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271.
The rate of biosynthesis of ribonucleic acid (as judged by the rate of incorporation of uridine into ribonucleic acid) in infant and adullt rat brain cortex slices, incubated (aerobically in tile presenice of various substrates, is directly proportionial to the adenosine triphosphate concentration. This suggests that the adenosine triphosphate concentration is one of the factors involved in the control of ribonucleic acid biosynthesis in infant and adult rat brain. Acetoacetate or beta-hydroxybutyrate is about 70 percent as effective as glucose, with both infant and adult brain, for the promotion of ribonucleic acid biosynthesis. but they are considerably mnore effective than succinate in infant brain than in adult brain. 相似文献
272.
H. Horikirizono M. Nakaichi H. Itoh K. Itamoto Y. Nemoto H. Sunahara K. Tani 《The Journal of small animal practice》2024,65(2):144-148
A 15-year-old spayed female mongrel presented with anorexia and an abdominal mass. The mass originated from the gall bladder and was surgically resected along with divisionectomy of the central hepatic division. Paroxysmal hypertension and tachycardia were noted during manipulation of the mass. Following resection, arterial blood pressure decreased significantly. Histopathological analysis confirmed a diagnosis of neuroendocrine neoplasm. Immunohistochemical staining for synaptophysin and chromogranin A yielded diffuse and strong positive results, while gastrin was positive in only 10% of the cells. The preoperative elevated concentrations of catecholamine in the urinalysis showed a marked decrease after surgery. Based on these findings, the tumour was diagnosed as a functional paraganglioma of the gall bladder. The patient has undergone regular thoracic radiographs and ultrasound examinations and, until 431 days after surgery, has shown no signs of metastases or recurrences. Based on our literature search, we report the first case of functional paraganglioma of the gall bladder in a dog. 相似文献
273.
Transport and survival of larvae of pelagic fishes in Kuroshio system region estimated with Lagrangian drifters 总被引:1,自引:0,他引:1
ABSTRACT: Transport and survival of larvae of pelagic fishes in the Kuroshio system region were studied using Lagrangian drifter data recorded from 1990 to 2003. A large portion of the drifters from the Kuroshio area south of Japan spread around the Kuroshio Extension up to 170°E, while some moved south to the offshore area of the Kuroshio because of a recirculation gyre. The monthly mean eastward movement from areas south of Japan was approximately 800–900 km, which was smaller than previous numerical estimates. The results of a survival model assuming optimal temperatures for larvae suggest that surface waters during the observation period were too warm for larval Japanese sardine, which has an optimal temperature of 16°C, and the adult abundances did not increase during the observation period. In contrast, the spawning ground temperatures and transport conditions from an area south-west of Japan in April–June matched the requirement for the larval Japanese anchovy, which has an optimal temperature of 22°C. The combined effects of temperature variations due to seasonality and water mass mixing are suggested to play an important role in determining the environmental temperatures that occur in an area. 相似文献
274.
To overcome the lability of vitamin C (L-ascorbic acid or L-AsA), an essential nutrient of shrimp diets, the efficacy of Mg-L-ascorbyl-2-phosphate (MAP), a relatively stable derivative of L-AsA, was examined.
Groups of juvenile Penaeus japonicus were fed five different test diets containing different amounts of MAP for 100 days, to determine if MAP could be utilized by shrimp. Normal growth was observed on test groups fed diets containing 1,078, 430 and 215 mg MAP per kg, whereas mass mortality occurred in populations fed diets containing 43 and 0 mg MAP per kg. The dead shrimp found in the latter two treatments exhibited blackened lesions underneath the exoskeleton. The symptom looked similar to what was reported in previous papers as L-AsA deficiency syndrome. The feeding experiment suggests that MAP can be utilized by P.japonicus as a suitable replacement for L-AsA, and a supplement of 215 to 430 mg in 1 kg is sufficient to prevent clinical signs of vitamin C deficiency.
Repeated measurements of remaining L-AsA and MAP, made after diet processing and storage, demonstrated that MAP was significantly more stable than L-AsA and was less prone to leaching in sea water. 相似文献
Groups of juvenile Penaeus japonicus were fed five different test diets containing different amounts of MAP for 100 days, to determine if MAP could be utilized by shrimp. Normal growth was observed on test groups fed diets containing 1,078, 430 and 215 mg MAP per kg, whereas mass mortality occurred in populations fed diets containing 43 and 0 mg MAP per kg. The dead shrimp found in the latter two treatments exhibited blackened lesions underneath the exoskeleton. The symptom looked similar to what was reported in previous papers as L-AsA deficiency syndrome. The feeding experiment suggests that MAP can be utilized by P.japonicus as a suitable replacement for L-AsA, and a supplement of 215 to 430 mg in 1 kg is sufficient to prevent clinical signs of vitamin C deficiency.
Repeated measurements of remaining L-AsA and MAP, made after diet processing and storage, demonstrated that MAP was significantly more stable than L-AsA and was less prone to leaching in sea water. 相似文献
275.
