[by:www.tingvoa.com - VOA英语网]


[00:00.10]Liver cancer is the sixth most common cancer in the world,

[00:05.61]and now researchers are developing new forms of treatment.

[00:12.71]If tests show you have liver cancer, there are several ways to treat the disease.

[00:19.45]One is removing the cancerous part of the liver.

[00:24.26]The other is having doctors replace the organ through a transplant operation.

[00:32.41]Patients who get someone else's liver must take immuno-suppressant drugs the rest of their life.

[00:41.19]The drugs keep the body from rejecting the new organ.

[00:46.91]There may be serious side effects that come with taking those powerful medicines.

[00:53.81]Chemotherapy and radiation treatments are also used to treat liver and other cancers.

[01:02.06]Those treatments require the patient to take strong drugs or exposure to radiation.

[01:11.08]The drugs or radiation destroy the cancer cells.

[01:17.00]But then, the healthy cells around the tumor are damaged.

[01:22.98]Now scientists are working on an experimental, minimally invasive treatment.

[01:31.47]They say it reduces the chances of harming the patient.

[01:37.38]This treatment involves the use of natural, non-poisonous chemicals from plants.

[01:46.06]That is why the researchers call it a “green” method for fighting cancer.

[01:53.28]Kattesh Katti is a professor of radiology and physics at the University of Missouri's School of Medicine.

[02:04.24]For more than 10 years, he has studied the use of nanotechnology to fight cancer.

[02:12.10]Nanotechnology is the science of making things unimaginably small.

[02:20.67]For this study, Katti used extremely small objects to target

[02:28.04]and destroy precancerous tumor cells in the livers of mice and human cells in the laboratory.

[02:38.89]“It sounds like a fairy tale, but we are really in advanced stages

[02:43.73] in terms of tumor treatment, in terms of disease diagnostics."

[02:49.74]Kattesh Katti used very small particles of gold.

[02:55.15]The gold was covered in a protective material called gum arabic.

[03:02.90]It comes from an acacia tree.

[03:06.66]He says the particles attract precancerous and cancer cells.

[03:13.78]Those cells are far more affected by lower levels of heat than healthy cells.

[03:22.52]Once the particles travel to and connect with the cells, they are heated with a laser.

[03:31.46]That destroys the cancer cells, but the healthy ones around them live.

[03:39.69]Katti explains how the treatment would work on a human patient.

[03:46.88]“The patient will be administered with these nano particles.

[03:50.32]Within a couple of hours,

[03:52.22]the patient will be treated with lasers, and then the patient can go home.

[03:56.71]So, there is no radioactivity.

[03:58.53]There is no toxic waste.

[04:00.50]There is no toxicity, systemic toxicity, to the patient.”

[04:04.58]What that means is the patient would not have the same side effects

[04:11.08]one can have from radiation and chemotherapy.

[04:16.07]Chemotherapy drugs often are toxic.

[04:20.99]While they kill off the cancer tumors,

[04:25.11] they are also poisonous to the healthy cells and the patient can get very sick.

[04:31.71]Katti says the cost of treatment will be low because one gram of gold can be used to treat 50 patients.

[04:44.12]He says this form of treatment could be used for other types of cancer, arthritis and other diseases.

[04:54.70]The next step is testing in human subjects.

[04:59.93]If this treatment method works, it will be good news for the nearly 800,000 people

[05:08.49]who are found to have liver cancer every year.

[05:12.94]It may also help save the lives of some 700,000 people who die every year from the disease.

[05:23.84]More than 80 percent of the liver cancer cases are found in less developed countries,

[05:33.36]with the highest numbers in Asia and Africa.

[05:37.75]In the United States, liver cancer is one of the top 10 cancers that kill.

[05:45.86]I'm Anne Ball.

来自:VOA英语网 文章地址: http://www.tingvoa.com/17/01/Researchers-Testing-New-Cancer-Treatment.html