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51.
Acetylene Reduction Assay for Nitrogenase Activity: Gas Chromatographic Determination of Ethylene Per Sample in Less Than One Minute
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Ammoniacal silver nitrate (10 mg/ml) was added to terminate acetylene reduction assays used to measure nitrogenase activity. Silver nitrate quantitatively precipitated acetylene as the carbide salt, but did not affect the ethylene formed. The vials containing ethylene can be analyzed gas chromatographically at the rate of about 13 samples in 10 min. 相似文献
52.
Significant increase in the activity of liver succinate dehydrogenase (SDH) was observed in male Wistar rats, fed Aroclor 1260 (PCB; polychlorinated biphenyl) at 50 and 100 ppm level for 120 days. Lactate dehydrogenase (LDH) activity increased in 50 ppm PCB fed animals and decreased in 100 ppm PCB fed rats. On the other hand, enzymes like alanine and aspartate aminotransferase, alkaline and acid phosphatase showed remarkable decrease in activity in PCB fed animals. Slab gel electrophoresis of LDH isozymes showed remarkable increase in LDH2 and LDH3 and to some extent increase in LDH1 isozymes of livers of 50 ppm PCB fed animals but not in 100 ppm PCB fed groups as compared to controls. In both the PCB fed groups, liver showed centrilobular hypertrophy, hepatocellular damage, hyperplasia, karyolysis and karyorrhexis. 相似文献
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54.
The structure of a new tetracyclic triterpene isolated from the flowers of Musa paradisiaca was determined as (24R)-4α,14α,24-trimethyl-5α-cholesta-8,25(27)-dien-3β-ol. 相似文献
55.
P Adhikary J Banerji D Chowdhury A K Das C C Deb S R Mukherjee A Chatterjee 《Indian journal of experimental biology》1989,27(10):868-870
Chronic administration (sc) of the extract of the stalk of P. betle at 30 mg/kg body weight daily for 21 days produced significant decrease in oestrogen and androgen dependent target organ weights along with increase in cholesterol in adrenal, ovary and testis. Acid and alkaline phosphatase activities in serum, liver and kidney did not exhibit any toxic effect. There was marked change in morphology of testis and ovary. Vaginal smear showed prolonged dioestrus in treated female. The treated male showed decreased number and motility of sperm. Both male and female remained infertile after treatment suggesting antifertility activity of the extract on both sexes of albino rats. 相似文献
56.
The occurrence of a new steroid alkaloid in the root-bark of Holarrhena antidysenterica is reported. It is shown to be 20S-acetamido-5α-pregnan-3β-ol from spectroscopic investigations, chemical reactions, correlation with compounds of known structure and stereochemistry and subsequently by the stereo-specific synthesis from 3β-hydroxybisnorcholenic acid. 相似文献
57.
Hypothalamic and plasma dopamine--hydroxylase (DBH, EC 1.14.2.1) activities were measured by a coupled radioenzymatic method. Animals representing five experimental groups (intact controls, adrenalectomized, pinealectomized, adrenalectomized + pinealectomized, doubly sham-operated) were killed and sampled at 8 times through the 24-hr daily cycle, 15 days postoperation, and at 50–52 days of age. Hypothalamic DBH in intact control animals had statistically significant fluctuations in relation to time of day. These changes were lost or dampened in groups that had had intracranial surgery and were characteristically shifted by adrenalectomy, either alone or with pinealectomy. Plasma DBH fluctuations in the same animals resembled those in hypothalamus in some features (e.g., peak near mid-dark; shift in daily maxima and minima after adrenalectomy) and differed in others (e.g., no effect of intracranial surgery or of sham operation; adrenalectomized + pinealectomized animals resembled the solely pinealectomized). Although temporal patterns in hypothalamic DBH activity thus differed in the experimental animal groups, the daily means of hypothalamic DBH activity were similar. 相似文献
58.
Antibodies to liposomal phosphatidylserine and phosphatidic acid 总被引:1,自引:0,他引:1
Polyclonal antisera to phosphatidylserine or phosphatidic acid were induced in rabbits by injecting liposomes containing phosphatidylserine or phosphatidic acid and lipid A. Adsorption of antisera with liposomes containing different phospholipids revealed that some degree of reactivity with one or more phospholipids other than the immunizing phospholipid was often observed. However, cross-reactivity with other phospholipids was not a universal phenomenon, and one antiserum to phosphatidylserine failed to cross-react (i.e., was not adsorbed) with liposomes containing other phospholipids. All of the antisera were inhibited by soluble phosphorylated haptens (e.g., phosphocholine but not choline), but one of the antisera to phosphatidylserine was inhibited both by phosphoserine and by serine alone. Liposomal membrane composition influenced the activity of antiserum to phosphatidylserine. Regardless of whether unsaturated (beef brain) or saturated (dimyristoyl) phosphatidylserine was used in the immunizing liposomes, the antisera reacted more vigorously with liposomes containing unsaturated than saturated phosphatidylserine. We conclude that liposomes containing lipid A can serve as vehicles for stimulating polyclonal antisera to phosphatidylserine and phosphatidic acid. Although cross-reactivity with certain other phospholipids can be observed, sera from selected animals apparently can exhibit a high degree of specific activity to the immunizing phospholipid antigen. 相似文献
59.
Ambrose O Talisuna Penny Grevval Andrew Balyeku Timothy Egan Godfrey Bwire Bram Piot Renia Coghlan Maud Lugand John Bosco Rwakimari Richard Ndyomugyenyi Fred Kato Maria Byangire Paul Kagwa Fred Sebisubi David Nahamya Angela Bonabana Susan Mpanga-Mukasa Peter Buyungo Julius Lukwago Allan Batte Grace Nakanwagi James Tibenderana Kinny Nayer Kishore Reddy Nilesh Dokvval Sylvester Rugumambaju Saul Kidde Jaya Banerji George Jagoe 《Malaria journal》2012,11(Z1):O16
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