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1.
本文演示了四焦点开关傅里叶域光学相干断层扫描系统用于全眼段成像和体内视轴参数(VAP)测量的可行性.使用包括不同厚度平行玻璃板的两个同步转盘来将探测光束的焦点位置从角膜以及晶状体的前部和后部切换到视网膜.该过程同时增加了参考光束的深度范围.这种多级聚焦的方法可以使探测光束完全聚焦在人眼的每个部分.初步实验表明,该方法可...  相似文献   

2.
Five species of macaques and one species of mangabey comprising a total of 324 monkeys (132 males and 192 females) were given visual examinations which included measures of corneal curvature, depth of the anterior chamber, thickness of the lens, depth of the vitreous chamber, total axial length, total power of the eye and intraocular pressure as well as the refractive error of eye under cycloplegia in the anesthetized monkey. Cercocebus and Macaca mulatta demonstrated the greatest amount of myopia and Macaca fascicularis the least, with M. speciosa, M. fuscata, and M. nemestrina in order between these extremes. The M. nemestrina eye approximates that of the chimpanzee in size and relationship of the components. The findings indicate that males have larger eyes than females, the curvature of the cornea decreases as the axial length increases, and there is a close relationship between the length of the eye and the amount of myopic refractive error. There is some evidence that amount of myopia and the percentage of animals showing a myopic refractive error are related to the visual conditions and the behavior patterns of the different species.  相似文献   

3.
We studied the normal ocular development of the chick (Gallus gallus domesticus, White Leghorn) up to 15 days of age using both longitudinal and cross-sectional methods. The change in refractive error, corneal curvature and axial ocular distances were used to construct schematic eyes. Equations are presented which allow prediction of refractive error changes associated with changes in vitreous chamber depth. The mean refractive error was +3.2 D at hatching, which reduced by 66% over the first 3 days and stabilized by 11 days of age. The lens thickened and the anterior chamber deepened from hatching, but vitreal elongation and corneal flattening were delayed until after the first 3 days, suggesting that normal eye growth may be initially inhibited or inactive during an initial emmetropization period, and subsequently activated in response to myopic defocus arising from the continually expanding lens. Finally, when compared with published data on other chick strains, we find differences in the degree of hyperopia at hatching due to differences in lens thickness. However, the rate of ocular and vitreal expansion and the developmental changes in corneal power are similar, making the schematic eyes presented here generally applicable to different strains of chickens.  相似文献   

4.
The development of the chamber angle was studied in the eyes of heterozygous Pax6(lacZ/+) mutant mice (Nature 387 (1997) 406). Mutations in PAX6 cause aniridia, a condition that is frequently associated with glaucoma, a blinding disease that may be associated with chamber angle defects. Mesenchymal cells were seen in the chamber angle at P1-P5. In wild-type mice, these cells differentiated into typical trabecular meshwork (TM) cells next to Schlemm's canal. In Pax6(lacZ/+) mice, TM cells remained undifferentiated and Schlemm's canal was absent. From P1 to P4, staining for beta-galactosidase and immunoreactivity for Pax6 were observed in chamber angle mesenchyme, but were absent later. Cultured murine TM cells expressed Pax6. The defects in chamber angle and TM differentiation were associated with a wide spectrum of other anterior eye defects, which included various degrees of iris hypoplasia and corneal haze, isolated iridocorneal adhesions and atypical coloboma, and a vascularized cornea in all adult animals. A third of the animals showed Peters' anomaly including corneal opacity and iridocorneal adhesions. The separation of the lens from the cornea was incomplete, and epithelial layers of lens and cornea were continuous. Pax6 activity is directly required for differentiation of the chamber angle. Variations in phenotype of Pax6(lacZ/+) mice appear not to involve direct dominant-negative or dose-dependent effects.  相似文献   

