问题 单项选择题 A1/A2型题

肝硬化腹水产生的最主要原因是()

A.血清白蛋白降低

B.门静脉压力增高

C.肾功能不全

D.脾功能亢进

E.便秘

答案

参考答案:B

解析:腹水是多种因素综合作用的结果,门静脉高压是水分潴留在腹腔的主要原因。门静脉高压时,肝窦静水压升高(门脉压力>10mmHg,是腹水形成的基本条件),大量液体流到Disse间隙,造成肝脏淋巴液生成过多。当胸导管不能引流过多的淋巴液时,就从肝包膜直接漏入腹腔形成腹水。选项A血清白蛋白降低,血浆胶体渗透压降低,血管内液外渗,促使腹水的形成,但不是主要原因;选项C肾功能不全时,肾小球滤过率降低,排钠、排尿量减少,也是形成腹水的原因之一;选项D、E与肝硬化腹水产生无直接关系。

填空题
单项选择题

The food you eat does more than provide energy. It can have a dramatic effect on your body’s ability to fight off heart disease, cancer, diabetes, high blood pressure, stroke, and weak bones. With remarkable consistency, recent research has found that a diet high in plant-based foods—fruits, vegetables, dried peas and beans, grains, and starchy staples such as potatoes—is the body’s best weapon in thwarting many health-related problems. These foods work against so many diseases that the same healthy ingredients you might use to protect your heart or ward off cancer will also benefit your intestinal tract and bones.

Scientists have recently estimated that approximately 30 to 40 percent of all cancers could be averted if people ate more fruits, vegetables, and plant-based foods and minimized high-fat, high-calorie edibles that have scant nutritional value. Up to 70 percent’ of cancers might be eliminated if people also stopped smoking, exercised regularly, and controlled their weight. In the past, researchers had linked fat consumption with the development of cancers, but they currently believe that eating fruits, vegetables, and grains may be more important in preventing the disease than not eating fat. "The evidence about a high-fat diet and cancer seemed a lot per several years ago than it does now," says Melanie Polk, a registered dietitian and director of nutrition education at the American Institute for Cancer Research.

The road to p bones is paved with calcium-rich food. Leafy green vegetables and low-fat dairy products are excellent sources of calcium, the mineral that puts stiffness into your skeletal system and keeps your bones from turning rubbery and fragile. Your body uses calcium for more than keeping your bones p. Calcium permits cells, to divide, regulates muscle contraction and relaxation, and plays an important role in the movement of protein and nutrients inside cells. If you don’t absorb enough from what you eat to satisfy these requirements, your body will take it from your bones. Because your body doesn’t produce this essential mineral, you must continually replenish the supply. Even though the recommended daily amount is 1,200mg, most adults don’t eat more than 500mg. One reason may have been the perception that calcium-rich dairy products were also loaded with calories. "In the past, women, in particular, worried that dairy products were high in calories," says Letha Y. Griffin, M. D. , of Peachtree Orthopaedics in Atlanta. "But today you can get calcium without eating any high-fat or high-calorie foods by choosing skim milk or low-fat yogurt." Also, low-fat dairy products contain phosphorous and magnesium and are generally fortified with vitamin D, all of which help your body absorb and use calcium. If you find it difficult to include enough calcium in your diet, ask your doctor about supplements. They’re a potent way to get calcium as well as vitamin D and other minerals. But if you rely on pills instead of a calcium-rich diet, you won’t benefit from the other nutrients that food provides. Getting the recommended vitamin D may be easy, since your body makes the vitamin when your skin is exposed to the sun’s rays.

According to the passage, cancers may take some healthy steps other than()

A. stop smoking

B. exercise regularly

C. take non-fat diet

D. control their weight