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21.
The electrical activity of the oviduct and uterus was automatically registered on a potentiometric pen recorder in ewes fitted with an extracellular multielectrode assembly. The duration and amplitude of local non-propagating activity of the uterus increased and became progressively grouped into phases as natural oestrus progressed. Phases of contractions lasting 5-6 min were initially propagated at a rate of 2/hr. Their frequency increased within 24 hr of the decline in plasma progesterone levels. Grouped activity was then resumed for the next 24 hr. Similar changes were seen in the activity of the oviduct although this region was active earlier in oestrus. The uterotubal activity developed in the same way 24 hr after withdrawal of a progestagen-impregnated sponge but lasted for 3 days. When another oestrus was induced by injection of a prostaglandin analogue, the activity patterns were qualitatively similar although they did not start until 36 hr after injection and lasted for only 2 days. 相似文献
22.
Lilia G Noriega Zesergio Melo Renuga D Rajaram Adriana Mercado Armando R Tovar Laura A VelazquezVillegas María CastaedaBueno Yazmín ReyesLpez Dongryeol Ryu Lorena RojasVega German MagaaAvila Adriana M LpezBarradas Mariana SnchezHernndez Anne Debonneville Alain Doucet Lydie Cheval Nimbe Torres Johan Auwerx Olivier Staub Gerardo Gamba 《EMBO reports》2021,22(5)
23.
Increasing global demands for food underline the need for higher crop yields. The relatively low costs of the most commonly used insecticides in combination with increasing soybean market prices led growers and technical advisors to debate the adequacy of recommended economic thresholds (ETs). The adoption of ETs and pest sampling has diminished in Brazil, leading to excessive pesticide use on soybean. The reduced efficacy of natural biological control, faster pest resurgence, and environment contamination are among the side-effects of pesticide abuse. To address these problems and maximize agricultural production, pest control programs must be guided by a proper integrated pest management (IPM) approach, including the ET concept. Therefore, the most appropriate time to initiate insecticide spraying in soybean is indicated by the available ETs which are supported by experiments over the last 40 years in different edapho-climatic conditions and regions with distinct soybean cultivars. Published scientific data indicate that preventive insecticide use is an expensive and harmful use of chemicals that increases the negative impact of pesticides in agroecosystems. However, the established ETs are for a limited number of species (key pests), and they only address the use of chemicals. There is a lack of information regarding secondary pests and other control strategies in addition to insecticides. It is clear then that much progress is still needed to improve ETs for pest management decisions. Nevertheless, using the current ETs provides a basis for reducing the use of chemicals in agriculture without reducing yields and overall production, thereby improving sustainability. 相似文献
24.
M. Bueno Martínez E. Román Galán J. A. Galbis Pérez 《Nucleosides, nucleotides & nucleic acids》2013,32(2):227-244
Abstract Fusion of 2-trimethylsilylpyridine and tetra-O-acetyl-aldehydo-D-xylose or 2,3:4,5-di-O-isopropylidene-aldehydo-L-arabinose led, after removing of the protecting groups, to 2-(pentitol-1-yl)pyridines of D-gulo and D-ido or L-manno configurations. Dehydration of the sugar-chain with D-gulo and D-ido configurations gave the corresponding 2′,5′-anhydro derivatives, whereas 2-(5-O-isopropyl-L-manno-pentitol-1-yl)-pyridine was the only compound formed by dehydration of the sugar-chain with L-manno configuration. Structural proofs are based on 1H and 13C NMR spectra. 相似文献
25.
