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1.
J Orthop Surg Res ; 16(1): 409, 2021 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-34174925

RESUMO

BACKGROUND: Percutaneous pinning fixation (PCP) has been used for the treatment of distal radius fractures for decades, especially in the elderly with fragile soft tissue. However, achieving and maintaining a sound anatomic reduction before PCP is difficult if we use the manipulative reduction method alone. Our study innovatively applied the Steinmann pin retractor for closed reduction combined with PCP, to provide a new protocol for the treatment of distal radius fractures. METHODS: From March 2017 to July 2018, 49 patients out of 57 that met the inclusion criteria but not the exclusion criteria were included in our retrospective cohort study. Sixteen patients were treated with Steinmann pin retractor-assisted closed reduction combined with PCP (S-PCP), and 19 patients were treated with the manipulative reduction combined with PCP (M-PCP), and 14 patients were treated with the manipulative reduction combined with cast splint (M-C). All these patients received a positive postoperative radiological and clinical evaluation. RESULTS: All the patients were followed up for a minimum of 2 years. The radiological parameters in each group improved significantly postoperative (posttreatment). In the S-PCP group, the values of radial height (postoperative, 13.33±1.74 mm; the first follow-up, 13.27±1.81mm; last follow-up, 13.16±1.76mm) and ulnar variance (postoperative, -0.10±1.29mm; the first follow-up, -0.05±1.27mm; last follow-up, -0.12±1.09mm) significantly improved as compared to the M-PCP and M-C groups. While the patients in the M-C group experienced significant re-displacement at the first and last follow-ups, in the S-PCP group, the range of wrist motion including extension (89.94±5.21%), radial deviation (90.69±6.01%), and supination (90.25±5.87%); ulnar deviation (89.81±5.82%) and QuickDASH score (2.70±3.64); and grip strength (92.50±5.59%), pronation (90.50±6.04%), and modified Mayo wrist score (90.94±4.17, the excellent rate reached up to 75%) also improved as compared to the M-PCP group, M-C group, or both groups at the last follow-up. CONCLUSION: S-PCP improves fracture reduction and wrist function and can serve as an effective method for A2(AO/OTA) and A3 type of distal radius fractures in the elderly with limited dorsal comminution, including intra-articular fractures with displacement less than 2mm.


Assuntos
Pinos Ortopédicos , Redução Fechada/instrumentação , Fixação Intramedular de Fraturas/instrumentação , Fraturas Intra-Articulares/cirurgia , Fraturas do Rádio/cirurgia , Idoso , Idoso de 80 Anos ou mais , Redução Fechada/métodos , Feminino , Fixação Intramedular de Fraturas/métodos , Consolidação da Fratura , Humanos , Fraturas Intra-Articulares/diagnóstico por imagem , Fraturas Intra-Articulares/fisiopatologia , Masculino , Pessoa de Meia-Idade , Radiografia , Rádio (Anatomia)/diagnóstico por imagem , Rádio (Anatomia)/fisiopatologia , Fraturas do Rádio/diagnóstico por imagem , Fraturas do Rádio/fisiopatologia , Estudos Retrospectivos , Contenções , Resultado do Tratamento
2.
Sci Bull (Beijing) ; 65(13): 1125-1136, 2020 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-36659164

RESUMO

Vegetation maps are important sources of information for biodiversity conservation, ecological studies, vegetation management and restoration, and national strategic decision making. The current Vegetation Map of China (1:1000000) was generated by a team of more than 250 scientists in an effort that lasted over 20 years starting in the 1980s. However, the vegetation distribution of China has experienced drastic changes during the rapid development of China in the last three decades, and it urgently needs to be updated to better represent the distribution of current vegetation types. Here, we describe the process of updating the Vegetation Map of China (1:1000000) generated in the 1980s using a "crowdsourcing-change detection-classification-expert knowledge" vegetation mapping strategy. A total of 203,024 field samples were collected, and 50 taxonomists were involved in the updating process. The resulting updated map has 12 vegetation type groups, 55 vegetation types/subtypes, and 866 vegetation formation/sub-formation types. The overall accuracy and kappa coefficient of the updated map are 64.8% and 0.52 at the vegetation type group level, 61% and 0.55 at the vegetation type/subtype level and 40% and 0.38 at the vegetation formation/sub-formation level. When compared to the original map, the updated map showed that 3.3 million km2 of vegetated areas of China have changed their vegetation type group during the past three decades due to anthropogenic activities and climatic change. We expect this updated map to benefit the understanding and management of China's terrestrial ecosystems.

