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1.
目的:探讨非小细胞肺癌术后并发乳糜胸对患者生活质量的影响。方法:采用生活质量测定量表(QLQ-C30)回顾性分析第四军医大学唐都医院胸外科自2013年至2016年中收治的1015例肺癌手术患者的生活质量,发生乳糜胸组记为A组,未发生乳糜胸组记为B组。对比术前和术后1、3、6和12个月的生活质量有无统计学差异。结果:(1)术后1月时,除了社会功能、便秘、腹泻以外,两组生活质量指标评分均显著低于术前,且B组均显著低于A组,有统计学差异(表3,P0.05)。在手术后3月及以后逐渐恢复,至12月时,各组指标与术前基本相同(表3,P0.05);(2)两组术后生活质量相比较,术后1、3月,除社会功能、便秘、腹泻以外,其余生活质量功能指标B组均显著优于A组,有统计学差异(表3,P0.05)。在手术后6月及以后,B组所有指标与A组无统计学差异(表3,P0.05)。结论:肺癌根治术后发生乳糜胸患者生活质量显著低于未发生乳糜胸患者,因此应合理选择手术方式,注意术中操作,降低乳糜胸发生率,提高肺癌患者术后的生活质量。  相似文献   
2.
Although numerous studies have been conducted on the relationship between livelihood assets and strategies, only a few quantitative studies exist on the topic for anti-poverty policies with regard to the Tibetan Plateau. This study investigated 357 households in the upper reaches of the Dadu River watershed in the Eastern Tibetan Plateau, China, using the participatory rural appraisal method. Then, applying a multinomial logistic regression model, we quantitatively analyzed the relationship between livelihood assets and livelihood strategies, the findings of which have implications for local agricultural policy interventions. The preliminary results indicate that of the four classifications of livelihood strategies used in this study, the main livelihood strategy is that of the non-farming-dependent household type (i.e., Type III in our study) that combines agricultural and non-farm activities or practices self-employment for wages. There are significant differences in the livelihood assets owned by households with different livelihood strategies. Human, natural, and financial assets have significant influences on livelihood strategies, and the choice of livelihood strategy varies by livelihood assets. Further, with improvements in household labor capacity and cash income per capita, the livelihood strategies of non-agricultural and non-farming households may shift away from agriculture, while an increase in farmland cultivated per capita, cash income per capita, and household labor capacity may encourage households to adopt agriculture-dependent livelihood strategies. These findings contribute to research on livelihood and related development strategies and anti-poverty policies in not only the Eastern Tibetan Plateau but also other regions with similar livelihood strategies.  相似文献   
3.
Theory suggests that spatial structuring should select for intermediate levels of virulence in parasites, but empirical tests are rare and have never been conducted with castration (sterilizing) parasites. To test this theory in a natural landscape, we construct a spatially explicit model of the symbiosis between the ant-plant Cordia nodosa and its two, protecting ant symbionts, Allomerus and Azteca . Allomerus is also a castration parasite, preventing fruiting to increase colony fecundity. Limiting the dispersal of Allomerus and host plant selects for intermediate castration virulence. Increasing the frequency of the mutualist, Azteca , selects for higher castration virulence in Allomerus , because seeds from Azteca -inhabited plants are a public good that Allomerus exploits. These results are consistent with field observations and, to our knowledge, provide the first empirical evidence supporting the hypothesis that spatial structure can reduce castration virulence and the first such evidence in a natural landscape for either mortality or castration virulence.  相似文献   
4.
Cardiac stem cells are described in a number of mammalian species including humans. Cardiac stem cell clusters consisting of both lineage-negative and partially committed cells are generally identified between contracting cardiac myocytes. In the present study, c-kit+, Sca+, and Isl1+ stem cells were revealed to be located inside the sarcoplasm of cardiac myocytes in myocardial cell cultures derived from newborn, 20-, and 40-day-old rats. Intracellularly localized cardiac stem cells had a coating or capsule with a few pores that opened into the host cell sarcoplasm. The similar structures were also identified in the suspension of freshly isolated myocardial cells (ex vivo) of 20- and 40-day-old rats. The results from this study provide direct evidence for the replicative division of encapsulated stem cells, followed by their partial cardiomyogenic differentiation. The latter is substantiated by the release of multiple transient amplifying cells following the capsule rupture. In conclusion, functional cardiac stem cells can reside not only exterior to but also within cardiomyocytes.  相似文献   
5.
A new software package, RASPA, for simulating adsorption and diffusion of molecules in flexible nanoporous materials is presented. The code implements the latest state-of-the-art algorithms for molecular dynamics and Monte Carlo (MC) in various ensembles including symplectic/measure-preserving integrators, Ewald summation, configurational-bias MC, continuous fractional component MC, reactive MC and Baker's minimisation. We show example applications of RASPA in computing coexistence properties, adsorption isotherms for single and multiple components, self- and collective diffusivities, reaction systems and visualisation. The software is released under the GNU General Public License.  相似文献   
6.
