Effects of Phenobarbital on Cerebral Blood Flow in the Newborn Piglet
Bibliographic record
Abstract
To determine the neonatal cerebrovascular effect of a therapeutic dose and a high dose of phenobarbital (Pb), the effect of Pb on cerebral blood flow (CBF) and total brain oxygen consumption (CMRO2) was studied in three groups of awake newborn piglets (aged 1-3.5 days). Group I (control n = 9) received normal saline solution, group II (n = 9) received a therapeutic dose of Pb (15 mg/kg i.v.) and group III (n = 9) received a high Pb dose (45 mg/kg i.v.). Four CBF measurements per piglet using radioactive microspheres (141Ce, 85Cr, 95Nb, 46Sc), arterial blood gases, O2 content, hematocrit and plasma glucose were obtained at 0, 15, 30, 60 min after saline or Pb injections. In all groups, pH, PaO2, PaCO2, blood pressure, heart rate, temperature and plasma glucose remained unchanged except a 14% decrease (p < 0.01) in blood pressure and an increase (p < 0.05) in PaCO2, 60 min after drug injection in groups II and III. Total CBF in group II decreased by 14% (p < 0.05) 15 min after drug injection and was significantly lower (p < 0.05) than control (group I) but returned to baseline after 30 min. High Pb dose progressively lowered CBF by 11% 15 min after drug injection and produced a significant decrease by 20% (p < 0.01) 30 min after drug injection with return to baseline after 60 min. Similar effects were noted in different brain regions (cerebrum and thalamus). CMRO2 remained unchanged in the control group; however, it was decreased by 35% (< 0.01 p > 0.05) 15 min after drug injection and returned to baseline after 60 min. In group III, high Pb dose lowered CMRO2 by 31% 30 min (p = 0.02) after drug injection. Data indicate that Pb exerts a minimal but transient dose-dependent effect on CBF and CMRO2.
Fetched live from OpenAlex and de-inverted. Abstracts are not stored in this database: the inverted indexes are 8.6 GB of the frame’s 9.3 GB of text, and the host has 13 GB free.
How this classification was reachedexpand
Full frame machine prediction
Teacher imitationNot calibrated prevalence, not ground truth. Human validation pending. The Gemma side is a direct model label for every work in the frame, read from the title-only record. The Codex side is a classifier learned from the 10,348 direct Codex labels and calibrated to design-weighted sample rates; fields without enough sample support carry no Codex call. Candidate is the union of the two sides; consensus is their intersection. These outputs are machine_predicted_unvalidated and are not human labels.
Distilled classifier scores by category (both heads)
| Category | Codex | Gemma |
|---|---|---|
| Metaresearch | 0.000 | 0.000 |
| Meta-epidemiology (narrow) | 0.000 | 0.000 |
| Meta-epidemiology (broad) | 0.001 | 0.000 |
| Bibliometrics | 0.000 | 0.000 |
| Science and technology studies | 0.000 | 0.001 |
| Scholarly communication | 0.000 | 0.000 |
| Open science | 0.000 | 0.000 |
| Research integrity | 0.000 | 0.001 |
| Insufficient payload (model declined to judge) | 0.001 | 0.000 |
Machine scores (provisional)
The two teacher heads of the student model, read on this work. A score orders the frame for review; it never asserts a category, and the validation status ships verbatim with every row.
Baseline scores from an immature model (maturity gate not passed, 7 training rounds). Scores rank; they never assert a category.
score_only:v0-immature-baseline · verbatim from the scoring run: score_only means the number may rank works, and no category label ships from itClassification
machine, unvalidatedMachine predicted; a candidate call from one source (direct Gemma or distilled Codex), not a consensus.
How this classification was reached, model by model and score by score, is at the end of the page under "How this classification was reached".