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751.
Fengguang Zhang Jinrong Qu Hongkai Zhang Hui Liu Jianjun Qin Zhidan Ding Yin Li Jie Ma Zhongxian Zhang Zhaoqi Wang Jianwei Zhang Shouning Zhang Yafeng Dong Robert Grimm Ihab R. Kamel Hailiang Li 《Translational oncology》2017,10(3):324-331
Purpose: To compare the T staging of potentially resectable esophageal cancer using free-breathing radial VIBE (r-VIBE) and breath-hold Cartesian VIBE (C-VIBE), with pathologic confirmation of the T stage. Materials and Methods: Fifty patients with endoscopically proven esophageal cancer and indeterminate T1/T2/T3 stage by CT scan were examined on a 3-T scanner. The MRI protocol included C-VIBE at 150 seconds post–IV contrast, immediately followed by a work-in-progress r-VIBE with identical spatial resolution (1.1 mm × 1.1 mm × 3.0 mm). Two independent readers assigned a T stage on MRI according to the 7th edition of UICC-AJCC TNM Classification, and postoperative pathologic confirmation was considered the gold standard. Interreader agreement was also calculated. Results: The T staging agreement between both VIBE techniques and postoperative pathologic T staging was 52% (26/50) for C-VIBE, 80% (40/50) for r-VIBE for reader 1, and 50% (25/50), 82% (41/50) for reader 2, respectively. For the esophageal cancer with invading lamina propria, muscularis mucosae, or submucosa (T1 stage), r-VIBE achieved 86% (12/14) agreement for both readers 1 and 2. For invasion of muscularis propria (T2 stage), r-VIBE achieved 83% (25/30) for both readers 1 and 2, whereas for the invasion of adventitia (T3 stage), r-VIBE could only achieve agreement in 50% (3/6) and 67% (4/6) for readers 1 and 2, respectively. Conclusion: Contrast-enhanced free-breathing r-VIBE is superior to breath-hold CVIBE in T staging of potentially resectable esophageal cancer, especially for T1 and T2. 相似文献
752.
M. Kamel 《African Journal of Ecology》2008,46(1):96-104
Three species, Zygophyllum album L., Z. coccineum L. and Z. simplex L., from family Zygophyllaceae were collected from two locations in Egypt to study their response to environmental conditions. Organic solutes (amino acids, soluble proteins and soluble sugars) and inorganic solutes (Na+, K+, Ca2+, Mg2+, Cl?, PO43? and SO42?) were estimated to study their role in osmotic adjustment under the effect of drought and salinity. The study showed that Z. coccineum is most tolerant for drought and salinity than Z. simplex. Z. coccineum was dependent on soluble proteins and soluble sugars, to increase its content of bound water, to undergo water deficit in desert. Z. simplex accumulated inorganic solutes more than Z. coccineum and less organic solutes. Amino acids content increased in Z. coccineum and Z. simplex survived in saline conditions to play a role in osmotic adjustment. Under the effect of salinity, all the studied species showed a tendency and high capacity to accumulate inorganic solutes. The main inorganic salutes were Ca2+, Mg2+ and Cl?. The role of Na+ was less than Ca2+ and Mg2+. Z. album and Z. simplex preferred Mg2+ more than Z. coccineum which preferred Ca2+. 相似文献
753.
epi-Androsterone 1 was converted into its hydrazone derivative through the reaction with hydrazine hydrate 80%. Hydrazonoandrostane derivative 2b reacted with hydrazonoyl halides in the presence of K2CO3 forming the corresponding hydrazopyridazinoandrostane derivatives 6a–d. The 3β-acetyl-17-hydrazonoandrostane derivative 2b reacted with a halogen reagent, benzoyl chloride, to form the non-cyclic 16-benzoylated hydrazone 9.On the other hand, compound 2b produced the corresponding pyridazinoandrostane derivatives 11 and 12 via its reaction with phenacyl bromide and chloroacetone respectively. Reaction of the hydrazono derivative 2b with benzaldehyde in the presence of acetic acid drops led to the formation of the benzylidenehydrazonoandrostane derivative 13. The product 14, phosphinom-ethylenehydrazonoandrostane was obtained by the reaction of the derivative 13 with trisdimethylaminophosphine in the presence of dry benzene. The reaction of compound 2b with phenyl isothiocyanate followed by boiling in chloroacetic acid or thioglycolic acid produced the pyrazoloandrostane derivatives 17 and 18 respectively. The biological activity of compounds 6a, 6d, 11, 12, and 15 was evaluated as inhibitor of growth in a human liver carcinoma cell line and doxorubicine was used for comparison. Compounds 15 and 12 showed a higher potency than the other tested compounds. 相似文献
754.
This paper examines the requirements for building database managementsystems and multi-database information resources to supportmolecular biology research. The paper profiles the most importantfeatures of 16 integrated resources and 102 databases relatedto molecular biology research. The aspects surveyed in thispaper include the nature of information in these databases,their sizes, update properties, cross-references, database managementsystem heterogeneity, geographical distribution, data quality,use of temporal information and level of interpretation. Thepaper also comments on the access patterns to these databases.Since not all these aspects were available for all databases,specific comparisons sometimes compare fewer than the full 102databases. Consequently, the same set of databases is not necessarilyalways being compared with respect to every aspect. The paperis organized primarily according to these comparison aspectsand ends with some concluding remarks. 相似文献