Angiography is a radiographic procedure that employs x-rays of the blood vessels in the body to assist in diagnosing and treating a variety of ailments. The x-ray image, or angiogram, allows diagnosis of pathologies of the blood vessels such as blockages, stenosis (narrowing of the vessel), and other aberrations so that they can be treated. Angiography can be purely investigative, but it is commonly employed in combination with minimally invasive surgery or catheterization. In the angiography procedure, a venous ‘‘contrast,’’ or dye, is administered orally, anally,rift gold or by intravenous injection. This dye is a radiopaque substance that highlights the blood vessels in the x-ray.
Magnetic resonance angiography (MRA) does not rely on radioactive dye; rather it employs a specific sequence of radio waves to create the angiogram. The MRA is able to provide a detailed map of the patient’s vasculature without an enhancer, although enhancers such as the rare earth element gadolinium are sometimes used to make the images clearer and bolder. In therapeutic or interventional angiography, the possible treatment runs from surgery to less invasive processes such as angioplasty or catheterization. In angioplasty, a catheter containing a small balloon is guided through the blood vessels to the site of the obstruction. Once in place, the balloon is inflated in order to expand the constricted area of the vessel. The catheter can also be used to guide into place surgical ‘‘stents,’’ cylindrical mesh-like supports that keep the vessel open to the desired width. Over one million angioplasty procedures were performed in the U.S. in 2000 to prevent or treat myocardial infarction (heart attack).
Rudimentary angiography was developed not long after the x-ray came into clinical use. In 1896 in Vienna, Eduard Haschek and Otto Lindenthal took x-rays of the blood vessels in an amputated hand injected with a radiopaque substance. The radiopaque contrast agent of choice has changed over time, owing in part to the high toxicity of the earliest agents used. Common formulations of contrast agents used today include various acetrizoic acids, diatrizoic acids, iodamides, and methanesulfonic acids.
Angiography is employed today in a number of clinical situations. The most common procedures performed are cerebral angiography, thoracic aortography, pulmonary and bronchial arteriography, coronary arteriography, and angiography of the extremities. In celial and mesenteric angiography, these arteries in the abdomen are examined to diagnose gastrointestinal bleeding, aneurysm, or ischemia. In cerebral angiography the blood vessels of the brain are investigated in order to locate and treat of blood clots, aneurysms, tumors, and migraines. In coronary angiography the coronary arteries are investigated to detect vascular diseases such as heart disease, heart attack, and acute stroke. Renal angiography is of value in diagnosing kidney disease and renal failure. In the latter case, the physician uses hemodialysis catheters to divert blood from the neck and filter it through a hemodialysis machine. One problem with kidney angiography is that the contrast agent can be harmful to the kidneys if the patient already suffers from renal ailments. In ocular angiography either fluorescein or indocyanine green contrast helps to view various problems in the eye such as retinal failure.
Complications surrounding angiographic procedures can arise either from reactions to the contrast agent or from problems with the performance of the catheterization or surgery. Reactions to the contrast agent are generally mild, such as nausea, but serious allergic reactions do occasionally occur. Renal damage can occur regardless of previous problems because of the mild toxicity of most opaque media contrasts. Some contrasts have also caused minor drops in blood pressure and vasodilatation of the arteries. When a catheter is placed in the body, blood clots can form and block the vessel or a small particle can break loose and lead to embolization, a potentially deadly complication. Catheters can also tear or puncture blood vessels causing internal bleeding and an exacerbation of the already existing problem. Hematomas and hemorrhages may occur if there are any complications in the catheterization process.
As with other medical tests and procedures,rift gold the risks of angiography are generally outweighed by the benefits, as the angiogram provides specific and detailed clinical information that is invaluable in clinical diagnosis and intervention.
2011年4月20日星期三
Do internet language polls mean anything?
Many language sites use online language polls, either on site pages or in forums. Recently, someone posted a comment in one of ours asking why we have them,rift gold and I recently read a discussion in a forum about their validity. There are a number of issues about polls that are worth bearing in mind.
