单选题酶化学修饰调节最常见的方式是

单选题蛋白质一级结构的主要化学键是

单选题有机磷化合物中毒时抑制胆碱酯酶，此抑制属于

单选题体内唯一能清除氧自由基的抗氧化酶是（ ）

单选题血氨升高最主要的原因是

单选题The Supreme Court will hear arguments about the use of public money for the private schooling of children with special needs. It's interesting to note what's not at issue: namely, that when a public school system is unable to provide an appropriate education, it is obligated to pay the costs of private school. Too bad poor children don't have that unshakable right; if they did, there would be no controversy about the District program that gives vouchers to low-income children to attend private schools. The case to be heard by the court hinges on whether parents have to enroll a child with special needs in public school before the child can attend private school at public expense. Special-education advocates say students shouldn't have to waste time before being placed in a setting that best suits their needs, while school boards worry about a ruling that could amount to an unfettered fight to private schooling at public expense. What strikes us about the emotionally charged debate is the acceptance by both sides that sometimes it is appropriate to use public money to pay for a child to go to a private school. So, why all the arguments about the approximately$14 million for a federally funded program that lets 1,700 D. C. students attend private schools instead of failing public schools? To hear critics of the D. C. Opportunity Scholarship Program tell it, the use of public money for private schooling is as unprecedented as it is undesirable. In addition to the billions of dollars spent annually on private school tuitions for students with disabilities, private schools get public money for books, technology and teacher training. As long as the money is seen as benefiting the child, it is considered a proper, even desirable, use of public dollars. Don't get us wrong. We're not arguing for the unilateral right of parents to enroll their sons and daughters in any school they wish with the taxpayers picking up the bill. Abuse of special-education policies has contributed to increased costs that threaten to take needed money from general public education funds. Safeguards are needed. Public schools should be pressed to do a better job for students with disabilities and students without. But there are schools in Washington where statistics show that failure is almost guaranteed. If a school system can't educate a child—whether because of acute special needs or its own historical failings—why should that child not have options for a " free appropriate public education " ?

单选题维持蛋白质二级结构的主要化学键是（）。

单选题载脂蛋白的主要结构特征是含有较多的

单选题关于前导链叙述正确的是

单选题磷酸戊糖途径的生理意义，不包括

单选题不以胆固醇为原料的化合物是

单选题三羧酸循环中哪一个化合物前后各生成一个分子CO 2

单选题血浆中催化脂肪酰转移到胆固醇生成胆固醇酯的酶是

单选题DNA复制和转录过程具有许多异同点，下列关于DNA复制和转录的描述中哪项是不正确的

单选题酮体不能在肝中氧化的是肝中缺乏下列哪种酶

单选题She was French; he was English; they had just moved to London from Paris. When he found out about her affair, she begged for a reconciliation. He was more ruthless: the same afternoon, he filed for divorce in France, one of the stingiest jurisdictions in Europe for the non-earning spouse and where adultery affects the court's ruling. Had she filed first in England her conduct would have been irrelevant, and she would have had a good chance of a large share of the marital assets, and even maintenance for life. International divorce is full of such dramas and anomalies, so the natural response of policymakers is to try to make things simpler and more predictable. But the biggest attempt in recent years to do just that, in a European agreement called Rome Ⅲ, has just been shelved. Instead, several EU countries are now pressing ahead with their own harmonisation deal. Many wonder if it will work any better. At issue is the vexed question of which country's law applies to the break-up of a mixed marriage. The spouses may live long-term in a third country and be temporarily working in a fourth. The worst way to sort that out is with expensive legal battles in multiple jurisdictions. The main principle at present is that the first court to be approached hears the case. Introduced in 2001, this practice has worked well in preventing international legal battles, but has made couples much more trigger-happy, because the spouse who hesitates in order to save a troubled marriage may lose a huge amount of money. Rome III aimed to remove the incentive to go to court quickly. Instead, courts in any EU country would automatically apply the local law that had chiefly governed the marriage. This approach is already in force in countries such as the Netherlands. A couple that moved there and sought divorce having spent most of the marriage in France, say, would find a Dutch court dividing assets and handling child custody according to French law. That works fine among continental European countries where legal systems, based on Roman law, leave little role for precedent or the judge's discretion. You can look up the rules on a website and apply them. But it is anathema in places such as England, where the system favours a thorough (and often expensive) investigation of the details of each case, and then lets judges decide according to previous cases and English law. Another snag is that what may suit middle-class expatriates in Brussels (who just happened to be the people drafting Rome Ⅲ) may not suit, for example, a mixed marriage that has mainly been based in a country, perhaps not even an EU member, with" a sharply different divorce law. Swedish politicians don't like the idea that their courts would be asked to enforce marriage laws based on, say, Islamic sharia. The threat of vetoes from Sweden and like-minded countries has blocked Rome Ⅲ. But a group of nine countries, led by Spain and France, is going ahead. They are resorting to a provision in EU rules-never before invoked-called " enhanced co-operation" This sets a precedent for a "multi-speed'" Europe in which like-minded countries are allowed to move towards greater integration, rather than seeking a "big-bang" binding treaty that scoops up the willing and unwilling alike. Some countries worry that using enhanced co-operation will create unmanageable layers of complexity, with EU law replaced by multiple adhoc agreements. The real lesson may be that Rome III was just too ambitious. A more modest but useful goal would be simply to clarify the factors that determine which court hears a divorce, and then let that court apply its own law. David Hodson, a British expert, proposes an international deal that would start by giving greatest weight to any prenuptial agreement, followed by long-term residency, and then take into account other factors such as nationality. That would then make it easier to end marriages amicably, with mediation and out-of-court agreement, rather than a race to start the beastly business of litigation.

单选题与酶活性相关性小的金属离子是

单选题Rb基因和p53基因

单选题关于蛋白质四级结构的叙述，正确的是

单选题下列哪项不属于转录调节因子的结构