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41.
Victoria L. Herzberg 《Immunological investigations》1991,20(5):507-513
Serum, which is required for activation of T cells in vitro, was fractionated to isolate and identify major supportive components. The serum activity concentrated exclusively with the lipoprotein fractions LDL and HDL. Furthermore, oleic and linoleic acids were equally active supplements, suggesting that resting T cells may require exogenous lipid because they are incapable of synthesizing fatty acid. A survey of fatty acids disclosed that all were capable of some degree of support. Titration delineated the narrow concentration range of lipid supplements successful in supporting T cell proliferation and demonstrated that concentrations must be rigidly controlled to optimize cell proliferation. 相似文献
42.
J Hernandez-Jaras C Bernis V Paraiso G Barril V Alvarez J A Traver 《American journal of nephrology》1992,12(1-2):105-107
A case of systemic lupus erythematosus (SLE) that developed 2 years after beginning hemodialysis is reported. The patient had not been given any drug implicated in the production of SLE. She had been treated with deferoxamine, an in vitro inhibitory of DNA synthesis. The difficulty of the diagnosis is emphasized. Clinical improvement after prednisone treatment was impressive. SLE may appear even in patients receiving hemodialysis, despite immunological depression derived from chronic uremia. 相似文献
43.
F Ledesma Casta?o S Echevarria Vierna J L Lozano Polo R Oloriz Rivas C Alvarez Moreno F Pons Romero 《European journal of clinical nutrition》1992,46(7):527-533
Interleukin-1 (IL-1) is a cytokine produced by the macrophage-monocyte system that has important effects on immunological responses and inflammatory reactions. Several clinical studies have shown that severe protein energy malnutrition adversely effects cell-mediated immune responses and the functional state of macrophages. The objective of this study was to analyse IL-1 production by adherent cells stimulated in vitro with lipopolysaccharide B (LPS) from patients with alcoholic cirrhosis of the liver and its possible relationship with nutritional states. Forty-five patients with alcoholic cirrhosis and 28 healthy donors were investigated. A combined index of nine anthropometric and biochemical parameters was used to evaluate nutritional status of cirrhotic patients, allowing a distinction to be made between those patients with acceptable nutrition (group I: 40%), those with slight malnutrition (group II: 37.7%), and those with severe malnutrition (group III: 22.3%). IL-1 activity was significantly lower in the cirrhosis patients than in the controls (P less than 0.001). This activity also was significantly lower in samples obtained from cirrhotics with severe malnutrition than in those with acceptable nutrition (P less than 0.05); the combined index and the sole anthropometric index gave the same results, suggesting that malnutrition may play a role in the immunoregulatory disturbances in the pathogenesis of alcoholic liver disease. 相似文献
44.
One of the major difficulties in left heart catheterization through the interatrial septum is to ensure that the Brockenbrough needle tip is correctly laid on the fossa ovalis floor (FOF), which is the only area where the puncture must be done. The difficulties may be enhanced in patients with atrial enlargement and subsequent distortion of the anatomical structures. In order to reduce the hazards of the septal puncture, an electrocardiographic mapping of the right atrial endocardium was performed using the Brockenbrough needle as an exploratory electrode in a group of 20 patients. When the tip of the needle was laid against the FOF, the endoatrial electrocardiogram (EAE) registered a slight or no injury curve, even when the pressure was tight enough to perforate the septum. On the contrary, the pressure on any other area of the muscular septum or atrial walls elicited a bizarre monophasic injury curve. The peculiar electrocardiographic response of the FOF to the pressure exerted by the Brockenbrough needle tip was a valuable aid to identify the area where the transseptal puncture must be done. In addition, the sudden changes in the P wave morphology immediately after the septal perforation, provided the first clue that the left atrium has been reached. 相似文献
45.
Udeni B.R. Balasuriya Jessika C. Dobbe Victoria L. Smalley Eric J. Snijder 《Virology》2004,327(2):318-319
46.
Victoria L Morgan Benoit M Dawant Yong Li David R Pickens 《Computerized medical imaging and graphics》2007,31(6):436-446
The objectives of this study were to use computer-generated phantoms containing real subject motion to: (1) compare the sensitivity of four commonly used fMRI software packages and (2) compare the sensitivity of three statistical analysis strategies with respect to motion correction. The results suggest that all four packages perform similarly in fMRI statistical analysis with SPM2 having slightly higher sensitivity. The most sensitive analysis technique was to perform motion correction and include the realignment parameters as regressors in the general linear model. This approach applies to all four packages examined and can be most beneficial when stimulus-correlated motion is present. 相似文献
47.