Sample size
I had already put up a poll asking whether they had any meaning. Statistically, the numbers suggest that voters think they are, with just under 75% saying they do. However, and here is one of the key issues, the sample size is very small. The largest poll we have at the time of writing has about a thousand votes, and most language polls, especially those in forums that get buried in a matter of days by new threads, generally have relatively few votes.
However, a small number of votes doesn't necessarily mean that they have no validity. Over 90% agree that I have known her .... ages should be completed with for rather than since. This is a decidedly uncontroversial question of English language usage and a large proportion voting one way can be taken as an accurate view.
Sample Bias
This site, like all ESL sites, will also have a sample bias as a large number of visitors are teachers and most of the rest are non-native speakers. In our poll on whether people say if I were or if I was, about two-thirds have chosen were. As both forms are correct, this is not a question of right or wrong, but that proportion does not necessarily reflect usage patterns throughout the native speaker population, where the numbers using was would probably be higher. Many teachers prefer the more formal use of the subjunctive here rather than the indicative, and many students are taught to use it. The poll is not giving out incorrect information, but it would be wrong to extrapolate too much from this and think it a picture of wider usage.
Poll Design
Sometimes the questions in polls have design flaws- they do not include all possibilities, sometimes by accident and other times by design, especially where the poll writer wants to see a particular result, or simply for fun, as in this meaningless poll.
Multiple Voting
One ESL forum I visited recently complained about multiple voting. On our site forum, multiple voting is virtually impossible as system only allows one vote per member, though many systems allow multiple votes. The polls that appear on our Student and Teacher pages are only susceptible to this if a person sees the same poll time some time after the originally voted, but as random polls from a huge selection are presented the chances are greatly reduced. If someone tries to vote a second time, they will not be allowed to, but if they tried again a few days later, they would be able to. Our Poll section keeps the polls forever and presents them randomly, so over time the effect of multiple voting is minimal.
We do not have polls because they believe that they will present an utterly accurate picture of usage, but because any time the page is opened, they throw up a random question about language that may well give the person viewing the page something to think about, and the fact that the votes are climbing steadily each day suggests that they are performing that function. Additionally,rift gold the information they provide can show correct answers where it is a simple correct/incorrect choice, even with a small number of votes cast, and can indicate some trends and patterns of usage, though the data should not be given too much weight. Some polls are simply designed to provoke thought- my answer to this one might change from day to day. Overall, I think they are useful things, as long as too much emphasis is not given to the results, and I like them.
Sample size
I had already put up a poll asking whether they had any meaning. Statistically, the numbers suggest that voters think they are, with just under 75% saying they do. However, and here is one of the key issues, the sample size is very small. The largest poll we have at the time of writing has about a thousand votes, and most language polls, especially those in forums that get buried in a matter of days by new threads, generally have relatively few votes.
However, a small number of votes doesn't necessarily mean that they have no validity. Over 90% agree that I have known her .... ages should be completed with for rather than since. This is a decidedly uncontroversial question of English language usage and a large proportion voting one way can be taken as an accurate view.
Sample Bias
This site, like all ESL sites, will also have a sample bias as a large number of visitors are teachers and most of the rest are non-native speakers. In our poll on whether people say if I were or if I was, about two-thirds have chosen were. As both forms are correct, this is not a question of right or wrong, but that proportion does not necessarily reflect usage patterns throughout the native speaker population, where the numbers using was would probably be higher. Many teachers prefer the more formal use of the subjunctive here rather than the indicative, and many students are taught to use it. The poll is not giving out incorrect information, but it would be wrong to extrapolate too much from this and think it a picture of wider usage.
Poll Design
Sometimes the questions in polls have design flaws- they do not include all possibilities, sometimes by accident and other times by design, especially where the poll writer wants to see a particular result, or simply for fun, as in this meaningless poll.
Multiple Voting
One ESL forum I visited recently complained about multiple voting. On our site forum, multiple voting is virtually impossible as system only allows one vote per member, though many systems allow multiple votes. The polls that appear on our Student and Teacher pages are only susceptible to this if a person sees the same poll time some time after the originally voted, but as random polls from a huge selection are presented the chances are greatly reduced. If someone tries to vote a second time, they will not be allowed to, but if they tried again a few days later, they would be able to. Our Poll section keeps the polls forever and presents them randomly, so over time the effect of multiple voting is minimal.
