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排序方式: 共有1552条查询结果,搜索用时 31 毫秒
971.
A retrospective review of 8 years of treatment in 2 hospitals in Shreveport showed that neoadjuvant chemotherapy with radiotherapy was performed in 39 patients with inoperable, locally advanced head and neck cancer. Twenty-two individuals treated by definitive radiotherapy alone served as historical controls. The cumulative survival rate at 4 years was 34% in patients managed by neoadjuvant chemotherapy with radiotherapy and 7% in patients treated by radiotherapy only. With the exception of greater acute toxicity seen in patients receiving neoadjuvant chemotherapy with radiotherapy, differences in locoregional failure, distant metastasis, and late complication rates were not observed between the patient groups. 相似文献
972.
973.
BC Askew RA Bednar B Bednar DA Claremon JJ Cook CJ McIntyre CA Hunt RJ Gould RJ Lynch JJ Lynch SL Gaul MT Stranieri GR Sitko MA Holahan JD Glass T Hamill LM Gorham T Prueksaritanont JJ Baldwin GD Hartman 《Canadian Metallurgical Quarterly》1997,40(12):1779-1788
The synthesis and pharmacological evaluation of 5 (L-738, 167), a potent, selective non-peptide fibrinogen receptor antagonist is reported. Compound 5 inhibited the aggregation of human gel-filtered platelets with an IC50 value of 8 nM and was found to be > 33000-fold less effective at inhibiting the attachment of human endothelial cells to fibrinogen, fibronectin, and vitronectin than it was at inhibiting platelet aggregation. Ex vivo platelet aggregation was inhibited by > 85% 24 h after the oral administration of 5 to dogs at 100 micrograms/kg. The extended pharmacodynamic profile exhibited by 5 appears to be a consequence of its high-affinity binding to GPIIb/IIIa on circulating platelets and suggests that 5 is suitable for once-a-day dosing. 相似文献
974.
According to Hanss's initial-flow rate method, F. Liao designed a new cell filtrometer in the early 1990s. The parameters, cell initial transit time (Tc) and membrane clogging rate (CR), can be determined by a single measurement with timing accuracy of 1 ms. The new cell filtrometer has two valuable features: a button-pushing operation to control electromagnetic valves; and an autocirculation of fluid in the cell filtrometer resulting in the same volume of leading fluid. A series of comparisons of the new filtrometry with viscometry or ektacytometry shows that the instrument seems to be more sensitive in detecting subpopulations of glutaraldehyde-hardened cells and the shift of deformability for all the cells. The reproducibility of the filtrometer for different membranes made in China and the USA is reasonable (CV < 5% for Tc). Preliminary application of the filtrometer indicates that it might be useful for trial study and routine clinical application. 相似文献
975.
976.
BF O''Hara FL Watson R Andretic SW Wiler KA Young L Bitting HC Heller TS Kilduff 《Canadian Metallurgical Quarterly》1997,48(1):73-86
To identify risk factors associated with an increased risk for ipsilateral breast tumor recurrence following breast-conserving surgery, a cohort of 759 women with T1-T2 tumors were studied. The majority of the patients (88%) had received postoperative radiation therapy to the breast. Median follow-up time was 10 (range: 6-17) years. There was a 1-1.5% yearly increase in ipsilateral breast tumor recurrences. For women < 50 ys the cumulative recurrence rate at 10 years was 18% and for women > or = 50 ys, 9%. Node positive women had a cumulative breast recurrence rate of 25% versus 10% for node negative women. Ten years postoperatively, irradiated patients had a cumulative recurrence rate of 11% versus 26% when no irradiation was given. The beneficial effect of radiotherapy was substantial during the first four postoperative years. The relative risk for an ipsilateral breast tumor recurrence during this period was 4.5 times higher than for non-irradiated patients. However, the protective effect of radiotherapy decreased with time. After ten years the relative risk of ipsilateral breast tumor recurrence was the same among irradiated and non-irradiated patients although the number of events during this period was low. Univariate analysis showed that seven factors were significantly associated with an increased risk of ipsilateral breast tumor recurrence, namely age < 50 ys, increasing tumor size, uncertain microscopic margins, axillary lymph node metastases, no postoperative tamoxifen treatment, premenopausal status, and no postoperative radiotherapy. Three factors remained independently significant after multivariate analysis: age < 50 ys, no postoperative radiation therapy, and positive lymph nodes. In conclusion, radiotherapy reduced the breast recurrence rate, but the effect decreased with time. Node-negative women > or = 50 were a low risk-group for ipsilateral breast tumor recurrence, with a cumulative risk at 10 years of 9% without radiation therapy and 5% with breast irradiation. 相似文献
977.
