肺音信号的自回归谱谱阵分析

本文应用自回归模型方法研究了各种肺音信号的ＡＲ谱谱阵，并与傅里叶功率谱谱阵作了对比，探讨了两种谱阵的特点与差异，实验结果表明：肺泡呼吸音ＡＲ模型阶次为６阶，气管音ＡＲ模型阶次为１４阶，哮鸣音与喘鸣音的ＡＲ模型阶次分别为１２阶与６阶，正常呼吸音（肺泡呼吸音与气管音）功率谱为连续谱，异常连续性肺音（哮鸣音与喘鸣音）功率谱为离散线状谱，音肺信号谱阵方法可显示出肺音的时变特性，有利于对肺音作动态分析。     

Mannose prevents lipopolysaccharide-induced acute lung injury in rats

Objective: To investigate the effect of mannose on lipopolysaccharide (LPS) induced acute lung injury (ALI) in rats. Methods: Ten groups of Sprague–Dawley rats were used: 1) the control group received an intratracheal instillation of saline, 2) the LPS group received an intratracheal instillation of LPS (3 mg/kg), 3–6) the mannose groups were injected i.v. with 15, 45, 135, and 405 mg/kg mannose, 7–9) the glucose, galactose, and fructose groups were injected with different hexoses (135 mg/kg), and 10) the dexamethasone (DXM) group was injected with DXM (2 mg/kg). In groups 2–8, LPS was administered after injection of drugs. Lung wet/dry weight ratio, permeability index (PPI), total leukocytes and polymorphonuclear neutrophils (PMNs) counts in bronchoalveolar lavage fluid (BALF), myeloperoxidase (MPO) and superoxide dismutase (SOD) activity, tumor necrosis factor (TNF)-α and interleukin (IL)-10 in lung and BALF were determined. Results: Pre-treatment with mannose attenuated pulmonary edema and protein exudation in a dose-dependent manner, the maximal effect was similar to or greater than that of DXM. Mannose also prevented the inflammatory cell accumulation, although the maximal effect was weaker than that of DXM. Mannose was more effective than DXM in inhibiting MPO activity and restoring SOD activity. Moreover, it inhibited production of TNF-α and IL-10. Histological changes of the lungs were also ameliorated by mannose. There were no significant improvements observed in rats pre-treated with glucose, galactose or fructose. Conclusions: Mannose is effective in reducing LPS-induced ALI. Project supported by the National Natural Science Foundation of China, No. 30670930 and the Science and Technology Department of Zhejiang Province (No.2004C23011) Received 4 March 2007; returned for revision 13 May 2007; returned for final revision 17 July 2007; accepted by M. Katori 12 September 2007     

Tripterygium hypoglaucum (level) Hutch induces aneuploidy of chromosome 8 in mouse bone marrow cells and sperm

Aneuploidy of mouse chromosome 8 induced by a Chinese medicinal herb, Tripterygium hypoglaucum (level) Hutch (THH) was investigated by fluorescence in situ hybridization (FISH) in vivo. Male mice were treated with THH (single i.p. injection) at doses of 120, 240 and 480 mg/kg. Colchicine (COL, 1.5 mg/kg i.p.) was used as a positive control. Bone marrow cells and epididymal sperm were collected 24 h and 22 days after treatment, respectively. Chromosome 8 aneuploidies induced by THH in bone marrow cells and sperm were determined by FISH with a biotin-16-dUTP labelled DNA probe corresponding to the centromeric region of chromosome 8. The hybridized probe was detected with avidin-FITC. The frequencies of trisomy 8 in bone marrow cells were 0.16% in the solvent control group, 0.39% in the COL-treated group and 0.33, 0.41 and 0.41% in the THH-treated groups, respectively. The frequencies of disomy 8 sperm were 0.11% in the solvent control group, 0.27% in the COL-treated group and 0.23, 0.27 and 0.27% in the THH-treated groups, respectively. The experiment showed that induced aneuploidy frequencies were higher in bone marrow cells than in sperm with COL and the two higher doses of THH (P < 0.05). All groups were significantly different from the corresponding solvent controls (P < 0.01-0.001), but there was no dose-related increase in either cell type. Considering the present results together with our previous studies, it appears that THH is a potent mammalian aneugen which may pose a genetic risk to human patients.     

