所谓加权即重点突出某方面的特性。之所以要加权是因为在一般的成像过程中，组织的各方面特性（如：质子密度、T值、T值）均对MR信号有贡献，几乎不可能得到仅纯粹反映组织一种特性的MR图像，通过利用成像参数的调整，使图像主要反映组织某方面特性，而尽量抑制组织其他特性对MR信号的影响，这就是"加权"。T加权成像是指这种成像方法重点突出组织纵向弛豫差别，而尽量减少组织其他特性如横向弛豫等对图像的影响；T加权成像重点突出组织的横向弛豫差别；质子密度加权像则主要反映组织的质子含量差别。

关于TWI的叙述正确的是

A:长T的组织呈低信号 B:脂肪呈高信号 C:短T的组织呈低信号 D:脑脊液呈低信号 E:骨骼呈高信号

患者女，57岁。胆总管结石。入院行胆总管切开探查，T型管引流术。

术后针对T型管引流的护理措施，不妥的是

A:记录引流胆汁的量、色及性状 B:每日用生理盐水冲洗T型管 C:一般留置2周 D:拔管前经T管胆道造影 E:拔管前夹管观察1~2天

ε（3-t）ε（t）=（）

A:ε（t）-ε（t-3） B:ε（t） C:ε（t）-ε（3-t） D:ε（3-t）

During the past 15 years, the most important component of executive pay packages, and the one most responsible for the large increase in the level of such compensation, has been stock-option grants. The increased use of option grants was justified as a way to align executives’ interests with shareholders’. For various tax, accounting, and regulatory reasons, stock-option grants have largely comprised "at-the-money options": fights to purchase shares at an "exercise price" equal to the company’s stock price on the grant date. In such at-the-money options, the selection of the grant date for awarding options determines the options’ exercise price and thus can have a significant effect on their value.
Earlier research by financial economists on backdating practices focused on the extent to which the company’s stock price went up abnormally after the grant date. My colleagues and I focused instead on how a grant-date’s price ranked in the distribution of stock prices during the month of the grant. Studying the universe of about 19,000 at-the-money, unscheduled grants awarded to public companies’ CEOs during the decade 1996-2005, we found a clear relation between the likelihood of a day’s being selected as a grant date for awarding options, and the rank of the day’s stock price within the price distribution of the month: a day was most likely to be chosen if the stock price was at the lowest level of the month, second most likely to be chosen if the price was at the second-lowest level, and so forth. There is an especially large incidence of "lucky grants" (defined as grants awarded on days on which the stock price was at the lowest level of the month): 12 percent of all CEO option grants were lucky grants, while only 4 percent were awarded at the highest price of the month.
The passage of the Sarbanes-Oxley Act in August 2002 required firms to report grants within two days of any award. Most firms complied with this requirement, but more than 20 percent of grants continued to be reported after a long delay. Thus, the legislation could be expected to reduce but not eliminate backdating. The patterns of CEO luck are consistent with this expectation: the percentage of grants that were lucky was a high 15 percent before enactment of the law, and declined to a lower, but still abnormally high, level of 8 percent afterwards.
Altogether, we estimate that about 1,150 CEO stock-option grants owed their financially advantageous status to opportunistic timing rather than to mere luck. This practice was spread over a significant number of CEOs and firms: we estimate that about 850 CEOs (about 10 percent) and about 720 firms (about 12 percent) received or provided such lucky grants. In addition, we estimate that about 550 additional grants at the second-lowest or third-lowest price of the month owed their status to opportunistic timing.
The cases that have come under scrutiny thus far have led to a widespread impression that opportunistic timing has been primarily concentrated in "new economy" firms. But while the frequency of lucky grants has been somewhat higher in such firms, more than 80 percent of the opportunistically timed grants have been awarded in other sectors. Indeed, there is a significantly higher-than-normal incidence of lucky grants in each of the economy’s 12 industries.
The result of the author’s study shows that

A:stock options are more likely to be awarded when prices are low. B:there is a vague relationship between stock options and grant price. C:there is a clear relationship between lucky grants and lucky dates. D:stock options are only awarded when the price is at the lowest.

