辐射对豚鼠鼻黏膜组织结构及微血管的影响

目的：探讨辐射对豚鼠鼻黏膜结构及微血管的损伤。方法：选择健康豚鼠84只，随机分为对照组（12只）及照射组（72只）。均在同样条件下喂养。将照射组豚鼠置于直线加速器射线内照射，每周1次，每次照射5Gy，计3周，总剂量15Gy，建立辐射损伤动物模型。分别于照射后0．5、1.0、2．0、3．0、5．0、6．0个月处死动物12只，随机取6只做鼻腔黏膜微血管铸型，另6只做病理检查。对照组在假照射后6个月处死动物，随机各选6只分别做鼻黏膜微血管铸型检查和病理检查。结果：照射组豚鼠的鼻黏膜辐射后早期表现为急性炎症反应，黏膜大量坏死、脱落，电镜下见仅少部分黏膜表面还被覆着正常的纤毛结构。以后黏膜开始修复，至6个月时基本结束，但大部分黏膜失去了正常的纤毛柱状上皮结构特点，部分区域甚至代为组织转化的鳞状上皮；微血管铸型可见，早期改变为毛细血管扩张充血及血管内皮细胞肿胀，以后逐渐出现毛细血管的扭曲变形、闭塞及中断，毛细血管数量大量减少，致血液回流障碍，微静脉萎瘪。后期部分区域出现新生的毛细血管，但结构紊乱，不具备微循环的功能。结论：鼻黏膜的损伤、晚期的鳞状上皮组织转化以及鼻黏膜微循环的破坏是放疗后鼻腔功能障碍的病理学基础。     

An explanation of the noncorrespondence between assessment methods of cyclosporin

Various methods of determining cyclosporin (CyA) levels in patients after kidney transplantation were compared. These included polyclonal antibody (pcAb-), specific and nonspecific monoclonal antibody (S- and NmcAb-) radioimmunoassays (RIA), and high performance liquid chromatography (HPLC). The results obtained by the various methods when compared showed some correlation but did not correspond. A probable explanation for part of this noncorrespondence is the presence of monoclonally crossreactive metabolites (CyA-M). Another reason was that the concentration of CyA in the standards supplied with the RIA kits was found to be higher than stated.     

海口市550名医学生膳食营养状况

目的了解海口市医学生膳食营养状况,为改善学生膳食质量提供指导意见。方法采用24h膳食回顾法,记录550名医学生连续5d的膳食情况,利用营养计算器V6.0版及Excel软件对结果进行分析。结果大多数学生能量、维生素A、维生素C、钙等营养素摄入量不足,男生膳食维生素A、维生素C、钙的摄入量分别为推荐摄入量的63.63%,50.00%及44.63%,女生分别为61.00%,50.00%和44.13%,女生能量摄入量为推荐摄入量的81.60%。膳食钙磷比男、女生分别为0.31和0.40。早、中、晚三餐能量分配分别为18%,43%和39%。结论海口市医学生膳食结构不够合理,应增加能量、维生素A、维生素C、钙的摄入量。     

Using online databases to find peer-reviewed journal articles on injury prevention and safety promotion research: a study of textword queries by SafetyLit users.

OBJECTIVE: To assess the capacity of textword queries to provide a comprehensive listing of articles on injury prevention and safety promotion (IPSP) concepts in a literature database. METHODS: All terms used to search SafetyLit (a database of scholarly literature selected for its relevance to the IPSP field) during the years 2000-2005 were listed and then examined to identify terms that are synonyms for the same concept. Terms were grouped by concept, the number of queries that used terms within each concept category were summed, and the concepts were then ordered by the total number of searches for each concept category. For each textword, the proportion of all articles for that concept that could be found by using it alone was calculated. RESULTS: Each of the 25 most searched-for concepts has 4 to 40 synonyms. Sixteen of the concepts required queries using two or more terms to find 75% of the available articles. Few searchers used a sufficient number of textword synonyms in their queries to return a complete listing of the available material. CONCLUSION: On the basis of this study, queries using only one or two textword terms are insufficiently sensitive to find all relevant journal articles about an IPSP concept.     

