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71.
Spontaneous thymoma was found in the left lobe of the thymus of a male 10-week-old Sprague-Dawley (SD) rat. Microscopically, the thymic mass showed a sheet of dark area with multiple pale foci. The dark area mainly consisted of densely compacted small lymphoid cells with sporadic large epithelioid cells and mitotic figures. The epithelioid cells and mitotic figures were more frequent than those of the normal thymic cortex in this animal. The multiple pale foci were similar to the normal thymic medulla and occasionally had Hassall's corpuscles; thus, they were regarded as medullary differentiation areas. Furthermore, some perivascular spaces recognized as characteristics of thymoma were present in the center of the mass. Immunohistochemically, the epithelioid cells in the dark area were positive for cytokeratin. Ultrastructurally, desmosomes and tonofilaments were observed in the epithelioid cells. Thus, this tumor was diagnosed as a thymoma. This is a rare case of thymoma occurring spontaneously in young adult SD rat.  相似文献   
72.
The effect of rbGM-CSF intramammary infusion on the subclinical mastitis was evaluated by the somatic cell count (SCC) and expression of adhesion molecules (CD62L and CD11b) on the surface of neutrophils (PMN) in blood and milk. Fifteen cows diagnosed to have subclinical mastitis were used in this study. Seven cows showed a decrease in the SCC (decreased group), whereas 8 cows showed an increase in the SCC (increased group) 7 days after infusion of rbGM-CSF compared to pre infusion level. The percentage of CD62+ cells tended to be lower and CD11b+cells tended to be higher at 6 h on blood PMN in the decreased group of cows. Increased group of cows showed opposite tendencies. The mean fluorescent intensity of these adhesion molecules expressed on PMN in blood and milk was similar in both groups. These results suggested some association between expression of adhesion molecules and changes in SCC by rbGM-CSF. Responsiveness of PMN adhesion molecules to rbGM-CSF might determine the changes in SCC of the subclinical mastitic cows after infusion of rbGM-CSF.  相似文献   
73.
Cattle are major hosts of Cryptosporidium spp. Cryptosporidiosis in neonatal calves is associated with retarded growth, weight loss and calf mortality, and zoonotic infections in humans. In many areas, cow-calf glazing system is an important beef cattle rearing method with distinct advantages in terms of cost and the labor required. However, few epidemiologic studies of Cryptosporidium spp. have been conducted in this system, especially using molecular diagnostic tools. To understand the transmission of Cryptosporidium spp. in a grazing system, we followed cryptosporidiosis on a grazing farm in Osaki City, Miyagi Prefecture, in northwest Japan for one year. Fecal samples were collected from Japanese Black and Japanese Shorthorn cattle and examined by PCR-RFLP and sequence analyses. Of 113 fecal samples collected in October 2010, 23 (20%) were positive for Cryptosporidium, including 15 samples (13%) having C. bovis, 6 (5%) having C. ryanae, and 2 (2%) having mixed infections of both species. Additionally, C. bovis or C. ryanae was detected on all other sampling dates involving smaller numbers of animals. The infection rate of C. bovis was significantly different among age groups, and calve-to-calve infection might be the major route of cryptosporidiosis transmission in beef cattle. Interestingly, one animal had C. bovis infection or re-infection for one year. Our results suggest that C. bovis and C. ryanae are distributed in Japan, but might have low level of detection in grazing beef cattle.  相似文献   
74.
Sugi sapwood samples were processed with aqueous solution of acetic acid in order to find the response of the weight of sugi sapwood and the treatment of aqueous solution of acetic acid. The result showed that loss of weight for the treated sugisapwood was about equal to yield of extracts from sugi sapwood, and increased with the increment of the concentration of aqueous solution of acetic acid. Fourier transform infrared spectroscopy spectra changes of the treated sugi wood and extracts from sugi sapwood were analyzed by FT-IR spectroscopic technique. Increasing tendency of absorption intensities of the stretching vibration at 3 400 cm^-1 of hydroxyl group (OH) and C=C in lignin stretching vibration at 1510 cm^-1 of benzene ring inlignin were observed from FT-IR of the treated sugi sapwood. From FT-IR spectra of extracts from sugi sapwood by aqueoussolution of acetic acid, the dissolution of lignin was observed during the treatment with 30% acetic acid solution aqueous.  相似文献   
75.
Recently, large-scale gene expression profiling is often performed using RNA extracted from unfixed frozen or formalin-fixed paraffin embedded (FFPE) samples. However, both types of samples have drawbacks in terms of the morphological preservation and RNA quality. In the present study, we investigated 30 human prostate tissues using the PFA-AMeX method (fixation using paraformaldehyde (PFA) followed by embedding in paraffin by AMeX) with a DNA microarray combined with laser-capture microdissection. Morphologically, in contrast to the case of atypical adenomatous hyperplasia, loss of basal cells in prostate adenocarcinomas was as obvious in PFA-AMeX samples as in FFPE samples. As for quality, the loss of rRNA peaks 18S and 28S on the capillary electropherograms from both FFPE and PFA-AMeX samples showed that the RNA was degraded equally during processing. However, qRT-PCR with 3’ and 5’ primer sets designed against human beta-actin revealed that, although RNA degradation occurred in both methods, it occurred more mildly in the PFA-AMeX samples. In conclusion, the PFA-AMeX method is good with respect to morphology and RNA quality, which makes it a promising tool for DNA microarrays combined with laser-capture microdissection, and if the appropriate RNA quality criteria are used, the capture of credible GeneChip data is well over 80% efficient, at least in human prostate specimens.  相似文献   
76.
