This is what happens when I try to query as DBA:
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SQL*Plus: Release 11.2.0.1.0 Production on Mon Nov 10 22:28:00 2014

Copyright (c) 1982, 2010, Oracle.  All rights reserved.

Enter user-name: sys as sysdba  
Enter password:

Connected to:  
Oracle Database 11g Enterprise Edition Release 11.2.0.1.0 - 64bit Production
With the Partitioning, OLAP, Data Mining and Real Application Testing options

SQL> `select count(*) from dba_users;`  

> select count(*) from dba_users  
>                      *   
ERROR at line 1:   ORA-01219: database not open: queries allowed on fixed tables/views only


SQL> `alter database open;`  

> alter database open  
> *   
ERROR at line 1:   ORA-00600: internal error code, arguments: [kcratr_nab_less_than_odr], [1], [824], [95], [98], [], [], [], [],
> [], [], []

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please help to restore my db...