We do not have polls because they believe that they will present an utterly accurate picture of usage, but because any time the page is opened, they throw up a random question about language that may well give the person viewing the page something to think about, and the fact that the votes are climbing steadily each day suggests that they are performing that function. Additionally,rift gold the information they provide can show correct answers where it is a simple correct/incorrect choice, even with a small number of votes cast, and can indicate some trends and patterns of usage, though the data should not be given too much weight. Some polls are simply designed to provoke thought- my answer to this one might change from day to day. Overall, I think they are useful things, as long as too much emphasis is not given to the results, and I like them.
2011年4月19日星期二
Considering how much Sean McCorkle talked prior to his UFC 124 fight against Stefan Struve last year, RIFT Platinum it was a little surprising to see "Big Sexy" remain relatively quiet in the weeks leading up to his UFC Fight Night 24 fight against Christian Morecraft.
Sure, there were a few tweets and videos posted, rift gold but nothing close to the verbal assault he unleashed on Struve.
"I really just didn't want to go into reruns," McCorkle (10-1) said on Monday's episode of The MMA Hour. "I didn't want to do the same thing I did last time. I think you and I talked about that, how it might wear thin."
Amazingly, Morecraft (6-1) whose only fight in the UFC is an August loss to Struve, initiated the trash-talk after the fight was announced by posting a video on YouTube mocking McCorkle.
"Especially since it was going to take place on Internet, I was a little surprised. It was funny to me; it wasn't insulting. Of course, nothing insults me."
McCorkle is 1-1 in the UFC, and he is fully aware that a bad performance on Saturday night could lead to the end of his UFC run.
That's not to say that the organization hasn't treated him well thus far.
Rift Gold In fact, McMorkle was given his win bonus after his lackluster performance against Struve in December.
"They pay me more than they have to pay me. I got my win bonus against Struve, even though I didn't win or fight very well at all. They sent that to me anyway, hopefully they didn't care that I put that on blast."
McCorkle was never given a specific reason as to why he was given his win bonus for a first-round loss, RIFT Platinumbut he thinks it has something to do with the hype he generated prior to the fight.
"I talked to my agent about [why he received a win bonus], he said, Probably more for your hype than the way you fought.
"I expected nothing after that fight. rift goldI didn't expect any bonus, anything. It showed up a couple of days before Christmas."
So while he won't necessarily admit it, McCorkle seems to be taking the "let my fighting do the talking" approach this time around, even though he doesn't seem to be too fond of this fighting thing altogether.
"I'm just enjoying the ride while it's here. I enjoy everything but the fight. RIFT Platinum The fight kind of sucks, to be honest with you. I don't really enjoy getting punched, but everything else about being in the UFC is awesome."
Sure, there were a few tweets and videos posted, rift gold but nothing close to the verbal assault he unleashed on Struve.
"I really just didn't want to go into reruns," McCorkle (10-1) said on Monday's episode of The MMA Hour. "I didn't want to do the same thing I did last time. I think you and I talked about that, how it might wear thin."
Amazingly, Morecraft (6-1) whose only fight in the UFC is an August loss to Struve, initiated the trash-talk after the fight was announced by posting a video on YouTube mocking McCorkle.
"Especially since it was going to take place on Internet, I was a little surprised. It was funny to me; it wasn't insulting. Of course, nothing insults me."
McCorkle is 1-1 in the UFC, and he is fully aware that a bad performance on Saturday night could lead to the end of his UFC run.
That's not to say that the organization hasn't treated him well thus far.
Rift Gold In fact, McMorkle was given his win bonus after his lackluster performance against Struve in December.
"They pay me more than they have to pay me. I got my win bonus against Struve, even though I didn't win or fight very well at all. They sent that to me anyway, hopefully they didn't care that I put that on blast."
McCorkle was never given a specific reason as to why he was given his win bonus for a first-round loss, RIFT Platinumbut he thinks it has something to do with the hype he generated prior to the fight.
"I talked to my agent about [why he received a win bonus], he said, Probably more for your hype than the way you fought.
