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51.
RNase H1 from Escherichia coli cleaves single strand RNA extending 3' from an RNA-DNA duplex. Substrates consisting of a 25-mer RNA annealed to complementary DNA ranging in length from 9-17 nucleotides were designed to create overhanging single strand RNA regions extending 5' and 3' from the RNA-DNA duplex. Digestion of single strand RNA was observed exclusively within the 3' overhang region and not the 5' overhang region. RNase H digestion of the 3' overhang region resulted in digestion products with 5'-phosphate and 3'-hydroxyl termini. The number of single strand RNA residues cleaved by RNase H is influenced by the sequence of the single strand RNA immediately adjacent to the RNA-DNA duplex and appears to be a function of the stacking properties of the RNA residues adjacent to the RNA-DNA duplex. RNase H digestion of the 3' overhang region was not observed for a substrate that contained a 2'-methoxy antisense strand. The introduction of 3 deoxynucleotides at the 5' terminus of the 2'-methoxy antisense oligonucleotide resulted in cleavage. These results offer additional insights into the binding directionality of RNase H with respect to the heteroduplex substrate. 相似文献
52.
This paper is one of three in a series prepared by the Research, Science and Therapy Committee of The American Academy of Periodontology and is intended for the information of the dental profession. It represents the position of the Academy regarding the current state of knowledge about treatment of gingivitis and periodontitis. The other papers are entitled The Etiology and Pathogenesis of Periodontal Diseases and Diagnosis of Periodontal Diseases. 相似文献
53.
JH Pruett KB Temeyer WF Fisher PK Beetham SE Kunz 《Canadian Metallurgical Quarterly》1998,35(5):861-871
In this study potential vaccine candidate immunogens were identified and evaluated in a vaccine challenge trial. Calves vaccinated with a partially purified fraction of Psoroptes ovis-soluble proteins had 8 of 14 calves free of palpable lesions 8 wk after a challenge infestation. A self-grooming behavioral response elicited by a pruritic immediate-type allergic reaction was believed to be an effector in protecting the vaccinated calves from a clinical P. ovis infestation. 相似文献
54.
Lipoprotein lipase (LPL) hydrolyses triglycerides in chylomicrons and in very low density lipoproteins. In this study, a new sensitive enzyme immunoassay, the dissociation-enhanced lanthanide fluorescence immunoassay (DELFIA), for the quantification of immunoreactive LPL mass in biological specimens was developed. In the indirect sandwich DELFIA assay polyclonal anti-human or anti-bovine LPL IgGs were used as capture antibodies, monoclonal antibody (mAb) 5D2 and Eu(3+)-labelled goat anti-mouse IgG were used as detection antibodies. In the direct sandwich DELFIA assay, mAb 5D2 was used as capture and Eu(3+)-labelled mAb 5D2 as detection antibodies. Both purified bovine and human LPL proteins served as standards in the indirect and the direct DELFIA assay. Standard curves were linear between 0.1 and 1000 ng LPL/ml, assuring the sensitivity of the DELFIAs within this range. Mean values for immunoreactive LPL mass in normal individuals were found to be 40.3 +/- 14.4 ng/ml preheparin plasma and 334.1 +/- 71 ng/ml postheparin plasma. In patients affected with type I hyperlipoproteinemia 82.4 +/- 29.3 ng/ml (postheparin plasma) were determined. Coefficients of inter- and intra-assay variation were 4.3% and 6.2% on average. The correlation coefficient between the indirect and the direct DELFIA technique was 0.9694. The correlation coefficient between immunoreactive LPL mass (estimated by DELFIA) and LPL activity (estimated by the LPL activity assay) was 0.9345. Our data are consistent with the concept that LPL is active as a dimer. Dissociation of the LPL dimer into monomers is tightly coupled to both loss of immunoreactivity and enzyme activity of LPL. 相似文献
55.
A 39-year-old woman presented with acute myocardial infarction due to spontaneous dissection of the left anterior descending artery. This was treated conservatively. She had been on combined oral contraceptive pills from the age of 22. Repeat coronary angiography 7 months later revealed spontaneous complete healing. 相似文献
56.
57.
