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The mutational specificity of the syn dihydrodiol epoxide of 5-methylchrysene in the supF gene of the pSP189 vector was examined. Transversion mutations at GC pairs predominated with G → T and G → C changes accounting for 42 and 21% of total base change mutations. The types of mutations found reflect the previously determined chemical preference of this reactive species for reaction with deoxyguanosine residues in DNA. 相似文献
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Characterization of adenosine receptors involved in adenosine-induced bronchoconstriction in allergic rabbits. 总被引:2,自引:0,他引:2 下载免费PDF全文
A. el-Hashim B. D'Agostino M. G. Matera C. Page 《British journal of pharmacology》1996,119(6):1262-1268
1. Recent work has suggested that adenosine may be involved in asthma via the activation of A1 receptors. However, the role of the recently cloned A3 receptor in airways is largely unknown. In the present study, we have investigated the role of the A3 receptor in adenosine-induced bronchoconstriction in allergic rabbits. 2. Aerosol challenge of antigen (Ag) immunized rabbits with the adenosine precursor, adenosine 5'-monophosphate (AMP), resulted in a dose-dependent fall in dynamic compliance (Cdyn). The maximum fall in Cdyn in these rabbits was significantly greater than that in litter matched, sham immunized animals (P < 0.05). However, there was no significant difference in the maximum increase in airways resistance (Rt) between Ag and sham immunized rabbits (P > 0.05). 3. Aerosol challenge of Ag immunized rabbits with cyclopentyl-adenosine (CPA) (A1-receptor agonist) elicited a dose-dependent fall in Cdyn in Ag immunized rabbits and the maximum fall in Cdyn in these rabbits was significantly greater than that observed in sham immunized rabbits (P < 0.05). Similarly, CPA induced dose-dependent increases in R1 in Ag immunized rabbits whereas sham immunized rabbits failed to respond to CPA within the same dose range. The maximum increase in RL in Ag immunized rabbits was significantly greater than that of sham immunized rabbits (P < 0.05). 4. Aerosol challenge of either Ag or sham immunized rabbits with the A3 agonist aminophenylethyladenosine (APNEA) did not elicit dose-dependent changes in either RL or Cdyn. Moreover, there was no significant difference in the maximum response, measured by either parameter, between the two animal groups (P > 0.05). 5. These data provide further evidence for a role of the A1 receptor in the airways, but do not support a role for the A3 receptor in adenosine-induced bronchoconstriction in the allergic rabbit. 相似文献
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Doug Joshua Max Wolf Jane Matthews Lee Tan William Sheridan Glenn Pilkingtonh Fiona Page 《Leukemia & lymphoma》1994,14(3):303-309
The Australian Leukaemia Study Group myeloma study (MM1) aimed to determine the prognostic significance of clinical and immunophenotypic markers in patients with multiple myeloma. All patients were treated with standard dose melphalan and prednisone. Seventy-four patients were entered and the median survival was 27 months. Serum beta 2-microglobulin (βM) and albumin levels were the only significant clinical factors influencing survival (p = 0.007 and p = 0.008, respectively). Patients with raised levels of CD38+ lymphocytes at presentation had a significantly shorter survival than patients with normal levels (p = 0.01, logrank test, median 19 months vs 33 months). CD38 antigen expression was independent of β2M but patients with raised levels of CD38 had significantly lower levels of albumin than patients with normal levels (p = 0.001) which may explain their poorer survival. Salmon and Durie stage was not associated with antigen expression. No other B-cell antigens (CD10, CD19, CD20, CD21, CD22, CD23, FMC1 or FMC7) or plasma cell antigens tested (PCA-1) were found to be associated with prognosis. Patients who achieved plateau phase had a better prognosis than those who did not (p = 0.04 in a landmark analysis). Patients who achieved plateau phase following an objective response appeared to have a better prognosis than those who were in plateau phase at presentation (p = 0.09 in a landmark analysis). Light chain isotype suppression (LCIS) was not associated with a significant survival advantage and did not correlate with any known prognostic indicator. We conclude that phenotypic analysis of peripheral blood lymphocytes for CD38 antigen at diagnosis may be useful as a prognostic indicator in patients with myeloma. 相似文献
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G G Page 《Heart & lung : the journal of critical care》1986,15(4):390-401
This article has discussed TOF, its occurrence, physiology, medical interventions and nursing implications. In its classic form, TOF consists of four anatomical aberrations: a large VSD, pulmonic stenosis, dextroposition of the aorta, and right ventricular hypertrophy. Surgical palliation versus primary intracardiac repair is a continuing discussion in medical literature. Children who have undergone intracardiac repair for TOF have an excellent prognosis for late survival, near 90% 10 years after repair. Nursing responsibilities in the care of the newborn diagnosed as having TOF encompass the well-being of the newborn as well as the family. Palliation increases pulmonary arterial flow, thus decreasing cyanosis and promoting measurable clinical improvement in the infant. Preparation of the family and child for surgery involves completing a baseline assessment of family dynamics, diagnosing stressors, composing objectives, carrying out interventions focused on developmental ability, and evaluating the effectiveness of the nursing process. Maintaining the physical and emotional integrity of a child just out of the operating room is a challenge. Parental support is important to the young child's feelings of security while hospitalized. 相似文献
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The questioning skills of nursing instructors 总被引:1,自引:0,他引:1
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In vivo transfer and expression of a human epidermal growth factor gene accelerates wound repair. 总被引:18,自引:0,他引:18 下载免费PDF全文
C Andree W F Swain C P Page M D Macklin J Slama D Hatzis E Eriksson 《Proceedings of the National Academy of Sciences of the United States of America》1994,91(25):12188-12192
This report details the transfer of a human epidermal growth factor (hEGF) expression plasmid to porcine partial-thickness wound keratinocytes by particle-mediated DNA transfer (Accell). After gene transfer an external sealed fluid-filled wound chamber was used to protect the wound, provide containment of the exogenous DNA and expressed peptide, and permit sampling of the wound fluid. Analysis of wound fluid for hEGF and total protein, an indicator of reformation of the epithelial barrier, showed that wounds bombarded with the hEGF plasmid exhibited a 190-fold increase in EGF concentration and healed 20% (2.1 days) earlier than the controls. EGF concentrations in wound fluid persisted over the entire 10-day monitored period, decreasing from 200 pg/ml to 25 pg/ml over the first 5 days. Polymerase chain reaction results showed that plasmid DNA was present in the wound for at least 30 days. These findings demonstrate the possible utility of in vivo gene transfer to enhance epidermal repair. 相似文献
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