Sentence examples for samples was negative from inspiring English sources

Ziehl-Neelsen staining performed on the T1DM, T2DM and control samples was negative for the presence of any acid fast cells.

Only one of 29 HSMI samples was negative; this sample originated from a salmon net harboring fish in the early phase of HSMI, prior to the onset of fish mortality (Figure 3).

Staining of respective mouse and rat kidney samples was negative.

DNA extracted from blood and swab samples was negative for all tested pathogens.

However, ELISA of stool samples was negative for C. difficile toxin.

Reverse transcriptase polymerase chain reaction (RT-PCR) of nasopharyngeal aspirate samples was negative for coronavirus twice.

"[Results] of the three of the samples were negative.

In the 8 completed tests, 4 samples were negative for contaminants and 4, positive.

Air samples were negative, but two tests of debris on the ground were positive for traces, said officials, who minimized the health threat.

"Even if all the samples are negative, maybe you just missed it," Dr. Tauxe said.

All control samples were negative.