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791.
792.
PB O'Donovan 《Canadian Metallurgical Quarterly》1997,11(9):1387-402; discussion 1402-4
A solitary pulmonary nodule (SPN) is the most common radiographic presentation of lung cancer. The imaging characteristics of solitary pulmonary nodules are described and illustrated. The appearance and implications of extension of lung cancer to the pleura are explored. Finally, the contribution of various thoracic imaging modalities to the diagnosis and staging of lung cancer are discussed briefly. 相似文献
793.
794.
KS Lown RR Mayo AB Leichtman HL Hsiao DK Turgeon P Schmiedlin-Ren MB Brown W Guo SJ Rossi LZ Benet PB Watkins 《Canadian Metallurgical Quarterly》1997,62(3):248-260
Interpatient differences in the oral clearance of cyclosporine (INN, ciclosporin) have been partially attributed to variation in the activity of a single liver enzyme termed CYP3A4. Recently it has been shown that small bowel also contains CYP3A4, as well as P-glycoprotein, a protein able to transport cyclosporine. To assess the importance of these intestinal proteins, the oral pharmacokinetics of cyclosporine were measured in 25 kidney transplant recipients who each had their liver CYP3A4 activity quantitated by the intravenous [14C-N-methyl]-erythromycin breath test and who underwent small bowel biopsy for measurement of CYP3A4 and P-glycoprotein. Forward multiple regression revealed that 56% (i.e., r2 = 0.56) and 17% of the variability in apparent oral clearance [log (dose/area under the curve)] were accounted for by variation in liver CYP3A4 activity (p < 0.0001) and intestinal P-glycoprotein concentration (p = 0.0059), respectively. For peak blood concentration, liver CYP3A4 activity accounted for 32% (p = 0.0002) and P-glycoprotein accounted for an additional 30% (p = 0.0024) of the variability. Intestinal levels of CYP3A4, which varied tenfold, did not appear to influence any cyclosporine pharmacokinetic parameter examined. We conclude that intestinal P-glycoprotein plays a significant role in the first-pass elimination of cyclosporine, presumably by being a rate-limiting step in absorption. Drug interactions with cyclosporine previously ascribed to intestinal CYP3A4 may instead be mediated by interactions with intestinal P-glycoprotein. 相似文献
795.
796.
SM Davies JE Wagner XO Shu BR Blazar E Katsanis PJ Orchard JH Kersey KE Dusenbery DJ Weisdorf PB McGlave NK Ramsay 《Canadian Metallurgical Quarterly》1997,15(2):557-565
PURPOSE: To test the use of unrelated donor bone marrow transplantation (URD BMT) to cure children with high-risk acute leukemias. PATIENTS AND METHODS: Between June 1985 and December 1994, 50 children with acute leukemia (15 acute myelogenous leukemia [AML], 35 acute lymphoblastic leukemia [ALL]; 22 greater than second complete remission [CR]) received BMT from a URD at the University of Minnesota. Ages ranged from 0.9 to 17.5 years (median, 8.8). Median follow-up is 2.1 years (range, 1 to 7.3). Thirty patients (60%) received bone marrow fully matched at HLA-A,B and DRB1; 20 (40%) received bone marrow with a major or minor mismatch at a single HLA-A or B locus. RESULTS: The median time to neutrophil engraftment was day 24 (range, 14 to 42 days) in those receiving matched and day 25 (range, 15 to 32 days) in those receiving mismatched marrow (P = .35). The incidence of grades III to IV graft-versus-host disease (GVHD) was 23% (95% confidence interval [CI], 7% to 39%) in matched and 32% (95% CI, 8% to 52%) in HLA-mismatched patients (P = .57). The incidence of chronic GVHD was 50% (95% CI, 28% to 72%) in matched and 57% (95% CI, 23% to 91%) in mismatched patients (P = .80). Disease-free survival for patients with ALL is 37% (95% CI, 21% to 53%) at 1 year and 30% (95% CI, 15% to 46%) at 2 years; for patients with AML, 53% (95% CI, 28% to 78%) at 1 year and 33% (95% CI, 6% to 60%) at 2 years. CONCLUSION: URD BMT is an effective treatment for children with poor-prognosis acute leukemia and should be considered for all high-risk patients. Early referral of patients is strongly recommended. 相似文献
797.
