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81.
O Castillo de Febres MD Decker M Estopinan G Bordones KM Edwards 《Canadian Metallurgical Quarterly》1994,13(7):635-639
The safety and immunogenicity of primary immunization at 2, 4 and 6 months of age with Haemophilus influenzae type b capsular polysaccharide conjugated to tetanus toxoid (PRP-T; Act-HIB) were evaluated in infants in Valencia, Venezuela. In order better to assess reactions to PRP-T, subjects received their initial PRP-T vaccine a mean of 6.5 days after their initial diphtheria-tetanus-pertussis (DTP) vaccine. The PRP-T vaccine was well tolerated. Serum was obtained at ages 2 and 7 months (before the first and 1 month after the third PRP-T dose). Antibody responses were compared with those from Nashville infants who had received PRP-T and DTP simultaneously in a previous trial. The preimmunization titers in the Venezuelan and Nashville infants did not differ. The geometric mean postimmunization titer in the Venezuelan infants was 37.9 micrograms/ml, as compared with 3.63 micrograms/ml in the Nashville infants (P < 0.00001). Possible explanations for the exceptional antibody response of these Venezuelan infants to PRP-T include carrier priming caused by prior DTP immunization, synergy associated with the specific DTP vaccine used, preimmunization immunologic experience that differed from their United States counterparts and genetic differences that altered response to the vaccines. Further studies are proposed to evaluate these possibilities. 相似文献
82.
KM Borow A Neumann RM Lang D Ehler B Valentine-Bates A Wolff K Friday M Murphy 《Canadian Metallurgical Quarterly》1993,21(4):939-949
BACKGROUND: Alveolar macrophages from patients with sarcoidosis were analyzed for their ability to secrete tumor necrosis factor-alpha (TNF-alpha), interleukin-1-beta (IL-1-beta), and interleukin-6 (IL-6). RESULTS: Constitutive release of all three monokines in these patients was concomitantly increased in the active state of disease in comparison with inactive sarcoidosis or healthy control subjects. Alveolar macrophages from patients with inactive sarcoidosis compared with cells from healthy subjects showed increased spontaneous secretion of TNF-alpha and IL-6 only, whereas the constitutive release of IL-1-beta was similar as in healthy volunteers. In vitro stimulation of alveolar macrophages from healthy control subjects with lipopolysaccharide or pokeweed mitogen led to a time- and dose-dependent enhanced secretion of TNF-alpha, IL-1-beta, and IL-6. In a similar manner, with corresponding cells from patients with sarcoidosis the secretion of all three cytokines could be further increased by stimulation with lipopolysaccharide or pokeweed mitogen. CONCLUSIONS: The data presented indicate that an increased release of TNF-alpha, IL-1-beta, and IL-6 correlates to disease activity and may play a critical part in the pathogenesis of sarcoidosis. 相似文献
83.
84.
SA Geier E Schielke K Tatsch I Sadri JR Bogner G Hammel KM Einh?upl FD Goebel 《Canadian Metallurgical Quarterly》1993,7(12):1589-1594
OBJECTIVE: The pathogenesis of neurologic and neuropsychologic dysfunction in HIV-1 infection is unclear. The purpose of the study was to determine an association between cerebral perfusion and HIV-1-related ocular microangiopathic syndrome. METHODS: We studied 28 HIV-1-infected patients, seven of whom presented with asymptomatic HIV infection, nine with lymphadenopathy syndrome or AIDS-related complex, and 12 with AIDS. Cerebral perfusion was semi-quantitatively measured by single photon emission computed tomography of the brain using technetium-99 hexamethyl-propylenamine oxime (HMPAO-SPECT). The conjunctival manifestation of HIV-1-related microangiopathic syndrome was measured by a rating scale determining blood-flow sludging and, retinal cotton-wool spots were counted. CD4 count, neopterin, beta 2-microglobulin (beta 2M), haemoglobin, and age were determined as putative confounding variables. RESULTS: Mean conjunctival sludge in patients with normal HMPAO-SPECT findings was 1.3 +/- 0.5 (mean +/- s.e.m.); no cotton-wool spots were present. In patients with slightly impaired HMPAO-SPECT, it was 2.1 +/- 0.6 and mean cotton-wool spot count was 1.1 +/- 0.4. In patients with severely impaired HMPAO-SPECT, mean conjunctival sludge was 4.5 +/- 0.3 and mean cotton-wool spot count was 4.9 +/- 1.1 HMPAO-SPECT findings were closely associated with conjunctival sludge (r = 0.72; P < 0.001) and number of cotton-wool spots (r = 0.78; P < 0.001), whereas only a slight association with staging of HIV disease was found (P = 0.052). Analysis of covariance controlling for CD4 count neopterin, beta 2M, age, and haemoglobin demonstrated a significant difference between the three HMPAO-SPECT groups for both the number of cotton-wool spots (P < 0.001) and the conjunctival sludge rating (P < 0.001). CONCLUSION: There was a close association between severity of HIV-1-related ocular microangiopathic syndrome and severity of cerebral hypoperfusion. Microvascular alterations might contribute to the pathogenesis of neurological and neuropsychological symptoms in patients with HIV-1 disease. Furthermore, the conjunctival sludge rating and the number of cotton-wool spots might be appropriate indicators for severity of microvascular changes of the central nervous system [corrected]. 相似文献
85.
