The authors reviewed the English language papers concerning chronic health effects of agricultural chemicals, focusing on the incidence of cancer in pesticide users. These papers were collected using MEDLINE between 1988 and 1998 as a referencetool. According to the standard study design, the epidemiological literature is classified into cohort studies and case-control studies. These studies suggested the association between pesticides and various types of cancer such as soft tissue sarcoma, non-Hodgkin's lymphoma, lung cancer, and breast cancer. Categories of pesticides included in these studies, varied greatly, including herbicides and insecticides.
In this paper, we discussed about such problems as the selection of control groups and the assessment of pesticide exposure levels, which may pose some problems in conducting epidemiological research on the relationship between pesticides and cancer.
A model for a method of epidemiological study of health hazards due to pesticide exposure was also presented.

Pharmacological classification, based on a so-called drug challenge test (DCT), is one method to evaluate intractable pain following experimental administration of medicines. In this scenario, the appropriate medicine is prescribed for a patient with intractable pain based on the result of the DCT. A 61-year-old man was healthy until 2003, when he sustained a brachial plexus injury caused by a gas explosion. He had experienced fulgurant pain in his left upper limb since 2006, and had undergone stellate ganglion blocks, and treatment with amitriptyline. He was admitted for further treatment in 2010 because these treatments did not alleviate his fulgurant pain. He could not move his shoulder, elbow, wrist and fingers because of severe paralysis and arthrodesis of his left shoulder joint, and complained of fulgurant pain and persistent dullness in his left upper limb. He was diagnosed to have complex regional pain syndrome (CRPS) due to the brachial plexus injury, and electromyographic examinations showed evidence of a partial regrowth after sural nerve transplantation. Gabapentin was prescribed for the patient's CRPS based on the remarkable effect of thiamilal on this fulgurant pain. The frequency of the fulgurant pain decreased following the initiation of gabapentin therapy, and the persistent dullness disappeared. DCT is recommended for patients with intractable pain such as CRPS, in addition to neurological and electromyographic examinations, in order to elucidate the details of the pain and select the appropriate medication.

Post-polio syndrome (PPS) is the term used to describe the symptoms that may develop many years after acute paralytic poliomyelitis( APP). In the case of PPS, the symptoms and signs include progressive muscle wasting and weakness, limb pain, and/or fatigue, occurring one or more decades after maximal recovery from APP. An overuse of enlarged motor units is suspected to cause the deterioration of some nerve terminals or the loss of the motor units themselves. This could in turn induce PPS symptoms such as new muscle weakness and atrophy. Electromyography (EMG) is often a strong tool to diagnose and evaluate PPS. Some studies have shown that mild to moderate intensity muscular strengthening has a positive effect in patients affected by PPS. Rehabilitation for PPS patients should utilize a multiprofessional and multidisciplinary approach. PPS patients should be advised to avoid both inactivity and overuse of the affected muscles. Finally, patient evaluation is often required to access the need of orthoses and assistive devices.