高压氧中毒小鼠脑微血管图像分析定量研究

本文采用计算机图像定量测量方法，对高压氧中毒后小鼠软脑膜微血管和大脑皮质毛细胞血管内皮细胞碱性磷酶活性进行了定量检测。结果表明，ＨＢＯＩ后小鼠软脑膜毛细血管开放数目减少，毛细血管密度降低。     

亚低温减少大鼠短暂性全脑缺血后皮质iNOS诱导的神经元凋亡

为研究亚低温对大鼠脑缺血再灌注后皮质iNOS表达、NO产生及神经元凋亡的影响及探讨亚低温的神经保护机制,用大鼠短暂全脑缺血模型,采用Nissl染色观察存活神经元、免疫组化法检测iNOS、硝酸还原酶法检测NOx-水平和TUNEL染色结合电子显微镜观察检测凋亡神经元。结果显示:常温缺血组额叶皮质iNOS表达、NOx-水平增高,出现凋亡神经元;低温缺血组iNOS表达、NOx-水平明显低于常温缺血组,未检测到凋亡神经元。上述结果提示,脑缺血后iNOS来源的NO参与了神经元的凋亡过程,亚低温可减少大鼠短暂性全脑缺血后iNOS诱导的神经元凋亡。     

Immunological responses against SARS-coronavirus infection in humans

Since the outbreak of a SARS epidemic last year, significant advances have been made on our understanding of the mechanisms of interaction between the SARS coronavirus (CoV) and the immune system. Strong humoral responses have been found in most patients following SARS-CoV infection, with high titers of neutralizing Abs present in their convalescent sera. The nucleocapsid (N) and spike (S) proteins of SARS-CoV appear to be the dominant antigens recognized by serum Abs. CD4+ T cell responses against the N protein have been observed in SARS patients and an HLA-A2-restricted cytotoxic T lymphocyte epitope in the S protein has been identified. It is likely that the immune responses induced by SARS-CoV infection could also cause pathological damage to the host, especially in the case of proinflammatory cytokines. There is also evidence suggesting that SARS-CoV might be able to directly invade cells of the immune system. Our understanding on the interaction between SARS-CoV, the immune system and local tissues is essential to future diagnosis, control and treatment of this very contagious disease.     

医学图像无损压缩与有损压缩技术的进展

本文对医学图像无损压缩和有损压缩的概念和应用进行了分析比较 ,并简要介绍了几种近年来发展的图像无损压缩方法 ,重点介绍了有损压缩中的小波图像压缩技术和分形图像压缩技术。在医学图像的压缩中 ,通过有效地结合无损压缩和有损压缩技术 ,可以在得到医学要求的图像保真度的前提上 ,达到较高的压缩比     

白细胞介素4基因转移的肿瘤细胞体外生物学特性及体内致瘤性的研究

观察了白细胞介素４（ＩＬ－４）基因转移的肿瘤细胞体内致瘤性的变化。构建了含５００ｂｐ的小鼠ＩＬ－４ｃＤＮＡ的真核表达载体ＢＭＧＮｅｏ－ＩＬ－４．用该表达载体将ＩＬ－４基因转移至小鼠Ｂ１６黑色素瘤细胞，通过Ｇ４１８抗性筛选、有限稀释法及ＩＬ－４活性检测，获得了高分泌ＩＬ－４的黑色素瘤细胞克隆株并经Ｎｏｒｔｈｅｒｎ印迹鉴定，将其接种于小鼠皮下后观察到肿瘤生长缓慢、小鼠存活期延长，表明高分泌ＩＬ－４的细胞克隆株体内致瘤性显著下降。该结果为进一步研究肿瘤的ＩＬ－４基因治疗打下了基础。     

干扰素－α对兔离体的卵巢颗粒细胞孕酮生成的影响

本研究应用离体培养的兔卵巢颗粒细胞观察了ＩＦＮ－ａ对孕酮生成的影响。细胞预培养２４ｈ后，用ＩＦＮ－ａ（５０～８００Ｕ／ｍｌ）处理培养的颗粒细胞１２ｂ刺激孕酮的生成并呈剂量依赖关系。在ＩＦＮ－ａ加入培养细胞后３、１２和２４ｈ．刺激作用非常明显，但刺激作用的幅度在３和１２ｈ较大，分别为对照组的２４和２０倍。此外，ＩＦＮ－ａ刺激离体兔颗粒细胞孕酮生成的作用被同时加钙螫合剂ＥＧＴＡ（１ｍｍｏｌ／Ｌ）或钙通道阻断剂异搏定（ｖｅｒ）２０和２００μｍｏｌ／Ｌ所抑制。本研究结果表明，ＩＦＮ－ａ刺激离体兔卵巢颗粒细胞孕酮的生成，其作用依赖于细胞外的Ｃａ２＋浓度。     

Fourier变换形状测试法测量关节面形状

本文应用富里叶变换形状测试技术（ＦＴＰ），针对人体关节测试研究，并从实际应用角度分析了ＦＴＰ技术的误差及其改进方法，对标准平板和标准圆柱面的测定结果表明，精度可以达到０．０５ｍｍ以上。