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991.
To evaluate sites of enterovirus replication and to characterize the resulting lesions, twenty 4-day-old specific-pathogen-free (SPF) turkey poults were orally inoculated with an enterovirus. Twenty uninoculated SPF poults served as controls. Inoculated poults were depressed, had ruffled feathers, watery droppings, and pasted vents. Gross lesions were dilated thin-walled ceca with foamy yellow fluid. Immune electron microscopy of the gastrointestinal tract contents revealed an enterovirus with an average diameter of 23.5 nm. Immunoperoxidase and indirect immunofluorescent antibody assays revealed intracytoplasmic staining in enterocytes of the duodenum, jejunum, and ileum. This correlated with the scanning electron microscopy findings, which showed the most lesions in the jejunum and ileum. The ileum had prominent cell outlines because of rounded, distinct, bulging epithelial cells. Histopathology revealed slight shortening of villi and increased crypt depth in the intestines of inoculated poults. Our findings indicate that the small intestine is the site of turkey enterovirus replication, and the gross and microscopic changes observed are determined to result from viral damage to the enterocytes. 相似文献
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993.
In this paper the design and application of a voltage regulator for use in Photovoltaic Systems with two separate loads of different priority is presented. The Single-Stage Dual Priority Regulator (SSDPR) charges two separate battery systems for high and low priority loads. The controller always charges the main battery first. It toggles between the two batteries when the main battery is nearly charged, and reduces the charge duty cycle of the main battery as it approaches full charge. The SSDPR utilizes the PV more efficiently by supplying low priority loads without jeopardizing the reliability of the critical load. Both the main and auxiliary voltage settings are adjustable, allowing the use of different types of batteries. The SSDPR is being tested in the University of Lowell Vaccine Refrigerator Laboratory. A dual priority regulator is useful in any stand-alone system with multiple loads. Uses include photovoltaic powered homes, medical clinics, and recreational vehicles. 相似文献
994.
RS Spielman RE McGinnis WJ Ewens 《Canadian Metallurgical Quarterly》1994,54(3):559-60; author reply 560-3
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OBJECTIVE: To compare efficacy and tolerance of recombinant interferon alfa-2b in the treatment of anti-HCV-positive chronic active hepatitis (CAH) in subjects aged 65 years and above with those less than 65. DESIGN: A randomized controlled trial. SETTING: Outpatients in two hospitals. PATIENTS: 65 consecutive outpatients with anti-HCV-positive CAH for 1 to 30 years, having basal aminotransferase levels at least twice the normal value. Those 65 and over were randomized to an interferon group (A, n = 22) or a no-treatment group (B, n = 22). All those under 65 received interferon (group C, n = 21). INTERVENTION: Interferon at a dose of 3 mU 3 times a week for a 6-month period. A normalization of serum aminotransferase levels was considered a positive response to therapy. RESULTS: Response to therapy was positive in 62% of the treated elderly compared to 57% of the adults (P = 0.85). The two groups of responders showed a common highly significant reduction of aminotransferase (P < 0.001). Side effects were similar in elderly and young. Two untreated elderly showed spontaneous normalization of aminotransferase. CONCLUSION: Interferon in anti-HCV-positive CAH is useful in the elderly, allowing normalization of aminotransferase, improvement of the histology and remission of the disease in 62% of the cases. Side effects seem to be independent of age. Further studies are required to assess both duration of remission and usefulness of cyclic therapy in previous responders. 相似文献
998.
S Bank M Blumstein RE Greenberg D Magier PT Lavin 《Canadian Metallurgical Quarterly》1993,15(1):36-45
Seventy-one of 85 consecutive patients with endoscopically confirmed active benign gastric ulcers completed an 8-week study to evaluate the effects on healing of famotidine 40 mg given as a single dose at night. The healing rate in the 48 patients in whom the ulcers were associated with nonsteroidal anti-inflammatory drug (NSAID) or aspirin (ASA) use was compared with that in the 23 patients with idiopathic ulcers. Endoscopy, symptom assessments, antacid use, hematology, and serum chemistry were performed at weeks 4 and 8 of treatment. Famotidine 40 mg at bedtime healed 63 (89%) of the 71 ulcers at 8 weeks; the healing rate for NSAID/ASA-associated ulcers was 46 (96%) of 48, which was significantly greater than that for idiopathic ulcers (17 of 23; 74%) (P = 0.0119). Of the 54 patients who returned a questionnaire 1 to 2 years after completing the study, 20% were still taking an NSAID/ASA (mainly for cardiovascular prophylaxis). About half of the patients surveyed were taking anti-ulcer medication. None of these patients had experienced any serious ulcer complication. The results of this study suggest that differentiating NSAID/ASA-induced ulcers from idiopathic ulcers may be important with regard to healing rates and duration of therapy. 相似文献
999.
ML Weisfeldt RE Kerber RP McGoldrick AJ Moss G Nichol JP Ornato DG Palmer B Riegel SC Smith 《Canadian Metallurgical Quarterly》1996,32(2):127-138
Experimental conditions (pH 6.5, 24 h reaction, peptide:biotin ratio 1:5) were defined for preferential incorporation of the biotin molecule in the N-terminal alpha-amino group of peptides. This strategy could be helpful in numerous applications when an entire peptide chain must remain accessible for antibody or receptor binding. We illustrate this advantage in a solid-phase enzyme immunoassay designed to detect antibodies specific for bovine beta-lactoglobulin present in rabbit or human sera. This test involves synthetic peptides biotinylated in different positions and immobilized on a solid phase. The use of biotin/streptavidin interactions permitted more efficient detection of specific anti-peptide antibodies than solid phases prepared using conventional passive-adsorption techniques. The highest levels of antibody binding were measured when biotinylation occurred at the N-terminal extremity of immobilized peptides. 相似文献
1000.