Aspiration vs nonaspiration technique of cytodiagnosis--a critical evaluation in 160 cases.

The two sampling techniques were studied in 160 randomly selected cases of superficial swellings in various sites of the body. They were sampled by fine needle aspiration (FNA) and by non-aspiration (NA) (a needle without application of aspiration pressure). Cell samples were cytologically assessed and critically evaluated using five objective parameters. Contamination with blood was more in lymphnode, thyroid and liver lesions in aspiration smears than NA smears and values were statistically significant. Similarly when compared for the degree of cellular trauma and cellular degeneration statistically significant better results were obtained by nonaspiration technique for lymphnode lesions. Regarding amount of cellular material obtained by FNA, statistical significant better results were found for breast lesions only. Statistically significant better maintenance of architecture was observed only for thyroid lesions by NA technique. Better average scores were observed by NA technique for lymphnode and thyroid only. Categorizing all the smears obtained by FNA & NA on the basis of their scores according to predetermined criteria, greater number of diagnostically adequate specimens were obtained by FNA than by NA but the number of diagnostically superior specimens obtained by NA technique was found to be more than that by FNA. The difference was found to be statistically significant. However the number of inadequate smears was also more by NA technique than by FNA technique.

Influence of different forms of nitrogen on uptake of ammonium, glutamate and glutamine in the cyanobacterium Nostoc muscorum.

Effect of various types of nitrogen nutrition was studied on the uptake of ammonium, glutamate and glutamine by Nostoc muscorum and its Het-Nif- mutant. Ammonium nitrogen acted as a potent inhibitor/repressor of ammonium, glutamate and glutamine transport. Nitrate nitrogen was found to be a strong inhibitor/repressor of ammonium transport, a partial inhibitor/repressor of glutamate transport but, caused a partial stimulation of glutamine transport.