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排序方式: 共有643条查询结果,搜索用时 15 毫秒
1.
Mariagrazia Marucci Gert Ragnarsson Anders Axelsson 《Journal of controlled release》2006,114(3):369-380
In this work, Electronic Speckle Pattern Interferometry (ESPI) is presented as a non-invasive tool to study drug transport in controlled release systems. ESPI is shown to be a feasible tool to measure drug film permeability via comparison with an ordinary diaphragm cell. A specially designed cuvette was used in the release study: the polymeric film separated the donor and the receiving chambers of the cuvette to create a diffusion cell with no mixing in the two chambers. Thus, the cuvette mimicked a coated system immersed in a stagnant bulk liquid. Concentration profile data were obtained for the two compartments. Using these data, it was possible to visually discriminate between a film subject only to diffusion and a film subject to diffusion as well as osmotic effects. Moreover, using the concentration profile data collected at different time intervals, it was possible to follow the film properties in terms of drug permeability, thus studying how drug permeability depended on drug concentration. Compared to other measuring techniques, ESPI offers the advantages that no invasive measurements are needed, and that no sampling and calibration are required. Furthermore, the permeability can be measured with no influence of mass transfer in the boundary layers. 相似文献
2.
G Ferrandina G Scambia P Benedetti Panici G Almadori G Paludetti G Cadoni M Distefano M Maurizi S Mancuso 《Cancer letters》1992,67(2-3):133-138
Using an immunoradiometric assay, Cathepsin D (Cath D) levels were measured in the cytosol of 23 normal and 39 neoplastic human laryngeal tissues. Scattered Cath D levels (from 2.2 to 17.8 pM/mg protein; median = 7.6) were found in normal mucosa specimens. Cath D concentrations range from 2.0 to 29.3 pM/mg protein (median = 8.5) in laryngeal tumors. When a comparison between Cath D levels in normal and neoplastic tissue specimens from the same patient was done, Cath D levels were significantly higher in laryngeal cancers than in their normal counterparts (P = 0.03). No correlation with clinico-pathological parameters and steroid hormone and epidermal growth factor receptor status was found. Further studies should investigate whether the production of Cath D by laryngeal tumors could have a clinical relevance for this neoplasia. 相似文献
3.
S M Distefano F Palermo N Crimi A Mistretta F Pamparana A Messa 《International journal of clinical pharmacology research》1988,8(1):31-35
Among the rheological properties of bronchial mucus, "spinnability", i.e. the ability to form threads under the effect of traction, should be regarded as the most closely related to the mucociliary transport function. In the present study the "spinnability" parameter was included in the functional tests aimed at evaluating the efficacy of the carbocysteine-sobrerol combination in 16 patients suffering from chronic abstructive lung disease with bronchial hypersection. Treatment was administered for ten days under double-blind conditions compared with a placebo. The results obtained showed the tested combination to be able to favourably affect all the most important rheological parameters of mucus, including spinnability, leading to a rapid disappearance of signs and symptoms and to the improvement of the most important respiratory function indexes. 相似文献
4.
Protective levels of diphtheria-neutralizing antibody induced in healthy volunteers by unilateral priming-boosting intranasal immunization associated with restricted ipsilateral mucosal secretory immunoglobulin a 总被引:6,自引:0,他引:6
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Mills KH Cosgrove C McNeela EA Sexton A Giemza R Jabbal-Gill I Church A Lin W Illum L Podda A Rappuoli R Pizza M Griffin GE Lewis DJ 《Infection and immunity》2003,71(2):726-732
Subunit intranasal vaccines offer the prospect of inducing combined systemic-mucosal immunity against mucosally transmitted infections such as human immunodeficiency virus. However, although human studies have demonstrated the induction of active immunity, secretory immunoglobulin A (sIgA) responses are variable, and no study has demonstrated protection by accepted vaccine-licensing criteria as measured by direct toxin-neutralizing activity. Using the genetically inactivated mutant diphtheria toxoid CRM(197) in a bioadhesive polycationic polysaccharide chitosan delivery system, we found that a single nasal immunization was well tolerated and boosted antitoxin neutralizing activity in healthy volunteers, which could be further boosted by a second immunization. The neutralizing activity far exceeded accepted protective levels and was equivalent to that induced by standard intramuscular vaccine and significantly greater than intranasal immunization with CRM(197) in the absence of chitosan. A striking but unexpected observation was that although unilateral intranasal immunization induced circulating antitoxin antibody-secreting cells, a nasal antitoxin sIgA response was seen only after the second immunization and only in the vaccinated nostril. If these data are reproduced in larger studies, an intranasal diphtheria vaccine based on CRM(197)-chitosan could be rapidly licensed for human use. However, a restricted sIgA response suggests that care must be taken in the priming-boosting strategy and clinical sampling techniques when evaluating such vaccines for the induction of local mucosal immunity. 相似文献
5.
