医学毕业生心理调查分析及对策

目的调查分析医学毕业生心理,采取教育对策。方法应用Zung焦虑抑郁自评量表(SAS、SDS)对医学院校187名应届医学毕业生进行抽样调查。结果本组SAS、SDS标准分平均值为37.04±9.08与40.18±10.57;SAS男性37.07±9.38,与女性略同;SDS男性40.55±10.95高于女性39.90±10.30,差异不显著。SAS、SDS≥50的高分人数57例,占30.46%,其中≥50轻度焦虑抑郁为19.24%,≥60重度焦虑11.22%;男、女性别组焦虑抑郁者分别为25例与33例,各占28.09%与33.67%,女性轻度抑郁比例多于男性,差异显著。结论本组医学生情绪状态整体水平尚可,少数学生偏离正常。女性焦虑抑郁人数分布高于男性。应加强素质教育,开展心理咨询,完善就业工作体制,拓宽就业渠道。     

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     

实验性抑郁症大鼠缰核和海马BDNF基因表达

目的：研究抑郁症大鼠缰核和海马BDNF基因的表达情况。方法：采用长期未预知应激刺激致大鼠抑郁症模型，运用open-field和forced swinmming test法观察大鼠行为学变化。运用免疫组化法检测缰核和海马BDNT基因的表达。结果：与正常对照组相比，抑郁症模型组大鼠海马和缰核均表现为BDNF阳性细胞数量明显减少。结论：实验性抑郁症大鼠缰核、海马BDNF基因表达水平降低。     

一种可生物降解温度敏感型聚乙二醇-聚己内酯-聚乙二醇水凝胶的合成和表征

合成了一系列分子量较低的聚乙二醇．聚己内酯-聚乙二醇（Poly（ethylene glycol）-Polycaprolactone-Poly（ethylene glycol），PEG-PCL—PEG）三嵌段共聚物。分别采用FTIR和1H—NMR对其结构进行了表征。所合成的PEG-PCL-PEG共聚物具有良好的水溶性，当水溶液浓度高于临界凝胶浓度（Critical gel concentration，CGC）时，随着温度的变化聚合物水溶液会呈现特有的凝胶-溶胶转变。研究了共聚物亲水疏水链段的比例和长度，以及热历史等对凝胶-溶胶转变行为的影响。通过调节上述条件，可以在一定程度上拓宽凝胶-溶胶转变温度范围，有助于PEG—PCL-PEG水凝胶在可注射药物控制释放系统等方面的应用。     

红外多波长无创人体血糖检测阵列模型的研究

无创血糖监测不仅可以减少患者的痛苦，还能进行连续测量，从而降低并发症的发生，它是一种不需收集血样进行体内血糖浓度测量的新技术。本文根据朗伯-比尔定律(The Lambert—Beer Law)原理，为克服无创血糖检测研究中的难点和缺陷，详细分析了血糖红外光谱的吸收特性，利用阵列技术设计了红外多波长无创血糖检测传感器阵列模型，对关键技术进行了讨论。用ME算法建立了信号检测和标定数学模型，结合了人体各种影响因素，使红外无创血糖检测的精度和稳定性得到了改善。列举了详细的实验实施步骤，同时叙述了系统调试的详细过程，讨论了无创血糖检测中需要注意的问题。     

Retinal dehydrogenase-2 is inhibited by compounds that induce congenital diaphragmatic hernias in rodents

Currently, the etiology of the serious developmental anomaly congenital diaphragmatic hernia (CDH) is unknown. We have used an animal model of CDH to address this issue. We characterized four separate teratogens that produced diaphragmatic defects in embryonic rats that are similar to those in infants with CDH. We then tested the hypothesis that all these agents share the common mechanism of perturbing the retinoid-signaling pathway. Specifically, inhibition of retinal dehydrogenase-2 (RALDH2), a key enzyme necessary for the production of retinoic acid and that is expressed in the developing diaphragm, was assayed by measuring retinoic acid production in cytosolic extracts from an oligodendrocyte cell line. The following compounds all induce posterolateral defects in the rat diaphragm; nitrofen, 4-biphenyl carboxylic acid, bisdiamine, and SB-210661. Importantly, we demonstrate that they all share the common mechanism of inhibiting RALDH2. These data provide an important component of mounting evidence suggesting that the retinoid system warrants consideration in future studies of the etiology of CDH.     