Tatiana Aparecida Voltolin Manolo Penitente Bruna Bueno Mendon?a José Augusto Senhorini Fausto Foresti Fábio Porto-Foresti 《Genetics and molecular biology》2013,36(3):347-352
The family Prochilodontidae is considered a group with well conserved chromosomes characterized by their number, morphology and banding patterns. Thence, our study aimed at accomplishing a cytogenetic analysis with conventional methods (Giemsa staining, silver staining of the nucleolus organizer regions-AgNOR, and C-banding) and fluorescence in situ hybridization (FISH) with 18S and 5S ribosomal DNA probes in five species of the Prochilodus genus (Prochilodus argenteus, Prochilodus brevis, Prochilodus costatus, Prochilodus lineatus and Prochilodus nigricans) collected from different Brazilian hydrographic basins. The results revealed conservatism in chromosome number, morphology, AgNORs 18S and 5S rDNAs location and constitutive heterochromatin distribution patterns. The minor differences observed in this work, such as an Ag-NOR on a P. argenteus chromosome and a distinct C-banding pattern in P. lineatus, are not sufficient to question the conservatism described for this group. Future work using repetitive DNA sequences as probes for FISH will be interesting to further test the cytogenetic conservatism in Prochilodus. 相似文献
26.
M. Martínez-Sellés T. Datino L. M. Figueiras-Graillet H. Bueno F. Fernández-Aviles 《Netherlands heart journal》2013,21(11):499-503
Background
The influence of new-onset atrial fibrillation (AF) on the long-term prognosis of nonagenarians who survive acute myocardial infarction (AMI) has not been demonstrated.Objective
Our aim was to study the association between new-onset AF and long-term prognosis of nonagenarians who survive AMI.Methods
From a total of 96 patients aged ≥89 years admitted during a 5-year period, 64 (67 %) were discharged alive and are the focus of this study.Results
Mean age was 91.0 ± 2.0 years, and 39 patients (61 %) were women. During admission, 9 patients (14 %) presented new-onset AF, 51 (80 %) did not present AF, and 4 (6 %) had chronic AF. During follow-up (mean 2.3 ± 2.6 years; 6.6 ± 3.6 years in survivors), 58 patients (91 %) died, including the 9 patients with new-onset AF. Cumulative survival at 6, 12, 18, 24, and 30 months was 68.3 %, 57.2 %, 49.2 %, 47.6 %, and 31.8 %, respectively. The only two independent predictors of mortality in the multivariate analysis were age (hazard ratio [HR] 1.14; 95 % confidence interval [CI] 1.01–1.28; p = 0.04) and new-onset AF (HR 2.3; 95 % CI 1.1–4.8; p = 0.02).Conclusion
New-onset AF is a marker of poor prognosis in nonagenarians who survive AMI. 相似文献27.
Germana Bueno Dias Valdirene Moreira Gomes Umberto Zottich Pereira Suzanna F. Ferreira Ribeiro André O. Carvalho Rosana Rodrigues Olga L. Tavares Machado Kátia Valevski Sales Fernandes André Teixeira S. Ferreira Jonas Perales Maura Da Cunha 《The protein journal》2013,32(1):15-26
Capsicum species belong to the Solanaceae family and have great social, economic and agronomical significance. The present research presents data on the isolation and characterization of Capsicum chinense Jacq. peptides which were scrutinized in relation to their toxicity towards a diverse set of yeast species. The protein extract was separated with C18 reverse-phase chromatography in high performance liquid chromatography, resulting in three different peptide enriched fractions (PEFs) termed PEF1, PEF2 and PEF3. Tricine-SDS-PAGE of the PEF2 revealed peptides with molecular masses of approximately 5.0 and 8.5 kDa. These PEFs also exhibited strong antifungal activity against different yeasts. In the presence of the PEF2, Candida tropicalis exhibited morphological changes, including cellular agglomeration and formation of pseudohyphae. Determined N-terminal sequences of PEF2 and PEF3 were proven to be highly homologous to serine proteinase inhibitors, when analysed by comparative database sequence tools. For this reason were performed protease inhibitory activity assay. The PEFs displayed high inhibitory activity against trypsin and low inhibitory activity against chymotrypsin. PEF2 and PEF3 were considerably unsusceptible to a broad interval of pH and temperatures. Due to the myriad of application of Proteinase inhibitors (PIs) in fields ranging from plant protection against pathogens and pests to medicine such as in cancer and virus replication inhibition, the discovery of new PIs with new properties are of great interest. 相似文献
28.
