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101.
Elevated concentrations of CSF corticotropin-releasing factor-like immunoreactivity in depressed patients 总被引:26,自引:0,他引:26
C B Nemeroff E Widerl?v G Bissette H Walléus I Karlsson K Eklund C D Kilts P T Loosen W Vale 《Science (New York, N.Y.)》1984,226(4680):1342-1344
The possibility that hypersecretion of corticotropin-releasing factor (CRF) contributes to the hyperactivity of the hypothalamo-pituitary-adrenal axis observed in patients with major depression was investigated by measuring the concentration of this peptide in cerebrospinal fluid of normal healthy volunteers and in drug-free patients with DSM-III diagnoses of major depression, schizophrenia, or dementia. When compared to the controls and the other diagnostic groups, the patients with major depression showed significantly increased cerebrospinal fluid concentrations of CRF-like immunoreactivity; in 11 of the 23 depressed patients this immunoreactivity was greater than the highest value in the normal controls. These findings are concordant with the hypothesis that CRF hypersecretion is, at least in part, responsible for the hyperactivity of the hypothalamo-pituitary-adrenal axis characteristic of major depression. 相似文献
102.
Cláudia B. Silva Sônia Maria Leite Ribeiro do Vale Francisco A. C. Pinto Carlos A. S. Müller Altair D. Moura 《Precision Agriculture》2007,8(6):255-265
The objective of this study was to carry out a comparative analysis of the costs and economic profitability and viability indicators involved in implementing precision and conventional farming practices using maize and soybean crops in the state of Mato Grosso do Sul, Brazil. After identifying the production costs, analyses of the profitability indicators and viability indicators were carried out. The calculated profitability indicators (gross revenue, gross margin, break-even point, operational profit, and profitability index) presented better economic results under the precision system. For the analysis of the viability indicators, the net present value method and the internal rate of return method were used to analyze the two production systems, showing smaller investment attractiveness for the conventional farming system than for the precision system, though with a small difference in values. The Monte Carlo method was applied to evaluate investment risk. The selection of the variables to be simulated was based on the sensitivity analysis results, such as production, sale price and input price. The results obtained through simulation led to the conclusion that the risks are low for the two production systems analyzed. 相似文献
103.
Patterns of growth hormone-releasing factor and somatostatin secretion into the hypophysial-portal circulation of the rat 总被引:20,自引:0,他引:20
The interrelation between the secretion of two hypophysiotropic peptides, growth hormone-releasing factor (GRF) and somatostatin (SRIF), in the generation of episodic growth hormone (GH) secretion was inferred from direct measurements of immunoreactive GRF and immunoreactive SRIF concentrations in the hypophysial-portal plasma of the rat. Secretion of immunoreactive GRF was found to be episodic, with maximal concentrations present during periods of expected GH secretory episodes. Secretion of immunoreactive GRF was accompanied by a moderate reduction in portal plasma levels of immunoreactive SRIF. Passive immunoneutralization of SRIF was associated with increased concentrations of immunoreactive GRF in hypophysial-portal plasma. On the basis of these observations, it appears that each GH secretory episode is initiated by pulsatile secretion of immunoreactive GRF into the portal circulation, which is preceded by or is concurrent with a moderate reduction of inhibitory tone provided by portal immunoreactive SRIF. These experiments provide direct insights into central and adenohypophysial mechanisms by which GRF and SRIF interact to generate episodic secretion of GH. 相似文献
104.
LS Barter JE Ilkiw EP Steffey BH Pypendop A Imai JA Bolich 《Veterinary anaesthesia and analgesia》2003,30(2):105-105
Minimum alveolar concentration (MAC) of an inhalant is an indicator of its anesthetic potency. Individuals vary in their sensitivity to anesthetic agents as demonstrated by different individual MAC values. We hypothesized that individual animal sensitivity would be maintained with different inhalant anesthetics. As part of separate studies, six female DSH cats, aged 24 ± 2.5 (mean ± SD) months and weighing 3.5 ± 0.3 kg, were studied similarly on three separate occasions over a 12‐month period to determine the MAC of isoflurane (ISO), sevoflurane (SEVO), and desflurane (DES), respectively. In each study, chamber induction was followed by orotracheal intubation, and anesthesia was maintained via a nonrebreathing circuit. ECG, pulse oximetry, Doppler systolic blood pressure, end‐tidal gases, and esophageal temperature were monitored. End‐tidal gases were hand‐sampled from a catheter whose tip lay level with the distal end of the ET tube. Gases were analyzed by Raman spectrometry and, for each agent, the analyzer was calibrated with at least three gas standards. MAC was determined in triplicate using standard tail‐clamp technique. Data were analyzed by two‐way anova followed by Tukey's test and significant differences were found. Average MACs (%) for ISO, SEVO, and DES were 1.90 ± 0.18, 3.41 ± 0.65, and 10.27 ± 1.06, respectively. Body temperatures, Doppler systolic blood pressure, and SpO2 were recorded at the time of MAC determinations for ISO, SEVO, and DES were 38.3 ± 0.3, 38.6 ± 0.1, 38.3 ± 0.35 °C; 71 ± 8, 75 ± 16, 88 ± 12 mm Hg; 99 ± 1, 99 ± 1, 99 ± 1%, respectively. Both the anesthetic agent and the individual cat had significant effects on MAC (p = 0.0001 and 0.0185, respectively). MAC varied between individuals and cats were consistent in their order of sensitivity to inhalant anesthetics across the three agents. Within this group of cats, the relationship of individual MAC to the group MAC for each of the three inhalant agents was maintained. This suggests that any individual may be consistently more or less sensitive to a variety of inhalant agents. 相似文献
105.
