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1.
Summary About 1 pmole of acid per egg is released when prophasic oocytes undergo maturation under the action of sperm, proteases or ionophore A 23187. No similar acid release occurs at fertilization of matured oocytes. These findings are compared with data onUrechis and sea urchin.  相似文献   

2.
Summary Acid phosphatase activity was localized at the periphery of the yolk globules in the egg of the teleost,Catostomus commersoni. In addition, a 3-fold increase in acid phosphatase activity was associated with fertilization and pronucleus formation.I thank Dr C. W. Huver for use of facilities.  相似文献   

3.
Summary Changes in liver acid hydrolase activities during the infection of albino rats,Mastomys or mice withPlasmodium berghei are described. B-Glucosidase, B-galactosidase and N-acetyl-B-D-glucosaminidase exhibited widely different responses with acid phosphatase and cathepsin-B the least responsive and are likely to be causally related to immunity of animals.  相似文献   

4.
Summary An attempt has been made to localize alkaline and acid phosphatase activities in the skin ofMystus vittatus by using histochemical techniques. The alkaline phosphatase activity is found in metabolically active cells such as basal columnar cells, mucous cells and polygonal support cells. The acid phosphatase activity is intense in the outermost squamous support cells and in the basal columnar cells. These activities have been correlated with some physiological functions of the epidermis.Acknowledgment. We are thankful to P. Vishwanatham, Government College, Mhow, and Dr R.S. Shrivastava, Holkar Science College, Indore, for providing laboratory facilities and to the Council of Scientific and Industrial Research, New Delhi, for a fellowship for M.S.  相似文献   

5.
Summary It was possible to separate species and complexes of species in theReticulitermes genus of Western Europe using esterase 3 and acid phosphatase 2.  相似文献   

6.
Summary Phenotypes of acid phosphatase with low enzymatic activity (ACP1 A and BA) are correlated with the highest degree of body mass increase observed in a sample of obese children. Since acid phosphatase probably functions as a flavin-mononucleotide phosphatase, differential modulation of flavo-enzyme activity and energy metabolism due to acid phosphatase genetic variability may explain the observed association.  相似文献   

7.
Summary The level of the acid hydrolases -glucuronidase (EC 3.2.3.11), acid phosphatase (EC 3.1.3.2) and acid protease (EC 3.4.4) was studied during larval growth and molting inP. ricini. The level of activity of these enzymes remained low during larval growth; however, the level increased sharply at the time of molting and declined sharply thereafter in the newly ecdysed insect. Interestingly, the diminished activity of these enzymes was almost quantitatively recovered in the cast-off cuticle. The excretion of acid hydrolases through the cast-off cuticle has hitherto not been reported in insects during molting.  相似文献   

8.
Summary Starvation resulted in a regular and continuous decrease in the serum acid phosphatase levels of the freshwater catfishClarias batrachus. The levels were found to be inversely proportional to the length of starvation. A maximal loss of 80.6% was noted at the end of the 5th month of starvation.The author is grateful to Dr R. S. Tandon, Dept. of Zoology, Lucknow University, Lucknow, for valuable guidance and suggestions.  相似文献   

9.
Summary The distribution of alkaline phosphatases has been studied in male and female gonads of some isopod crustaceans by means of Gomori's reaction.Monophosphatases are found on all Feulgen-positive nuclear structures, in the nucleolus and in the cytoplasm of young oocytes. They disappear from the cytoplasm in auxocytosis, during yolk formation, although they persist in the germinal vesicle. The authors think that the cytoplasmic localization is coincident with ribonucleic acid distribution.From the experiments related in the following note, nucleolar phosphatases appear to be in some way different from the nuclear (sensu stricto) and cytoplasmic phosphatases.Diphosphatases do not follow so closely the nucleic acid localization. They are absent from cytoplasm; in the nucleolus they are not distributed uniformly but show characteristic structure; in the nucleus they are not localized in the chromosomes but homogeneously diffused.  相似文献   

10.
Rana oocytes have previously been shown to contain much more soluble tubulin than does the brain, suggesting different assembly and disassembly dynamics of frog oocyte tubulin compared to that in brain. By using centrifugation, SDS-PAGE, two-dimensional gel electrophoresis and Western blots, probed with anti-α-tubulin monoclonal antibodies, polymorphic α-tubulins (isoforms) were compared in brains and follicle-enclosed oocytes of northern (Rana pipiens) and southern (R. berlandieri) frogs. Oocyte tubulin in both species had isoforms with greater ranges of isoelectric point (pI) than those of brain tubulins; in particular, the oocyte tubulin pIs ranged further into the acidic region of the isoelectric-focusing gels than corresponding brain tubulin. This difference may, in part, be responsible for the previously reported assembly differences between oocyte tubulin (undetectable assembly) and brain tubulin (high assembly). Isoforms of α-tubulin with relat ively acidic pI were more abundant in northern frog brain and oocyte soluble extracts than in analogous extracts from southern frogs. Furthermore, additional acidic α-tubulin isoforms were found in progesterone-treated oocytes (i.e., eggs), indicating increased heterogeneity of acidic a-tubulin isoforms during oocyte meiotic maturation. Among northern frog oocyte soluble components fractionated on Superose-6b columns, tubulin complexes with apparent molecular mass of about 1800 kDa were found to contain acidic α-tubulin isoforms while the putative oligomeric tubulins with an apparent molecular mass of about 250 kDa contained an additional relatively basic α-tubulin isoform. The acidic α-tubulin isoforms, therefore, are proposed to be associated with cold-adaptable cells of brain and oocytes, and may also be involved in stabilization of large soluble tubulin complexes in oocytes of the northern frog. Received 1 October 2002; accepted 9 October 2002 RID="*" ID="*"Corresponding author.  相似文献   