In the Uranouchi Inlet, which has a commercial fishery of littleneck clam Ruditapes philippinarum, potentially toxigenic species of Dinophysis acuminata showed an annual occurrence except for the summer of 2000–2002. Relatively high abundances of D. acuminata were observed in April 2000 and November 2002. Some samples of D. acuminata cells, which were collected from the inlet in autumn 2002, contained pectenotoxin-2 (0.9–2.8 pg/cell) and okadaic acid (1.9–2.8 pg/cell). Cell length and hypotheca width of D. acuminata found in the Uranouchi Inlet were 33.7–45.0 and 21.0–31.6 μm, respectively. The length-width ratios ranged 1.21–1.71. Sequences of the 5.8S ribosomal RNA gene and flanking internal transcribed spacers, 1 and 2 of cells of D. acuminata from the inlet fell into a D. acuminata complex clade that included, D. acuminata-D. sacculus-D. acuta reported by others. In the inlet, occurrences of D. acuminata were detected within a broad water temperature range between 13.0 and 26.9°C, and those showing more than 25 cells/L were within 16.4–17.3°C for temperature and 27.6 and 34.1 for salinity. This is the first report that cells of Dinophysis acuminata from southern Japanese coastal waters contained okadaic acid and pectenotoxin-2.  相似文献   
77.
Heading date 1 (Hd1) is one of the major determinants of flowering time and regional adaptability in rice (Oryza sativa L.), because there is a significant correlation between Hd1 allelic diversity and phenotypic differences in rice cultivars. In this study, we isolated a novel rice mutant with a Tos17 retrotransposon insertion upstream of Hd1. The Tos17 insertion mutant of Hd1 [designated as Tos17(Hd1)] had decreased photoperiod sensitivity and mRNA expression of Hd1, as compared with wild‐type Nipponbare. Between Tos17(Hd1) and Nipponbare, expression levels of OsPRR1 and OsGI were similar, whereas those of two florigen genes Hd3a and RFT1, were significantly different under both short and long‐day conditions. Tos17(Hd1) showed photoperiod sensitivity intermediate between that of Nipponbare and a near‐isogenic line having a non‐functional allele of Hd1, indicating that Tos17(Hd1) has an attenuated but functional Hd1 allele. Our results revealed that allele mining of Hd1 may provide good opportunities to develop novel rice cultivars showing different levels of photoperiod sensitivity.  相似文献   
78.
We aimed to determine the effects of nutritional status on concentrations of somatotropic axis hormones (growth hormone (GH) and insulin‐like growth factor 1 (IGF‐1)), insulin and metabolites (glucose, total protein and nonesterified fatty acids (NEFA)) in the plasma and colostrum in late antepartum cows. Eight pregnant Japanese Black cows were randomly assigned to two experimental groups (n = 4 per group). Control cows (CON) received 100% of their nutritional requirements until parturition, whereas restricted group cows (RES) received 60% of their nutritional requirements. Blood samples were taken during the antepartum period, and blood and colostrum samples were collected on days 0, 1, and 3 after calving. Compared to the CON group, the RES group had higher concentrations of GH and NEFA in plasma, but significantly lower concentrations of glucose and insulin in plasma. The concentrations of GH in plasma after calving were significantly higher, but total plasma protein was significantly lower in RES than in CON cows. Compared to the CON group, the RES group had significantly higher concentrations of GH in colostrum, but significantly lower total concentrations of protein in colostrum. Concentrations of IGF‐1 were not different between the two groups. These findings suggest that maternal nutritional status during late gestation influences concentrations of GH and total protein in the blood and colostrum of Japanese Black cows.  相似文献   
79.
This study was conducted to investigate the effects of parity and litter size on gestation length in beagle bitches. The mean duration of the initial elevation (>2 ng/mL) in progesterone concentrations after the onset of proestrus was shorter (P < 0.05) in bitches without (nulliparous) whelping experience than in bitches with (multiparous) whelping experience (6.9 d versus 8.0 d). When calculated as the interval between the day of initial elevation in progesterone concentrations and the day of whelping, the gestation length in the nulliparous bitches was noted to be similar to that in the multiparous bitches (64.3 d versus 64.2 d). No significant correlation between gestation length and litter size was observed in any of the bitches. Our results indicate that the gestation length in beagle bitches is not affected by parity or litter size.  相似文献   
80.
Nasunin, delphinidin-3-(p-coumaroylrutinoside)-5-glucoside, an antioxidant anthocyanin isolated from eggplant peels, was demonstrated as an angiogenesis inhibitor. Nasunin at higher 10 microM suppressed microvessel outgrowth in an ex vivo angiogenesis assay using a rat aortic ring. The effect of nasunin was examined in various in vitro angiogenesis models using human umbilical vein endothelial cells (HUVECs). Nasunin suppressed HUVEC proliferation in a dose-dependent manner (50-200 microM); however, it had no significant effect on HUVEC chemotaxis in a Boyden chamber assay and HUVEC tube formation on a reconstituted basement membrane. These results imply that nasunin with both antioxidant and antiangiogenic activities might be useful to prevent angiogenesis-related diseases.  相似文献   
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