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101.
Luis Uriel Gonzalez-Avila Miguel Angel Loyola-Cruz Cecilia Hernndez-Cortez Juan Manuel Bello-Lpez Graciela Castro-Escarpulli 《International journal of molecular sciences》2021,22(11)
The increase in the use of antimicrobials such as colistin for the treatment of infectious diseases has led to the appearance of Aeromonas strains resistant to this drug. However, resistance to colistin not only occurs in the clinical area but has also been determined in Aeromonas isolates from the environment or animals, which has been determined by the detection of mcr genes that confer a resistance mechanism to colistin. The variants mcr-1, mcr-3, and mcr-5 have been detected in the genus Aeromonas in animal, environmental, and human fluids samples. In this article, an overview of the resistance to colistin in Aeromonas is shown, as well as the generalities of this molecule and the recommended methods to determine colistin resistance to be used in some of the genus Aeromonas. 相似文献
102.
103.
Radiologic errors continue to be made at a rate that has changed little over the past 50 years, despite a variety of methods that have been proposed to reduce such errors. Many of these methods, as well as other steps that can be taken to decrease errors, are described elsewhere [6, 31, 32]. However, the question of whether a missed radiographic diagnosis constitutes malpractice has confounded radiologists, patients, referring physicians, attorneys, jurors, and judges for decades, and it is not likely that the question will be resolved to the satisfaction of any of these parties in the foreseeable future. Against this backdrop, radiologists continue to be subjected to malpractice litigation more for missing radiographic diagnoses than for any other reason. Moreover, radiologists who are sued for missing diagnoses are likely to have more indemnification paid on their behalf to satisfy a settlement or adverse jury verdict than for any other malpractice allegation. Assuredly, it is difficult to defend a radiologist who has failed to perceive a radiographic abnormality that in retrospect can be readily perceived by medical and nonmedical observers alike. Nonetheless, solid defense-supporting data are available that, at times, can be presented to a jury successfully to achieve vindication for a defendant radiologist. These data include statistics regarding the frequency of errors committed by radiologists and other physicians during the course of ordinary everyday practice, the factors that cause varying conspicuity of radiographic densities, the limitations of normal human visual perception, and evidence that the process by which the radiologist originally rendered the interpretation was free of deficiency. 相似文献
104.
105.
Histopathologic studies have demonstrated microshards from silicone elastomer metatarsophalangeal joint implants in adjacent tissues in a setting of chronic inflammation and in inguinal lymph nodes. Cytologic smears of synovial fluid from symptomatic implanted joints should show these refractile, nonpolarizing microshards in the reactive inflammatory context. Nonspecific enzymatic inflammatory activity contributes to further destabilization of the implants, eventuating in symptoms and signs requiring prosthesis removal. Cytopathologic examination of aspirated fluid from the vicinity of a symptomatic implanted joint demonstrates foreign body reaction to silicone elastomer, predicting a need for intervention before the local damage is severe and disabling. 相似文献
106.
Karl S. Minsker Vadim P. Zakharov Alexander Al. Berlin Gennadi E. Zaikov 《应用聚合物科学杂志》2004,94(2):613-624
Investigations on development of a macrokinetics approach were generalized to the analysis of fast chemical reactions, mainly using cationic polymerization of isobutylene as an example, which is a new class of liquid‐phase processes. The removal of diffusional constraints on polymer synthesis, by intensification of turbulent mixing in the reaction zone, makes it possible to calculate the kinetic parameters of polymerization and polymer‐analogous reactions, to optimize the molecular characteristics of polymeric products obtained, and to control the character of the process as a whole. The laws pertaining to the progression of fast processes are considered for the synthesis of separate polymers, in particular stereoregular polydienes, ethylene–propylene copolymers, and chlorobutyl rubber. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 94: 613–624, 2004 相似文献
107.
108.
