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1.
Langmuir ; 35(15): 5353-5363, 2019 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-30932499

RESUMO

Hydrophobic surfaces are of high interest to industry. While surface functionalization has attracted significant interest, from both industry and research, the durability of engineered surfaces remains a challenge, as wear and scratches deteriorate their functional response. In this work, a cost-effective combination of surface engineering processes on stainless steel was investigated. Low-temperature plasma surface alloying was applied to increase surface hardness from 172 to 305 HV. Then, near-infrared nanosecond laser patterning was deployed to fabricate channel-like patterns that enabled superhydrophobicity. Abrasion tests were carried out to examine the durability of such engineered surfaces during daily use. In particular, the evolution of surface topographies, chemical composition, and water contact angle with increasing abrasion cycles were studied. Hydrophobicity deteriorated progressively on both hardened and raw stainless steel samples, suggesting that the major contributing factor to hydrophobicity was the surface chemical composition. At the same time, samples with increased surface hardness exhibited a slower deterioration of their topographies when compared with nontreated surfaces. A conclusion is made about the durability of laser-textured hardened stainless steel surfaces produced by applying the proposed combined surface engineering approach.

2.
Int Psychogeriatr ; 28(10): 1725-35, 2016 10.
Artigo em Inglês | MEDLINE | ID: mdl-27189383

RESUMO

BACKGROUND: The influence of organizational culture on how psychotropic medicines are used in nursing homes has not been extensively studied. Schein's theory provides a framework for examining organizational culture which begins with the exploration of visible components of an organization such as behaviors, structures, and processes. This study aimed to identify key visible components related to the use of psychotropic medicines in nursing homes. METHODS: A qualitative study was conducted in eight nursing homes in Sydney, Australia. Purposive sampling was used to conduct semi-structured interviews with 40 participants representing a broad range of health disciplines. Thematic analysis was used to derive concepts. RESULTS: Three visible components were related to psychotropic medicine use. These were drugs and therapeutics committee meetings, pharmacist led medication management reviews and formal and informal meetings with residents and their families. We found that only a few nursing homes utilized drugs and therapeutics committee meetings to address the overuse of psychotropic medicines. Pharmacist led medication management reviews provided a lever to minimize inappropriate psychotropic prescribing for a number of nursing homes; however, in others it was used as a box-ticking exercise. We also found that some nursing homes used meetings with residents and their families to review the use of psychotropic medicines. CONCLUSION: This study was the first to illustrate that visible components of organizational culture do influence the use of psychotropic medicines and explains in detail what of the culture needs to be addressed to reduce inappropriate psychotropic prescribing.


Assuntos
Instituição de Longa Permanência para Idosos , Prescrição Inadequada , Assistência de Longa Duração , Conduta do Tratamento Medicamentoso/organização & administração , Casas de Saúde , Cultura Organizacional , Idoso , Austrália , Instituição de Longa Permanência para Idosos/organização & administração , Instituição de Longa Permanência para Idosos/normas , Humanos , Prescrição Inadequada/prevenção & controle , Prescrição Inadequada/estatística & dados numéricos , Assistência de Longa Duração/métodos , Assistência de Longa Duração/normas , Casas de Saúde/organização & administração , Casas de Saúde/normas , Padrões de Prática Médica/estatística & dados numéricos , Psicotrópicos/uso terapêutico , Pesquisa Qualitativa , Gestão da Segurança/métodos
3.
Parasite Immunol ; 37(9): 446-52, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26094646

