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91.
Relatively little research has assessed the association between obesogenic behaviors in parents and their children. The objective of the present analysis was to examine cross-sectional associations in television (TV)/video viewing, sugar-sweetened beverage intake, and fast food intake between mothers and their preschool aged children. We studied baseline data among 428 participants in High Five for Kids, a randomized controlled trial of behavior change among overweight and obese children of ages 2-6.9 years. The main exposures were whether mothers viewed TV/videos <1 h/day, drank <1 serving/day of sugar-sweetened beverages, and ate fast food <1 time/week. The main outcomes were whether children met these goals for the same behaviors. Using multivariate logistic regression adjusted for maternal and child characteristics, we estimated odds ratios of children meeting the behavioral goals. The majority of mothers ate fast food <1 time/week (73%) and drank <1 serving/day of sugar-sweetened beverages (73%), while few mothers viewed <1 h/day of TV/videos (31%). Most children met the fast food goal (68%), but not the goals for sugar-sweetened beverages (31%) or TV/video viewing (13%). In adjusted models, the odds ratios for a child meeting the goal were 3.2 (95% confidence interval (CI) 1.7, 6.2) for TV/video viewing, 5.8 (95% CI 2.8, 12.0) for sugar-sweetened beverage intake, and 17.5 (95% CI 9.8, 31.2) for fast food intake if their mothers met the goal for the same behavior. Obesogenic behaviors of mothers and preschool aged children were strongly associated. Our findings lend support to obesity prevention strategies that target parental behavior and the family environment.  相似文献   
92.
Research scientists and IACUC members are faced with the difficult task of balancing the necessity of using animals for experimental research and their mandate to protect the welfare of those animals used in that research. One way to reduce the number of research animals would be to reuse them, but the regulations do not specifically address this topic. To learn more about the reuse of research animals, the authors conducted an online survey of animal facilities involved in preclinical studies. Their results suggest that animal reuse is a common practice in the field.  相似文献   
93.
Many physicians remain uncertain about prescribing hormone therapy for symptomatic women at the onset of menopause. The American Society for Reproductive Medicine (ASRM) convened a multidisciplinary group of healthcare providers to discuss the efficacy and risks of hormone therapy for symptomatic women, and to determine whether it would be appropriate to treat women at the onset of menopause who were complaining of menopausal symptoms. MAJOR FINDINGS: Numerous controlled clinical trials consistently demonstrate that hormone therapy, administered via oral, transdermal, or vaginal routes, is the most effective treatment for vasomotor symptoms. Topical vaginal formulations of hormone therapy should be preferred when prescribing solely for the treatment of symptoms of vulvar and vaginal atrophy. Data from the Women's Health Initiative indicate that the overall attributable risk of invasive breast cancer in women receiving estrogen plus progestin was 8 more cases per 10,000 women-years. No increased risk for invasive breast cancer was detected for women who never used hormone therapy in the past or for those receiving estrogen only. Hormone therapy is not effective for the treatment of cardiovascular disease and that the risk of cardiovascular disease with hormone therapy is principally in older women who are considerably postmenopause. CONCLUSIONS: Healthy symptomatic women should be offered the option of hormone therapy for menopausal symptoms. Symptom relief with hormone therapy for many younger women (at the onset of menopause) with menopausal symptoms outweighs the risks and may provide an overall improvement in quality of life. Hormone therapy should be individualized for symptomatic women. This involves tailoring the regimen and dose to individual needs.  相似文献   
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A rabbit antiserum directed against purified human placental aromatase was used for immunohistochemical localization of the enzyme in rat ovaries. Immunostaining was conducted on tissue from animals at various ages and in different reproductive states: immature; immature, eCG-treated; immature pseudopregnant; adult cycling; and adult pregnant. Various labeling protocols were employed (e.g. horseradish peroxidase-conjugated secondary antibody, peroxidase-antiperoxidase, and avidin-biotin-peroxidase on fresh frozen and Bouin's fixed paraffin-embedded sections), but the avidin-biotin-peroxidase method on paraffin sections proved to be superior to the others. In immature rats, most of the immunostaining, which was quite weak, was limited to the stroma. After stimulation with eCG, some of the granulosa cells of antral follicles exhibited immunostaining; in pseudopregnant rats, most staining occurred in the luteal cells. In mature animals, the corpora lutea of pregnant and cycling rats demonstrated the greatest degree of immunostaining. No significant immunoreactivity was detected in pre-antral follicles, but in early antral follicles and preovulatory follicles, both theca and granulosa cells exhibited immunostaining. Aromatase enzymatic activity was also determined on ovarian microsomal fractions of eCG-treated immature animals, pregnant animals at term, and cycling animals. Furthermore, enzyme activity and estradiol concentrations were examined after ovaries from proestrous rats were dissected into follicular, luteal, and residual components. Activity was found in all regions and correlated with immunostaining and estrogen production. These results argue against a model in which all the immunoreactive/enzymatically active protein is localized in granulosa cells of Graafian follicles and suggest that corpora lutea may be involved in estrogen synthesis during the rat estrous cycle as well as during pregnancy.  相似文献   
