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191.
Javier Gallego-Plazas Francisco Menarguez-Pina Natividad Martinez-Banaclocha Vanesa Pons-Sanz Fernando Mingol-Navarro Jose A Ruiz-Macia Sonia Macia-Escalante 《International Seminars in Surgical Oncology : ISSO》2008,5(1):18
We present a case of locally advanced rectal cancer with initial optimal local control after neoadjuvant concurrent chemoradiotherapy followed by surgery; early liver recurrence then occurred and was treated again with curative intent with neoadjuvant combination chemotherapy followed by liver surgery. We reflect on this difficult problem and discuss relevant topics to this case report. 相似文献
192.
Eva E. A. Vila Mireya Snchez-Garza Jesús Caldern 《The Journal of eukaryotic microbiology》1985,32(1):163-166
Sodium dodecyl sulfate (SDS) and 2-mercaptoethanol (2-ME) activated proteolytic enzymes present in extracts of Entamoeba histolytica and E. invadens; SDS (0.5%) and 2-ME (1.4 and 715 mM) doubled the enzymatic activity when assayed on a stained insoluble substrate. Urea (4 M) did not reduce this activity, suggesting that amebic proteases are stable in the above denaturant conditions. Specific reagents for sulfhydryl (-SH) groups completely inhibited proteolytic activity regardless of pH. Inhibition with alkylating agents, such as N-ethylmaleimide and iodoacetamide, was reversed with 715 mM 2-ME as was also observed with papain. We conclude from these results that the main proteolytic enzymes contained in extracts of E. histolytica and E. invadens are dependent on free thiol groups. 相似文献
193.
Víctor E Balderas-Hernández Andrea Sabido-Ramos Patricia Silva Natividad Cabrera-Valladares Georgina Hernández-Chávez José L Báez-Viveros Alfredo Martínez Francisco Bolívar Guillermo Gosset 《Microbial cell factories》2009,8(1):19-12
Background
Anthranilate is an aromatic amine used industrially as an intermediate for the synthesis of dyes, perfumes, pharmaceuticals and other classes of products. Chemical synthesis of anthranilate is an unsustainable process since it implies the use of nonrenewable benzene and the generation of toxic by-products. In Escherichia coli anthranilate is synthesized from chorismate by anthranilate synthase (TrpED) and then converted to phosphoribosyl anthranilate by anthranilate phosphoribosyl transferase to continue the tryptophan biosynthetic pathway. With the purpose of generating a microbial strain for anthranilate production from glucose, E. coli W3110 trpD9923, a mutant in the trpD gene that displays low anthranilate producing capacity, was characterized and modified using metabolic engineering strategies. 相似文献194.
195.
Natividad Cuadrado-Corrales Adolfo Jiménez-Huete Carmen Albo Rafael Hortigüela Luz Vega Laura Cerrato Maríajosé Sierra-Moros Alberto Rábano Jesús de Pedro-Cuesta Miguel Calero 《BMC neurology》2006,6(1):25-8
Background
The 14-3-3 test appears to be a valuable aid for the clinical diagnosis of sporadic Creutzfeldt-Jakob disease (sCJD) in selected populations. However, its usefulness in routine practice has been challenged. In this study, the influence of the clinical context on the performance of the 14-3-3 test for the diagnosis of sCJD is investigated through the analysis of a large prospective clinical series. 相似文献196.
Light and temperature interaction in the photocontrol of germination of seeds in Ludwigia octovalvis
Summary The germination response of seeds of Ludwigia octovalvis (Jacq.) (=Jussiaea suffruticosa L.; Raven, 1963), to continuous light and to various types of intermittent irradiations is determined at 25, 30, 35 and 40° at different light intensities. At 25 and 40° intermittent irradiations are an effective substitute for continuous ones, while at 30 and 35° no promotion of germination is observed in the intermittent irradiations tested, except if the dark interval between light pulses is reduced to 1 min. Previous results obtained in the photocontrol of germination in this species are confirmed and extended to a variety of light cycles and intensities, indicating that the response to temperature is bimodal unless light is supplied continuously with high intensity, and that germination depends on light intensity more markedly in the temperature region of minimum germination (30–35°). As germination in this species is controlled by the red far-red system, hypothesis to account for the temperature dependence are based on the interaction between temperature and the reactions in which phytochrome is involved.Abbreviations L
light
- D
darkness 相似文献
197.
Fernando López-Soto Nidia León-Sicairos Kamran Nazmi Jan G. Bolscher Mireya de la Garza 《Biometals》2010,23(3):563-568
Entamoeba histolytica is a parasitic protozoan that produces amoebiasis, an intestinal disease characterized by ulcerative colitis and dysentery.
In some cases, trophozoites can travel to the liver leading to hepatic abscesses and death. Recently, lactoferrin and lactoferricin
B have been shown to be amoebicidal in axenic cultures. The aim of this work was to determine whether the lactoferrin-peptides
lactoferricin amino acids 17–30, lactoferrampin amino acids 265–284, and lactoferrin chimera which is a fusion product of
the two peptides, are capable of producing a microbicidal effect to trophozoites of E. histolytica. We evaluated the killing effect of these peptides in growth kinetics carried out in axenic culture medium to which different
concentrations of peptides were added. At 50 μM of peptide concentration, lactoferricin and lactoferrampin had a moderate
amoebicidal effect, since a 45–50% of trophozoites remained viable at 24 h culture. However, at 50 μM of the lactoferrin chimera
75% amoeba were killed whereas at 100 μM all cells died. These data indicate that of lactoferrin-peptides mainly the chimera
have amoebicidal activity in a time- and concentration-dependent manner. The lactoferrin-peptides might be useful as therapeutic
agents against amoebiasis and thereby diminish the use of metronidazole, which is extremely toxic for the host. 相似文献
198.
Nayely Garibay-Nieto Brianda Areli Hernández-Morán Eréndira Villanueva-Ortega María José Garcés-Hernández Karen Pedraza-Escudero América Arroyo-Valerio César Pedraza-Helvert Arturo Herrera-Rosas Estibalitz Laresgoiti-Servitje Mireya León-Hernández Neyla Baltazar-López Joselin Hernández-Ruíz Fabiola Serratos-Canales Gloria Queipo-García Sarah Elizabeth Messiah Srinivas Mummidi Juan Carlos López-Alvarenga 《Endocrine practice》2022,28(3):315-320
ObjectiveTo describe a third-degree polynomial function (hysteresis) of the effect size of age, obesity, and insulin sensitivity over the carotid intima-media thickness (c-IMT), in the pediatric and adult groups.MethodsA quasi-experimental study with fixed factor analysis of age (children aged 8-12 years, n = 73; adults aged 21-45 years, n = 82) and obesity (yes, n = 76; no, n = 79) was conducted to analyze the effect on the c-IMT and Matsuda insulin sensitivity index values. This quasi-experimental design was analyzed with robust regression modeling.ResultsThe additive effect of obesity, independent of age, was evident in the case of the c-IMT values. There was no interaction effect, but a significant difference between participants with normal weight and those with obesity was found (P < .0001). The difference between adults and children was also significant, but the effect size was smaller. A model was created based on age, Tanner stage, and obesity using the c-IMT and Matsuda insulin sensitivity index values. A linear function fit as R2, and the cubic function estimated parameters like a polynomial model.ConclusionThis practical study design showed that children with obesity displayed the same levels of carotid intima-media abnormalities as adults with obesity. The polynomial shape of the model suggests potentially poor outcomes that resemble the hysteresis process and may predict chronic cardiometabolic events during early adulthood. 相似文献