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91.
While much time has been spent deliberating about the definition of play, little emphasis has been placed on what children themselves perceive as play. The aim of the present study was to examine social context as a cue for children's perceptions of play and learning. Ninety-two children aged between four and six years (mean four years nine months) participated in the study and completed the Activity Apperception Story Procedure. Children were asked to sort photographic stimuli into those they believed depicted play/not play and learning/not learning. Each of the stimuli were identified by independent raters as containing one of the following social cues; teacher absence (solitary activity, parallel activity or cooperative activity) or teacher presence (teacher involved activity or teacher directed activity). Findings revealed that children associated teacher absence with play. More specifically, children made links between play and the presence of peers (parallel and cooperative activity). Findings are discussed in relation to play in the early years curriculum, differences in children's early educational experiences and the importance of understanding children's perceptions of play. 相似文献
92.
93.
Skoug John W. Borin Marie T. Fleishaker Joseph C. Cooper Anne M. 《Pharmaceutical research》1991,8(12):1482-1488
The mechanism of release from sustained-release adinazolam mesylate tablets was assessed by the Higuchi equation and by analysis of drug release profiles through 60% released using the Peppas equation. Computed values of the diffusional exponent, n, ranged from 0.59 to 0.66. Values of n in this range are consistent with a mixed mechanism of release, with diffusion of drug through the hydrated polymer matrix and relaxation of this matrix being the principal processes controlling release. The rate of in vitro drug release was increased for half tablets relative to whole tablets and is attributed to an increase in the surface to volume ratio of half tablets of about 16%. This increase in surface-to-volume ratio of half tablets was reflected by an increase in the constant, k, from the Peppas equation of 20–23% and by an increase in the slope of Higuchi plots of 12–18% for four lots of tablets. In vivo/in vitro relationships from two bioavailability studies were thoroughly evaluated. Using either a linear or a quadratic relationship, an in vivo/in vitro correlation exists for sustained-release adinazolam mesylate tablets. 相似文献
94.
Jean Marie Jully Marie Christine Béné Gérard Martin Gilbert Faure 《Journal of clinical periodontology》1986,13(3):223-227
The cellular infiltrate present in human diseased gingiva was analyzed in biopsies from 12 patients with gingivitis or periodontitis. The samples studied had been obtained in the course of surgery at inflammatory sites remaining after institution of periodontal treatment. Histological and immunological techniques were used to identify macrophages, B-cells, plasma-cells, T-cells and T cell subsets, as well as cells expressing class II HLA membrane antigens. T-cells appeared as the predominant population, but plasma-cells were also visualized in nearly all samples. Both OKT4+ and OKT8+ cells were seen in all cases, the latter being more numerous in periodontitis patients. Interdigitating-like cells were observed, positively labelled for class II antigens, as well as macrophages which were more numerous in periodontitis patients. These results suggest the participation of all components of the immune response in gingival disease, in a way resembling chronic recurrent inflammatory diseases. 相似文献
95.
Penny H Feldman Christopher M Murtaugh Liliana E Pezzin Margaret V McDonald Timothy R Peng 《Health services research》2005,40(3):865-886
OBJECTIVE: To assess the impact and cost-effectiveness of two information-based provider reminder interventions designed to improve self-care management and outcomes of heart failure (HF) patients. DATA SOURCES/STUDY SETTING: Interview and agency administrative data on 628 home care patients with a primary diagnosis of HF. STUDY DESIGN: Patients were treated by nurses randomly assigned to usual care or one of two intervention groups. The basic intervention was an e-mail to the patient's nurse highlighting six HF-specific clinical recommendations. The augmented intervention supplemented the initial nurse reminder with additional clinician and patient resources. DATA COLLECTION: Patient interviews were conducted 45 days post admission to measure self-management behaviors, HF-specific outcomes (Kansas City Cardiomyopathy Questionnaire-KCCQ), health-related quality of life (EuroQoL), and service use. PRINCIPAL FINDINGS: Both interventions improved the mean KCCQ summary score (15.3 and 12.9 percent, respectively) relative to usual care (p< or =.05). The basic intervention also yielded a higher EuroQoL score relative to usual care (p< or =.05). In addition, the interventions had a positive impact on medication knowledge, diet, and weight monitoring. The basic intervention was more cost-effective than the augmented intervention in improving clinical outcomes. CONCLUSIONS: This study demonstrates the positive impact of targeting evidence-based computer reminders to home health nurses to improve patient self-care behaviors, knowledge, and clinical outcomes. It also advances the field's limited understanding of the cost-effectiveness of selected strategies for translating research into practice. 相似文献
96.
T. Pinzer M. Reiß H. Bourquain K. G. Krishnan G. Schackert 《Acta neurochirurgica》2006,148(10):1085-1090
Summary Aspergillosis belongs to the group of mycotic diseases of paranasal sinuses. The invasive forms, and particularly the fulminant
forms, are potentially fatal. Isolated aspergillosis of the sphenoid sinus or the clivus is a difficult diagnosis, since the
often misleading clinical manifestations of this rare disease develop late. These patients become apparent by neurological
signs such as cavernous sinus syndrome, pseudotumor of the pituitary or the orbit. Diagnosis is often made intra-operatively
or on histological examination.
We report a case of invasive aspergillosis uniquely involving the sellar area revealed by clinical features suggesting a pseudotumor
of the pituitary. Although such lesions are almost always seen in immune suppressed subjects, in our case, the patient was
immune competent and had no past history of sinusitis.
