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841.
Deregulated inhibition of apoptosis (programmed cell death) may facilitate the insurgence of neoplasia, but whether it also influences the outcome of common cancers has remained controversial. In this study, we investigated the expression of a novel inhibitor of apoptosis, survivin, in colorectal cancer and its relationship with tumor cell apoptosis and overall prognosis. By immunohistochemistry, survivin was expressed in 91 of 171 (53.2%) cases of colorectal carcinomas of histological stages 0 to IV. In contrast, normal colon epithelium did not express survivin. Although survivin expression did not correlate with p53 abnormalities (46.5% versus 58.0%; P = 0.18), survivin-positive cases were strongly associated with bcl-2 expression (72.5% versus 27.4%; P < 0.0001) and reduced apoptotic index (0.76% +/- 0.39% versus 1.17% +/- 0.62%; P < 0.0001). Expression of survivin alone in bcl-2-negative (discordant) cases also resulted in reduced apoptotic index (0.82% +/- 0.57% versus 1.16% +/- 0.66%; P = 0.0046). When analyzed for prognostic significance, patients with low apoptotic index (< 0.97%) had worse survival rates than the group with high apoptosis (P < 0.001), and a multivariate Cox proportional hazard model identified reduced apoptosis as an independent predictive factor for overall survival (P < 0.0001). These data demonstrate that apoptosis inhibition by survivin, alone or in cooperation with bcl-2, is an important predictive/prognostic parameter of poor outcome in colorectal carcinoma and identify survivin as a new diagnostic/therapeutic target in cancer.  相似文献   
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845.
There are seven porphyrias which are caused by defective functions of the enzymes in the haem biosynthesis. The clinical classification of porphyrias are divided into three types which are neuroporphyria, neurocutaneous porphyria and cutaneous porphyria. For acute porphyric attack of neuroporphyria and neurocutaneous porphyria, the treatments of choice are administration of glucose and/or hematin, haem arginate and tinprotoporphyrin. Porphyria cutanea tarda in cutaneous porphyria is controlled by removal of iron by phrebotomies or low-dose chloriquine. A novel approach of intravenous administration of interferon may be useful to control the associated case of chronic hepatitis type C. Skin symptoms in erythropoietic protoporphyria can be alleviated with beta carotene. Hepatic failure due to protoporphyria may need a liver transplantation. Cimetidine, a H2-receptor antagonist, may be useful in the treatment of acute porphyric attack and in remission stage in neuroporphyrias, neurocutaneous porphyrias and cutaneous porphyrias such as porphyria cutanea tarda and protoporphyria.  相似文献   
846.
Biomanufacturing     
Biomedical markets are large and rapidly growing owing to increasing demand for better healthcare services. The development of innovative biomedical systems can produce major breakthroughs in the healthcare industry, and advanced manufacturing technologies can propel such innovations. This paper summarises the field of biomanufacturing: namely, biospecific design constraints, biomechatronics, biofabrication, biodesign, and assembly. This paper presents state-of-the-art research, current problems, and future goals while providing fundamental knowledge required for entry into the biomedical industry. Biomanufacturing provides excellent opportunities for multi-disciplinary collaborations, both in academia and industry, and can lead to further advances in many engineering fields.  相似文献   
847.
  总被引:1,自引:0,他引:1  
ABSTRACT: A bacterium, which was isolated from fish-sauce mush (moromi) of frigate mackerel and identified as Staphylococcus xylosus , could change notes of an odor in fish sauce made in Thailand. Volatile compounds of the fish sauce after incubation at 32 °C for 24 d with the cultured bacterium were analyzed by gas chromatogra-phy. Although the contents of 2-ethylpyridine and dimethyl trisulfide were reduced during the incubation, 4 volatile compounds, including 2-methylpronal, 2-methylbutanal, 2-pentanone, and 3-(methylthio)propanal, showed no significant quantity changes. On the other hand, although 3-methyl-1-butanol and 2,6-dimethylpyrazine were markedly increased, 3-methylbutanoic acid was slightly increased. As a result of sensory evaluation, fishy, sweaty, fecal, and rancid notes of the fish sauce treated with the bacterium were all weaker than those of the nontreated fish sauce. No changes were found with respect to burnt, cheesy, meaty, and ammoniacal notes between fish sauce treated with the bacterium and that without treatment. Taken together, the odor of fish sauce was much improved by treatment with the isolated bacterium.  相似文献   
848.
    
Abstract— A solution‐processed organic thin‐film‐transistor array to drive a 5‐in.‐diagonal liquid‐crystal display has been fabricated, where semiconductor films, a gate dielectric film, and passivation films have all been formed using solution processes. A field‐effect mobility of 1.6 cm2/V‐sec, which is among the highest for solution‐processed organic thin‐film transistors ever reported, was obtained. This result is due to semiconductor material with large‐grain‐sized pentacene crystals formed from a solution and adoption of three‐layered passivation films that minimize the performance degradation of organic thin‐film transistors.  相似文献   
849.
    
Abstract — We achieved operationally stable white OLEDs with a single solution processed EML fabricated using a self‐layered technique. An LT70 of 10 khr at an initial luminance of 1000 cd/m2 was obtained by suppressing the exciplex formation between the EML and ETL, preventing Li diffusion into the EMLs, and using red dopants with shallow LUMO levels and stable host materials.  相似文献   
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