改良小梁切除术治疗伴有高眼压及大瞳孔的急性房角关闭

目的 评价改良小梁切除术治疗伴有高眼压及大瞳孔的急性房角关闭的临床疗效。方法收集2005年1月至2009年3月中山大学中山眼科中心青光眼专业实施改良小梁切除术治疗伴有高眼压及大瞳孔的急性房角关闭21例（21眼）的临床资料,对术后并发症及手术前后的眼压、视力、瞳孔等进行统计分析。 结果 术前眼压(48.25±3.14) mmHg,平均用降眼压药种类3.35种,明显高于出院时眼压(10.47±1.15)mmHg(t=11.4573,P＜0.01)及术后3个月眼压(13.86±0.93) mmHg(t=11.2641,P＜0.01)。出院视力(0.09±0.05)与术前视力(0.11±0.06)差异无统计学意义(沁0.8702,P= 0.3913),术后3个月视力(0.21±0.04)则稍好于术前（t=-2.7907,P=0.0112）。术前瞳孔垂直径(5.81±0.23) mm与出院时瞳孔垂直径(5.92±0.21 )mm差异无统计学意义（t=-1.5013,P=0.1672）。无严重并发症发生。 结论 改良小梁切除术是治疗伴有高眼压及大瞳孔的急性房角关闭的有效方法,术中分次放房水、巩膜瓣调节缝线、术毕形成前房等措施可有效减少严重并发症的发生。     

Inhalational anesthetics inhibit spreading depression: relevance to migraine

Cortical spreading depression (SD) has not been shown in the human neocortex by direct cortical recordings. However, animal studies suggest that cortical injury, such as that occurring during neurosurgical procedures, should result in the initiation of SD. It is possible that inhibition of SD by volatile anesthetic agents may partially explain the failure to observe SD in the human neocortex during surgery. This study examines the effect of the anesthetic agents α-chloralose, halothane, nitrous oxide and isoflurane on the initiation of cortical SD in the cat neocortex. SD was seen in 100% of cats anesthetized with α-chloralose ( n = 15), in 3 of 7 (42%) animals anesthetized with isoflurane ( p < 0.05, χ² with Yates correction) and none of the animals ( n = 4, 6 hemispheric preparations) anesthetized with halothane ( p < 0.005, χ² with Yates correction, halothane vs α-chloralose group). In all cases this inhibitory effect was reversible. In four animals the administration of nitrous oxide (66%) reduced the inspired concentration of isoflurane required to inhibit SD by 0.75%. This study suggests that halothane, and to a lesser extent isoflurane and nitrous oxide, protect against the initiation of cortical SD. This observation may partially explain why SD has not been demonstrated in human neocortex during surgery. Further studies are needed to determine if SD may occur under pathological conditions, such as during migraine with aura, where the cortex may be predisposed to SD.     

Is fecundability associated with month of birth? An analysis of 19th and early 20th century family reconstitution data from The Netherlands

The relationship between fecundability and month of birth was investigated in a cohort of 1526 women who married between 1802 and 1929, using only women whose first marriage occurred before the age of 35 years. On the basis of their time to pregnancy (TTP, calculated as time between wedding and first birth minus gestational length), women were categorized into two groups: fecunds (TTP up to 12 months or prenuptial conceptions, n = 1348) and subfecunds (TTP >18 months, n = 118). By use of logistic regression, cosinor functions with a period of 1 year or 6 months and variable shift and amplitude were fitted through the monthly odds of subfecunds versus fecunds. The best fitting curve was unimodal, with a zenith in September (P = 0.13 for H0: no differences). Exclusion of childless women (n = 36, minimum follow-up 5 years) from the subfecunds led to a similar curve (P < 0.01), while childless women, as compared with fecunds, showed a birth distribution that was best represented with a bimodal curve with zeniths in January and July (P = 0.06). This study provides evidence for the existence of differences in fecundability by month of birth. The cause of this relationship is unclear, but may lie in a melatonin-dependent circannual variability of the quality of the oocyte.      

藏羚羊和藏系绵羊左心室收缩功能的比较研究

目的:探讨藏羚羊适应高原低氧环境的左心功能特点。方法:捕捉海拔4 300 m藏羚羊9只、藏系绵羊10只运至格尔木(海拔2 800 m)实验基地。测定二者的心脏/体重比(HW/BW)、右心室/(左心室+室间隔)重量比[RV/(LV+IVS)];应用心导管技术测定心率(HR)、收缩压(SBP)、舒张压(DBP)、左室等容收缩期心室内压力上升最大速率和左室等容舒张期心室内压力下降最大速率(±dp/dt)。以格尔木市的氧浓度(21.1%)为基线,分别给予更低浓度氧14.6%、12.5%(分别相当于海拔5 300 m、6 300 m)的低氧吸入15 min后重复测定以上指标。应用透射电镜观察心肌超微结构。结果:藏羚羊HW/BW显著高于藏系绵羊(P0.01),基础状态下藏羚羊SBP低于藏系绵羊(P0.05),+dp/dt与藏系绵羊比无显著差异,吸入14.6%和12.5%的低氧气体后藏羚羊+dp/dt分别升高至145.1%和148.1%,而藏系绵羊分别降低至68.4%和70.5%(P0.05);电镜下观察藏羚羊心肌超微结构与藏系绵羊比较,其心肌细胞线粒体较为丰富。结论:藏羚羊心脏对高海拔低氧环境的适应,是通过增加心脏器官的重量及心肌细胞线粒体的含量来实现,其心肌收缩功能的适应性特征为:在静息状态下以较低的左心室心肌收缩力来降低氧耗量以此适应高原低氧环境,而以海拔更高的较低氧浓度为应激条件下,左心室心肌收缩力明显升高。提示:藏羚羊作为高原适应性动物,经过漫长的自然选择其心脏对高原低氧环境的适应不同于藏系绵羊。     

红景天抑制人脐静脉内皮细胞生长的初步研究

目的:利用体外培养人脐静脉内皮细胞,观察中药红景天对细胞生长的影响,初步探讨急、慢性高原病患者服用中药红景天防治高原病及改善症状等的作用机制。方法:培养人脐静脉内皮细胞EVC-304,设对照组与加药组,加药组分别加入不同浓度的红景天,培养3d后计数。加药组及对照组细胞用瑞氏染料染色并拍照。收集细胞以流式细胞术检测细胞周期。结果:对照组细胞形态正常,成梭形,排列紧密,分散均匀。加药组细胞数量明显减少,细胞皱缩,聚集成团,形态各异。流式细胞术检测显示加药组G1期细胞含量增多,S期细胞减少。结论:红景天具有抑制血管内皮细胞生长的作用,可能是通过抑制细胞的增殖来抑制内皮细胞生长。抑制血管内皮细胞生长对于阻止血管内膜增生,防止形成肺动脉高压,降低慢性高原病发病率具有实际应用意义。