血清壁细胞抗体阳性多见于
A．慢性浅表性胃炎
B．慢性萎缩性胃窦胃炎
C．慢性萎缩性胃体胃炎
D．胃溃疡
E．胃癌
参考答案：C
解析：血清壁细胞抗体阳性多提示慢性萎缩性胃体胃炎。萎缩性胃炎分为两型：A型病变主要见于胃体部，多弥漫性分布，胃窦黏膜一般正常，血清壁细胞抗体阳性，血清胃泌素增高，胃酸和内因子分泌减少或缺少，易发生恶性贫血，又称为自身免疫性胃炎。B型萎缩性胃炎病变多见于胃窦部，呈多灶性分布，血清壁细胞抗体阴性，血清胃泌素多正常，胃酸分泌正常或轻度降低，无恶性贫血，较易并发胃癌，这是一种单纯性萎缩性胃炎。另外，病变同时累及胃窦、胃体的萎缩性胃炎称为AB型。
[考点] 血清壁细胞抗体阳性的意义。
| The first 50 years of the next millennium will be critical for the world’s population. By 2050 population growth should have leveled off, but by then we’ll have 10 billion people -- two-thirds as many again as we have today. The rate of population growth is something we can choose right now, though it’s not something that just happens, but a matter of human choice. The choice is a complicated one, with many variables, but it remains a choice. If we want to prevent a population explosion, we should take action now -- or assist the poorer countries to do so. They need better government, better institutions, better labor and capital markets, better schools. Anything that increases the value of women’s time and adds to the cost of caring for a child makes a woman less likely to have that child. Since big families are often seen as safety nets for illness and old age, improving poor people’s access to insurance, pensions and welfare institutions also has a major impact. This can be as simple as rural credit, providing a means of saving. Finally, there is education -- both for women and, perhaps even more important, for the next generation of children. These steps are there to be taken, but there appear to be some countries that are not seriously trying at the moment. If we cannot achieve that we will certainly not control population. That said, I don’t feel pessimistic that we are going to run out of resources: we are becoming more efficient at producing food faster than the rate at which population is increasing. There is, however, a risk that we will wreck the environment so effectively that the world will no longer be an attractive place to live. That really would be a dismal outcome, to reach world population equilibrium only to find we’d destroyed the natural environment in the process. |
By 2050, the population growth will ______.
A．rise steeply
B．fall sharply
C．come to a halt
D．remain even