The phrase "a portion of a sample" is correct and usable in written English.
It can be used when referring to a specific part or segment taken from a larger sample for analysis or examination.
Example: "In the experiment, we analyzed a portion of a sample to determine its chemical composition."
Alternatives: "a segment of a sample" or "a part of a sample."
However, tumor heterogeneity poses a significant challenge to the detection of intragenic deletions that are present in only a portion of a tumor sample.
For dyeing, a portion of a liquid sample or paper fragments were transferred to nonfluorescent microscopy glass and subjected to one-step staining according to the manufacturer's recommendation.
To generate template DNA for use in the real-time PCR, a sterile pipette tip was used to transfer a portion of a culture sample from the MAC replica plate into a single well of a 96-well PCR tray (Bio-Rad) containing 100 µL DNase-free water.
The CRM 7405-a (15 mg), a portion of all sample extracts (100 μL), and the AsHC standards (50 μL of the prepared 7.5 ± 0.2 mg As L 1 standards) were analyzed for total arsenic content in triplicate.
A portion of a powder or particle sample was placed into a small tungsten sample cuvette and weighed accurately.
StatusPeople notes that their results are inexact, as their algorithm samples a portion of a Tweeter's followers and then extrapolates relative percentages across the entire data sample.
In addition, the applications where a vision sensor can only sample a portion of a part from a single viewpoint, the sensor planning problem becomes critically important.
Furthermore, the majority of these sequences were only found in one of the five mosquito lines suggesting that our sequencing efforts had sampled only a portion of a much larger piRNA pool.
A portion of each sample was harvested and dried at 70 °C for measurement of the dry cell weight.
A portion of each sample was spun down, stored on ice for a maximum of 4 h, and stored as plasma samples at -70 °C until analysis.
