Biomedical subjects

J H Liu

Publications and source records attributed to J H Liu.

At least 163 records · Page 9Linked to original sources

PubMed1998

Dose-response curve and time-course of effect of vecuronium in male and female patients.

To determine the differences between men and women in the dose-response curve and the time-course of effect of vecuronium, we studied 60 adult patients (30 male and 30 female), ASA I, age 18-51 yr, undergoing elective plastic surgery. Anaesthesia was maintained with nitrous oxide 60% in oxygen; thiopentone and incremental doses of fentanyl were given as required. Neuromuscular function was assessed mechanomyographically using the train-of-four (TOF) stimulation at the wrist every 12 s. The percentage depression of T1 was used as the study variable. The dose-response relationship of vecuronium was determined by a cumulative dose-response technique. The dose-response curve in men was shifted in a parallel fashion to the right, indicating a decrease in the sensitivity to vecuronium-induced neuromuscular block, compared with women. The ED50, ED90 and ED95 of vecuronium were 23.9 (4.7), 45.4 (11.2) and 55.7 (14.3) micrograms kg-1 in men and 18.4 (3.7), 33.5 (7.8) and 39.8 (9.6) micrograms kg-1 in women respectively. There were statistically significant differences in these values between the two groups (P < 0.01 in each instance). After a total dose of vecuronium 80 micrograms kg-1, neuromuscular block was significantly longer in women than in men. The duration of peak effect, clinical duration, and the total duration were 18.7 (7.1), 26.6 (8.8) and 50.6 (16.0) min respectively in men and 26.0 (7.2), 37.1 (11.2) and 65.9 (20.7) min in women. They differed significantly between men and women (P < 0.005 in each case).

Adolescent↗

PubMed1998

Weekly 24-hour infusion of high-dose 5-fluorouracil and leucovorin in patients with advanced colorectal cancer: Taiwan experience.

Between January 1994 and November 1995, 41 patients with metastatic colorectal carcinoma were enrolled in this study. All these patients had recurrent disease after a prior 5-fluorouracil based adjuvant chemotherapy or failed to achieve response by prior chemotherapy that included 5-fluorouracil. 5-Fluorouracil, 2600 mg/m2, was administered concurrently with 100 mg/m2 leucovorin over 24 hours of continuous intravenous infusion. The treatment was repeated every week until progressive disease was documented. Forty-one patients received a total of 810 courses of treatment. The overall response rate was 17.1% (95% confidence interval 5.6-28.6%). In two patients who achieved complete response, the liver was the metastatic site. The median survival was 18.4 months for responders and 12.6 months for non-responders. Gastrointestinal toxicities including diarrhea, stomatitis, nausea and vomiting were the major side-effects. Sixteen incidences (39.0%) of grade 2-3 gastrointestinal toxicities were observed. One patient (2.4%) developed a grade 3 cardiac toxicity, and another one (2.4%) had a grade 2 neurotoxicity. Hematological toxicities were minimal with no evidence of severe (grade 2 or more) leukopenia or thrombocytopenia. We conclude that in patients with pretreated metastatic colorectal cancer, weekly 24-hour infusion of high-dose 5-fluorouracil and leucovorin is associated with higher efficacy and tolerable toxicity. This regimen is a good option as a second-line treatment for those whose diseases are recurrent from or refractory to prior 5-fluorouracil, and deserves a longer period of follow-up.

Adult↗

PubMed1998

Navoban (tropisetron, ICS 205-930) and dexamethasone combination in the prevention of vomiting for patients receiving preconditioning high-dose chemotherapy before marrow transplantation.

The anti-emetic efficacy of a combination of tropisetron and dexamethasone was studied in 33 patients who underwent bone marrow transplantation. Another 50 patients receiving conventional anti-emetic therapies in bone marrow transplantation served as control. On the first and second days of preconditioning chemotherapy, 51% and 36% respectively of patients in the tropisetron and dexamethasone group did not experience vomiting, compared with only 12% and 10% of control group patients (P < 0.001). The mean number of episodes of vomiting in the tropisetron and dexamethasone group was also significantly lower than in the control group (0.97+/-1.65 vs 3.50+/-2.45 and 1.30+/-1.40 vs 4.44+/-2.91 respectively, both P < 0.001). Control of vomiting in the two groups was not significantly different during days 3-6. Analysis of patients receiving busulfan and cyclophosphamide as the preconditioning regimen still showed better anti-emetic control in the tropisetron and dexamethasone group than in the control group on the first two days of treatment (total control rate 33.3% vs 6.5% and 44.4% vs 12.9% respectively, P < 0.001). Patients given tropisetron and dexamethasone combination more frequently suffered from dizziness and burning sensation of the chest. However, diarrhea and extrapyramidal symptoms were the most frequent adverse effects seen after using conventional anti-emetic combination. The combination of tropisetron and dexamethasone was thus superior to conventional anti-emetic combinations in preventing vomiting during preconditioning period of bone marrow transplantation. The adverse effects of this combination were minimal and well tolerated by patients.

