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71.
Lohi JJ Huttunen KH Lahtinen TM Kilpeläinen AA Muhli AA Leino TK 《Military medicine》2007,172(9):982-987
Caffeine has been suggested to act as a countermeasure against fatigue in military operations. In this randomized, double-blind, placebo-controlled study, the effect of caffeine on simulator flight performance was examined in 13 military pilots during 37 hours of sleep deprivation. Each subject performed a flight mission in simulator four times. The subjects received either a placebo (six subjects) or 200 mg of caffeine (seven subjects) 1 hour before the simulated flights. A moderate 200 mg intake of caffeine was associated with higher axillary temperatures, but it did not affect subjectively assessed sleepiness. Flight performance was similar in both groups during the four rounds flown under sleep deprivation. However, subjective evaluation of overall flight performance in the caffeine group tended to be too optimistic, indicating a potential flight safety problem. Based on our results, we do not recommend using caffeine pills in military flight operations. 相似文献
72.
Comparison of long-term outcome of laparoscopic and conventional nissen fundoplication: a prospective randomized study with an 11-year follow-up 总被引:3,自引:0,他引:3 下载免费PDF全文
OBJECTIVE: The aim of this study was to compare the long-term objective and subjective outcomes of laparoscopic and open Nissen fundoplication in a randomized clinical trial with an 11-year follow-up. SUMMARY BACKGROUND DATA: Laparoscopic Nissen fundoplication has become the method of choice in antireflux surgery, replacing its open counterpart despite the lack of long-term results from controlled clinical studies. METHODS: Between April 1992 and June 1995, 110 consecutive patients were randomized to either laparoscopic (LAP) or conventional (open) Nissen fundoplication. The objective long-term follow-up consisted of an upper gastrointestinal endoscopy and a clinical assessment; the subjective long-term outcome was investigated by personal interviews using a structured questionnaire. RESULTS: Forty-nine patients in the LAP group and 37 patients in the open group were available for evaluation. Late subjective results, including postoperative symptoms and evaluation of the surgical result, were similar in both groups. With the benefit of hindsight, 73.7% of the patients in the open group and 81.8% in the LAP group would again choose surgical treatment (P = 0.3042). In the LAP group, there were 5 (13.2%) partially or totally disrupted plications compared with the 14 (40.0%) disrupted plications in the open group (P = 0.0152). There were 10 incisional hernias in the open group compared with none in the LAP group (P < 0.001). CONCLUSIONS: At long-term follow-up, the open and LAP approaches for the Nissen fundoplication have similar long-term subjective symptomatic outcome despite the significantly higher incidence of incisional hernias and defective fundic wraps at endoscopy in the open group defining laparoscopic Nissen fundoplication as the procedure of choice in surgical management of gastroesophageal reflux disease. 相似文献
73.
The effects of temperature and sediment-chemical contact time on desorption and bioaccumulation of sediment-spiked (14)C-labelled 2,2',4,4'-tetrabromo diphenyl ether (BDE-47) and benzo(a)pyrene (BaP) were examined. Experiments were performed after 2 or 6 weeks and 23 or 24 months sediment-chemical contact time at 10 and 20 degrees C. Desorption was measured in a sediment-water suspension using Tenax extraction, and bioaccumulation was measured by exposing Lumbriculus variegatus (Oligochaeta) to BDE-47 and BaP-spiked sediments in a 10d kinetic study. Biota-sediment accumulation factors (BSAFs) ranged between 2.9 and 4.3 for BDE-47 and between 0.5 and 0.9 for BaP. Thus, temperature and aging had a minor effect on bioavailability estimates. On the other hand, the difference between the chemicals was clear and could not be interpreted solely by reference to the size of the desorbing fractions, although the rapidly desorbing fraction-revised estimate clearly reduced the difference. The remaining discrepancy may be related to methodological (Tenax extraction vs. worm exposure) and/or biological (digestive extraction) causes. However, the data support the role of diffusional forces in the bioavailability of sediment-associated organic contaminants. Therefore, desorption-revised bioavailability estimates would lead to more precise bioavailability estimates than the traditional sediment organic carbon-organisms' lipids-based equilibrium partitioning approach. 相似文献
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Lips I Dehnad H Kruger AB van Moorselaar J van der Heide U Battermann J van Vulpen M 《International journal of radiation oncology, biology, physics》2007,69(3):656-661
PURPOSE: To compare quality of life (QoL) after 70 Gy conformal radiotherapy with QoL after 76 Gy intensity-modulated radiotherapy (IMRT) in patients with locally advanced prostate carcinoma. METHODS AND MATERIALS: Seventy-eight patients with locally advanced prostate cancer were treated with 70 Gy three-field conformal radiotherapy, and 92 patients received 76 Gy IMRT with fiducial markers for position verification. Quality of life was measured by RAND-36, the European Organization for Research and Treatment of Cancer core questionnaire (EORTC QLQ-C30(+3)), and the prostate-specific EORTC QLQ-PR25, before radiotherapy (baseline) and 1 month and 6 months after treatment. Quality of life changes in time (baseline vs. 1 month and baseline vs. 6 months) of > or =10 points were considered clinically relevant. RESULTS: Differences between the treatment groups for QoL changes over time occurred in several QoL domains. The 76-Gy group revealed no significant deterioration in QoL compared with the 70-Gy group. The IMRT 76-Gy group even demonstrated a significantly better change in QoL from baseline to 1 month in several domains. The conformal 70-Gy group revealed temporary deterioration in pain, role functioning, and urinary symptoms; for the IMRT 76-Gy group a better QoL in terms of change in health existed after 1 month, which persisted after 6 months. For both treatment groups temporary deterioration in physical role restriction occurred after 1 month, and an improvement in emotional role restriction occurred after 6 months. Sexual activity was reduced after treatment for both groups and remained decreased after 6 months. CONCLUSIONS: Intensity-modulated radiotherapy and accurate position verification seem to provide a possibility to increase the radiation dose for prostate cancer without deterioration in QoL. 相似文献
76.
Huttunen Kristiina M. Terasaki Tetsuya Urtti Arto Montaser Ahmed B. Uchida Yasuo 《Pharmaceutical research》2022,39(7):1363-1392
Pharmaceutical Research - One of the major reasons why central nervous system (CNS)-drug development has been challenging in the past, is the barriers that prevent substances entering from the... 相似文献
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Mäki R Suihko E Rost S Heiskanen M Murtomaa M Lehto VP Ketolainen J 《Journal of pharmaceutical sciences》2007,96(2):438-447
In this study three model drugs (N-acetyl-D-glucosamine (NAG), anhydrous caffeine, and propranolol hydrochloride) were agglomerated with starch acetate (SA) by mixing the binary powders on a stainless steel (SS) plate. Agglomeration was induced by triboelectrification of the particles during mixing, and it was evaluated as a method to achieve controlled drug release rate. These agglomerates, mixed with different amounts of a disintegrant, were compressed into tablets whose dissolution characteristics were determined. Triboelectric measurements showed that when the drugs were in contact with SS, charges of the opposite polarity were generated to SA (+) and caffeine and NAG (-) promoting adhesion. Instead, propranolol HCl was charged with the same polarity as SA. SEM micrographs showed that smaller caffeine particles, in spite of their larger negative charge, agglomerated less efficiently with SA than larger NAG particles. This emphasizes the importance of particle size in the agglomeration process. Propranolol HCl did not form agglomerates with SA since their particle sizes and charges were identical. As a result, agglomeration of powders prior to tablet compression allows for modification and control of the release rate of the drugs from the SA matrix tablets as well as the tensile strength of the tablets. 相似文献
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