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71.
72.
A simple model of the line activity of a hybrid lipid (e.g., POPC) with one fully saturated chain and one partially unsaturated chain demonstrates that these lipids preferentially pack at curved interfaces between phase-separated saturated and unsaturated domains. We predict that the domain sizes typically range from tens to hundreds of nm, depending on molecular interactions and parameters such as molecular volume and area per headgroup in the bulk fluid phase. The role of cholesterol is taken into account by an effective change in the headgroup areas and the domain sizes are predicted to increase with cholesterol concentration.  相似文献   
73.
A long term study of warblers in the Himalayas reveals a surprising contrast in the effects of warm springs as opposed to warm summers on a signaling trait, emphasizing the need to consider year-round influences of the environment on morphological variation.  相似文献   
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At present, the putative clinical use of the musculocutaneous and ostomusculocutaneous serratus anterior flaps has been compromised by the risk of partial or total necrosis of the skin overlying the lower part of the serratus anterior muscle. Therefore, the aim of this study was to delineate a skin area vascularized by perforant musculocutaneous branches of arteries stemming from the lower segment of the anterior serrated muscle. Black ink was injected in thoracodorsal artery branches for the serratus anterior muscle in 50 human cadavers before the autopsies (the study was approved by the Institutional Review Board). The surface area of the labeled skin was determined and its borders delineated by means of transparent millimeter grid. Planimetry data were subsequently analyzed with the aid of PC computer program. The results show that the calculated mean surface area (143.79 +/- 2.68 x 2.077; range 138.22-149.36 cm2) of the skin vascularized by perforant musculocuaneous branches stemming from the lower segment of the anterior serrated muscle, can serve as a reliable guide for taking serratus anterior flap in any patient. Therefore, appropriately sized musculocutaneous or osteomusculocutaneous serratus anterior flap can be safely and efficiently used in plastic and reconstructive surgery.  相似文献   
76.
We compared the number/percentages of naive and memory CD4+ T-cells, CD38+ CD8+ T-cells, and CD28+ CD4+ and CD28+ CD8+ T-cells in patients with advanced HIV disease (baseline CD4+ count < 100) with those with less advanced (baseline CD4+ cell count > 100) HIV disease during 4 years of suppressive highly active antiretroviral therapy. This prospective, longitudinal study included 30 treatment-naive patients and 32 controls. Advanced HIV-infected patients (n = 13) gained more CD4+ T-cells than less advanced patients (n = 11) at 1 month (median: 60 vs. 36 microL(-1)), 3 months (86 vs. 14), 6 months (111 vs. 23), 12 months (174 vs. 47), 24 months (162 vs. 72) and 48 months (257 vs. 123) (P = 0.15, P < 0.001, P = 0.026, P = 0.021, P = 0.1 and P = 0.06, respectively). Advanced patients gained more naive CD4+ T-cells at 48 months compared to less advanced patients (27.3 vs. 11.4%, P = 0.05). The relative gain in memory CD4+ T-cells was greater in advanced vs. less advanced patients at 1 month (median: 6.4 vs. 1.4%), 3 months (4.3 vs. 2.0), 6 months (6.7 vs. 1.6), 12 months (6.9 vs. 2.4), 24 months (7.5 vs. 3.1) and 48 months (11.3 vs. 6.8) (P = 0.002, P = 0.013, P < 0.001, P = 0.004, P = 0.001 and P = 0.015, respectively). At 48 months, CD38+ CD8+ T-cells and naive CD4+ T-cells reached normal values (9.2%, P = 0.869 vs. controls and 47.5%, P = 0.699, respectively) in less advanced patients, as did CD38+ CD8+ T-cells in advanced patients (4.7%, P = 0.309 vs. controls). The kinetics of naive and memory CD4+ T-cell reconstitution is different in less advanced compared to advanced HIV patients.  相似文献   
77.
Most theories of kin selection assume that animals are able to distinguish relatives from non-relatives. This is especially difficult in situations where mixed parentage precludes that relatedness is recognised by familiarity. Recent work shows that, within the same brood, young bluegill sunfish that are fathered by cuckolders--but not those sired by parental males--pick out their relatives using self-referent phenotype matching and not familiarity.  相似文献   
78.