RESUMO

Haemonchus contortus is a parasitic nematode of Pelibuey sheep, a meat breed used in tropical regions. Due to anthelmintic problems, the identification of hosts resistant to H. contortus is another option of control. The aim of this study was to analyse the relative expression of IL-5 and IL-6 genes in Pelibuey sheep after H. contortus infection. Nineteen lambs infected with H. contortus and three more lambs without infection were studied. The haemonchosis was determined by the number of eggs per gram of faeces (epg) and by the estimation of the percentage of the packed cell volume (%pcv). Peripheral blood mononuclear cells (PBMCs) were obtained to extract RNA at 0, 1, 2, 7, 14, 21 and 28 days after infection to quantify the relative expression of IL-5, IL-6 and GAPDH by real-time PCR. Five lambs were classified as low responders (lr) to haemonchosis with averages of 1519 ± 315·3 epg and 31·49 ± 5·13%pcv, and 14 lambs were identified as high responders (hr) with averages of 530 ± 132 epg and 34·88 ± 3·75%pcv. The expression ratio of IL-5 was significantly different compared with control lambs at 2, 7 and 14 days post-infection (PI), and IL-6 was significantly different after 14 days. The highest level of relative expression for IL-5 and IL-6 genes was 9·9-fold and 12-fold after 2 and 14 days for hr hosts (P < 0·05) compared with control group, respectively. In conclusion, the Pelibuey breed in grazing areas exhibited different expression of IL-5 and IL-6 obtained from PBMCs against H. contortus, suggesting the importance of these cytokines in regulating the nematode infection.


Assuntos
Hemoncose/veterinária , Haemonchus/fisiologia , Interleucina-5/imunologia , Interleucina-6/imunologia , Doenças dos Ovinos/imunologia , Animais , Fezes/parasitologia , Hemoncose/imunologia , Hemoncose/parasitologia , Interleucina-5/genética , Interleucina-6/genética , Leucócitos Mononucleares/imunologia , México , Contagem de Ovos de Parasitas , Reação em Cadeia da Polimerase em Tempo Real , Ovinos , Doenças dos Ovinos/parasitologia
4.
J La State Med Soc ; 167(3): 154, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-27159478

RESUMO

Hashimoto's Encephalopathy (HE) is a rare syndrome of steroid-responsive encephalopathy associated with elevated serum antithyroid antibody concentrations. The presentation of HE is highly variable making it difficult to recognize.

5.
Nature ; 455(7216): 1082-4, 2008 Oct 23.
Artigo em Inglês | MEDLINE | ID: mdl-18948949

RESUMO

Galaxies are complex systems the evolution of which apparently results from the interplay of dynamics, star formation, chemical enrichment and feedback from supernova explosions and supermassive black holes. The hierarchical theory of galaxy formation holds that galaxies are assembled from smaller pieces, through numerous mergers of cold dark matter. The properties of an individual galaxy should be controlled by six independent parameters including mass, angular momentum, baryon fraction, age and size, as well as by the accidents of its recent haphazard merger history. Here we report that a sample of galaxies that were first detected through their neutral hydrogen radio-frequency emission, and are thus free from optical selection effects, shows five independent correlations among six independent observables, despite having a wide range of properties. This implies that the structure of these galaxies must be controlled by a single parameter, although we cannot identify this parameter from our data set. Such a degree of organization appears to be at odds with hierarchical galaxy formation, a central tenet of the cold dark matter model in cosmology.

6.
Antimicrob Agents Chemother ; 57(3): 1474-9, 2013 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-23295937

RESUMO

It is more convenient and practical to collect rectal swabs than stool specimens to study carriage of colon pathogens. In this study, we examined the ability to use rectal swabs rather than stool specimens to quantify Klebsiella pneumoniae carbapenemase (KPC)-producing carbapenem-resistant Enterobacteriaceae (CRE). We used a quantitative real-time PCR (qPCR) assay to determine the concentration of the bla(KPC) gene relative to the concentration of 16S rRNA genes and a quantitative culture-based method to quantify CRE relative to total aerobic bacteria. Our results demonstrated that rectal swabs are suitable for quantifying the concentration of KPC-producing CRE and that qPCR showed higher correlation between rectal swabs and stool specimens than the culture-based method.