The 40S ribonucleoprotein particle in Escherichia coli cells, accumulated in the presence of a low concentration of chloramphenicol, lacks at least four ribosomal structural protein components which are present in the mature 50S ribosomal subunit. The 40S ribonucleoprotein prepared by exposing the 50S ribosomal subunit to a concentrated lithium chloride solution may also be deficient in the same protein components. 相似文献
276.
277.
Hata K Futaba DN Mizuno K Namai T Yumura M Iijima S 《Science (New York, N.Y.)》2004,306(5700):1362-1364
We demonstrate the efficient chemical vapor deposition synthesis of single-walled carbon nanotubes where the activity and lifetime of the catalysts are enhanced by water. Water-stimulated enhanced catalytic activity results in massive growth of superdense and vertically aligned nanotube forests with heights up to 2.5 millimeters that can be easily separated from the catalysts, providing nanotube material with carbon purity above 99.98%. Moreover, patterned, highly organized intrinsic nanotube structures were successfully fabricated. The water-assisted synthesis method addresses many critical problems that currently plague carbon nanotube synthesis. 相似文献
278.
Nishimura J Dewa Y Jin M Saegusa Y Kawai M Kemmochi S Shimamoto K Harada T Itoh T Shima T Shibutani M Mitsumori K 《Journal of toxicologic pathology》2009,22(4):255-261
To clarify the modifying effect of N-Acetyl-L-Cysteine (NAC), which has antioxidative ability, on hepatocarcinogenesis promoted by fenofibrate (FF), a peroxisome proliferator-activated receptor (PPAR) alpha agonist , male F344/N rats were administered a single intraperitoneal injection of N-diethylnitrosamine (DEN) as an initiator followed by administration of a diet containing 3,000 ppm of FF for 16 weeks. Two-thirds partial hepatectomy was performed 1 week after the FF treatment. Additionally, NAC treatments for 14 weeks from 2 weeks after the FF treatment were performed. Although the expression level of tumor protein p53 (Tp53) mRNA decreased in the DEN+FF+NAC group as compared with that in the DEN+FF group, no significant differences between the DEN+FF and DEN+FF+NAC groups were observed in the number of hepatocellular altered foci and activities of hepatocellular proliferation. In addition, the results of an antioxidant enzyme assay and measurement of the amounts of total glutathione in the liver revealed no significant difference between the DEN+FF and DEN+FF+NAC groups; although no significant differences were observed in many genes between the DEN+FF and DEN+FF+NAC groups, only glutathione peroxidase 2 (Gpx2) mRNA increased in the DEN+FF+NAC group as compared with the DEN+FF group. The results under the present experimental conditions indicate no obvious modifying effect of NAC on liver tumor promotion by FF in rats. 相似文献
279.
The purpose of this study was to measure the dynamics of serum α1-acid glycoprotein (AGP) concentration in dogs with various
tumors, and to investigate the localization of AGP in some tissues using immunohistochemical staining. Sera were obtained
from 171 dogs bearing tumors of various types. Serum AGP concentration was measured by single radial immunodiffusion. Tumors
occurring in the liver and spleen were also investigated immunohistochemically using anti-canine AGP antibody. Mean serum
AGP levels were 749 ± 602 mg/L in dogs with carcinoma (n = 39), 1,014 ± 971 mg/L with sarcoma (n = 18), and 887 ± 935 mg/L with round cell tumors (n = 46), all significantly higher than serum AGP level in healthy dogs (n = 137, 364 ± 106 mg/L). Mean serum AGP levels were significantly higher than in healthy dogs in complex mammary gland carcinoma
(n = 5, 876 ± 721 mg/L), malignant melanoma (n = 7, 1,010 ± 821 mg/L), and hepatocellular carcinoma (n = 5, 936 ± 741 mg/L) among carcinomas, hemangiosarcoma (n = 5, 1,740 ± 1,323 mg/L) among sarcomas, and lymphoma (n = 19, 1,072 ± 965 mg/L) and histiocytic tumor (n = 6, 1,800 ± 1,387 mg/L) among round cell tumors. In an immunohistochemical investigation of AGP localization, both weak
and strong staining for anti-AGP antibody were seen in hepatic tissue in dogs with primary non-tumorous lesions originating
in the spleen (hematoma) and elevated serum AGP, but all tumor tissue in the spleen was negative. Among dogs with primary
tumor lesions of the spleen (hemangiosarcoma) and elevated serum AGP levels, both weak, moderate and strong staining for anti-AGP
antibody were seen in hepatic tissue, while strong positive staining was apparent in all tumorous tissue from the spleen.
In primary tumor lesions in the liver (hepatocellular carcinoma), both moderate and strong staining for anti-AGP antibody
were seen in normal hepatic tissue, and both weak, moderate and strong staining were seen in tumor tissues of the liver. AGP
levels thus appear to be elevated in dogs with carcinomas, sarcomas, and round cell tumors. With some of these malignant tumors,
localization of AGP in tumor tissue was seen. 相似文献
280.