一种可扩展的XPath查询最小化算法框架

XPath是XML的基本查询语言,XPath查询最小化对于提高XML数据库的查询性能具有重要意义.但是,由于XPath查询最小化是一个coNP完备问题,大部分已有的算法局限于处理简单的XPath片段.本文从一个新的角度入手,综合考虑完备性和高效性,提出了一个新的查询最小化框架,与已有算法"面向结点",即逐个删除冗余结点的解决思路不同,本文提出"面向树模式"的方式,即通过计算树模式的自同态映射,寻找目标结点集最小的自同态映射,进而求解最小等价查询树的方法.该方法具有较高的效率,而且在--Z..情况下是完备的,尤其是可以进一步扩展到更复杂的XPath片段.本文以此框架为基础,给出一个可以计算复杂查询模式的算法.     

孟根乌森乌日乐对小鼠的急性毒性研究

目的：了解孟根乌森乌日乐的急性毒性作用剂量及给药后的急性毒性反应和死亡分布情况,确定孟根乌森乌日乐的半数致死量（ LD50）。方法用孔氏综合法（改进寇氏法）分为14．30,9．28,6．04,3．92,2．55,1．66 g? kg－16个剂量组,以0．4 mL／10 g的量灌胃给药1次。实验后观察14 d,记录体重变化及不良反应情况。结果孟根乌森乌日乐小鼠半数致死量为5．1597 g? kg－1（95％CI：3．6652～7．2637 g? kg－1）。14 d内未出现明显不良反应症状且体重有增长趋势。结论孟根乌森乌日乐的急性毒性实验的半数致死量为临床用药量的100倍,提示单次口服较为安全。     

淋巴靶向制剂——吸附抗癌药毫微粒活性炭的研究进展

目的介绍新型淋巴靶向制剂———吸附抗癌药毫微粒活性炭的研究进展。方法依据近年来的文献 ,对活性炭的制备工艺及体内外性质等方面进行了综述。结果活性炭具有很强的吸附功能 ,普通市售活性炭仅用作脱色、吸附热原与除味等。以微粒球磨机为粉碎器械 ,可加工制备粒径达1 0 0nm左右的纳米炭微粒 ,具有优越的淋巴趋向性。结论吸附抗癌药毫微粒活性炭在临床治疗癌症方面具有良好的运用前景     

德都红花-7味散原药方与优化方对肝纤维化大鼠Ⅰ,Ⅲ型胶原mRNA表达的影响

目的:探讨德都红花-7味散原药方及优化方对肝纤维化大鼠Ⅰ,Ⅲ型胶原mRNA表达的影响。方法:40只Wistar大鼠分为正常组、模型组、阳性药组、原药组、优化组。大鼠ip 30%CCl4橄榄油溶液建立肝纤维化模型。同时1次/日ig给药,阳性药组给予秋水仙碱片0.4 mg·kg-1;原药组给予德都红花-7味散0.6 g·kg-1;优化组给予德都红花-7味散优化方0.6 g·kg-1。连续40 d后处死大鼠。取肝脏天狼星红染色,观察肝组织纤维化程度和Ⅰ,Ⅲ型胶原分型。酶联免疫吸附法(ELISA)检测肝组织匀浆Ⅲ型前胶原和Ⅳ型胶原,层粘连蛋白(LN),透明质酸(HA)含量。实时荧光定量PCR法检测Ⅰ型胶原,Ⅲ型胶原mRNA表达变化。结果:天狼星红染色模型组Ⅰ,Ⅲ型胶原纤维较正常组增多,阳性药组、原药组、优化组Ⅰ,Ⅲ型胶原纤维较模型组减少。与正常组比较,酶联免疫法检测模型组Ⅳ型胶原,HA含量升高(P0.05)。与模型组比较,阳性药组、原药组、优化组Ⅲ型前胶原、Ⅳ型胶原、HA含量明显降低(P0.05)。实时荧光定量PCR法检测模型组Ⅰ型胶原mRNA和Ⅲ型胶原mRNA表达较正常组上调(P0.01)。阳性药组、原药组、优化组Ⅰ型胶原mRNA和Ⅲ型胶原mRNA表达较模型组下调(P0.01)。原药组、优化组Ⅰ型胶原mRNA表达较阳性药组下调(P0.05)。优化组Ⅰ型胶原mRNA表达较原药组下调(P0.05)。结论:德都红花-7味散原药方与优化方是通过抑制Ⅰ型胶原mRNA和Ⅲ型胶原mRNA的转录,达到阻断或延缓肝纤维化的发生发展,德都红花-7味散优化方优于原药方。     

