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91.
This report describes a spontaneous hybrid cyst in a Sprague-Dawley (SD) rat. A 52-week-old, male SD rat had a cutaneous cyst on the left mystacial pad. Histologically, the cyst wall showed infundibular differentiation with keratohyalin granules in the granular layer and matrical differentiation comprising basaloid epithelial cells with trichohyalin granules. The cyst cavity was filled with lamellar, flaky keratin and aggregates of shadow cells. Immunohistochemically, the infundibular-type epithelium was positive for cytokeratin (CK) AE1/AE3, CK KL1 and CK14 but negative for CK15, whereas the matrical-type epithelium was negative for all four CK isoforms examined. These immunohistochemical properties of the infundibular- and matrical-type epithelia were similar to those of the infundibulum and inferior segment of normal hair follicles, respectively. Based on these findings, the cyst was diagnosed as a hybrid cyst, comprising more than one type of cyst arising from various parts of the pilosebaceous unit.  相似文献   
92.
The purpose of this study was to evaluate the dark adaptation time in canine electroretinography (ERG) using a contact lens electrode with a built-in LED. Twelve eyes of six normal laboratory beagle dogs were used and exposed to steady room light at 500 lux for 30 min for light adaption. ERG was recorded at different time points during dark adaptation in sedated and light-adapted beagles. The stimulus intensity was 0.0096 cd/m2/sec. The b-wave amplitude increased significantly until 25 min of dark adaptation, whereas no significant changes in amplitudes were observed after 30 min. Dark adaptation for more than 25 min would be necessary for accurate ERG in canine ERG using a contact lens electrode with a built-in LED.  相似文献   
93.
We investigated the associations of hind limb claw lesions with claw measures and reproductive performance of sows on a commercial breeding farm. We used a five‐point scale (score of 0–4) for each hind limb claw region to generate a claw lesion score (CLS). Of 110 sows, 1.8% had no hind claw lesions, and the remaining 98.2% had at least one. The proportions of sows with a CLS of 2 and 3 were 49.1% and 3.6%, respectively. The junction region had the highest frequency of a CLS of ≥ 2 (P < 0.05). The mean toe length was 45.0 ± 0.4 to 46.4 ± 0.4 mm. Sows with the highest CLS of ≥ 2 in the lateral claw had longer sole dimensions than did sows with the highest CLS of ≤ 1 (P < 0.05). There were no significant differences in claw width or height between sows with the highest CLS of ≥ 2 and ≤ 1. There was also no difference in reproductive performance between sows with the highest CLS of ≥ 2 and ≤ 1. In conclusion, most sows had hind claw lesions. The association between CLS and claw measures indicates that the sole length can be used as an indicator of claw lesions.  相似文献   
94.
95.
Genetic Resources and Crop Evolution - Garden beet is the ancestor of fodder beets and sugar beets, but the origin of garden beet’s genetic potential to evolve novel beet types is debatable....  相似文献   
96.
Oxidation of low-density lipoprotein (LDL) has been implicated in atherogenesis. Antioxidants that prevent LDL from oxidizing may reduce atherosclerosis. This study investigated LDL antioxidant activity in edible plant products for development of dietary supplementation to prevent atherosclerosis. Fifty-two kinds of edible plants were extracted using 70% aqueous ethanol solution, and the antioxidant activity of the extracts, which inhibit human LDL oxidation induced by copper ion, was determined on the basis of the oxidation lag time and represented as epigallocatechin 3-gallate equivalent. 1,1-Diphenyl-2-picrylhydrazyl (DPPH) radical scavenging activity and total phenolic content were also measured for comparisons with antioxidant activity in LDL. Plant products showing the greatest activity in LDL oxidation assay were akamegashiwa (Mallotus japonicus) leaf, Japanese privet (Ligustrum japonicum) leaf, green tea [Camellia sinensis (L.) O. Kuntze], and astringent persimmon (Diospyros kaki). The present study revealed high levels of LDL antioxidant activity in plant products for which such activity levels are underestimated in the DPPH radical scavenging assay and Folin-Ciocalteu assay.  相似文献   
97.
