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81.
We used a heart rate memory apparatus to measure 2047 successive R-R intervals with an accuracy of 10 msec in adult goats. For 100 successive stationary R-R intervals out of the 2047 intervals, the R-R intervals sequence was recorded graphically and the means and standard deviations (SD) were calculated. The magnitude of the variation in the R-R intervals was represented by the SD. The usefulness of the analysis of R-R intervals as an indicator of autonomic nervous activity was determined. The diagram of 100 successive R-R intervals at rest showed a conspicuous periodic fluctuation. After the administration of atropine, atropine plus propranolol or after feeding, the R-R intervals were markedly shortened and the variations in the R-R intervals were abolished. After the administration of propranolol only, the R-R intervals were prolonged and the amplitude of the fluctuations in the R-R intervals was conspicuously increased. The respiration curve and the variation in the R-R intervals at rest fluctuated in periodic synchrony. A positive correlation between the mean and the SD of the R-R intervals was highly significant. This indicates that the variations in the R-R intervals in the adult goats are closely related to autonomic nervous activity and that the analysis of the R-R intervals is suitable for the noninvasive assessment of autonomic nervous activity.  相似文献   
82.
83.
Developing lymphoid tissues of bovine fetuses ranging from 70 to 270 days of fetal age were examined by histological and immunohistochemical procedures. In the peripheral blood, surface membrane immunoglobulin bearing cells (B-lymphocytes) and sheep red blood cell rosette forming cells (T-lymphocytes) had already appeared by 70 days of fetal age. In the lymph nodes intracytoplasmic IgM positive cells appeared at 90 days of fetal age. The cells positive for IgG appeared at 150 days of fetal age and IgA positive cells appeared at 180 days of fetal age. The spleen contained intracytoplasmic immunoglobulin positive cells at almost the same time as those in the lymph nodes. In the ileocecal region, IgM positive cells and IgG positive cells were present at 180 days of fetal age and IgA positive cells were present at 210 days of fetal age. The tonsils contained IgM positive cells and IgG positive cells at 240 days of fetal age. In the thymus, terminal deoxynucleotidyl transferase positive cells appeared at 90 days of fetal age.  相似文献   
84.
1-Octen-3-ol is a major volatile metabolite produced by mold fungi. When Arabidopsis plants were treated with 1-octen-3-ol, some defense genes that are turned on by wounding or ethylene/jasmonic acid signaling were induced. The treatment also enhanced resistance of the plant against Botrytis cinerea. When the induction of defense genes with 1-octen-3-ol was compared with that by volatile methyl jasmonate (MeJA) and methyl salicylate treatments, the induction pattern was similar to that caused by MeJA. Thus, Arabidopsis seems to recognize 1-octen-3-ol and consequently activates its defense response.  相似文献   
85.
Heat stress causes oxidative stress, which decreases plasma levels of vitamin C, an antioxidative vitamin in pigs and poultry. We investigated the plasma vitamin C concentration in lactating cows exposed to a hot environment temperature. In the first experiment, plasma vitamin C concentrations of 8 lactating cows were measured in summer and autumn. The concentration was found to be significantly lower in summer. The second experiment was performed using 4 lactating cows in a crossover design. The ambient temperature was set at 18 °C in the control treatment and at 28 °C in the heat-stressing treatment. Milk yields and feed intake tended to be lower in the stressing than control treatment. Rectal temperature and respiration rate were significantly (P < 0.05) higher in the heat-stressing treatment. The plasma vitamin C concentration was significantly (P < 0.05) lower in the heat-stressing period. These results indicate that heat stress decreases the plasma vitamin C concentration. Dietary supplementation with vitamin C may be beneficial for lactating cows in hot weather.  相似文献   
86.
Most mammals, including dogs, synthesize vitamin C in the liver. We measured the plasma concentration of vitamin C to assess the body vitamin C status in 15 dogs with a portosystemic shunt (PSS). The plasma biochemical parameters indicated liver abnormalities in all the dogs. In contrast, the plasma concentration of vitamin C ranged from 2.21 to 9.03 mg/L in the 15 dogs and was below the reference range (3.2 to 8.9 mg/L) in only 2 dogs. These findings suggest that vitamin C status is not impaired in dogs with PSS.  相似文献   
87.
At necropsy, a 7-year-old Holstein cow, clinically diagnosed via rectal palpation as having malignant abdominal neoplasia was found to have many metastatic tumors of various sizes in the abdominal and thoracic cavities and in the liver, lung, kidney, adrenal, uterus, and lymph nodes. These tumors were examined by histologic and immunohistochemical methods using anti-human myoglobin, anti-bovine myoglobin, and anti-desmin sera. Tumors were diagnosed as undifferentiated alveolar rhabdomyosarcomas. The tumors in the abdominal and thoracic cavities differed histologically from the metastases in organs. The former tumors consisted of only undifferentiated cells, most of which did not stain positively for desmin or myoglobin. The metastatic tumors contained a few rhabdomyoblastic cells that stained positively for desmin and myoglobin. Tumors tissues from the cow were transplanted and propagated through six passages in athymic nude mice. After one passage, the transplanted tumor histologically resembled those from the abdominal serosa and consisted of cells with scanty cytoplasm with an alveolar arrangement. Cells from this tumor stained positively for desmin and negatively for myoglobin. After two passages through nude mice, tumor cells were of two distinct histologic types: those cells with scanty cytoplasm and elongated cells with plentiful eosinophilic cytoplasm. Both of these cells stained positively for both desmin and myoglobin. After six passages, cross striations were detected in neoplastic cells by electron microscopy. These findings illustrate that a highly undifferentiated bovine rhabdomyosarcoma, in which most of the cells in the original tumor lacked desmin and myoglobin, became better differentiated and stained positively for desmin and myoglobin after serial transplantation in nude mice.  相似文献   
88.
The removal effects of the faucet mounted type water purifier for home use were examined against Cryptosporidium parvum oocysts. The water purifier is composed of a layer of granular activated carbon and the hollow fiber membrane filter. The cartridges were unused, 25%, 50% and 75% flow down by Arizona-dust of U. S. A. Two respective cartridges were used of the examination. The faucet and the water purifier were connected by anti-pressure tube, and 3.0 x 10(7) oocysts of Cryptosporidium parvum were injected into anti-pressure tube while water was running. Twenty liter of collected purified water was examined under the fluorescent microscope. Any oocysts in the purified water collected from all cartridges were not found. Therefore, we considered this purifier as an effective one in removing Cryptosporidium oocysts from drinking water.  相似文献   
89.
90.
We describe here the detection by fluorescence of a new photosensitizer, PAD-S31, in tumours in dogs and cats and the effect of photodynamic therapy (PDT) by using PAD-S31 for skin tumours in two dogs and one cat. PAD-S31 is a hydrophilic photosensitizer that has two peaks at absorption wavelengths 406 and 665 nm in distilled water. In a preliminary experiment in mice transplanted with SCCVII and colon 26, PAD-S31 was retained in tumour tissues rather than in other organs. The tumours resected from dogs and cats after intravenous administration of PAD-S31 at a dose of 15 mg/kg emitted strong red fluorescence under light illumination of 402 nm wavelength. Animals given PAD-S31 showed no cutaneous photosensitivity under room light illumination. Irradiation at laser light 670 nm wavelength (fluence rate 150 mW/cm2 and total light dosage 150 J/cm2) on cutaneous mast cell tumours in dogs ( n=2 ) and a cutaneous basal cell tumour in a cat induced complete remission. These results suggest PAD-S31 could be a promising photosensitizer for use in a small animal veterinary practice.  相似文献   
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