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31.
PURPOSE: The objective of this study was to estimate tobacco use prevalence among the Amish in Holmes County, Ohio, using both self-report and a biochemical marker of nicotine exposure. METHODS: Amish adults (n=134) were interviewed as part of a lifestyle study. Self-reported tobacco use was measured using standardized questions, and cotinine was measured from a saliva sample. The prevalence of smoking, total tobacco use, and misclassification were estimated separately by gender, and then compared to 2 non-Amish groups. One group was selected from 2 counties contained within the Holmes County Amish settlement (n=154) and the other was representative of non-Hispanic whites in the United States (n=4,099). FINDINGS: No Amish women reported current tobacco use and only 2 reported former use. This was significantly different (P<.0001) from the patterns observed among non-Amish in the settlement counties (15.7%) and US white (23.3%) women. The prevalence of tobacco use among Amish men was 17.6% and this was significantly lower than estimates from non-Amish in the settlement counties (38.8%, P=.04) and US white (32.2%, P=.005) men. No Amish women and only 2 Amish men underreported tobacco use and misclassification was similar in the comparison groups. CONCLUSIONS: Tobacco use is significantly lower among adults in the largest Amish settlement in the world compared to their non-Amish neighbors in Appalachia Ohio and US whites. A strength of this study is that self report was verified with a marker of nicotine, a critical measure to include in any study conducted in a group that stigmatizes tobacco use.  相似文献   
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Summary The afferent fibres to the ventroposterolateral nucleus (VPL) of the contralateral thalamus from neurons in the dorsal column nuclei (DCN) and the lateral cervical nucleus (LCN) were labelled by anterograde transport of wheat germ agglutinin-horseradish peroxidase conjugate and subsequent histochemical processing with tetramethyl benzidine. In accordance with the results of previous light microscopical studies using the degeneration method or autoradiographic tracing technique, the distribution of the afferents from the DCN and LCN in the VPL differed considerably. Thus the DCN terminals, which were calculated to constitute about 7–8% of the total number of boutons in the VPL, were found throughout the entire VPL, whereas the LCN terminals were mainly located in its dorsal and dorsolateral parts, where they made up about 1% of the total number of boutons. However, the morphology and synaptic organization of the terminals from the DCN and LCN were virtually identical. Thus the synaptic terminals of the two afferent pathways seemed to be represented by large boutons of a similar type, which had large, slightly oval and loosely packed synaptic vesicles and contained numerous mitochondria. Both DCN and LCN terminals synapsed preferentially on medium-sized to large dendrites, but were also presynaptic to other vesicle-containing profiles, probably of internuncial origin, which in turn were in synaptic contact with the same dendrites as the labelled ones.It is suggested that the differences in physiological properties between the somatosensory information that is transmitted to the somatosensory cortex via the dorsal column-medial lemniscus pathway and the spino-cervico-thalamic tract do not seem to have a counterpart in differences in the synaptic organization of their relay in the VPL.  相似文献   
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Modalen AO  Quiding H  Frey J  Westman L  Lindahl S 《Anesthesia and analgesia》2005,100(3):713-7, table of contents
In animal models frakefamide (FF) is a potent analgesic that acts as a peripheral active mu-selective receptor agonist. In this double-blind, randomized, double dummy four-way crossover study in 12 healthy male subjects, we investigated the effects on resting ventilation of FF and 2 dose levels of morphine compared with placebo. Each drug was infused for 6 h. The subjects received 1.22 mg/kg FF, 0.43 mg/kg morphine (M-large), and 0.11 mg/kg morphine (M-small). Sodium chloride 9 mg/mL was used as placebo. Ventilation was measured by pneumotachography and inline capnography. Blood was collected and plasma concentrations of FF and morphine and its metabolites were analyzed. Within 15 min after administration of FF all subjects complained of a transient myalgia, which disappeared within 30 min. At target measurement (335 min), there were no differences in tidal volume among the groups. Respiratory rates were, however, slower in the two M-groups (P < 0.05 in M-small and P < 0.001 in M-large) compared with FF and placebo. Minute volume was significantly less in the M-large group compared with the FF (P < 0.01) and placebo (P < 0.01) groups. This difference was reflected by an elevated ETco(2) in the M-large group (P < 0.01). We conclude that, during resting ventilation, FF, unlike morphine, did not cause central respiratory depression. This suggests that FF has only peripheral mu-opioid agonist activity in humans.  相似文献   
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Lasser  EC; Lang  JH; Lyon  SG; Hamblin  AE; Howard  MM 《Radiology》1981,140(1):11-15
An in vitro is described that attempts to detect patients with a potential for adverse systemic reactions to contrast material. This test involves measuring the rate of conversion of prekallikrein to kallikrein under certain standard conditions. In a preliminary retrospective study, the test could be used to identify such patients with a sensitivity of 88%, a specificity of 82%, and a predictive value of 79%.  相似文献   
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