3.
Huan Jing Ke Xue ; 39(6): 2953-2962, 2018 Jun 08.
Artigo em Chinês | MEDLINE | ID: mdl-29965655

RESUMO

Caohai wetland is a National Nature Reserve. Benthic animals were collected from the deep-water area in the middle of Caohai Lake and the shallow-water area in the surrounding marshes, and mercury and methyl mercury distributions in the benthic animals were analyzed and discussed. The risk of mercury pollution was evaluated. The concentrations of total mercury and methyl mercury in the benthonic animals were in the range of 0.51-46.55 ng·g-1 with an average of 7.82 ng·g-1 and 0.04-27.71 ng·g-1 with an average of 4.31 ng·g-1, respectively. This was lower than reports from other natural reserves. By contrast, the total mercury and methyl mercury in the benthic animals in summer were higher than in other seasons, which was consistent with the characteristics of methyl mercury distribution in sediments but opposite to the spatial distribution characteristics of total mercury in sediments. The methyl mercury contents in Cipangopaludina cathayensis were positively correlated with the content of methyl mercury in the sediments (r=0.52, P<0.05). The results showed methylation and the bioavailability of mercury in sediments from the shallow-water area were obviously higher than those from the deep-water area in the middle of Caohai Lake. The difference in organic matter content of the sediment or the wet-dry alternation (flooding-receding-flooding) in the surrounding shallow marshes was suspected to be associated with the obvious difference. The high enrichment coefficient of total mercury and methyl mercury in benthic animals were sufficient to raise the risk of mercury contamination in the aquatic food chain in the wetland.


Assuntos
Sedimentos Geológicos/química , Mercúrio/análise , Poluentes Químicos da Água/análise , Áreas Alagadas , Animais , China , Monitoramento Ambiental , Cadeia Alimentar
4.
PLoS One ; 10(9): e0136606, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26327118

RESUMO

Manganese (Mn) is an essential micronutrient needed for plant growth and development, but can be toxic to plants in excess amounts. However, some plant species have detoxification mechanisms that allow them to accumulate Mn to levels that are normally toxic, a phenomenon known as hyperaccumulation. These species are excellent candidates for developing a cost-effective remediation strategy for Mn-polluted soils. In this study, we identified a new passive Mn-hyperaccumulator Eucalyptus grandis × E. urophylla during a field survey in southern China in July 2010. This hybrid can accumulate as much as 13,549 mg/kg DW Mn in its leaves. Our results from Scanning Electron Microscope (SEM) X-ray microanalysis indicate that Mn is distributed in the entire leaf and stem cross-section, especially in photosynthetic palisade, spongy mesophyll tissue, and stem xylem vessels. Results from size-exclusion chromatography coupled with ICP-MS (Inductively coupled plasma mass spectrometry) lead us to speculate that Mn associates with relatively high molecular weight proteins and low molecular weight organic acids, including tartaric acid, to avoid Mn toxicity. Our results provide experimental evidence that both proteins and organic acids play important roles in Mn detoxification in Eucalyptus grandis × E. urophylla. The key characteristics of Eucalyptus grandis × E. urophylla are an increased Mn translocation facilitated by transpiration through the xylem to the leaves and further distribution throughout the leaf tissues. Moreover, the Mn-speciation profile obtained for the first time in different cellular organelles of Eucalyptus grandis × E. urophylla suggested that different organelles have differential accumulating abilities and unique mechanisms for Mn-detoxification.


Assuntos
Eucalyptus/metabolismo , Manganês/metabolismo , Folhas de Planta/metabolismo , Biodegradação Ambiental , Parede Celular/metabolismo , Cloroplastos/química , Microanálise por Sonda Eletrônica , Eucalyptus/química , Manganês/análise , Microscopia Eletrônica de Varredura , Folhas de Planta/química , Caules de Planta/química , Caules de Planta/metabolismo , Solo/química , Frações Subcelulares/química
5.
PLoS One ; 8(10): e77156, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24124605

