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71.
Midlife women tend to gain weight with age, thus increasing risk of chronic disease. The purpose of this study was to examine associations between overweight/obesity and behavioral factors, including eating frequency, in a cross‐sectional national sample of midlife women (n = 1,099) (mean age = 49.7 years, and BMI = 27.7 kg/m2). Eating behaviors and food and nutrient intakes were based on a mailed 1‐day food record. BMI was calculated from self‐reported height and weight, and level of physical activity was assessed by self‐reported questionnaire. After exclusion of low‐energy reporters (32% of sample), eating frequency was not associated with overweight/obesity (P > 0.05) and was not different between BMI groups (normal, 5.21 ± 1.79; overweight, 5.16 ± 1.74; obese, 5.12 ± 1.68, P = 0.769). Adjusted logistic regression showed that eating frequency, snacking frequency, breakfast consumption, eating after 10 pm and consuming meals with children or other adults were not significantly associated with overweight/obesity. Total energy intake increased as eating frequency increased in all BMI groups, however, obese women had greater energy intake compared to normal weight women who consumed the same number of meals and snacks. Intake of fruit and vegetables, whole grains, dietary fiber, dairy, and added sugars also increased as eating frequency increased. While eating frequency was not associated with overweight/obesity, it was associated with energy intake. Thus, addressing total energy intake rather than eating frequency may be more appropriate to prevent weight gain among midlife women.  相似文献   
72.
73.
BACKGROUND: The mechanism for the disappointing late outcome following stenting of bifurcation lesions is unclear. This prospective observational study aims to evaluate culotte stent deployment and dimensions with intravascular ultrasound (IVUS). PATIENTS AND METHODS: Patients with bifurcation stenoses were treated using two stents in a culotte configuration. After optimizing the angiographic appearance of both stents, IVUS was used to evaluate both limbs of the culotte. The main outcome measures were cross-sectional area (CSA) and minimal lumen diameter (MLD) assessed by IVUS. RESULTS: Within the culotte stent, the final mean CSA in the main limb was 6.1 mm(2) (97% of reference) and in the side-limb was 5.9 mm(2) (97% of reference). However, in each case, the minimum CSA and IVUS MLD of both limbs was at the bifurcation point. For all patients, the final mean CSA at the bifurcation point of the main limb was 4.3 mm(2) (70% of main stent) and of the side-limb was 4.4 mm(2) (75% of side stent). The IVUS MLD at the bifurcation point of the main limb was 2.1 mm (78% of main stent) and of the side-limb was 2.1 mm (84% of the side stent). Importantly, this significant residual stenosis was not detectable with quantitative coronary angiography. CONCLUSIONS: IVUS evaluation of culotte stents is feasible. The minimum IVUS CSA and MLD of both limbs of the culotte stent is at the bifurcation point. Despite an optimal angiographic appearance a significant residual stenosis was noted with IVUS at each bifurcation point.  相似文献   
74.
The distribution of Na+ pump sites (Na+-K+-ATPase) in the secretory epithelium of the avian salt gland was demonstrated by freeze-dry autoradiographic analysis of [(3)H] ouabain binding sites. Kinetic studies indicated that near saturation of tissue binding sites occurred when slices of salt glands from salt-stressed ducks were exposed to 2.2 μM ouabain (containing 5 μCi/ml [(3)H]ouabain) for 90 min. Washing with label-free Ringer's solution for 90 min extracted only 10% of the inhibitor, an amount which corresponded to ouabain present in the tissue spaces labeled by [(14)C]insulin. Increasing the KCl concentration of the incubation medium reduced the rate of ouabain binding but not the maximal amount bound. In contrast to the low level of ouabain binding to salt glands of ducks maintained on a freshwater regimen, exposure to a salt water diet led to a more than threefold increase in binding within 9-11 days. This increase paralleled the similar increment in Na+-K+-ATPase activity described previously. [(3)H]ouabain binding sites were localized autoradiographically to the folded basolateral plasma membrane of the principal secretory cells. The luminal surfaces of these cells were unlabeled. Mitotically active peripheral cells were also unlabeled. The cell-specific pattern of [(3)H]ouabain binding to principal secretory cells and the membrane-specific localization of binding sites to the nonluminal surfaces of these cells were identical to the distribution of Na+-K+-ATPase as reflected by the cytochemical localization of ouabain-sensitive and K+-dependent nitrophenyl phosphatase activity. The relationship between the nonluminal localization of Na+-K+-ATPase and the possible role of the enzyme n NaCl secretion is considered in the light of physiological data on electrolyte transport in salt glands and other secretory epithelia.  相似文献   
75.
