医学生"网络成瘾症"产生的原因和对策

文章针对目前医学生“网络成瘾症”的现状进行了分析,并指出了产生的原因和解决问题的办法,以求达到标本兼治。最后提出三点预防医学生“网络成瘾症”的对策：一是高校及其附属医院要为医学生营造宽松愉快的学习、生活环境;二是呼吁家长关注医学生身心发展的特殊规律,建立良好的家庭环境;三是建立和完善与网络社会相应的法律法规,规范医学生的网上行为。     

Therapeutic effect of antioxidant on impaired neutrophil function after burns

The present study was carried out with the aim of elucidating the effect of administration of antioxidants vitamin E, Rubiside, and Rubiquinone on neutrophil function in burns. The experimental results showed that the survival rates of the animals were higher in antioxidant Rubiside and Rubiquinone treatment groups, as compared with control group 7 days post-burn. In the control group, Superoxide dismutase (SOD) activity of blood was markedly decreased, malondialdehyde (MDA) levels in serum were sharply increased, neutrophil chemiluminescence (PMN-CL), neutrophil (PMN) phagocytic rate and phagocytic index were markedly decreased (P less than 0.05) after fluid resuscitation for the observation period of 7 days, as compared with that before resuscitation. It was also found that significant negative correlation existed between MDA levels of serum and PMN phagocytic rate (P less than 0.01) in the control group. On the contrary, after the administration of antioxidant agent vitamin E, Rubiside or Rubiquinone in three different groups, SOD activity was markedly higher, MDA levels were markedly lower, and PMN-CL, PMN phagocytic rate were higher as compared with that of the control group. The experiment suggests that antioxidants could be used as an adjunct in the resuscitation of burn shock, especially in cases when resuscitation is delayed because of various reasons.     

Metaproterenol (Alupent) metered dose inhaler in children 5-12 years of age

This multiclinic study was performed to evaluate the safety and efficacy of metaproterenol sulfate (Alupent) metered dose inhaler in children with asthma ages 5 to 12 years. A total of 268 children completed this study according to the protocol, having received either metaproterenol or placebo for 30 consecutive days. Full spirometric testing was done pre- and postdose on Days 1 and 30 for a total duration of 6 hours on each day. The results showed that metaproterenol was consistently superior to placebo in all pulmonary function parameters measured on Days 1 and 30. This difference was statistically significant for peak values and areas under the curves for both FEV1 and FEF25-75%. There were no significant side effects noted. We conclude that metaproterenol metered dose inhaler is safe and effective in the treatment of asthma in children ages 5 to 12 years.     

Three years' experience with levonorgestrel-releasing intrauterine device and Norplant-2 implants: a randomized comparative study

A randomized comparative study of levonorgestrel-releasing intrauterine device (LNG-IUD) and Norplant^R-2 implants was carried out in 200 women for 36 months. Three thousand one hundred woman-months of use were observed with each device. Only one pregnancy occurred in users of LNG-IUD at the 12th month of use. The change in bleeding pattern was the most frequent reason for discontinuation. The discontinuation rate for irregular bleeding with Norplant-2 was 17.3 and 26.8 at 24 and 36 months, respectively, as compared to 3.3 with LNG-IUD at both 24 and 36 months. The differences were statistically significant. Removal for amenorrhea and pain only occurred in acceptors of LNG-IUD. About 20–40% of women using Norplant-2 had prolonged bleeding through 36 months. The percentage of amenorrhea in LNG-IUD was the highest (29.3%) at the end of two years of use. More than 97% of subjects reported satisfaction with the methods used by themselves.

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Resumen Un estudio aleatorizado en el que se comparan los dispositivos intrauterinos que descargan levonorgestrel (LNG-IUD) con los implantes Norplant-2 se realizó en 200 mujeres durante 36 meses. Se observó un período de utilización correspondiente a tres mil cien meses-mujer con cada uno de los dispositivos. Hubo un solo embarazo, en el decimosegundo mes, entre las usuarias de LNG-IUD. La alteración del flujo menstrual fue la razón invocada con mayor frecuencia para el abandono del método. Los porcentajes de abandono por la irregularidad de la menstruación en el caso de los Norplant-2 fue de 17,3 y 26,8 a los 24 y 36 meses, respectivamente, en comparación con 3,3 con los LNG-IUD a los 24 y 36 meses. Estas diferencias son estadísticamente significativas. El retiro por amenorrea y dolores sólo ocurrió entre las mujeres que tenían los LNG-IUD. Los Norplant-2 ocasionaron sangrado prolongado durante los 36 meses estudiados en alrededor del 20 al 40% de las mujeres. El porcentaje de amenorrea con los LNG-IUD llegó al nivel máximo (29,3%) al cabo de dos años de uso. Más del 97% de las mujeres se mostraron satisfechas con los métodos que utilizaban.