Assuntos
Proteínas de Bactérias/genética , Colo/microbiologia , Infecções por Klebsiella/microbiologia , Klebsiella pneumoniae/isolamento & purificação , RNA Ribossômico 16S/genética , beta-Lactamases/genética , Antibacterianos/farmacologia , Proteínas de Bactérias/isolamento & purificação , Técnicas de Tipagem Bacteriana , Carbapenêmicos/farmacologia , Fezes/microbiologia , Humanos , Infecções por Klebsiella/diagnóstico , Infecções por Klebsiella/tratamento farmacológico , Klebsiella pneumoniae/efeitos dos fármacos , Klebsiella pneumoniae/genética , Reação em Cadeia da Polimerase em Tempo Real , Manejo de Espécimes , Resistência beta-Lactâmica/efeitos dos fármacos , beta-Lactamases/isolamento & purificação
7.
AIDS Behav ; 16(7): 1775-86, 2012 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-22644068

RESUMO

Vaginal rings (VRs) are new methods for continuous delivery of microbicides. This is the first study to quantitatively and qualitatively explore the acceptability of rings in Africa: 157 HIV-negative, sexually active women aged 18-35 used a placebo silicone elastomer ring for 12 weeks. They completed product acceptability questionnaires every 4 weeks. We conducted 6 exit focus group discussions with a subset of 48 women and 19 in-depth interviews with male partners. Retention in the study was high (97 %). Initial insertion at the clinic was successful on first attempt for 81 % of participants. Most women were comfortable using the ring, and very few (≤2 %) could feel it during daily activities or had ring-related physical or emotional problems. In the qualitative interviews many participants reported that they initially had concerns about using the ring. However, only a minority of women actually reported concerns with the ring during the study. The most frequent concern was that the ring would get lost inside the body (20 %), and this was significantly correlated with study site, frequently thinking about the ring and reporting that the ring was not very easy to remove. Qualitative data suggest that informants grew to like the ring because it felt securely placed, was unnoticeable during daily activities, and felt "normal" during sex. The ring appeared to be highly acceptable for women and men. Initial concerns with this novel method suggest a need for enhanced product counseling when VRs are introduced.


Assuntos
Anti-Infecciosos/administração & dosagem , Dispositivos Anticoncepcionais Femininos/estatística & dados numéricos , Infecções por HIV/prevenção & controle , Aceitação pelo Paciente de Cuidados de Saúde/estatística & dados numéricos , Administração Intravaginal , População Negra/psicologia , Estudos Cross-Over , Feminino , Grupos Focais , Humanos , Entrevistas como Assunto , Análise Multivariada , Satisfação do Paciente , Pesquisa Qualitativa , Comportamento Sexual , Parceiros Sexuais/psicologia , Fatores Socioeconômicos , África do Sul , Inquéritos e Questionários , Tanzânia
8.
AIDS Behav ; 16(7): 1787-98, 2012 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-22790902

RESUMO

In sub-Saharan Africa, HIV incidence and prevalence remain disproportionately high among women. Vaginal rings (VRs) have been formulated for the delivery of antiretroviral-based microbicides, and their favorable safety and tolerability profiles reported in clinical studies. Although the concept of drug release through a VR has existed since 1970, and VRs have been marketed since 1992 for contraceptive or hormone replacement purposes, VR use as a microbicide delivery system is a novel application. This is the first study to evaluate VR adherence among African women in the context of its potential use as an HIV prevention method, to examine predictors of adherence, and to describe clinical or contextual reasons for VR removals or nonadherence. This was a randomized trial of the safety and acceptability of a placebo VR worn for 12 weeks in 170 HIV-negative, African women aged 18-35 in four clinic sites in South Africa and Tanzania. The findings suggest that adherence to VR use in the context of HIV prevention trials in these communities should be high, thereby enabling more accurate assessment of an active microbicide safety and efficacy.


Assuntos
Anti-Infecciosos Locais/administração & dosagem , Dispositivos Anticoncepcionais Femininos/estatística & dados numéricos , Infecções por HIV/prevenção & controle , Adesão à Medicação/estatística & dados numéricos , Administração Intravaginal , Adolescente , Adulto , Anti-Infecciosos Locais/efeitos adversos , Estudos Cross-Over , Feminino , Humanos , Adesão à Medicação/etnologia , Adesão à Medicação/psicologia , Análise Multivariada , Pesquisa Qualitativa , Fatores Socioeconômicos , África do Sul , Tanzânia , Adulto Jovem
10.
Pulmonology ; 28(6): 454-460, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-32739327