Adolescent↗

PubMed1998

Phase II study of the modified regimen of etoposide, leucovorin and 5-fluorouracil for patients with advanced gastric cancer.

BACKGROUND: The efficacy of the treatment of advanced gastric cancer is not very good. The response rate to the original etoposide--leucovorin--5-fluorouracil (ELF) treatment is 53% with tolerable side effects. Whether increasing the dose intensity by prolonging the duration of infusion with 5-fluorouracil (5-FU) and leucovorin (LV) from 3 to 5 days for advanced or metastatic gastric cancer patients would enhance the efficacy but not increase side effects is still unknown. METHODS: Thirty-six advanced or metastatic gastric cancer and chemotherapy-naïve patients with measurable or evaluable diseases were scheduled to receive intravenous etoposide 100 mg/m2/day on days 2-4, LV 300 mg/m2/day intravenously and 5-FU 500 mg/m2/day intravenously on days 1-5, every 4 weeks. All patients who received at least two courses of chemotherapy were evaluated for tumor response, survival and response duration and toxicity according to the WHO criteria. RESULTS: Thirteen patients showed a response, including five with complete response (CR). The overall response rate was 36% (95% confidence interval, CI, 20-52%) in the whole group and 46% (95% CI 28-66%) in the 28 patients with measurable disease. The median progression-free interval and overall median survival time were 5 and 7 months, respectively. The most frequent toxicity was alopecia (grade I/II 56.3%). The incidence of grade III or greater myelosuppression was 5.9%. No treatment-related death occurred. CONCLUSIONS: The efficacy of the modified ELF by increasing the dosages of 5-FU and LV is not superior to the results of the original regimen, yet it is a relatively safe and tolerable combination regimen for advanced gastric cancer.

Adult↗

PubMed1998

Toxic cardiogenic shock in a patient receiving weekly 24-h infusion of high-dose 5-fluorouracil and leucovorin.

A 54-year-old man was treated with weekly 24-h infusion of high-dose 5-fluorouracil (2600 mg/m2) and leucovorin (100 mg/m2) for metastatic colon cancer. At first, he tolerated the treatment well and no significant toxicity was identified. After a total of eight courses of treatment, a stable disease was observed, but mild shortness of breath was found on occasion. The patient had no previous history of cardiac disease and the heart performance assessed by left ventricular ejection fraction before treatment was normal. Unfortunately, acute pulmonary edema with lethal cardiogenic shock occurred during the ninth course of treatment, in spite of intensive medical treatment. The chest X-ray showed extreme cardiomegaly. Repeated assessment of his heart function by echocardiogram and ventricular ejection fraction revealed a very poor cardiac performance. Toxic cardiogenic shock during weekly 24-h infusion of high-dose 5-fluorouracil and leucovorin is extremely rare. To the best of our knowledge, no case has been reported in the English literature. We report a case and the relevant literature about the incidence, clinical picture and possible pathophysiology on 5-fluorouracil-related cardioxicity is reviewed.

Acute Disease↗

PubMed1998

The influence of acute normovolemic hemodilution on the dose-response and time course of action of vecuronium.