The effects of perinatal diazepam exposure on stress-induced activation of the mesotelencephalic dopamine system

The effects of perinatal diazepam exposure of rats on stress-induced metabolic activation of the mesotelencephalic dopamine (DA) system were examined. Footshock stress parameters were selected such that DA turnover was increased in the prefrontal cortex and certain mesolimbic dopaminergic regions; a stress-induced activation of striatum was not observed. Perinatal treatment with the anxiolytic benzodiazepine diazepam (days E8 through the first week after gestation) did not alter basal dopamine turnover in the prefrontal cortex or striatum, or in any of the mesolimbic sites examined except for the nucleus accumbens and ventral tegmental area (in which turnover was decreased). However, perinatal exposure to diazepam significantly reduced the magnitude of the stress-elicited increase in prefrontal cortical dopamine turnover, and conversely resulted in a stress-induced enhancement of turnover in the striatum. These data suggest that although perinatal exposure to diazepam may alter basal dopaminergic function in some regions, certain enduring changes in dopamine function in other mesotelencephalic DA sites are revealed only under conditions that result in perturbation of central dopamine neurons, such as environmental stress. These data also suggest that perinatal benzodiazepine exposure may be reflected in the adult in a decreased ability to cope with stress.     

Do endogenous excitatory amino acids influence striatal dopamine release?

In vivo microdialysis techniques were used to examine whether endogenous excitatory amino acids exert a tonic facilitatory influence on striatal dopamine release. Local application of NMDA and non-NMDA antagonists at 10 microM was without an effect on basal dopamine release while 100 microM and 1 mM of these drugs significantly enhanced the release. Our findings do not support the idea that excitatory amino acids have a tonic excitatory effect on striatal dopamine release.     

Cervicogenic headache

Eleven female patients with cervicogenic headache (mean age, 43 years; range, 25-59 years) have been examined with the pupillometer. The pupillary diameter was examined in the basal state (that is, the status before pharmacologic stimulation) and after topically administered tyramine (2%), phenylephrine (1%), and hydroxyamphetamine (1%). A total of 51 tests were performed, 35 in the asymptomatic period and 16 during pain attacks. In a control group consisting of 26 age-matched women a total of 39 tests were carried out. Before pharmacologic stimulation (that is, in the "basal state") the pupils were smaller in the asymptomatic (pain-free) period than during pain attacks in the patients and also as compared with that of control individuals. The anisocoria (the difference in pupillary size in the same individual) observed was not significantly different between the patient group and control individuals either in the basal state (before pharmacologic stimulation) or after pharmacologic stimulation. The mydriasis resulting from the instillation of the three sympathicomimetic drugs was symmetrical in both controls and patients both during and between the pain attacks. This finding is in clear contrast to what is found in cluster headache, in which there is a "Horner-like" syndrome on the symptomatic side. These two headaches thus seem to differ essentially with regard to this variable.     

Clinical measurement of swallowing in health and in neurogenic dysphagia

We studied clinical features potentially related to dysphagia and three indices from a timed test of swallowing--average volume per swallow (ml), average time (s) per swallow and swallowing capacity (ml/s)--in 181 screened healthy adults and 30 patients with motor neurone disease (MND). In healthy adults, age, sex and height accounted for 44.3% and 55.6% of the variance of log average volume per swallow and log swallowing capacity, respectively. Symptoms and signs were more prevalent in the MND group and were associated with reduced swallowing capacity and reduced average volume per swallow; repeatability studies on these two indices in both groups showed that the median difference between the mean of two recordings on successive days and the mean of all recordings (6-15 over 3 days) was < 5% (maximum third quartile 12.8%, indices expressed as percent predicted according to age and sex). Using this simple bedside test, swallowing function can be quantified on a ratio scale and expressed as percent of that predicted by age and sex; such information may improve the predictive value of clinical assessment and provides a practical way of monitoring change in patients with dysphagia.