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91.
Nicoletta Desideri Isabella Sestili Maria Luisa Stein Stefano Manarini Giuseppe Dell'Elba Chiara Cerletti 《Archiv der Pharmazie》1997,330(4):100-106
6-[(4-Quinolinyl)oxy]hexanoic acids and the corresponding esters were designed and synthesized as inhibitors of the production of arachidonic acid metabolites. The inhibitory activities were assayed in vitro by evaluation of serum leukotriene B4 and thromboxane B2 production. While all 6-[(4-quinolinyl)oxy]hexanoic acids and their esters proved to be inactive, the N-alkyl-4-quinolones, obtained as by-products in their synthesis, were found to be a new class of leukotriene biosynthesis inhibitors. 相似文献
92.
依据乡村医生人力结构现状调查结果,就现阶段县级卫校在初级卫生保健中的作用及今后面向乡村医生办学的可行性作了具体的分析和探讨。结论是:提高质量,加强对在岗乡医进行系统化正规中专层次的职后复训,应是县级卫校今后1O年的最主要的任务。 相似文献
93.
94.
Mark L. Laudenslager Maria L. Boccia Christy L. Berger Mary M. Gennaro-Ruggles Britta McFerran Martin L. Reite 《Developmental psychobiology》1995,28(4):199-211
Many behavioral, immunological, and physiological consequences of brief maternal separation in bonnet (Macaca radiata) and pigtail monkeys (Macaca nemistrina) have been documented. However, the impact of social separation on plasma cortisol and growth hormone is unknown for these particular species. In the present study, the behavioral and endocrinological consequences of a 2-week maternal separation in socially housed infant bonnet and pigtail monkeys were followed. In seven pairs (separated and matched control) of bonnet and six pairs of pigtail infants, plasma was obtained under baseline, separated, and reunion conditions twice weekly for the duration of the study. Blood samples were obtained from both infants of the pair in approximately 10 min. Plasma total cortisol, free cortisol, and growth hormone were measured in these samples. Focal animal behavioral observations were made on all subjects twice daily throughout the study period. In both species, total cortisol and free cortisol rose immediately following maternal separation in comparison to the matched nonseparated controls and returned to basal levels (e.g., that of matched non-separted controls) following reunion with the mother. In contrast, plasma growth hormone rose only in the pigtail infants over a time course that peaked around the time of reunion. Multiple regression techniques indicated for the first week of separation, in the separated but not control subjects, that mean plasma free and total cortisol was positively related to distress behaviors (vocalization and postural slouch) observed during this week and negatively related to social behaviors (play and proximity to others) noted during the same period. In contrast, plasma growth hormone was related to both species and sex of the subjects but unrelated to behavioral variables. © 1995 John Wiley & Sons, Inc. 相似文献
95.
Basilio Pispisa Mariano Venanzi Antonio Palleschi Maria D'Alagni 《Macromolecular chemistry and physics.》1995,196(9):2809-2825
The photophysics of protoporphyrin-naphthyl (P-N) pairs covalently and randomly bound to the ε-amino groups of the side-chains of poly(L -lysine) (PL) were investigated by steady-state and time-resolved fluorescence measurements. The results indicate that quenching of excited naphthalene (λex = 280 nm) chiefly occurs by interconversion to the triplet state when the polymeric matrix is in random coil (pH ≈ 7) and by intramolecular electron transfer from ground-state porphyrin, P → 1N*, when the polypeptide is in α-helical conformation (pH ≈ 11), the specific rate constant of the electron transfer being 3,1 · 107 s?1 (25°C). PNPL exhibits very little exciplex fluorescence, whatever the pH, suggesting both a reduced internal Brownian motion of the chromophores, owing to the amide bond in the substituted side-chains, and a relatively large average interprobe separation distance. This agrees with polarized fluorescence data and with the results of a conformational statistics analysis on the fully ordered PNPL, indicating that the average interchromophoric distance for which the electron transfer has the highest probability to occur is around 12 Å. The computational results allowed us to reproduce the experimental fluorescence decay curves and estimate the parameters governing the electron transfer process. Implications of these findings on the relaxation time of the heli-xcoil transition in PNPL are briefly discussed. 相似文献
96.
恒河猴坐姿着陆冲击内耳损伤的观察 总被引:2,自引:0,他引:2
为研究机体及各组织器官对冲击力的耐受限值,探讨致伤原因及提出防护措施,利用着陆冲击塔,使实验动物恒河猴的坐姿状态下,进行冲击试验,试验后1h左右处死,作大体解剖观察并取心,肝,脾,肺,颞骨等组织,固定,切片,镜检。同时重点观察了内耳的损伤。结果表明,冲击载荷不大(平台过载值为≤25G)时内脏虽然有轻度损伤,但内耳可避免受员,当冲击力加大到一定程度(平台过载值为30~35G)导致内脏中等损伤时,内耳 相似文献
97.
98.
Reviews major activities of the Editor and changes in the Journalof Pediatric Psychology (JPP) for issues published in 1993 through1997. Significant trends and accomplishments are reviewed, includingthe increased use of Special Issues and Special Sections tohighlight current pediatric psychological research. Articlespublished during the term are analyzed interms of article typeand population type Comarisons are made to earlier trends inJPP publication as reported by Roberts (1 992). 相似文献
99.
Dario Roccatello Marco Formica Guido Cavalli Maria C. Amprimo Maria G. Pignatelli Paolo Costa Ruggero de Paulis Giacomo Quattrocchio rea Molino Gianbeppe Giordano 《Artificial organs》1990,14(1):69-72
Neutrophil oxidative metabolism, C3d and beta 2 microglobulin levels, were assessed in nine consecutive patients undergoing cardiopulmonary bypass surgery with polypropylene hollow fiber oxygenators for open cardiac operations. Generation of oxygen free radicals by neutrophils was measured as luminol-enhanced chemiluminescence after stimulation with opsonized Zymosan and phorbol myristate acetate. A significant increase in light emission was detected by using both of the chemiluminescence stimulators. Moreover, a remarkable and significant increase in C3d levels was found already at 10 min. Conversely minimal changes in levels of beta 2 microglobulin were detected during cardiopulmonary bypass surgery. These data suggest that the impact of the patient blood with the foreign surface of cardiopulmonary bypass results in activation of phagocyte cells with increased potential in oxygen consumption. These effects could be partially complement-mediated. 相似文献
100.
Maria Cristina Locatelli Lucilla Tedeschi Maurizia Clerici Antonella Romanelli Adelaide D'Antona Roberto Labianca Gino Luporini 《Supportive care in cancer》1996,4(3):218-219
We have reviewed the incidence of cisplatin-induced anaemia in patients affected with solid tumours treated with at least three courses of first-line cisplatincontaining regimens. In our experience, a low percentage (5%) of patients required transfusions of red blood cells. We think it is of the utmost importance to adopt uniform criteria in monitoring and treatment of patients at risk of developing cisplatin anaemia and to identify subsets of patients to eventually treat with erythropoietin. 相似文献