even the requirement that biomaterials processed from these materials be nontoxic to host tissue can be met by techniques derived from studying the reactions of tissue cultures to biomaterials or from short-term implants.(5)

即使是这样的要求，即从这些材料中加工出来的生物材料应该对受移植者的组织无害，也能够通过从研究组织培养对生物材料的反应而来的，或从研究短期移植而来的技术来满足。

难句类型：

复杂修饰、省略、专有名词、固定搭配

解释：

主语the requirement后面带着一个长长的修饰主语的同位语;由于requirement的同位语中要求使用虚拟语气，所以其中的系动词成了原型(should be省略了should)。如此之长的修饰成分过后，谓语can be met与主语的关系已经很难理清了。

从by开始的状语结构更为复杂;修饰techniques的后置的定语derived from studying the reactions of tissure cultures to biomaterials or derived from studying short-term implants实际上是由or所连接的两个固定搭配the reactions of tissure cultures to biomaterials;

第二个derive from中还套了另外一个固定搭配the reactions of tissure cultures to biomaterials;

第二个derive from则干脆把derive给省略了。此外，本句的专有名词奇多，这使得阅读的难度非常高。

意群训练：

even the requirement that biomaterials processed from these materials be nontoxic to host tissue can be met by techniques derived from studying the reactions of tissue cultures to biomaterials or from short-term implants.