Effects of aflatoxin B1 on human skin lipids metabolism — a site of action on 1-14C-acetate incroporation

Zusammenfassung Aflatoxin B₁ hemmt den Einbau von 1-¹⁴C-Azetat in die Lipide der menschlichen Haut. Wird aber³H-Azetyl-CoA als Vorstufe für den Lipideinbau verwendet, so kommt es zu keiner merklichen Hemmung. Die Azetataktivierung scheint somit die wichtigste, vom Toxin beeinflussbare Stufe der Lipidsynthese zu sein.     

Loss of Cul1 results in early embryonic lethality and dysregulation of cyclin E.

The sequential timing of cell-cycle transitions is primarily governed by the availability and activity of key cell-cycle proteins. Recent studies in yeast have identified a class of ubiquitin ligases (E3 enzymes) called SCF complexes, which regulate the abundance of proteins that promote and inhibit cell-cycle progression at the G1-S phase transition. SCF complexes consist of three invariable components, Skp1, Cul-1 (Cdc53 in yeast) and Rbx1, and a variable F-box protein that recruits a specific cellular protein to the ubquitin pathway for degradation. To study the role of Cul-1 in mammalian development and cell-cycle regulation, we generated mice deficient for Cul1 and analysed null embryos and heterozygous cell lines. We show that Cul1 is required for early mouse development and that Cul1 mutants fail to regulate the abundance of the G1 cyclin, cyclin E (encoded by Ccne), during embryogenesis.     

琅琊山森林群落演替预测

本研究把中心点——四分面和我们提出的“树冠权重更新面积”(TCWRA)结合起来,运用于野外植被资料的取样。在此基础上,用Markov过程描述了琅琊山森林群落线性和非线性演替,预测了平衡时群落空间各层次林木的组成状态。研究结果表明,琅琊山森林群落在没有外界大的干扰下,麻栎、化香种群将从该群落中消退,发展成以青檀、五角枫、榉树为优势种群的顶极群落。     

用光度法测求混配络合物(水杨酸乙二胺合铜(Ⅱ))的稳定常数

在μ=0.1(M).T=20.0±0.5℃的条件下,研究了铜(Ⅱ)与水杨酸、乙二胺之间的络合反应,并用光度法结合pH测量,求得了混配络合物(水杨酸乙二胺合铜(Ⅱ))的稳定常数β_(111):lgβ_(111)=18.9。又用pH电位滴定法对此结果进行了检验,在相同的条件下测得lgβ_(111)=18.85。这两个结果相当一致。     

Subgroup-specific structural variation across 1,000 medulloblastoma genomes

Medulloblastoma, the most common malignant paediatric brain tumour, is currently treated with nonspecific cytotoxic therapies including surgery, whole-brain radiation, and aggressive chemotherapy. As medulloblastoma exhibits marked intertumoural heterogeneity, with at least four distinct molecular variants, previous attempts to identify targets for therapy have been underpowered because of small samples sizes. Here we report somatic copy number aberrations (SCNAs) in 1,087 unique medulloblastomas. SCNAs are common in medulloblastoma, and are predominantly subgroup-enriched. The most common region of focal copy number gain is a tandem duplication of SNCAIP, a gene associated with Parkinson's disease, which is exquisitely restricted to Group 4α. Recurrent translocations of PVT1, including PVT1-MYC and PVT1-NDRG1, that arise through chromothripsis are restricted to Group 3. Numerous targetable SCNAs, including recurrent events targeting TGF-β signalling in Group 3, and NF-κB signalling in Group 4, suggest future avenues for rational, targeted therapy.     

The Behavior of the Rotor Spun Yarn(OE yarn)with Involving Twist

The rotor spun yarn(OE yarn),twist of which is calledlayering twist,was added a few involving twist,and itsstructure and properties were measured.The experimen-tal results have shown that the morphological structure ofthe rotor spun yarn with modified twist was changed andits tensile properties and abrasion resistance were im-proved.     

体外震波碎石术治疗尿路结石(附146例报告)

1991年5月至1992年5月,我院采用国产NE-Ⅳ型碎石机对146例尿路结石患者进行了229人次的原位碎石治疗。碎石成功率为98.63％,碎石术后3个月内肾上盏及肾盂排石率为68.99％,输尿管下段排石率为72.3％。本组结果表明,体外震波碎石治疗尿路结石安全、有效、并发症少。提高碎石疗效在于准确地B超定位及合理地选择适应症。     

Investigation in Longitudinal Compression of Wool Based Suiting Fabrics

This paper describes an investigation in the fabric longi-tudinal compressibility of thirty-one suiting and trouse-ring materials using a newly developed device attached to the advanced Instron extensometer Model4466.The at-tachment was designed mainly to ensure a correct align-meat of fabric plane at the start of compression.Usingthe newly developed testing method,fabric longitudinalcompression curve was obtained and the results of longi-tudinal compressibility measured by two different com-pression load ranges(from 0 to 0.5 N/m width and 0 to1 N/m width)were examined.In addition,their rela-tionships with the fabric low-stress mechanical proper-ties measured by the KES-F system were investigatedusing statistical analysis.The results clearly indicatedthat significant differences existed when substituting fab-ric longitudinal compressibility with fabric extensibilitymeasured using the KES-F system under a low-load.Significant infiuence of yarn rotational movement in fab-ric on the longitudinal compressibi