"I expected nothing after that fight. rift goldI didn't expect any bonus, anything. It showed up a couple of days before Christmas."
So while he won't necessarily admit it, McCorkle seems to be taking the "let my fighting do the talking" approach this time around, even though he doesn't seem to be too fond of this fighting thing altogether.
"I'm just enjoying the ride while it's here. I enjoy everything but the fight. RIFT Platinum The fight kind of sucks, to be honest with you. I don't really enjoy getting punched, but everything else about being in the UFC is awesome."
Federal health officials say more than 21,000 people got whooping cough last year, RIFT Platinum many of them children and teens. That's the highest number since 2005 and among the worst years in more than 50 years.
The new numbers were reported at a vaccine advisory committee meeting in Atlanta. Rift Gold Health experts are puzzled by the recent spike in cases. The vaccine against whooping cough is highly effective in children, and vaccination rates for kids are considered good.
The disease is very contagious and in rare cases can be fatal, rift gold especially for babies too young to be vaccinated. Whooping cough starts like a cold but leads to severe coughing that can last for weeks.
Copyright 2010 The Associated Press. The information contained in the AP news report may not be published, broadcast, RIFT Platinum rewritten or otherwise distributed without the prior written authority of The Associated Press. All active hyperlinks have been inserted by AOL.
The new numbers were reported at a vaccine advisory committee meeting in Atlanta. Rift Gold Health experts are puzzled by the recent spike in cases. The vaccine against whooping cough is highly effective in children, and vaccination rates for kids are considered good.
The disease is very contagious and in rare cases can be fatal, rift gold especially for babies too young to be vaccinated. Whooping cough starts like a cold but leads to severe coughing that can last for weeks.
Copyright 2010 The Associated Press. The information contained in the AP news report may not be published, broadcast, RIFT Platinum rewritten or otherwise distributed without the prior written authority of The Associated Press. All active hyperlinks have been inserted by AOL.
Pfizer Inc is hoping to release its experimental rheumatoid arthritis drug after successfully completing another stage of a clinical trial.
The trial showed that after six months of use, the drug, tofacitinib, RIFT Platinum significantly reduced the signs and symptoms of RA in patients compared to those who were given a placebo, Reuters reports. rift gold The drug worked to improve physical function at three months and resulted in a greater rate of disease remission at six months. No new safety signals were seen by the trial's completion.
If approved Damien Conover, RIFT Platinum an analyst at Morningstar, expects the drug to generate peak annual sales of about $2 billion.
Although previous trials showed that the drug raised bad cholesterol and liver enzyme levels in some patients, investors are still optimistic that the RA drug will be approved.
Rift Gold However, the potential for additional trials due to the U.S. Food and Drug Administration may slow down the process.
"We're in a climate where the FDA is very risk averse," said. "I think there is a strong likelihood we'll see delays, potentially the need for new trials."
Other RA drugs currently in the market are injectable treatments such as Humira,RIFT Platinum made by Abbott Laboratories, and Amgen Inc's Enbrel.
The trial showed that after six months of use, the drug, tofacitinib, RIFT Platinum significantly reduced the signs and symptoms of RA in patients compared to those who were given a placebo, Reuters reports. rift gold The drug worked to improve physical function at three months and resulted in a greater rate of disease remission at six months. No new safety signals were seen by the trial's completion.
If approved Damien Conover, RIFT Platinum an analyst at Morningstar, expects the drug to generate peak annual sales of about $2 billion.
Although previous trials showed that the drug raised bad cholesterol and liver enzyme levels in some patients, investors are still optimistic that the RA drug will be approved.
Rift Gold However, the potential for additional trials due to the U.S. Food and Drug Administration may slow down the process.
"We're in a climate where the FDA is very risk averse," said. "I think there is a strong likelihood we'll see delays, potentially the need for new trials."
Other RA drugs currently in the market are injectable treatments such as Humira,RIFT Platinum made by Abbott Laboratories, and Amgen Inc's Enbrel.
Heavyweight Sean McCorkle has been released from his UFC contract, the fighter confirmed with MMA Fighting on Friday.
