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991.
目的探讨眼眶动静脉畸形(AVM)致眼上静脉(SOV)扩张的影像学及血管造影表现。设计回顾性病例系列。研究对象6例临床表现与硬脑膜海绵窦瘘(CCF)相似的眼眶AVM患者。方法总结分析所有患者的影像学检查结果,如CT、MRI和选择性脑血管造影。主要指标影像学征象及血流动力学。结果CT和MRI均可显示所有患者的SOV扩张。另外,尚存在眼球突出、AVM畸形血管团等征象。所有6例AVM均位于眼眶内,1例尚合并颅内AVM。所有患者的主要引流静脉均为SOV,动脉包括脑膜中动脉、上颌动脉和眼动脉。结论眼眶AVM可引起与CCF相似的临床和影像学征象,但AVM通常不引起海绵窦膨大,血管造影仍是确诊的必需手段,而无创技术是辅助血管造影进行明确诊断的重要手段。(眼科,2007,16:395-398) 相似文献
992.
Ian F. Gutteridge 《Clinical & experimental optometry》1987,70(5):138-144
Data on the prevalence of all ocular conditions seen in 1500 consecutive optometric patients were obtained during an investigation into the effectiveness of routine visual field screening. In many instances, these are the first prevalence figures for optometric patient populations. Some of the estimates of prevalence are compared with other optometric and general population surveys. Many disorders were observed, the most frequent being slight to moderate increases in retinal arterial reflex and attenuation, optic cup/disc ratio of 0.4, shallow anterior chambers and family history of glaucoma. The occurrence of some conditions was sporadic, resulting from the relatively small sample. However, this survey may serve as an audit of ocular disease detection for other practitioners. 相似文献
993.
994.
Eight premature babies affected by hyaline membrane disease and needing mechanical respiratory support were ventilated by means of a VDR 1 (Bird Space Technology) respirator at 10 Hz during a mean time of 51 h. Before HFV 7 infants had been on conventional mechanical ventilation (CMV) and one on nasal CPAP. The values of mean airway pressure (MAP) and oxygenation index (PaO2/FIO2) on CMV and HFV were (mean and range): 1. CMV: MAP 15 (4–29) mm Hg, ox. index 15.47 (5.07–23.19) kPa; 2. HFV after 1 h: MAP 15 (10–19) mm Hg, ox. index 24.13 (9.07–46.12) kPa. Improved oxygenation allowed rapid reduction of FIO2 in the following hours. Only 3 infants were weaned directly from VDR 1, 5 were switched back to CMV mainly because of technical failures of the respirator. The change from HFV to CMV was associated with a fall of PaO2/FIO2 from 35.99 (15.86–74.52) to 22.39 (7.33–31.46) kPa. The mean time of artificial ventilation (CMV+HFV) was 121 h (range 46–166). Except for 1 pneumothorax no medical complications were seen during HFV, and all patients survived. Despite impressive improvements in oxygenation it is cautioned against the use of the VDR 1 because of the high incidence of technical problems. 相似文献
995.
Characterization and autoradiographic distribution of hemicholinium-3 high-affinity choline uptake sites in mammalian brain 总被引:4,自引:0,他引:4
R Quirion 《Synapse (New York, N.Y.)》1987,1(4):293-303
[3H]hemicholinium-3 (HC-3) binding characteristics have been investigated using membrane binding assays and in vitro receptor autoradiography. In rat brain membrane preparations, [3H]HC-3 binds with high affinity to an apparent single class of sites. [3H]HC-3 binding is Na+-dependent. The ligand selectivity pattern strongly suggests that [3H]HC-3 selectivity labels the high affinity choline uptake (HACU) in brain membranes (HC-3 greater than choline greater than carbamylcholine greater than acetylcholine). This hypothesis is also supported by quantitative autoradiographic data which demonstrate that the discrete distribution of [3H]HC-3 binding sites correlates very well with the known distribution of other cholinergic markers such as choline acetyltransferase (ChAT), acetylcholinesterase (AChE), HACU, and [3H]AH-5183 (blocker of the vesicular transport of acetylcholine). For example, high densities of labelling are observed for these different markers in the interpeduncular nucleus, anteroventral nucleus of the thalamus, striatum, basolateral nucleus of the amygdala, and an exquisite laminar distribution in the hippocampus. Similar autoradiographic distributions of [3H]HC-3 binding sites are observed in other mammalian species such as guinea pig and monkey. Finally, 7-day unilateral kainic acid lesions of the nucleus basalis magnocellularis (nbm) decrease cortical [3H]HC-3 binding and ChAT activity, although not to a similar extent. In summary, these results demonstrate that [3H]HC-3 is a selective ligand of the HACU in mammalian brain. Thus, it is now possible to characterize precisely various structural components of the cholinergic synapses using markers such as [3H]HC-3, ChAT, HACU, [3H]AH-5183, and selective muscarinic and nicotinic receptor radioligands. 相似文献
996.