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 Bestatin (ubenimex), an inhibitor of aminopeptidase, is an oral immunomodulator that binds to CD13 (aminopeptidase N) on macrophages/monocytes. To examine its immunomodulatory effect after high-dose therapy and autologous bone marrow transplantation (BMT), a dose-finding phase Ib trial was conducted with 30 Hodgkin’s disease and non-Hodgkin’s lymphoma patients who received no drug (control), 10 and 30 mg (low dose), or 90 and 180 mg (high dose) of bestatin daily for 60 days following autologous BMT. Bestatin administration was initiated when the absolute neutrophil count was greater than 250/mm3 on 2 consecutive days. The serum neopterin levels, an indicator of monocyte/macrophage activation, increased in the high-dose group compared to the control group (not significantly) and the low-dose group (significantly). Similarly, the colony-stimulating activity in the sera was significantly increased in the high-dose group compared to the control and low-dose groups. We also examined the expression of cell-surface markers on monocytes in these patients by fluorescent cytometry analysis. There was no significant difference either in the frequency or absolute number of monocytes (CD14+) among the three groups at any time. However, a significant increase in the frequency of CD16(FcgRIII)-positive monocytes (a marker of activation) was observed in the high-dose group compared to controls from day 14 to day 60 after the start of bestatin administration. Further, the frequency of HLA-DR+ monocytes (another marker of activation) was significantly increased in the high-dose group. These results indicate that bestatin at higher doses (90 and 180 mg daily), but not lower doses, activates macrophages/monocytes, as demonstrated by phenotypic marker (HLA-DR and CD16) up-regulation, and this provides augmentation of neopterin and colony-stimulating activity in the serum of patients following autologous BMT. Received: 24 June 1996 / Accepted 13 September 1996  相似文献   
99.
Previous studies have shown that cytosolic glycerol-3-phosphate dehydrogenase (GPDH; EC 1.1.1.8) can be induced by glucocorticoids in mammalian brain, mammary gland, and thymus, but it was thought that no induction occurred in liver. We report here that GPDH is induced by glucocorticoids in several lines of hepatoma cells and in rat hepatocytes cultured in vitro. When rat hepatoma cells of clone FU5AH were exposed to 3 μM hydrocortisone (HC) for 3 days, GPDH specific activity increased greater than sixfold over control. The rate and extent of induction were similar in exponentially growing and stationary-phase cultures of cells. Four other hepatoma cell lines were inducible to a lesser extent, and three lines were not inducible. GPDH was also induced by glucocorticoids in cultures of hepatocytes isolated from livers of 6-day-old rats. The enzyme was induced threeto fourfold by the synthetic glucocorticoid, dexamethasone, in the presence of 1 nM insulin, but the induction was not observed in the absence of insulin.  相似文献   
100.
The objective have been to establish if those ions which are known to change the stability of the structure of proteins, have any influence on the properties of ionizable polypeptides. Potentiometric titrations and complementary optical rotation data are presented for aqueous solutions of poly-L -lysine (PLL) in the presence of KSCN, KCl, and KF, and for poly(L -glutamic acid) (PLGA) in the presence of KSCN, KCl, and LiCl. The following measured quantities which are affected by salt concentration were obtained: intrinsic pK (pK0), slope of pKapp versus degree of ionization (α) curves, the degree of ionization at which the helix to coil transition occurs, and the free energy of this transition for the uncharged molecule (δG°hel). The effects of nonspecific salts (KCl and LiCl for PLL and KSCN and KCl for PLGA) are small, and about, as expected from general electrostatic considerations. In line with the observations made with isoelectric and cat ionic collagen, specific, effects were noted with KSCN–PLL and with LiCl–PLGA. In the presence of KSCN, the poly-L -lysine helix becomes stabilized at much lower degree of ionization than in the presence of KCl, and the slope of the pKapp versus α plots is greatly reduced. However, ΔG°hel (for the uncharged molecule) is not affected, and pK0 is only slightly higher. We interpret these data in terms of binding of SCN? primarily to the side-chain amino groups (both to R? NH3+ and to R? NH2) solutions. (L -glutamic acid) in LiCl solution has its transition at the same α value as in KCl solution. However, both the slopes of the pKapp versus α plots and the absolute values of ΔG°hel are lower than in KCl solution. We interpret these results in terms of binding of Li+ to side chains as well as to the peptide bond.  相似文献   
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