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151.
B Sandstr?m A Cederblad B Stenquist H Andersson 《European journal of clinical nutrition》1990,44(10):705-708
Colonic retention of zinc and calcium was studied after installation during colonoscopy in 11 patients of a solution of 30 mumol zinc, 6.4 mmol calcium and 500 mumol inositol hexaphosphate (phytic acid) labelled with 65Zn and 47Ca. Whole-body retention of the radionuclide at day 13 was 1.0 +/- 1.0 per cent (mean +/- s.d.) for zinc and 4.0 +/- 2.9 per cent for calcium. The retention of zinc but not of calcium was lower than observed earlier under similar conditions from a solution not containing phytic acid and indicates formation of an indigestible complex between phytic acid and zinc. Addition of amino acids to the solution in 3 subjects did not seem to affect the retention of zinc and calcium. 相似文献
152.
The kinetics of inhaled methyl ethyl ketone (MEK) at a concentration of 200 ppm for four hours were studied in volunteers after swallowing ethanol at a dose of 0.8 g/kg. Ethanol was given either before or at the end of the exposure to MEK. The blood concentrations of MEK, 2-butanol, and 2,3-butanediol were monitored during and after the exposure. MEK concentrations in exhaled air and MEK and 2,3-butanediol concentrations in urine were also measured. Ethanol inhibited the primary oxidative metabolism of MEK and caused an increase in the blood concentrations of MEK and 2-butanol after ingestion. Ethanol ingestion, through higher blood MEK concentrations, also increased the elimination of MEK in the urine and exhaled air. Ethanol taken before exposure to MEK reduced the serum concentration of 2,3-butanediol initially but there was an increase about eight hours after the exposure. Urinary excretion of 2,3-butanediol followed the same pattern. Prior ingestion of ethanol thus seemed to interfere with the metabolism of 2,3-butanediol during and after exposure to MEK. 相似文献
153.
F. Röpke K. Klingebiel H. J. Hein R. Taute 《Archives of gynecology and obstetrics》1993,254(1-4):1159-1160
Schlu?folgerungen Aus der Me?wert-Verteilung der Grauwerte im Sonogramm lassen sich Kennwerte berechnen, die eine computergestützte sonographische
Reifebeurteilung der Plazenta erm?glichen. Allerdings sind die Verteilungsparameter (Median, Varianz, Schiefe, Exze?) abh?ngig
von den Ger?teparametern. Zuverl?ssiger ist die Berechnung von Kennwerten, die sich auf die strukturellen Eigenschaften des
Sonogramms beziehen. Bei den hier dargestellten Untersuchungen k?nnen Kennwerte für den Kontrast bzw. für die Ansammlung gleichartiger
Grauwerte um einen bestimmten Punkt die sonographische Beurteilung der Plazenta optimieren. Damit erweitern sich die M?glichkeiten
für die Zustandsdiagnostik der intrauterinen Lebensbedingungen. 相似文献
154.
Bojan Pajic Grigoris Pallas Gerding Heinrich Matthias Böhnke 《Albrecht von Graefes Archiv fur klinische und experimentelle Ophthalmologie》2006,244(1):22-27
Purpose It was the aim of this study to investigate the efficacy, longevity, and safety of a new ab interno intervention for the treatment
of primary open-angle glaucoma (POAG).
Methods The previously described method of radiofrequency-mediated “sclerothalamotomy ab interno” was applied in 53 eyes of consecutive
patients with POAG between April 2002 and July 2002. Average preoperative intraocular pressure (IOP) was 25.6±2.3 mmHg (range
18–48 mmHg). Sclerothalamotomies were carried out with a custom-made high-frequency dissection 19 G probe (tip 0.3×1 mm) applying
bipolar current with a frequency of 500 kHz (tip temperature 130°C).
Results After a follow-up period of 24 months, the average IOP was 15.0±1.6 mmHg (range 11–20 mmHg) (p<0.005). The average number of topical agents was 2.6±1.0 (range 1–5) preoperatively. Twenty-four months after surgery such
agents were used in only five (9.6%) eyes and the average was 0.21±0.53 (range 0–2). Transient IOP elevation was observed
in 12 of 53 eyes (22.6%) postoperatively. In all cases elevated IOP could efficiently be controlled with topical medication.
In general, IOP dropped continuously over the course of the 6 months following surgery and then remained constant.
Conclusions This study indicates that sclerothalamotomy ab interno is a safe and efficient surgical method for the treatment of POAG.
Long-term results clearly demonstrate the longevity of IOP reduction. 相似文献
155.