UNLABELLED: To evaluate the influence of acute isovolemic hemodilution on the dose-response and time course of action of vecuronium, we studied 60 adult patients with and without hemodilution during surgery. The patients with hemodilution underwent major elective plastic surgery with an anticipated surgical loss of more than 600 mL. Anesthesia was induced with thiopental 4-6 mg/kg and fentanyl 2-4 microg/kg i.v. and was maintained with 60% nitrous oxide in oxygen. Further increments of thiopental 2 mg/kg or fentanyl 2 microg/kg were given as required. Acute isovolemic hemodilution in the hemodilution group was induced by drainage of venous blood and an i.v. infusion of lactated Ringer's solution and 6% dextran, during which hematocrit and hemoglobin decreased from 45.7% to 26.2% and from 148.5 g/L to 90.2 g/L, respectively. Neuromuscular function was assessed mechanomyographically with train-of-four stimulation at the wrist every 12 s, and the percent depression of T1 response was used as the study parameter. The dose-response relationships of vecuronium in the two groups were determined by using the cumulative dose-response technique. The results showed that during hemodilution, the dose-response curve of vecuronium was shifted to the left in a parallel fashion, and the potency of vecuronium was increased. There were significant differences in the 50%, 90%, and 95% effective doses between the two groups. After the i.v. administration of vecuronium 80 microg/kg, vecuronium-induced neuromuscular block was significantly longer in the patients with hemodilution than in the control patients. The duration of peak effect, clinical duration, recovery index, and total duration in the hemodilution patients were significantly different from those in the control patients. We conclude that hemodilution induces significant changes in the pharmacodynamics of vecuronium. IMPLICATIONS: We found that patients with hemodilution were 20% more sensitive to vecuronium and had a longer duration of action after the administration of the same dose than the controls. This should be taken into account when vecuronium is used as a muscle relaxant during acute hemodilution.

Adolescent↗

PubMed1998

Dose-response and time-course of the effect of rocuronium bromide during sevoflurane anaesthesia.

To evaluate the influence of sevoflurane on the dose-response relationship and on the time-course of the effect of rocuronium, 60 adult patients undergoing elective plastic surgery were randomly allocated to either the control or the sevoflurane group. Anaesthesia was maintained with 60% nitrous oxide in oxygen and thiopentone in the control group and with 60% nitrous oxide in oxygen and an end-tidal concentration of 1.75% sevoflurane in the sevoflurane group. Neuromuscular function was assessed mechanomyographically with train-of-four stimulation at the wrist every 12s and the percentage depression of the first twitch of the train-of-four was used as the study parameter. The dose-response relationship of rocuronium in the two groups was determined by the cumulative dose-response technique. The dose-response curve of rocuronium in the sevoflurane group was shifted to the left compared to the control group, indicating a potentiation of rocuronium-induced neuromuscular block. The effective doses of rocuronium required to produce 50%, 90% and 95% twitch depression in the sevoflurane group were decreased by 30.5%, 26.7% and 25.2%, respectively, compared to the control group. Following the administration of a total dose of rocuronium of 400 micrograms.kg-1, the duration of action of, and the recovery from, rocuronium were both significantly prolonged by sevoflurane. There were significant differences in the duration of peak effect, clinical duration, recovery index and the total duration of action between the control and the sevoflurane groups.

Adolescent↗

PubMed1998

Mechanisms involved in the protective effect of estradiol-17beta on lipid peroxidation and DNA damage.

Previous studies from our laboratory have shown that estrogens can protect against lipoprotein peroxidation and DNA damage. In this study, the mechanism of estradiol-17beta (E2) action was investigated by comparing E2 with selective scavengers of reactive oxygen species (ROS) in terms of inhibition of 1) human low-density lipoprotein (LDL) peroxidation (measured by the diene conjugation method) and 2) DNA damage (measured by the formation of strand breaks in supercoiled OX-174 RFI DNA). In addition, the direct effect of E2 on the generation of individual ROS was also measured. By use of ROS scavengers, it was determined that lipoprotein peroxidation was predominantly due to superoxide (39%), with some contributions from hydrogen peroxide (23%) and peroxy (38%) radicals. E2 was a more effective inhibitor of peroxidation than all the ROS scavengers combined. In DNA damage, scavengers of hydrogen peroxide, hydroxyl, and superoxide radical offered significant protection (49-65%). E2 alone offered a similar degree of protection, and no additional effect was evident when it was combined with ROS scavengers. E2 caused a significant reduction (37%) in the production of superoxide radical by bovine heart endothelial cells in culture but had no effect on the formation of either hydrogen peroxide or hydroxyl radicals. These studies show that 1) the protection offered by E2 in terms of lipid peroxidation could be due to its ability to inhibit generation of superoxide radical and prevent further chain propagation, and 2) in DNA damage protection, E2 mainly appears to inhibit chain propagation.

