An experimentally supported, mathematical explanation of the gas chromatographic elution behaviour of the long-chain carbon members of the homologous series

By substituting the saturated vapour phase tension of the pure normal hydrocarbons described by the Clausius-Clapeyron law into the accepted expression of the specific retention volume (V_g,T), a theoretically coherent and relatively simple mathematical evidence of the elution behaviour of the homologous members has been deduced. It gives exponential retention time dependence on carbon number for isothermal, and nearly equidistant (i.e., approximately linear retention-time dependence on carbon number) elution for linear temperature programmed gas chromatographic runs. The final equations are in close correlation with the experimental results. Special emphasis is placed on the fact that a good approximation—not strict physical laws—have been found.     

Serial order short-term memory capacities and specific language impairment: No evidence for a causal association

This study re-explored the nature of verbal short-term memory (STM) deficits in children with specific language impairment (SLI), by distinguishing item and serial order STM processes. Recent studies have shown serial order STM capacity to be a critical determinant of language development, relative to item STM. In Experiment 1, 12 children with SLI, 12 age-matched children and 12 language-matched children were administered serial order recognition and reconstruction tasks. Experiment 2 assessed implicit serial learning abilities via a Hebb learning task. The SLI group showed impaired performance for the serial order reconstruction and recognition tasks, relative to language-matched and/or age-matched control groups. However, normal serial position effects were observed in all SLI children in the serial order reconstruction task, suggesting normal coding of serial position information. Similarly, performance on the Hebb serial learning task was at chronological age appropriate levels. Experiment 3 showed that the group differences observed for the serial order STM tasks in Experiment 1 disappeared when the SLI group was compared to a mental age-matched control group. Experiment 4 showed similar performance levels in the SLI group and the mental age-matched control group for a nonword recognition task assessing item STM capacities. This study shows that children with SLI have no specific impairments for serial order and item STM components but that poorer general cognitive efficiency is related to functional limitations in verbal STM tasks. The data are in line with limited information processing accounts of SLI.     

自拟消咳贴穴位贴敷治疗小儿反复呼吸道感染的临床研究

[目的 ]探讨自拟消咳贴穴位贴敷治疗小儿反复呼吸道感染 (RRI)的临床效果。 [方法 ]选择 15 0例RRI患儿 ,随机分为观察组和对照组 ,观察组在对因对症治疗基础上应用自拟消咳贴穴位贴敷 ,对照组采用对因对症治疗 ;另选 3 0例正常儿童 ,观察血浆内皮素 (ET -1)、一氧化氮 (NO)变化及临床疗效。 [结果 ]观察组治疗后血浆ET -1、NO含量明显下降 (P <0 .0 1) ,而对照组治疗前后则无统计学意义 ;观察组临床总有效率高于对照组 (P <0 .0 1) ,且每月发病次数及天数也明显降低。 [结论 ]应用自拟消咳贴穴位贴敷能有效地降低RRI患儿血浆ET -1、NO水平 ,从而提高临床疗效     

Investigation of melt agglomeration process with a hydrophobic binder in combination with sucrose stearate

The melt agglomeration process of lactose powder with hydrogenated cottonseed oil (HCO) as the hydrophobic meltable binder was investigated by studying the physicochemical properties of molten HCO modified by sucrose stearates S170, S770 and S1570. The size, size distribution, micromeritic and adhesion properties of agglomerates as well as surface tension, contact angle, viscosity and specific volume of molten HCO, with and without sucrose stearates, were examined. The viscosity, specific volume and surface tension of molten HCO were found to be modified to varying extents by sucrose stearates which are available in different HLB values and melt properties. The growth of melt agglomerates was promoted predominantly by an increase in viscosity, an increase in specific volume or a decrease in surface tension of the molten binding liquid. The agglomerate growth propensity was higher with an increase in inter-particulate binding strength, agglomerate surface wetness and extent of agglomerate consolidation which enhanced the liquid migration from agglomerate core to periphery leading to an increased surface plasticity for coalescence. The inclusion of high concentrations of completely meltable sucrose stearate S170 greatly induced the growth of agglomerates through increased specific volume and viscosity of the molten binding liquid. On the other hand, the inclusion of incompletely meltable sucrose stearates S770 and S1570 promoted the agglomeration mainly via the reduction in surface tension of the molten binding liquid with declining agglomerate growth propensity at high sucrose stearate concentrations. In addition to being an agglomeration modifier, sucrose stearate demonstrated anti-adherent property in melt agglomeration process. The properties of molten HCO and melt agglomerates were dependent on the type and concentration of sucrose stearate added.     

