pulmonary epithelial permeability. However, in 11 of the 23 plumbers the 99m-Tc-DTPA ventilation scintigrams had a slightly irregular and spotty appearance, which together with the results of the lung function tests are suggestive of small airways' dysfunction. None of the subjects had symptoms or clinical signs of lung disease. 相似文献
32.
S. Örn P. L. Andersson L. Förlin M. Tysklind L. Norrgren 《Archives of environmental contamination and toxicology》1998,35(1):52-57
Zebrafish (Danio rerio) were orally exposed to a mixture of 20 PCBs in three different dose levels (0.008, 0.08, and 0.4 μg of each congener per
gram of freeze-dried chironomids). Generally, the PCBs accumulated in a dose-related manner. After 13 weeks of exposure body,
liver, and ovary weights, as well as the liver and ovary somatic index, were significantly lower in exposed groups. In addition,
the PCB mixture was an effective inducer of hepatic EROD activity. The reproduction study performed with exposed females and
unexposed males after 9 weeks revealed that median survival time for larvae was only 7.7 days in the high-dose group as compared
with 14 days in controls. Furthermore, egg production was reduced in all three groups exposed. No differences in hatching
frequency or median hatching time were recorded. Histologically, females in both the intermediate and high-dose groups contained
a reduced number of mature oocytes. The present study demonstrates that the potency of the mixture of selected PCBs induces
hepatic EROD activity and has a clearly negative effect on zebrafish reproduction.
Received: 7 May 1997/Accepted: 29 November 1997 相似文献
33.
International comparisons show that populations having a high consumption of fish experience low incidence of breast cancer. We compared death rates from breast cancer among socioeconomic groups in a prospective study of 533,276 Norwegian women aged 35–54 years who were followed from 1970 through 1985. Compared with the reference group (wives of unskilled workers) the fishermen's wives had a decreased risk of breast cancer with a relative risk (RR) of 0.67 (95% confidence interval [CI]=0.47–0.94) adjusted for age and the number of children. Among fishermen's wives who were parous, adjustment for age at first birth gave an RR of 0.62 (CI=0.43–0.91). This study supports the hypothesis that certain aspects of diet, i. e., fish consumption, may be associated with lower breast-cancer mortality.Drs Lund and Bønaa are with the Institute of Community Medicine, University of Tromsø, Tromsø, Norway. Address correspondence to Dr Lund, Institute of Community Medicine, University of Tromsø, N-9037 Tromsø, Norway. 相似文献
34.
35.
Jens Toft Birger Hesse Alan Rabøl Steen Carstensen Samir Ali 《European journal of nuclear medicine and molecular imaging》1997,24(4):409-414
Reference data files support the evaluation of myocardial perfusion single-photon emission tomography (SPET). The aim of this study was to create a large reference data base for technetium-99m sestamibi SPET, age and gender matched to the general patient population. One hundred and twenty-eight healthy volunteers (76 males and 52 females) with a likelihood of coronary artery disease of less than 5% underwent rest and maximal exercise99mTc-sestamibi SPET with a 2-day protocol and 180° elliptical rotation. The normalized activity values of99mTc-sestamibi in the inferior wall differed significantly between men and women. Age variations were found for men in the anterior wall. Normalized activity values in all four walls were strikingly similar during rest and stress. Our results suggest that the use of reference files in99mTc-sestamibi SPET requires a gender- and, for males, possibly an age-matched reference population. Different reference files at rest and during stress might not be necessary. 相似文献
36.
37.
OBJECTIVE: The purpose of this study was to obtain information about how patients perceive the health care delivered in an emergency department. SETTING: Patients who visited the ED at a Swedish university hospital during the daytime on Monday through Friday during a four-week period and were expected to be discharged from the ED after their visit were included in the study. Other criteria for participation were the patients' mental and physical abilities to fill out a questionnaire. STUDY DESIGN: One hundred eighty-seven patients (110 women and 77 men) classified as orthopedic, gynecologic, internal medical, surgical, or neurologic patients evaluated their perception of the health care delivered in the ED by filling out a questionnaire after arrival and before discharge. MEASUREMENTS AND MAIN RESULTS: The perceptions of the care received were on average quite positive. This was supported indirectly by the fact that scored pain, strength, calmness, and despair changed in a positive direction during the ED stay. However, a pattern of varying satisfaction appeared when the patients were dichotomized into three groups according to how they had perceived their first information on arrival. Fourteen percent of the patients had received exact information, 20% were partly informed, and 66% had received no information about what was going to happen to them next. Those who received the most information at the time of arrival at the ED were more satisfied with the general treatment (P less than .05), respect (P less than .01), and attitude (P less than .05) later shown by the staff as well as with the information given later (P less than .05) than were the patients who had received no information at all on arrival. The general evaluation of the ED was more positively (P less than .001) scored by the patients who received the most information (they were more satisfied) compared with the other two groups. CONCLUSION: The information given to patients on arrival at the ED may be important to a positive perception of the care given during their stay. 相似文献
38.
