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排序方式: 共有1511条查询结果,搜索用时 15 毫秒
891.
Establishment of four functional, clonal strains of animal cells in culture   总被引:14,自引:0,他引:14  
The single-cell plating technique was used to develop four clonal cell lines that perform organ-specific functions after being serially cultured for prolonged periods. These strains include steroid-secreting Leydig cells, melanomacells that form pigment, and two strains from a hormone-secreting rat pituitary tumor. One of the cell lines from the pituitary tumor secretes growt hormone, while another line derived from the same tumor secretes a substance similar to adrenocorticotropic hormone.  相似文献   
892.
Fisheries Science - To elucidate spatial and seasonal variations of radiocesium (134Cs and 137Cs) concentrations in ayu Plecoglossus altivelis, amphidromous fish samples were collected both from...  相似文献   
893.
Thuy  Linh Vu  Yamamoto  Shigeru  Kawaura  Rika  Takemura  Naoki  Yamaki  Kohei  Yasumoto  Ko  Takada  Kentaro  Watabe  Shugo  Sato  Shigeru 《Fisheries Science》2020,86(6):1101-1110
Fisheries Science - Pufferfish belonging to Lagocephalus are composed of several species, some of which have been recognized to be non-toxic. Although fish belonging to this genus inhabit a wide...  相似文献   
894.
A new forest policy of allocating forestland to individual households for management and development, has been applied in Vietnam since the early 1990s. This study was designed to examine how local forest-related people have used forestland and forest resources under the new policy, and to determine their level of dependency on forests. An upland forest-related community in northern central Vietnam, where the policy was introduced in 2002, was chosen as a case study. It was found that local residents in the community have not complied with the forest allocation policy well, in that they violated the policy to freely lend forestland to and borrow from villagers for cropping purposes, regardless of whether they were rich or poor, had enough land or not, or were legally forest recipients. Regarding forest dependency, all households studied lived on forest resources (forestland and forest products). More than 65% of the total annual income of poorer households was derived from the forest, compared to less than 40% for the richer households. Forest-derived income accounted for more than 75% in their total income in some of the poorest households.
Nguyen Vinh QuangEmail:
  相似文献   
895.
In the winter of 1997-1998, we collected parasitological data from 60 wild carnivora in the north-western part of Tohoku region, Japan. These included 7 foxes (Vulpes vulpes japonica), 20 raccoon dogs (Nyctereutes procyonoides viverrinus), 29 martens (Martes melampus melampus), 3 weasels (two Mustela sibirica itatsi and one M. nivalis namiyei), and one Japanese badger (Meles meles anakuma). Roundworms (Toxocara canis in foxes and Toxocara tanuki in raccoon dogs), hookworms (Ancylostoma kusimaense and Arthrostoma miyazakiense) and Molineus sp. in the small intestine were the most prevalent in foxes and raccoon dogs. In martens, Aonchotheca putorii in the stomach, Concinnum ten in the pancreatic duct, Molineus sp. and Euryhelmis costaricensis in the small intestine were the most prevalent. Collected parasites include some new helminth species for this region or Japan; the strobilar stage of Taenia polyacantha from foxes, Pygidliopsis summa from a raccoon dog, Eucoleus aerophilus, A. putorii, and Soholiphyme baturini from martens.  相似文献   
896.
A 6-year-old female mongrel dog weighing 9.0 kg was presented ananastatic, with clouding of consciousness, bilateral loss of hearing and depressed reactivity of the eyes to light. Magnetic resonance imaging (MRI) examination showed that the calvaria was markedly thickened with compression to the cerebrum and cerebellum. The case of a dog with thickened calvaria with compression of the cerebrum and cerebellum which could not be diagnosed by conventional measures was amenable to diagnosis by MRI. With increased application of MRI examination, such canine cases might increase in number.  相似文献   
897.
Sturgeon can synthesize -ascorbic acid (vitamin C) as they possess in their kidney -gulono-1,4-lactone oxidase, the enzyme catalyzing the last step of AA biosynthesis. The effect of increasing dietary ascorbic acid on gulonolactone oxidase activity was studied in lake sturgeon. Two-year-old lake sturgeon (body weight 253±89 g) were fed in triplicate groups with casein-based semipurified diets supplemented with either 0, 50, 250 or 1250 mg ascorbic acid/kg in the form of ascorbyl-2-monophosphate Mg for 38 days at 19.8°C. At the end of the trial, there were no significant differences in growth rate and survival among groups. Tissue total ascorbic acid concentrations increased significantly with dietary ascorbic acid. Renal gulonolactone oxidase activity was inconsistently affected by dietary treatment. These results suggested that, in sturgeon kidney unlike in the livers of ascorbic acid-synthesizing mammals, dietary ascorbic acid did not exert a negative feedback control on gulonolactone oxidase activity and thus on ascorbic acid synthesized. Using in vitro kinetics data we estimated a theoretical biosynthetic rate of ascorbic acid of 17 μmol (or 3 mg) per kilogram body weight per day at 15°C in juvenile lake sturgeon.  相似文献   
898.
899.
900.
A potassium permanganate-dilute sulfuric acid KMnO4/dilute H2SO4 oxidation procedure was developed to supplement Florisil cleanup of some vegetable extracts. Following sample preparation and Florisil cleanup, a reaction mixture of the n-hexane eluate from the Florisil cleanup, 4% KMnO4, and 40% H2SO4 (1 + 1 + 1) was shaken in a test tube 2 min at room temperature and then centrifuged. The n-hexane phase was washed with 2 mL 0.1N NaOH and analyzed by GLC. Twelve chlorinated pesticides were completely recovered in the n-hexane phase. Aldrin was not recovered because its extreme instability caused it to decompose even in neutral solutions. Chlorinated pesticide residues in onion, garlic, carrot, and radish root were easily analyzed by the application of this oxidation procedure.  相似文献   
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