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F-response has been found to be useful in the evaluation of peripheral nerve conduction in adults and may be especially useful in paediatric nerve conduction studies. In newborns, the nerve conduction velocity is very slow compared to adults because of immaturity of myelination. To assess the effect of age on F-response in 20 neonates, (1 to 28 days), infants (1 mo- 1 y) and children (2-12 y), motor nerve conduction velocity of median, peroneal; sensory conduction velocity of median and F-response from abductor pollicis brevis (APB) by stimulation of median nerve at the wrist were evaluated. The nerve conduction velocity in the neonates was nearly half of that in children and was significantly related to age. F-minimal latency (F-min) showed biphasic distribution; in neonates it was 17 ms, in infants 15 ms and in children 16 ms. The amplitude of F-response was higher compared to infants and children (P less than 0.001). H-reflex in ABP was elicited in all neonates and 55% of infants, its mean latency was 17.9 ms and 15.7 ms respectively. Long latency and high amplitude of F-response and presence of H-reflex in ABP in neonates and infants are due to the immaturity of the nervous system and should be kept in mind while interpreting F-responses in newborns.

A study was carried out to determine the effects of rice husk dust on pulmonary functions in Rice mill workers. The study population consisted of 150 male Rice mill workers from 6 Rice mills with 50 controls of similar age, sex, ethnic group and agricultural work background. Twenty eight Rice mill workers showed obstructive, whereas eight workers showed restrictive type of pulmonary impairment. The results show that the duration of exposure of Rice husk dust is the workers is related to the degree of decline in FVC, FEV1, FEV3, PEFR and MVV. This could be attributed to allergic inflammatory reactions of pulmonary tissue due to Rice husk dust.

Angiotensin II is produced physiologically in response to renal ischaemia due to hypotension. It's effect on heart rate and blood pressure were studied on anaesthetised mongrel dogs. Angiotensin II was given in different concentrations, by intravenous, intraarterial in carotid artery and intracerebroventricular routes. Cervical vagotomy and carotid sinus inactivation were done is abolish the reflex inhibition produced by baroreflexes. Rise of B.P. is due to mainly peripheral vasopressor action of angiotensin II, however it is shown to have a central component as well. This is demonstrated by ICV injections. Tachycardia due to central action is also demonstrated in this study. Both actions are significant. This study also confirm the earlier findings that angiotensin II passes the blood brain barrier.

The effects of angiotensin II were studied on isolated atrial preparations of nonreserpinised and reserpinised rabbits, before and after treating the preparations by propranolol. Peripheral action of angiotensin was cardioaccelerator via direct stimulation of beta-receptors of the atria in isolated atrial preparations.