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排序方式: 共有631条查询结果,搜索用时 31 毫秒
121.
VM Reddy DB McElhinney CK Phoon MM Brook FL Hanley 《Canadian Metallurgical Quarterly》1998,115(6):1255-62; discussion 1262-3
BACKGROUND: There is often substantial mismatch between the diameters of the pulmonary and aortic anuli in young patients with systemic outflow tract disease. To implant the autologous pulmonary valve in the aortic position under such circumstances, it is necessary to adapt the geometry of the systemic outflow tract. The effects of such adaptations on autograft function in children are not well known. METHODS: To determine factors predictive of autograft regurgitation, we analyzed 41 cases of children who have undergone the Ross procedure. The diameter of the pulmonary valve was greater (by at least 3 mm) than that of the aortic valve in 20 cases, equal (within 2 mm) in 12 cases, and less (by at least 3 mm) in nine cases, with differences ranging from +10 to -12 mm. In 12 patients with a larger pulmonary anulus, aortoventriculoplasty was used to correct the mismatch. In patients with a larger aortic anulus, the mismatch was corrected by gradual adjustment along the circumference of the autograft, rather than by tailoring of the native aortic anulus. RESULTS: At follow-up (median 31 months), two patients had undergone reoperation on the neoaortic valve for moderate regurgitation. In the remaining 38 cases, autograft regurgitation was as follows: none or trivial in 30, mild in seven, and moderate in one. There was no correlation between regurgitation and age, geometric mismatch, or previous or concurrent procedures. CONCLUSIONS: Subtle technical factors that may result in distortion of the valve complex are probably more important determinants of autograft regurgitation than are indication for repair, geometric mismatch, or previous or concomitant outflow tract procedures. Significant mismatch of the semilunar anuli is not a contraindication to the Ross procedure in children. 相似文献
122.
Roskies Ethel; Seraganian Peter; Oseasohn Robert; Hanley James A.; Collu Robert; Martin N.; Smilga C. 《Canadian Metallurgical Quarterly》1986,5(1):45
Reports a comparison of 3 short-term treatments in modifying behavioral and cardiovascular reactivity to laboratory psychosocial stressors in healthy Type A (coronary-prone) men. 107 men (mean age 37 yrs) completed the treatments and evaluations—33 in aerobic exercise group, and 37 each in cognitive-behavioral stress management and weight-training groups. The stress management group showed significantly greater changes in behavioral reactivity (reductions of 13 to 23% below initial values) than the 2 physical exercise groups, which did not differ significantly from each other. For physiological reactivity, changes attributable to intervention were trivial for all 3 treatment groups. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
123.
K Hanley U Rassner Y Jiang D Vansomphone D Crumrine L Komüves PM Elias KR Feingold ML Williams 《Canadian Metallurgical Quarterly》1996,97(11):2576-2584
Previous studies have shown that ontogeny of the epidermal permeability barrier and lung occur in parallel in the fetal rat, and that pharmacologic agents, such as glucocorticoids and thyroid hormone, accelerate maturation at comparable developmental time points. Gender also influences lung maturation, i.e., males exhibit delayed development. Sex steroid hormones exert opposite effects on lung maturation, with estrogens accelerating and androgens inhibiting. In this study, we demonstrate that cutaneous barrier formation, measured as transepidermal water loss, is delayed in male fetal rats. Administration of estrogen to pregnant mothers accelerates fetal barrier development both morphologically and functionally. Competent barriers also form sooner in skin explants incubated in estrogen-supplemented media in vitro. In contrast, administration of dihydrotestosterone delays barrier formation both in vivo and in vitro. Finally, treatment of pregnant rats with the androgen antagonist flutamide eliminates the gender difference in barrier formation. These studies indicate that (a) estrogen accelerates and testosterone delays cutaneous barrier formation, (b) these hormones exert their effects directly on the skin, and (c) sex differences in rates of barrier development in vivo may be mediated by testosterone. 相似文献
124.
125.
