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891.
Sina Jasim Kepal N. Patel Gregory Randolph Stephanie Adams Roberto Cesareo Edward Condon Tara Henrichsen Malak Itani Maria Papaleontiou Leonardo Rangel John Schmitz Marius N. Stan 《Endocrine practice》2022,28(4):433-448
ObjectiveThe objective of this disease state clinical review is to provide clinicians with a summary of the nonsurgical, minimally invasive approaches to managing thyroid nodules/malignancy, including their indications, efficacy, side effects, and outcomes.MethodsA literature search was conducted using PubMed and appropriate key words. Relevant publications on minimally invasive thyroid techniques were used to create this clinical review.ResultsMinimally invasive thyroid techniques are effective and safe when performed by experienced centers. To date, percutaneous ethanol injection therapy is recommended for recurrent benign thyroid cysts. Both ultrasound-guided laser and radiofrequency ablation can be safely used for symptomatic solid nodules, both toxic and nontoxic. Microwave ablation and high-intensity focused ultrasound are newer approaches that need further clinical evaluation. Despite limited data, encouraging results suggest that minimally invasive techniques can also be used in small-size primary and locally recurrent thyroid cancer.ConclusionSurgery and radioiodine treatment remain the conventional and established treatments for nodular goiters. However, the new image-guided minimally invasive approaches appear safe and effective alternatives when used appropriately and by trained professionals to treat symptomatic or enlarging thyroid masses. 相似文献
892.
893.
894.
Mediterranean countries like Portugal and Spain, so far characterised by extensive traditional land use over major parts of
their territories, have been less affected by species losses. However, they are facing severe changes. As a model organism
we chose the butterfly Euphydryas aurinia, highly threatened in Central Europe but still common at the Iberian Peninsula, for a mark-release-recapture survey in the
western Algarve. We examined key factors for stabile metapopulation systems to assess the ability of long-term survival in
the increasingly fragmented landscapes of the Iberian Peninsula. The density of the examined population was high (ca. 2,200
individuals/ha). However, the MRR-based proportion of individuals moving longer distance classes showed a better fit to the
negative exponential function than to the inverse power function implying restricted dispersal behaviour. The orientation
pattern of short distance movements (<10 m) proved to be independent from habitat structures. In contrast, longer movements
(>10 m) were strongly orientated along the main habitat axes revealing the importance of internal habitat structures for the
orientation of dispersing individuals. Based on these data, we discuss the severe consequences for the fauna of the Iberian
Peninsula in an increasingly fragmented and monotonous landscape. 相似文献
895.
Patrick Slama Jean-Luc Boucher Marius Réglier 《Journal of inorganic biochemistry》2009,103(3):455-462
N-Aryl-N′-hydroxyguanidines are compounds that display interesting pharmacological properties but their chemical reactivity remains poorly investigated. Some of these compounds are substrates for the heme-containing enzymes nitric-oxide synthases (NOS) and act as reducing co-substrates for the copper-containing enzyme Dopamine β-Hydroxylase (DBH) [P. Slama, J.L. Boucher, M. Réglier, Biochem. Biophys. Res. Commun. 316 (2004) 1081-1087]. DBH catalyses the hydroxylation of the important neurotransmitter dopamine into norepinephrine in the presence of both molecular oxygen and a reducing co-substrate. Although many molecules have been used as co-substrates for DBH, their interaction at the active site of DBH and their role in mechanism are not clearly characterized. In the present paper, we have used a water-soluble copper-N3S complex that mimics the CuB site of DBH, and aromatic N-hydroxyguanidines as reducers to address this question. N-Aryl-N′-hydroxyguanidines readily reduced copper(II) to Cu(I) and were oxidized into a nitrosoamidine as previously observed in reactions performed with purified DBH. These data describe for the first time the reactivity of N-aryl-N′-hydroxyguanidines with a water-soluble copper(II) complex and help to understand the interaction of co-substrates with copper at the active site of DBH. 相似文献
896.
897.