During the past 15 years, the most important component of executive pay packages, and the one .most responsible for the large increase in the level of such compensation, has been stock-option grants. The increased use of option grants was justified as a way to align executives’ interests with shareholders’. For various tax, accounting, and regulatory reasons, stock-option grants have largely comprised "at-the-money options": rights to purchase shares at an "exercise price" equal to the company’s stock price on the grant date. In such at-the-money options, the selection of the grant date for awarding options determines the options’ exercise price and thus can have a significant effect on their value.
Earlier research by financial economists on backdating practices focused on the extent to which the company’s stock price went up abnormally after the grant date, My colleagues and I focused instead on how a grant-date’s price ranked in the distribution of stock prices during the month of the grant. Studying the universe of about 19,000 at-the-money, unscheduled grants awarded to public companies’ CEOs during the decade 1996-2005, we found a clear relation between the likelihood of a day’s being selected as a grant date for awarding options, and the rank of the day’s stock price within the price distribution of the month: a day was most likely to be chosen if the stock price was at the lowest level of the month, second most likely to be chosen if the price was at the second-lowest level, and so forth. There is an especially large incidence of "lucky grants" (defined as grants awarded on days on which the stock price was at the lowest level of the month): 12 percent of all CEO option grants were lucky grants, while only 4 percent were awarded at the highest price of the month.
The passage of the Sarbanes-Oxley Act in August 2002 required firms to report grants within two days of any award. Most firms complied with this requirement, but more than 20 percent of grants continued to be reported after a long delay. Thus, the legislation could be expected to reduce but not eliminate backdating. The patterns of CEO luck are consistent with this expectation: the percentage of grants that were lucky was a high 15 percent before enactment of the law, and declined to a lower, but still abnormally high, level of 8 percent afterwards.
Altogether, we estimate that about 1,150 CEO stock-option grants owed their financially advantageous status to opportunistic timing rather than to mere luck. This practice was spread over a significant number of CEOs and firms: we estimate that about 850 CEOs ( about 10 percent) and about 720 firms ( about 12 percent) received or provided such lucky grants. In addition, we estimate that about 550 additional grants at the second-lowest or third-lowest price of the month owed their status to opportunistic timing.
The cases that have come under scrutiny thus far have led to a widespread impression that opportunistic timing has been primarily concentrated in "new economy" firms. But while the frequency of lucky grants has been somewhat higher in such firms, more than 80 percent of the opportunistically timed grants have been awarded in other sectors. Indeed, there is a significantly higher-than-normal incidence of lucky grants in each of the economy’s 12 industries.
The result of the author’s study shows that

A:stock options are more likely to be awarded when prices are low. B:there is a vague relationship between stock options and grant price. C:there is a clear relationship between lucky grants and lucky dates. D:stock options are only awarded when the price is at the lowest.

A recent poll indicated that half the teenagers in the United States believe that communication between them and their parents is (1) and further that one of the prime causes of this gap is (2) listening behavior. As a(an) (3) in point, one parent believed that her daughter had a severe (4) problem. She was so (5) that she took her to an audiologist to have her ear tested. The audiologist carefully tested both ears and reported back to the parent:"There’s nothing wrong with her hearing. She’s just (6) you out. "
A leading cause of the (7) divorce rate (more than half of all marriages end in divorce) is the failure of husbands and wives to (8) effectively. They don’t listen to each other. Neither person (9) to the actual message sent by the other.
In (10) fashion, political scientists report that a growing number of people believe that their elected and (11) officials are out of (12) with the constituents they are supposedly (13) Why Because they don’t believe that they listen to them. In fact, it seems that sometimes our politicians don’t even listen to themselves. The following is a true story: At a national (14) conference held in Albuquerque some years ago, then Senator Joseph Montoya was (15) a copy of a press release by a press aide shortly before he got up before the audience to (16) a speech. When he rose to speak, (17) the horror of the press aide and the (18) of his audience, Montoya began reading the press release, not his speech. He began, "For immediate release. Senator Joseph M. Montoya, Democrat of New Mexico, last night told the National... " Montoya read the entire six page release, (19) with the statement that he "was repeatedly (20) by applause. /

