大鼠急性氧中毒后全脑细胞能量代谢的活体^31P磁共振谱 …

目的：探讨大鼠急性氧中毒后脑的能量代谢产物与脑细胞内ＰＨ变化的规律。方法：采用磁共振方法,用４．７Ｔ动物磁共振谱仪,检测氧中毒后不同时程各种磷酸化合物与无机磷酸根（Ｐｉ）、磷酸肌酸（ＰＣｒ）与γ－ＡＴＰ以及β－ＡＴＰ与Ｐｉ之间的比值,并根据Ｐｉ的化学位移推算脑细胞内ＰＨ值。结果：氧中毒组物舱１和３小时后ＰＣｒ／Ｐｉ,ＰＣｒ／γ－ＡＴＰ以及β－ＡＴＰ／Ｐｉ值均显著降低;５ｈ后恢复正常;２４和４８小时     

Dysregulation of apoptosis: a possible mechanism leading to chronic progressive renal histological changes in lupus nephritis

Objective To evaluate apoptosis in lupus nephritis and the relationship between the existe nce of apoptotic cells in renal tissue and histopathological or clinical changes .Methods Apoptosis was detected by in situ nick-end labeling techniques (TUNEL) in renal biopsies from 25 patients with type Ⅳ lupus nephritis (LN), 12 patients with I gA nephropathy IgAN, 4 patients with idiopathic mesangioproliferative glomerulon ephritis (MsPGN) and 3 patients with acute poststreptococcal glomerulonephritis (APGN).Normal renal tissue obtained at nephrectomy for hypernephroma in 4 adul ts was used as control.Proliferating cells were identified by proliferating ce ll nuclear antigen (PCNA) in these patients. Results Compared to other proliferative glomerulo-nephritis and controls, the patients w ith lupus nephritis had less apoptotic cells, a higher ratio of PCNA+ cells/TdT+ cells (P/T) in renal tissues; and their P/T ratio in glomeruli and tubuloin terstitium correlated with the chronicity index, r=0.4983 (P=0.0132), r=0.8399 (P<0.001), r=0.6614 (P=0.0033), respectively.P/T ratios in the glomerulus and tubule had a positive correlation with 24-hour uri nary protein, r=0.8554 (P<0.001) and r=0.7134 (P=0.001); and a negative correlation with creatinine clearance (Ccr), r=-0.4880 (P=0 .0133) and r=-0.7229 (P=0.001), which in tubules positively corre lated with serum creatinine (Scr), r=0.4107 (P=0.0414).Conclusions Apoptosis is reduced in proliferative lupus nephritis.Intense proliferation wi thout a commensurate increase in apoptosis is a possible mechanism that leads to chronic progressive renal histopathological changes.     

急性脑梗塞的红细胞膜流动性及生化指标改变

目的 探讨急性脑梗塞（ＡＣＩ）的发病机制及治疗措施。方法 采用测定ＡＣＩ患者血浆粘度,纤维蛋白原含量,红细胞膜荧光偏振度Ｐ,过氧化脂质水平,超氧化物歧化酶活性等指标进行对比研究。结果 与同龄健康组比较,ＡＣＩ患者ηｐ,Ｆｇ,ＬＰＯ水平均显著升高,ＳＯＤ活性显著降低。红细胞膜流动性下降。     

Nondomain biopolymers: Flexible molecular strategies to acquire biological functions

A long-standing assumption in molecular biology posits that the conservation of protein and nucleic acid sequences emphasizes the functional significance of biomolecules. These conserved sequences fold into distinct secondary and tertiary structures, enable highly specific molecular interactions, and regulate complex yet organized molecular processes within living cells. However, recent evidence suggests that biomolecules can also function through primary sequence regions that lack conservation across species or gene families. These regions typically do not form rigid structures, and their inherent flexibility is critical for their functional roles. This review examines the emerging roles and molecular mechanisms of “nondomain biomolecules,” whose functions are not easily predicted due to the absence of conserved functional domains. We propose the hypothesis that both domain- and nondomain-type molecules work together to enable flexible and efficient molecular processes within the highly crowded intracellular environment.     

