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排序方式: 共有98条查询结果,搜索用时 15 毫秒
11.
12.
Elisabeth APM Romme Piet Geusens Willem F Lems Erica PA Rutten Frank WJM Smeenk Joop PW van den Bergh Peter ThW van Hal Emiel FM Wouters 《Respiratory research》2015,16(1)
Although osteoporosis and its related fractures are common in patients with COPD, patients at high risk of fracture are poorly identified, and consequently, undertreated. Since there are no fracture prevention guidelines available that focus on COPD patients, we developed a clinical approach to improve the identification and treatment of COPD patients at high risk of fracture. We organised a round-table discussion with 8 clinical experts in the field of COPD and fracture prevention in the Netherlands in December 2013. The clinical experts presented a review of the literature on COPD, osteoporosis and fracture prevention. Based on the Dutch fracture prevention guideline, they developed a 5-step clinical approach for fracture prevention in COPD. Thereby, they took into account both classical risk factors for fracture (low body mass index, older age, personal and family history of fracture, immobility, smoking, alcohol intake, use of glucocorticoids and increased fall risk) and COPD-specific risk factors for fracture (severe airflow obstruction, pulmonary exacerbations and oxygen therapy). Severe COPD (defined as postbronchodilator FEV1 < 50% predicted) was added as COPD-specific risk factor to the list of classical risk factors for fracture. The 5-step clinical approach starts with case finding using clinical risk factors, followed by risk evaluation (dual energy X-ray absorptiometry and imaging of the spine), differential diagnosis, treatment and follow-up. This systematic clinical approach, which is evidence-based and easy-to-use in daily practice by pulmonologists, should contribute to optimise fracture prevention in COPD patients at high risk of fracture. 相似文献
13.
Usdin K; Chevret P; Catzeflis FM; Verona R; Furano AV 《Molecular biology and evolution》1995,12(1):73-82
The single most difficult problem in phylogenetic analysis is deciding
whether a shared taxonomic character is due to common ancestry or one that
appeared independently due to convergence, parallelism, or reversion to an
ancestral state. Mammalian L1 retrotransposons undergo periodic
amplifications in which multiple copies of the elements are interspersed in
the genome. Because these elements apparently are transmitted only by
inheritance and are retained in the genome, a shared L1 amplification event
can only be an inherited ancestral character. We propose that L1
amplification events can be an excellent tool for analyzing mammalian
evolution and demonstrate here how we addressed several refractory problems
in rodent systematics using L1 DNA as a taxonomic character.
相似文献
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15.
CTS Silva V. Wanderley-Teixeira FM Cunha JV Oliveira KA Dutra DMA Ferraz Navarro 《Biotechnic & histochemistry》2018,93(1):36-48
The armyworm, Spodoptera frugiperda, is the principal pest of corn in Brazil. Control is achieved primarily by synthetic insecticides, which cause problems for the agro-ecosystem. Alternative methods of control are under investigation and citronella (Cymbopogon winterianus) essential oil appears to be a promising agent. We investigated the effects of citronella oil using histological, histochemical and immunohistochemical methods. The midgut of larvae treated with citronella exhibited altered epithelium including cytoplasmic protrusions, columnar cell extrusion, pyknotic nuclei, and increased periodic acid-Schiff positive granules. Regenerative cells in the epithelium of the midgut increased in number, which facilitated subsequent regeneration of this tissue. After exposure to citronella, trophocytes, the principal cell type of the fat body, possessed enlarged vacuoles and mitotic bodies, and contained reduced amounts of glycogen, lipid, and protein. Citronella oil caused morphological changes of the midgut and reduction of stored resources in the fat body, which may adversely affect insect reproduction and survival. 相似文献
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17.
Sina Babazadeh Matthew L Broadhead John L Slavin Peter FM Choong 《International Seminars in Surgical Oncology : ISSO》2009,6(1):18
A presacral mass can present a diagnostic dilemma for the surgical oncologist. Differential diagnoses include congenital causes such as teratoma or chordoma, neurological causes such as neurilemoma or neurofibroma or other malignancies such as lymphoma or sarcoma. Diagnosis usually requires imaging such as CT and MRI and tissue biopsy. We present an unusual cause of a presacral mass being extramedullary haematopoiesis, found incidentally in a 71 year old female. Extramedullary haematopoiesis is defined as the production of myeloid and erythroid elements outside of the bone-marrow. This diagnosis is extremely rare in the presacral area especially in a patient with no haematological abnormalities. A review of the literature is presented. 相似文献
18.
Phylogenetic relationships of artiodactyls and cetaceans as deduced from the comparison of cytochrome b and 12S rRNA mitochondrial sequences 总被引:8,自引:0,他引:8
A data set of complete mitochondrial cytochrome b and 12S rDNA sequences is
presented here for 17 representatives of Artiodactyla and Cetacea, together
with potential outgroups (two Perissodactyla, two Carnivora, two
Tethytheria, four Rodentia, and two Marsupialia). We include seven
sequences not previously published from Hippopotamidae (Ancodonta) and
Camelidae (Tylopoda), yielding a total of nearly 2.1 kb for both genes
combined. Distance and parsimony analyses of each gene indicate that 11
clades are well supported, including the artiodactyl taxa Pecora,
Ruminantia (with low 12S rRNA support), Tylopoda, Suina, and Ancodonta, as
well as Cetacea, Perissodactyla, Carnivora, Tethytheria, Muridae, and
Caviomorpha. Neither the cytochrome b nor the 12S rDNA genes resolve the
relationships between these major clades. The combined analysis of the two
genes suggests a monophyletic Cetacea +Artiodactyla clade (defined as
"Cetartiodactyla"), whereas Perissodactyla, Carnivora, and Tethytheria fall
outside this clade. Perissodactyla could represent the sister taxon of
Cetartiodactyla, as deduced from resampling studies among outgroup
lineages. Cetartiodactyla includes five major lineages: Ruminantia,
Tylopoda, Suina, Ancodonta, and Cetacea, among which the phylogenetic
relationships are not resolved. Thus, Suiformes do not appear to be
monophyletic, justifying their split into the Suina and Ancodonta
infraorders. An association between Cetacea and Hippopotamidae is supported
by the cytochrome b gene but not by the 12S rRNA gene. Calculation of
divergence dates suggests that the Cetartiodactyla could have diverged from
other Ferungulata about 60 MYA.
相似文献
19.
20.
Kohei Hasegawa Yusuke Tsugawa Chu-Lin Tsai David FM Brown Carlos A Camargo Jr 《Respiratory research》2014,15(1):40