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401.
《Endocrine practice》2021,27(11):1093-1099
ObjectiveWe aimed to compare the thyroid ultrasound risk stratification systems (RSSs) of the American College of Radiology (ACR) Thyroid Imaging Reporting and Data System (TI-RADS), European TI-RADS, Korean TI-RADS, and American Thyroid Association (ATA), American Association of Clinical Endocrinologists, American College of Endocrinology, and Associazione Medici Endocrinologi guidelines to differentiate benign from malignant thyroid nodules and to avoid unnecessary fine needle aspiration (FNA).MethodsThe records of 1143 nodules ≥1 cm that underwent FNA biopsy and thyroidectomy between 2012 and 2020 at our institution were reviewed. Ultrasound categories and FNA recommendation indications of 5 international RSSs were compared with histopathological findings as benign or malignant. The ultrasound categories and recommended FNA indications, the proportion of the avoidable FNA procedures, and false negative rates (FNRs) by different systems were compared with each other.ResultsOf the 1143 nodules, 45% had thyroid malignancy. FNA recommendation and ultrasound risk classification of ATA guidelines had the highest area under curves of 0.619, and 0.715, respectively. ACR TI-RADS, American Association of Clinical Endocrinologists/American College of Endocrinology/Associazione Medici Endocrinologi guidelines, European TI-RADS, ATA guidelines, and Korean TI-RADS would have avoided FNA for 34.7%, 31%, 25.7%, 20%, and 6% of nodules with an FNR of 24%, 28.5%, 22%, 7.2%, and 1.9%, respectively.ConclusionOur findings showed that all RSSs classified the nodules appropriately for malignancy. ATA guidelines had the highest area under curves and a low FNR, whereas ACR TI-RADS would have spared more patients from FNA with a high FNR. 相似文献
402.
Morphogenesis induction and organogenic nodule differentiation in <Emphasis Type="Italic">Populus euphratica</Emphasis> Oliv. leaf explants 总被引:1,自引:1,他引:0
Sílvia Ferreira Dora Batista Susana Serrazina Maria Salomé Pais 《Plant Cell, Tissue and Organ Culture》2009,96(1):35-43
Populus euphratica Oliv. is a deciduous poplar species, occurring mainly in riparian areas of China and Middle Eastern countries, and presenting
high tolerance to extreme temperatures and high soil salinity. In this study, an optimized protocol for development and propagation
of P. euphratica from leaf explants is reported, based on a morphogenic process that involves organogenic nodule differentiation. Adventitious
shoot regeneration of P. euphratica from organogenic nodules of leaf explants was achieved within a range of concentrations of α-naphtalenacetic acid and 6-benzylaminopurine,
at a fixed 2:1 ratio. Cambial cells started to divide 5 days after inoculation on culture medium and, after 12 days, several
organizing centres were already formed. Non-friable callus tissue, together with organization centres, formed structures that
evolved to nodules after about 40 days which were, then, able to regenerate new shoots after 50–60 days. The nodules did not
separate from the mother explants and were able to successfully give rise to new adventitious shoots. These were rescued and
successfully grown and rooted in different culture media, and fully developed plants were obtained. The regeneration system
here described for P. euphratica is innovative, reproducible and data from histological studies of the morphogenic process support the classification of the
regenerative structures as organogenic nodules. 相似文献
403.
404.
Henryka Seliga 《Acta Physiologiae Plantarum》1999,21(4):427-431
Copper nutrition inhibited lipid peroxidation in root nodules of yellow lupin plants at the early growth stages by about 50
%. The antioxidative activity of copper in the process of lipid peroxidation could be associated with Cu taking part in oxidative
reaction of nodule catechol-like siderophores and its effect on iron accumulation and reactivity. The obtained results, for
the first time, suggest that the ability of copper to inhibit lipid peroxidation in nodules could be considered as a major
function for Cu requirements by symbiotic N2 fixation in grain legume nodules. 相似文献
405.
406.
407.
The cytokinin content of roots and nodules of pea and the culture supernatants from two strains of Rhizobium leguminosarum has been examined. Roots, nodules and wild-type Rhizobium culture medium contained very little cytokinin as indicated by bioassay. Chemical ionisation gas chromatography-mass spectrometric analysis of the isopentenyladenine content of the culture medium from the Rhizobium strains confirmed that the content of the wild-type was low (approx. 1 ng dm-3) but that it was increased by the introduction of the Agrobacterium Ti plasmid into the Rhizobium strain.Abbreviations CI
chemical ionisation
- GCMS
gas chromatography-mass spectrometry
- HPLC
high performance liquid chromatography
- iPAde
isopentenyladenine
- MIM
multiple ion monitoring 相似文献
408.
The main pathway of ammonia assimilation in the root nodules of Trigonella foenum-graecum is via nodule cytosol glutamine synthetase-glutamate synthase. 相似文献
409.
Sandy alluvial soils in a floodplain supporting a native stand ofCasuarina cunninghamiana Miq. produced about three times as many nodulated seedlings and more than twice as many nodules per nodulated seedling on roots of baitedCasuarina spp. than did clay loam red earth soils from the adjacent valley slope. Moist and well-aerated subsurficial alluvial sands had the greatest nodulation capacity of all the soils sampled. For all topographic positions, soil samples from depths greater than 20 cm promoted 76% more nodulated Casuarina seedlings than samples from the surficial 20 cm.Seedlings of three provenances ofC. cunninghamiana, together with seedlings ofC. glauca Sieb. ex Spreng.,C. cristata F. Muell ex Miq. andC. obesa Miq. developed significantly more nodules per pot and nodules per nodulated seedling in soils from this locale than seedlings of twoCasuarina equisetifolia Forst. provenances. Seedlings of two provenances ofAllocasuarina torulosa (Ait.) L. Johnson had fewer than 1% nodulated seedlings, a significantly lower level by far than that ofCasuarina seedlings.A. torulosa provenances also had significantly fewer nodulated seedlings per pot and nodules per nodulated seedling than all Casuarina hosts excepting one poorly-nodulated provenance ofC. equisetifolia.Nodulated seedlings of allCasuarina species had the capacity to fix atmospheric N2, as indicated by acetylene-reduction capability. The presence of yellow cladodes and low rates of acetylene reduction per plant forC. cristata Miq. suggest that this association was poorly effective. 相似文献
410.
The pilot study was undertaken to evaluate the role of FNA cytology in the clinical management of patients with thyroid swelling, in a District General Hospital (DGH) setting. One hundred and eleven patients were investigated over a period of 3 years, with a total of 142 fine needle aspirations. Statistical analysis showed a sensitivity of 71%, a specificity of 91% and a false negative rate of 2.7%. These results compare very favourably with other institutions. This study therefore shows that thyroid nodule FNA cytology can be performed in a DGH with a high standard of diagnostic accuracy, the results of which play a key role in patient management. 相似文献