RESUMO

The six species and three subspecies in the genus Chimarrogale (Soricomorpha: Soricidae) are commonly referred to as Asiatic water shrews. The Chimarrogale are the most widely distributed group of Nectogaline shrews, extending throughout the Oriental region and Japan. Because of the limited numbers of specimens available for study, the phylogenetic relationships and biogeographical history of this genus have not been comprehensively discussed. We used mitochondrial cytochrome b gene sequences to estimate phylogenetic relationships and divergence times among four Chimarrogale species, including all three subspecies of Chimarrogale himalayica. We also conducted a species delimitation analysis and tested two alternative migration scenarios in Asia through species distribution modeling and a reconstruction of the ancestral distribution. Here, we present the first proposed hypothesis regarding the Asiatic water shrew phylogeny and reveal ten putative species within the four recognized species. Distinct phylogenetic statuses of Chimarrogale phaeura, Chimarrogale platycephala, and Chimarrogale styani were confirmed. Chimarrogale himalayica was strongly supported as paraphyletic. We suggest that three subspecies of Chimarrogale himalayica should be reconsidered as distinct species. However, these suggestions must be considered with caution because only a single locus of a mtDNA gene was used. Four additional putative species, possibly distributed in central southwestern China and Taiwan, are currently undescribed; therefore, comprehensive morphological analyses are warranted to test their taxonomic statuses. The estimated molecular divergence times indicated that rapid speciation occurred during the early Pliocene, and current distribution patterns may have been affected by global cooling during the Pliocene/Pleistocene boundary. Reconstruction of the ancestral distribution and species distribution modeling for Asiatic water shrews revealed a low-latitude migration route over which ancestral Chimarrogale migrated from Europe via Central Asia to their current distribution. Our results demonstrated that Asiatic water shrews could have evolved throughout the low-latitude migration route from Europe to East and Southeast Asia.


Assuntos
DNA Mitocondrial , Filogenia , Musaranhos/classificação , Musaranhos/genética , Animais , Ásia , Biodiversidade , Clima , Citocromos b/genética , Ecossistema , Evolução Molecular , Geografia , Dinâmica Populacional
6.
Front Med ; 5(2): 208-11, 2011 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-21695627

RESUMO

Stressing the uniqueness and complexity of traditional Chinese medicine (TCM) theory system, this paper analyzes the characteristics of TCM as a discipline from four perspectives: scientific nature, fundamental theory, clinical practice, and pharmacological action. It suggests that when the research strategy of TCM theory is designed, the core theory of TCM should be emphasized on the theoretical research on TCM original thinking theory, TCM theory, Chinese materia medica and formulas, acupuncture and moxibustion, meridians and collaterals, and other related fields. Researchers and practitioners should ensure that the basic research on TCM theory is based on clinical practice, research methods (both traditional and contemporary) are exploited, and methodological innovation is underscored. The rule of TCM development should be followed and the characteristics and advantages of TCM carried forward. Meanwhile, the methods and theory of contemporary science and technology should be exploited to fulfill the goal of inheriting, enriching, and developing the fundamental theory of TCM.


Assuntos
Medicina Tradicional Chinesa/métodos , Filosofia Médica , Projetos de Pesquisa , China , Humanos
7.
Tree Physiol ; 31(4): 402-13, 2011 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-21470980

RESUMO

We selected six tree species, Pinus massoniana Lamb., Cryptomeria fortunei Hooibr. ex Otto et Dietr., Cunninghamia lanceolata (Lamb.) Hook., Liquidambar formosana Hance, Pinus armandii Franch. and Castanopsis chinensis Hance, which are widely distributed as dominant species in the forest of southern China where acid deposition is becoming more and more serious in recent years. We investigated the effects and potential interactions between simulated acid rain (SiAR) and three calcium (Ca) levels on seed germination, radicle length, seedling growth, chlorophyll content, photosynthesis and Ca content in leaves of these six species. We found that the six species showed different responses to SiAR and different Ca levels. Pinus armandii and C. chinensis were very tolerant to SiAR, whereas the others were more sensitive. The results of significant SiAR × Ca interactions on different physiological parameters of the six species demonstrate that additional Ca had a dramatic rescue effect on the seed germination and seedling growth for the sensitive species under SiAR. Altogether, we conclude that the negative effects of SiAR on seed germination, seedling growth and photosynthesis of the four sensitive species could be ameliorated by Ca addition. In contrast, the physiological processes of the two tolerant species were much less affected by both SiAR and Ca treatments. This conclusion implies that the degree of forest decline caused by long-term acid deposition may be attributed not only to the sensitivity of tree species to acid deposition, but also to the Ca level in the soil.


