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101.
Carma A. Heitzmann Robert M. Kaplan Dawn K. Wilson Jeffery Sandler 《Journal of behavioral medicine》1987,10(2):197-211
The treatment of choice for Type II or non-insulin-dependent diabetes mellitus is a behavioral program for the management of weight. However, compliance with this lifelong dietary regimen is often poor. In the current investigation male and female adults with diagnosed Type II diabetes were randomly assigned to either a behavior modification, a cognitive modification, a cognitive-behavior modification, or a control group. Patients were evaluated in terms of weight, percentage of body fat, and glycosylated hemoglobin measures. Men lost signficantly more weight than women and subjects in the behavior modification group lost more weight and demonstrated greater decreases in diabetes control than subjects in the cognitive-behavior modification, cognitive, and control groups. A significant interaction indicated that diabetic men may benefit more from behavioral weight reduction programs than diabetic women. Several explanations for these findings are considered.This work was supported by Grants K04 HL 00809 and R01 AM 27901 from the National Institutes of Health to Robert M. Kaplan. 相似文献
102.
Yasushi Tohi Takashi Nakano Haruyuki Makio Shigekazu Matsui Terunori Fujita Tsutomu Yamaguchi 《Macromolecular chemistry and physics.》2004,205(9):1179-1186
Summary: Bis(phenoxy‐imine) Zr complexes with MAO activation can produce polyethylenes with well‐defined bimodal molecular weight distributions. Polymerization behavior indicates that minor changes in the ligand structures can have a significant effect on the modality of the resulting polyethylenes. Although there is no direct relationship between the bimodal catalytic behavior and the structure of a precatalyst complex in solution, a precatalyst complex having a methyl or methoxy group para to the phenoxy‐oxygen inclined to exhibit bimodal behavior whereas that with a pentafluorophenyl group on the imine‐nitrogen displayed unimodal behavior. Polymerization results suggest that bimodal behavior is linked to the presence of two kinds of cationic active species, which arise from different modes of ligand coordination. A qualitative correlation was found between the calculated amounts of possible cationic active species and the uni‐ and bimodal catalytic behavior. Based on the results obtained, we concluded that the bimodal polyethylenes are produced by two kinds of cationic active species having two available cis‐located sites with cis‐N, trans‐O and cis‐N, cis‐O arrangements. The results introduced herein are rare examples of the production of well‐defined bimodal polyethylenes using a single precatalyst.
103.
The effect of ethanol-induced CYP2E1 on proteasome activity: the role of 4-hydroxynonenal 总被引:6,自引:0,他引:6
Previous studies have shown that the induction of P450 cytochrome 2E1 (CYP2E1) is associated with the loss of proteasomal activities. To correlate the loss of proteasomal activity with CYP2E1 induction, ethanol was fed intragastrically for 1, 3, 7, and 15 days. The maximum induction of CYP2E1 (3.5-fold) occurred after 15 days of ethanol feeding. However, there was no significant decrease in the 26 S chymotrypsin-like and trypsin-like activity over this period of time. When ethanol was given to rats for 1 month, CYP2E1 was significantly induced, and the proteasomal activity was significantly decreased. These results indicate that proteasomal activity was not directly affected by ethanol or CYP2E1 induction. Since 4-hydroxynonenal (4-HNE) concentration was significantly increased at 1 month of ethanol feeding, it was suspected that 4-HNE adduct formation with proteasome subunits could be the mechanism of proteasome inhibition. Using an antibody to 4-HNE adducted proteins in Western blot analysis of the 26 S proteasome fraction isolated from the liver of alcohol fed rats, one extra band appeared around 44 kDa. When the antibody to an ATPase Rpt4 was used to stain the stripped membrane, the same band that was detected with the 4-HNE antibody was detected with the Rpt4 antibody. An adduct of 4-HNE formed with the Rpt4 subunit of 26 S could impede the association of 19 S and 20 S and thus account for the observed decrease of proteasomal activity. 相似文献
104.
Aleksey I. Kovalev Kazuhiko Takeuchi Alexander V. Barzykin Michihiko Asai Mitsuru Ueda Alexander L. Rusanov 《Macromolecular chemistry and physics.》2005,206(20):2112-2121
Summary: The polycondensation of 1‐ethynyl‐2,5‐dihexyl‐4‐iodobenzene in the presence of 1‐ethynyl‐2,5‐dihexyl‐4‐(2‐phenylethynyl)benzene proceeds according to the mechanism of initiated chain growth polycondensation. It has allowed the synthesis of oligomers with a desired molecular weight and a narrow molecular weight distribution. The reasons for the side reaction leading to the formation of diyne compounds are revealed and the presumed mechanism is given. This opens prospects for the preparation of defectless poly(p‐phenyleneethynylene)s with required molecular weights and narrow molecular weight distributions.