Edgar Brunner Arne C. Bathke Marius Placzek 《Biometrical journal. Biometrische Zeitschrift》2012,54(3):301-316
We present new inference methods for the analysis of low‐ and high‐dimensional repeated measures data from two‐sample designs that may be unbalanced, the number of repeated measures per subject may be larger than the number of subjects, covariance matrices are not assumed to be spherical, and they can differ between the two samples. In comparison, we demonstrate how crucial it is for the popular Huynh‐Feldt (HF) method to make the restrictive and often unrealistic or unjustifiable assumption of equal covariance matrices. The new method is shown to maintain desired α‐levels better than the well‐known HF correction, as demonstrated in several simulation studies. The proposed test gains power when the number of repeated measures is increased in a manner that is consistent with the alternative. Thus, even increasing the number of measurements on the same subject may lead to an increase in power. Application of the new method is illustrated in detail, using two different real data sets. In one of them, the number of repeated measures per subject is smaller than the sample size, while in the other one, it is larger. 相似文献
898.
899.
Roderic E. Bosboom Guillaume Dupont-Nivet Alexander J.P. Houben Henk Brinkhuis Giuliana Villa Oleg Mandic Marius Stoica Willem Jan Zachariasse ZhaoJie Guo ChuanXin Li Wout Krijgsman 《Palaeogeography, Palaeoclimatology, Palaeoecology》2011,299(3-4):385-398
The Paleogene sediments of the southwest Tarim Basin along the West Kunlun Shan in western China include the remnants of the easternmost extent of a large epicontinental sea. This shallow sea once extended across the Eurasian continent before it retreated westward and eventually separated as the Paratethys Sea. Climate modeling results suggest that this sea retreat is an equally important forcing mechanism as the Tibetan plateau uplift in the aridification of the Asian continental interior and the intensification of the Asian monsoon system. The age and paleogeography of the retreat are poorly constrained, hindering the understanding of its cause and paleoenvironmental impacts. This study reports litho- and biostratigraphic results from two sections recording the last major regression out of the Tarim Basin that is expressed by a regional transition from marine clastics and limestones to continental red-beds. Rich micro- and macrofossil assemblages, including benthic foraminifera, ostracods, bivalves, calcareous nannofossils and organic walled dinoflagellate cysts (dinocysts), indicate a shallow, proximal and marine environment. Strong similarity to assemblages known from Central Asia and Europe confirms that surface–ocean connections extended across Eurasia from the Tarim Basin to the western Tethys during the latest Eocene. Moreover, the recovered fossil associations date the last marine sediments as earliest Priabonian in age (~ 37 Ma; overlap between dinoflagellate Mps Interval Zone and calcareous nannofossil Zone CP 14). The retreat of the sea from the Tarim Basin is time-equivalent with the sea level lowstand at the Bartonian–Priabonian boundary but pre-dates both the Oligocene–Miocene regional uplift of the Pamir mountains and Kunlun Shan and the major eustatic sea-level falls of the Eocene–Oligocene Transition (~ 34 Ma) and mid-Oligocene (~ 30 Ma), which are usually held responsible for the sea retreat. Furthermore, a concomitant and significant aridification step occurs at ~ 36.6 Ma (top of chron C17n.1n) as recorded by regional sedimentary records of the Xining Basin along the northeastern Tibetan Plateau, suggesting that the Tarim Sea served as a significant moisture contributor for the Asian interior. 相似文献
900.
A Klein J Branny M Sudol M Knycz C Drózd A Szuro 《Folia histochemica et cytochemica》1979,17(4):353-362
The non-dialysable sugar-peptide rich fraction of bovine blood plasma has been studied with regard to its influence on the amino acid incorporation of BHK-21 and BHK/RSV cells in vitro. The results indicate that the Nsp fraction contains a peptide factor(s) causing changes in activity for the protein and DNA synthethizing system in both the cell cultures examined. The biological activity of the factor(s) is regulated by interaction with blood serum components and this fact may play a leading role in its regulatory function. 相似文献