大学英语四级阅读技巧与训练
The recall may hurt Symbion Inc., maker of the Jarvik-7, but it won't end the request for an artificial heart. One problem with the banned model is that the tubes connecting it to an external power source created a passage infection. Inventors are now working on new devices that would be fully placed, along with a tiny power pack, in the patient's chest. The first sample products aren't expected for another 10 or 20 years. But some people are already worrying that they'11 work- and that America's overextended healthcare programs will lose a precious $ 2.5 billion to $ 5 billion a year providing them for a relatively few dying patients. If such expenditures( 开支)cut into funding for more basic care , the net effect could actually be a decline in the nation's health.