Transmission electron microscopy of early microbial colonization of human enamel and root surfaces in vivo

Abstract – This study describes the early microbial colomization of teeth by the use of light-and transmission electron microscopy. Six dental students carried a total of 60 test pieces of unerupted enamel and root surface in intraoral acrylic appliances for 4, 8, 12, 24 and 48 h, during which periods oral hygiene was abandoned. Pronounced variations were recorded in structure and thickness of the pellicle across the individual surfaces of both dental tissues. Bacterial single-cell colonization increased the electron density of the adjoining pellicle. Micro-colonies of bacteria were observed in relation to enamel surface irregularities such as perikymata, while the distribution on root surfaces appeared incidental. Root surfaces were generally colonized by thicker deposits than homologous enamel surfaces although the structural composition of the microbiota was similar. Gram-positive bacteria with thick cell walls appeared in coccoid or rod-shaped configurations depending on the age of the bacterial deposit. These bacteria were further characterized by selective invasion between collagen fibers. After 48 h the complexity of the microbiota was increased by the establishment of new bacterial species in the superficial layer. It is concluded that the pattern and composition of the early microbiota on teeth is more complex and variable than hitherto assumed.     

两种方法解决介入治疗术后排尿困难效果的比较

冠状动脉造影术,使冠心病的诊断、治疗水平明显提高。但床上排尿困难是术后常见的护理问题,采用常规的方法,效果不佳,常需导尿术解决,既增加了患者的痛苦,又增加了护理工作量。我科2003年3月~2006年10月采取开塞露肛注刺激直肠诱发排便-排尿反射,较好地解决了床上排尿困难的问题。并与常规诱导排尿的方法进行了比较,现报告如下。临床资料对象选择冠状动脉造影术后排尿困难者60例,其中男性42例,女性18例,年龄20~78岁,平均53岁,随机分为对照组和观察组各30例,两组年龄、性别差异无显著性,具有可比性。方法(1)观察组:给予开塞露肛注排便以诱导…     

Quantitative MRI of the brain in children with sickle cell disease reveals abnormalities unseen by conventional MRI

Conventional MRI (cMRI) has shown that brain abnormalities without clinical stroke can manifest in patients with sickle cell disease (SCD). We used quantitative MRI (qMRI) and psychometric testing to determine whether brain abnormalities can also be present in patients with SCD who appear normal on cMRI. Patients 4 years of age and older with no clinical evidence of stroke were stratified by cMRI as normal (n = 17) or abnormal (n = 13). Spin-lattice relaxation time (T1) of gray and white matter structures was measured by the precise and accurate inversion recovery (PAIR) qMRI method. Patient cognitive ability was assessed with a standard psychometric instrument (WISC-III or WISC-R). In all 30 patients with SCD, qMRI T1 was lower than in 24 age- and race-matched controls, in cortical gray matter (P < .0006) and caudate (P < .0009), as well as in the ratio of gray-to-white matter T1 (P < .008). In the 17 patients who were shown to be normal by cMRI, qMRI T1 was still lower than in controls, in both cortical gray matter (P < .02) and caudate (P < .004). Histograms of voxel T1 show that the proportion of voxels with T1 values intermediate between gray and white matter (ie, consistent with encephalomalacia) was 9% higher than controls in patients shown to be normal by cMRI (P < .05) and 15% higher than controls in patients shown to be abnormal by cMRI (P < .0005). The full scale intelligence quotient (FSIQ) of all patients with SCD was 75, compared to the FSIQ of 88 in a historical control group of patient siblings (P < .001). The FSIQ of patients shown to be normal by cMRI was 79, significantly lower than the FSIQ of patient siblings (P < .04). The FSIQ of 71 in patients shown to be abnormal by cMRI was significantly lower than both the patient siblings (P < .005) and the patients shown to be normal by cMRI (P < .04). Patients shown to be abnormal by cMRI scored lower than patients shown to be normal by cMRI, specifically on the subtests of vocabulary (P = .003) and information (P = .03). Cognitive impairment is thus significant, even in patients with SCD who were shown to be normal by cMRI, suggesting that cMRI may be insensitive to subtle neurologic damage that can be detected by qMRI. Because cognitive impairment can occur in children normal by cMRI, our findings imply that prophylactic therapy may be needed earlier in the course of SCD to mitigate neurologic damage.     

Idiopathic normal pressure hydrocephalus associated with empty sella

A 70-year-old female presented with the clinical triad of normal pressure hydrocephalus (NPH) and senile tremor. Neuroimaging disclosed findings of both NPH and empty sella (ES). A ventriculoperitoneal shunt did not modify the clinical course except for a mild and transient improvement, and shunt malfunction occured later on. The association of NPH and ES may result from a common underlying mechanism such as transient increases in intracranial pressure.