Animals↗

PubMed1998

Bacterial corneal ulcer: a multivariate study.

A retrospective clinicomicrobiological review of 314 patients with bacterial corneal ulcers from January 1982 to December 1992 was performed. Multivariate statistical analysis was done with multiple logistic regression using PROC LOGIST of SAS statistical software. Positive cultures were grown from 134 (42.7%) of the patients. Pseudomonas aeruginosa, staphylococci, and Acinetobacter spp. were the most frequent pathogens. Significant associations between contact lens use and P. aeruginosa (odds ratio, OR 8.16), between previous herpes simplex keratitis and Streptococcus spp. (OR 18.2) were found. Acinetobacter spp. occurred more frequently in eyes with burn and/or lagophthalmos (OR 13.1/26.2). Staphylococcus aureus was associated with trauma (OR 6.27) and age under 50 (OR 5.08-13.6). Nonpseudomonal gram-negative bacilli were associated with age over 50 (OR 3.24). Drug sensitivity tests for these isolated microorganisms showed that vancomycin and ceftazidime were the most effective agents.

Adolescent↗

PubMed1998

[A primary study on the relationship between the weight of newborn and sucking pressure]

OBJECTIVE:In this study, the main aim is to investigate the relationship between the weight of newborn and sucking pressure.the relationship between the weight of 26 cases health newborn and sucking pressure was analyzed with "oral air manometers computer analysis system".The result showed that the relationship of both corelated positively.It showed that sucking pressure is one of the indication which reflects the condition of growth and development of newborn.

Journal Article↗

PubMed1998

Physiological factors in the circadian rhythm of protein concentration in aqueous humor.

PURPOSE: The authors addressed three questions concerning the circadian rhythm of aqueous humor protein concentration in rabbits. First, is there an endogenous oscillator for this circadian rhythm? Second, does a circadian rhythm occur for individual aqueous humor protein components? Third, what is the role of ocular sympathetic nerves, which are more active in the dark phase, in this circadian rhythm? METHODS: Adult New Zealand albino rabbits were entrained to a daily 12-hour light/12-hour dark cycle. Under a constant dark environment for 24 hours, rabbits were killed at 4-hour intervals, beginning at 2 hours before the onset of the subjective light phase. Eight rabbits were used for each of the six time points. Aqueous humor and vitreous humor were collected, and their protein concentrations were determined. Major aqueous humor protein components were resolved by polyacrylamide gel electrophoresis (PAGE), stained with silver reagent, and analyzed using densitometry. Another group of eight light-dark-entrained rabbits underwent unilateral transection of the cervical sympathetic trunk. Three weeks after the operation; the circadian elevation of intraocular pressure (IOP) at 2 hours into the dark phase was determined for both eyes. Rabbits were later killed at this time point, and total protein concentrations in aqueous humor and vitreous humor were determined in both eyes. Major aqueous humor protein components in both eyes were resolved by PAGE and were compared. RESULTS: In light-dark-entrained rabbits, a circadian rhythm of protein concentration appeared in the aqueous humor under a constant dark environment. Total protein concentration in aqueous humor increased sharply in the early subjective light phase, remained relatively high during the remainder of the subjective light phase, and decreased in the subjective dark phase. Analyses of albumin and other abundant proteins in the aqueous humor showed that all of them varied similarly in a circadian pattern. In contrast, total protein concentration in the vitreous humor remained unchanged. In rabbits with unilaterally decentralized ocular sympathetic nerves, total protein concentrations in the aqueous humor and the vitreous humor in the early dark phase showed no difference between the two eyes. In addition, there was no difference in individual aqueous humor protein concentration between the two eyes. However, the nocturnal IOP elevation in the decentralized eye was less than that in the contralateral, intact eye. CONCLUSIONS: The circadian rhythm of aqueous humor protein concentration in rabbits can continue without an external signal of dark-light change, indicating the existence of an endogenous oscillator. A similar circadian rhythm occurs for various major aqueous humor protein components. The nocturnal increase in ocular sympathetic activities plays a limited role in the circadian rhythm of aqueous humor protein concentration.

Animals↗

PubMed1998

Glaucoma following congenital cataract surgery.