Myocutaneous flaps based on the gluteus maximus muscle, and its blood supply, have many advantages for the surgical repair of pressure sores in paraplegics. These are described, as well as the techniques used in various areas.  相似文献   
76.
Spotted‐wing drosophila, Drosophila suzukii (Matsumura), is an invasive pest affecting fruit production in many regions of the world. Insecticides are the primary tactic for controlling D. suzukii in organic as well as conventional production systems. Organic growers have a greater challenge because fewer insecticides are approved for use in organic agriculture. The most effective organically approved product is spinosad, but alternatives are needed because of label restrictions limiting the number of applications per year, toxicity to beneficial arthropods and the risk of developing resistance. We evaluated several organically approved insecticides against D. suzukii in laboratory assays and field trials conducted on organic blueberry and raspberry farms. Spinosad was consistently the most effective insecticide, but a few other insecticides such as azadirachtin + pyrethrins, Chromobacterium subtsugae and sabadilla alkaloids showed moderate activity. None of the treatments had long residual activity. Mortality started to decline by 3 days after treatment, and by 5 days after application, the treatments were not different from the controls. These products may be useful in rotation programmes, necessary for reducing reliance on spinosad and mitigating resistance. Cultural and biological control approaches are needed in fruit production for D. suzukii management, but insecticides will likely continue to be the dominant management tactic while these other approaches are being optimized and adopted.  相似文献   
77.
Eukaryotic cytochrome c oxidase (CcO) and homologous prokaryotic forms of Rhodobacter and Paraccocus differ in the EPR spectrum of heme a. It was noted that a histidine ligand of heme a (H102) is hydrogen bonded to serine in Rhodobacter (S44) and Paraccocus CcOs, in contrast to glycine in the bovine enzyme. Mutation of S44 to glycine shifts the heme a EPR signal from g(z) = 2.82 to 2.86, closer to bovine heme a at 3.03, without modifying other properties. Mutation to aspartate, however, results in an oppositely shifted and split heme a EPR signal of g(z) = 2.72/2.78, accompanied by lower activity and drastically inhibited intrinsic electron transfer from CuA to heme a. This intrinsic rate is biphasic; the proportion that is slow is pH dependent, as is the relative intensity of the two EPR signal components. At pH 8, the heme a EPR signal at 2.72 is most intense, and the electron transfer rate (CuA to heme a) is 10-130 s(-1), compared to wild-type at 90,000 s(-1). At pH 5.5, the signal at 2.78 is intensified, and a biphasic rate is observed, 50% fast (approximately wild type) and 50% slow (90 s(-1)). The data support the prediction that the hydrogen-bonding partner of the histidine ligand of heme a is one determinant of the EPR spectral difference between bovine and bacterial CcO. We further demonstrate that the heme a redox potential can be dramatically altered by a nearby carboxyl, whose protonation leads to a proton-coupled electron transfer process.  相似文献   
78.
