Analytics  Vidhya Blood Cell Detection articles, three parts 

A Step-by-Step Introduction to the Basic Object Detection Algorithms (Part 1)

https://www.analyticsvidhya.com/blog/2018/10/a-step-by-step-introduction-to-the-basic-object-detection-algorithms-part-1/#:~:text=In%20Fast%20RCNN%2C%20we%20feed,into%20a%20fully%20connected%20network.

A Practical Implementation of the Faster R-CNN Algorithm for Object Detection (Part 2 – with Python codes)

https://www.analyticsvidhya.com/blog/2018/11/implementation-faster-r-cnn-python-object-detection/?utm_source=blog&utm_medium=a-step-by-step-introduction-to-the-basic-object-detection-algorithms-part-1

A Practical Guide to Object Detection using the Popular YOLO Framework – Part III (with Python codes)

https://www.analyticsvidhya.com/blog/2018/12/practical-guide-object-detection-yolo-framewor-python/