PB Cserhalmi-Friedman S Karpati A Horvath AM Christiano 《Canadian Metallurgical Quarterly》1997,289(11):640-645
Dystrophic epidermolysis bullosa (DEB) is a genodermatosis characterized by fragility of the skin and mucous membranes. Underlying mutations in the DEB phenotype have been detected in the gene encoding type VII collagen (COL7A1), both in the dominant and recessive forms of DEB. In this study, we searched for mutations in a proband with a mild form of DEB by PCR amplification of segments of COL7A1, followed by heteroduplex analysis. Examination of PCR fragments corresponding to exons 3-4 and exons 51-53 revealed heteroduplexes. Direct sequencing of the PCR fragment containing exon 3 revealed a previously reported A-to-G transition in the 5' donor splice site of exon 3 in the proband and in the clinically unaffected father, while direct sequencing of the PCR fragment containing exon 53 revealed a novel glycine substitution G1652R in the proband and in the clinically unaffected mother. Patients with relatively mild DEB and no family history are frequently diagnosed as a de novo case of dominant DEB, although a mild case of RDEB cannot be excluded on the basis of clinical and ultrastructural examination. We proved this case to be a recessively inherited disease. This information had a profound impact on the genetic counselling, because if the disease of the patient were to have had a new dominant mutation, he would have been counselled that the risk of his offspring being affected was one in two, but he could be accurately counselled that the risk of this offspring being affected was as low as the general population. 相似文献
798.
DS Weigle PB Duell WE Connor RA Steiner MR Soules JL Kuijper 《Canadian Metallurgical Quarterly》1997,82(2):561-565
The factors responsible for the variability in plasma leptin levels observed among individuals with similar body compositions remain unclear. To examine the impact of dietary variables, we compared the changes in leptin levels induced by fasting and dietary fat restriction with the expected decrease following a significant loss in adipose mass. A 21.4 +/- 3.7% weight loss led to a 76.3 +/- 8.1% decrease in mean plasma leptin level (25.2 +/- 9.3 to 6.1 +/- 3.4 ng/mL, P = 0.0001) in a group of 9 obese males. Despite a weight loss of only 2.6 +/- 0.8%, mean plasma leptin levels fell by 61.9 +/- 25.2% (8.5 +/- 4.5 to 2.4 +/- 0.5 ng/mL, P < 0.01) in 7 nonobese females subjected to 3 days of fasting. Leptin levels in fasted subjects returned to baseline within 12 h of refeeding. Individual high- and low-fat meals given to 19 subjects after an overnight fast had no effect on plasma leptin levels. Reduction in dietary fat content from 37-10% of total calories for 7 weeks was also without effect on plasma leptin levels in these subjects. We conclude that plasma leptin levels primarily reflect total adipose mass, rather than meal consumption or dietary energy source, but that the reduction in leptin levels with ongoing fasting is disproportionate to the reduction in adipose mass. The ability of fasting to deactivate this presumed physiological satiety system may have been advantageous in environments characterized by rapid changes in food availability. 相似文献
799.
M Fredholm AK Winter? K Christensen B Kristensen PB Nielsen W Davies A Archibald 《Canadian Metallurgical Quarterly》1993,4(4):187-192
Predation experiments using Gerris (A) spinolae, Laccotrephes griseus and Gambusia affinis were conducted against IV stage culicine larvae with varying prey densities. Ranking of individual predatory efficiency showed the sequence: large Gambusia > medium Gambusia > small Gambusia > female Laccotrephes > male Laccotrephes > Gerris. Predation under coexistence reveals the significance of predatory efficiency of different predator combinations with reference to prey density and exposure period. 相似文献
800.
AL Tardif PB Farrell V Trouern-Trend RH Foote 《Canadian Metallurgical Quarterly》1997,80(8):1606-1612
Computer-assisted sperm analysis equipment was used to evaluate bull sperm initially in a modified Tyrode's solution, in Cornell University extender, and in egg yolk-glycerol-Tris extender (following cooling and storage in the latter two extenders). Two ejaculates of semen were collected from each of eight bulls. Semen was divided into aliquots using a factorial arrangement. The semen, diluted to approximately 20 x 10(6) sperm/ml, was loaded into two 20-micron chambers, and six microscope fields from each chamber were videotaped for each treatment of each ejaculate of semen. Eight sperm characteristics analyzed with the Hamilton Thorne integrated visual optical system (Hamilton Thorne, Beverly, MA) were reported, and some of these characteristics differed significantly among bulls. The initial values of motile sperm in modified Tyrode's solution, Cornell University extender, and egg yolk-glycerol-Tris extender were 87, 79, and 66%; little change followed cooling and storage at 5 degrees C in the latter two extenders. Also, there was a small but significant decline in sperm velocity during 3 d of storage. Hyperactive sperm increased slightly during storage. The procedures used can rapidly and accurately measure many sperm characteristics in fresh semen and in semen stored in egg yolk extenders, and differences among bulls can be detected. 相似文献