BACKGROUND: Glaucoma is a well known complication that arises after congenital cataract surgery. The purpose of this research was to study eyes that manifested glaucoma after congenital cataract surgery and to identify associated factors. METHODS: A retrospective review of patients who received cataract surgery before the age of five was conducted. The chi-squared test for association was used to evaluate risk factors. RESULTS: One hundred and forty eyes of 85 patients were studied. Nineteen eyes of 12 patients had glaucoma, among which 79% was open angle. Patients who underwent secondary membranectomy for visual axis occlusion had a higher risk of glaucoma, especially when secondary membranectomy was performed within one year of primary surgery. Of eight eyes with microcornea, none developed glaucoma after surgery. No significant difference in outcome was found among the surgical methods of cataract removal. CONCLUSIONS: Aggressive clearance of lens cortex during surgery is important. Secondary membranectomy for clearing the visual axis occlusion is associated with post operative glaucoma. Frequent and long-term patient follow-up is mandatory since glaucoma may manifest many years after congenital cataract surgery.

Cataract↗

PubMed1998

Object-oriented modeling and terminologies for drug contraindications.

There is no available standardized representation of contraindications that can be used in drug knowledge bases. In this paper, an object-oriented representation of contraindications is proposed that would allow computerized checking of drug prescription safety. It distinguishes four types of contraindications: pathological state, physiological state, findings of investigation procedures, and diagnostic or therapeutic procedures. The vocabulary usable for expressing the contraindications appropriate for automated prescription checking was also investigated. ICD10 (International Classification of Diseases, tenth revision), SNOMED III (Systematized Nomenclature of Medicine), ICPC (International Classification of Primary Care), and ATC (Anatomic Therapeutic and Chemical Classification) were studied as potential sources of standardized vocabulary. A system to support entering data on contraindications into a drug knowledge base, compatible with the proposed structure and using the identified vocabulary sources, is also presented.

Artificial Intelligence↗

PubMed1998

Circadian rhythm of intraocular pressure.

Although it is well known that intraocular pressure (IOP) in humans varies throughout day and night, no consistent circadian pattern has been established. In laboratory rabbits, however, a consistent circadian rhythm of IOP has been confirmed and further characterized in recent years. The current knowledge about the nocturnal IOP elevation in rabbits is reviewed and the implications for the study of human circadian IOP pattern is discussed.

Animals↗

PubMed1998

Energy charge is not decreased in lymphocytes of patients with Leber's hereditary optic neuropathy with the 11,778 mutation.

OBJECTIVES: A defect in mitochondrial energy conservation is strongly suggested to be involved in the pathogenesis of Leber's hereditary optic neuropathy (LHON). The authors therefore compared the energy charge in lymphocytes among patients with LHON, their asymptomatic maternal lineages, and normal control subjects. MATERIALS AND METHODS: Blood samples were obtained from 7 patients, 10 asymptomatic maternal relatives, and 16 normal subjects. Molecular analysis confirmed that all had the homoplasmic 11,778 point mutation in the mtDNA of their blood cells. The concentrations of adenosine triphosphate (ATP), diphosphate (ADP), and monophosphate (AMP) were determined by high-performance liquid chromatography. The energy charge was calculated as (ATP + 1/2 ADP)/(ATP + ADP + AMP). RESULTS: The mean energy charges of lymphocytes were 0.871 +/- 0.049 in patients with LHON, 0.884 +/- 0.061 in their asymptomatic maternal relatives, and 0.885 +/- 0.061 in normal controls, respectively. No statistically significant difference was found among the three groups. CONCLUSIONS: Although the study did not find the anticipated change in energy charge in peripheral blood cells, this neither confirms nor rejects the notion that a defect in the mitochondrial oxidative phosphorylation system is involved in the pathogenesis of LHON.

Adenosine Diphosphate↗

PubMed1998

A review of ocular emergencies in a Taiwanese medical center.

