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21.
The involvement of dopamine (DA) receptor subtypes in the behavioral effects of CNS stimulants was studied in rats trained to discriminate occaine from saline. In substitution tests, the stimulus effects of 10mg/kg of this substance generalized tod-amphetamine (0.25–1.0 mg/kg) and the selective D2 against LY-171555 (0.05–0.25 mg/kg); but not to the D1 agonist SKF-38393 (5.0–15.0 mg/kg); in combination tests, the D1 antagonist Sch-23390 (0.0625–0.5 mg/kg) significantly blocked, and the D2 antagonist spiperone (0.25–0.5 mg/kg) partially blocked the cocaine cue. These data suggest that the involvement of DA systems in the behavioral effects of cocaine is more complex than either D1
or D2 receptor activation; for example, the stimulus properties of this substance might involve both D1
and D2 receptor activation.Some of these results were presented at the meeting of the Society for Neuroscience, Toronto, 1988 相似文献
22.
Jennifer L. King Rita J. Miller James P. Blue Jr. William D. O'Brien Jr. John W. Erdman Jr. 《Nutrition Research》2009
Epidemiological studies have shown dietary magnesium (Mg) intake and serum Mg levels to be inversely correlated with the development of atherosclerosis. We hypothesized that low levels of Mg would promote atherosclerotic plaque development in rabbits. New Zealand white rabbits (4 months old, n = 22) were fed an atherogenic diet containing 0.12% (−Mg), 0.27% (control), or 0.43% (+Mg) Mg for 8 weeks. Blood samples were obtained at baseline, 2, 4, 6, and 8 weeks and were assayed for total cholesterol, high-density lipoprotein (HDL), non-HDL, triglycerides (TG), C-reactive protein, serum Mg, and erythrocyte Mg. Aortas from −Mg had significantly more plaque, with an intima thickness 42% greater than control and 36% greater than +Mg. Serum cholesterol levels rose over time, and at 8 weeks, −Mg had the highest and +Mg the lowest total and non-HDL cholesterol and TG levels, although these results did not reach significance. Over time, serum Mg levels increased, and erythrocyte Mg levels decreased. C-reactive protein significantly increased in all groups at 4 and 6 weeks but returned to baseline levels by 8 weeks. This study supports the hypothesis that inadequate intake of Mg results in an increase in atherosclerotic plaque development in rabbits. 相似文献
23.
Pulmonary delivery of growth hormone using dry powders and visualization of its local fate in rats. 总被引:9,自引:0,他引:9
A dry powder aerosol formed of human growth hormone (hGH), lactose and dipalmitoylphosphatidylcholine was assessed for systemic delivery of the hormone in rats. The fate of the protein locally in the deep lung was examined post-delivery. The powder was prepared by spray-drying and presented a primary particle diameter of 4.4 microm and a tap density of 0.069 g/cm(3). The mass median aerodynamic diameter was 4.4 micron in the multi-stage liquid impinger at 60 l/min using a Spinhaler device. The emitted dose and fine particle fraction were 89% and 58%, respectively. Varying the airflow rate from 30 to 90 l/min had limited impact on aerosolization properties in vitro. No hGH dimers or glycation adducts were produced during formulation of the powder. hGH absorbed into the bloodstream with a time to peak of 23 and 52 min and with an absolute bioavailability of 23% and 8% following intratracheal insufflation of the dry powder and intratracheal spray-instillation of a solution of the hormone, respectively. Confocal imaging of rat lung revealed an intense uptake of fluorescein isothiocyanate (FITC)-hGH by alveolar macrophages as early as 1 h post-delivery. A dry powder aerosol made of selected GRAS excipients improved absorption of hGH from the lung over a simple solution. 相似文献
24.
Alfred E Buxton Hugh Calkins David J Callans John P DiMarco John D Fisher H Leon Greene David E Haines David L Hayes Paul A Heidenreich John M Miller Athena Poppas Eric N Prystowsky Mark H Schoenfeld Peter J Zimetbaum Paul A Heidenreich David C Goff Frederick L Grover David J Malenka Eric D Peterson Martha J Radford Rita F Redberg 《Journal of the American College of Cardiology》2006,48(11):2360-2396
25.
