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71.
The present paper discusses three Japanese species of Pteromalidae reared from cocoons of the rice beetle Oulema oryzae (Kuwayama, 1929) (Coleoptera, Chrysomelidae). Pteromalus cyclostomus Ishizaki sp. nov. is described. Spaniopus monospilus (Thomson, 1878) and Usubaia liparae Kamijo, 1983 are newly recognized as parasitoid wasps of O. oryzae , and the former is also recorded from Japan for the first time. Pteromalus bifoveolatus Förster, 1861 is also newly recorded from Japan, with a new host record from Samia cynthia pryeri (Lepidoptera: Saturniidae).  相似文献   
72.
Infraciliature and morphogenesis of six rumen ciliates, Ostracodinium mammosum, O. munham, O. dilobum, O. rugoloricatum, O. iwawoi, and O. tiete are described from pyridinated silver carbonate-impregnated specimens. These six Ostracodinium have a similar polybrachykinety arrangement, distinct from that of other ophryoscolecid ciliates and intermediate between those of O. gracile and 0. damaliscus. Buccal infraciliature is composed of three polybrachykineties, a kinety loop, and paralabial kineties. Small dorso-adoral polybrachykinety, slender vestibular polybrachykinety, and kinety loop are characteristic. Dorsal infraciliature consists of the dorsal polybrachykinety that extends laterally along the dorsal side of the body. Morphogenesis is different from that of O. gracile, because the right end of ventral primordium extends dorsally to grow into a right primordium without separation.  相似文献   
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74.
Leishmania of the braziliensis complex were isolated from various members of the squamiventris series sandflies, including Psychodopygus chagasi (Costa Lima), P.s.maripaensis (Ready et al.), P.s.squamiventris (Lutz & Neiva), and also P.ayrozai (Barreto & Coutinho) and Lutzomyia umbratilis Ward & Fraiha. Three different serodemes of Le.b.guyanensis Floch were isolated from Lu.anduzei Rozeboom, Lu.umbratilis and Lu.whitmani Antunes & Coutinho, simultaneously captured in the same area. Unidentified Leishmania were isolated from P.claustrei Abonnenc et al., and trypanosomes from Lu.pinottii Damasceno & Arouck and an unidentified species of Lutzomyia. A naturally infected female P.s.maripaensis transmitted a braziliensis complex Leishmania, by bite, to a hamster.  相似文献   
75.
The objectives of this paper are to describe 1) the developmentof new research systems for biochemical comparison of cellulartraits between normal and tumorous pigment cells of fish origin,2) the similarity and dissimilarity between these two categoriesof pigment cells with regard to growth, differentiation andpigment translocating activities and 3) the potentials of thesetumorous pigment cells to manifest multiple differentiation.The development of research systems has been achieved by theestablishment of 1) methods to obtain homogenous populationsof viable, cultivatable xanthophores (erythrophores) and melanophoresfrom goldfish skins, 2) permanent cell lines from goldfish erythrophoromas(tumors derived from erythrophores) and from Nibe croaker irido-melanophoromas(tumors composed of mixed populations of iridophore- and melanophore-likecells) and 3) procedures to induce differentiation in normaland tumorous stem cells (including the formation of pigmentsand ability to undergo pigment translocation in response tocAMP, to the neurotransmitter epinephrine and to the hormonesACTH and melatonin). Two kinds of tumorous pigment cell linesexamined herein have the ability to form, in addition to variouspigments, structures similar to dermal skeletons and lentoidbodies. These findings strongly suggest the possibility thatthese fish pigment cell tumors are neural crest stem cell tumorsin nature.  相似文献   
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77.
In the swimming phase of the larvae of the ascidian, Halocynthia roretzi , changes in the activity of acid phosphatase (AcP-ase) were studied cytochemically with respect to the appearance of metamorphosing potencies. The AcP-ase activity in the larvae before and soon after hatching is weakly visible only in and around the nuclei of the epithelial, muscular and notochordal cells. 6 hr after hatching the enzyme activity begins t o appear weakly in the microblasts around the proximal end of the notochordal sheath, whereas the activities which were found in the previous stages disappear. In the larvae which passed for 12 hr after hatching, the activity of AcP-ase is distinctly shown in the microblasts and also in the other 2 mesodermal cells, meso- and macro- blasts. The microblasts of this stage are closely attached to the notochordal sheath at the proximal end. At the same time, many large granules which appear similar to lysosomes are found in the microblast by an electron microscopy. The 6th hour's larvae after hatching can be induced slowly to resorb its tail by the treatment with a nile blue solution, but the time which it takes for tail resorption is gradually shortened depending on the age of the larva up until 12 hr after hatching.
From these results, i t was concluded that the appearance of the AcP-ase activity in the microblasts was parallel with the appearance of the potency of metamorphosis of the larvae after hatching. Possible roles of the microblasts at onset of meta- morphosis would seem to play a role in the rupture of the notochordal sheath and in the succeeding regression of the tail tissues.  相似文献   
78.
Glucose utilization by spermatids was found to be 17.37±0.37 nmoles/hr/106 cells at 34°C and 28.94±1.12nmoles/hr/106 cells at 40°C. A good parallelism was observed between the increased rate of glucose utilization and lactate production at 40°C. There was no significant change in the levels of glycolytic intermediates in the cells, except for marked accumulations of fructose-1, 6-diphosphate, dihydroxyacetone phosphate and glyceraldehyde-3-phosphate in the presence of glucose (1 mM). Glucose oxidation in the citrate cycle by spermatids was higher at 40°C than at 34°C, but was never greater than 2% of the overall rate of glucose utilization. In addition, glucose did not prevent decrease of ATP at either 34 or 40°C. The effects of temperature on the activities of 11 glycolytic enzymes were examined. The activities of aldolase and phosphoglyceromutase were similar between 30 and 34°C, but increased markedly at 40°C. The higher temperature increased the Vmax values, without affecting the Kms. The activities of other glycolytic enzymes were similar at the different temperatures. These findings indicate that the increased overall rate of glucose utilization in glycolysis at higher temperature is due to increased Vmax values of aldolase and phosphoglyceromutase.  相似文献   
79.
Helminthosporol, helminthosporic acid and dihydrohelminthosporicacid stimulated hypocotyl elongation of light-grown cucumberseedlings. The relative activities of the three compounds werein the order H2-H-acid> H-acid> H-ol. The higher the dosage,the longer the promotion of the hypocotyl elongation lasted.The response of the hypocotyl to H-acid depended on the presenceof cotyledons. As the amount of the cotyledon attached to thehypocotyl was reduced, the response decreased. When IAA-oxidase was estimated as IAA metabolized per dry weightof the hypocotyl, there was an inverse relationship betweenIAAoxidase activity and H-ol-induced elongation of the hypocotyl.However, there was no difference between control and H-ol treatedmaterials when IAA metabolized per plant was compared. It isunlikely that the mechanism of H-ol action is closely relatedto IAA-oxidase activity of the plant. (Received April 5, 1967; )  相似文献   
80.
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