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51.
Body temperatures of 11 bird species, including cuckoos, were measured in an artificial meteorological room. Ratios of change in body temperature to that in air temperature were thereby obtained for each species. Cuckoos demonstrate a remarkably high value, indicating a particularly low ability to regulate body temperature. Viewed in this light, the cuckoo's parasitic behavior is very likely an adaptation to overcome a physiological disadvantage. This in turn might be expected to reinforce delay in evolution of temperature homeostasis.  相似文献   
52.
d-Amino acid oxidase (DAO), which catalyzes oxidative deamination ofd-amino acids, is known to be highly expressed in the kidney. This study was designed to examine the localization of DAO mRNA in the mouse kidney using in situ hybridization histochemistry (ISH). For comparison, ISH for mRNA of ornithine decarboxylase (ODC), which is also highly expressed in the mouse kidney, was simultaneously performed. Adult, male mice which received 1 mg of testosterone propionate or vehicle injection, were sacrificed 14 h after injection and their kidneys were removed and processed for ISH. Hybridization signals for both mRNAs were exclusively located over the epithelial cells of the proximal tubule in the vehicle-treated animals. Signals for the DAO mRNA were observed at nearly the same hybridization intensity throughout the proximal tubule, whereas hybridization signals for the ODC mRNA were observed exclusively in the pars convoluta. Following testosterone treatment, ODC mRNA in the pars convoluta was expressed with a stronger intensity than that in the vehicle-injected animals. ODC mRNA was also expressed in the pars recta with a weaker intensity than in the pars convoluta. On the other hand, DAO mRNA expression was little affected by testosterone treatment. These results indicate that, although both genes are possibly expressed in the same cells, the expression of these genes is regulated by different mechanisms.  相似文献   
53.
Sn-protoporphyrin is a potent competitive inhibitor of heme oxygenase, can suppress neonatal and other forms of hyperbilirubinemia in laboratory animals, and represents a potential new approach to the treatment of neonatal jaundice in humans. In order to study the disposition of Sn-protoporphyrin in vivo we have developed a sensitive fluorometric method for the quantitation of this metalloporphyrin in biological samples. The method is sensitive to concentrations as low as 0.01 nmol/ml, and is specific for Sn-protoporphyrin even in the presence of other porphyrins such as protoporphyrin.  相似文献   
54.
Ethylene production in developing cocklebur (Xanthium pennsyluanicumWallr.) seeds peaked when the dry weight of the seeds beganto increase in the early period of development. The productionthen began to decrease and stopped when the dry weight increasewas completed. The upsurge of ethylene production in the earlydevelopmental period paralleled increases in ACC synthase activityand the 1-aminocyclopropane-1-carboxylic acid (ACC) contentof the seeds, both of which rapidly decreased later. Malonyl-ACC (MACC) accumulated in developing cocklebur seedsduring the early period of development, before the ACC contentand ethylene production increased. Although the ACC synthaseactivity, ACC content and ethylene production showed markeddecreases, the MACC content remained almost unchanged duringthe middle period of seed development, with a pronounced decreaseoccurring in the late period. Exogenous application of MACCdid not promote ethylene production of seeds collected at thelate developmental stage. Aminoethoxyvinylglycine, an inhibitorof ACC synthase, strongly inhibited the ethylene productionof the same lot of seeds. Therefore, the decrease in the MACCcontent in developing cocklebur seeds was not due to reuse ofMACC for ethylene production. (Received May 24, 1984; Accepted August 15, 1984)  相似文献   
55.
Carbonic anhydrase (CA) activity was detected in homogenatesfrom Anabaena variabilis ATCC 29413, M-2 and M-3, but not inthe suspension of the intact cells. Activity was higher in cellsgrown in ordinary air (low-CO2 cells) than in those grown inair enriched with 2–4% CO2 (high-CO2 cells). Fractionationby centrifugation indicated that the CA from A. variabilis ATCC29413 is soluble, whereas both soluble and insoluble forms existin A. variabilis M-2 and M-3. The addition of dithiothreitoland Mg2 $ greatly decreased the CA activity of A. variabilisATCC 29413. The specific activity of the CA from A. variabilis ATCC 29413was increased ca. 200 times by purification with ammonium sulfate,DEAE-Sephadex A-50 and Sephadex G-100. Major and minor CA peaksin Sephadex G-100 chromatography showed respective molecularweights of 48,000 and 25,000. The molecular weight of the CAdetermined by polyacrylamide disc gel electrophoresis was 42,000?5,000.The activity of CA was inhibited by ethoxyzolamide (I50=2.8?10-9M), acetazolamide (I50=2.5?10-7 M) and sulfanilamide (I50=2.9?10-6M). (Received January 5, 1984; Accepted April 26, 1984)  相似文献   
56.