The effects of N-n-propylajmaline (prajmalium) on the Na and Ca currents of single frog atrial and ventricular cells were studied by means of the whole-cell patch-clamp technique. Prajmalium (10(-9) to 10(-6) M) depressed the Na current (INa) in a dose- and use-dependent manner. In the same range of concentrations, prajmalium induced a dual effect on the high (ICaL) and low (ICaT) threshold Ca currents (the latter being only present in atrial cells). At a low concentration (10(-9) M), prajmalium increased both Ca currents while at high concentrations (10(-6) M) it depressed them. Prajmalium appeared very potent on ICaT although this current is generally reported to be barely sensitive to agonists and drugs. The action of the drug was also accompanied by a shortening in the half-time of inactivation of the Ca currents and a slight hyperpolarizing shift of their availability curves. The increase in ICaL by prajmalium was not prevented by prazosin (10(-7) M) nor by propranolol (10(-6) M), and it was also observed after ICaL had been fully stimulated by isoproterenol (10(-7)M). Nifedipine (10(-6) M), however, was able to prevent or block the prajmalium-induced increase in ICaL. Some similarities between the actions of prajmalium and dihydropyridine agonists on Ca currents are discussed. 相似文献
48.
M Alvarez R Granados D Mauleón G Rosell M Salas J Sallés N Valls 《Journal of medicinal chemistry》1987,30(7):1186-1193
The synthesis and irreversible alpha-blocking activity in the rat vas deferens of a series of tetra- and diamine disulfides 2-38, structural analogues of benextramine (BHC), are described. All compounds containing a central cystamine moiety displayed an irreversible alpha-adrenergic blockade at concentrations ranging from 10(-4) to 6 X 10(-6)M. Potency was increased in cystamines N,N'-disubstituted with 6-aminohexyl groups, especially when the outer nitrogen atoms bear arylalkyl substituents or are enclosed in a ring. However, N,N,N',N'-tetrasubstituted cystamines were poor blockers. Structural specificity in the outer portion of the tetramine disulfide is low, since many types of substituents gave rise to potent alpha-blockers. Even replacement of the outer amines with nonbasic ethers or amides was observed to maintain irreversible alpha-blockade. 相似文献
49.
Marla E. Salmon Jean Yan Hermi Hewitt Victoria Guisinger 《Health services research》2007,42(3P2):1354-1372
Objective. To (1) provide a contextual analysis of the Caribbean region with respect to forces shaping the current and emerging nursing workforce picture in the region; (2) discuss country-specific case(s) within the Caribbean; and (3) describe the Managed Migration Program as a potential framework for addressing regional and global nurse migration issues.
Principal Findings. The Caribbean is in the midst of a crisis of shortages of nurses with an average vacancy rate of 42 percent. Low pay, poor career prospects, and lack of education opportunities are among the reasons nurses resign. Many of these nurses look outside the region for job opportunities in the United Kingdom, Canada, the United States, and other countries. Compounding the situation is the lack of resources to train nurses to fill the vacancies. The Managed Migration Program of the Caribbean is a multilateral, cross-sector, multi-interventional, long-term strategy for developing and maintaining an adequate supply of nurses for the region.
Conclusions. The Managed Migration Program of the Caribbean has made progress in establishing regional support for addressing the nursing shortage crisis and developing a number of interesting initiatives such as training for export and temporary migration. Recommendations to move the Managed Migration Program of the Caribbean forward focus on advocacy, integration of the program into regional policy decisions, and integration of the program with regional health programming. 相似文献
Principal Findings. The Caribbean is in the midst of a crisis of shortages of nurses with an average vacancy rate of 42 percent. Low pay, poor career prospects, and lack of education opportunities are among the reasons nurses resign. Many of these nurses look outside the region for job opportunities in the United Kingdom, Canada, the United States, and other countries. Compounding the situation is the lack of resources to train nurses to fill the vacancies. The Managed Migration Program of the Caribbean is a multilateral, cross-sector, multi-interventional, long-term strategy for developing and maintaining an adequate supply of nurses for the region.
Conclusions. The Managed Migration Program of the Caribbean has made progress in establishing regional support for addressing the nursing shortage crisis and developing a number of interesting initiatives such as training for export and temporary migration. Recommendations to move the Managed Migration Program of the Caribbean forward focus on advocacy, integration of the program into regional policy decisions, and integration of the program with regional health programming. 相似文献
50.