5.
Objective of this study was to describe intraocular measurements in newly born foals (1–7 days of age) and assess the association between globe measurements and gender, laterality, and body weight. B-scan ultrasonographic biometry was performed on both eyes of 22 healthy foals (44 eyes) ages 1–7 days using a 10-MHz transducer. Intraocular measurements (anterior chamber depth, central lens thickness, vitreous chamber depth, axial globe length, longitudinal globe length, lens poles distance) were carried out using the ultrasound internal calipers. The influence of gender (male or female), laterality (right or left eye), and body weight (“light” <48 kg; “heavy” ≥48 kg) on ocular measurements was analysed by the Student t test. Values of P<0.05 were accepted as significant for all analyses. Mean anterior chamber depth was 2.2±0.5 mm (Standard Deviation); central lens thickness was 9.9±0.8 mm; vitreous chamber depth was 15.5±1.1 mm; axial globe length was 27.6±1.6 mm; longitudinal globe length was 35.8±1.2 mm, and lens poles distance was 16.4±1.0 mm. Intraocular measurements were not influenced by gender, laterality nor body weight. This study provides reference values for intraocular measurements in neonatal foals and may be useful in the diagnosis and treatment of congenital and acquired pathologies involving the globe.  相似文献   

6.
Morphogenesis of the eye of Siberian sturgeon   总被引:1,自引:0,他引:1  
The most relevant changes in Acipenser baeri eye organization were detected between hatching and 5 days post hatch. At this age, the eye had an anterior chamber, lens, iris, choroid gland, scleral cartilage, cornea and a vitreous chamber lined by the retina (with two photoreceptors: rods and single cones).  相似文献   

7.
Experimental Angiostrongylus costaricensis infection was carried out in inbred strains of mice (C57BL/6 BALB/c, DBA/2 and C3H/He). All strains became infected with this parasite. Marked differences in mortality and in worm burden were found among inbred strains of mice tested. A significant reduction was shown in worm length from mice compared to that from cotton rats.  相似文献   

8.
Scheimpflug imaging has recently been established for in vivo imaging of the anterior eye segment and quantitative determination of lens transparency in the mouse. This enables more effective investigations of cataract formation with the mouse model, including longitudinal studies. In order to enable recognition of disease-associated irregularities, we performed Scheimpflug measurements with the common laboratory inbred lines C57BL/6J, C3HeB/FeJ, FVB/NCrl, BALB/cByJ, and 129/SvJ in a period between 2 and 12 months of age. C57BL/6J mice showed lowest mean lens densities during the test period. Progressive cortical lens opacification was generally observed, with the earliest onset in C57BBL/6J, C3HeB/FeJ, and 129/SvJ, between 2 and 6 months after birth. Moreover, lenses of these inbred lines developed nuclear opacities. Calculated mean lens density significantly increased between 6 and 12 months of age in all inbred strains except 129/SvJ. Lens densities (and the corresponding standard deviations) of FVB/NCrl and 129/SvJ increased most likely because of differences in the genetic background. Albinism as confounder might be excluded since the albino Balb/cByJ mice are more similar to the C57BL/6J or C3Heb/FeJ mice. We further identified strain-specific anterior lens opacities (C57BL/6J) and cloudy corneal lesions (C57BL/6J, FVB/NCrl, and BALB/cByJ) at later stages. In conclusion, our results indicate that there are lifelong opacification processes in the mouse lens. The highest lens transparency and a dark coat color, which prevents interference from light reflections, make mice with the C57BL/6J background most suitable for cataract research by Scheimpflug imaging. We show that lens densitometry by Scheimpflug imaging in mouse eyes can resolve differences of less than 1 %, making it possible to detect differences in cataract development in different mouse strains, even if they are small.  相似文献   

9.
T Itoh  M Saitoh  H Iwai 《Jikken dobutsu》1989,38(3):269-273
Susceptibility of inbred mouse strains to Sendai virus (Mol strain) infection was studied. Although some mouse strains showed age differences in susceptibility between 3-to 4-week-old and 7-to 8-week-old mice, such age differences in susceptibility were not observed in susceptible DBA/2N and resistant BALB/cA mice. In 7-to 8-week-old mice, remarkable strain differences were observed in mortality and intensity of the lung lesions, but not in lung virus titers and serum antibody, between resistant BALB/cA and susceptible DBA/2N mice.  相似文献   

