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341.
Toshiyuki Tanaka Yusuke Wada Shunsuke Noguchi Hidetaka Nishida Hideo Akiyoshi 《Veterinary radiology & ultrasound》2023,64(2):262-270
Pyloric outflow obstructions can be caused by several types of lesions. When a thickened gastric wall and pyloric mass are detected, malignant neoplasia must be differentiated from chronic hypertrophic pyloric gastropathy. CT can characterize gastric tumors. However, based on the authors’ review of the literature, there is limited information about the CT findings of pyloric lesions. The purpose of this retrospective case series study was to assess the CT findings of canine pyloric lesions. The following CT parameters were recorded: anatomical area, involved area, lesion shape, growth patterns of wall thickening lesions, enhancement pattern of the lesion in the early and delayed phases, lymphomegaly, and pulmonary metastasis. Seventeen dogs were included in this study and had the following final diagnoses: hyperplasia (five dogs), adenoma (five dogs), adenocarcinoma (three dogs), gastrointestinal stromal tumor (GIST; two dogs), polyposis (one dog), and pyogenic granuloma (one dog). Hyperplasia, adenoma, and polyposis formed mass lesions that involved the mucosal layer. Lymphomegaly was detected in two Jack Russell terriers with hyperplasia; however, the causes were unknown because we did not perform biopsies. All adenocarcinomas formed wall-thickened lesion that involved the outer layer, with lymphomegaly. All GISTs formed mass lesion that involved the outer layer. The pyogenic granulomas formed symmetric wall-thickened lesion that involved the mucosal and outer layers. CT facilitated the characterization of canine pyloric lesions using contrast enhancement, based on the involved area and lesion shape. However, polyposis may require caution in diagnosis based on CT findings alone. 相似文献
342.
A goal in visual neuroscience is to reveal how the visual system reconstructs the three-dimensional (3D) representation of the world from two-dimensional retinal images. Although the importance of texture gradient cues in the process of 3D vision has been pointed out, most studies concentrate on the neural process based on binocular disparity. We report the neural correlates of depth perception from texture gradient in the cortex. In the caudal part of the lateral bank of intraparietal sulcus, many neurons were selective to 3D surface orientation defined by texture gradient, and their response was invariant over different types of texture pattern. Most of these neurons were also sensitive to a disparity gradient, suggesting that they integrate texture and disparity gradient signals to construct a generalized representation of 3D surface orientation. 相似文献
343.
Hiroki Yamazaki Hiroshi Sasai Miyuu Tanaka Toshiyuki Tanaka Hidetaka Nishida Shunsuke Noguchi Mitsuru Kuwamura Hideo Akiyoshi 《Veterinary and comparative oncology》2021,19(1):123-131
This study aimed to determine a reliable therapeutic biomarker for localized small intestinal lymphoma (SIL) in dogs based on clinical and histopathological features. We retrospectively investigated 84 dogs with localized SIL, including 36 dogs receiving surgery and 48 dogs receiving chemotherapy. The dogs receiving surgery were divided into two subgroups: 18 dogs (group 1) with overall survival (OS) <120 days (median OS) and 18 dogs (group 2) with OS ≥120 days. Correspondingly, the dogs receiving chemotherapy were divided into 24 dogs (group 3) with OS <98 days (median OS) and 24 dogs (group 4) with OS ≥98 days. Clinical, haematological, histopathological and immunohistochemical analyses were comparatively evaluated among the four subgroups. There was no significant difference in OS between the surgery and chemotherapy groups. In dogs receiving surgery, the rate of Ki67‐positive cells was significantly increased in group 1 compared to group 2 and showed no significant difference between groups 3 and 4. In dogs receiving chemotherapy, the rate of O6‐methylguanine‐DNA methyltransferase (MGMT) was significantly higher in group 3 than in group 4 and showed no significant difference between groups 1 and 2. Additionally, our data showed that OS in dogs with higher Ki67 expression might be significantly increased by chemotherapy than by surgery, that of those with higher MGMT expression might be significantly increased by surgery than by chemotherapy, and Ki67 and MGMT were independent of each other. Indices of Ki67 and MGMT are suggested therapeutic biomarkers to determine the optimal first‐line treatment for localized SIL in dogs. 相似文献
344.
ABSTRACT: Growth and ontogenetic migration of greeneye Chlorophthalmus albatrossis were studied in the area from 100–400 m depths in Tosa Bay, from April 1996 to March 1997, using samples collected by an otter trawl net with a 1.3 mm mesh cod end. In the monthly changes of the standard length (SL) composition, four year classes were recognized, although the third- and fourth-year classes were not clearly separated in all the monthly samples. Individuals of 40–50 mm SL settled on the bottom of the 150–200 m depth zone from August to February. By May and June, they grew to 75–80 mm SL modal size, and migrated to 200–300 m depth. In one year after settlement, they grew to 125–130 mm SL, and migrated to 300–350 m depth. They grew to a maximum of 160 mm SL and were not sampled in the winter three years after settlement, suggesting either migration or mortality. Seasonal changes in the gonadosomatic index for combined samples of males and females showed that greeneye did not mature in Tosa Bay. It is suggested that the planktonic larvae are transported from the spawning grounds, the location of which remains unknown. 相似文献
345.