Chromosomes and cytoplasms were analyzed in two lines of a somatic hybrid between onion (Allium cepa L.) and garlic (A. sativum L.). One line of the somatic hybrid had 40 chromosomes and the other 41chromosomes. Genomic in situhybridization successfully revealed the chromosome constitution of the two lines. One line had 20 chromosomes from onion and17 chromosomes from garlic, and the other had 21 chromosomes from onion and 17chromosomes from garlic. Interestingly, both lines had three chimeric chromosomes. PCR-RFLP analyses of chloroplast and mitochondrial DNAs of both lines showed that these were identical to the onion parent. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   
98.
The induction of haploid plants from F1 hybrids between CMS shallot with Allium galanthum cytoplasm and common onion was examined. Starting with 535 unpollinated flowers cultured in B5 medium 25 seedlings from part henogenetic embryos were obtained of which 13 seedlings survived. Eleven seedlings were determined as haploid plants (2n = x = 8) and 2 seedlings were doubled haploid plants (2n = 2x = 16). All haploid and doubled haploid plants preserved chloroplast DNA (cpDNA) and mitochondrial DNA (mtDNA) from A. galanthum. Segregation in different characters was observed among the haploid plants. The haploid and doubled haploid plants exhibited the different combinations of genes from shallot and common onion. Crossing of the doubled haploid plants with other shallot strains, common onion cultivars or related species may produce excellent F1 hybrids for bulb production. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   
99.
Penetration rates of laser pulses transmitted from a small-footprint airborne light detection and ranging (LiDAR) system in closed-canopy, middle-aged (40–50 years old) hinoki cypress (Chamaecyparis obtusa Sieb. et Zucc.) and sugi (Cryptomeria japonica D. Don) plantations that had similar levels of canopy openness were studied. The number of transmitted pulses was 107 427 points/ha for the hinoki cypress stand and 122 883 points/ha for the sugi stand. The penetration rates of the first (Pf) and second pulses (Ps) that reached the ground were 0.1% and 1.0% in the hinoki cypress stand, and 2.6% and 5.5% in the sugi stand, respectively. Penetration rates for the total number of pulses (Pf+s) that reached the ground within each stand were 1.1% and 8.1%, respectively, and values for Pf+s, Pf, and Ps for sugi and hinoki cypress stands were significantly different (P < 0.001). The results of this study indicated that the generation of accurate digital terrain models in dense hinoki cypress stands with complex topographies using only the data from laser pulses with poor laser penetration rates is likely to be difficult.  相似文献   
100.
This review describes the study of freeze-dried mouse sperm for practical application in preserving and transporting genetic resources. Freeze-dried sperm can be used to preserve and transport genetic resources; however, there still remain many areas which need to be studied. In particular, it is essential to assure long-term preservation over several decades or centuries. Recently, the theory of accelerated degradation kinetics to freeze-dried mouse sperm has been applied, and found that long-term preservation by conventional methods requires temperatures lower than -80 C. When the relationship between the pressure at primary drying and the preservation potential of freeze-dried mouse sperm was examined, a pressure of 0.37 mbar at primary drying significantly improved the developmental rate to the blastocyst stage. In addition, it has been shown that freeze-dried sperm stored at -80 C with and without transportation can retain their ability to generate viable offspring after storage for up to 2 years. Sperm chromatin structure assay (SCSA) was applied to mouse sperm freeze-dried under several conditions and compared the results with the embryonic developmental rates of freeze-dried sperm after intracytoplasmic sperm injection (ICSI) and with comet assay results. Furthermore, SCSA might be useful for estimation of developmental potential of fertilized eggs derived from ICSI using freeze-dried sperm in mice.  相似文献   
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