目录     
《生态学杂志》2019,38(10):0
  相似文献   
7.
Faster running is not performed with proportional increase in all joint torque/work exertions. Although previous studies have investigated lumbopelvic kinetics for a single velocity, it is unclear whether each lumbopelvic torque should increase for faster running. We examined the relationship between running velocity and lumbopelvic kinetics. We calculated the three-dimensional lumbosacral kinetics of 10 male sprinters during steady-state running on a temporary indoor running track at five target velocities: 3.0 (3.20 ± 0.16), 4.5 (4.38 ± 0.18), 6.0 (5.69 ± 0.47), 7.5 (7.30 ± 0.41), and maximal sprinting (9.27 ± 0.36 m/s). The lumbosacral axial rotation torque increased more markedly (from 0.37 ± 0.06 to 1.99 ± 0.46 Nm/kg) than the extension and lateral flexion torques. The increase in the axial rotation torque was larger above 7.30 m/s. Conversely, the extension and lateral flexion torques plateaued when running velocity increased above 7.30 m/s. Similar results were observed for mechanical work. The results indicate that faster running required larger lumbosacral axial rotation torque. Conversely, the extension and lateral flexion torques were relatively invariant to running velocity above 7 m/s, implying that faster running below 7 m/s might increase the biomechanical loads causing excessive pelvic posterior tilt and excessive pelvic drop which has the potential to cause pain/injury related to lumbopelvic extensors and lateral flexors, whereas these biomechanical loads might not relate with running velocity above 7 m/s.  相似文献   
8.
建立一种靶点蛋白质快速定量检测方法。在原有侧向流动免疫层析技术的基础上,通过优化层析材料和纳米微球的均一性、改进检测区的检测方法,经逐点扫描技术,建立标准浓度曲线,以达到对临床靶点蛋白质的定量检测。以乳腺癌组织中的Her2表达为例,通过对已知浓度样品的检测,验证本技术方法的准确度大于96%。另外,以蛋白质免疫印迹作为组织中特定蛋白质检测金标准,分析临床肿瘤组织中Her2蛋白的含量,其准确率也达到95.5%,而免疫组织化学方法检测准确率仅为69.58%。新型免疫层析法检测结果与靶向治疗患者的愈后密切相关(P<0.01)。改进后的新型免疫层析方法能够准确地对临床靶点蛋白质进行定量检测,而且结合侧向流动技术的简单、快速和易用性,这种新型检测方法可以广泛应用于临床组织标本、血液标本和体液标本中靶点蛋白质的临场定量检测,在一定程度上可以替代免疫组化技术。  相似文献   
9.
Spherical and cylindrical water droplets on silicon surface are studied to tune the silicon–oxygen interaction. We use molecular dynamics simulations to estimate the contact angle of two different shaped droplets. We found that the cylindrical droplets are independent of the line tension as their three phases curvature is equal zero. Additionally, we compare an analytical model, taking into account or not the Tolman length and we show that for spherical small size droplets, this length is important to be included, in contrast to cylindrical droplets in which the influence of the Tolman length is negligible. We demonstrate that the usual convenient way to exclude linear tension in the general case can give wrong results. Here, we consider cylindrical droplets, since their contact angle does not depend on the droplet size in the range of few to 10ths of nanometres. The droplets are stabilised due to the periodic boundary conditions. This allows us to propose a new parameterisation for nanoscale droplets, which is independent the size of the droplets or its shape, minimising at the same time the calculation procedure. With the proposed methodology, we can extract the epsilon parameter of the interaction potential between a liquid and a solid from the nanoscaled molecular simulation with only as input the macrosized experimental wetting angle for a given temperature.  相似文献   
10.
Butana and Kenana breeds from Sudan are part of the East African zebu Bos indicus type of cattle. Unlike other indigenous zebu cattle in Africa, they are unique due to their reputation for high milk production and are regarded as dairy cattle, the only ones of their kind on the African continent. In this study, we sequenced the complete mitochondrial DNA (mtDNA) D‐loop of 70 animals to understand the maternal genetic variation, demographic profiles and history of the two breeds in relation to the history of cattle pastoralism on the African continent. Only taurine mtDNA sequences were identified. We found very high mtDNA diversity but low level of maternal genetic structure within and between the two breeds. Bayesian coalescent‐based analysis revealed different historical and demographic profiles for the two breeds, with an earlier population expansion in the Butana vis a vis the Kenana. The maternal ancestral populations of the two breeds may have diverged prior to their introduction into the African continent, with first the arrival of the ancestral Butana population. We also reveal distinct demographic history between the two breeds with the Butana showing a decline in its effective population size (Ne) in the recent past ~590 years. Our results provide new insights on the early history of cattle pastoralism in Sudan indicative of a large ancient effective population size.  相似文献   
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