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991.
D Virgintino N L'Abbate D Ribatti M Bertossi L Roncali L Ambrosi 《Biological structures and morphogenesis》1989,2(3):85-88
On the basis of previous observations on the teratogenic effects of a variety of organophosphorus and methylcarbamate compounds on the avian skeletal apparatus, the Meckel's cartilage shape and structure were analyzed in carbaryl (1-naphthyl N-methylcarbamate) treated and control chick embryos of 9, 10, 12 days of incubation. The results indicate that both during normal development and under experimental conditions these cartilages undergo similar deformities, apparently subsequent to chondroblast death and regressive processes in the extracellular matrix. Since the macro- and microscopical cartilage alterations are significantly more frequent in the treated embryos than in the controls, a hypothesis is advanced that the methylcarbamate may increase the spontaneous tendency of the above mentioned cartilaginous anlagen to be affected by degenerative processes during embryogenesis. 相似文献
992.
H N Rubin M N Halim 《Comparative biochemistry and physiology. B, Comparative biochemistry》1988,91(3):585-591
1. Rabbit globin mRNA poly(A) was translated in two cell-free synthesizing systems, rabbit reticulocyte lysate and wheat germ extract, to characterize the product released from the poly(A) tract during globin synthesis. 2. Kinetic studies indicate that the size of the cleaved nucleotide proves to be a monomer, as revealed by column chromatography on Sephadex G-100 or G-25. 3. Characterization of the monomer was accomplished by chromatography on DEAE-cellulose. Initially, 5 min post-translation, the monomer was ATP only; however, at later times ATP, ADP, AMP and adenosine were detected. 4. The two synthesizing systems differed in that globin mRNA poly(A) was translated at a faster rate in the wheat germ extract as revealed by the appearance of ATP, whereas AMP was detected sooner in the rabbit reticulocyte lysate. 5. The results indicate that the A unit released from the poly(A) tract during mRNA poly(A) translation is a monomer, and that these metabolites may play a role in controlling protein initiation via the released ATP. 相似文献
993.
The capacity of spleen, thymus, and bone marrow cells of intact (control) and of hydrocortisone-treated mice CBA to induce the lymph node type of graft-v-host reaction (GVHR) in hybrids F1 (CBA X c57bl) was studied. After hydrocortisone injection (2.5 mg per mouse) the donor spleen cells became more active in GVHR, considering the value of lymph node indices and immunoblast content in the regional lymph node as compared with a control group. Following transplantation of thymus cells taken from the hydrocortison-treated donors the immunoblast count was higher, although the lymph node weight remained the same as in the control group. On the contrary, following the transfer of the bone marrow cells from the hydrocortisone-treated mice the lymph nodes enlarged, while the immunoblast count remained as low as in control. Consequently, exogenously conditioned increase in the hydrocortisone level was accompanied by an enrichment of the spleen and thymus cell populations with T-lymphocytes, proliferating in response to H-alloantigens. 相似文献
994.
Peter Van Bogaert Lieve Peremans Nadine Diltour Danny Van heusden Tinne Dilles Bart Van Rompaey Donna Sullivan Havens 《PloS one》2016,11(4)
The aim of the study reported in this article was to investigate staff nurses’ perceptions and experiences about structural empowerment and perceptions regarding the extent to which structural empowerment supports safe quality patient care. To address the complex needs of patients, staff nurse involvement in clinical and organizational decision-making processes within interdisciplinary care settings is crucial. A qualitative study was conducted using individual semi-structured interviews of 11 staff nurses assigned to medical or surgical units in a 600-bed university hospital in Belgium. During the study period, the hospital was going through an organizational transformation process to move from a classic hierarchical and departmental organizational structure to one that was flat and interdisciplinary. Staff nurses reported experiencing structural empowerment and they were willing to be involved in decision-making processes primarily about patient care within the context of their practice unit. However, participants were not always fully aware of the challenges and the effect of empowerment on their daily practice, the quality of care and patient safety. Ongoing hospital change initiatives supported staff nurses’ involvement in decision-making processes for certain matters but for some decisions, a classic hierarchical and departmental process still remained. Nurses perceived relatively high work demands and at times viewed empowerment as presenting additional. Staff nurses recognized the opportunities structural empowerment provided within their daily practice. Nurse managers and unit climate were seen as crucial for success while lack of time and perceived work demands were viewed as barriers to empowerment. 相似文献
995.
996.
At least 90% of a membrane-bound phospholipase D was solubilized by extraction of freeze-dried rat brain with 0.8% Miranol H2M and 0.5% cholate. The bulk of base exchange reaction enzymes remained firmly bound to the particulate fraction under these conditions. The phospholipase D specific activity was enriched 240-fold by a purification protocol employing ammonium sulfate precipitation, and both Sepharose 4B and DEAE-cellulose column chromatography. The approximate molecular weight of the partially purified enzyme was calculated to be 200,000 based upon the elution profile from Sepharose 4B and Sephadex G-200 columns. The optimum pH was 6.0, and Km values for phosphatidylcholine and phosphatidylethanolamine were 0.75 mM and 0.91 mM, respectively. The enzyme activity was not dependent on the presence of divalent cation although Ca2+ and Fe2+ showed stimulatory effects. 相似文献
997.
M S Berdinskikh A S Kiseleva P N Kosiakov 《Biulleten' eksperimental'no? biologii i meditsiny》1985,100(7):55-57
Peritoneal macrophage cultures from intact mice and those immune to influenza virus A/PR/8/34 (HON1) were infected with homologous virus or influenza virus A/England/42/72 (H3N2) whereupon virus was isolated from chick embryos. It was established that in intact macrophages, both viruses duplicated similarly. Macrophages immune to virus HON1 equally disintegrated both in homologous virus and heterologous influenza virus H3N2. 相似文献
998.
N. Hayashi M. Sholichin T. Sakao Y. Yamamura H. Komae 《Biochemical Systematics and Ecology》1980,8(2):109-113
A survey of chemical composition of 23 species of Asarum subgenus Heterotropa showed that the five groups could be distinguished on the basis of the presence or absence of asatone, phenol ethers and terpenes. 相似文献
999.
N Shamala L W Lim F S Mathews W McIntire T P Singer D J Hopper 《Journal of molecular biology》1985,183(3):517-518
Single crystals of p-cresol methylhydroxylase, a flavocytochrome c from Pseudomonas putida, have been prepared. The crystals are orthorhombic, space group P212121 with unit cell parameters; a = 140.3 A, b = 130.6 A and c = 74.1 A. They contain a single non-symmetric dimer per asymmetric unit and diffract to at least 2.5 A resolution. 相似文献
1000.
A N Mats E V Cheprasova S I Elkina E V Koriakin 《Zhurnal mikrobiologii, epidemiologii, i immunobiologii》1987,(5):67-71
Nonspecific adhesiveness of lymphocytes to polyacrylonitrile fiber and the antigen-specific adhesiveness of T-lymphocytes to Shigella flexneri pellicular immunosorbent have been studied in dysentery patients. Short courses of treatment with indomethacin, but not with thymalin (the preparation of thymic hormones), used for immunomodulation, have accelerated the normalization of nonspecific lymphocyte adhesiveness during regression of the disease, while indomethacin, in contrast to thymalin, inhibits antigen-specific T-lymphocyte adhesiveness which increases with the development of immune response. 相似文献