Assuntos
Chuva Ácida/efeitos adversos , Cálcio/farmacologia , Germinação/efeitos dos fármacos , Magnoliopsida/efeitos dos fármacos , Fotossíntese/efeitos dos fármacos , Traqueófitas/efeitos dos fármacos , Cálcio/análise , Cálcio/metabolismo , China , Clorofila/metabolismo , Magnoliopsida/crescimento & desenvolvimento , Magnoliopsida/metabolismo , Modelos Biológicos , Folhas de Planta/efeitos dos fármacos , Folhas de Planta/crescimento & desenvolvimento , Folhas de Planta/metabolismo , Plântula/efeitos dos fármacos , Plântula/crescimento & desenvolvimento , Plântula/metabolismo , Sementes/efeitos dos fármacos , Sementes/crescimento & desenvolvimento , Sementes/metabolismo , Solo/química , Especificidade da Espécie , Traqueófitas/crescimento & desenvolvimento , Traqueófitas/metabolismo , Árvores/efeitos dos fármacos , Árvores/crescimento & desenvolvimento , Árvores/metabolismo
8.
Environ Pollut ; 158(10): 3219-24, 2010 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-20702012

RESUMO

To assess the suitability of dendrochemistry as an indicator of soil acidification, soil chemistry and tree ring information of Abies fabri were measured at two distinct sites (severe acid deposition site-Emei Mountain and clean site-Gongga Mountain) of the subalpine forest ecosystems of western Sichuan, southwest China. The actual soil acidity (pH) was significantly correlated with some of the recent xylem cation (Ca, Mg, Mn, Al, Sr and Ba) concentrations and their molar ratios. Xylem Ca/Mg and Ca/Mn of A. fabri were ultimately selected to reconstruct the historical changes of soil pH in Emei Mountain and Gongga Mountain, respectively. The validity of those rebuild was also verified to a certain extent. We conclude that xylem cation molar ratios of A. fabri were superior to the single cation concentrations in soil acidity rebuild at the study sites due to normalizing for concentration fluctuations.


Assuntos
Abies/química , Ácidos/análise , Poluentes do Solo/análise , Solo/química , Xilema/química , Chuva Ácida , Cátions/análise , China , Ecossistema , Monitoramento Ambiental , Concentração de Íons de Hidrogênio , Árvores
9.
Environ Sci Technol ; 40(19): 5853-9, 2006 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-17051770

RESUMO

An alternative normalization method was developed for evaluating atmospheric polycyclic aromatic hydrocarbons (PAHs) pollution level when using tree bark as a passive sampling medium. Perylene (PER), which mainly stems from natural biogenic processes, was proposed as a "natural internal compound" (NIC) of atmospheric PAHs accumulation processes from air into the bark, and a concentration ratio of target PAH to PER (RPAH/PER) was used to minimize the uncertainty in the evaluation of atmospheric PAHs pollution level. Systematic investigation of the effects of intrinsic bark characteristics and extrinsic seasonal meteorological conditions on the partition processes of atmospheric PAHs indicated that RPAH/PER is as an alternative index as compared to bark mass concentration (BMCPAH, ng/g dry bark), lipid mass concentration (LMCPAH, ng/g lipid of bark), and area mass concentration (AMCPAH, ng/m2 surface area of bark) for the evaluation of atmospheric PAHs pollution and that it allows more flexible sampling of tree barks. Clearly, the methodology should be expected to be useful for the objective evaluation of atmospheric pollution levels of other persistent organic pollutants when using tree bark and other passive sampling media if corresponding NICs are found in the future.


Assuntos
Poluentes Atmosféricos/análise , Monitoramento Ambiental/métodos , Casca de Planta/química , Hidrocarbonetos Policíclicos Aromáticos/análise , Poluição do Ar/análise , Lipídeos/análise , Magnoliopsida , Chuva , Temperatura , Traqueófitas , Árvores
10.
J Zhejiang Univ Sci B ; 7(11): 849-57, 2006 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-17048297

