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91.
Vis P Della Pasqua O Kruk M Martin D Mocaër E Danhof M Jochemsen R 《European journal of pharmacology》2001,414(2-3):233-243
The pharmacokinetic-pharmacodynamic relationship of S 15535 (1-(benzodioxan-5-yl) 4-(indan-2-yl)piperazine) and its active 5-hydroxy metabolite S 32784 (1-(benzodioxan-5-yl) 4-(5-hydroxyindan-2-yl)piperazine), and buspirone as a reference, were studied in male Wistar rats using a behavioural model of anxiety by determining the reduction in the number of fear-induced ultrasonic vocalisations. S 15535 and buspirone were administered p.o. and i.v. S 32784, present in man but not in rat, was administered i.v. The pharmacokinetics and pharmacokinetic-pharmacodynamic relationships were described using non-linear mixed effects modelling. The no-drug effect was constant and all compounds were active in the model, reducing ultrasonic vocalisations immediately after administration. The sigmoid E(max) model was used to describe the pharmacokinetic-pharmacodynamic relationships, with E(max) values of a 90% decrease in baseline ultrasonic vocalisations. Corrected for plasma protein binding, all compounds showed similar potency. The study shows that ultrasonic vocalisations can be considered a suitable endpoint for the anxiolytic effect when used in conjunction with non-linear mixed effects modelling to overcome the limited sampling and effect measurements. 相似文献
92.
Kruk B Chmura J Krzeminski K Ziemba AW Nazar K Pekkarinen H Kaciuba-Uscilko H 《Psychopharmacology》2001,157(2):197-201
RATIONALE: The effects of caffeine on psychomotor performance have been evaluated under resting conditions and in a thermoneutral environment. Our hypothesis was that these effects could be modified by factors enhancing the level of alertness, such as exercise and cold exposure. OBJECTIVE: The purpose of this study was to follow up changes in the multiple choice reaction time (RT) during exercise at room and low ambient temperatures after caffeine or placebo administered in a double blind manner. METHODS: Nine soccer players performed multistage, incremental exercise until volitional exhaustion on a bicycle ergometer at 22 degrees C or 4 degrees C, 1 h after ingestion of coffee with caffeine (CAF) or without it (PL). Immediately before exercise and at the end of each workload, RT and blood lactate (LA) were measured. Oxygen uptake (VO2) and heart rate (HR) were recorded continuously. Blood LA threshold and the workload associated with the shortest RT were determined. RESULTS: During exercise at 22 degrees C, RT was significantly shorter in CAF than in the PL test, while at 4 degrees C there were no differences in RT between CAF and PL trials. Cold exposure did not affect RT either at rest or during exercise. Neither caffeine nor cold exposure influenced the maximal VO2, the maximal HR and LA threshold. CONCLUSION: In the thermoneutral environment, caffeine ingestion improved psychomotor performance during exercise, whilst at low ambient temperature this effect was blunted. These findings suggest that the stimulating action of caffeine depends on the level and source of arousal. 相似文献
93.
Margaret E Kruk Marta R Prescott Helen de Pinho Sandro Galea 《Human resources for health》2009,7(1):27-9
Background
There is broad policy consensus that a shortage of doctors and nurses is a key constraint to increasing utilization of essential health services important for achieving the health Millennium Development Goals. However there is limited research on the quantitative links between health workers and service coverage rates. We examined the relationship between doctor and nurse concentrations and utilization rates of five essential health services in developing countries. 相似文献94.
Margaret E. Kruk Lynn P. Freedman Grace A. Anglin Ronald J. Waldman 《Social science & medicine (1982)》2010
Violent conflicts claim lives, disrupt livelihoods, and halt delivery of essential services, such as health care and education. Health systems are often devastated in conflicts as health professionals flee, infrastructure is destroyed, and the supply of drugs and supplies is halted. We propose that early reconstruction of a functioning, equitable health system in countries recovering from conflict is an investment with a range of benefits for post-conflict countries. Building on the growing literature about health systems as social and political institutions, we elaborate a logic model that outlines how health systems may contribute not only to improved health status but also potentially to broader statebuilding and enhanced prospects for peace. Specifically, we propose that careful design of the core elements of the health system by national governments and their development partners can promote reliable provision of essential health services while demonstrating a commitment to equity, strengthening government accountability to citizens, and building the capacity of government to manage core social programs. We review the conceptual basis and extant empirical evidence for these mechanisms, identify knowledge gaps, and suggest a research agenda. 相似文献
95.
Casanueva FF Molitch ME Schlechte JA Abs R Bonert V Bronstein MD Brue T Cappabianca P Colao A Fahlbusch R Fideleff H Hadani M Kelly P Kleinberg D Laws ED Marek J Scanlon M Sobrinho LG Wass JAH Giustina A 吴哲褒 张亚卓 《中华神经外科杂志》2008,24(8)
3.男性:高催乳素血症通常导致阳痿、不孕和性功能低下.男性患者通常为大腺瘤,有神经系统症状.其原因可能是对症状认识的延误或者肿瘤生物学行为的差异. 相似文献
96.
