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51.
52.
Preliminary report on coated charcoal immunoassay of human chorionic "growth hormone-prolactin" and growth hormone 总被引:3,自引:0,他引:3
53.
Litigation for personal injury following accidental trauma is an expensive and confused process involving three protagonists: patient, doctor and lawyer. Although post-traumatic conditions can be elaborately classified, the intrinsic validity of such classifications is often questionable. Current methods of evaluating psychological sequelae of accidental injury are inaccurate and unsatisfactory, partly because of the protagonists'' conceptual, motivational and semantic differences. In addition, there is no really satisfactory method of (a) determining and quantifying minor but significant degrees of brain damage, (b) distinguishing these from “post-traumatic neurosis”, or (c) determining the relationship between the trauma and subsequent disturbance of function. Increasingly “expert” advice is solicited but owing to the nature of the data and conditions of examination, such advice does little to clarify the underlying problems. Furthermore, doctors are often unable to communicate effectively to the judiciary just how the trauma has affected the patient. Even though certain suggestions for improvement are advanced, the need for comprehensive, longitudinal research is inescapable. 相似文献
54.
55.
Changes in fungi with age. II. Respiration and respiratory enzymes of Rhizoctonia solani and Sclerotium bataticola 总被引:1,自引:1,他引:0
Van Etten, James L. (University of Illinois, Urbana), H. Peter Molitoris, and David Gottlieb. Changes in fungi with age. II. Respiration and respiratory enzymes of Rhizoctonia solani and Sclerotium bataticola. J. Bacteriol. 91:169-175. 1966.-The rate of respiration of Rhizoctonia solani and Sclerotium bataticola decreased with age. This decrease in respiratory rate might be produced by a decrease in the specific activity of one or more enzymes involved in carbohydrate metabolism. Specific activities in cell-free extracts were measured for most of the enzymes in the hexose monophosphate shunt, Embden-Meyerhof-Parnas pathway, tricarboxylic acid cycle, and terminal electron-transport system. In addition, glucose oxidase, isocitritase, and malic enzyme were measured. In R. solani, increases in activity with age occurred for hexokinase, alpha-glycerolphosphate dehydrogenase, malic dehydrogenase, and cytochrome oxidase. Decreases occurred for phosphohexokinase, aconitase, nicotinamide adenine dinucleotide-specific isocitric dehydrogenase, reduced nicotinamide adenine dinucleotide oxidase, and at least one of the enzymes between 3-phosphoglycerate and pyruvate. In S. bataticola, increases in activity with age were observed for phosphohexokinase, pyruvic dehydrogenase, fumarase, malic dehydrogenase, and malic enzyme, whereas none of the enzymes decreased. The specific activities of the remaining enzymes did not change with age in either fungus. 相似文献
56.
Marion Barclay R. K. Barclay V. P. Skipski Olga Terebus-Kekish C. H. Mueller Ellen Shah W. L. Elkins 《The Biochemical journal》1965,96(1):205-209
1. Lipoproteins were measured in sera from 11 young women having a similar environment and diet. Sera were obtained at weekly intervals over a 12-week period. The values of the lipoproteins during periods in the normal ovulatory cycle were compared to assess their relation to reported hormone concentrations in blood. 2. Only the 4–0sf (HDL2) (d 1·125 sodium chloride) fraction changed significantly; it increased at ovulation in ten of the 11 subjects and fell as menstruation approached. 3. There was greater variability in most of the low-density rather than the high-density lipoproteins within individuals. The lipoprotein class most characteristic for an individual was the 4–0sf or HDL2 fraction. 相似文献
57.