11.
Summary The incorporation of tritiated uridine into the follicular epithelium of degenerating oocytes of the zebrafish,Brachydanio rerio, was studied by radio-autography. After incubation times from 1–12 h, the labelling of the follicular epithelial cells of degenerating oocytes was several times higher than in normal developing follicles. This indicates an increase of RNA-synthesis, probably necessary for the formation of lytic enzymes.  相似文献   

12.
Summary During the development ofBombyx mori (monovoltin race) ecdysteroid levels were determined in oocytes, eggs, and haemolymph of larvae, and in the haemolymph of pupae. In haemolymph, the only RIA reactive materials are ecdysone and ecdysterone. In oocytes and eggs, other ecdysteroids are also detected. During larval instars, the ecdysteroid levels are low whereas they are very high during morphogenetic periods. During embryonic diapause, the ecdysone titer decreases during the cessation of morphogenesis.  相似文献   

13.
Summary TwoAmyclina species were examined concerning the more significant anatomo-morphological differences and the different cytological aspects in the nucleoli of growing oocytes.  相似文献   

14.
Summary The reproductive activity of virgin females of anAcanthoscelides obtectus strain originating from the high Colombian plateau was variable. Some females did not synthesize vitellogenin during imaginal life while others produced mature oocytes. In the case of virgin females without reproductive activity, the supply of pollen in the adult diet did not stimulate synthesis and incorporation of vitellogenin. On the other hand, the supply of pollen always induced a higher vitellogenin titre in the haemolymph of females which produced oocytes, and stimulated ovarian production.  相似文献   

15.
Direct observations of the enzymatic hydrolysis of C10 acyclic allylic isoprenyl diphosphates by an acid phosphatase from the leaves ofCinnamomum camphora (camphor tree) were made using1H and31P NMR spectrometers. The measurements indicated that the allylic primary diphosphates, geranyl diphosphate and neryl diphosphate, were hydrolyzed to their corresponding alcohols in a sequential manner via their corresponding monophosphates, whereas the allylic tertiary diphosphate, linalyl diphosphate, was hydrolyzed only to its corresponding monophosphate.  相似文献   

16.
G Peaucellier 《Experientia》1978,34(6):789-790
ABout 1 pmole of acid per egg is released when prophasic oocytes undergo maturation under the action of sperm, proteases or ionophore A 23187. No similar acid release occurs at fertilization of matured oocytes. These findings are compared with data on Urechis and sea urchin.  相似文献   

17.
Summary Large nuclear blebs have been observed in oocytes of the fish,Clarias batrachus. The bleb, which contains nucleoplasm, is finally extruded from the nucleus. The extruded body is DNase-sensitive, and it implies that some amount of DNA is extruded from the nucleus of these oocytes.Acknowledgments. We are thankful to Dr. R.K. Sharan, Department of Zoology, Patna University, for providing laboratory facilities, and to Dr V.G. Jhingran and Dr P.V. Dehadrai of ICAR for their keen interest in the work.  相似文献   

18.
Phenotypes of acid phosphatase with low enzymatic activity (ACP1 A and BA) are correlated with the highest degree of body mass increase observed in a sample of obese children. Since acid phosphatase probably functions as a flavin-mononucleotide phosphatase, differential modulation of flavo-enzyme activity and energy metabolism due to acid phosphatase genetic variability may explain the observed association.  相似文献   

19.
Summary The serum alkaline and acid phosphatases were examined in male rats between the ages of 20 and 300 days, using the method ofHuggins andTalalay 4. The activities of acid and alkaline phosphatases increase significantly to the age of 45 days, followed by a highly significant decrease up to 120th day for alkaline and to 75th day for acid phosphatase. After castration, highly significant increases in the acid, but no changes in the alkaline serum phosphatase were observed.  相似文献   

20.
Summary In hypothalamic neurosecretory nuclei of rats subject to water withdrawl for 1–14 days, a marked increase in the activities of histochemically detected acid phosphatase, thiamine pyrophosphatase and glucose-6-phosphate dehydrogenase is observed. LDH and SDH activities do not change. Two different cell types can be distinguished by means of the acid phosphatase and TPPase reactions.  相似文献   

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