Every year, 2,000 American lives are saved by the selflessness of others. These are the bone marrow donors who give the gift of life to patients fighting deadly diseases such as leukemia, lymphoma, and aplastic anemia. That’s the good news. The bad news is that thousands more die each year because not enough people have signed on to the registries that would help the ill find a suitable match for a transplant.Bone marrow or stem-cell transplants are usually a last resort, intended for those whose illnesses have not responded to traditional treatments such as chemotherapy or radiation. How do they work We all store a special type of cell in our bone marrow called stem cells. These primitive cells give rise to the three types of blood cells: red, white and platelets. Everyone’s stem cells have certain genetic characteristics or markers that make them unique from others. Despite this uniqueness, there are some shared characteristics between people. This is important, because a patient’s immune system will reject blood or organs received from someone else if they do not share sufficient similarities.Family members, especially siblings, are always the first to be considered as donors, because there’s a greater chance that the genetic markers on their cells will have enough in common to prevent rejection after transplantation. In many cases, however, a familial match can’t be found and then the search begins for an unrelated donor. These donors typically come from a pool of people who have already signed up on a donor registry in the event that their cells match a needy recipient.Once the lab has verified a match between donor and recipient, the next phase starts. The patient is given radiation or chemotherapy to kill the unhealthy cells. Healthy cells are harvested from the donor—either extracted from the pelvic bones or taken from the arm in a way that is similar to having blood drawn—and prepared in a laboratory. Once they’re ready, they’re given to the patient through a vein—the same way as one would receive a blood transfusion. Once these transplanted donor cells get settled within the patient’s bone marrow, they make the healthy red blood cells, white blood cells and platelets necessary to support life.One of the major problems currently faced by transplant centers is that while bone marrow transplants can cure more than 70 different diseases, there aren’t enough donors on the registry to treat the more than 3,000 patients awaiting transplants. The National Marrow Donor Program, the largest registry in the country, has approximately 4.8 million adult volunteer donors, but that isn’t nearly enough for the thousands who need transplants.Why isn’t a pool of more than 4 million donors isn’t enough to cover 3,000 needy patients Here’s the reason: in the vast majority of cases, finding a suitable match isn’t easy. Because we are unique individuals with a variety of ancestral backgrounds and integration patterns, finding someone similar to us is a major task. In the end, it comes down to a numbers game—the more potential donors listed on the registry, the greater a chance of finding a match, especially for those with unusual genetic characteristics. Who are usually considered the best donors for bone marrow transplant().
A. Parents.
Brothers and sisters.
C. Registered donors.
D. Healthy donors.
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Like land, labor is means of production. In nonindustrial societies, access to both land and labor comes through social links such as kinship, marriage, and descent. Mutual aid in production is merely one aspect of ongoing social relationships that are expressed on many other occasions.Nonindustrial societies contrast with industrial nations in regard to another means of production—technology. In bands and tribes manufacturing is often linked to age and gender. Women may weave and men make pottery or vice versa. Most people of a particular age and gender share the technical knowledge associated with that age and gender. If married women customarily make baskets, most married women know how to make baskets. Neither technology nor technical knowledge is as specialized as it is in states.However, some tribal societies do promote specialization. Among the Yanomani of Benezuela and Brazil, for instance, certain villages manufacture clay pots and others make hammocks. They don’t specialize, as one might suppose, because certain raw materials happen to be available near particular village. Clay suitable for pots is widely available. Everyone knows how to make pots, but not everybody does so. Craft specialization reflects the social and political environment rather than the natural environment. Such specialization promotes trade, which is the first step in creating an alliance with enemy villages. Specialization contributes to keeping the peace, although it has not prevented inter-village warfare.Among the Trobriand Islanders of the South Pacific, Malinowski found that only two out of several villages manufactured certain ceremonial items that were important in a regional exchange network called the kula ring. As among the Yanomani, this specialization was unrelated to the location of raw materials. We don’t know why this specialization began, but we do know that it persisted within the kula ring, which allied several communities and island in a common trade network. In regard to technology, how do nonindustrial societies differ from industrial societies().