ABSTRACT: In order to investigate the relationships between levels of lipid peroxides (LPO), hydroxy lipids (L-OH) and of antioxidative enzymes in live fish, cultured cells from tilapia liver (Hepa-T1) were treated with oxidative stressors, 2,2'-azobios(2-amidino-propane) dihydrochloride (AAPH) and H2 O2 . By treating with 5 mM AAPH, LPO and L-OH of the cells significantly increased time-dependently. In particular, L-OH increased from 7.6 ± 0.7 to 23.6 ± 1.8 nmol/mg protein after 2 h of treatment, and synchronously the glutathione peroxidase (GPx) activity of the cells increased from 259 ± 106 to 1970 ± 135 mU/mg protein. In the case of H2 O2 , however, no elevation of L-OH was observed. In this case, catalase (CAT) and superoxide dismutase (SOD) activities increased time-dependently. Especially, after 2 h exposure, the CAT activity increased remarkably from 217 ± 21 to 2510 ± 120 mU/mg protein, though the GPx activity did not change significantly. These results suggest that the elevation of the L-OH level is closely associated with the elevation of GPx activity, but not with that of CAT or SOD. However, when vitamin E-enriched Hepa-T1 cells were treated with AAPH and H2 O2 , the production of LPO and L-OH was suppressed significantly. The findings suggest that vitamin E also plays an important role in the levels of the oxidation products in vivo . 相似文献
346.
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348.
Toshiaki SUMIYOSHI Tomomi TANAKA Hideo KAMOMAE 《The Journal of reproduction and development》2014,60(2):106-114
Lactating Holstein-Friesian cows kept in tie-stall barn were used as subjects in this
study. Rectal examination, ultrasonography and blood sampling were conducted every other
day and then daily after the day on which diameter of the corpus luteum decreased. After
the luteal diameter decreased for 2 consecutive days, rectal and ultrasound examinations,
blood sampling, and observation of estrous signs were conducted at 6-h intervals. Most of
the estrous signs became obvious with the increase in estradiol-17β (E2) and
became most remarkable 24 to 30 hours before ovulation, at which point the E2
peak and luteinizing hormone (LH) surge were achieved, and then weakened which progression
to ovulation. The correlation between the intensity of four estrous signs (hyperemia and
swelling of the intravaginal part of the uterus, opening of the external uterine orifice
and viscosity of the cervical mucus) and the plasma E2 concentration was higher
than that of three estrous signs (swelling of the vulva, contraction of the uterus,
diameter of uterine horn) and the plasma E2 concentration. The relaxation of
the intravaginal part of the uterus showed a unique change compared with the other estrous
signs, and it became most obvious 6, 12 and 18 h before ovulation; this obviously relaxed
period was consistent with the generally accepted theoretical optimal time for artificial
insemination (AI), i.e., 6 to 24 h after initiation of estrus. These results suggest that
observation of estrous signs by vaginoscopic examination gave useful information for
detection of the optimal timing of AI in the periovulatory period in lactating dairy cows
kept in a tie-stall barn. 相似文献
349.
350.
Wen-Hsin Chung Saligrama Adavigowda Deepak Hideo Ishii 《Journal of General Plant Pathology》2013,79(2):128-135
Strobilurins, broad-spectrum fungicides used to control various diseases, may also inhibit the growth of nontarget fungi in the natural environment. Acibenzolar-S-methyl (ASM) is a plant activator; however, the effect of ASM on the growth of microflora on the leaf surface is not clear yet. ASM, strobilurins and other fungicides were sprayed on Japanese pear and cucumber plants in the field. Variations in the morphological characteristics and rDNA-ITS nucleotide sequence of isolated phylloplane fungi were evaluated. The isolation frequency of Alternaria spp., Aureobasidium spp., Cladosporium spp. and Myrothecium spp. on Japanese pear leaves treated with kresoxim-methyl and polycarbamate was lower than on nontreated pear leaves. Moreover, the frequency of Alternaria spp., Cladosporium spp., Epicoccum spp. and Fusarium spp. on leaves of two cucumber cultivars treated with azoxystrobin, triflumizole and mancozeb was lower than the frequency of fungal isolation on nontreated cucumber leaves. The effect of ASM on fungal isolation frequency was not significantly different from that on nontreated pear or cucumber leaves. The fungal genera observed and isolation frequency on the leaves treated with polycarbamate, azoxystrobin, triflumizole and mancozeb tended to be reduced compared to the no-spray treatment. 相似文献