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The immune system is equal in complexity to the combined intricacies of the brain and nervous system. The success of the immune system in defending the body relies on a dynamic regulatory communications network consisting of millions and millions of cells. Organized into sets and subsets, these cells pass information back and forth like clouds of bees swarming around a hive. The result is a sensitive system of checks and balances that produces an immune response that is prompt, appropriate, effective and self-limiting. At the heart of the immune system is the ability to distinguish between self and non-self. When immune defenders encounter cells or organisms carrying foreign or non-self molecules, the immune troops move quickly to eliminate the invaders. Virtually every body cell carries distinctive molecules that identify it as self. The body’’s immune defenses do not normally attack tissues that carry a self marker. Rather, immune cells and other body cells coexist peaceably in a state known as self-tolerance. When a normally functioning immune system attacks a non-self molecule, the system has the ability to remember the specifics of the foreign body. Upon subsequent encounters with the same species of molecules, the immune system reacts accordingly. With the possible exception of antibodies passed during lactation ( 哺乳期 ), this so-called immune system memory is not inherited. Despite the occurrence of a virus in your family, your immune system must learn from experience with the many millions of distinctive non-self molecules in the sea of microbes in which we live. Learning necessitates producing the appropriate molecules and cells to match up with and counteract each non-self invader. Any substance capable of stimulating an immune response is called an antigen. Tissues or cells from another individual (except an identical twin, whose cells carry identical self-markers ) act as antigens; because the immune system recognizes transplanted tissues as foreign, it rejects them. The body will even reject nourishing proteins unless they are first broken down by the digestive system into their primary, non-antigenic building blocks. An antigen announces its foreignness by means of intricate and characteristic shapes called epitopes( 抗原决定基), which stick out from its surface. Most antigens, even the simplest microbes, carry several different kinds of epitopes on their surface, some may even carry several hundred. Some epitopes will be more effective than others at stimulating an immune response. Only in abnormal situations does the immune system wrongly identify self as non-self and execute a misdirected immune attack. The result can be so-called autoimmune disease. The painful side effects of these diseases are caused by a person’’s immune system actually attacking itself The remembering power of a person’’s immune system is
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Speech, whether oral or written, is a used commodity. If we are to be heard, we must (1) our words from those (2) to us within families, peer groups, societal institutions, and political networks. Our utterances position us both in an immediate social dialogue (3) our addressee and, simultaneously, in a larger ideological one (4) by history and society. We speak as an individual and also, as a student or teacher, a husband or wife, a person of a particular discipline, social class, religion, race, or other socially constructed (5) . Thus, to varying degrees, all speaking is a (6) of others’ words and all writing is rewriting. As language (7) , we experience individual agency by infusing our own intentions (8) other people’s words, and this can be very hard.(9) , schools, like into churches and courtrooms, are places (10) people speak words that are more important than they are. The words of a particular discipline, like those of "God the father" or of "the law," are being articulated by spokespeople for the given authority. The (11) of the addressed, the listener, is to acknowledge the words and their (12) . In Bakhtin’s (13) , "the authoritative word is located in a distanced zone, organically connected with a (14) that is felt to be hierarchally higher."(15) , part of growing up in an ideological sense is becoming more "selective" about the words we appropriate and, (16) , pass on to others. In Bakhtin’s (17) , responsible people do not treat (18) as givens, they treat them as utterances, spoken by particular people located in specific ways in the social landscape. Becoming alive to the socio-ideological complexity of language use is (19) to becoming a more responsive language user and, potentially, a more playful one too, able to use a (20) of social voices, of perspectives, in articulating one’s own ideas. Read the following text. Choose the best word(s) for each numbered blank and mark A, B, C or D on ANSWER SHEET 1.11（）
There will be a steady trend toward vegetarianism. A given quantity of ground can provide plant food for man or it can provide plant food for animals which are later killed for meat. In converting the tissues of food into the tissues of the feeder, up to 90 per cent is used for reasons other than tissue maintenance and growth. This means that one hundred pounds of plant food will support ten pounds of human tissue―while one hundred pounds of plant food will support ten pounds of animal tissue, which will then support one pound of human tissue. In other words, land devoted to plant food will support ten times as many human beings as land devoted to animal food. It is this (far more than food preferences or religious directions ) that forces overcrowded populations into vegetarianism. And it will be the direction in which the United States of 2001 will be moving―not by presidential order, but through the force of a steady rise in meat prices as compared with other kinds of food. This, in turn, will come about because our herds will decrease as the food demand causes more and more meadow to be turned to farmland, and as land producing corn and other animal food is converted to providing food directly for man. Another point is that it is not only energy that is in short supply. A shortage of oil means a shortage of plastics; a shortage of electricity means a shortage of aluminium. We are also experiencing a shortage of paper and most other raw materials. This means that, for one thing, our generosity in wrapping, bagging and packaging will have to recede. There will have to be at least a partial return in supermarkets to the old days where goods were supplied in bulk and given out in bags to order. It may even become necessary to return bags, as we once returned bottles, or pay for new ones. A decline in per-capita energy use will make it necessary to resort to human muscle again, so that the delivery man will make a comeback (his price added to that of the food, of course).Since energy shortages will cause unemployment in many sectors of the economy, there will be idle hands to do the manual work that will become necessary. From an energy-saving standpoint, it would make far more sense to order by phone and have a single truck deliver food to many homes, than for a member of each home to drive an automobile, round-trip, to pick up a one-family food supply. To be sure, it will not all be retrogression. Even assuming that Earth is in a desperate battle of survival through a crisis of still rising population and dwindling energy reserves, there should still continue to be technological advances in those directions that don’’t depend on wasteful bulk use of energy. There will be continuing advances in the direction of "sophistication", in other words. We know from the text that
[55～57]某箱形基础底面尺寸为20m×45m，基础底面埋深d=4.5m，地下水位在地面下2.5m处。地基土为均质粉土，黏粒含量13%，粉土的重度：地下水位以上γ=18.0kN/m3，地下水位以下γsat=19.00kN/m3。由现场载荷试验确定出地基承载力特征值为：fak=175kPa。上部结构传至箱形基础顶面的轴心荷载效应Fk=130.5MN。 地基基础设计时经修正后的地基承载力特征值最接近（）。
某房地产公司计划在北京开发某住宅项目，采用公开招标的形式，有A、B、C、D、E、F6家施工单位领取了招标文件。本工程招标文件规定：2009年1.0月20日下午17：30为投标文件接收终止时间。在提交投标文件的同时，需投标单位提供投标保证金20万元。 在2009年10月20日，A、B、C、D、F5家投标单位在下午17：30前将投标文件送达，E单位在次日上午8：00送达。各单位均按招标文件的规定提供了投标保证金。 在10月20日上午10：25时，B单位向招标人递交了一份投标价格下降5%的书面说明。 开标时，由招标人检查投标文件的密封情况，确认无误后，由工作人员当众拆封，并宣读了 A、B、C、D、F承包商的名称、投标价格、工期和其他主要内容。 在开标过程中，招标人发现C单位的标袋密封处仅有投标单位公章，没有法定代表人印章或签字。 评标委员会委员由招标人直接确定，共有4人组成，其中招标人代表2人，经济专家1人，技术专家1人。 招标人委托评标委员会确定中标人，经过综合评定，评标委员会确定A单位为中标单位。 问题： 在招标投标过程中有何不妥之处说明理由。
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