A:distributed B:awarded C:handed D:submitted

During the past 15 years, the most important component of executive pay packages, and the one most responsible for the large increase in the level of such compensation, has been stock-option grants. The increased use of option grants was justified as a way to align executives’ interests with shareholders’. For various tax, accounting, and regulatory reasons, stock-option grants have largely comprised " at-the-money options", rights to purchase shares at an "exercise price" equal to the company’s stock price on the grant date. In such at-the-money options, the selection of the grant date for awarding options determines the options’ exercise price and thus can have a significant effect on their value.
Earlier research by financial economists on backdating practices focused on the extent to which the company’s stock price went up abnormally after the grant date. My colleagues and I focused instead on how a grant-date’s price ranked in the distribution of stock prices during the month of the grant. Studying the universe of about 19,000 at-the-money, unscheduled grants awarded to public companies’ CEOs during the decade 1996-2005, we found a clear relation between the likelihood of a day’s being selected as a grant date for awarding options, and the rank of the day’s stock price within the price distribution of the month: a day was most likely to be chosen if the stock price was at the lowest level of the month, second most likely to be chosen if the price was at the second-lowest level, and so forth. There is an especially large incidence of "lucky grants" ( defined as grants awarded on days on which the stock price was at the lowest level of the month) : 12 percent of all CEO option grants were lucky grants, while only 4 percent were awarded at the highest price of the month.
The passage of the Sarbanes-Oxley Act in August 2002 required firms to report grants within two days of any award. Most firms complied with this requirement, but more than 20 percent of grants continued to be reported after a long delay. Thus, the legislation could be expected to reduce but not eliminate backdating. The patterns of CEO luck are consistent with this expectation: the percentage of grants that were lucky was a high 15 percent before enactment of the law, and declined to a lower, but still abnormally high, level of 8 percent afterwards.
Altogether, we estimate that about 1,150 CEO stock-option grants owed their financially advantageous status to opportunistic timing rather than to mere luck. This practice was spread over a significant number of CEOs and firms: we estimate that about 850 CEOs (about 10 percent) and about 720 firms (about 12 percent) received or provided such lucky grants. In addition, we estimate that about 550 additional grants at the second-lowest or third-lowest price of the month owed their status to opportunistic timing.
The cases that have come under scrutiny thus far have led to a widespread impression that opportunistic timing has been primarily concentrated in " new economy" firms. But while the frequency of lucky grants has been somewhat higher in such firms, more than 80 percent of the opportunistically timed grants have been awarded in other sectors. Indeed, there is a significantly higher-than-normal incidence of lucky grants in each of the economy’s 12 industries.
The result of the author’s study shows that

A:stock options are more likely to be awarded when prices are low. B:there is a vague relationship between stock options and grant price. C:there is a clear relationship between lucky grants and lucky dates. D:stock options are only awarded when the price is at the lowest.

A recent poll indicated that half the teenagers in the United States believe that communication between them and their parents is (1) and further that one of the prime causes of this gap is (2) listening behavior. As a(an) (3) in point, one parent believed that her daughter had a severe (4) problem. She was so (5) that she took her to an audiologist to have her ear tested. The audiologist carefully tested both ears and reported back to the parent:"There’s nothing wrong with her hearing. She’s just (6) you out. "
A leading cause of the (7) divorce rate (more than half of all marriages end in divorce) is the failure of husbands and wives to (8) effectively. They don’t listen to each other. Neither person (9) to the actual message sent by the other.
In (10) fashion, political scientists report that a growing number of people believe that their elected and (11) officials are out of (12) with the constituents they are supposedly (13) Why Because they don’t believe that they listen to them. In fact, it seems that sometimes our politicians don’t even listen to themselves. The following is a true story: At a national (14) conference held in Albuquerque some years ago, then Senator Joseph Montoya was (15) a copy of a press release by a press aide shortly before he got up before the audience to (16) a speech. When he rose to speak, (17) the horror of the press aide and the (18) of his audience, Montoya began reading the press release, not his speech. He began, "For immediate release. Senator Joseph M. Montoya, Democrat of New Mexico, last night told the National... " Montoya read the entire six page release, (19) with the statement that he "was repeatedly (20) by applause.

A:distributed B:awarded C:handed D:submitted