问题 单项选择题

鼻咽癌的病理类型中常被称为"下行型"鼻咽癌的是()

A.高分化鳞状细胞癌

B.中分化鳞状细胞癌

C.泡状核细胞癌

D.未分化癌

E.囊腺癌

答案

参考答案:C

解析:高分化鳞状细胞癌早期侵犯颅底、鼻窦、颅神经等,较少出现颈部淋巴结转移,故常被称为"上行型"鼻咽癌,放疗敏感性差。泡状核细胞癌患者早期易出现颈部多个淋巴结转移,颅底侵犯少见,故被常称为"下行型"鼻咽癌。鼻咽未分化癌除了明显的局部颅内、外侵犯和广泛的淋巴结巨大转移外,易血行转移,故称为"上下行型"鼻咽癌。

单项选择题
单项选择题

In November the European Parliament’s culture and education committee is due to move forward on its proposed "audiovisual media services" directive, before sending it to the full parliament in December. The new rules update and relax the "Television Without Frontiers" directive of 1989, which opened Europe’s national markets. But critics complain that they also seek to extend fusty regulations from the era of broadcast television to today’s very different technologies. Rules on advertising, the protection of children and so on could potentially also apply to all kinds of video streams, including video blogs, online games and mobile-video services.

This could have a chilling effect on innovation and risks stifling emerging technologies with rules designed for another age, says Chris Marsden of RAND Europe, a think-tank that has analysed the potential impact of the proposed rules for Ofcom, Britain’s media and telecoms regulator. "Regulators have to be thoughtful. They cannot predict the future of television "or the internet—no one can," says Niklas Zennstr. m, a co-founder of Skype, who is now setting up an internet television firm.

The proposed rules may be unrealistic as well as onerous. The idea that websites can be regulated like broadcasters, which are required to keep strict records of what they show in order to help watchdogs investigate complaints, is untenable. Firms could simply relocate outside the European Union to escape the new rules. Last week Ruth Hieronymi, a member of parliament, said she would introduce wording that might help to overcome some of the objections.

Behind the debate is the question of how best to balance competition and protection. Traditional broadcasters worry that they will be shackled by regulations while brisk start-ups can do as they please—so they like the idea of extending regulation to their new rivals. But even if the rules are approved as they stand, they will not come into force until 2010. Such a long, slow process seems incongruous given the pace of technological change.

According to the text, the new rules()

A. seek to revise the previous regulation

B. complained by many educators

C. passed by European Parliament in 1989

D. opened Europe’s national markets