In an attempt to clarify how cells integrate the signals provided by multiple chemokines expressed during inflammation, we have uncovered a novel mechanism regulating leukocyte trafficking. Our data indicate that the concomitant exposure to CCR4 agonists and CXCL10/IP-10 strongly enhances the chemotactic response of human T lymphocytes. This enhancement is synergistic rather than additive and occurs via CCR4 since it persists after CXCR3 blockade. Besides chemotaxis, other cellular responses are enhanced upon stimulation of CCR4-transfected cells with CCL22/MDC plus CXCL10. Several other chemokines in addition to CXCL10 were able to increase CCL22-mediated chemotaxis. The first beta-strand of the chemokine structure is highly and specifically implicated in this phenomenon, as established using synergy-inducing and non-synergy-inducing chimeric chemokines. As shown in situ for skin from atopic and allergic contact dermatitis patients, this organ becomes the ideal environment in which skin-homing CCR4(+) T lymphocytes can accumulate under the stimulus offered by CCR4 agonists, together with the synergistic chemokines that are concomitantly expressed. Overall, our results indicate that chemokine-induced synergism strengthens leukocyte recruitment towards tissues co-expressing several chemokines. 相似文献
6.
Influence of asthmatic and rhinitic symptomatology duration on bronchial responsiveness to histamine
N Crimi F Palermo R Oliveri C Vancheri S M Distefano B Palermo R Polosa A Mistretta 《International journal of tissue reactions》1987,9(6):515-520
Our Study aimed to investigate the influence of the time in years elapsed from the onset of symptoms on bronchial nonspecific responsiveness in rhinitic and asthmatic patients. The study was performed on 83 asthmatic patients and on 46 patients with allergic rhinopathy. The beginning of the symptoms and years of asthmatic or rhinitic history were particularly investigated. A histamine challenge was performed. The dose of histamine producing at 20% change in FEV1 (forced expiratory volume in one second) was calculated from the individual semilogarithmic dose-response curve (PD20). Bronchial responsiveness to histamine showed wide variability in subjects of two groups, and an overlap of the distribution curves was observed between asthmatic and rhinitic patients. A significant relationship (p less than 0.01) between the years elapsed from the onset of symptoms and bronchial responsiveness to histamine was observed in each group of patients. We noticed that the number of the years passed heightened the bronchial responsiveness to histamine in both groups of patients. 相似文献
7.
Distefano J 《Emergency medical services》1985,14(3):36-7, 39
8.
A F Distefano 《Journal of the American Optometric Association》1976,47(2):216-221
The often proclaimed health care crisis has led to a variety of efforts to reorganize and rationalize the existing health care system. One such effort has been to develop a conceptual model for the delivery of personal health services in which the region is the fundamental planning unit and levels of care form its organizational framework. Three levels of care are defined--primary, secondary, and tertiary--each level being based on a combination of the frequency with which a service is needed and its professional and technical sophistication. The regionalization of health services would serve to "achieve a balance between the public's request for decentralized resources and the centralization required so that they may be used efficiently." 相似文献
9.
G. Distefano M. G. Romeo P. Betta A. Rodono' M. Amato 《European journal of pediatrics》1998,157(4):327-330
A soluble form of thrombomodulin (TM), an anticoagulant proteoglycan of the endothelial cell membrane, considered a marker
of vascular endothelial damage, was measured in plasma of preterm infants with respiratory distress syndrome (RDS). In these
patients, lung immaturity leads to endothelial leak of plasma proteins and to surfactant inhibition. In 18 babies with RDS,
plasma TM concentration was significantly elevated compared with values of a matched group of babies without pulmonary disease
(276.1 ng/ml vs 141.3 ng/ml) (P<0.05). Furthermore, TM levels of mechanical ventilated babies (IPPV) with severe RDS were higher than those of babies with
moderate RDS and treated with nasal CPAP (340.9 ng/ml vs 174.2 ng/ml) (P<0.05).
Conclusion These data show that TM can be used as marker of pulmonary endothelial damage in preterm babies treated with mechanical ventilation
for RDS and suggest early intervention with exogenous surfactant to limit alveolar protein leakage and surfactant inactivation.
Received: 20 February 1997 and in revised form: 7 July 1997 / Accepted: 8 July 1997 相似文献
10.