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41.
The aim of this study was to assess alcoholic inpatients' smoking and coffee intake variation following withdrawal. Only moderate smokers (less than 30 cigarettes/day) showed a significant increase of cigarette consumption after alcohol withdrawal. However, their urinary cotinine level did not vary, suggesting a behavioral, and not biological, compensation through smoking following alcohol withdrawal. Heavy smokers (30 cigarettes/day or more) showed no significant clinical or biological variation of smoking behavior. Coffee consumption increased after alcohol withdrawal in all patients, irrespective of smoking habits.  相似文献   
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Regional binding of 123I-iododexetimide, a muscarinic acetylchline receptor antagonist, was measured in vivo in the temporal lobes of 4 patients with complex partial seizures using single-photon emissions computed tomography. In the anterior hippocampus ipsilateral to the electrical focus, 123I-iododexetimide binding was decreased by 40 ± 9% (mean 7plusmn; SD, p <0.01) compared with the contralateral hippocampus; 123I-iododexetimide binding in other temporal lobe regions was symmetrical. The data indicate a regionally specific change of muscarinic acetylcholine receptor in anterior hippocampus in complex partial seizures of temporal lobe origin.  相似文献   
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自中药槲寄生中分离得到一个新的黄酮甙,经波谱测定及水解试验,确定其结构为鼠李秦素-3-O-β-D-芹糖基(1→2)-[6″-(3-羟基-3-甲基戊二酸半酯)]葡萄糖甙,命名为槲寄生新甙Ⅶ(viscumneoside Ⅶ).  相似文献   
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BACKGROUND: The phenomenon of wound contraction results in a decrease in wound size and a healed scar significantly smaller than the original defect. OBJECTIVE: This study was undertaken (1) to determine the amount of wound contraction in Mohs surgery defects allowed to heal by second intention, (2) to evaluate for regional differences in wound contraction based on the facial anatomic zones for second intention healing described by Zitelli, and (3) to determine whether regional differences in wound contraction account for observed differences in cosmetic outcome. METHODS: One hundred sixty secondarily healed Mohs surgery defects limited to the head and neck having a wound age of greater than 12 weeks in 102 consecutively examined patients were carefully measured with a tissue caliper. The percent wound contraction was calculated and compared for each Zitelli anatomic subunit. The final shape of the wound (quantitatively described) and the cosmetic acceptability (subjectively rated by the patient and examiner) were also compared with the percent wound contraction for each anatomic area. RESULTS: Both NEET (concave surface of the nose, eye, ear, and temple) and FAIR (forehead, antihelix, eyelids, and the remainder of the nose, lips, and cheeks) areas were identical in terms of mean wound contraction (74%), cosmetic acceptability (97%), and conversion to a wound shape with a ratio of maximal length to width of greater than 3.0 (fusiform and linear shapes) (52%). NOCH areas (convex surface of the nose, oral lips, cheeks and chin, and the helix of the ear) demonstrated less wound contraction (66%), cosmetic acceptability (78%), and fusiform-linear conversion (29%). Subset differences and variables that appear to influence wound contraction are discussed. Secondarily healed wounds in areas with one or more positive contraction variables contract 75%, whereas defects in areas with negative contraction variables contract 55%. CONCLUSIONS: Regional differences in wound contraction of secondarily healed head and neck wounds exist and account for some differences in cosmetic acceptability. Scar location, regardless of the degree of wound contraction, is the most important factor for the final cosmetic outcome.  相似文献   
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前文曾报道从槲寄生中分离及确定五个新黄酮甙的结构。本文报道另一新黄酮化合物(Ⅳ)的分离和结构测定。槲寄生(Viscum coloratura(Kom)Nakai)生药的乙醇提取物,分别用石油醚、醋酸乙酯和正丁醇萃取,正丁醇萃取物经聚酰胺细粉和硅胶低压柱层析,分离得到Ⅳ。通过光谱分析和水解试验,确定Ⅳ的结构为鼠李秦素-3-0-β-D-(6″-β-羟基-β-甲基戊二酸半酯)-葡  相似文献   
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Spencer  HT; Sleep  SE; Rehg  JE; Blakley  RL; Sorrentino  BP 《Blood》1996,87(6):2579-2587
Trimetrexate (TMTX) is an anticancer drug with potential advantages over the more commonly used antifolate, methotrexate (MTX); however, its use has been limited by severe myelosuppression. Retroviral vectors containing mutant dihydrofolate reductase (DHFR) genes have been used to protect bone marrow cells from MTX, suggesting a similar approach could be used for TMTX. We first screened six variants of human DHFR to determine which allowed maximal TMTX resistance in fibroblasts. A variant enzyme containing a Leu-to-Tyr mutation in the 22nd codon (L22Y) was best, allowing a 100-fold increase in resistance over controls. Murine hematopoietic progenitor cells transduced with an L22Y- containing retroviral vector also showed high-level TMTX resistance in vitro. Mice reconstituted with L22Y-transduced bone marrow cells were challenged with a 5-day course of TMTX to determine whether hematopoiesis could be protected in vivo. Transfer of the L22Y vector resulted in consistent protection from TMTX-induced neutropenia and reticulocytopenia at levels that correlated with the proviral copy number in circulating leukocytes. We conclude that the L22Y vector is highly effective in protecting hematopoiesis from TMTX toxicity and may provide a means for increasing the therapeutic utility of TMTX in certain cancers.  相似文献   
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