Carlos Cotrim Otília Sim?es M J Loureiro Pedro Cordeiro Rita Miranda Cecília Silva Teresa Avillez Manuel Carrageta 《Revista portuguesa de cardiologia》2006,25(5):529-533
We describe the case of a pregnant woman with idiopathic pulmonary arterial hypertension, a responder in right heart catheterization, followed since the first trimester in outpatient consultations, admitted to hospital at 23 weeks gestation. She was treated with inhaled iloprost until delivery (at 34 weeks gestation) and continuous infusion of iloprost throughout the perioperative period and following days. This line of therapy has proved efficacious in previous cases. The authors present echocardiographic images that document acute changes in ventricular synchrony during inhalation of iloprost. 相似文献
26.
27.
Andrea DeGaetano William P. Coleman Rita Pizzi Edoardo Tomasella Marco Castagneto Aldo V. Greco 《Journal of clinical monitoring and computing》1994,10(3):147-154
Patient monitoring at the bedside is an inherently parallel job, best handled by multiple individual tasks running concurrently. Cost and diffusion considerations strongly favor the use of PC's at the bedside, but their most widespread operating system, DOS, is not built for multitasking. Hence, a software platform in C language has been prepared, allowing the intermediate programmer to easily write independent modules which will then run simultaneously without conflicts.Such a platform aims at allowing effortless sharing of data among concurrently running processes, while providing strong insulation between tasks, enough to allow multiple copies of any one task to run simultaneously unknown to each other. A cooperative, memory sharing multitasking paradigm has been chosen, which offers fine granularity of timeslicing and low execution overhead at the price of some loss in generality of design.Speed, data exchange capability and number of stackable windows are greater than with commercial packages like Windows or LabWinows. Dynamical reprioritization of tasks is built in, allowing the computerized monitor to focus its attention and resources on urgent tasks. 相似文献
28.
Emilio Bombardieri Antonia Martinetti Rosalba Miceli Luigi Mariani Maria Rita Castellani Ettore Seregni 《European journal of nuclear medicine and molecular imaging》1997,24(11):1349-1355
Bone scintigraphy plays a major role in the diagnosis of bone metastases. The clinical utility of new biochemical markers
of bone metabolism has recently been investigated in various bone diseases. This study evaluated the role of some bone metabolism
markers in comparison with bone scan in the follow-up of breast cancer patients. We studied 149 patients with breast cancer,
33 (22%) of whom had bone metastases. IRMAs were used for the evaluation of blood levels of osteocalcin, bone alkaline phosphatase
(BAP), the C-terminal propeptide of type I procollagen and the C-terminal cross-linked telopeptide of type I collagen (ICTP).
Multivariate regression analysis showed that menopausal status (P=0.007) and metastatic bone lesions (P=0.001) affected bone marker levels. When considering post-menopausal women, the only subset in which bone metabolism marker
behaviour could be reliably investigated, we found a high degree of overlap in marker distribution for scan-positive and scan-negative
patients. Discrimination between scan-negative and scan-positive patients based on the above markers, taken singly or jointly,
was assessed by means of logistic discriminant analysis. The best discrimination was achieved with BAP, closely followed by
ICTP. BAP and ICTP together gave a slight improvement over the use of the two markers separately. However, even in this case
the degree of discrimination was poor and its clinical utility was limited. In fact, to achieve a specificity of 95%, the
sensitivity of the test was about 20%; conversely, with a sensitivity of 95%, the specificity was below 10%. In conclusion,
based on our findings, we believe that blood levels of the investigated markers cannot replace bone scintigraphy in the follow-up
of breast cancer patients for the early detection of bone metastases.
Received 14 April and in revised form 5 July 1997 相似文献
29.
The literature on this rare tumour has been reviewed and three cases of nasal plasmacytoma are described. Immunohistochemistry demonstrated cytoplasmic IgA and Kappa determinants in all cases. Two patients are disease-free at the present time, the third developed an IgG-k multiple myeloma, previously not described in the literature. 相似文献
30.
Alfonso Fasano Antonio E Elia Arianna Guidubaldi Pietro A Tonali Anna Rita Bentivoglio 《Movement disorders》2007,22(4):564-566
We report a case of cervical dystonia occurring in a 33-year-old without personal history of movement disorder but with family history of essential tremor, primigravid, primiparous woman at 1 weeks' amenorrhea, resolved completely after delivery in the course of 3 months. Dystonia never recurred in the following 5 years. Several neurological disorders are known to occur or worsen during pregnancy. As far as we know, this is the second reported case of dystonia occurring during pregnancy, thus confirming that dystonia gravidarum represents a new entity and should be considered in women of reproductive age affected by dystonia, especially when presenting with rapid-onset cervical dystonia. 相似文献