In Machiavelli's theory of power, the concept of ‘divide and rule’ forms the main theme: the ruler has absolute power and to maintain and increase such power all means are justified. When viewed against the background of this theory, the current debate in the Netherlands on the unbundling of energy (electricity, gas) companies can be observed as an example of ‘divide and rule’, in which the Dutch Minister of Economic Affairs plays a central role. Yet, contrary to Machiavelli in his time, the Dutch government does, in fact, aim principally at the greater welfare of the Dutch people. It is therefore noteworthy that, while important steps in the decision to unbundled have been taken, there is no evidence that the Dutch people will indeed benefit from the envisaged unbundling. 相似文献
109.
Garcia-Rudaz C Dorfman M Nagalla S Svechnikov K Söder O Ojeda SR Dissen GA 《Reproduction (Cambridge, England)》2011,142(2):319-331
Excessive nerve growth factor (NGF) production by the ovary, achieved via a transgenic approach, results in arrested antral follicle growth, reduced ovulatory capacity, and a predisposition to cyst formation in response to mildly elevated LH levels. Two salient features in these mutant mice (termed 17NF) are an elevated production of 17α-hydroxyprogesterone (17-OHP(4)), testosterone, and estradiol (E(2)) in response to gonadotropins, and an increased frequency of granulosa cell (GC) apoptosis. In this study, we show that the increase in steroidal response is associated with enhanced expression of Cyp17a1, Hsd17b, and Cyp19a1, which encode the enzymes catalyzing the synthesis of 17-OHP(4), testosterone, and E(2) respectively. Using a proteomic approach, we identified stathmin (STMN1), as a protein that is overproduced in 17NF ovaries. In its phosphorylated state, STMN1 mediates a cell death signal initiated by tumor necrosis factor α (TNF). STMN1 is expressed in GCs and excessive NGF increases its abundance as well as that of its forms phosphorylated at serine (Ser) 16, 25, and 38. TNF synthesis is also increased in 17NF ovaries, and this change is abolished by blocking neurotrophic tyrosine kinase receptors. Inhibiting TNF actions in vivo by administering a soluble TNF receptor prevented the increase in total and phosphorylated STMN1 production, as well as GC apoptosis in NGF-overproducing ovaries. These results indicate that an excess of NGF in the ovary promotes steroidogenesis by enhancing the expression of enzyme genes involved in 17-OHP(4), testosterone, and E(2) synthesis, and causes GC apoptosis by activating a TNF/ STMN1-mediated cell death pathway. 相似文献
110.
Honsell G De Bortoli M Boscolo S Dell'Aversano C Battocchi C Fontanive G Penna A Berti F Sosa S Yasumoto T Ciminiello P Poli M Tubaro A 《Environmental science & technology》2011,45(16):7051-7059
Ostreopsis cf. ovata, a benthic dinoflagellate often blooming along the Mediterranean coasts, has been associated with toxic events ranging from dyspnea to mild dermatitis. In late September 2009, an Ostreopsis cf. ovata bloom occurred in the Gulf of Trieste (Northern Adriatic Sea; Italy), causing pruritus and mild dermatitis in beachgoers. An integrated study was initiated to characterize Ostreopsis cells by light and confocal microscopy, PCR techniques, immunocytochemistry, and high resolution liquid chromatography-mass spectrometry (HR LC-MS). The presence of Ostreopsis cf. ovata of the Atlantic/Mediterranean clade was unambiguously established by morphological and genetic analyses in field samples. Several palytoxin-like compounds (ovatoxin-a,-b,-c,-d,-e) were identified by HR LC-MS, ovatoxin-a being the most abundant (45-64 pg/cell). Surprisingly, no palytoxin was detected. For the first time, monoclonal and polyclonal antipalytoxin antibodies revealed the intracellular cytoplasmic localization of ovatoxins, suggesting their cross-reactivity with these antibodies. Since harmful dinoflagellates do not always produce toxins, the immunocytochemical localization of ovatoxins, although qualitative, can provide an early warning for toxic Ostreopsis cells before their massive diffusion and/or concentration in seafood. 相似文献