鞑靼滨藜挥发性化学成分分析

对鞑靼滨藜全草的挥发性化学成分进行分析。采用水蒸气蒸馏法及索氏提取法提取鞑靼滨藜全草中的挥发性化学成分,用GC-MS联用技术分析其化学组成,计算其相对百分含量,并对两种提取方法进行比较研究。结果表明:水蒸气蒸馏法提取物的成分比索氏提取法较多。从水蒸气蒸馏法分离出的53个色谱峰中鉴定了51种成分,含量最高的是茴香脑(45.84%),其次为正二十七烷(9.28%),羟基吲哚(6.81%),α-羟基-2-甲基丙基苯乙酸酯(4.03%)。从索氏提取法分离出的26个色谱峰中鉴定了22种成分,含量最高的是正二十九烷(22.63%),其次为硬酯酸(16.69%),十六醛(6.89%),棕榈酸(5.43%)。     

关联维数法在皮肤激光散斑测量中的应用

本文采用关联维数方法研究了皮肤厚度对皮肤激光散斑测量的影响。计算了６种模拟皮肤厚度情况下的生物散斑关联维数。结果表明,维数随皮肤厚度的增加而减小,而且重复性很好。这说明,关联维数方法可以应用在皮肤激光散斑的研究中     

Mayak worker study: an improved biokinetic model for reconstructing doses from internally deposited plutonium

The plutonium production facility known as the Mayak Production Association was put into operation in June 1948. A high incidence of cancer in the Mayak workers has been related to the level of exposure to plutonium, but uncertainties in tissue doses have hampered development of dose-risk relationships. As part of an effort to improve dose estimates for these workers, the systemic biokinetic model for plutonium currently recommended by the International Commission on Radiological Protection (ICRP) has been modified to reflect recently developed data and facilitate interpretation of case-specific information. This paper describes the proposed model and discusses its implications for dose reconstruction for the Mayak workers.     

Integration,expression and inheritance of transgenes in hexaploid oat (Avena sativa L.)

Two oat varieties, Melys (spring variety) and Bulwark (winter variety) were transformed by particle bombardment of primary embryogenic callus using either a ubi-bar-ubi-gus co-integration vector or co-transformed (Melys) with a ubi-bar plasmid together with one of three plasmids containing the beta-glucuronidase (gus) gene under the control of either a rice actin promoter, a CaMV35S promoter or a wheat high molecular weight glutenin promoter. Morphologically normal and fertile transgenic plants were regenerated following callus selection with glufosinate ammonium. Evidence for the integration and functioning of the selectable (bar) and reporter (gus) genes in T0 and T1 plants was confirmed by PCR, Southern hybridisation, fluorescence in situ hybridisation (FISH), histochemical assays, and by progeny analysis. Transformation rates varied from 0.2 to 5.0 lines/plate of callus bombarded, with co-transformation frequencies of 83 to 100%, and co-expression frequencies of 60 to 100%. Copy numbers for the bar and gus gene varied from 3 to 17 and from 2 to 20 respectively. Cell and tissue specific expression of the gus gene was evident from the different promoters, with the HMW glutenin promoter showing endosperm specific expression in T1 seed. No expression of the gus gene under the CaMV35S promoter was detected in any tissues. Progeny analysis provided evidence of Mendelian inheritance of the introduced genes suggesting either one or two unlinked integration sites. This was confirmed by fluorescence in situ hybridisation to chromosome spread preparations. No segregation of the gus gene from the bar gene was observed in any of the progeny derived from co-transformation.     

The effect of vitamin E on the response of rabbit bladder smooth muscle to hydrogen peroxide

There is increasing evidence that ischemia, reperfusion, and the generation of free radicals are major etiological factors in the progression of bladder dysfunction after partial outlet obstruction. In vitro studies demonstrated that the magnitude of contractile dysfunction following exposure of bladder smooth muscle to hypoxia followed by re-oxygenation was related to the level of lipid peroxidation indicating that membrane lipid peroxidation participated in the contractile failure induced. Recent studies demonstrated that incubation of isolated strips of bladder smooth muscle with hydrogen peroxide (H₂O₂) result in progressive contractile dysfunctions and is associated with progressive increases in MDA (peroxidation product). The current study investigates if feeding rabbits a diet high in vitamin E protects the bladder from the effects of in vitro H₂O₂. Sixty-four male New Zealand White rabbits were separated into two groups: The rabbits in group 1 were fed a normal diet (28 rabbits) whereas the rabbits in group 2 were placed on a diet enriched with -tocopherol (36 rabbits). After 3 weeks on the normal or high E diet, each rabbit was anesthetized and the bladder excised and cut into 6 isolated strips of bladder detrusor. Each strip was mounted in individual 15 ml baths containing oxygenated Tyrode's solution. The contractile responses to field stimulation (FS), carbachol, and KCl were determined. The strips were washed and exposed to one of the following concentrations of hydrogen peroxide (H₂O₂): 0% (control), 0.0625, 0.125, 0.25, 0.5, 1.0 and 3.0% for a period of 1 h. At the end of the hour each strip was washed free of H₂O₂ and a second set of contractile responses were performed and compared to the first set. At the end of the experiment, each strip was frozen and stored at –70°C for analysis of malondialdehyde (MDA) as a measure of peroxidation. In both groups, H₂O₂ produced similar dose dependent decreases in the contractile responses to all forms of stimulation. In the normal-diet group H₂O₂ produced a dose dependent increase in MDA formation, whereas in the high E group there were no increases in MDA at any concentration of H₂O₂. Feeding rabbits a diet high in vitamin E protected the bladder smooth muscle from peroxidation, but had no significant effect on the contractile dysfunctions mediated by direct incubation with H₂O₂.     

