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121.
Fitzgerald LA Graves MV Li X Hartigan J Pfitzner AJ Hoffart E Van Etten JL 《Virology》2007,362(2):350-361
Acanthocystis turfacea chlorella virus (ATCV-1), a prospective member of the family Phycodnaviridae, genus Chlorovirus, infects a unicellular, eukaryotic, chlorella-like green alga, Chlorella SAG 3.83, that is a symbiont in the heliozoon A. turfacea. The 288,047-bp ATCV-1 genome is the first virus to be sequenced that infects Chlorella SAG 3.83. ATCV-1 contains 329 putative protein-encoding and 11 tRNA-encoding genes. The protein-encoding genes are almost evenly distributed on both strands and intergenic space is minimal. Thirty-four percent of the viral gene products resemble entries in the public databases, including some that are unexpected for a virus. For example, these unique gene products include ribonucleoside-triphosphate reductase, dTDP-d-glucose 4,6 dehydratase, potassium ion transporter, aquaglyceroporin, and mucin-desulfating sulfatase. Comparison of ATCV-1 protein-encoding genes with the prototype chlorella virus PBCV-1 indicates that about 80% of the ATCV-1 genes are present in PBCV-1. 相似文献
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ECG-gated cardiac CT 总被引:12,自引:0,他引:12
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Yakar I Melamed R Shakhar G Shakhar K Rosenne E Abudarham N Page GG Ben-Eliyahu S 《Annals of surgical oncology》2003,10(4):469-479
Background: Prostaglandins (PGs) were shown in vitro to suppress several functions of cellular immunity. It is unclear, however, whether physiological levels of PGs can suppress cellular immunity in vivo and whether such suppression would compromise postoperative host resistance to metastasis.Methods: Fischer 344 rats were administered PGE2 in doses (18 to 300 g/kg subcutaneously) that increased the serum levels approximately 2- to 4-fold. We then assessed the number and activity of circulating natural killer (NK) cells, as well as rats resistance to experimental metastasis of a syngeneic NK-sensitive tumor (MADB106). To study whether endogenously released PGs after surgery compromise these indices, we tested whether laparotomy adversely affects them and whether a cyclooxygenase-synthesis inhibitor, indomethacin (4 mg/kg), attenuates these effects.Results: PGE2 dose-dependently suppressed NK activity per NK cell and dose-dependently increased 4- and 24-hour MADB106 lung tumor retention (LTR); 240 g/kg of PGE2 quadrupled the number of lung metastases counted 3 weeks later. Selective depletion of NK cells abrogated the promotion of LTR by PGE2. Surgery significantly suppressed NK activity and increased MADB106 LTR, and indomethacin halved these effects without affecting nonoperated rats.Conclusions:PGE2 is a potent in vivo suppressor of NK activity, and its postoperative release may promote tumor recurrence. 相似文献
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Anders Broström RN PhD Bengt Fridlund RNT Martin Ulander MD Ola Sunnergren MD Eva Svanborg MD Per Nilsen PhD 《Journal of evaluation in clinical practice》2013,19(1):173-184
Rationale, aims and objectives Continuous positive airway pressure (CPAP) treatment of obstructive sleep apnea (OSA) has a low long‐term adherence. Educational interventions are few and sparsely described regarding content, pedagogical approach and participants' perceptions. The aim was to describe adherence to CPAP treatment, knowledge about OSA/CPAP, as well as OSA patients' perceptions of participating in a group‐based programme using problem‐based learning (PBL) for CPAP initiation. Educational programme The PBL programme incorporated elements from theories and models concerning motivation and habits. Tutorial groups consisting of four to eight patients met at six sessions during 6 months. Methods A sequential explanatory mixed method design was used on 25 strategically selected patients. Quantitative data regarding, clinical variables, OSA severity, CPAP use, and knowledge were collected at baseline, after 2 weeks and 6 months. Qualitative data regarding patients' perceptions of participation were collected after 6 months by semi‐structured interviews using a phenomenographic approach. Results 72% of the patients were adherent to CPAP treatment after 2 weeks and 6 months. All patients improved their baseline knowledge about OSA and CPAP after 2 weeks and sustained it after 6 months. Anxiety and fear, as well as difficulties and needs were motivational factors for participation. Patients described the difficulties of behavioural change, an awareness that improvements do not occur immediately, a realization of the importance of both technical and emotional support and the need for a healthier lifestyle. Conclusion and practice implications A group‐based programme using PBL seems to facilitate adaptive and developmental learning and result in acceptable CPAP adherence levels. 相似文献
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