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71.
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   
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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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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.
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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PURPOSE: The purpose of this research was to study the incidence and outcome of flexor tendon injuries in pediatric patients. METHODS: A survey of flexor tendon repair in children less than 16 years of age was performed in the City of Helsinki during 2000-2005. A retrospective clinical outcome study of all consecutive 28 patients with 45 involved fingers treated in Children's Hospital was also performed at a mean 38 months (range 12-53 months) after surgery. Active motion program after multistrand tendon repair was used in 33 fingers, cast immobilization in 11 fingers, and elastic bands in 1 finger. Functional and cosmetic subjective result was evaluated by a visual analog scale (VAS, 0-100). Range of motion (ROM) of metacarpophalangeal (MCP) and interphalangeal (IP) joints were measured. Grip strength was recorded. Functional outcome methods of Buck-Gramcko, ASSH, Strickland, and distal interphalangeal joint (DIP) ROM methods were applied. RESULTS: The calculated annual incidence of finger flexor injury per child in Helsinki was 0.036 per 1000. There were no ruptures of the multistrand repairs with active motion program, but three 2-strand core sutures failed within 1 month of the repair. Mean functional and cosmetic VAS scores (all 28 patients) were 87 and 84. Mean ROM ratio of the DIP joint in zone 1 and 2 injuries was 60%, compared to 98% in zone 3 and 5 injuries. Ranges of motion of the proximal interphalangeal (PIP) and MCP joints were practically normal in all patients. There was a discrepancy among the functional outcome scores, with good and excellent results in all 45 fingers (Buck-Gramcko), in 39 fingers (ASSH), in 36 fingers (original Strickland), and in 32 fingers (DIP ROM). CONCLUSIONS: Flexor tendon injuries in children are rare. Both subjective and objective outcomes are generally good. Active motion program is an effective technique after multistrand flexor tendon repair at all levels in children. Range of motion of the DIP joint may be a more effective means of evaluating outcome in pediatric flexor tendon injuries. TYPE OF STUDY/LEVEL OF EVIDENCE: Therapeutic IV.  相似文献   
80.
Proton-coupled oligopeptide transporter PEPT1 facilitates the transport of dipeptides and peptoid drugs (including antibiotics) across the cell membranes of endothelial and epithelial cells. Substrate transport by the proton symport is driven by pH gradients, while the profile of pH sensitivity is regulated by a closely related protein. hPEPT1-RF. We investigated the genomic structure of hPEPT1 and hPEPT1-RF. Analysis of the high-throughput genomic sequence (HTGS) database revealed that hPEPT1 and hPEPT1-RF are splice variants encoded by the same gene located in chromosome 13, consisting of 24 exons. hPEPT1 is encoded by 23 exons and hPEPT1-RF by 6 exons. Coding sequences of hPEPT1-RF share 3 exons completely and 2 exons partially with hPEPT1. The genomic organization of hPEPT1 shows high similarity with its mouse orthologue. Exon-intron boundaries occur mostly in the loops connecting transmembrane segments (TMSs), suggesting a modular gene structure reflecting the TMS-loop repeat units in hPEPT1. The putative promoter region of hPEPT1 contains TATA boxes and GC-rich regions and a potential insulin responsive element.  相似文献   
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