Anti-α-fodrin antibodies do not add much to the diagnosis of Sjögren's syndrome

The presence of anti-α-fodrin autoantibodies has been reported to be a highly specific and sensitive test for the diagnosis of Sjögren's syndrome (SjS). We looked (in Nijmegen) for anti-α-fodrin, anti-Ro60, and anti-La autoantibodies in a cohort of 51 patients with rheumatic diseases (primary SjS [21], secondary SjS [6], rheumatoid arthritis [RA] [12], systemic lupus erythematosus [SLE] [6], and scleroderma [6]) and in 28 healthy subjects, using ELISA, immunoblotting, and immunoprecipitation. The same samples were analyzed with an alternative anti-α-fodrin ELISA in Hanover. The Nijmegen ELISA of the sera from primary SjS showed sensitivities of 43% and 48% for IgA- and IgG-type anti-α-fodrin antibodies, respectively. The Hanover ELISA showed sensitivities of 38% and 10% for IgA- and IgG-type anti-α-fodrin antibodies, respectively. The ELISAs for α-fodrin showed six (Nijmegen) and four (Hanover) anti-α-fodrin-positive RA sera. IgA and IgG anti-fodrin antibodies were also present in four patients with secondary SjS. The sensitivities of Ro60 and La-antibodies in the Nijmegen ELISA were 67% and 62%, respectively. Unlike anti-α-fodrin antibodies, all anti-Ro60 and anti-La positive sera could be confirmed by immunoblotting or RNA immunoprecipitation. Thus, anti-Ro and anti-La autoantibodies were more sensitive than anti-α-fodrin autoantibodies in ELISA and were more frequently confirmed by other techniques. Anti-La antibodies appear to be more disease-specific than anti-α-fodrin antibodies, which are also found in RA sera. Therefore, the measurement of anti-α-fodrin autoantibodies does not add much to the diagnosis of Sjögren's syndrome.     

Uptake of bovine IgG by first instars of the common cattle grub, Hypoderma lineatum

The midgut of first instar Hypoderma lineatum (De Vill.) (Diptera: Oestridae) was examined for the presence of bovine immunoglobulin using immuno-gold staining in conjunction with image analysis. Newly hatched larvae, unexposed to fluids or tissues of the host, showed little or no deposit of colloidal gold particles. Midgut lumen, microvillar border, epithelial cell bodies and basement membrane of first instars, 6-7 months of age, recovered from the host oesophagus, all showed colloidal gold staining. This indicates that immuno-reactive portions of bovine immunoglobulin survive exposure to extracorporeal larval enzymes, as well as transit of the midgut, and pass through epithelial cells to enter the larval haemocoel.     

塔里木盆地西北缘核桃坚果生化成分多样性分析

该研究收集新疆塔里木盆地西北缘44份核桃资源,其中树龄超过50 a的实生资源41份、主栽良种3个,并对其主要生化成分蛋白质、糖、脂肪、氨基酸、油酸、亚油酸、亚麻酸、棕榈酸、硬脂酸进行了多样性分析。结果表明:44份资源的生化成分变异幅度大,存在着丰富的多样性。各指标变异幅度由4.93%~30.93%,香农-维纳指数(H')变幅为1.38~2.02。17种氨基酸变异幅度由10.07%~35.71%,香农-维纳指数(H')变幅为1.85~2.20。主要生化成分主成分分析显示蛋白质、糖、脂肪三个主要成分的累计贡献率达81.67%。聚类分析表明,群组间生化成分存在显著差异,群组的聚类与地理分布有明显相关性,流域相同的资源的生化成分构成比例具有相似性。与主栽品种相比,实生资源在糖、蛋白质、脂肪等方面具有更高的变异幅度,因而具有一定的开发潜力。     

Thick and thin fingers point out Turing waves

Mouse genetics and computer simulations demonstrate that digit number and width are controlled by a Turing-type mechanism in which distal Hox genes modulate periodicity.     

Effect of bilateral in vivo ischemia/reperfusion on the activities of superoxide dismutase and catalase: Response to a standardized grape suspension

Purpose: Ischemia/reperfusion (I/R) is a major etiological factor in the bladder dysfunctions observed in men with lower tract obstruction, women with postmenopausal incontinence and with aging. A standardized grape suspension protects the rabbit urinary bladder from both the contractile dysfunctions and the morphologic changes mediated by I/R. Using a model of in vivo bilateral ischemia/reperfusion, the current study investigated the effect of this grape suspension on the endogenous antioxidant defense systems. Materials and methods: 24 NZW rabbits were separated into 6 groups of 4. Groups 1–3 were treated by gavage with aqueous grape suspensions; groups 4–6 received sugar-water vehicle. Groups 3 and 6 were controls. Groups 1 and 4 were subjected to bilateral ischemia for 2 h (I). Groups 2 and 5 underwent bilateral ischemia for 2 h and reperfusion for 1 week (I/R). For all rabbit bladders, the muscle and mucosa were separated by blunt dissection and analyzed separately. The effects of the various treatments on bladder antioxidant systems of cytoplasmic superoxide dismutase (Cu-Zn superoxide dismutase; SOD), and catalase (CAT) were evaluated. Results: The standardized grape suspension up-regulated both SOD and CAT activity of bladder muscle and mucosa in control animals. There were few differences in the grape suspension treated animals after ischemia, and in general the activities decreased following I/R. Conclusions: Increases of SOD and CAT activity in control animals as a result of grape suspension suggest a greater antioxidant capacity. This increase in the antioxidant defense system may explain the increased protection of grape suspension in the face of ischemia and I/R. However, the activities of both enzyme systems decreased in the smooth muscle subjected to I/R showing that reperfusion damages these systems probably via oxidation damage to the enzymes themselves.