求PCR引物设计
哪位朋友帮我设计一个引物,用下面的序列,最好有设计步骤,满意答案后再加30分,
tgagaaaaca actctctatt ggaatgaaga atctttataa
121 aattaacttt tcaatatcac accaaggttg ctggaccagc aaaataaaag atagtgttgt
181 taccttaaat gtatcaaaat ataataataa gaaagtcaga gtcacaatag cttctccaaa
241 attaatagta actgacctaa aaaggtcaga aaacgtttac gaaattctaa agtatagaaa
301 ggtaaaaggg ggttatataa ttgacttcct tgaagatctg agtactacaa tttcaggata
361 tatactctcg agcagtaata tattagaata tagaaatgtc gtaagggaag gaatagaaaa
421 gtgggaagta acaactttag ccaaatcttt agtaggcaaa ttatcagaaa gatttcccat
481 agatagcatt gtagttaaag aaataaagtt ttcagatatg ttctataatg gtttgacaga
541 aaaggagata ctagtcctaa aaaccgcaat aactatggga tatttcaatt atccaaggca
601 aataaaagct aaggaaattg ctgaaaaatt aggtatctcc aagcaagatt tcctttatca
661 tctgcgaaaa tcaatagaga aaataatttt ctcatcagtt atagaatag
序列的全长如下，
aaaatcttcc aattatttca gtagtgtcta tcttttaata tgaaaaattt ttgatgtttt
61 agtttgaaaa atttattaag tgagaaaaca actctctatt ggaatgaaga atctttataa
121 aattaacttt tcaatatcac accaaggttg ctggaccagc aaaataaaag atagtgttgt
181 taccttaaat gtatcaaaat ataataataa gaaagtcaga gtcacaatag cttctccaaa
241 attaatagta actgacctaa aaaggtcaga aaacgtttac gaaattctaa agtatagaaa
301 ggtaaaaggg ggttatataa ttgacttcct tgaagatctg agtactacaa tttcaggata
361 tatactctcg agcagtaata tattagaata tagaaatgtc gtaagggaag gaatagaaaa
421 gtgggaagta acaactttag ccaaatcttt agtaggcaaa ttatcagaaa gatttcccat
481 agatagcatt gtagttaaag aaataaagtt ttcagatatg ttctataatg gtttgacaga
541 aaaggagata ctagtcctaa aaaccgcaat aactatggga tatttcaatt atccaaggca
601 aataaaagct aaggaaattg ctgaaaaatt aggtatctcc aagcaagatt tcctttatca
661 tctgcgaaaa tcaatagaga aaataatttt ctcatcagtt atagaatagt aattcatgca
721 tattaaatta ctaaaaattt aagtgattaa