RESUMO

BACKGROUND: It is critical to developing an accurate method for differentiating between malignant and benign solitary pulmonary nodules. This study aimed was to establish a predicting model of lung nodules malignancy in a real-world setting. METHODS: The authors retrospectively analysed the clinical and computed tomography (CT) data of 121 patients with lung nodules, submitted to percutaneous CT-guided transthoracic biopsy, between 2014 and 2015. Multiple logistic regression was used to screen independent predictors for malignancy and to establish a clinical prediction model to evaluate the probability of malignancy. RESULTS: From a total of 121 patients, 75 (62%) were men and with a mean age of 64.7 years old. Multivariate logistic regression analysis identified six independent predictors of malignancy: age, gender, smoking status, current extra-pulmonary cancer, air bronchogram and nodule size (p<0.05). The area under the curve (AUC) was 0.8573. CONCLUSIONS: The prediction model established in this study can be used to assess the probability of malignancy in the Portuguese population, thereby providing help for the diagnosis of lung nodules and the selection of follow-up interventions.


Assuntos
Neoplasias Pulmonares , Modelos Estatísticos , Masculino , Humanos , Pessoa de Meia-Idade , Feminino , Estudos Retrospectivos , Prognóstico , Neoplasias Pulmonares/diagnóstico , Neoplasias Pulmonares/patologia , Pulmão/patologia
11.
Parasitology ; 138(11): 1341-53, 2011 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-21816124

RESUMO

The description of Plasmodium ookinete surface proteins and their participation in the complex process of mosquito midgut invasion is still incomplete. In this study, using phage display, a consensus peptide sequence (PWWP) was identified in phages that bound to the Plasmodium berghei ookinete surface and, in selected phages, bound to actin and enolase in overlay assays with ookinete protein extracts. Actin was localized on the surface of fresh live ookinetes by immunofluorescence and electron microscopy using specific antibodies. The overall results indicated that enolase and actin can be located on the surface of ookinetes, and suggest that they could participate in Plasmodium invasion of the mosquito midgut.


Assuntos
Actinas/metabolismo , Aedes/metabolismo , Anopheles/metabolismo , Sistema Digestório/metabolismo , Estágios do Ciclo de Vida/genética , Peptídeos/metabolismo , Fosfopiruvato Hidratase/metabolismo , Plasmodium berghei , Aedes/genética , Aedes/parasitologia , Sequência de Aminoácidos , Animais , Anopheles/genética , Anopheles/parasitologia , Extratos Celulares , Células Cultivadas , Sequência Conservada , Sistema Digestório/parasitologia , Imunofluorescência , Malária/metabolismo , Malária/parasitologia , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Microscopia Eletrônica , Dados de Sequência Molecular , Biblioteca de Peptídeos , Peptídeos/química , Peptídeos/genética , Plasmodium berghei/genética , Plasmodium berghei/metabolismo , Proteínas de Protozoários/metabolismo , Doenças dos Roedores/metabolismo , Doenças dos Roedores/parasitologia
12.
Rev Esp Anestesiol Reanim ; 58(3): 174-7, 2011 Mar.
Artigo em Espanhol | MEDLINE | ID: mdl-21534293

RESUMO

Extracorporeal membrane oxygenation (ECMO) is used in the treatment of severe respiratory failure that is potentially reversible. This mode of therapy reduces ventilator-associated lung injury. Although ECMO is costly and not free of complications, its early application by experienced multidisciplinary teams can improve survival. We report a case of acute respiratory distress syndrome in a patient who had received a liver transplant. Respiratory failure was unresponsive to conventional treatment and the patient required ECMO until recovery.


