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American researchers say they have created the first full-size human heart model using 3D printing technology.
美國研究人員稱自己用3D列印技術製作了第一個全尺寸的人類心臟模型。
The model was made with a specially developed 3D printer
該模型的製作用到了經過特殊手段研製出來的3D印表機，
that uses biomaterials to produce a structure and tissues similar to a real human heart.
該印表機使用了生物材料來製作與人類心臟類似的結構和組織。
The researchers say the model heart can be a useful tool
研究人員表示，該心臟模型是非常有用的工具，
to train medical professionals in operations related to human heart function.
可以培訓從事與人類心臟功能有關的醫務人員。
It could also be used as a basis for new research
該模型也可以作為新研究的基礎，
on ways to use 3D printing technology to produce fully operating hearts to replace in people.
探尋使用3D技術來製作全功能心臟來為人類使用。
The research was led by an engineering team at America's Carnegie Mellon University.
該研究由美國卡耐基梅隆大學某工程學團隊牽頭。
Results were recently published in a paper in ACS Biomaterials Science and Engineering.
研究結果近日發布在了《美國化學學會生物材料科學與工程》上。
The team was led by biomedical engineering professor Adam Feinberg.
該團隊由生物醫學工程學教授亞當·范伯格帶領。
The team had already developed a 3D printer that could bioprint collagen.
該團隊已研製過一臺可以生物列印膠原質的3D印表機。
Collagen is the main structural protein that is found in tissues throughout the human body.
膠原質是主要的結構蛋白質，存在於人體各個組織中。
The goal of the latest project was to use this same bioprinting technology
最近這次項目的目標是使用同一種生物列印技術
to create a realistic, full-size model of a human heart.
來製作一個全尺寸的真實人類心臟模型。
Feinberg said in a statement his team was able to create such a model
範伯格在一份聲明中表示，其團隊能夠製作出這樣一種模型——
that doctors can carefully examine to prepare for heart operations.
醫生們可以通過小心研究該模型的方式來為心臟手術做準備。
But the newly-created models also permit the doctors to "manipulate" the heart,
同時，這種新製作的模型也能讓醫生們「操控」心臟，
to experience similar reactions to working with real tissue, he added.
從而體驗與真實組織互動的類似反饋，範伯格如是寫道。
Scientists have made 3D printed models of the human heart before.
科學家之前就曾使用過3D列印的人類心臟模型。
But those models were made of harder substances – such as plastic or rubber –
但這些模型當時所使用物質的堅硬度比這次更高一些——比如塑料或橡膠——
that were not effective in copying the soft tissue material found in the human heart.
這樣的材質無法有效複製人類心臟中的柔軟組織。
The new 3D printing process was also not easy, the Carnegie Mellon team said.
新的3D列印流程也遇到了一些困難，卡耐基梅隆大學的團隊如是說道。
This is because soft materials, such as collagen, start out as a liquid.
這是因為：像膠原質這樣的柔軟材質一開始都是液態的。
When such substances are printed in air, they quickly collapse during the process.
當這些物質被列印出來並接觸到空氣的時候，就會迅速分解。
So the researchers came up with their own method to 3D print soft materials.
於是，研究人員想到了用3D技術列印較軟材質的方法。
The method uses a gelatin substance to surround the structures during the printing so they do not collapse.
這個方法是：在列印的過程中使用明膠來包裹結果，這樣就不會分解了。
The team's new model heart is made from a material called alginate,
該團隊的新心臟模型是用藻朊酸鹽製作的，
a soft, natural substance made from seaweed.
藻朊酸鹽是用海藻製成的一種天然軟性物質。
The researchers say alginate has very similar properties to tissues that make up the human heart.
研究人員表示，藻朊酸鹽的特性與組成人類心臟的組織非常相似。
For example, the researchers tested the 3D printed material with sutures,
比如，研究人員在縫合中測試了3D列印材料，
which doctors use to close up wounds during operations.
所謂縫合是指醫生在手術中用來讓傷口癒合的方法。
The team said the alginate was able to stretch to support the sutures.
該團隊表示，藻朊酸鹽可以通過伸縮的方式來支持縫合。
Once they had perfected the process,
一旦流程完善了，
the researchers made additional changes to the 3D printer to produce larger objects.
研究人員就能對3D印表機做出一些額外的改動來製作更大一些的物體。
They were able to use MRI images from a patient to model and print a full-size human heart.
他們可以用病人的MRI圖片來製作並列印全尺寸的人類心臟模型。
MRI stands for magnetic resonance imaging,
MRI指核磁共振成像，
a system for producing electronic pictures of the organs inside the body.
核磁共振成像系統可以用來製作身體內部器官的電子圖像。
Feinberg's team has also experimented with pieces of tissue designed to copy the function of individual heart elements –
範伯格團隊也用組織碎片進行的實驗，製作初衷是複製人類心臟元素的功能——
such as valves that open and close and realistic blood vessels.
比如能夠開關血管的瓣膜。
The researchers say they also successfully 3D printed a model of a heart artery
研究人員表示他們已經成功地用3D印表機列印了心臟動脈的模型，
that could be used to train doctors.
可以用來培訓醫生。
The group says the same methods could be used to create other realistic organ models as well,such as livers or kidneys.
該組織表示，相同的方法也可用於製作其他真實器官模型，比如肝臟或腎臟。
Former Carnegie Mellon student Eman Mirdamadi was another lead researcher on the project.
曾就讀於卡耐基梅隆大學的學生埃曼是該項目的另一位牽頭人。
He admitted that major hurdles still prevent the bioprinting process from producing a full-sized, functional human heart.
他坦言，目前仍有一些重大阻礙會阻止生物列印流程列印出全尺寸的人類心臟模型。
But the latest progress helps establish the foundational groundwork for such efforts, he said in a statement.
但最近的進展有助於建立起實現最終目標的基礎根基，他在一份聲明中這樣寫道。
I'm Bryan Lynn.
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