Anders Bj?rkman Peter J?rgsholm 《Nordisk plastikkirurgisk forening [and] Nordisk klubb for handkirurgi》2004,38(1):32-35
Although rupture of the extensor pollicis longus (EPL) tendon is a well-known complication of distal radial fractures, a number of patients rupture the EPL because of other conditions. We have retrospectively studied the aetiology of 27 ruptures of the EPL in 26 consecutive patients. Of 19 patients with injured wrists 12 had distal radial fractures, five had blunt trauma, and two had stab wounds that resulted in rupture. In the radial fractures operated on, the EPL rupture was caused by chafing against a dorsal plate (n = 2) or wear against the pins of an external fixator (n = 2). Six patients were taking steroids for systemic diseases and in two cases a local steroid injection was given just before the rupture. We conclude that previous injury is the most common cause of rupture of the EPL. but that rheumatoid arthritis or local or systemic steroids, or both, are also important aetiological factors. Seven patients had an iatrogenic cause for their rupture. 相似文献
39.
The effect of various thermal processes on the glycemic response to whole grain wheat products in humans and rats 总被引:1,自引:0,他引:1
J Holm B Hagander I Bj?rck A C Eliasson I Lundquist 《The Journal of nutrition》1989,119(11):1631-1638
The effects of different thermal processes used to produce ready-to-eat cereals on the glycemic response to whole grain wheat were investigated in rats. The metabolic response to drum dried flour, which constitutes the major component in instant gruel and porridge, was also studied in healthy human subjects. Boiled flour was used for comparison. The degree of starch gelatinization and rate of starch hydrolysis in vitro were also measured. Incompletely gelatinized steam flaked and dry autoclaved products were digested more slowly in vitro and elicited lower glucose responses in rats compared with completely gelatinized drum dried, extrusion cooked or boiled samples. The initial glycemic response in rats was closely related to the rate of starch hydrolysis in the pepsin/alpha-amylase assay (r = 0.91, P less than 0.04). When pepsin was omitted, no significant correlation was obtained. The peak glucose, insulin and C-peptide responses in humans after breakfast meals of porridge prepared from drum dried flour and from boiled flour were similar, whereas the rate of depression of the glucose curve was more rapid after consuming drum dried porridge. It is concluded that the glycemic response to wheat products is affected by the processing conditions used. The more severe the processing conditions, the more rapid the digestion of starch. 相似文献
40.
H Bell A Bj?rneboe B Eidsvoll K R Norum N Raknerud K Try Y Thomassen C A Drevon 《Alcohol and alcoholism (Oxford, Oxfordshire)》1992,27(1):39-46
The concentration of alpha-tocopherol was measured in liver biopsy specimens obtained from 83 patients with alcoholic and non-alcoholic liver diseases. The mean hepatic vitamin E content (as alpha-tocopherol) was significantly lower in 23 patients with alcoholic cirrhosis (17.6 +/- 12.1 nmol/mg wet weight liver), compared with 12 patients with normal liver histology (39.2 +/- 29.7 nmol/mg, P less than 0.01). The mean serum concentration of alpha-tocopherol was lower in patients with alcoholic cirrhosis (13.9 +/- 7.0 mumol/l) than in individuals with alcoholic fatty liver (21.3 +/- 9.3 mumol/l, P less than 0.01) and patients with normal liver histology (23.4 +/- 11.6 mumol/l, P less than 0.01). A decreased ratio of serum alpha-tocopherol/total serum lipids was also observed in patients with alcoholic cirrhosis, compared with patients with normal liver histology (P less than 0.05). There was a significant correlation between concentrations of alpha-tocopherol in liver and serum (r = 0.43, P less than 0.001). Furthermore, serum alpha-tocopherol correlated with retinol (r = 0.53, P less than 0.001), selenium (r = 0.45, P less than 0.001), and albumin (r = 0.37, P less than 0.001) in serum. We suggest that the reduced content of hepatic alpha-tocopherol observed in some patients may play a role in ethanol-induced lipid peroxidation. 相似文献