Assuntos
Oxigenação por Membrana Extracorpórea , Transplante de Fígado , Complicações Pós-Operatórias/terapia , Síndrome do Desconforto Respiratório/terapia , Humanos , Masculino , Pessoa de Meia-Idade
13.
Antimicrob Agents Chemother ; 53(2): 487-95, 2009 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-19029331

RESUMO

Heterosexual transmission of human immunodeficiency virus (HIV) remains the major route of infection worldwide; thus, there is an urgent need for additional prevention strategies, particularly strategies that could be controlled by women, such as topical microbicides. Potential microbicide candidates must be both safe and effective. Using cellular and tissue explant models, we have evaluated the activity of the nonnucleoside reverse transcriptase inhibitor (NNRTI) dapivirine as a vaginal microbicide. In tissue compatibility studies, dapivirine was well tolerated by epithelial cells, T cells, macrophages, and cervical tissue explants. Dapivirine demonstrated potent dose-dependent inhibitory effects against a broad panel of HIV type 1 isolates from different clades. Furthermore, dapivirine demonstrated potent activity against a wide range of NNRTI-resistant isolates. In human cervical explant cultures, dapivirine was able not only to inhibit direct infection of mucosal tissue but also to prevent the dissemination of the virus by migratory cells. Activity was retained in the presence of semen or a cervical mucus simulant. Furthermore, dapivirine demonstrated prolonged inhibitory effects: it was able to prevent both localized and disseminated infection for as long as 6 days posttreatment. The prolonged protection observed following pretreatment of genital tissue and the lack of observable toxicity suggest that dapivirine has considerable promise as a potential microbicide candidate.


Assuntos
Fármacos Anti-HIV/uso terapêutico , Infecções por HIV/tratamento farmacológico , HIV-1/efeitos dos fármacos , Pirimidinas/uso terapêutico , Inibidores da Transcriptase Reversa/uso terapêutico , Fármacos Anti-HIV/toxicidade , Células Cultivadas , Colo do Útero/virologia , Relação Dose-Resposta a Droga , Feminino , Humanos , Luciferases/metabolismo , Macrófagos/efeitos dos fármacos , Macrófagos/virologia , Técnicas de Cultura de Órgãos , Pirimidinas/toxicidade , Inibidores da Transcriptase Reversa/toxicidade , Linfócitos T/efeitos dos fármacos , Linfócitos T/virologia
14.
J Cell Biol ; 132(5): 795-811, 1996 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-8603913

RESUMO

A Tyr to Cys mutation at amino acid position 723 in the cytoplasmic domain of the simian immunodeficiency virus (SIV) transmembrane (TM) molecule has been shown to increase expression of envelope glycoproteins on the surface of infected cells. Here we show that Tyr-723 contributes to a sorting signal that directs the rapid endocytosis of viral glycoproteins from the plasma membrane via coated pits. On cells infected by SIVs with a Tyr at position 723, envelope glycoproteins were transiently expressed on the cell surface and then rapidly endocytosed. Similar findings were noted for envelope molecules expressed in the absence of other viral proteins. Immunoelectron microscopy demonstrated that these molecules were localized in patches on the cell surface and were frequently associated with coated pits. In contrast, envelope glycoproteins containing a Y723C mutation were diffusely distributed over the entire plasma membrane. To determine if an internalization signal was present in the SIV TM, chimeric molecules were constructed that contained the CD4 external and membrane spanning domains and a SIV TM cytoplasmic tail with a Tyr or other amino acids at SIV position 723. In Hela cells stably expressing these molecules, chimeras with a Tyr-723 were rapidly endocytosed, while chimeras containing other amino acids at position 723, including a Phe, were internalized at rates only slightly faster than a CD4 molecule that lacked a cytoplasmic domain. In addition, the biological effects of the internalization signal were evaluated in infectious viruses. A mutation that disrupted the signal and as a result, increased the level of viral envelope glycoprotein on infected cells, was associated with accelerated infection kinetics and increased cell fusion during viral replication. These results demonstrate that a Tyr-dependent motif in the SIV TM cytoplasmic domain can function as an internalization signal that can modulate expression of the viral envelope molecules on the cell surface and affect the biological properties of infectious viruses. The conservation of an analogous Tyr in all human and simian immunodeficiency viruses suggests that this signal may be present in other primate lentiviruses and could be important in the pathogenesis of these viruses in vivo.


