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91.
Value of video-assisted thoracoscopic surgery in the diagnosis and treatment of pulmonary tuberculoma: 53 cases analysis and review of literature
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Tuberculoma of the lung is one of manifestations in tuberculosis and usually presents as a solitary pulmonary nodule (SPN). It is difficult to differentiate tuberculoma from SPN by other benign or malignant diseases. At present, the crucial role of video-assisted thoracoscopic surgery (VATS) in diagnosis and treatment of pulmonary diseases has been well acknowledged. Here, we reported 53 patients undergoing VATS resection for tuberculomas in our series. No postoperative mortality was found and only two patients experienced prolonged air-leakage (>7 d) and two had minor wound infections that were recovered after anti-tuberculosis or antibiotic treatment. Anti-tuberculosis chemotherapy from 6 to 12 months was routinely used postoperatively. We conclude that VATS is a satisfactory tool for the diagnosis and treatment of tuberculoma and can also establish a reliable diagnosis for all patients with SPNs. 相似文献
92.
台湾可持续能源发展指标建构与耦合性分析 总被引:1,自引:0,他引:1
为应对全球气候变迁之冲击,以及迈向低碳社会,推动可持续能源发展,已成为本世纪各国政府施政的重点.依据国际可持续能源指标架构,建立"台湾可持续能源指标系统",并以Eview计量软件进行指标项目与架构之"单根"(unit root)、"共整合"(integration)、与"因果"(causality)检定,并据此建构的长期稳定关系与各方面耦合性(coupling)的可持续能源发展指标"压力-状态-响应"(Pressure,State,Response,PSR)架构系统.回顾了台湾近18年(1990-2007)来可持续能源发展绩效,获得结论如下:1)台湾能源发展已朝向可持续性,其中以环境保护方面绩效最佳,而能源安全与经济竞争力仍需改善;2)整体指标架构的状态与响应指标耦合度相当高,惟压力指标则呈现脱钩(decoupling)现象;3)权重模拟分析发现,适当调整权重,可以大幅提高经济竞争力与环境保障方面指标耦合性,显示权重具敏感性;惟能源安全指标方面的权重较不具敏感性. 相似文献
93.
94.
Als TD Vila R Kandul NP Nash DR Yen SH Hsu YF Mignault AA Boomsma JJ Pierce NE 《Nature》2004,432(7015):386-390
Large blue (Maculinea) butterflies are highly endangered throughout the Palaearctic region, and have been the focus of intense conservation research. In addition, their extraordinary parasitic lifestyles make them ideal for studies of life history evolution. Early instars consume flower buds of specific host plants, but later instars live in ant nests where they either devour the brood (predators), or are fed mouth-to-mouth by the adult ants (cuckoos). Here we present the phylogeny for the group, which shows that it is a monophyletic clade nested within Phengaris, a rare Oriental genus whose species have similar life histories. Cuckoo species are likely to have evolved from predatory ancestors. As early as five million years ago, two Maculinea clades diverged, leading to the different parasitic strategies seen in the genus today. Contrary to current belief, the two recognized cuckoo species show little genetic divergence and are probably a single ecologically differentiated species. On the other hand, some of the predatory morphospecies exhibit considerable genetic divergence and may contain cryptic species. These findings have important implications for conservation and reintroduction efforts. 相似文献
95.
The protein kinase PKR is required for macrophage apoptosis after activation of Toll-like receptor 4 总被引:1,自引:0,他引:1
Hsu LC Park JM Zhang K Luo JL Maeda S Kaufman RJ Eckmann L Guiney DG Karin M 《Nature》2004,428(6980):341-345
Macrophages are pivotal constituents of the innate immune system, vital for recognition and elimination of microbial pathogens. Macrophages use Toll-like receptors (TLRs) to detect pathogen-associated molecular patterns--including bacterial cell wall components, such as lipopolysaccharide or lipoteichoic acid, and viral nucleic acids, such as double-stranded (ds)RNA--and in turn activate effector functions, including anti-apoptotic signalling pathways. Certain pathogens, however, such as Salmonella spp., Shigellae spp. and Yersiniae spp., use specialized virulence factors to overcome these protective responses and induce macrophage apoptosis. We found that the anthrax bacterium, Bacillus anthracis, selectively induces apoptosis of activated macrophages through its lethal toxin, which prevents activation of the anti-apoptotic p38 mitogen-activated protein kinase. We now demonstrate that macrophage apoptosis by three different bacterial pathogens depends on activation of TLR4. Dissection of anti- and pro-apoptotic signalling events triggered by TLR4 identified the dsRNA responsive protein kinase PKR as a critical mediator of pathogen-induced macrophage apoptosis. The pro-apoptotic actions of PKR are mediated both through inhibition of protein synthesis and activation of interferon response factor 3. 相似文献
96.
97.
