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91.
We examined whether behavioral problems in childhood and adolescence are associated with young adults' BMI and obesity, and tested whether childhood behavioral problems have a greater impact on young adults' obesity than adolescent behavioral problems. The data were from the Mater‐University of Queensland Study of Pregnancy (MUSP) and Its Outcomes, a population‐based birth cohort study commenced in Brisbane, Australia, in 1981. A subsample of 2,278 children for whom we had prospective information on their behavioral problems at ages 5 and 14 and measured BMI, and its categories (normal, overweight, and obese) at age 21 was chosen. Young adults who experienced behavioral problems at ages 5 or 14 had a greater average BMI and were more likely to be obese compared to young adults without behavioral problems at both ages. The childhood onset group was at greater risk of becoming obese by age 21 compared to the adolescent onset group (P = 0.04). These associations remained consistent after adjusting for a variety of potential covariates including maternal characteristics (i.e., demographics and life style), child dietary patterns, family meals, television (TV) watching, and participation in sports and exercise at 14 years. Childhood as well as persistent behavioral problems during childhood and adolescence predicts young adults' BMI and obesity. Although further studies are needed to confirm this association, there is a need for close monitoring of children presenting with behavioral problems.  相似文献   
92.
We examined the prospective association of childhood BMI z‐score and BMI categories (normal or overweight) with young adult diabetes, controlling for early life, childhood, and adolescence factors. A subsample of 2,639 young adults from the Mater–University study of pregnancy (MUSP) and its outcomes, a prospective birth cohort who were born in Brisbane, Australia and for whom we had measured height and weight at 5 years and self‐reported diabetes at age 21 years. The risk of developing diabetes by age 21 years was greater among young adults who had greater BMI z‐score or were overweight at age 5 years than those who had normal BMI at age 5 years. Young adults who were overweight at age 5 years had an increased odds ratio of 2.60 (95% confidence interval (CI): 1.29, 5.22, in age‐ and sex‐adjusted model) of experiencing diabetes by age 21 years. Adjustment for potential confounders and mediators including intrauterine environmental factors, childhood dietary patterns, television watching, participation in sports and exercise, and current weight, did not substantively alter these associations. Overweight and increasing BMI z‐score at childhood is an independent predictor of young adult's type 1 and type 2 diabetes. Findings of this study suggest that childhood BMI may be central to the development and rising incidence of all diabetes.  相似文献   
93.
The phenyldi(2-thienyl)phosphine (PhPTh2) complexes [Os3(CO)12−n(PhPTh2)n] (n = 1-3) (1-3) have been prepared. Thermolysis of 1 and either 2 or 3 in octane affords carbon-hydrogen bond activation products [Os3(CO)93-PPhTh(C4H2S)}(μ-H)] (4) and [Os3(CO)8(PPhTh2){μ3-PPhTh(C4H2S)}(μ-H)] (5), respectively. Both exist as isomeric mixtures differing in the relative positions of phenyl and thienyl substituents with respect to the triosmium centre. The nature of the process has been confirmed by a single crystal X-ray diffraction analysis of 4.  相似文献   
94.
95.
The effects of pelvic endometrial implants on the overall reproductive potential of female rats were investigated. After homologous transplantation in the peritoneum, the ectopic endometrium developed into highly vascularized nodes that gradually increased in mass until the 9th week postsurgery and then plateaued. In the presence of these implants, overall reproductive function was adversely affected. The effect was of greatest magnitude during 50-70 days posttransplantation. As compared with values in corresponding controls, ovulation was reduced by 43% (6 of 14) (p < 0.05), mating rate was reduced by 44% (12 of 27) (p < 0.025), and premature termination of pregnancy occurred in 34% (5 of 15) of rats. Wastage of pregnancy, which included complete termination or reduction of fetal number, occurred during the postimplantation course of gestation. Furthermore, 100% of the rats with transplants failed to respond to the copulomimetic stimulation for the induction of pseudopregnancy (p < 0.01, compared with corresponding controls). However, on exposure to vasectomized males, 46% (6 of 13) of these rats exhibited development of pseudopregnancy (p < 0.05, compared with corresponding group receiving copulomimetic stimulation). Increased rate of mating failure and differential pseudopregnancy rates after copulomimetic and natural cervical stimulation suggest that the rats with endometrial explants possibly had an absence or a short appearance of behavioral estrus. Hormonal assessment during the preovulatory phase showed a tendency toward lower mean levels of preovulatory estradiol and significantly lower LH (p < 0.01) and progesterone (p < 0.01) concentrations. The adversely affected reproductive functions may be a secondary consequence of these altered endocrine milieus.  相似文献   
96.