Assuntos
Compartimento Celular , Membrana Celular/metabolismo , Endocitose , Produtos do Gene env/metabolismo , Proteínas Oncogênicas de Retroviridae/metabolismo , Vírus da Imunodeficiência Símia/metabolismo , Proteínas Virais de Fusão/metabolismo , Sequência de Aminoácidos , Animais , Sequência de Bases , Transporte Biológico , Antígenos CD4/genética , Antígenos CD4/metabolismo , Membrana Celular/ultraestrutura , Células Cultivadas , Clatrina , Invaginações Revestidas da Membrana Celular , Regulação Viral da Expressão Gênica , Produtos do Gene env/genética , Produtos do Gene env/ultraestrutura , Humanos , Camundongos , Dados de Sequência Molecular , Proteínas Recombinantes de Fusão/metabolismo , Proteínas Oncogênicas de Retroviridae/genética , Proteínas Oncogênicas de Retroviridae/ultraestrutura , Vírus da Imunodeficiência Símia/genética , Vírus da Imunodeficiência Símia/crescimento & desenvolvimento , Relação Estrutura-Atividade , Proteínas Virais de Fusão/genética , Proteínas Virais de Fusão/ultraestrutura
15.
Science ; 254(5039): 1791-4, 1991 Dec 20.
Artigo em Inglês | MEDLINE | ID: mdl-1840704

RESUMO

Transient activation of the interleukin-2 (IL-2) gene after antigen recognition by T lymphocytes is crucial for subsequent T cell proliferation and differentiation. Several IL-2 gene regulatory elements and binding factors necessary for activation of the IL-2 gene have been defined. However, little is known about negative regulation of IL-2 expression, which is likely to be important in the rapid shut-off of IL-2 transcription. A nucleotide sequence element (NRE-A) that negatively regulates IL-2 expression has been identified within the IL-2 gene. T cell nuclear extracts contained an NRE-A binding activity. A complementary DNA was isolated that encodes a zinc finger-containing protein that suppressed IL-2 gene expression. The observation of negative regulation of the immunoglobulin heavy chain gene enhancer by an element similar to NRE-A suggests that related proteins may regulate multiple immune response genes.


Assuntos
Elementos Facilitadores Genéticos , Regulação da Expressão Gênica , Genes de Imunoglobulinas , Cadeias Pesadas de Imunoglobulinas/genética , Interleucina-2/genética , Linfócitos T/imunologia , Transcrição Gênica , Dedos de Zinco/genética , Sequência de Aminoácidos , Animais , Sequência de Bases , Linhagem Celular , Sondas de DNA , Humanos , Camundongos , Dados de Sequência Molecular , Oligodesoxirribonucleotídeos , Sequências Reguladoras de Ácido Nucleico , Mapeamento por Restrição , Dedos de Zinco/fisiologia
16.
Vis Neurosci ; 26(3): 309-18, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19523265

RESUMO

The pond turtle (Trachemys scripta elegans) exhibits a notably sluggish pupillary light reflex (PLR), with pupil constriction developing over several minutes following light onset. In the present study, we examined the dynamics of the efferent branch of the reflex in vitro using preparations consisting of either the isolated head or the enucleated eye. Stimulation of the oculomotor nerve (nIII) using 100-Hz current trains resulted in a maximal pupil constriction of 17.4% compared to 27.1% observed in the intact animal in response to light. When current amplitude was systematically increased from 1 to 400 microA, mean response latency decreased from 64 to 45 ms, but this change was not statistically significant. Hill equations fitted to these responses indicated a current threshold of 3.8 microA. Stimulation using single pulses evoked a smaller constriction (3.8%) with response latencies and threshold similar to that obtained using train stimulation. The response evoked by postganglionic stimulation of the ciliary nerve using 100-Hz trains was largely indistinguishable from that of train stimulation of nIII. However, application of single-pulse stimulation postganglionically resulted in smaller pupil constriction at all current levels relative to that of nIII stimulation, suggesting that there is amplification of efferent drive at the ganglion. Time constants for constrictions ranged from 88 to 154 ms with relaxations occurring more slowly at 174-361 ms. These values for timing from in vitro are much faster than the time constant 1.66 min obtained for the light response in the intact animal. The rapid dynamics of pupil constriction observed here suggest that the slow PLR of the turtle observed in vivo is not due to limitations of the efferent pathway. Rather, the sluggish response probably results from photoreceptive mechanisms or central processing.