Jean-Louis Connat Ellen Marie Dotson Peter Allan Diehl 《Archives of insect biochemistry and physiology》1989,10(3):I-XV
Fifth (last) instar nymphs of th e tick Ornithodoros moubata convert ingested 20-hydroxyecdysone (20E) to apolar conjugates AP2, which are then converted to th e more polar conjugates API. Only small quantities of free hormone were transferred to th e hemolymph and the carcass within t h e first 2 days after the blood meal. The proportion of radiolabel in these two compartments was highest at the time of the endogenous ecdysteroid peak; however, no traces of free [3H]20E were detected. The conversion probably occurs principally in the intestinal cells. Eleven days after ingestion, 84% of the radiolabel is located in the digestive tract, mainly in the form of API conjugates. API obtained in second instar nymphs fed with [3H]ecdysone ([3H]E) remain stable throughout the following nymphal instars. The ecdysteroid moiety of APT remained unchanged. The hydrolysis, although not complete, always yielded a peak comigrating with the reference E but never 20E or any other clearly distinct peaks that may have corresponded to metabolites of 20E. Less label per individual was present in adults, but its nature remained the same, viz., API mainly located in the digestive tract. In females, 2.5% of the label was transferred to the progeny during the first ovipositional cycle. Apolar products (mainly AP2) that accumulated in eggs of females injected with [3H]E or [3H]20E during vitellogenesis remained unchanged during the whole embryonic development. During the molting cycle of larvae, there was only a slight conversion of AP2 to API, but esterase hydrolysis of these products released the same percentages of E and 20E as in the freshly laid eggs. We conclude that in this tick species apolar conjugates of ecdysteroids are inactivation metabolites that are not reutilized during the development of the animal. These metabolites are mainly retained in the tick, probably because of its peculiar blocked midgut. Several studies have shown that in other arthropod species (ticks, spiders, and insects), these apolar metabolites are excreted in the feces. 相似文献
58.
Jacqueline Jollès Ellen M. Prager Emad S. Alnemri Pierre Jollès Ibrahim M. Ibrahimi Allan C. Wilson 《Journal of molecular evolution》1990,30(4):370-382
Summary Complete amino acid sequences are presented for lysozymesc from camel and goat stomachs and compared to sequences of other lysozymesc. Tree analysis suggests that the rate of amino acid replacement went up as soon as lysozyme was recruited for the stomach function in early ruminants. The two lysozymes from goat stomach are the products of a gene duplication that probably took place before the divergence of cow, goat, and deer about 25 million years ago. Partial sequences of three lysozymes from goat tears indicated that (a) the goat tear family of lysozymes may have diverged from the stomach lysozyme family by an ancient duplication and (b) later duplications are probably responsible for the multiple forms of tear and milk lysozymes in ruminants. 相似文献
59.
Variants of a cloned laboratory stock of the trypanosomatid parasite Crithidia luciliae have been distinguished from "parental type" organisms. These variants accumulated spontaneously over time as the protozoan was maintained by continuous passage in a chemically defined medium. Cloned lines of these variants have been isolated by plating on nutrient agar and partially characterized on the basis of their growth characteristics in culture, their colony and cellular morphology as well as their surface protein expression. One cloned line consisted of motile, flagellated forms which, unlike "parental type" organisms, did not adhere to the surface of culture flasks. Another cloned line was composed of non-adherent, nonmotile, amastigote-like forms which were further distinguished from "parental type" cells by virtue of their constitutive expression, in nutrient-replete medium, of high levels of a surface membrane associated 3'-nucleotidase/nuclease (3'-N'ase) activity. Both the motile, flagellated and amastigote-like variants, like the "parental type" organisms, exhibited elevated levels of the 3'-N'ase activity upon exposure to purine starvation conditions. The variants described are of potential importance in elucidating the mechanism of induction of the highly regulated 3'-N'ase activity as well as for understanding the cytoskeletal systems and the surface properties of these protozoa. 相似文献
60.
The role of indole-3-butyric acid (IBA) in adventitious root formation was studied by analyzing the uptake and subsequent metabolism of IBA in shoots of M.26 apple (Malus pumila Mill.) rootstock grown in vitro. Roots were induced by exposing shoots to 4 M IBA and [3H]IBA for 5 days in the dark and then transferring them to plant growth regulator (PGR)-free medium in the light until roots formed. Approximately 50% of the total radioactivity applied was taken up from the agar medium by the shoots during the 5-day incubation period in IBA. Indole-3-butyric acid metabolism was studied by extraction and high-performance liquid chromatographic (HPLC) separation of [3H]IBA and metabolites from the basal sections of treated shoots. The major [3H]IBA metabolite co-eluted with authentic [14C]indole-3-acetic acid (IAA) suggesting that IBA was converted to IAA in the shoots. The proportion of newly synthesized IAA present as conjugates was higher at the end of the 5-day IBA treatment period than after 13 days in PGR-free medium. There appeared to be no conjugation of IBA at any time. 相似文献