D Tian Z Feng NM Hanley RW Setzer JL Mumford DM DeMarini 《Canadian Metallurgical Quarterly》1998,78(5):568-575
A dispersed, rye-specific element has been used to isolate clones of rye origin from wheat plants containing only a single rye chromosome arm or segment. In this way a set of 23 YAC clones has been isolated from the short arm of rye chromosome 1 (1RS). This technique was extended to isolate clones from a small region of 1RS that contains a large number of agronomically important genes. The targeted cloning method allowed the isolation of 26 classes of lambda clones representing about 5% of the region. Ten of the lambda clones could be mapped to segments within this region. A third example of the application of this technique involved the isolation of clones from a very small but fully functional rye chromosome, the midget chromosome. These clones have allowed the confirmation of the origin of the midget from 1RL, and may provide a tool for the isolation of structural elements of cereal chromosomes. This technique allows the identification of clone libraries for any rye chromosome or chromosome arm, since substitution, addition and translocation lines are available for all rye chromosomes. Furthermore, the technique allows isolation of clones derived from segments of the rye genome recombined into wheat. The method is technically simple and both lambda and YAC libraries can be constructed. Synteny between the genomes of the cereals allows region-specific libraries from rye to be used to target regions of the wheat and barley genomes. 相似文献
126.
BACKGROUND: Nine years ago, a prospective trial began in all U.S. transplant centers to determine whether the results of renal transplantation would improve with the nationwide shipment of kidneys from cadaveric donors to HLA-matched patients. Since then, the stringency of criteria for HLA matching have been liberalized twice, from sharing only those kidneys that matched at all six HLA-A, -B, -DR antigens, to sharing phenotypically HLA-matched kidneys, and most recently to sharing zero HLA-mismatched kidneys. METHODS: Data reported to the United Network for Organ Sharing Scientific Renal Transplant Registry from October 1987 to December 1996 were analyzed to examine the transplant results of nationally shared HLA-matched kidneys and the effects of changes to the HLA matching criteria on graft survival and the distribution of HLA-matched kidneys. RESULTS: The overall 1-year graft survival rate of 5102 HLA-matched transplants was 88% compared with 81% for 58,207 recipients of kidneys with at least one HLA mismatch (P < 0.001). HLA-matched kidneys had a projected 12-year graft half-life, 50% higher than the 8-year half-life of mismatched grafts (P < 0.01). After the first change in the match criteria in August 1990, 1365 phenotypically matched kidneys with fewer than six HLA antigens identified had an 89% 1-year graft survival rate compared with 84% for 466 six antigen-matched kidneys transplanted before the change. After March 1995, 1067 zero HLA-mismatched kidneys that were not phenotypically identical nor six antigen matched, had a 1-year graft survival rate of 88%. Graft survival has not decreased as a result of these changes in the criteria for national sharing, despite an increase in the percentage of matched transplants from 2.5% during the six antigen-match era to 15.5% during the zero antigen-mismatch era. CONCLUSIONS: Changes to the United Network for Organ Sharing policy for national sharing of HLA-matched kidneys have increased the number of patients, and especially minority patients, who can benefit by receiving a well-matched graft without compromising the high graft survival rates provided by an HLA-matched kidney. 相似文献
127.
U Pierre S Wood-Dauphinee N Korner-Bitensky D Gayton J Hanley 《Canadian Metallurgical Quarterly》1998,51(11):983-990
A kappa opioid receptor binding inhibitor was isolated from the fermentation broth of a basidiomycete, Hericium ramosum CL24240 and identified as erinacine E (1). Three analogs of 1 were produced by fermentation in other media and by microbial biotransformation. Of these compounds, 1 was shown to be the most potent binding inhibitor. Preliminary SAR studies of these compounds indicated that all functional groups and side chains were required for the activity. Compound 1 was a highly-selective binding inhibitor for the kappa opioid receptor: 0.8 microM (IC50) for kappa, >200 microM for mu, and >200 microM for delta opioid receptor. Compound 1 suppressed electrically-stimulated twitch responses of rabbit vas deferens with an ED50 of 14 microM. The suppression was recovered by adding a selective kappa opioid receptor antagonist nor-binaltorphimine, indicating that 1 is a kappa opioid receptor agonist. 相似文献
128.