Emilio García García María-Ángeles Vázquez López Rafael Galera Martínez Irene Alias Manuel Martín González Antonio Bonillo Perales José Eugenio Cabrera Sevilla Icíar García Escobar Sara Gómez Bueno Encarnación López Ruzafa Francisco-Javier Muñoz Vico Patricia Oliva Pérez María Ortiz Pérez Juan Poveda González Marisa Rodríguez Lucenilla Firma-Isabel Rodríguez Sánchez Ana Ruiz Sánchez Lucía Ruiz Tudela Sara Torrico 《Endocrinología y nutrición》2013,60(3):121-126
ObjectivesTo estimate the prevalence of obesity and overweight in children and adolescents in our city and to investigate the associated factors.Subjects and methodsA cross-sectional study of 1317 children and adolescents aged 2-16 years. Multistage probability sampling was used to select three groups of subjects: 411 aged 12 to 16 years, 504 aged 6 to 12 years, and 402 aged 2 to 6 years. Body mass index was calculated, and obesity and overweight were diagnosed using the threshold levels of the International Obesity Task Force for children and adolescents. Parents were asked about eating habits, health, social, and demographic aspects. Results are given as percentages (95% confidence interval). The relationship between obesity and overweight and the different variables was studied using multiple logistic regression. The adjusted odds ratio (OR) was calculated.ResultsAmong children and adolescentes aged 2-16 years, 9.5% (8.0%-11.0%) were obese and 22.4% (23.3%-24.6%) were overweight. Of subjects aged 12-16 years, 8.5% (5.9%-11.2%) were obese and 20.5% (16.7%-24.3%) were overweight. In the groups aged 6-12 years and 2-6 years, rates of obesity and overweight were 11.6% (8.9% -14.3%) and 31.0% (27.0-35.0) and 8.0% (5.4%-10.6%) and 13.6% (10.3%-16.9%) respectively. Obesity or overweight was associated to age (OR 1.21; P< 0.001), maternal obesity (OR 10.99; P= 0.008), a birthweight higher than 4 kg (OR 2.91; p 0.002), and formula feeding (OR 1.82; P= 0.005).ConclusionObesity and overweight in children and adolescents are highly prevalent problems in our city. 相似文献
29.
Leandro Bueno Bergantin Cláudio Fontes Souza Regiane Miranda Ferreira Soraya Soubhi Smaili Neide Hyppolito Jurkiewicz Afonso Caricati-Neto Aron Jurkiewicz 《Cell calcium》2013
It is well established that reduction of Ca2+ influx through L-type voltage-dependent Ca2+ channel (L-type VDCC), or increase of cytosolic cAMP concentration ([cAMP]c), inhibit contractile activity of smooth muscles in response to transmitters released from sympathetic nerves. Surprisingly, in this work we observed that simultaneous administration of L-type VDCC blocker (verapamil) and [cAMP]c enhancers (rolipram, IBMX and forskolin) potentiated purinergic contractions evoked by electrical field stimulation of rat vas deferens, instead of inhibiting them. These results, including its role in sympathetic transmission, can be considered as a “calcium paradox”. On the other hand, this potentiation was prevented by reduction of [cAMP]c by inhibition of adenylyl cyclase (SQ 22536) or depletion of Ca2+ storage of sarco-endoplasmic reticulum by blockade of Ca2+ reuptake (thapsigargin). In addition, cytosolic Ca2+ concentration ([Ca2+]c) evaluated by fluorescence microscopy in rat adrenal medullary slices was significantly reduced by verapamil or rolipram. In contrast, simultaneous incubation of adrenal slices with these compounds significantly increased [Ca2+]c. This effect was prevented by thapsigargin. Thus, a reduction of [Ca2+]c due to blockade of Ca2+ influx through L-type VDCC could stimulate adenylyl cyclase activity increasing [cAMP]c thereby stimulating Ca2+ release from endoplasmic reticulum, resulting in augmented transmitter release in sympathetic nerves and contraction. 相似文献
30.