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991.
G Benton R C Thomas B G Nickerson J C McQuitty J Okikawa 《American journal of diseases of children (1960)》1989,143(6):678-681
Studies of adults suggest that metered-dose inhalers with spacers are as effective as hand-held nebulizers for bronchodilator delivery. We studied 13 children with acute asthma. They received two puffs every 2 minutes from metered-dose inhalers with spacers (range, 4 to 14 puffs) titrated until improvement stopped. Peak expiratory flow increased 34% for metered-dose inhalers with spacers after the first 2 puffs and increased 87% for metered-dose inhalers with spacers after dose titration. After titration, respiratory rate decreased by 12%, heart rate increased by 2%, and breath sounds improved in 92% of the patients. We concluded that the metered-dose inhalers with spacers are an effective device for the treatment of asthma in the pediatric emergency department and that the use of metered-dose inhalers with spacers with titration can achieve significant bronchodilation in the treatment of patients with acute asthma. 相似文献
992.
Some mutagenic hydrazino compounds are also diamine oxidase inhibitors. Therefore, this interrelationship was studied for the intestinal carcinogen azoxymethane.In vitro, azoxymethane was a very weak inhibitor of rat intestinal diamine oxidase activity.In vivo, after subcutaneous injection of a single dose of azoxymethane, diamine oxidase activity was increased in the duodenum but was mainly inhibited in the colon. Intestinal diamine oxidase activity may then be influenced by regulatory processes induced by azoxymethane rather than by a direct effect.Supported by a grant of the Deutsche Forschungsgemeinschaft Ku 464/2-2. 相似文献
993.
In the present study, we examined the ultrastructure of striatal neurons containing neuropeptide Y (NPY) which were labeled by an immunohistochemical method using peroxidase-conjugated F(ab) fragments in the rat. Each of the 26 neurons identified had a deeply indented oval nucleus. The cytoplasm, which was mainly concentrated at the emergence of the dendrites, contained an abundant Golgi apparatus and a well-developed granular endoplasmic reticulum. Dendrites were poorly branched and rarely exhibited varicosities or dendritic spines. NPY-immunoreactive (Ir) axons were small in diameter and unmyelinated. These features corresponded to a subpopulation of striatal neurons classified as aspiny type IV in previous Golgi studies. Axon terminals forming symmetrical synapses were numerous on the NPY-Ir perikarya and proximal dendrites. On distal NPY-Ir dendrites, synaptic contacts were mainly of the asymmetrical type, suggesting that NPY neurons are contacted by at least 2 categories of afferent fibers. Several NPY-Ir axonal processes and boutons were found to form symmetrical synapses with dendrites, dendritic spines and perikarya belonging to spiny type neurons. These data were consistent with the view that NPY may act as a neurotransmitter of striatal interneurons. Moreover, the frequent observation of NPY axonal processes in the close vicinity of striatal vessels suggested that NPY might also play a role in the control of cerebral vasomotricity. Thirty hours after intranigral injection of 6-hydroxydopamine to induce a degeneration of nigrostriatal dopamine terminals, some characteristic degenerative boutons were observed in close apposition to NPY-Ir cell bodies, suggesting that NPY neurons are under a direct nigrostriatal dopaminergic influence. 相似文献
994.
995.
D J Enscore J L Osborne J E Shaw 《Methods and findings in experimental and clinical pharmacology》1989,11(3):173-178
The in vitro and in vivo functionality of Catapres-TTS, a transdermal therapeutic system that delivers the alpha adrenergic receptor agonist clonidine, is discussed in terms of the drug transport kinetics and resultant plasma drug concentration profiles. The design of Catapres-TTS is presented as an optimization by which the best combination of system performance characteristics is obtained within the inherent limitations of the transdermal drug transport properties and the known pharmacokinetic and pharmacodynamic properties of the drug. Clonidine is a potent antihypertensive agent with a relatively low therapeutic index. For Catapres-TTS, the majority of control over the drug input rate resides within the system, rather than within the skin, which significantly reduces the variability in drug input rate and resulting plasma drug concentration both within and between patients. Moreover, the presence of a rate-control element in the system allows for patterning of the drug release rate. An initial bolus of drug is placed in the contact adhesive layer, where its transport into the skin is not inhibited by the rate control element in the system, for reduction in the time needed to achieve steady state drug input. The selection of the loading dose of drug is described as an optimization between the minimization of the lag time and the maintenance of constant plasma drug concentrations during the crossover period between system applications in chronic therapy. 相似文献
996.
Dermal absorption of the insecticide lindane was determined following topical application of ring 14C-labeled lindane to the tail of Sprague-Dawley rats. The tail was tested as a practical alternative to the rat mid-dorsal (back) region, and the data obtained were compared to those with rat back and with those of rhesus monkeys in our previous reports. There was no significant difference between total percentage urinary 14C recovery for rats dosed on the tail with occlusive tail covers (52 +/- 6.2%; t1/2 = 2.7 d) compared to those with nonocclusive covers (55 +/- 4.4%; t1/2 = 2.9 d). Neither the total percentage urinary recovery nor the t1/2 values obtained for the rat tail and rat back models differed significantly. Carbon-14 activity was still detectable in urine samples taken after 72 d post-treatment. However, an extensive tissue analysis failed to demonstrate 14C activity persisting at 72 d, with the exception of trace levels detected in blood serum and tail tissue. Advantages of the rat tail model are highlighted. 相似文献
997.
P C Kienle 《American journal of hospital pharmacy》1989,46(10):2014-2015
Several methods of collecting workload data for use in PharmaTrend, a computerized pharmacy management information system, are described. Although the number of indicators produced by PharmaTrend is limited by the input of the user, the integrity of the indicators that are produced is not compromised; this allows the user to implement PharmaTrend on a limited scale, such as for workload only. Workload data that can be used in PharmaTrend are collected routinely by most pharmacies. Many activities are already recorded in logs and other noncomputerized sources. The aid of members of the pharmacy department and other departments may be enlisted in collecting these data. Self-reporting through time sheets and cards can also be used to obtain data on the distribution of work hours. Recording is simplified if employees are told to record only exceptions to their usual job responsibilities. The PharmaTrend manual contains detailed definitions of the workload categories, but simpler and more practical definitions may have to be used. A computer spreadsheet program should probably be used for compiling data if they are collected from several sources; this will facilitate entry into PharmaTrend. Simple methods are available for capturing workload data for input into the PharmaTrend program. 相似文献
998.
999.
1000.
In a prospective study 90 patients who had confirmed abruption of the placenta were compared with a control group. Significantly more patients who had abruptio placentae were unmarried, smoked cigarettes, received no antenatal care, had coitus within the 48 hours preceding delivery, developed intrapartum hypertension and had a lower ponderal index than the controls. More patients with abruptio placentae had proteinuria and antepartum hypertension but statistical significance was not reached. In addition, the incidence of intra-uterine growth retardation was higher in these patients. 相似文献