97.
 We compared the vertical distribution (0–25 cm) of arbuscular mycorrhizae, extraradical hyphae, and glomalean spores at grain-filling of corn under conventional tillage versus no tillage. Root colonization, total hyphae density, and spore density were correlated, and were highest at a depth of 0–15 cm in soil. Tillage significantly reduced total hypha density and spore density at 0–5 cm depth, but did not affect root colonization. Plowing below 15 cm is likely to diminish AM fungus inocula in the rooting zone of establishing seedlings. Accepted: 19 April 1998  相似文献   
98.
Six different bioassay methods were evaluated using propargite (Omite 30% wettable powder (WP) and fenbutatin oxide (Torque 50% (WP) and 55% suspension concentrate (SC)) with twospotted spider mite, Tetranychus uriticae Koch (TSM) and European red mite, Panonychus ulmi Koch (ERM) to document their utility and precision for estimating median lethal concentrations (LC). For each method, two post-treatment exposure periods and mortality criteria were used. Post-treatment exposure period and mortality criterion had a significant influence on the precision of LC50 estimates for all tested miticides with all bioassays methods. Twenty four hour (h) post-treatment exposure was found to be the most suitable for the slide dip and Petri dish methods while 48h was the most appropriate for leaf disc methods. Scoring moribund mites as dead was the most satisfactory criterion for ensuring that biossays were as simple and precise as possible. The Petri dish residue-Potter tower method (PDR-PT) estimated the responses of TSM and ERM to propargite with high precision. The same method was not as precise for fenbutatin oxide formulations. Because significant mite run-off occurred with the leaf disc methods, their precision was not fully established. The slide dip method gave less precise estimates of LC50 values for propargite (WP) and fenbutatin oxide (WP), while the same method gave more precise LC50 estimates for fenbutatin oxide (SC) than the PDR-PT method. The toxicity of candidate miticides was found to be method-and species-dependent.  相似文献   
99.
S Kabir 《Microbios》1977,20(79):47-62
The number, nature and organization of the outer membrane proteins of Salmonella typhimurium have not yet been resolved. Therefore these proteins were isolated using a concentrated solution of guanidine hydrochloride and studied using different analytical techniques. Upon chromatography on Sephadex G-200 four fractions were obtained. Only the fraction containing a protein of molecular weight 13,000 produced immunoprecipitation reactions with the antisera raised against the whole bacteria. On polyacrylamide gel electrophoresis in the presence of sodium dodecyl sulphate, 7 major proteins were found, with molecular weights between 13,000 and 43,000. Isoelectric focusing on 4.6% polyacrylamide gels resolved the outer membrane proteins into 10 bands with apparent isoelectric points between 5.0 and 8.4. Finally these proteins could be further resolved into as many as 50 spots where a two-dimensional electrophoresis was carried out with isoelectric focusing in the first dimension, and polyacrylamide gel electrophoresis in the presence of sodium dodecyl sulphate in the second dimension. These results demonstrated that the outer membrane proteins of S. typhimurium are extremely heterogeneous. To investigate the mode of organization of lipopolysaccharides in the outer membrane, the membrane proteins were separated by the liquid isoelectric focusing technique. Lipopolysaccharides were primarily found to be associated with a protein of isoelectric point 7.8.  相似文献   
100.
High-risk neuroblastoma (NB) represents a major clinical challenge in pediatric oncology due to relapse of metastatic, drug-resistant disease, and treatment-related toxicities. An analysis of 1235 primary NB patient dataset revealed significant increase in AKT1 and AKT2 gene expression with cancer stage progression. Additionally, Both AKT1 and AKT2 expression inversely correlate with poor overall survival of NB patients. AKT1 and AKT2 genes code for AKT that drive a major oncogenic cell signaling pathway known in many cancers, including NB. To inhibit AKT pathway, we repurposed an antiviral inhibitor BX-795 that inhibits PDK1, an upstream activator of AKT. BX-795 potently inhibits NB cell proliferation and colony growth in a dose-dependent manner. BX-795 significantly enhances apoptosis and blocks cell cycle progression at mitosis phase in NB. Additionally, BX-795 potently inhibits tumor formation and growth in a NB spheroid tumor model. We further tested dual therapeutic approaches by combining BX-795 with either doxorubicin or crizotinib and found synergistic and significant inhibition of NB growth, in contrast to either drug alone. Overall, our data demonstrate that BX-795 inhibits AKT pathway to inhibit NB growth, and combining BX-795 with current therapies is an effective and clinically tractable therapeutic approach for NB.  相似文献   
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