振动对小鼠体内磺胺嘧啶（SD）分布的影响

为了研究振动对生物体内物质的耗散作用，本文用药代动力学的方法在振动频率为２０Ｈｚ，加速度为１．１ｇ与５０Ｈｚ，４．４ｇ的条件下分别测试了小鼠体内血、肝与肾组织中磺胺啮咬（ＳＤ）在１至９小时内的分布，结果表明：２０Ｈｚ实验组血中ＳＤ浓度峰伍比对照组提前３小时，在振动１小时时，小鼠体内血、肝与肾组织中ＳＤ含量均比对照组高，但振动３小时至９小时内，其含量均比对照组低，从管道气栓体外模拟实验与本文的研究可得到启示：在上述频率与强度条件下，振动对生物体可能有促进血液循环的作用。     

Reproducibility and accuracy of a food frequency questionnaire used for diet intervention studies

The purpose of the present investigation was to determine whether altering the format of a food frequency questionnaire affected its accuracy and reproducibility. Three questionnaires were tested at one-month intervals. Questionnaire I contained 39 food items listed according to food categories. Questionnaire II contained 55 food items, presented according to the meal in which they were consumed. Questionnaire III contained 31 food items presented in a similar order to that in Questionnaire II. To determine the accuracy of the food frequency questionnaire, results were compared to those obtained from a simultaneously administered seven-day diet diary. Results from this study showed that food frequency questionnaires containing broad categories of food items presented in order of the meals in which they are consumed are the most reproducible. Highly reproducible results also can be obtained from seven-day diet diary, if data are calculated in terms of nutrients (i.e. carbohydrates, fats, proteins, etc.) and not specific food items. Finally, this study suggests that individuals more closely maintain their intake of nutrients, rather than specific food items.     

Some features of different motor units in human biceps brachii

Summary Use has been made of the method of selective leading-off of impulses from individual motor units at high isometric muscle tension, the maximum one including. Two types of motor units have been distinguished in m. biceps brachii in man on the basis of the dependence between the firing frequency and the level of the muscle tension. Characteristic of the first (tonic) type is the rise in the frequency at lower tensions and constant frequency at higher tensions. The second (phasic) type shows an approximately linear rise of the frequency with increase of tension. The tonic motor units are smaller in size, with lower threshold, they are less fatiquable and their transient pattern of firing depends on the rate of increase of tension. They contribute less to the growth of the muscle tension. The phasic motor units are bigger in size with higher threshold, more fatiguable, their transient pattern of firing does not depend on the rate of increase of tension. They contribute essentially to the growth of the muscle tension.     

The relationship between hippocampal EEG theta activity and locomotor behaviour in freely moving rats: effects of vigabatrin

The relationship between hippocampal electroencephalogram (EEG) theta activity and locomotor speed in both spontaneous and forced walking conditions was studied in rats after vigabatrin injection (500 mg/kg i.p.). Vigabatrin increased the percentage of time that rats spent being immobile. During spontaneous walking in the open field, the speed of locomotion was increased by vigabatrin, while theta peak frequency was decreased. Vigabatrin also reduced the theta peak frequency during forced (speed controlled) walking. There was only a weak positive correlation (r=0.22) between theta peak frequency and locomotor speed for the saline condition. Furthermore, vigabatrin abolishes the weak relationship between speed of locomotion and theta peak frequency. Vigabatrin and saline did not differ in the slope of the regression line, but showed different offset points at the theta peak frequency axis. Thus, other factors than speed of locomotion seem to be involved in determination of the theta peak frequency.     

Very fast rhythmic activity on scalp EEG associated with epileptic spasms

PURPOSE: Very fast activity was investigated on the ictal EEGs of epileptic spasms to elucidate the pathophysiology of West syndrome (WS) and related disorders from a novel point of view. METHODS: The traces of scalp ictal EEG of spasms temporally were expanded in 11 patients whose clinical diagnosis was symptomatic WS in six, cryptogenic WS in two, Aicardi syndrome in one, and symptomatic generalized epilepsy after WS in the remaining two. Time evolution of averaged power spectra of the ictal fast activity also was analyzed in each patient. RESULTS: Rhythmic gamma activity with frequency ranging from 50 to 100 Hz was detected in a total of 345 of 537 spasms. Fast activity was seen bilaterally in nine patients, was lateralized to one hemisphere in another, and appeared independently on each hemisphere in the remaining infant with Aicardi syndrome. Power spectra showed a clear peak corresponding to spasm-associated gamma rhythm, with frequency centering approximately 65 Hz and ranging from 51 to 98 Hz. The morphology and spectral characteristics of ictal gamma rhythm were completely different from those of muscle activity or alternating current (AC) artifacts. CONCLUSIONS: Spasm-associated gamma activity was clearly detected on the scalp. This observation may provide a clue to the pathophysiology of spasms.     

