hi; my use reverse proxy and html files to be read by nginx, but I just want to have onyl html files no-cache ..

my v_hosts.conf
server {
error_log /var/log/nginx/vhost-error_log warn;
listen 46.4.103.194:80;
server_name skystar-2.com dvbking.com www.dvbking.com www.skystar-2.com;
access_log /usr/local/apache/domlogs/skystar-2.com-bytes_log bytes_log;
access_log /usr/local/apache/domlogs/skystar-2.com combined;
root /home/skystar2/public_html;
error_page 404 /404.shtml;
error_page 403 /403.shtml;
error_page 502 503 504 /50x.html;
location / {
location ~.*\.(3gp|gif|jpg|jpeg|png|ico|wmv|avi|asf|asx|mpg|mpeg|mp4|pls|mp3|mid|wav|swf|flv|txt|js|css|html|htm|exe|zip|tar|rar|gz|tgz|bz2|uha|7z|doc|docx|xls|xlsx|pdf|iso)$ {
expires 7d;
try_files $uri @backend;
}
error_page 405 = @backend;
add_header X-Cache "HIT from Backend";
proxy_pass http://46.4.103.194:8081;
include proxy.inc;
}
location @backend {
internal;
proxy_pass http://46.4.103.194:8081;
include proxy.inc;
}
location ~ .*\.(php|jsp|cgi|pl|py)?$ {
proxy_pass http://46.4.103.194:8081;
include proxy.inc;
}
location ~ /\.ht {
deny all;
}
}

my nginx.conf

user nobody;
# no need for more workers in the proxy mode
worker_processes 2;
error_log /var/log/nginx/error.log info;
worker_rlimit_nofile 20480;
events {
worker_connections 5120; # increase for busier servers
use epoll; # you should use epoll here for Linux kernels 2.6.x
}
http {
server_name_in_redirect off;
server_names_hash_max_size 10240;
server_names_hash_bucket_size 1024;
include mime.types;
default_type application/octet-stream;
server_tokens off;
sendfile on;
tcp_nopush on;
tcp_nodelay on;
keepalive_timeout 5;
gzip on;
gzip_vary on;
gzip_disable "MSIE [1-6]\.";
gzip_proxied any;
gzip_http_version 1.1;
gzip_min_length 1000;
gzip_comp_level 2;
gzip_buffers 16 8k;
# You can remove image/png image/x-icon image/gif image/jpeg if you have slowCPU
gzip_types text/plain text/html text/htm text/xml text/css application/x-javascript application/xml application/xml+rss text/javascript application/atom+xml;
ignore_invalid_headers on;
client_header_timeout 3m;
client_body_timeout 3m;
send_timeout 3m;
reset_timedout_connection on;
connection_pool_size 256;
client_header_buffer_size 256k;
large_client_header_buffers 4 256k;
client_max_body_size 200M;
client_body_buffer_size 128k;
request_pool_size 32k;
output_buffers 4 32k;
postpone_output 1460;
proxy_temp_path /tmp/nginx_proxy/;
client_body_in_file_only on;
log_format bytes_log "$msec $bytes_sent .";
include "/etc/nginx/vhosts/*";
}