辅助

①HIV抗体初筛试验(ELISA)：敏感性高，可有假阳性出现。对于初筛阳性的患者，应经确证试验确证。②HIV抗体确证试验(WB)：WHO规定，只要出现2个env条带即可判定为阳性。③HIV-RNA：敏感性为100%，但偶尔会出现假阳性，但假阳性结果通常低于2000cp/ml，而急性感染期病毒载量通常很高，平均在106cp/ml。④p24抗原：有助于早期诊断，灵敏性及特异性均较高。⑤快速检测试验：可采集全血或毛细血管的血液，一般15-30分钟可出结果。但假阳性及假阴性率均较高，不作为常规检测。

艾滋病是一种可以累及全身各个器官的疾病，因此总体上可能会涉及到所有种类的血液检查、排泄物、分泌物、体液检查(包括尿液、粪便、痰液、肺泡灌洗液、脑脊液、胸水、腹水)、骨髓检查及针对不同部位、不同种类的并发症的影像学检查(包括各部位的超声、X线、CT、MRI、PET-CT)，活组织病理或细胞学检查(对肿瘤，分支杆菌、真菌、巨细胞病毒等感染的诊断及鉴别意义重大)。以上检查需要针对每名患者的不同并发症进行选择性检查。

需要特别提到的是，各期的患者，无论病情是否稳定，均需要监测CD4+ T淋巴细胞计数和HIV-RNA，以便及时开始抗病毒治疗和抗病毒用药调整。

Think carefully about the issue presented in the following excerpt and assignment below.

To change is to risk something, making us feel insecure. Not to change is a bigger risk, though we seldom feel that way. There is no choice but to change. People, however, cannot be motivated to change from the outside. All of our motivation comes from within.

Adapted from Ward Sybouts,Planning in School Administration:A Handbook Assignment

What motivates people to change? Plan and write an essay in which you develop your point of view on this issue. Support your position with reasoning and examples taken from you reading,studies, experience, or observations.

Sample Essay - 6分范文

What motivates people to change is a relentless and innate desire for self-improvement. Rarely ever has history seen a man or society kick back, relax, and say Well that about does it. Not much else to do here! Within every person is the potential to achieve greatness in some form; be it athletically, mentally, spiritually. This inherent potential demands that people continue to explore and change both their environments and themselves throughout their lifes course. Never should a man be idle for too long. After acknowledging the changes a man has already made to his environment, the pursuit of self-improvement will once again stir within his soul and call him to action. This internal desire, this pursuit of challenge and perfection, does not prohibit man from being happy with his status and achievements. On the contrary, the device serves more to allow the man to constantly strive for greater change, newer innovation. What motivates people to change is the ongoing need to redefine peoples lives and identities to elevate them to higher levels of eminence and sucess.

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