Assuntos
Nervo Oculomotor/fisiologia , Reflexo Pupilar/fisiologia , Tartarugas/fisiologia , Animais , Corpo Ciliar/inervação , Vias Eferentes/fisiologia , Estimulação Elétrica/métodos , Feminino , Técnicas In Vitro , Masculino , Modelos Biológicos , Fenômenos Fisiológicos do Sistema Nervoso , Tempo de Reação
19.
Domest Anim Endocrinol ; 68: 106-110, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-31026742

RESUMO

The objectives of this investigation were to determine the effect of the time of copulation during the estrus period on estrus duration and luteinizing hormone (LH) response in goats. A controlled randomized study with two replicates (first = n = 12; second = n = 24), in which Boer does were divided at each replicate into three groups, was performed. Copulations at the beginning of estrus (two copulas within the first 4 h after estrus; COP-1; n = 12), copulations around the middle of estrus (two copulas around 16 h after estrus; COP-2; n = 12), and noncopulations (only mounts) throughout the estrus period (control group; CON; n = 12) were performed. Estrus duration for CON group was 41.3 ± 8.2 h; for COP-1, it was 34.0 ± 5.3 h, and for COP-2, it was 39.7 ± 6.9 h (P = 0.04). Differences were detected between COP-1 and CON groups (P = 0.01) and between COP-1 and COP-2 groups (P = 0.05) but not between CON and COP-2 groups (P = 0.56). The LH peak time for the CON group was 20.0 ± 8.0 h; for the COP-1 group, it was 13.0 ± 3.6 h, and for the COP-2 group, it was 20.5 ± 5.8 h (P = 0.04). The COP-1 group was different than the COP-2 (P = 0.02) and CON groups (P = 0.03), and no differences were detected between these last two groups (P = 0.87). It was concluded that copulation reduced estrus duration and hastened the LH peak time only when performed during the beginning of estrus.


Assuntos
Copulação/fisiologia , Estro/fisiologia , Cabras/fisiologia , Hormônio Luteinizante/fisiologia , Animais , Feminino , Hormônio Luteinizante/sangue , Masculino , Gravidez , Fatores de Tempo
20.
J Dairy Sci ; 91(3): 1270-8, 2008 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-18292285

RESUMO

Jersey x Holstein crossbreds (JxH; n = 76) were compared with pure Holsteins (n = 73) for 305-d milk, fat, and protein production; conception rate; days open; proportion of cows pregnant within fixed intervals postpartum; and body and udder measurements during first lactation. Cows were housed at 2 research locations of the University of Minnesota and calved from September 2003 to May 2005. The JxH were mated to Montbeliarde sires, and Holstein cows were mated to Holstein sires. Best Prediction was used to determine actual production (milk, fat, and protein) for 305-d lactations with adjustment for age at calving, and records less than 305 d were projected to 305 d. The JxH (274 kg) and pure Holsteins (277 kg) were not significantly different for fat production, but JxH had significantly less milk (7,147 vs. 7,705 kg) and protein (223 vs. 238 kg) production than pure Holsteins. The JxH had significantly fewer days open than pure Holsteins (127 vs. 150 d). Also, a significantly greater proportion of JxH were pregnant at 150 and 180 d postpartum than pure Holsteins (75 vs. 59% and 77 vs. 61%, respectively). The JxH had significantly less body weight (60 kg) at calving, but significantly greater body condition (2.80 vs. 2.71). Furthermore, JxH had significantly less udder clearance from the ground to the bottom of the udder than pure Holsteins (47.7 vs. 54.6 cm), and greater distance between front teats (15.8 vs. 14.0 cm) than pure Holsteins during first lactation.


Assuntos
Bovinos/genética , Cruzamentos Genéticos , Fertilidade/genética , Lactação/genética , Glândulas Mamárias Animais/anatomia & histologia , Animais , Composição Corporal , Bovinos/anatomia & histologia , Bovinos/fisiologia , Gorduras/análise , Feminino , Masculino , Leite/química , Leite/citologia , Proteínas do Leite/análise , Gravidez
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