105.
Male mice, genetically selected for differences in brain weight or from a heterogeneous (HET) stock, were used to explore potential interactions between genotype and exposure to lead as manifested in activity. At the time of birth dams and their pups were given either water or a 0.5% lead acetate solution as the sole source of fluid. Fluid conditions remained constant throughout the experiment. The effects of chronic lead on activity in young adult mice depended on the genotype of the individual. Specifically, in an open field, HET mice exposed to lead tended to be more active than their control counterparts. Low-and high-brain weight lead-exposed mice at times were hypoactive but this effect depended on the specific nature of the measure.This research was supported in part by National Science Foundation Grant DAR7911233 to Peter J. Donovick and Richard G. Bruggight and by Biomedical Research Support Group Grant 5S077RR07149 to Peter J. Donovick. 相似文献
106.
目的 探讨广州地区围产儿脏器重量及大小的发育规律 .方法 选择 6 2 5例胎龄准确的单胎 ,除外明显浸软、IUGR、水肿儿、巨大胎、有胸腹水者 ,新生儿除外先天性心脏病及有明显疾病的脏器 .根据胎龄分为 6组 ,分别测量围产儿体重、身长和各脏器重量、长度 .进行统计分析 .结果 胰腺、肺发育最早 ,肾脏与肺发育最快 ,出生后脑增长最少而胰腺增长最快 ,肠变异最大等规律 .结论 围产儿脏器资料用于围产儿病理研究有一定意义 相似文献
107.
Frank Greenberg Luther K. Robinson John M. Opitz James F. Reynolds 《American journal of medical genetics. Part A》1989,32(1):90-92
We present a girl with mild manifestations of the Brachmann-de Lange syndrome (BDLS) with gradual change of the phenotype. Her findings support the hypothosis of variability of the phenotypic spectrum of the disorder. 相似文献
108.
氧离子注入增强人工关节软骨材料-UHMWPE的耐磨性 总被引:10,自引:0,他引:10
熊党生 《生物医学工程学杂志》2003,20(4):583-585,596
用高能离子注入机对超高分子量聚乙烯 (U HMWPE)进行了 O+注入改性 ,注入能量为 4 5 0 ke V和 10 0ke V,剂量分别为 1× 10 1 5/cm2 ,5× 10 1 5/cm2和 1× 10 1 6 /cm2。以 Si3N4 球为上销样 ,UHMWPE为下盘样组成摩擦副 ,在销盘摩擦试验机上评价它们在干摩擦和蒸馏水润滑条件下的磨损性能。结果表明 ,几种注入工艺均增强了UHMWPE的耐磨性 ,但提高了其摩擦系数 ,其中以能量为 4 5 0 Ke V,剂量为 5× 10 1 5/cm2的注入样品耐磨性最好。未注入 U HMWPE的磨损主要表现为黏着、塑性变形和犁沟 ,注入 U HMWPE的磨损主要为表面硬化层疲劳裂纹的萌生、扩展、剥落及磨粒磨损 相似文献
109.
壳聚糖醋酸溶液对凝血作用的研究 总被引:1,自引:0,他引:1
研究了不同脱乙酰度和不同分子量壳聚糖醋酸溶液的凝血作用。发现壳聚糖醋酸溶液使抗凝血液中红细胞发生了明显的聚集和变形。通过不同分子量和脱乙酰度壳聚糖的促红细胞聚集实验,证明了低脱乙酰度壳聚糖(60%~70%)使红细胞聚集效果更好,分子量在105~106范围内作用不十分明显。对血液的凝血酶时间(TT)、凝血酶原时间(PT)、活化部分促凝血酶原激酶时间(APTT)和纤维蛋白原浓度(FIB)的测定结果验证了壳聚糖醋酸溶液凝血机理不依赖于血小板和常规“瀑布”凝血机制。 相似文献
110.
Yasushi Nakayama Junji Saito Hideki Bando Terunori Fujita 《Macromolecular chemistry and physics.》2005,206(18):1847-1852
Summary: Fluorinated bis(phenoxy‐imine)Ti complexes 1 – 3 combined with MgCl2/i‐BunAl(OR)3−n (MgCl2‐supported catalysts) were able to polymerize propylene in a living fashion at room temperature to provide slightly to highly syndiotactic poly(propylenes) (PPs) with extremely narrow distributions of molecular weight. These represent the first examples of MAO‐ and borate‐free group 4 metal‐based living catalysts. The supported complexes 2 and 3 formed PPs with higher syndiotacticity and Tm's than the corresponding homogeneous MAO‐activation systems (e.g., 3 : rr 97%, Tm 155 °C; MAO activation: rr 93%, Tm 152 °C). The measured Tm of 155 °C represents the highest known Tm for syndiotactic PPs synthesized at room temperature.