Speech-controlled generation of radiology reports 总被引:1,自引:0,他引:1
Robbins AH; Horowitz DM; Srinivasan MK; Vincent ME; Shaffer K; Sadowsky NL; Sonnenfeld M 《Radiology》1987,164(2):569-573
Voice entry has been successfully employed to generate radiology reports with a word recognizer with a 1,000-word lexicon capacity. About 50% of reports were able to be dictated with a single 900-word lexicon. This was split into five sections by anatomic or subspecialty application. Each was augmented to 900 words. By switching from one lexicon to another, it was possible to dictate more than 70% of reports. With exclusive use of three lexicons in subspecialty areas (gastrointestinal radiology, neuroradiology, and mammography), and with further modification of the respective vocabulary, it has been possible to employ the system 88% of the time. Twelve percent of cases included wording that was beyond the scope of the lexicon. Computer subsets that allow different translations of some words when used in different contexts have been used. Some of these are used as triggers that will print whole lines, sentences, or even complete reports. Dictation times with voice entry take about 20% longer. Recognition reliability has been greater than 95%. 相似文献
97.
Platelets secrete a low-molecular-weight protein, platelet factor four (PF-4), which binds to and neutralizes heparin and related sulfated glycosaminoglycans (GAGs). To examine the interactions of PF-4 with the GAGs present on endothelial cell surfaces, we incubated 125I-PF-4 with cell suspensions derived from confluent monolayers of cultured bovine aortic endothelium. Binding of 125I-PF-4 was inhibited by a 100-fold excess of nonradioactive PF-4 and varied with duration and temperature of incubation. At 4 degrees C, binding reached equilibrium at 20 minutes with kd = 2.87 mumol/L and Bmax of 63.83 pmol/10(5) cells. Binding capacity was reduced 83.4% by brief incubation of endothelial cells with trypsin and 46.67% by incubation with Flavobacterium heparinase, but was unchanged by chondroitin-ABCase treatment. At 37 degrees C, PF-4 was internalized by confluent monolayer of bovine aortic endothelial cells primarily through low-affinity adsorptive endocytosis. The internalized PF-4 was degraded to amino acids and small peptides with 50% conversion after 18-hour incubation. These studies demonstrate that a secreted platelet protein can bind to and enter endothelial cells. Binding may explain the rapid clearance of released PF-4 from plasma and could have important local effects on endothelial structure and function. 相似文献
98.
We characterized neutrophil autoantigens using an immunoblotting technique with antibodies obtained from patients with autoimmune neutropenia. These results were correlated with serologic characterization of the antibodies, using indirect immunofluorescence and leukoagglutination. Of the 17 sera immunoblotted, 16 showed discrete bands in the molecular weight range of 30 to 112. Three patients with Felty's syndrome reacted with an antigenic target of 80 to 84 Kd molecular mass, a finding not seen in any of the other patients studied. By serologic testing, none of the autoimmune sera showed serologic specificity for any known neutrophil-specific alloantigen. Using an anti-NA-1 serum, we identified antigenic targets at 40, 50, and 101 Kd in both NA-1-positive and NA-1-negative neutrophils. Ten of 17 autoimmune sera showed reactivity in this corresponding range. These studies demonstrate that immunoblotting may be used to identify antigenic targets in autoimmune neutropenia and may suggest a specificity of these antibodies not definable by serologic techniques. Correlation of immunoblot reactivity with disease states associated with immune neutropenia may be useful in the study of the pathogenesis of the different forms of autoimmune neutropenia. 相似文献
99.
Delayed hepatic CT scanning: increased confidence and improved detection of hepatic metastases 总被引:1,自引:0,他引:1
Bernardino ME; Erwin BC; Steinberg HV; Baumgartner BR; Torres WE; Gedgaudas- McClees RK 《Radiology》1986,159(1):71-74
Fifty oncologic patients with suspected hepatic metastases were prospectively evaluated by dynamic sequential hepatic computed tomography (DSHCT) and by delayed iodine hepatic computed tomography (DICT) scanning. DICT scanning was performed 4-6 hours following administration of 60 g of intravenous iodine. Both techniques were evaluated for lesion definition relative to the adjacent hepatic parenchyma and for numbers of metastases detected. Metastases were detected by both techniques in 26 patients. Fifteen patients (58%) had lesions better defined by DICT. DICT scanning detected more metastases in seven of these 15 patients. In eight patients (31%), there was no difference between the two techniques in numbers of masses detected or lesion definition. In three cases (11%), metastases were more confidently identified on the initial or DSHCT scan. DICT scanning, as described, is useful in defining and detecting hepatic metastases, especially where there is questionable hepatic involvement or better quantification of size is necessary. 相似文献
100.
V. de las Alas MD W. D. Voorhees PhD L. A. Geddes ME PhD J. D. Bourland PhD W. E. Schoenlein 《Journal of clinical monitoring and computing》1990,6(3):183-185
In 4 spontaneously breathing, barbiturate-anesthetized dogs, hyperthermia was induced with 2,4-dinitrophenol while rectal
temperature, heart rate, mean blood pressure, end-tidal carbon dioxide, and carbon dioxide production (milliliters per minute)
were measured continuously. The latter was determined with a pneumotachygraph (to obtain respired volume) and an infrared
carbon dioxide analyzer that measured inspired and expired carbon dioxide concentration. Of the five physiologic measurements,
the increase in carbon dioxide production preceded the increase in rectal temperature by more than 120 seconds. End-tidal
carbon dioxide was an unreliable indicator in the spontaneously breathing animal of approaching hyperthermia during spontaneous
breathing due to a transient tachypnea, which decreased end-tidal carbon dioxide. The carbon dioxide production (milliliters
per minute) increased immediately and reached three to five times the control value. Blood pressure and heart rate were insensitive
indicators of approaching hyperthermia. 相似文献