P Diemunsch A D'Hollander L Paxton P Schoeffler P Wessel S Navé RA Brown WF Hahne 《Canadian Metallurgical Quarterly》1997,9(5):365-373
STUDY OBJECTIVE: To evaluate a range of doses of intravenous (i.v.) dolasetron mesilate, in preventing postoperative nausea and vomiting (PONV). DESIGN: Double-blind, placebo-controlled, randomized, multicenter trial. SETTING: Ten hospitals and/or surgical centers. PATIENTS: 281 women undergoing gynecologic surgery with general anesthesia. INTERVENTIONS: Patients received one of four single, i.v. doses of dolasetron mesilate (12.5 mg, 25 mg, 50 mg, and 100 mg) or placebo administered following cessation of anesthesia. MEASUREMENTS AND MAIN RESULTS: Patients were monitored for 24 hours following study drug administration. The antiemetic efficacy of each dolasetron mesilate dose was evaluated by recording the number and timing of emetic episodes, and the effects on nausea were assessed by use of visual analog scales (VAS). Safety was assessed by adverse event reports, clinical laboratory tests, electrocardiographic (ECG) measurements, and monitoring vital signs. Complete responses (patients with no emetic episodes and no escape antiemetic medication requirements in 24 hours) were achieved by 54% in the 12.5-mg, 67% in the 25-mg, and 59% in both the 50-mg and 100-mg dolasetron mesilate dose groups, and by 43% in the placebo group. Nausea VAS assessments demonstrated that dolasetron-treated patients were significantly (p = 0.048) more likely to report no nausea (VAS score < 5 mm) than those in the placebo group. Adverse events reported generally were mild in intensity, and there were no clinically significant changes in laboratory tests, vital signs, or ECG parameters. CONCLUSIONS: Dolasetron was effective and well tolerated for the prevention of PONV in female patients undergoing gynecologic surgery with general anesthesia. 相似文献
58.
59.
WF Mahaffee EM Bauske JW van Vuurde JM van der Wolf M van den Brink JW Kloepper 《Canadian Metallurgical Quarterly》1997,63(4):1617-1622
Field releases of the wild-type plant growth-promoting rhizobacterium Pseudomonas fluorescens 89B-27, its bioluminescent derivative GEM-8 (89B-27::Tn4431), and a spontaneous rifampin-resistant variant estimating the wild-type population. Seed and root samples were taken 0, 7, 14, 21, or 28, 35 or 42, and 70 days after planting in each year and processed for enumeration by spiral plating or immunofluorescent colony staining (IFC). In both years, the populations of 89B-27, R34, and GEM-8, as measured by IFC, were not significantly different (P > 0.05) from each other at each sampling time. However, the populations of R34 and GEM-8, as measured by spiral plating and differentiation based on their respective phenotypes, were significantly lower (P < 0.05) than the wild-type populations and their IFC-determined populations. These data indicate that traditional marker systems may underestimate populations and hence the survival and colonization of genetically marked bacteria. 相似文献
60.
EB Rubenstein RJ Gralla JD Hainsworth PJ Hesketh TH Grote MR Modiano A Khojasteh LA Kalman CR Benedict WF Hahne 《Canadian Metallurgical Quarterly》1997,79(6):1216-1224
BACKGROUND: This double blind parallel group study assessed the acute antiemetic efficacy of four oral doses of dolasetron mesylate in cancer patients receiving their first course of intravenous chemotherapy with doxorubicin and/or cyclophosphamide. METHODS: Patients were randomized to receive 25, 50, 100, or 200 mg of dolasetron mesylate 30 minutes prior to chemotherapy and were monitored for nausea and emetic episodes for the next 24 hours. RESULTS: Three hundred and nineteen cancer patients at 32 sites completed the study. Most patients were female (81%); of this group, 69% had breast carcinoma. A highly statistically significant linear trend demonstrating improved response with higher doses was detected for complete response (no emetic episodes and no rescue medication) (P < 0.001), for complete plus major response (0-2 emetic episodes and no rescue medication) (P < 0.001), and for patient visual analog scale assessments of nausea (P = 0.001) and general satisfaction with antiemetic therapy (P = 0.001). No serious adverse events were noted. The most frequent adverse event was mild, self-limiting headache, which has been reported with other drugs in this class. CONCLUSIONS: Single oral doses of dolasetron mesylate were found to be effective in preventing acute emesis in cancer patients receiving moderately emetogenic chemotherapy. 相似文献