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71.
OBJECTIVE AND DESIGN: Bacterial products as well as the host airway inflammatory responses contribute to the pathogenesis of Pseudomonas infections. We sought to determine if Pseudomonas elastase (PE) induces mitogen-activated protein (MAP) kinase activity in association with interleukin-8 (IL-8) production by alveolar epithelial cells. METHODS: We utilized Western blot analysis to detect phosphorylation of signaling intermediates and ELISA was used to measure IL-8 production. RESULTS: We found that PE induces phosphorylation of the extracellular signal-regulated (ERK1/2) proteins of the MAPK pathway in A549 epithelial cells. Similar results were obtained using primary cultures of rabbit alveolar type II epithelial cells. PE also enhanced IL-8 production, which was abolished in the presence of the ERK activation inhibitor U0126. CONCLUSIONS: We conclude that PE activates the ERK1/2 arm of the MAPK pathway and that activation of this pathway results in enhanced IL-8 production. The results demonstrate that PE may augment pulmonary inflammation via cellular signaling that regulates expression of IL-8.  相似文献   
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73.
Formulae for the calculation of the count of microorganisms isolated from natural bacterial biocenoses of a child's body have been derived. The authors suggest a variant of simplified drip method for the computation of microorganism colonies in solid media. The described method helps cut down the nutrient media consumption at least 3-fold and is time-saving.  相似文献   
74.
The aqueous, organic, and volatile oil extracts of leaves of Eugenia uniflora Linn. Family Myrtaceae were investigated for antibacterial properties using agar dilution techniques. The aqueous extract was the most active against the organisms compared to the organic and volatile oil extracts. The extracts were found to inhibit Gram positive Staphylococcus aureus and Bacillus subtilis and Gram negative Escherichia coli and Shigella dysentcriae. Pseudomonas aeruginosa, Klebsiella pneumoniac, and Salmonella typhi were not inhibited.  相似文献   
75.
The effects of hemorrhagic shock (HE) on duodenal pH, acid-neutralizing capacity and mucosal tolerance to acid were investigated in anesthetized rats, and they were compared with those of indomethacin. HE was performed by bleeding from the carotid artery to reduce arterial blood pressure to about 55 mmHg (3 ml of bleeding per 200 g of body weight), and indomethacin was given s.c. in a dose of 5 mg/kg. Duodenal pH was determined in the outflow from the proximal duodenum (1.7 cm) which was perfused with 10(-4) M HCl, and acid-neutralizing capacity was measured by back-titration of the perfusate to pH 4.0 with 10 mM HCl. Under these conditions, duodenal pH was kept at around 6.0 as the result of neutralization in the loop (approximately 8 microEq/hr). Both HE and indomethacin significantly decreased the pH and acid-neutralizing capacity. Administration of 16,16-dimethyl prostaglandin E2 (16-dmPGE2: 30 micrograms/kg, s.c.) significantly increased both pH and acid-neutralizing capacity in normal and indomethacin-treated rats, but failed to affect these parameters in rats under HE conditions. When the duodenal loop was perfused with 50 mM HCl for 1.5 hr, both HE and indomethacin induced extensive damage in the mucosa. Pretreatment with 16-dmPGE2 significantly reduced the formation of duodenal lesions induced by indomethacin but not by HE. These results suggest that HE as well as indomethacin impaired duodenal acid-neutralizing capacity to reduce the tolerance to acid of the mucosa. The deleterious effects of HE on the mucosa may be mainly due to a decreased mucosal blood flow, but not due to a deficiency of endogenous prostaglandins.  相似文献   
76.
Techniques of ankle arthroscopy   总被引:1,自引:0,他引:1  
Although arthroscopic instrumentation varies widely, the technique for use is quite similar. Surgeon preferences vary but most arthroscopists agree that it is technique that makes the procedure. Discussed in this presentation is the author's method for preparing the patient for arthroscopic surgery, as well as techniques for using the arthroscope, hand instruments, and power instrumentation.  相似文献   
77.
78.
Obese, overweight, desirable, ideal: where to draw the line in 1986?   总被引:1,自引:0,他引:1  
In February 1985, the National Institutes of Health sponsored the Consensus Development Conference on the Health Implications of Obesity. The panel of experts concluded that height and weight tables based on mortality data and the body mass index (BMI) are helpful measures to determine the presence of obesity and the need for treatment. For the dietitian, however, practical concerns arise regarding which index to select. The usefulness of the BMI in patient education and contradictions between the 1959 and 1983 Metropolitan Life Insurance height-weight tables are discussed. A temporary solution is offered in light of the need for further investigation into morbidity experience at weights recommended in the 1983 table.  相似文献   
79.
A novel approach for modelling the biological activity of organic molecules, which requires simultaneous consideration of the influence of all factors (topological, steric, hydrophobic, and electronic) that determine the bioactivity, is used to study the interaction of a series of benzoates with anti-p-(p'-azophenylazo)benzoate antibody. The results obtained suggest that this biological interaction proceeds by a two-step stereospecific mechanism. The first step requires a geometrical correspondence between the benzoates and the cavity in the biomacromolecule, which enables the pharmacophore to come into close contact with the receptor. The second step is the orbitally controlled electronic interaction between the active parts of the benzoates and the antibody. The electronic interaction results from pi-charge transfer from the pharmacophore to the biomacromolecule and from the formation of pi-complexes. A proposed mathematical model for this biological interaction exhibits some statistical advantages over existing models.  相似文献   
80.
Haemophilus influenzae vaccine containing polyribosyl ribitol phosphate (PRP) or PRP covalently linked to diphtheria toxoid (PRP-D) was given to 94 healthy infants 17 to 22 months of age at the same time, but not at the same site, as a diphtheria-tetanus-pertussis booster. Systemic reactions were similar in the two vaccine groups and resembled those expected with the diphtheria-tetanus-pertussis injection alone. Six (13%) and seven (14%) of the PRP and PRP-D recipients, respectively, had minor local reactions to the Haemophilus vaccine. Among the 77 children who were not already naturally immune (ie, anti-PRP antibody concentration of less than or equal to 0.15 micrograms of protein per milliliter) before vaccination, PRP-D was significantly more effective than PRP in inducing protective levels of antibody. Only 15 (43%) of the 35 nonimmune PRP recipients achieved a concentration of greater than or equal to 0.15 microgram/mL and only seven (20%) reached a concentration greater than or equal to 1.0 micrograms/mL following vaccination. In contrast, 34 (81%) of the 42 nonimmune recipients of PRP-D had a concentration of greater than or equal to 0.15 microgram/mL following vaccine and 32 (62%) had a concentration of greater than or equal to 1.0 micrograms/mL (P less than or equal to .001). These results suggest that more than one-half of nonimmune 18-month-old infants will not respond to PRP with protective levels of antibody. In light of the current data, recommendation for revaccination at 24 months of age for those immunized at any younger age is appropriate.  相似文献   
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