特异性神经元抗体对神经系统副肿瘤综合征筛检价值的研究

目的　探讨特异性神经元抗体 (尤其是抗 Hu抗体 )对国内人群神经系统副肿瘤综合征 (paraneoplasticsyndromesofnervoussystem ,PNSNS)筛检诊断的特异性和灵敏性。方法　采用免疫组织化学ABC法和Westernblot对 2 0例PNSNS和 12 0例非PNSNS患者的血清进行检测 ,并采用流行病学筛检公式计算出特异度和灵敏度。结果　PNSNS组和非PNSNS组ABC法阳性结果差异有统计学意义 (χ2 =33 4 5 ,P <0 0 1) ,特异性神经元抗体筛检诊断PNSNS的灵敏度为 95 % ,特异度为 72 5 % ;PNSNS组和非PNSNS组Westernblot法阳性率差异有统计学意义 (χ2 =117 12 ,P <0 0 1) ,抗 Hu抗体筛检诊断的PNSNS的灵敏度为 95 % ,特异度为 98 3%。结论　血清特异性神经元抗体 (尤其是抗 Hu抗体 )是国内人群中PNSNS患者较敏感和特异性的血清标志物 ,在神经元的免疫损伤中具有重要作用     

抗乙肝胎盘转移因子的特异免疫活性观察

本研究由ＨＢＶＭ－Ａｂ阳性胎盘提取的抗乙肝胎盘转移因子（ＰＳＴＦ）的特异免疫活性证明，经注射，小鼠外周血淋巴细胞明显增多，胸腺重量和指数亦显著增加，酯酶染色证明７５％属Ｔ－样淋巴细胞，２５％属Ｔｈｙ－样淋巴细胞，人白细胞或小鼠白细胞体外转移ＰＳＴＦ特异免疫活性、或豚鼠和小鼠体内转移ＰＳＴＦ特异免疫活性，再取其白细胞作白细胞粘附抑制、白细胞移动抑制、特异淋巴细胞转化、小鼠足掌注射和诱生γ－干扰素试验     

Self-inflicted specific pattern burns in psychiatric patients

Self-inflicted burns represent a major social and medical problem for society. Differences have been demonstrated between patients who attempt suicide and those who deliberately harm themselves without any intention of killing themselves. These self-inflicted injuries may resemble injuries that are intentionally inflicted by others and may require investigation by protective services. Little is known about these specific pattern burn injuries in psychiatric patients.     