Brown adipose tissue is a thermogenic organ that dissipates stored energy as heat to maintain body temperature. This process may also provide protection from development of diet-induced obesity. We report that the bioactive lipid mediator lysophosphatidic acid (LPA) markedly decreases differentiation of cultured primary brown adipocyte precursors, whereas potent selective inhibitors of the LPA-generating enzyme autotaxin (ATX) promote differentiation. Transgenic mice overexpressing ATX exhibit reduced expression of brown adipose tissue-related genes in peripheral white adipose tissue and accumulate significantly more fat than wild-type controls when fed a high-fat diet. Our results indicate that ATX and its product LPA are physiologically relevant negative regulators of brown fat adipogenesis and are consistent with a model in which a decrease in mature peripheral brown adipose tissue results in increased susceptibility to diet-induced obesity in mice.  相似文献   
79.
Although benthic motile invertebrate communities encompass the vast majority of coral reef diversity, their response to habitat modification has been poorly studied. A variety of benthic species, particularly decapods, provide benefits to their coral host enabling them to cope with environmental stressors, and as a result benefit the overall diversity of coral-associated species. However, little is known about how invertebrate assemblages associated with corals will be affected by global perturbations, (either directly or indirectly via their coral host) or their consequences for ecosystem resilience. Analysis of a ten year dataset reveals that the greatest perturbation at Moorea over this time was an outbreak of the corallivorous sea star Acanthaster planci from 2006 to 2009 impacting habitat health, availability and size structure of Pocillopora spp. populations and highlights a positive relationship between coral head size and survival. We then present the results of a mensurative study in 2009 conducted at the end of the perturbation (A. planci outbreak) describing how coral-decapod communities change with percent coral mortality for a selected coral species, Pocillopora eydouxi. The loss of coral tissue as a consequence of A. planci consumption led to an increase in rarefied total species diversity, but caused drastic modifications in community composition driven by a shift from coral obligate to non-obligate decapod species. Our study highlights that larger corals left with live tissue in 2009, formed a restricted habitat where coral obligate decapods, including mutualists, could subsist. We conclude that the size structure of Pocillopora populations at the time of an A. planci outbreak may greatly condition the magnitude of coral mortality as well as the persistence of local populations of obligate decapods.  相似文献   
80.
The polymorphic minor histocompatibility Ag HA-1 locus encodes two peptides, HA-1(H) and HA-1(R), with a single amino acid difference. Whereas the immunogenicity of the HA-1(R) allele has not yet been shown, the nonameric HA-1(H) peptide induces HLA-A2-restricted cytotoxic T cells in vivo and in vitro. It is not known whether the mHag HA-1(H) or HA-1(R) associates with other HLA class I molecules. Therefore, the polymorphic regions of both HA-1 alleles were analyzed to identify HLA class I binding peptides that are properly processed by proteasomal degradation. Peptide binding analyses were performed for all nonameric HA-1(H/R) peptides for binding to nine HLA class I molecules with >10% prevalence in the Caucasian population and for seven nonameric/decameric HA-1(H/R) peptides predicted to bind to HLA-A3, -B14, and -B60. Only the nonameric KECVL(H)/(R)DDL and decameric KECVL(H)/(R)DDLL peptides showed strong and stable binding to HLA-B60. In vitro digestion of 29-aa-long HA-1 peptides by purified 20S proteasomes revealed proper cleavage at the COOH termini of both HLA-B60 binding HA-1(H) and HA-1(R) peptides. In subsequent analyses, dendritic cells pulsed with the nonameric HA-1(R) peptide did not induce CTLs that recognize the natural HLA-B60/HA-1(R) ligand. In contrast, dendritic cells pulsed with the nonameric HA-1(H) peptide induced IFN-gamma-secreting T cells specific for the natural HLA-B60/HA-1(H) ligand in three HLA-B60(+) HA-1(RR) individuals, demonstrating the immunogenicity of the HLA-B60/HA-1(H) ligand. In conclusion, this study shows a novel HLA-B60-restricted T cell epitope of the minor histocompatibility Ag HA-1 locus.  相似文献   
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