Summary The usefulness of LMS in postoperative immunochemotherapy of gastric cancer was investigated. In compliance with the protocol, MMC was given at a dose of 20 mg on the day of gastrectomy, and an additional 10 mg on the next day IV. The patients receiving 600 mg Tegafur daily were then divided into two groups according to whether LMS was also given or not. LMS was administered for 3 days before the operation in a daily dose of 150 mg and for 1 year or more after operation according to a schedule of 3 days' administration followed by an 11-day interval. The 2-year follow-up demonstrated that in stage III patients, the LMS (+) regimen was superior to the LMS (–) regimen, since the former prolonged the relapse-free interval significantly. The survival rate for stage III disease was also significantly higher in the LMS (+) than in the LMS (–) group. There was no significant difference in the incidence of subjective or objective side-effects between two groups. The incidence of agranulocytosis was comparable in the two groups.Gastrointestinal Cancer Research Group, Japan Levamisole Research AssociationChairmen of the Gastrointestinal Cancer Research Group, Japan LMS Research AssociationController of the Gastrointestinal Cancer Research Group, Japan LMS Research AssociationMembers of the Data Collection and Analysis SubcommitteeThis study was carried out by the Gastrointestinal Cancer Research Group, Japan LMS Research Association (directed by Prof. Kiyoshi Inokuchi, Dept. of Surgery, Kyushu University and Prof. Eiro Tsubura, Dept. of Internal Medicine, Tokushima University). The results were presented in part at the 19th General Meeting of the Japanese Society for Gastroenterological Surgery in February, 1982  相似文献   
57.
Summary A specific enzyme immunoassay of uroporphyrinogen decarboxylase was developed and applied to the detection of the human enzyme in man-rodent somatic cell hybrids. This method allowed to assign the gene for uroporphyrinogen decarboxylase to human chromosome 1.  相似文献   
58.
Summary The caudal spinal cord of Eigenmannia virescens is not enclosed in a neural canal of the vertebral column. In fact, a segmented vertebral column with neural and ventral arches is lacking and replaced by a non-segmented baton-like bony structure on which the free spinal cord is located. The baton consists of calcified bone tissue with bone cells. Individual differences exist as far as the length of the rod is concerned. The electromotor neurons of this caudal part of the spinal cord are histochemically acetylcholinesterase-positive. The electrocytes which surround this part of the spinal cord show strong enzymatic actitivity on the posterior innervated face. However, there is also activity on the non-innervated lateral and anterior faces.  相似文献   
59.
60.
Analysis of products formed in Chlorella vulgaris 11 h cellsduring photosynthesis in air containing 3,000 ppm 14CO2 at varioustemperatures revealed that the level of 14C-starch was maximumaround 20–24?C and decreased with further rise in temperatureuntil 40?C, while 14C-sucrose greatly increased at temperaturesabove about 28?C. Elevating the temperature from 20 to 38?Cduring photosynthetic 14CO2 fixation resulted in a remarkabledecrease in 14C in starch and a concomitant increase in 14Cin sucrose. This conversion of starch to sucrose when shiftingthe temperature from 20 to 38?C proceeded even in the dark.Hydrolysis of sucrose by rß-fructosidase showed that,irrespective of the experimental conditions, the radioactivitiesin sucrose were equally distributed between glucose and fructose.The enhancement of starch degradation with temperature risewas more remarkable than that of the activity of ribulose bisphosphatecarboxylase from the same cells. When Chlorella cells whichhad been preloaded with 14C-starch after photosynthesis for30 min at 20?C were incubated in the dark for an additional30 min at 20?C, 14C-starch was degraded by only about 4%. However,the values after 30-min dark incubation at 28, 32, 36 and 40?Cwere increased by about 10, 19, 36 and 50%, respectively. Duringthe temperature-dependent conversion of starch to sucrose, nosignificant amount of radioactivity accumulated in free glucoseand maltose. (Received October 27, 1981; Accepted January 9, 1982)  相似文献   
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