流行性出血热患者早期免疫应答的研究

应用反向被动血凝集抑制试验和血凝集抑制试验检测流行性出血热患者早期血清（７病日内）中病毒核蛋白、膜蛋白抗体。１０３例患者血清,仅核蛋白抗体出现者３３例,病情转径及无变化者３１例（９３．９４％）．而转重者仅２例（６．０６％）,且其血清抗体主要为ＩｇＧ型。仅膜蛋白抗体出现的患者９例,病情转重者８例（８８．８９％）,其抗体主要为ＩｇＭ．核蛋白、膜蛋白抗体均阳性的６１例患者,病情转归介于上述二者之间．提示：核蛋白抗体先出现的患者,病情多转轻,而膜蛋白抗体先出现的患者,病情普遍转重,似与病毒的＂一次性打击＂有关。在仅核蛋白抗体出现的患者中,有２例病情转重,但其抗体球蛋白类型为ＩｇＧ,故尚不能排除本病有＂二次感染＂的可能,这一现象在推行本病预防接种时值得重视,另对进一步探讨本病的发病机理及预测患者的病情转归亦具参考价值。     

Selective incorporation of111In-labeled PHOTOFRIN™ by glioma tissuein vivo

The use of PHOTOFRIN for photodynamic therapy of human gliomas has been studied by i.v. administration and laser photosensitization. Defining the uptake of PHOTOFRIN in the patient's tumor in comparison with the surrounding normal brain tissue is highly desirable for patient selection and study ofin vivo kinetics. We utilized a non-invasive approach to the detection of PHOTOFRIN uptake in brain tumors with¹¹¹In-oxine radiolabeled PHOTOFRIN and external imaging and quantitation using a gamma camera. Biodistribution of¹¹¹In-labeled PHOTOFRIN in 13 organs was determined in four dogs and 15 mice with gliomas.^99mTc-DTPA was used as a control for nonspecific uptake. The greatest concentration of¹¹¹In-PHOTOFRIN in the brain tumor occurred at 24 hours post i.v. administration. The brain tumor PHOTOFRIN uptake was seven times greater than that of normal brain. The decreased blood background at 72 hours made this the optimum time for imaging. Specific tumor tissue uptake of¹¹¹In-PHOTOFRIN occurred, well beyond that resulting from blood-brain-barrier (BBB) breakdown.     

The anti-proliferative effect of proliferating cell nuclear antigen-specific antisense oligonucleotides on human gastric cancer cell lines

The proliferating cell nuclear antigen (PCNA) is a nuclear protein that leads DNA synthesis by the DNA polymerase delta. As the PCNA gene is strongly expressed in invasive gastric cancer cells with high proliferative activity, PCNA is suspected of playing an important role in the proliferation and advancement of gastric cancer. Thus, the effects of antisense oligonucleotides specific for PCNA mRNA were examined in seven gastric cancer cell lines. It was found that treatment with antisense oligonucleotides at concentrations of 10–40 M dose-dependently inhibited the growth of all cell lines; however, random sequence oligonucleotides did not modify the proliferation of any type of cells. These results indicate that PCNA is essential for cell proliferation in gastric cancer cells, and that the growth inhibitory effect results from the inhibition of PCNA gene expression. Therefore, PCNA-specific antisense oligonucleotides may be effective in the treatment of gastric cancer.     

PCNA和C—erbB—2在喉癌中的表达以及临床意义

用免疫组化ＳＰ法对６３例喉鳞状细胞癌的ＰＣＮＡ和Ｃ－ｅｒｂＢ－２进行原位检测,并随访了５年的生存情况。结果表明,ＰＣＮＡ指数越高,病理分级越差（Ｐ＜０．０１）,５年生存率越低（Ｐ＜０．０５）,颈淋巴结转移率越高（Ｐ＜０．０５）。而Ｃ－ｅｒｂＢ－２表达阳性率与病理分级、５年生存率及颈淋巴结转移率无关。ＰＣＮＡ和Ｃ－ｅｒｂＢ－２之间无相关性。提示ＰＣＮＡ指数与喉癌恶性程度、５年生存率、颈淋巴结转移率密切相关,在喉癌中检测ＰＣＮＡ较Ｃ－ｅｒｂＢ－２更有意义。     

尼龙1010／6及尼龙1010／66动态力学分析

通过动态力学参数温度谱,研究了尼龙１０１０／６、尼龙１０１０／６６两个共聚物系列的动态力学参数与组成的关系。研究表明尼龙１０１０／６、尼龙１０１０／６６在测试温度范围内出现三个明显的松驰转变：α、β、γ,其中各共聚物的β、γ松驰温度相差不大,而α松驰温度随组成改变有明显改变。一般均聚物的α松驰温度较高,共聚物的α松驰温度均低于均聚物,二个系列以尼龙１０１０／６（２９．８／７０．２）、尼龙１０１０／     

动态硫化PP／EPDM强化增韧机理的动态力学研究

采用动态力学试验方法,研究了不同ＥＰＤＭ含量的动态硫化和简单共混两种ＰＰ／ＥＰＤＭ材料动态力学响应的差异及其特征。结果显示：与简单共混ＰＰ／ＥＰＤＭ相比,动态硫化ＰＰ／ＥＰＤＭ具有ΔＴｇ小,内耗峰扩宽程度大,低温和室温内耗峰强度高,所处温度低,６０－７０℃时内耗峰强度发生高低变位,在ＥＰＤＭ相的α转变以下还显示β和γ次级转变等特性。