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Resumé Une étude randomisée comparant les dispositifs intra-utûrins libérant du lévonorgestrel (LNG-IUD) aux implants Norplant-2 a été effectuée sur 200 femmes pendant 36 mois. On a ainsi observé une période d'utilisation correspondant à trois mille cent mois/femme avec chacun des dispositifs. Une seule grossesse s'est produite, au douzième mois, parmi les utilisatrices de LNG-IUD. L'altération du flux menstruel a été la raison le plus souvent invoquée pour l'abandon de la méthode. Les pourcentages d'abandon du fait de l'irrégularité de la menstruation dans le cas des implants se sont élevés à 17,3 et 26,8 après respectivement 24 et 36 mois, alors qu'ils n'atteignaient que 3,3 pour les LNG-IUD, tant à 24 qu'à 36 mois. Ces différences sont statistiquement significatives. Le retrait à la suite d'aménorrhée et de douleurs n'a été constaté que chez des femmes portant les LNG-IUD. Le Norplant-2 a occasionné des saignements prolongés pendant les 36 mois étudiés chez environ 20 à 40% des femmes. Dans le cas des LNG-IUD, le taux d'aménorrhée était le plus élevé (29,3%) au terme de deux années d'utilisation. Plus de 97% des patientes se sont dites satisfaites de la méthode qu'elles appliquaient.

     

Computerized tomography based on DEI refraction information.

Conventional computerized tomography (CT) technique is based on the absorption contrast. In recent years, X-ray phase-contrast CT (PCCT) has been developing rapidly. It uses the phase information to reconstruct the object and provide high contrast and spatial resolution. Diffraction enhanced imaging (DEI) method is one of the three phase-sensitive X-ray imaging techniques. DEI method employs an analyzer crystal to extract the object's refraction information which can be used for CT. However, when DEI refraction CT is combined with the conventional CT algorithm, it should be satisfied that the refraction information of an arbitrary point in the object is invariable at every projection view. In this paper, the invariance condition of refraction information is analyzed and two feasible methods are provided for reconstruction. Using these two methods, two samples of weak absorption are reconstructed with the experimental data obtained at Beijing Synchrotron Radiation Facility (BSRF).     

温针灸治疗颞下颌关节功能紊乱病36例

目的:比较温针灸与口服西药治疗颞下颌关节功能紊乱病的疗效。方法:治疗组36例取下关、牵正、颊车、阿是穴、合谷(双)行温针灸,对照组口服地西泮、吲哚美辛。结果:治疗组治愈率80·6%、总有效率100%,对照组治愈率40·6%、总有效率78·1%,两组有非常显著性差异(P<0.01)。结论:温针灸治疗颞下颌关节功能紊乱病方法简单,疗效显著。     

Sympathoadrenal excitation and inhibition by lower brainstem stimulation in cats

Effects of stimulation of brainstem sites on hemodynamics and plasma catecholamine levels were assessed in cats under chloralose-urethane anesthesia. Pressor areas of the dorsal medulla (DM) and ventrolateral medulla (VLM) and the depressor area of the paramedian reticular nucleus (PRN) were stimulated electrically using a monopolar electrode, or chemically using sodium glutamate microinjection. Plasma levels of norepinephrine (NE) and epinephrine (EPI) were measured in caval blood above the adrenal veins. Electrical stimulation of the DM and VLM produced increases in blood pressure and in plasma NE and EPI levels that were enhanced after acute vagotomies. The NE and EPI responses were attenuated after acute, bilateral adrenalectomies, confirming augmented adrenomedullary secretion, whereas the pressor responses were intact. Injection of sodium glutamate into the same pressor regions of the DM or VLM also produced pressor responses and elevated plasma catecholamine levels, indicating that the responses resulted from activation of neuronal perikarya. Stimulation of the PRN attenuated pressor and catecholamine responses during stimulation of the DM and VLM. The results indicate that pressor responses during stimulation of the DM and VLM are due at least partly to activation of perikarya in these regions, are associated with but not dependent on adrenomedullary activation, and are enhanced after vagotomy; and that neurons of the PRN exert inhibitory modulation of the pressor and adrenomedullary responses during stimulation of VLM and DM.     

Coexistence of autonomic and somatic mechanisms in the pressor areas of medulla in cats.

The effects of electrical stimulation and microinjection of sodium glutamate (0.5 M) in the sympathetic pressor areas of the dorsal medulla (DM), ventrolateral medulla (VLM), and parvocellular nucleus (PVC) on the knee jerk, crossed extension, and evoked potential of the L5 ventral root produced by intermittent electrical stimulation were studied in 98 adult cats anesthetized with chloralose and urethane. During electrical and glutamate stimulation of these pressor areas, in addition to the rise of systemic arterial blood pressure marked inhibition of the spinal reflex was produced, indicating presence of neuronal perikarya responsible for these actions. Mild to moderate augmentation of spinal reflexes was also observed during brain stimulation but only in a few cases. The magnitude of the somatic effects among the pressor areas of the VLM, DM, and PVC subsequent to glutamate activation was about the same. Induced spinal reflex inhibition, independent from the baroreceptor and vagal influence, remained essentially unaltered after acute midcollicular decerebration. The inhibition was also observed in cats decerebellated 8-10 days in advance. The inhibition was not affected after bilateral electrolytic- or kainic-acid-induced lesions in the paramedian reticular nucleus (PRN). On the contrary, PRN-induced spinal reflex inhibition was attenuated after bilateral lesions in the DM or VLM. Data suggest that there coexists neuronal subpopulations in the VLM, DM, and PVC that can affect both the sympathetic pressor systems and spinal reflexes.