Airway responses to antigen challenge in allergic rhinitis and allergic asthma

The density dependence of the maximum expiratory flow-volume curve, functional residual capacity (FRC), and specific airway conductance (SGaw) were determined before and during bronchial provocation with ragweed extract in 27 subjects with ragweed hypersensitivity and a history of either bronchial asthma (16 subjects) or allergic rhinitis (11 subjects). Mean baseline SGaw was significantly lower while mean volume of isoflow (Visov) and FrC were significantly higher in subjects with bronchial asthma. During antigen challenge, 10 of 16 subjects with bronchial asthma (63%) and five of 11 subjects with allergic rhinitis (45%) showed a greater than 35% decrease in SGaw ("reactors"): mean relative decreases in SGaw from baseline were 46% and 53%, respectively. The remaining subjects showed a less than 35% decrease in SGaw ("nonreactors") with mean relative decreases of 9% (allergic asthma) and 6% (allergic rhinitis). Mean Visov increased in all subjects with bronchial asthma and in eight of 11 subjects with allergic rhinitis. A significant increase in FRC (6%) was seen only in the "reactors" with bronchial asthma. Following antigen challenge, the beta adrenergic agonist, isoetharine, increased SGaw and decreased Visov. We conclude that in asymptomatic subjects with ragweed hypersensitivity, (1) central and peripheral airway function is more abnormal in subjects with bronchial asthma than in subjects with allergic rhinitis, (2) subjects of both groups show quantitatively and qualitatively comparable airway responses during antigen challenge with a decrease in SGaw or an increase in Visov, possibly representing increase in central and/or peripheral airflow resistance, respectively, (3) Visov may be a more sensitive indicator of airway response to antigen challenge than SGaw, and (4) the bronchodilator effects of a beta adrenergic agonist on antigen-induced bronchospasm are similar in both groups.     

Frequencies of background immunoglobulin-secreting cells in mice as a function if organ, age, and immune status

The influence of hereditary absence of thymus and spleen upon the numbers, organ, and class distribution of background immunoglobulin Ig-secreting cells was studied in mice by means of the protein-A plaque assay. In young adult BALB/c mice the spleen contained the largest number of Ig-secreting cells (about 0.5% ). The absolute number of Ig-secreting cells in the spleen was larger than the estimate for all lymph nodes together. Between 8 and 40 weeks of age, the number of Ig-secreting cells in spleen and lymph nodes increased by a factor of 3, maximally. In the same period, the number of Ig-secreting cells in the bone marrow, however, increased by a factor of 20, so that it became the major site of Ig synthesis. Hereditary absence of the spleen did hardly or not at all affect the number of Ig-secreting cells in the other lymphoid organs. However, the athymic state did affect the organ distribution. The most consistent finding was the decreased number of Ig-secreting cells in the Peyer's patches.The class distribution of Ig-secreting cells was found to be independent of the presence of the spleen, but did depend on the presence of the thymus. Athymic mice had a higher percentage of IgM-secreting cells and a lower percentage of IgA-secreting cells. The percentage of IgG₁- and IgG₂-secreting cells did not differ clearly between normal and athymic mice. Percent-wise, most IgM-secreting cells occurred in the spleen, whereas most IgG₁-, IgG₂-, and IgA-secreting cells occurred in the bone marrow, lymph nodes, and Peyer's patches.The specificity repertoire of the background Ig-secreting cells was tested by determining the frequencies of IgM-producing cells with specificity for a panel of six different antigens. These frequencies ranged from 1 in 85 for nitroiodophenyl(NIP)-conjugated sheep erythrocytes (SRBC) till 1 in 1500 for unconjugated SRBC and were found to be the same for the spleen of germ-free and specific pathogen-free (SPF) C3H mice, and for spleen, bone marrow, and thymus of SPF C3H mice.     

Dendritic spines in the visual cortex of the mouse: Introduction to a mathematical model

Summary The spines of apical dendrites of the layer V pyramidal cells of the area striata in the mouse represent a sequence of post-synaptic structures receiving a variety of contacts from terminal fibers derived fundamentally from short axon cells and superficial pyramidal cells. The study of Golgi preparations of mice 180 days old shows the existence of the most complicated terminal structures over portions of apical dendrites at the levels of layers III and IV. Observations on young mice reveals the terminations of the specific afferent fibers on the dendrites of short axon cells. A mathematical model which defines the distribution of spines along the apical dendrites is introduced. The principal equation of the model has been adjusted from the data processing of microscope countings through a series of programs written for an IBM 7070. The equation defines satisfactorily the different distributions of dendritic spines in mice 10–180 days old raised in normal conditions and in complete darkness. The equation defines also the distribution of dendritic spines in the visual cortex of mice enucleated at birth on one side, and the distribution along the apical dendrites of various cortical areas of the hamster, cat and man. The number of dendritic spines increases with the age of the subject and their distribution varies significantly according to the values of the parameters of the model.