10.
PurposeTo distinguish the frequently misdiagnosed plateau iris eyes from pupillary block group and normal group, we compared the ocular biometrical parameters of them by A-scan ultrasongraphy.MethodsIn total, we retrospectively reviewed general characteristics and ocular findings including ocular biometric measurements of 71 normal, 39 plateau iris, and 83 pupillary block eyes.ResultsThe normal controls, plateau iris group and pupillary block group were significantly different in age, but not in gender. The anterior chamber depth tended to decrease and the lens thickness tended to increase from normal to plateau iris to pupillary block eyes. Compared to those of plateau iris group, the pupillary block group had significantly shallower anterior chamber depth (2.90mm vs. 2.33mm; p<0.001), thicker lens (4.77mm vs. 5.11mm; p<0.001), shorter axial length (23.16mm vs. 22.63mm; p<0.001), smaller relative lens position (2.28 vs. 2.16; p<0.001) and larger lens/axial length factor (2.06 vs. 2.26; p<0.001). However, when comparing plateau iris and normal eyes, only axial length and lens/axial length factor were significantly different (23.16 vs. 23.54; p<0.05 and 2.06 vs. 1.96; p<0.05).ConclusionsMeasured by A-scan ultrasonography, the ocular biometrics of plateau iris were significantly different from those of pupillary block eyes. However, our A-scan ultrasongraphy generally found no significant biometric differences between plateau iris and normal eyes. These findings suggest that while A-scan ultrasonography might be used as a practical tool for differentiating plateau iris and papillary block eyes, a more meticulous gonioscopy and other assessments may be necessary to distinguish plateau iris from normal eyes.  相似文献   

11.
Anterior segment dysgenesis describes a group of heterogeneous developmental disorders that affect the anterior chamber of the eye and are associated with an increased risk of glaucoma. Here, we report homozygous mutations in peroxidasin (PXDN) in two consanguineous Pakistani families with congenital cataract-microcornea with mild to moderate corneal opacity and in a consanguineous Cambodian family with developmental glaucoma and severe corneal opacification. These results highlight the diverse ocular phenotypes caused by PXDN mutations, which are likely due to differences in genetic background and environmental factors. Peroxidasin is an extracellular matrix-associated protein with peroxidase catalytic activity, and we confirmed localization of the protein to the cornea and lens epithelial layers. Our findings imply that peroxidasin is essential for normal development of the anterior chamber of the eye, where it may have a structural role in supporting cornea and lens architecture as well as an enzymatic role as an antioxidant enzyme in protecting the lens, trabecular meshwork, and cornea against oxidative damage.  相似文献   

12.
Male and female DBA/2NCrj (DBA/2) mice 3, 4, 5 and 10 weeks old were examined biochemically and pathologically and the results obtained were compared with those for CRJ:CD-1 (ICR) mice of the same age. The plasma levels of glucose, triglyceride and total cholesterol tended to be lower in DBA/2 mice than in ICR mice but the levels of non-esterified fatty acid, calcium and inorganic phosphorus were almost the same in the two strains. The mean body weight of DBA/2 mice was significantly lower than that of ICR mice at each examination, and the relative weights of the hearts of male and female DBA/2 mice were significantly greater than those of male and female ICR mice. Cardiac calcinosis, tongue calcification and corneal degeneration occurred exclusively in DBA/2 mice with incidences of 30%-100%. The incidence and severity of these lesions increased with age but no sex differences were seen. It was difficult to relate differences in biochemical features of the two strains with pathological findings obtained in the DBA/2 mice. The numbers of cells secreting adrenocorticotropic hormone in the pituitary glands were significantly greater in male and female DBA/2 mice than in ICR mice, suggesting a higher secretion of corticosteroids in the former strain.  相似文献   

13.
Congenital microphthalmia (CMIC) is a common developmental ocular disorder characterized by a small, and sometimes malformed, eye. Posterior microphthalmia (PM) and nanophthalmia are two rare subtypes of isolated CMIC characterized by extreme hyperopia due to short axial length and elevated lens/eye volume ratio. While nanophthalmia is associated with a reduced size in both anterior and posterior segments, PM involves a normal-size anterior chamber but a small posterior segment.  相似文献   