表达鼠精子Cyritestin蛋白的减毒沙门氏菌疫苗株的构建及其鉴定

目的 构建表达鼠精子eyritestin蛋白的可口服减毒沙让氏菌活疫苗株。方法 应用质粒TAZ83／13，将之进行双酶切获得含有成熟cyritestin蛋白cDNA序列的酶切片段。将其插入表达载体yA3149中，构建重组质粒pCFL。将该重组质粒转入鼠沙门氏伤寒杆菌疫苗株X4632和X4550中，以获得重组菌株X4632（pCFL)和X4550（pCFL)。结果 该两种无抗药性的重组菌株在体外营养选择压力下，可较稳定地携带重组质粒传代繁殖。X4550(pCFL)在体内可较稳定地害居于Peyer‘s结，肠系膜淋巴结和脾脏；X4632（pCFL)可较稳定地定居于Peyer‘s结。二者均可表达被抗cyritestin单抗（mAb)识别的重组cyritestin蛋白。口服该疫苗菌株无明显的毒性作用。结论 X4632（pCFL),X4550（pCFL)疫苗株的构建，为研究以cyritestin为靶抗原的精子抗原避孕疫苗打下了基础。     

Connexin26 gene ( GJB2): prevalence of mutations in the Chinese population

The connexin26 gene ( GJB2) has been shown to be responsible for DFNB1 and DFNA3 (Autosomal Recessive Hereditary Nonsyndromic Deafness Locus 1 and Autosomal Dominant Hereditary Nonsyndromic Deafness Locus 3). Two hundred ten independently ascertained Chinese probands with nonsyndromic hearing loss (NSHL) were evaluated for mutations in GJB2, including 43 probands from families with more than one sib with NSHL, likely indicating dominant inheritance, and sporadic cases of NSHL, compatible with recessive inheritance. Of the 210 probands, 43 (20%) were homozygous or heterozygous for mutations in GJB2. Four different mutations were identified: 35delG, 109G-A, 235delC, and 299-300delAT. It was confirmed that GJB2 mutations are an important cause of hearing loss in this population. Of these four mutations, 235delC was the most prevalent at 93%; yet the 35delG mutation, which is the most common GJB2 mutation in Caucasian subjects (Europeans and Americans), was found in low frequency in the present study. It appears from our limited data and reports from other East Asians that 235delC is the most prevalent GJB2 mutation in these populations. GJB2 mutations are consistent with ethnic predilections.     

戊二醛交联甲壳胺膜的制备及其渗透性的研究

本文制备戊二醛交联甲壳胺膜。研究了戊二醛交联对膜的亲水性，结晶性的影响；探讨了交联对肌肝、尿素、尿酸的渗透；测定膜在于干态和湿态下的力学机械性能。     

Reaction of chitosan with genipin and its fluorogenic attributes for potential microcapsule membrane characterization

This study investigates the fluorogenic characteristics of the chitosan-genipin reaction for applications in microencapsulation research. Results showed that the chitosan-genipin reaction generated a colored and fluorescent product, with optimal excitation and emission wavelengths at 369 and 470 nm, respectively. Furthermore, it was found that reaction conditions affected the fluorescence intensity of the product. Mixture at the ratio of 4:1 (chitosan: genipin by weight) fluoresced the most. It also fluoresced stronger if the reaction occurred at higher temperature, with the intensity of 10.4 x 10(5) CPS at 37 degrees C, 5.9 x 10(5) CPS at 20 degrees C, and 2.5 x 10(5) CPS at 4 degrees C. As well, the fluorescence of the mixture developed gradually over time, attaining the emission maxima of 2.9 x 10(5), 7.6 x 10(5), and 10.0 x 10(5) CPS in 1, 6, and 18 h, respectively. Chitosan-coated alginate microcapsules were prepared without prior labeling, to which subsequent genipin treatment was applied in order to examine the potential of using genipin in microcapsule characterization. Chitosan bound to the alginate beads interacted with genipin, from which the resultant fluorescent signals allowed for clear visualization of the chitosan coating under confocal laser scanning microscopy. The relative fluorescence intensity across the chitosan membrane was found to be considerably higher than the controls (175 vs. 50). The membrane thickness measured was 29.2 +/- 7.3 microm. These findings demonstrate a convenient and effective way of characterizing chitosan-based microcapsules using genipin as a fluorogenic marker, a technique that will be useful in microcapsule research and other biomedical applications.