Hip joint centre (HJC) localization is used in several biomedical applications, such as movement analysis and computer-assisted orthopaedic surgery.The purpose of this study was to validate in vitro a new algorithm (MC-pivoting) for HJC computation and to compare its performances with the state-of-the-art (least square approach–LSA). The MC-pivoting algorithm iteratively searches for the 3D coordinates of the point belonging to the femoral bone that, during the circumduction of the femur around the hip joint (pivoting), runs the minimum length trajectory. The algorithm was initialized with a point distribution that can be considered close to a Monte Carlo simulation sampling all around the LSA estimate.The performances of the MC-pivoting algorithm, compared with LSA, were evaluated with tests on cadavers. Dynamic reference frames were applied on both the femur and the pelvis and were tracked by an optical localizer.Results proved the algorithm accuracy (1.7 mm±1.6, 2.3—median value±quartiles), reliability (smaller upper quartiles of the errors distribution with respect to LSA) and robustness (reduction of the errors also in case of large pelvis displacements).  相似文献   
79.
Sexually dimorphic traits often signal the fitness benefits an individual can provide to potential mates. In species with altricial young, these signals may also predict the level of parental care an individual is expected to provide to shared offspring. In this study, we tested three hypotheses that traditionally relate sexually dimorphic traits to parental care in two populations of North American barn swallows Hirundo rustica erythrogaster. The good parent hypothesis predicts a positive relationship between an individual's ornamentation and his or her care whereas the differential allocation (more care given by individuals when paired to high quality mates) and reproductive compensation (more care given by individuals when paired to low quality mates) hypotheses predict that an individual's level of parental investment is relative to the quality of their mate. Male and female North American barn swallows have colorful ventral feathers and elongated tail streamers, but there is evidence that ventral color, not tail streamer length, predicts measures of seasonal reproductive success. Accounting for the positive correlation between within‐pair feeding rates and other potentially confounding variables in all of our models, we found no support for the good parent hypothesis because in both males and females, traits shown to be under sexual selection did not predict feeding rates in either sex. However, our data reveal that male coloration, and not streamer length, predicted a female's provisioning rate to shared offspring (females fed more when paired with darker individuals) in two separate populations, supporting the differential allocation, but not the reproductive compensation hypothesis. Because genetic traits have also been shown to affect parental investment, we evaluated this variable as well and found that a male's paternity did not have significant effects on either male or female feeding rates. Overall, our results suggest that females do not pair with darker males in order to gain direct benefits in terms of his expected levels of parental care to shared offspring, but do themselves invest greater levels of care when paired to darker males. Further, our results are consistent with previous studies which suggest that ventral feather color, not streamer length, is a target of sexual selection in North American populations of barn swallow because females invested more in their offspring when paired to darker mates.  相似文献   
80.
Primary gastric non Hodgkin lymphoma (PGNHL) is a distinct group of extranodal lymphomas with interesting geographical distribution and variable prevalence in different countries. We analysed epidemiological data of our patients with PGNHL in Primorsko-goranska County. Clinical data of 30 patients with PGNHL diagnosed and treated in Clinical Hospital Center of Rijeka, Croatia between January 1995 and December 2005 were prospectively analyzed. We used statistical analysis (t-test, chi2-test) for small groups. Out of 30 pts with PGNHL, 19 were born in Primorsko-goranska County, part of Croatia situated by the Adriatic sea which consists of three regions: City of Rijeka, Islands and Gorski Kotar. 6 of 19 patients (31.6%) were originally from Gorski Kotar which made incidence rate of PGNHL in Gorski Kotar 7 times higher than in other two regions. Many authors emphasized that relative frequency of PGNHL is very variable in various countries and regions. Geographical distribution of our patients was very surprising because Gorski Kotar is the region with lowest number of citizens, rural area without any known pollutants, and ecologically one of the most preserved microsystem in this part of Croatia. Gorski Kotar is known to be an endemic region for multiple sclerosis and lyme borreliosis. Is it for PGNHL too?  相似文献   
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