14.
Purpose of the paper was to evaluate ocular optical components (OOC) interactions in a large number of emmetropes. A cross-sectional study of 1,000 emmetropes, aged from 18-40 years, has been conducted. Complete ophthalmological examination, corneal radius (CR) measurement, keratometry and echobiometry of both eyes were performed. The highest correlation of OOC was that of axial length (Ax) with vitreal body (CV) on both eyes (r = 0.79 for the right eye (RE); r = 0.81 for the left eye (LE)). The axial length had a positive correlation with the anterior chamber depth (ACD) on both eyes as well, but the coefficient was very low (r = 0.29 for the RE; r = 0.32 for the LE). The only negative correlation Ax had on both eyes was with the lens (L) (r = -0.17 for the RE; r = -0.19 for the LE). Keratometry of the horizontal (K1) and vertical meridian (K2) showed a negative correlation with CV and Ax on both eyes (for K1 r = -0.64 for CV r = -0.54 for Ax; for K2 r = -0.67 for CV r = -0.68 for Ax). CR had a positive correlation with Ax (r = 0.74) and CV (r = 0.79). It showed a negative correlation with L (r = -0.58). CV had a high, positive correlation with Ax (r = 0.72 for the RE; r = 0.75 for the LE). The correlation with K1 and K2 was negative. Our study showed that the axial length, keratometry, corneal radius, lens thickness and vitreal body were the most important OOC that correlated with each other following a pattern in our group of emmetropes. They interacted in such a way that in the subjects with axial length above the average value, the vitreal body was longer but the lens was thinner and the cornea was of less power. This could explain at least one of the mechanisms of emmetropization.  相似文献   

15.
Two inbred strains of mice, C57BL/6J and DBA/2J, ranging in age from 2 to 38 months, were tested in an open field using the free exploration method. Scores were obtained for locomotor activity, exploratory behavior and emotionality. Strain differences were observed for all three variables. Beginning at late maturity (12 months), locomotor activity decreased with increasing age. Exploratory behavior was at a low level for DBA/2J mice at all ages. For C57BL/6J mice, exploratory behavior decreased significantly between 2 and 6 months and remained stable thereafter. Emotionality remained unchanged with advancing age for both strains of mice.  相似文献   

16.
W M Layton  M W Layton 《Teratology》1979,19(2):229-235
Cadmium (CdSO4) was given ip on day 9 at 12 or 24 mumol/kg to pregnant CD-1 (non-inbred) mice. Fetuses showed malformations of the limbs, face, trunk, and tail. There was a statistically significant relationship between the dose of cadmium and the malformation rate. Cadmium (12 mumol/kg ip on day 9) was then given to mice of six inbred strains three of which (A/J, BALB/cJ, and C57BL6J) carry a gene cdm for resistance to cadmium-induced testicular damage, and three strains (AKR/J, CBA/J, and DBA/2J) which do not. Paradoxically, the three strains resistant to cadmium induced testicular damage were significantly more sensitive to its teratogenic effects than were the other three strains. In all inbred strains most malformations involved the limbs. All forelimb defects found in inbred or non-inbred cadmium treated mice were postaxial and indistinguishable from those produced by acetazolamide in mice. The remarkable similarity of the cadmium- and acetazolamide-induced forelimb malformations may be a reflection of the limited number of ways that a rodent forelimb can react to a teratogenic insult. The hindlimb defects were all preaxial.  相似文献   

17.
K. J. Abel  K. W. Gross 《Genetics》1990,124(4):937-947
Many inbred strains of mice have a single locus encoding renin, Ren-1, whereas other inbred strains have two tandemly linked loci, Ren-1 and Ren-2. Each of these renin genes in inbred mice exhibits a unique pattern of tissue-specific expression. As a prerequisite to understanding the structural basis for the expression differences, we have physically characterized the sequence organization of this chromosomal region in both types of strains. Pulsed field gel electrophoresis was initially used to compare the long-range structure of this region in C57BL/6 (Ren-1) and DBA/2 (Ren-1 + Ren-2) mice. The structure in both inbred strains is extremely similar, except for an additional 30 kb containing Ren-2 in DBA/2 mice. The boundaries of the extra 30-kb segment were sequenced and compared to homologous sequences flanking the Ren-1 alleles. This analysis identified the precise recombination site, and also the presence of a large insertion, between the renin loci in DBA/2. The renin gene duplication apparently resulted from recombination between sequences sharing little homology, suggesting that nonhomologous chromosomal breakage and rejoining may have been involved mechanistically in the event.  相似文献   