The action of 5-HT on calcium-dependent potassium channels and on the spinal locomotor network in lamprey is mediated by 5-HT1A-like receptors

5-HT has a powerful modulatory action on the firing properties of single neurons as well as on locomotor activity. In lamprey, 5-HT increases the neuronal firing frequency in spinal neurons by reducing the conductance in Ca²⁺-dependent K⁺ channels (K_Ca) underlying the slow afterhyperpolarization (sAHP), and it also lowers burst frequency of the spinal locomotor network. To elucidate which type of 5-HT receptor mediates these effects, different specific receptor agonists and antagonists were applied during intracellular current lamp recordings and during NMDA-induced fictive locomotion in the lamprey spinal cord in vitro preparation. The 5-HT_1A receptor agonist 8-OH-DPAT ((±)-8-hydroxy-dipropylaminotetralin hydrobromide), the 5-HT₁ receptor agonist 5-CT (5-car☐yamidotryptamine maleate) and the 5-HT₂ receptor agonist α-CH₃-5-HT (α-methylserotonin maleate) all reproduced the actions of 5-HT at both the cellular and the network levels. The effects of all agonists were completely or partially blocked by the 5-HT_1A and 5-HT₂ receptor antagonist spiperone (spiroperidol hydrochloride) while selective 5-HT₂ receptor antagonists were ineffective. The selective 5-HT_1A receptor antagonist S(−)-UH301 (S(−)-5-fluoro-8-hydroxy-dipropylaminotetralin hydrochloride) also counteracted the effect of 5-HT on the sAHP. 5-HT₃ and 5-HT₄ receptor agonists and antagonists were without effects. The intracellular coupling mechanism was not sensitive to pertussis toxin nor to the cAMP dependent protein kinase blocker (Rp)-cAMPS. These results indicate that the intracellular coupling mechanism is not likely to be due to a down regulation of adenylate cyclase activity or through a direct modulation of K⁺ channels, as is common for 5-HT₁ receptors. The present results taken together with previous data indicates that the receptor responsible for the effects of 5-HT on the sAHP, and on the locomotor pattern generator in lamprey shares certain features, but is not identical to the mammalian 5-HT_1A receptor.     

Dietary intake in the diabetes prevention program cohort: baseline and 1-year post randomization

PURPOSE: To describe usual dietary intake assessment at baseline and 1-year post-randomization in the ethnically diverse Diabetes Prevention Program cohort. METHODS: Participants were randomized to Lifestyle Modification, Metformin, or Placebo. Usual diet was assessed by a modified, previously validated food frequency interview. RESULTS: Complete data were available for 2934 subjects (90.7% of those randomized). Baseline median estimated energy intake was 7676 kJ/d (1828 kcal/d) and 8585 kJ/d (2044 kcal/d) for women and men, respectively. The median percent of energy from fat ranged from 30.6% for Asian American men to 37.5% for American Indian men and women. After 1 year among the Lifestyle group, the median change in total energy and percent energy from fat was -1897 kJ/d (-452 kcal/d) and -6.6%, respectively. For the Metformin and Placebo groups, change in median total energy was -1235 kJ/d (-294 kcal/d) and-1051 kJ/d (-250 kcal/d), respectively, and change in median percent energy from fat was -0.8% and-0.8%, respectively (p < 0.001 for differences between groups, adjusted for gender and ethnicity). CONCLUSIONS: One-year post-randomization, significant differences in dietary intake were observed in the Lifestyle compared with the Metformin or Placebo group, and these were consistent with the general intent of the DPP lifestyle modification intervention.     

双重围刺配合刺络拔罐治疗频次对急性带状疱疹疗效的影响

目的观察双重围刺配合刺络拔罐治疗急性期带状疱疹中治疗频次对临床疗效的影响。方法采用随机数字表法将100例急性期带状疱疹患者分为两组,每组50例。两组患者均口服盐酸伐昔洛韦和甲钴胺,联合双重围刺配合刺络拔罐治疗。试验组双重围刺法配合刺络拔罐的治疗频次为每日2次,对照组双重围刺法配合刺络拔罐的治疗频次为每日1次。对比观察两组患者治疗的临床疗效,止疱、结痂、脱痂时间,治疗前后疼痛视觉模拟量表(VAS)评分,疼痛缓解程度,每疗程末疼痛持续时间以及带状疱疹后遗神经痛发生率。结果试验组总有效率为98.0%,对照组总有效率为94.0%;两组治疗后VAS评分均较治疗前降低(P<0.05),且试验组低于对照组(P<0.05);试验组止疱、结痂、脱痂时间短于对照组(P<0.05);试验组疼痛缓解程度大于对照组(P<0.05);试验组前3个疗程末日疼痛持续时间均短于对照组(P<0.05);试验组后遗神经痛发生率为10.0%,对照组为18.0%。结论西药口服联合每日2次的双重围刺配合刺络拔罐对急性期带状疱疹患者可提高临床疗效,减轻患者疼痛持续时间及疼痛程度,缩短病程,疗效肯定。     

Listen carefully: The risk of error in spoken medication orders

Clinicians and patients often confuse drug names that sound alike. We conducted auditory perception experiments in the United States to assess the impact of similarity, familiarity, background noise and other factors on clinicians' (physicians, family pharmacists, nurses) and laypersons' ability to identify spoken drug names. We found that accuracy increased significantly as the signal-to-noise (S/N) ratio increased, as subjective familiarity with the name increased and as the national prescribing frequency of the name increased. For clinicians only, similarity to other drug names reduced identification accuracy, especially when the neighboring names were frequently prescribed. When one name was substituted for another, the substituted name was almost always a more frequently prescribed drug. Objectively measurable properties of drug names can be used to predict confusability. The magnitude of the noise and familiarity effects suggests that they may be important targets for intervention. We conclude that the ability of clinicians and lay people to identify spoken drug names is influenced by signal-to-noise ratio, subjective familiarity, prescribing frequency, and the similarity neighborhoods of drug names.