The question of whether, and when to perform limited or extensive surgery remains an issue for discussion, owing to the rarity
of this disease honed by lack of experience. It depends on several factors: the kind of disease, the immunity, the subtype
of invasive fungal sinusitis and the degree of tissue invasion. 相似文献
97.
X Dong M He X Song B Lu Y Yang S Zhang N Zhao L Zhou Y Li X Zhu R Hu 《Diabetic medicine》2007,24(12):1482-1486
AIMS: Our aim was to assess performances of the Cockcroft-Gault and simplified Modification of Diet in Renal Disease (MDRD) formulae in estimating glomerular filtration rate (GFR) in Chinese diabetic populations and their association with vascular risks. METHODS: A total of 1009 patients with Type 2 diabetes were categorized into low estimated GFR groups (GFR < 60 ml/min/1.73 m(2)) and control groups by the two equations. The performances of these formulae were assessed at different stages of kidney function. Carotid artery intima-media thickness (IMT) and the prevalence of diabetic retinopathy or albuminuria were compared among the groups. The ability of these formulae to identify established vascular risk markers using sensitivity, specificity, positive and negative predictive values were also compared. RESULTS: The prevalence of low estimated GFR was 32.7% with the Cockcroft-Gault formula and 5.2% with the MDRD formula, respectively. In low estimated GFR subjects by the MDRD formula, IMT was significantly thicker than those by the Cockcroft-Gault formula (1.2 mm vs. 1.0 mm; P < 0.05), with a higher prevalence of albuminuria (78.4 vs. 52.8%, P < 0.05) and diabetic retinopathy (46.5 vs. 30.5%; P < 0.05). The Cockcroft-Gault formula gave a specificity of 71.7% and a sensitivity of 37.0%, and the MDRD formula gave a specificity of 96.6% and a sensitivity of 7.9% in estimating low GFR relevant for established vascular risks. CONCLUSIONS: These formulae performed differently in Chinese diabetic populations. The simplified MDRD formula is minimally superior to the Cockcroft-Gault formula for its high specificity and positive predictive values in estimating low GFR relevant for vascular risks. 相似文献
98.
目的 初步建立阴道粘膜上皮细胞体外培养方法,为阴道粘膜上皮研究提供实验模型.方法 取雌性新西兰大白兔阴道粘膜组织小块,胶原酶Ⅳ和胰蛋白酶联合消化分离法收集上皮细胞,接种于角朊细胞无血清培养液中静置培养、传代.动态观察细胞生长增殖情况,扫描和透射电镜观察超微结构,流式细胞仪测定细胞增殖周期,并进行免疫组织化学鉴定.结果 体外培养的阴道粘膜上皮细胞为二倍体细胞,增殖状态良好,细胞间可见桥粒连接,免疫组化角蛋白染色阳性.细胞的超微结构和免疫组化染色均具有上皮细胞特征.结论 在本实验条件下,体外培养的阴道粘膜上皮细胞具有较好的增殖能力,可作为阴道粘膜上皮研究的理想实验模型. 相似文献
99.
In vivo Intracellular Recording of Neurons in the Supraoptic Nucleus of the Rat Hypothalamus 总被引:3,自引:0,他引:3
R. E. J. Dyball J-G. Tasker J-P. Wuarin F. E. Dudek 《Journal of neuroendocrinology》1991,3(4):383-386
Intracellular recordings were made from cells in the hypothalamic supraoptic nucleus in the urethane-anaesthetized male rat using the ventral surgical approach. Impalements lasted from 5 min to 1 h and recorded cells had an input resistance of 55 to 170 megohms. Spikes of over 50 mV were recorded from 14 cells which could be antidromically activated by stimulation of the neural stalk. The spikes showed a hyperpolarizing afterpotential and the broadening characteristic of rapidly firing magnocellular neurons, which recovered rapidly (<200 ms). When depolarized, the cells showed evidence of a transient potassium current. Recurrent synaptic coupling between the recorded cell and adjacent cells would be expected to alter the hyperpolarizing afterpotential of an antidromic spike as compared with a spontaneous spike; no perceptible difference in the waveforms of the different types of spike could be detected in 11 spontaneously active cells. Application of just subthreshold stimuli to the neural stalk did not evoke depolarizing or hyperpolarizing potentials. Suprathreshold shocks to the neural stalk, when the antidromic spike was prevented by collision, also had no discernible effect on membrane potential. Thus intracellular recordings from magnocellular neurons in vivo revealed electrophysiological properties similar to those seen in vitro. No evidence for synaptic interconnection between magnocellular neurons was found in male rats. 相似文献
100.
A. Farina 《Journal of pharmaceutical and biomedical analysis》1989,7(12):1579-1583
A simple and rapid fluorimetric method for the determination of 9-fluoro-10-[N-(4′-methyl)piperazinyl]-7-oxo-2,3-dihydro-7H-pyrido[1,2,3-d,e][1–4]benzothyazin-6-carboxylic acid hydrochloride (MF 934), in serum and in pharmaceutical formulations, has been developed based on its strong fluorescence, in 0.1 N H2SO4, at 526 nm (excitation wavelength at 340 nm). The procedure which involves the direct dilution of the sample requires only a few minutes and the sample volume is only 20–100 μl of serum, depending on the drug concentration. Tedious sample preparation procedures such as extraction, deproteinization, or centrifugation are not necessary. The minimum concentration that can be detected is 0.3 ng ml−1, the standard curve in 0.1 N H2SO4 was found to be linear from 0.005 to 1.5 μg ml−1 and from 0.01 to 0.07 g in plasma after dilution with 0.1 N H2SO4. 相似文献