18.
gamma-Aminobutyric acid (GABA) steady-state levels and turnover rates have been determined in 15 brain areas of 21-day- and 3-month-old DBA/2J (DBA) and C57B1/6J (C57) mice. These two inbred strains differ by their susceptibility to audiogenic seizures; moreover, the involvement of GABAergic neurotransmission has been suggested in the control of this behavior. Turnover rates are generally higher at 21 days than at 3 months of age. There are few significant differences in the GABA steady-state levels between 21-day-old seizure-prone DBA mice when compared with seizure-resistant C57 mice. In the DBA mice, the steady-state level is higher in the olfactory bulbs and lower in the posterior colliculus and the olfactory tubercles than in the C57 mice. Although there are some significant differences in GABA turnover rates and steady-state levels, intra or inter strains, it is difficult to correlate directly these differences with seizure susceptibility.  相似文献   

19.
C Gianoulakis  A Gupta 《Life sciences》1986,39(24):2315-2325
The content of beta-endorphin-like immunoreactivity (beta-EPLIR) in the anterior and neurointermediate lobe of the pituitary gland, the hypothalamus and the serum of the c57BL/6, BALB/C and DBA/2 inbred strains of mice was estimated at the resting state as well as 45 min after i.p. injection of either ethanol solution (3.0 g/kg.b.wt.) or saline. At the resting state, the neurointermediate lobe and the serum of the c57BL/6 mice showed the highest content of beta-EPLIR, while no statistically significant difference was noticed in the total beta-EPLIR content in the anterior lobe and hypothalamus. At 45 min post-ethanol treatment the beta-EPLIR content was increased in the serum of all three strains of mice studied and was decreased in the hypothalamus of the c57BL/6 mice only. Further analysis of the beta-endorphin peptides using sephadex G-75 chromatography and reverse phase high performance liquid chromatography indicated strain differences in the relative proportions of the various forms of beta-endorphin in the anterior lobe, neurointermediate lobe and the hypothalamus. These strain specific differences in the content and post-translational processing of beta-endorphin may be involved in some of the genetically determined differences in responses to ethanol by these inbred strains of mice.  相似文献   

20.
ALDH3A1 (aldehyde dehydrogenase 3A1) is abundant in the mouse cornea but undetectable in the lens, and ALDH1A1 is present at lower (catalytic) levels in the cornea and lens. To test the hypothesis that ALDH3A1 and ALDH1A1 protect the anterior segment of the eye against environmentally induced oxidative damage, Aldh1a1(-/-)/Aldh3a1(-/-) double knock-out and Aldh1a1(-/-) and Aldh3a1(-/-) single knock-out mice were evaluated for biochemical changes and cataract formation (lens opacification). The Aldh1a1/Aldh3a1- and Aldh3a1-null mice develop cataracts in the anterior and posterior subcapsular regions as well as punctate opacities in the cortex by 1 month of age. The Aldh1a1-null mice also develop cataracts later in life (6-9 months of age). One- to three-month-old Aldh-null mice exposed to UVB exhibited accelerated anterior lens subcapsular opacification, which was more pronounced in Aldh3a1(-/-) and Aldh3a1(-/-)/Aldh1a1(-/-) mice compared with Aldh1a1(-/-) and wild type animals. Cataract formation was associated with decreased proteasomal activity, increased protein oxidation, increased GSH levels, and increased levels of 4-hydroxy-2-nonenal- and malondialdehyde-protein adducts. In conclusion, these findings support the hypothesis that corneal ALDH3A1 and lens ALDH1A1 protect the eye against cataract formation via nonenzymatic (light filtering) and enzymatic (detoxification) functions.  相似文献   

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