With the advent of distributed and multiple processing systems, the study of interconnection networks has developed into a field of its own. In most cases, the performance measures used to characterize the reliability of such networks have been primitive.It is our purpose, in this brief paper, to survey the many available measures of the vulnerability of interconnection networks. The most widely known is classical connectivity; however, measures more recently introduced in the graph theory literature are probably a better practical metric of reliability. Our objective is to make these measures more widely known, and to spur the development of good algorithms to calculate them in practical instances. 相似文献
86.
87.
Yoo‐Seong Kim Woong‐Sik Kim Hak‐Nyun Choi Tae‐Geum Koh Yong‐Seog Kim 《Journal of the Society for Information Display》2007,15(3):199-204
Abstract— Among various barrier‐rib manufacturing processes, the mold‐pattern‐transfer method has potential to reduce processing cost as well as the manufacture of high‐resolution pixels. In this study, the effects of major processing variables of the mold‐pattern‐transfer process on the formation of air‐trapped pores within barrier ribs were examined. The results indicated that with an optimum combination of the processing variables, barrier ribs without trapped defects can be produced, demonstrating the possibility of reducing the number of processing steps and costs of barrier ribs. 相似文献
88.
KM Peltekian F Wong PP Liu AG Logan M Sherman LM Blendis 《Canadian Metallurgical Quarterly》1997,92(3):394-399
OBJECTIVE: Large volume paracentesis is an effective treatment for refractory ascites, but the need for routine infusion of albumin or other volume expanders remains controversial. The aim of this study was to assess the short term effects of a single 5-L paracentesis without albumin replacement on total central blood volume, systemic and renal hemodynamics, sodium homeostasis, and neurohumoral factors. PATIENTS AND METHODS: Twelve patients with biopsy-proven cirrhosis and tense, diuretic-resistant ascites were studied before and 48 h after a single 5-L paracentesis without albumin infusion. Systemic hemodynamics and total central blood volume were assessed using radionuclide angiography. Glomerular filtration rate and effective renal plasma flow were measured by inulin and para-aminohippurate clearances, respectively. Lithium clearance was used as an index of proximal tubular reabsorption of sodium. In addition, plasma concentrations of neurohumoral factors were determined. RESULTS: Total central blood volume was 2.41 +/- 0.33 L/m2 (mean +/- SEM) before and 2.34 +/- 0.18 L/m2 48 h after large volume paracentesis (p = 0.76). Similarly, no differences were detected in the cardiac index, glomerular filtration rate, effective renal plasma flow, urinary sodium excretion, hematocrit, plasma renin activity, or concentrations of plasma aldosterone, norepinephrine, or atrial natriuretic factor. CONCLUSIONS: A single large volume paracentesis without albumin replacement causes no disturbances in systemic and renal hemodynamics 48 h after the procedure. These results suggest that a single 5-L paracentesis without albumin infusion is a safe and satisfactory short term option for the management of patients with cirrhosis and tense, diuretic-resistant ascites. 相似文献
89.
Unconstrained and constrained motion control of a planar two-link structurally-flexible robotic manipulator are considered in this study. The dynamic model is obtained by using the extended Hamilton's principle and the Galerkin criterion. A method is presented to obtain the linearized equations of motion in Cartesian space for use in designing the control system. The approach to solving the control problem is to use feedforward and feedback control torques. The feedforward torques maneuver the flexible manipulator along a nominal trajectory and the feedback torques minimize any deviations from the nominal trajectory. The feedforward and feedback torques are obtained by solving the inverse dynamics problem for the rigid manipulator and designing linear quadratic Gaussian with loop transfer recovery (LQG/LTR) compensators, respectively. The LQG/LTR design methodology is exploited to design a robust feedback control system that can handle modeling errors and sensor noise, and operate on Cartesian space trajectory errors. Computer simulated results are presented for an example planar, two-link, structurally flexible robotic manipulator. © 1994 John Wiley & Sons, Inc. 相似文献
90.
Ws/Ws rats are deficient in both mucosal- and connective tissue-type mast cells. To study the role of mast cells in active anaphylaxis, changes in vascular permeability in the trachea upon intravenous antigen challenge with Evans blue dye were examined in Ws/Ws, heterogenic Ws/+, and normal +/ + rats sensitized with the nematode Nippostrongylus brasiliensis. Antigen challenge resulted in fatal anaphylactic shock in some +/+ and Ws/+ rats, but not in Ws/Ws rats. Marked dye leakage developed within 30 min in the trachea of +/+ and Ws/+ rats, while Ws/Ws rats showed no substantial increases in the levels of vascular permeability. Ex vivo stimulation of sensitized lung fragments from +/+ animals with specific antigen induced significant releases of histamine and leukotriene (LT) C4, while sensitized Ws/Ws rat-lung fragments did not. In Ws/Ws rats, levels of nematode-specific IgE, IgG1 and IgG2a antibodies as well as levels of lung eosinophilia were not significantly different from those in +/+ rats. These results show that mast cell-deficient Ws/Ws rats fail to develop active anaphylaxis, and this is mediated probably by the lack of mast cell-derived mediators required for initiation of the reaction. 相似文献