Functional link between ataxia-telangiectasia and Nijmegen breakage syndrome gene products 总被引:50,自引:0,他引:50
Zhao S Weng YC Yuan SS Lin YT Hsu HC Lin SC Gerbino E Song MH Zdzienicka MZ Gatti RA Shay JW Ziv Y Shiloh Y Lee EY 《Nature》2000,405(6785):473-477
Ataxia-telangiectasia (A-T) and Nijmegen breakage syndrome (NBS) are recessive genetic disorders with susceptibility to cancer and similar cellular phenotypes. The protein product of the gene responsible for A-T, designated ATM, is a member of a family of kinases characterized by a carboxy-terminal phosphatidylinositol 3-kinase-like domain. The NBS1 protein is specifically mutated in patients with Nijmegen breakage syndrome and forms a complex with the DNA repair proteins Rad50 and Mrel1. Here we show that phosphorylation of NBS1, induced by ionizing radiation, requires catalytically active ATM. Complexes containing ATM and NBS1 exist in vivo in both untreated cells and cells treated with ionizing radiation. We have identified two residues of NBS1, Ser 278 and Ser 343 that are phosphorylated in vitro by ATM and whose modification in vivo is essential for the cellular response to DNA damage. This response includes S-phase checkpoint activation, formation of the NBS1/Mrel1/Rad50 nuclear foci and rescue of hypersensitivity to ionizing radiation. Together, these results demonstrate a biochemical link between cell-cycle checkpoints activated by DNA damage and DNA repair in two genetic diseases with overlapping phenotypes. 相似文献
98.
ZHOU HuaiChun HUANG ZhiFeng CHENG Qiang LU We QIU Kui CHEN Chen HSU Pei-feng 《科学通报(英文版)》2011,56(10):962-968
The inferior mirage from road surfaces is a common phenomenon, which can be easily seen in everyday life. It has been recognized
in the literature as a light refraction phenomenon due to the refractive index gradient caused by the temperature gradient
in the air strata above the road surfaces. However, it was also suggested that the mirage is just a phenomenon of specular
reflection at grazing incidence. Because of the lack of reasonable and quantitative evidence, the generally accepted light
refraction theory has not yet been refuted. Here we show some mirror-like reflection images captured from a road surface stretch
in Yujiashan North Road, Wuhan, China, when there was no obvious temperature gradient on or above the road, measured on a
winter day in December 2009. This provided direct evidence to doubt the temperature induced light refraction mechanism of
the inferior mirage. Furthermore, the critical grazing angle of about 0.2° to the road plane where the mirror-like reflection
appears could not make the rough surface scatter incident light as a smooth surface according to the Rayleigh criterion. Therefore
the phenomenon is a mirrorlike observation effect of scattering from the surface, which cannot be entirely explained by light
refraction via air strata. The results demonstrate that the image-formation mechanism and the observer-based-analysis method
shown here potentially offer a means of understanding a wide range of scattering phenomena from rough surfaces at grazing
angle; for example, the superior mirages of unusual brightness occasionally observed over frozen lakes and the off-specular
reflection phenomenon. 相似文献
99.
Specificity in Toll-like receptor signalling through distinct effector functions of TRAF3 and TRAF6 总被引:1,自引:0,他引:1
Häcker H Redecke V Blagoev B Kratchmarova I Hsu LC Wang GG Kamps MP Raz E Wagner H Häcker G Mann M Karin M 《Nature》2006,439(7073):204-207
Toll-like receptors (TLRs) are activated by pathogen-associated molecular patterns to induce innate immune responses and production of pro-inflammatory cytokines, interferons and anti-inflammatory cytokines. TLRs activate downstream effectors through adaptors that contain Toll/interleukin-1 receptor (TIR) domains, but the mechanisms accounting for diversification of TLR effector functions are unclear. To dissect biochemically TLR signalling, we established a system for isolating signalling complexes assembled by dimerized adaptors. Using MyD88 as a prototypical adaptor, we identified TNF receptor-associated factor 3 (TRAF3) as a new component of TIR signalling complexes that is recruited along with TRAF6. Using myeloid cells from TRAF3- and TRAF6-deficient mice, we show that TRAF3 is essential for the induction of type I interferons (IFN) and the anti-inflammatory cytokine interleukin-10 (IL-10), but is dispensable for expression of pro-inflammatory cytokines. In fact, TRAF3-deficient cells overproduce pro-inflammatory cytokines owing to defective IL-10 production. Despite their structural similarity, the functions of TRAF3 and TRAF6 are largely distinct. TRAF3 is also recruited to the adaptor TRIF (Toll/IL-1 receptor domain-containing adaptor-inducing IFN-beta) and is required for marshalling the protein kinase TBK1 (also called NAK) into TIR signalling complexes, thereby explaining its unique role in activation of the IFN response. 相似文献
100.
LI Kai Way CHEN Chin Jung LIN Ching-Hua HSU Yao Wen 《清华大学学报》2006,11(6):712-719
Introduction Slips and falls are common phenomena both in work- places and leisure activities. The coefficient of fric- tion (COF) between footwear and the floor is regarded as the most critical item determining the occurrence of a slip. It is commonly ac… 相似文献