BACKGROUND: Ocular injury is one of the most common problems in the Emergency Department (ED), but a general survey of ocular injuries has rarely been reported in the literature. This article reviews cases of ocular injury collected in the ED of a medical center over a 12-month period. METHODS: A retrospective analysis was done on 1,314 consecutive patients who presented with eye complaints to the ED of the Veterans General Hospital-Taipei between November 1993 and October 1994. Common ocular diagnoses and their associated variables were assessed separately. RESULTS: Ocular injuries occurred in a male to female ratio of about 1.9:1 with a peak age in the third decade. Diagnoses were grouped as trauma (43.8%) and non-trauma (56.2%). Corneal abrasion was the most common trauma reported. The main circumstances of eye trauma were play (50.0%) in children (< 15 years), work (37.1%) in the age group of 16 to 59 years and domestic activity (45.8%) in patients over 60 years of age. Blunt objects and contusions (hits or falls) caused nearly 50% of all ocular injury cases. Most of the non-traumatic cases were due to acute conjunctivitis (19.1%), followed by contact lens (CL)-related disorders (11.4%). Three cases of CL-induced corneal ulcer resulted in permanent visual morbidity. There was a trend toward an increase in acute conjunctivitis in the summer, corneal ulcer in the spring and acute glaucoma in the winter. CONCLUSIONS: Young males were found to run a higher risk of ocular accidents, especially at work. Penetrating injuries with or without a retained intraocular foreign body were the leading cause of poor visual outcomes and often occurred in patients without protective eyeglasses. With the widespread use of CLs, many potentially serious complications were noted in the ED, which deserve attention.

Adolescent↗

PubMed1998

Nocturnal elevation of intraocular pressure in young adults.

PURPOSE: To distinguish 24-hour (circadian) and postural effects on intraocular pressure (IOP) in healthy young adults. METHODS: Thirty-three volunteers were housed in a sleep laboratory for 1 day under a strictly controlled 16-hour light and 8-hour dark environment. Sleep was encouraged in the dark period. Intraocular pressure was measured in each eye every 2 hours using a pneumatonometer. Researchers used night-vision goggles to perform IOP measurements in the dark, while the subject's light exposure was minimized. In the first group of 12 subjects, measurements were taken with subjects in the sitting position during the light-wake period and supine during the dark period. In the second group of 21 subjects, all IOP measurements were taken with the subjects supine. RESULTS: Average IOP was significantly higher in the dark period than in the light-wake period in both groups. The lowest IOP occurred in the last light-wake measurement, and the peak IOP occurred in the last dark measurement. The trough-peak difference in IOP was 8.2+/-1.4 mm Hg (mean +/- SEM) in the first group. Intraocular pressure changed sharply at the transitions between light and dark. In the second group, the trough-peak IOP difference was 3.8+/-0.9 mm Hg. Intraocular pressure changed gradually throughout the 24-hour period. In comparison with the sitting IOP in the first group, the supine IOP in the second group was significantly higher during the light-wake period. CONCLUSIONS: Circadian rhythms of IOP were shown in young adults, with the peaks occurring in the late dark period. A nocturnal IOP elevation can appear independent of body position change, but change of posture from upright to recumbent may contribute to the relative nocturnal IOP elevation.

Adolescent↗

PubMed1998

Twenty-four-hour change in axial length in the rabbit eye.

PURPOSE: To study the 24-hour changes in axial length, lens thickness, and anterior chamber depth in rabbits and to examine the role of ocular sympathetic activity on these changes. METHODS: Young adult rabbits were entrained to a daily 12-hour light-12-hour dark cycle. Axial length, lens thickness, and anterior chamber depth were measured using ultrasonic techniques. In the first group of 12 rabbits, measurements were taken in the middle light phase and in the early dark phase. In the second group of 12 rabbits, measurements were taken in constant dark every 2 hours for a period of 24 hours. The latter group of rabbits underwent unilateral transection of the cervical sympathetic trunk. Three to four weeks later, axial length, lens thickness, and anterior chamber depth were measured again in constant dark every 2 hours for 24 hours. RESULTS: Under the light- dark condition, axial length and anterior chamber depth were larger in the early dark phase than in the middle light phase. Lens thickness changed in the opposite direction. Under the constant-dark condition, axial length and anterior chamber depth changed gradually during the 24-hour period. The trough appeared in the late subjective light phase, and the peak appeared in the late subjective dark phase. Lens thickness remained relatively constant. In the eyes with decentralized ocular sympathetic nerves, 24-hour changes in axial length and anterior chamber depth occurred. However, magnitudes of nocturnal enlargement were relatively smaller than those in the intact eyes. Although larger in the decentralized eyes, lens thickness appeared unchanged in either eye for 24 hours. CONCLUSIONS: Consistent 24-hour changes in axial length and anterior chamber depth occur in young adult rabbits. These changes are driven endogenously. Significant portions of the nocturnal enlargements of axial length and anterior chamber depth are unrelated to ocular sympathetic activity.

Animals↗