Y. Oshmyansky H. J. M. Hanley J. F. Ely A. J. Kidnay 《International Journal of Thermophysics》1986,7(3):599-608
Experimental measurements are presented for the density and viscosity of selected organic compounds and mixtures at ambient pressure (0.083 MPa) and at temperatures of 298, 318, 338, and 358 K. The compounds studied were decalin, 1-methylnaphthalene, tetralin, m-xylene, tetrahydrofuran, thiophene, quinoline 2,6-lutidine, and m-cresol. Measurements were also made on three mixtures of the compounds decalin, 1-methylnaphthalene, tetralin, m-xylene, and m-cresol. The experimental results are compared with predictions made using a modified corresponding states procedure called TRAPP. The density predictions for the individual compounds and mixtures are good in all cases. For the viscosity, however, the predictions are in reasonable agreement with experiment only for nonassociating compounds and mixtures at reduced densities less than 3. These results suggest that TRAPP may prove very useful as a screening test to distinguish between nonassociating and highly associating mixtures. Such a test would be extremely useful when dealing with mixtures of unknown composition, such as coal liquids.Paper presented at the Ninth Symposium on Thermophysical Properties, June 24–27, 1985, Boulder, Colorado, U.S.A. 相似文献
129.
The authors examined the reliability of facial affect processing deficits found in psychopathic individuals (R. Blair et al., 2004) and whether they could be modified by attentional set. One hundred eleven offenders, classified using the Psychopathy Checklist-Revised (R. Hare, 2003) and Welsh Anxiety Scale (G. Welsh, 1956), performed a facial affect recognition task under 2 conditions. On the basis of research linking psychopathy, amygdala dysfunction, and deficits in facial affect recognition, the authors predicted that psychopathic offenders would display performance deficits when required to identify the emotional expression of particular faces. In addition, given evidence linking the affective processing deficits in psychopathy to focus of attention, the authors predicted that any deficits in facial affect processing would disappear when participants could anticipate which affective cues would be relevant on a given trial. Contrary to expectation, psychopathic offenders performed as well as controls in both conditions. The authors conclude that the conditions that reveal affective deficits in psychopathic individuals require further specification. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
130.
M Juweid RM Sharkey T Behr LC Swayne T Herskovic M Pereira AD Rubin D Hanley R Dunn J Siegel DM Goldenberg 《Canadian Metallurgical Quarterly》1996,37(6):905-911
This study evaluates the pharmacokinetics, dosimetry, toxicity and therapeutic potential of radiolabeled NP-4 and MN-14 anti-CEA antibodies in medullary thyroid cancer (MTC). METHODS: Eighteen patients with advanced MTC entered exploratory clinical studies with therapeutic doses of 131I-labeled NP-4 and MN-14 murine monoclonal antibodies (MAbs) reactive with carcinoembryonic antigen (CEA). Doses administered ranged from 46 mCi for 131I-MN-14 lgG to 195 mCi for 131I-MN-14 F(ab)2 in patients negative for human anti-mouse antibodies (HAMA). RESULTS: The radioconjugate blood half-life (T1/2) for the whole lgG was 42.5+/-5.0 hr compared to 18.8+/- 4.1 hr for the bivalent fragments. Tumor doses of 17.5+/-11.0 and 11.4+/-6.3 cGy/mCi were estimated for 131I-MN-14 lgG and F(ab)2, respectively. Tumor/red marrow dose ratios exceeded 3:1 for most lesions. Red marrow doses of up to 350 cGy generally could be delivered with < grade 4 toxicity. Seven of 14 evaluable patients showed evidence of anti-tumor effects lasting up to 26 months, based on physical exam, tumor markers or computed tomography. CONCLUSION: This study demonstrates that anti-CEA MAbs may be suitable for radioimmunotherapy of metastatic or recurrent MTC. 相似文献