306名大学生错失恐惧与社交媒体倦怠的关系:睡眠质量和负性情绪的链式中介作用

目的 探讨大学生睡眠质量、负性情绪在错失恐惧与社交媒体倦怠间的中介作用。 方法 采用错失恐惧量表、社交媒体倦怠量表、匹兹堡睡眠质量指数量表、抑郁-焦虑-压力量表简体中文版对306名大学生进行调查。 结果 错失恐惧、社交媒体倦怠、睡眠质量和负性情绪之间呈两两正相关;错失恐惧能正向预测社交媒体倦怠;睡眠质量和负性情绪在错失恐惧和社交媒体倦怠之间起单独中介作用,且睡眠质量和负性情绪在错失恐惧与社交媒体倦怠之间起链式中介作用,负性情绪各维度效应皆成立。 结论 睡眠质量和负性情绪能够为错失恐惧对社交媒体倦怠的影响提供一个解释机制,大学生的错失恐惧既可以直接影响其社交媒体倦怠水平,也可以通过睡眠质量、负性情绪的独立中介效应以及睡眠质量-负性情绪的链式中介效应间接影响。     

Effects of convergent strabismus on spatio-temporal response properties of neurons in cat area 18

Summary Single-cell recording experiments were carried out to determine whether rearing kittens with surgically induced convergent strabismus (esotropia) alters the development of receptive field (RF) properties of neurons in area 18. In agreement with previous work on kittens with divergent strabismus (exotropia), there was a marked loss of binocularly driven cells in area 18 of esotropic cats. In contrast to the striate cortex of strabismic cats, the spatial properties of area 18 neurons, including receptive-field size and spatial frequency tuning, did not differ from those in normal controls. On the other hand, we found that contrast thresholds, measured at an optimal spatial frequency, were significantly elevated, and that the contrast gain in many cells was reduced in strabismic cats. These deficits were observed in both eyes, though the cells dominated by the deviating eye had a lower response amplitude at all contrasts. Furthermore, temporal frequency tuning curves were abnormal in strabismic cats in that the optimal frequencies and temporal resolutions were shifted to lower values. These effects were also bilateral. Velocity tuning, measured with a high-contrast bar stimulus, revealed that area 18 neurons in strabismic cats were unable to respond to very high velocities compared to normals. This reduced response was more severe when measured with the deviating eye in spite of the bilateral nature of the deficit. Finally, latencies to electrical stimulation of the optic chiasm or the optic radiation were significantly longer in strabismic cats. The magnitude of these effects was virtually the same for both eyes. From these observations, we conclude that the temporal properties of area 18 neurons, particularly the cells abilities to follow fast temporal modulations, are affected by raising kittens with surgically induced convergent strabismus.     

Use of serum-free hormonally defined media to evaluate the effects of growth factors and inhibitors on proliferation of estrogen-responsive mammary and pituitary tumor cells in culture

Summary Serum-free defined media have been developed for assay of the mitogenic effects of growth factors on human MCF-7, human T-47D, and mouse COMMA-D mammary cells as well as for identification of mitogens and inhibitors of GH₄C₁ rat pituitary tumor cell growth. These lines were shown to grow in vivo in response to a variety of hormones including estrogens and thyroid hormones. With mammary cells, complete hormonally and nutritionally defined media were established that supported continuous passage at 50 to 90% of the serum stimulated rate. The strategy used to measure mitogens for mammary cells was to identify nutritional conditions where the growth rate was reduced greatly without impairing the response to picomolar to nanomolar concentration of growth factors. The effects of polypeptide growth factors and tissue extracts were estimated by their addition to basal medium and measuring cell number increases or labeled thymidine incorporation into DNA. In a variation of this methodology, the MTW9/PL2 rat mammary cells were used to identify secreted autocrine growth factors; nutritionally defined conditions were sought for growth of these rat cells in the complete absence of exogenous growth factors. The factors secreted into the medium were detected by bioassays with COMMA-D or MCF-7 mammary cell lines. The effects of growth factors-inhibitors on pituitary cells were measured by a related method; the GH₄C₁ cells were grown at less than optimal rates in a defined medium designated TRM-1. Addition of mitogens to TRM-1 stimulated pituitary cell growth whereas addition of inhibitors caused reduced levels of growth. The methods described in this report offer new means of assaying growth factors-inhibitors for a range of mammary and pituitary tumor cells.     

Diagnosis of iodinated contrast media hypersensitivity: results of a 6-year period

Background Iodinated contrast media (ICM) hypersensitivity reactions represent a serious problem. Very few clinical data concerning systematic skin testing to ICM are available. Objective To evaluate the utility of ICM skin testing in patients with ICM hypersensitivity. Material and methods All patients referred over a 6‐year period for ICM hypersensitivity past reactions were skin tested for (a) the implicated ICM, or (b) a set of ICM if they were positive for the implicated ICM or if its name was unknown. Results Forty‐four patients, with a median age of 56 years, were studied (15 males, 29 females). The ICM skin tests were positive in 10 patients (23%): one had a positive skin prick test, seven an immediate positive intradermal test (IDT) and two a delayed positive IDT. Skin tests were more often positive in patients with immediate (9/32) as compared with those with non‐immediate reactions (1/11). The time interval between the reaction and skin testing was shorter for those patients with an immediate ICM reaction and a positive skin test result (3 months [2.5–174.0]) as compared with those with an immediate ICM reaction and a negative skin test (48 months [6.8–159.0]), (P<0.05). Respiratory allergy was more frequent in the positive group (6/10 vs. 7/34, P<0.05). Conclusions Skin tests with ICM are positive in a subgroup of patients with ICM hypersensitivity and may play an important role in the diagnosis of ICM allergy.     