Specific effects of fermentable carbohydrates on blood urea flux and ammonia absorption in the rat cecum 总被引:1,自引:0,他引:1
These studies were conducted to determine to what extent dietary fibers, or related compounds such as lactulose or amylomaize starch, alter the flux of blood urea to the cecum and cecal absorption of ammonia in the rat. Cecal weight and pH values were not different among rats fed diets containing 10% lactulose, pectin or guar gum, or 25% amylomaize starch. However, the cecal wall weight was markedly higher with lactulose feeding than with the other polysaccharides, whereas volatile fatty acid concentrations were lower with lactulose. The fiber diets depressed cecal ammonia, particularly in the case of the amylomaize starch diet, whereas the lactulose diet enhanced the concentration of ammonia. Owing to cecal enlargement and enhanced blood flow, the diets containing fermentable carbohydrates promoted a higher flux of urea to the cecum and also higher ammonia absorption in spite of low concentrations of ammonia in the cecum. Lactulose led to particularly high transfer of urea and absorption of ammonia. High blood urea in rats fed a 50% casein diet led to a very high flux of urea to the cecum and, hence, to high ammonia absorption. The presence of polysaccharides amplified the flux of urea and ammonia in the cecum. This study suggests that oligosaccharides such as lactulose, although very effective for the acidification of the contents of the large intestine, may enhance cecal ammonia and its absorption. Polysaccharides such as amylomaize starch might show greater efficiency for lowering ammonia concentrations in the large intestine. 相似文献
156.
157.
Prof. Dr. E. Minar B. Pokrajac R. Wolfram A. Budinsky C. Kirisits R. Pötter 《Gef?sschirurgie》2003,8(2):75-84
The therapeutic concept of irradiation of the vessel wall for prevention of restenosis after endovascular procedures is based on increasing knowledge about the pathophysiology of the process leading to restenosis. There is until now only a limited number of studies concerning the use of brachytherapy (BT) in the peripheral circulation, which is in contrast to the already large experience in the coronary circulation. In the peripheral trials the radiation dose was administered by a remote afterloader using a gamma source. According to the available data, vascular BT is a promising technology with the potential to reduce the restenosis rate. The Vienna-2-Trial was the first randomised study to demonstrate the efficacy of endovascular BT for prophylaxis of restenosis after femoropopliteal percutaneous transluminal angioplasty. However, we have to await further supportive data from ongoing clinical trials before definitive recommendations can be given. Currently, endovascular BT seems already justified in patients with recurrent interventions or after long-segment femoropopliteal angioplasty because of the high risk of restenosis in these patients. The next years will demonstrate the ultimate role of endovascular BT in comparison to the rapidly evolving field of drug-eluting stents. 相似文献
158.
159.
G. Ransmayr W. Poewe S. Plörer F. Gerstenbrand K. Leidlmair U. Mayr 《Journal of neural transmission (Vienna, Austria : 1996)》1986,67(1-2):1-14
Summary Forty-four Parkinson patients (19 patients of the rigid-akinetic type, 13, of the rigid-akinetic-tremor type, and 12, of the tremor type) were included in a study in order to analyse correlations of the expression of the motor symptoms tremor, rigidity, akinesia, with other clinical parameters, computertomographic aspect of brain atrophy and psychometrically assessed cognitive parameters. Rigidity and akinesia are significantly positively correlated with the severity of motor dysability, stage of the disease, and brain atrophy, as is akinesia with a history of pharmacotoxic psychosis. Tremor is significantly negatively correlated with motor dysability, stage of the disease, and history of pharmacotoxic psychosis. Akinesia is correlated with visuomotor dysfunction (tested with Bender Gestalt Test) and rigidity with the depression score (Zung scale). The tremor type is favorable, the rigid-akinetic type unfavorable with respect to motor disability and psychosis. 相似文献
160.
K. H. Vogelberg M. Mühl M. Köhler 《Journal of molecular medicine (Berlin, Germany)》1987,65(15):713-718
Summary Seventy-five diabetic and 40 nondiabetic subjects who where suffering from peripheral vascular disease were studied in order to determine whether the degree of the severity of their disease can be better calculated by Doppler ultrasound examinations of the peak velocity than by the systolic pressure of the peripheral bloodstream. In 46 examinations of normal controls the mean value of the peak velocity was 13.3±3.3 cm/s with a standard deviation of 15.4%±13.2% on one day and 16.1%±15.9% on different days. Considering patients with or without diabetes mellitus the velocity was significantly decreased in correlation to an increasing degree of severity of the vascular disease (P<0.001); however, the decrease was lower in diabetic than in nondiabetic subjects (6.9±2.8 vs 4.6±6.2,P<0.05). The systolic pressure hardly decreased, but remained higher in all stages of peripheral vascular disease of diabetics than in the nondiabetic subject (P<0.05 toP<0.005). There was a significant decrease of the systolic pressure only in diabetic subjects with the most advanced degree of the disease, i.e. stage IV (P<0.05).It is concluded from this study that Doppler ultrasound measurements of the peak velocity of the peripheral bloodstream are a useful parameter to calculate the degree of severity of the peripheral vascular disease. In addition, it is concluded than peak velocity is an even better prognostic indicator of peripheral vascular disease than is measurement of the systolic blood pressure at the feet.
Abkürzungen AVK periphere arterielle Verschlußkrankheit - USDI Ultraschall-Doppler-Index - MSBG maximale Blutströmungsgeschwindigkeit - HFV Herzfrequenzvariation 相似文献
Abkürzungen AVK periphere arterielle Verschlußkrankheit - USDI Ultraschall-Doppler-Index - MSBG maximale Blutströmungsgeschwindigkeit - HFV Herzfrequenzvariation 相似文献