支气管哮喘是由Th2介导的Ⅰ型变态反应,与内源性IL-12生成不足有关,该文综述了IL-12的生物学效应、IL-12表达障碍与支气管哮喘的关系以及IL-12、重组IL-12(rIL-12)在支气管哮喘治疗方面的应用前景。IL-12与Ⅰ型变态反应关系密切,内源性IL-12表达不足使支气管哮喘患者免疫系统向Th2方向偏移,在过敏原或病毒等外因的刺激下发生支气管哮喘。用IL-12对支气管哮喘进行免疫治疗已在动物实验中取得了显著效果,将IL-12、rIL-12或IL-12的内源性诱生物应用于人体的方法也在不断探索中并取得了一定效果,基于IL-12的治疗方法可能为支气管哮喘等变应性疾病的免疫治疗开辟新的途径。 相似文献
997.
目的:了解性病患者对安全性行为知识的知晓情况。方法:采用问卷方式对256例性病门诊患者进行安全套问题调查,并对所得数据进行统计分析。结果:从不使用安全套患者由初诊117例(45.7%)降到复诊时86例(33.6%);得知自己患性病后不用安全套与他人性交初诊118例(46.1%)下降到复诊时97例(37%);不用安全套与无性病症状的人性交会否感染性病回答不知道的由初诊58例(22.7%)下降到复诊时14例(5.5%)。结论:加大提倡使用安全套的宣传力度,提高人们对安全性行为的认识水平,提高安全套的使用率,是控制和预防性病及爱滋病经性接触传播流行的关键。 相似文献
998.
Inflammation and the Aging Process: Devil or Angel 总被引:1,自引:0,他引:1
Inflammation is often viewed as a pathologic mechanism leading to tissue damage and interference with function, such as the process of chronic tissue scarring or fibrosis. However, it is important to note that inflammation is a crucial component of normal tissue repair as well as being fundamental to the body's defense against infection. Considering inflammation as a "causative agent in aging" belies the underlying mechanisms whereby the acute inflammatory response is necessary for survival, and efforts to reduce and control the inflammatory response leave the host susceptible to infectious agents and improper healing. Chronic inflammation inevitably has initiating mechanisms that include immune, autoimmune, and metabolic pathways, leading to the activation and presence of the host-protective response. It is more appropriate to target the underlying initiating conditions than the inflammatory process that ensues and treat the basic mechanisms of disease rather than interfere in a very important protective mechanism of the host. 相似文献
999.
目的 观察辛伐他汀(Sim)对白细胞在早期糖尿病大鼠视网膜毛细血管中黏附、堆积的影响,探索他汀类药物可能的非调脂性治疗作用.方法 Wistar大鼠40只,随机分为正常对照组、糖尿病组(DM)、糖尿病Sim组(DMsim)和糖尿病生理盐水组(DM saline).腹腔注射链脲佐菌素(STZ)建立糖尿病模型,成模后Sim组予以Sim15 mg/(kg·d);DMsim组等量灌胃,2周后处死动物,取右眼制备视网膜石蜡切片,行形态学观察及CD45-MAb免疫组织化学研究.结果 CD45在正常大鼠视网膜血管内皮细胞胞膜中有表达,DM组CD45的表达明显增加,与正常对照组、DMsim组比较差异有统计学意义(P<O.05).结论 早期糖尿病大鼠视网膜白细胞黏附性增加,Sim可显著地抑制白细胞在视网膜中的黏附和堆积,改善糖尿病大鼠视网膜微循环. 相似文献
1000.
J.S. WIGGLESWORTH 《Histopathology》1987,11(7):671-689
The major forms of lung pathology in the perinatal period are reviewed with emphasis on disturbances of growth and maturation. Lung hypoplasia results from impairment in the physiological control of lung growth during the fetal period. It is more common than organogenetic defects which are discussed only briefly. Hyaline membrane disease is now seldom seen in a pure form due to improvements in perinatal care. However, its complications and sequelae such as interstitial emphysema, pneumothorax and bronchopulmonary dysplasia are encountered more frequently. In addition, a wide variety of pathological processes may localize to, or be expressed in, the lung of the newborn, notably asphyxial changes, persistent pulmonary hypertension, haemorrhage and infection. 相似文献