超声波介导的基因输送技术

近年来超声波介导的基因输送技术由于其相对安全性和操作上的简单得到关注。本文对超声波导致的声致穿孔的机制,空化核的作用——增强基因输送的效率,以及细胞和在体基因输送效率作了综述,讨论了超声波介导的基因输送效率的影响因素。此方法充满希望并且载药的空泡可以作为一种新型药物载体在超声作用下实现药物的靶向输送     

Lymphoid and non-lymphoid cells in the adenoid of children with otitis media with effusion: a comparative study

We characterized on immuno- and enzymecytochemical level the lymphoid and non-lymphoid cells in the adenoid of children with upper respiratory tract infections (URI) and otitis media with effusion (OME) and compared these with the adenoid of children with URI without OME and with the adenoid of 'healthy' children and adults. Besides macrophages and dendritic cells we also showed the presence of MHC class II positive, ciliated, epithelial cells. These non-lymphoid cells were present in all adenoids. However, their number was less than 1% of all cells. We found no difference in lymphocyte subsets from children with URI + OME compared with those from children with URI alone. These two groups showed a significant decrease of CD8-positive (suppressor/cytotoxic) cells and a slight increase in CD22-positive B cells in comparison to 'healthy' children. No difference was found in percentages of CD4-positive (helper/inducer) cells. The localization of the lymphoid subsets in adenoids of children with URI and/or OME did not differ from those of 'healthy' children and adults.     

Binocular suppression in cortical neurons

Summary Dichoptic presentation of patterns similar in shape but of very different contrast results in the perception of only the high contrast pattern (binocular suppression). When recording from binocular neurons of the cat visual cortex, we have found an effect which is strikingly similar to this perceptual phenomenon. If a high and a low contrast grating are presented simultaneously, one to each eye, the cell's response to the low contrast stimulus is suppressed.     

Pontine veins. MRI cross-sectional anatomy

Summary The pons is covered by a rich venous network offering numerous vascular landmarks in MRI and during surgery. We present an original study of the veins as they appear on MR multiplanar scans after gadolinium IV injection. This prospective study is based on 40 consecutive patients with normal posterior fossa structures. One of the major venous collectors follows the pons: the superior petrosal v. was identified on MRI in 95% of our cases. Its hooklike extremity drains into the superior petrosal sinus. The inferior petrosal v. was never identifiable. The superficial pontine venous network are identified in 72.5% of cases in the axial plane and were organised in longitudinal and transverse collectors, whose MR aspects are presented here.

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Les veines du pont. Anatomie sectionnelle en IRM

Résumé Le pont, enveloppé des citernes subarachnoïdiennes, est parcouru à sa surface par de nombreux vaisseaux qui constituent autant de points de repère topographiques en IRM que de rapports chirurgicaux. Nous présentons une étude de l'anatomie veineuse en coupe telle que l'IRM la révèle après injection de Gadolinium. Cette étude prospective comporte 40 patients indemmes de lésion de la fosse crânienne postérieure. Le pont est longé par un des collecteurs majeurs du tronc cérébral : la v. pétreuse supérieure, identifiée dans 95 % des cas. Elle se jette par un crochet caractéristique dans le sinus pétreux supérieur. La v. pétreuse inférieure n'a jamais été reconnue. Les vv. pontiques forment un réseau maillé visible dans 72,5 % des cas en coupes axiales et comportant des axes transversaux et longitudinaux dont les critères d'identification sont présentés selon le plan de coupe.

     

分泌性中耳炎中耳积液和血清中sIL－2R水平的初步研究

应用酶联免疫吸附法（ＥＬＩＳＡ）对３０例正常人血清（对照组）和６０例分泌性中耳炎患者（ＳＯＭ组）中耳积液和血清中可溶性白细胞介素２受体（ｓＩＬ－２Ｒ）进行了检测。结果示ＳＯＭ组血清ｓＩＬ－２Ｒ水平明显高于对照组，ＭＥＦ中其含量明显高于血清；鼻咽癌组血清及ＭＥＦ中ｓＩＬ－２Ｒ水平明显高于─般ＳＯＭ组；粘液组高浆液组；慢性组高于急性组（均Ｐ＜０．０１）。提示：血清及ＭＥＦ中ｓＩＬ－２Ｒ水平的测定有助于对ＳＯＭ患者免疫状态的评估；ＭＥＦ中ｓＩＬ－２Ｒ可能主要由局部中耳粘膜产生；ＭＥＰ中高浓度的ｓＩＬ－２Ｒ存在可能是ＳＯＭ迁延不愈的─个原因。