A. In nonindustrial societies, there is not any kind of specialization of technology.
B. In nonindustrial societies, technology is not as specialized as it is in industrial society.
C. In industrial societies, women do different jobs before and after marriage.
D. In industrial societies, people are more easily adapted to certain technical field.
In the United States the first day nursery was opened in 1854. Nurseries were established in various areas during the (31) half of the 19th century; most of (32) were charitable. Both in Europe and in the U.S., the day-nursery movement received great (33) during the First World War, when (34) of manpower caused the industrial employment of unprecedented numbers of women. In some European countries nurseries were established even in munitions plants, under direct government (35) . Although the number of nurseries in the U.S. also rose (36) , this rise was accomplished without government aid of any kind. During the years following the First World War, (37) , Federal, State, and local governments gradually began to (38) a measure of control in the day nurseries, chiefly by (39) them and by inspecting and regulating the conditions within the nurseries.The (40) of the Second World War was quickly followed by an increase in the number of day nurseries in almost all countries, as women were again (41) to replace men in the factories. On this (42) the U.S. government immediately came to the support of the nursery schools, (43) $6,000,000 in July, 1942, for a nursery-school program for the children of working mothers. Many states and local communities (44) this Federal aid. By the end of the War, in August, 1945, more than 100, 000 children were being cared (45) in daycare centers receiving Federal (46) . Soon afterward, the Federal government drastically (47) its expenditures for this purpose and later (48) them, causing a sharp drop in the number of nursery schools in operation. However, the expectation (49) most employed mothers would leave their jobs at the end of the War was only partly (50) . 44().
A. reinforced
B. strengthened
C. supplemented
D. compensated
The Importance of Tertiary Education You are to write in three parts. In the first part, state specifically what your opinion is. In the second part, provide one or two reasons to support your opinion. In the last part, bring what you have written to a natural conclusion or make a summary. Marks will be awarded for content, organization, language and appropriateness. Failure to follow the above instructions may result in a loss of marks.
The story that traces life from sea to land then into the multiple niches that exist there for a great variety of living things is a fascinating one, but far too detailed for our purposes. One key point for us in that story is the emergence of the biological class of animals that are called mammals.Mammals have a number of features that distinguish them from the reptiles from which they developed. They are warm-blooded; that is, they have a system of temperature control that keeps the body at a constant temperature. Mammals have a set of teeth of different shapes that serve different functions such as cutting, gouging, and grinding. Young mammals spend their earliest days of development shielded within the mother’s body and are then born alive, rather than hatching from eggs. In addition, after birth they are nourished by milk provided by the mother’s mammary glands. The enforced association between mother and infant provides an opportunity for learning that does not exist for those kinds of creatures that are hatched from eggs long after their parents have departed from the scene. Young mammals play—something that amphibians and reptiles never do—which provides additional learning opportunities.The foregoing list leaves little doubt that we are mammals. There are, of course, a great many kinds of mammals, most of which developed after the great extinction of dinosaurs and other reptiles about 65 million years ago that opened opportunities for the few small mammals that were already in existence. One of the groups of mammals that resulted was a biological order called primates which includes monkeys, apes, humans, and some smaller creatures familiar only to ardent zoo goers. Primates share a number of behavioral features that have played important roles in their evolutionary development. Most primates are arboreal; that is, they spend their lives in and among trees. Their tree-climbing and tree-dwelling habits impose needs that are reflected in primate anatomy. Although diet varies from species to species, many primates are largely vegetarian. But they can eat and digest meat, and some species vary theft diets of leaves, shoots, and fruits by eating insects, birds’ eggs, and even small animals. Primates are hand-feeders, depending on their hands both to collect food and to get it into their mouths. Perhaps the most important feature of their behavior is that primates are social animals. Their genetics, habits, and even their survival are geared to living in groups. Although human beings have come to have a way of life very different from that of typical primates, the basic primate adaptation provided prehumans with capabilities that allowed them to become culture-builders.The anatomical features that separate primates from other kinds of animals relate clearly to the way primates behave. Which of the following is NOT one of the features of mammals that distinguish them from the reptiles().
A. They’re warm-blooded.
B. They have a set of teeth of different shapes.
C. The first period of development of young mammals is within the mother’s body.
D. There’s some association between mother and infant.