get Collection oder by and limit In Magento

hear  mydesign: is custom module
$limit=10
 $start=0
$modelColl=Mage::getModel('mydesign/mydesign')->getCollection()->addFieldToFilter('user_id',$userId);
            $modelColl->setOrder('mydesign_id','DESC');
            $modelColl->getSelect()->limit($limit,$start);

orders product by oder_id in magento

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get orderproduct By oder_id in magento
============================

$order = Mage::getModel('sales/order')->loadByIncrementId($order_id);
        $items = $order->getAllItems();
                        $itemcount=count($items);
                                             
                        $date=date ("Y-m-d H:i:s");
                        foreach ($items as $itemId => $item)
                        {
                       
                            $product=Mage::getModel('catalog/product')->load($item->getProductId());
                      }