RESUMO

Biomineralization of Si by plants into phytolith formation and precipitation of Si into clays during weathering are two important processes of silicon's biogeochemical cycle. As a silicon-accumulating plant, the widely distributed and woody Phyllostachys heterocycla var. pubescens (moso bamboo) contributes to storing silicon by biomineralization and, thus, prevents eutrophication of nearby waterbodies through silicon's erosion of soil particles.A study on the organic pool and biological cycle of silicon (Si) of the moso bamboo community was conducted in Wuyishan Biosphere Reserve, China. The results showed that: (1) the standing crop of the moso bamboo community was 13355.4 g/m2, of which 53.61%, 45.82% and 0.56% are represented by the aboveground and belowground parts of moso bamboos, and the understory plants, respectively; (2) the annual net primary production of the community was 2887.1 g/(m2 x a), among which the aboveground part, belowground part, litterfalls, and other fractions, accounted for 55.86%, 35.30%, 4.50% and 4.34%, respectively; (3) silicon concentration in stem, branch, leaf, base of stem, root, whip of bamboos, and other plants was 0.15%, 0.79%, 3.10%, 4.40%, 7.32%, 1.52% and 1.01%, respectively; (4) the total Si accumulated in the standing crop of moso bamboo community was 448.91 g/m2, with 99.83% of Si of the total community stored in moso bamboo populations; (5) within moso bamboo community, the annual uptake, retention, and return of Si were 95.75, 68.43, 27.32 g/(m2 x a), respectively; (6) the turnover time of Si, which is the time an average atom of Si remains in the soil before it is recycled into the trees or shrubs, was 16.4 years; (7) the enrichment ratio of Si in the moso bamboo community, which is the ratio of the mean concentration of nutrients in the net primary production to the mean concentration of nutrients in the biomass of a community, was 0.64; and lastly, (8) moso bamboo plants stored about 1.26x10(10) kg of silicon in the organic pool made up by the moso bamboo forests in the subtropical area of China.


Assuntos
Folhas de Planta/química , Raízes de Plantas/química , Caules de Planta/química , Poaceae/química , Silício/análise , Transporte Biológico , Biomassa , China , Ecossistema , Folhas de Planta/metabolismo , Raízes de Plantas/metabolismo , Caules de Planta/metabolismo , Poaceae/metabolismo , Silício/metabolismo
11.
Ying Yong Sheng Tai Xue Bao ; 16(2): 365-70, 2005 Feb.
Artigo em Chinês | MEDLINE | ID: mdl-15852940

RESUMO

Based on the analysis of characteristics of forest light environmental heterogeneity, this paper reviewed the research advance in the response of forest seedlings to light environmental heterogeneity from the aspects of photosynthesis, thermal dissipation, biomass accumulation and distribution, morphological traits, germination, and population dynamics, and discussed the ecological significance of different responses of seedling regeneration to light environmental heterogeneity in forest biodiversity maintenance, forest succession, and revegetation. Some suggestions for future research in this field were put forward.


Assuntos
Ecossistema , Plântula/crescimento & desenvolvimento , Luz Solar , Árvores/crescimento & desenvolvimento , Biodiversidade , Meio Ambiente , Fotossíntese
12.
Environ Sci Technol ; 38(18): 4739-44, 2004 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-15487781

RESUMO

Historical monitoring of airborne polycyclic aromatic hydrocarbons (PAHs) pollution levels was novelly demonstrated by analyzing the dated corks of a bark pocket formed from 1873 to 2003 in a Longpetiole Beech (Fagus longipetiolata) tree trunk sampled from southeastern China. The fundamental studies indicated that the PAHs of log K(oa) < 8.5 are primarily accumulated through interactions with lipid substances in cork and log K(oa) dependent, while the PAHs of log K(oa) > 8.5 existing as particle-phase dependent on log Vp are accumulated through stochastic entrapment by the lenticels on the surface of the cork. The translocation of PAHs by xylem flow and phloem stream as well as radial diffusion from the cork to the inner tissues was not significant, and the cork is most effective for accumulating airborne PAHs. The total concentrations of 16 EPA PAHs (sumPAHs) in the dated corks progressively increased from 43.5 ng/g recorded in the earliest available cork in 1873-1875 to the maximum 345.7 ng/g in 1956-1961, and then gradually decreased to 267.0 ng/g in 2003, while the concentration of perylene (PER) was slightly fluctuating at 0.178 +/- 0.033 ng/g. Moreover, the concentration ratio of sumPAHs to PER increased from 193 to 2431 from 1873 to 2003, indicating a progressive increase in PAH pollution in southeastern China.


Assuntos
Poluentes Atmosféricos/análise , Cinnamomum camphora/química , Monitoramento Ambiental/métodos , Fagus/química , Hidrocarbonetos Policíclicos Aromáticos/análise , Poluentes Atmosféricos/história , Poluentes Atmosféricos/isolamento & purificação , China , História do Século XIX , História do Século XX , História do Século XXI , Perileno/análise , Casca de Planta/química , Hidrocarbonetos Policíclicos Aromáticos/história , Hidrocarbonetos Policíclicos Aromáticos/isolamento & purificação
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