Armeli Stephen; Eisenberger Robert; Fasolo Peter; Lynch Patrick 《Canadian Metallurgical Quarterly》1998,83(2):288
Police patrol officers were surveyed to investigate how the strength of socioemotional needs affects the relationship between perceived organizational support (POS) and work performance. The association of POS with driving-under-the-influence arrests and speeding citations generally increased with strength of the needs for esteem, affiliation, emotional support, and social approval. Patrol officers with strong socioemotional needs, but not those with weak needs, showed a positive relationship between POS and performance. The findings are consistent with social exchange views that maintain (a) work effort is encouraged by the receipt of socioemotional resources, (b) POS fulfills a variety of socioemotional needs, and (c) the value of POS and the obligation to reciprocate with high performance increase with the strength of socioemotional needs. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
978.
The Development of Comprehension of Main Ideas in Narratives: Evidence From the Selection of Titles.
van den Broek Paul; Lynch Julie S.; Naslund Jan; Ievers-Landis Carolyn E.; Verduin Kees 《Canadian Metallurgical Quarterly》2003,95(4):707
The authors investigated readers' ability to identify main ideas in narrative texts and the development of this ability. In particular, the authors explored students' sensitivity to the goal structure of narratives. Third-, 6th-, 9th-, and 11th-grade students read narratives in which goal statements were systematically varied on 2 structural dimensions: position in the text's hierarchical structure and number of connections to other statements. As a measure of main idea comprehension, students selected titles for the narratives from among the goals or associated outcomes. Hierarchical position, but not number of connections, influenced title choices. Even the youngest students were able to identify the main ideas, but they did so less consistently than did older students. These findings have implications for theories of text comprehension development and for educational practice. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
979.
FL Williams CV Florey SA Ogston NB Patel PW Howie VR Tindall 《Canadian Metallurgical Quarterly》1998,52(8):494-500
GH-releasing peptides (GHRPs) and their non-peptidly mimetics are synthetic molecules which possess marked, dose-related and reproducible GH-releasing effect even after oral administration. Their potent stimulatory effect on GH secretion suggested that GHRP could be useful as provocative test on the diagnosis of GH deficiency. We compared the GH response to the maximal effective dose of Hexarelin (2 micrograms/kg i.v.), an hexapeptide belonging to GHRP family, with that of GHRH (1 microgram/kg i.v.) alone and combined with arginine (ARG, 0.5 g/kg i.v.), which likely acts via inhibition of hypothalamic somatostatin release. We studied 6 prepubertal (4 boys and 2 girls, age 2.6-12.2 yr) and 6 pubertal children with normal short stature (3 boys and 3 girls, age 10.3-14.4 yr) as well as 12 normal young adults (6 males and 6 females, age 22-30 yr) and 12 normal elderly subjects (6 males and 6 females, age 53-79 yr). In prepubertal children, the GH response to HEX (19.0 +/- 4.6 micrograms/l; 611.5 +/- 121.4 micrograms/l/h) was lower than that to GHRH (27.4 +/- 12.7 micrograms/l; 1209.0 +/- 590.9 micrograms/l/h) but this difference did not attain statistical significance. Both these responses were, in turn, lower (p < 0.05) than that to ARG + GHRH (57.9 +/- 15.1 micrograms/l; 2483.6 +/- 696.6 micrograms/l/h). In pubertal children, the GH response to HEX (67.6 +/- 12.7 micrograms/l; 2755.3 +/- 547.3 micrograms/l/h) was higher than that to ARG + GHRH (49.1 +/- 8.9 micrograms/l; 2554.1 +/- 356.6 micrograms/l/h) but this difference did not attain statistical significance; both these responses were, in turn, clearly higher (p < 0.05) than that to GHRH alone (23.1 +/- 7.9 micrograms/l; 1004.8 +/- 214.3 micrograms/l/h). In young adults, the GH response to HEX 60.9 +/- 8.0 micrograms/l; 2401.0 +/- 376.2 micrograms/l/h) was similar to that to ARG + GHRH (68.9 +/- 11.7 micrograms/l; 3035.7 +/- 466.6 micrograms/l/h) and both were clearly higher (p < 0.001) than that to GHRH alone (21.6 +/- 3.6 micrograms/l; 790.0 +/- 137.0 micrograms/l/h). In elderly subjects, the GH response to HEX (22.4 +/- 4.9; 855.0 +/- 199.0 micrograms/l/h) was higher (p < 0.01) than that to GHRH (3.6 +/- 0.8 micrograms/l; 151.8 +/- 24.6 micrograms/l/h) but lower (p < 0.05) than that to ARG + GHRH (48.1 +/- 4.6 micrograms/l; 1758.2 +/- 149.1 micrograms/l/h). In conclusion, GHRPs are a powerful stimulus of GH secretion in pubertal children and young adults only. On the other hand, the age-related variations in the GH response to GHRPs probably limit their reliability for the evaluation of GH releasable pool in prepubertal children and elderly subjects. 相似文献