The news was first reported by Five Ounces of Pain.
McCorkle (10-2) enjoyed a successful UFC debut in September, submitting Mark Hunt in just 67 seconds. RIFT Platinum However, things went downhill for the 34-year-old after that.
Thanks to some clever Internet marketing, McCorkle helped propel himself all the way to the co-main event of UFC 124 against Stefan Struve in just his second fight for the organization. Unfortunately for "Big Sexy," rift gold Struve defeated him via first-round TKO.
McCorkle then lost to Christian Morecraft via second-round submission at UFC Fight Night 24 last month.
When asked for a comment, McCorkle wrote via text message:
"I want to thank the UFC for giving me an opportunity that I had not earned,RIFT Platinum giving me very favorable match-ups, and hyping me far more than my talent warranted."
He then quickly added:
"Oh, I'm sorry, I thought was writing a statement for Matt Mitrione."
Nice to see McCorkle's sense of humor is still very much in tact.
Rift Gold
The news was first reported by Five Ounces of Pain.
McCorkle (10-2) enjoyed a successful UFC debut in September, submitting Mark Hunt in just 67 seconds. RIFT Platinum However, things went downhill for the 34-year-old after that.
Thanks to some clever Internet marketing, McCorkle helped propel himself all the way to the co-main event of UFC 124 against Stefan Struve in just his second fight for the organization. Unfortunately for "Big Sexy," rift gold Struve defeated him via first-round TKO.
McCorkle then lost to Christian Morecraft via second-round submission at UFC Fight Night 24 last month.
When asked for a comment, McCorkle wrote via text message:
"I want to thank the UFC for giving me an opportunity that I had not earned,RIFT Platinum giving me very favorable match-ups, and hyping me far more than my talent warranted."
He then quickly added:
"Oh, I'm sorry, I thought was writing a statement for Matt Mitrione."
Nice to see McCorkle's sense of humor is still very much in tact.
Rift Gold
2011年4月18日星期一
Welterweights Martin Kampmann and John Howard have verbally agreed to meet at UFC on Versus 4, says UFC president Dana White on UFC.com.
The event takes place at the Consol Energy Center in Pittsburgh on June 26, sandwiched in between the UFC 131: Lesnar vs. Rift Gold Dos Santos and UFC 132: Cruz vs. Faber events.
Kampmann (17-5) is coming off back-to-back losses, both ending in controversial decisions. Kampmann took a split decision loss to Jake Shields at UFC 121 in October that led to Shields earning a shot against champion Georges St-Pierre.RIFT Platinum Next, Kampmann lost a unanimous decision in March to Diego Sanchez in a UFC on Versus 3 fight where Kampmann landed more significant strikes and stopped 14 of 15 takedown attempts. Fighting exclusively for the UFC since August 2006, Kampmann owns a record of 8-4 within the promotion.RIFT Platinum
Like Kampmann, Howard (14-6) is also on a two-fight skid. However,rift gold Howard's losses have been clear defeats against Jake Ellenberger (doctor stoppage) and Thiago Alves (lopsided decision). Prior to the losses, Howard was victorious in his first four UFC fights.
The event takes place at the Consol Energy Center in Pittsburgh on June 26, sandwiched in between the UFC 131: Lesnar vs. Rift Gold Dos Santos and UFC 132: Cruz vs. Faber events.
Kampmann (17-5) is coming off back-to-back losses, both ending in controversial decisions. Kampmann took a split decision loss to Jake Shields at UFC 121 in October that led to Shields earning a shot against champion Georges St-Pierre.RIFT Platinum Next, Kampmann lost a unanimous decision in March to Diego Sanchez in a UFC on Versus 3 fight where Kampmann landed more significant strikes and stopped 14 of 15 takedown attempts. Fighting exclusively for the UFC since August 2006, Kampmann owns a record of 8-4 within the promotion.RIFT Platinum
Like Kampmann, Howard (14-6) is also on a two-fight skid. However,rift gold Howard's losses have been clear defeats against Jake Ellenberger (doctor stoppage) and Thiago Alves (lopsided decision). Prior to the losses, Howard was victorious in his first four UFC fights.
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