Lidocaine dose‐dependently decreases the minimum alveolar concentration (MAC) of isoflurane in cats. The purpose of this study was to determine the hemodynamic effects of six lidocaine plasma concentrations in isoflurane anesthetized cats. Six cats were studied. After instrumentation, end‐tidal isoflurane concentration was set at 1.25 times the individual minimum alveolar concentration (MAC), which was determined in a previous study. Lidocaine was administered intravenously to target pseudo‐steady state plasma concentrations of 0, 3, 5, 7, 9, and 11 μg ml–1, and isoflurane concentration was reduced to an equipotent concentration, determined in a previous study. Cardiovascular variables; blood gases; PCV; total protein and lactate concentrations; and lidocaine and monoethylglycinexylidide concentrations were measured at each lidocaine target concentration, before and during noxious stimulation. Derived variables were calculated. Data were analyzed using a repeated measures anova , followed by a Tukey test for pairwise comparisons where appropriate. One cat was excluded from analysis because the study was aborted at 7 μg ml–1 due to severe cardiorespiratory depression. Heart rate, cardiac index, stroke index, right ventricular stroke work index, total protein concentration, mixed‐venous PO2 and hemoglobin oxygen saturation, arterial and mixed‐venous bicarbonate concentrations, and oxygen delivery were significantly lower during lidocaine administration than when no lidocaine was administered. Mean arterial pressure, central venous pressure, pulmonary artery pressure, systemic and pulmonary vascular resistance indices, PCV, arterial and mixed‐venous hemoglobin concentrations, lactate concentration, arterial oxygen concentration, and oxygen extraction ratio were significantly higher during administration of lidocaine than when no lidocaine was administered. Most changes were significant at lidocaine target plasma concentrations of 7 μg ml–1 and above. Noxious stimulation did not significantly affect most variables. Despite significantly decreasing in inhalant requirements, when combined with isoflurane, lidocaine produces greater cardiovascular depression than an equipotent dose of isoflurane alone. The use of lidocaine to reduce isoflurane requirements is not recommended in cats. 相似文献
106.
ST Rolim Filho HFL Ribeiro GMF de Camargo DF Cardoso RR Aspilcueta‐Borquis H Tonhati KB Nunes WG Vale EM Barbosa KC de Sousa 《Reproduction in domestic animals》2013,48(5):705-709
The osteopontin gene may influence the fertility of water buffaloes because it is a protein present in sperm. The aim of this work was to identify polymorphisms in this gene and associate them with fertility parameters of animals kept under extensive grazing. A total of 306 male buffaloes older than 18 months, from two farms, one in the state of Amapá and the other in the state of Pará, Brazil were used in the study. Seven SNPs were identified in the regions studied. The polymorphisms were in gene positions 1478, 1513 and 1611 in the region 5′upstrem and positions 6690, 6737, 6925 and 6952 in the region amplified in intron 5. The SNPs were associated with the traits, namely scrotal circumference, scrotal volume, sperm motility, sperm concentration and sperm pathology. There were significant SNPs (p < 0.05) for all the traits. The SNP 6690 was significant for scrotal circumference, sperm concentration, sperm motility and sperm pathology and the SNP 6737 for scrotal volume. The genotype AA of SNP 6690 presented the highest averages for scrotal circumference, sperm concentration and motility and the lowest total number of sperm pathologies. For the scrotal volume trait, the animals with the largest volume were correlated with the presence of the genotype GG of SNP 6737. These results indicate a significance of the osteopontin gene as it seems to exert a substantial influence on the semen production traits of male buffaloes. 相似文献
107.
KM Neil JE Axon AP Begg PG Todhunter PL Adams AE Fine JP Caron AR Adkins 《Australian veterinary journal》2010,88(1-2):4-12
Objective To determine the clinical characteristics, short-term outcome and future athletic performance of foals with septic osteomyelitis.
Design Retrospective clinical study of 108 Thoroughbred foals with radiographic evidence of bone infection that were presented at the Scone Veterinary Hospital between August 1995 and December 2001. Medical records were reviewed and information concerning signalment, the clinical, laboratory and radiographic findings, treatment and outcome was obtained. Racing records were obtained and evaluated for surviving foals that had reached racing age.
Results Mean age of foals at initial evaluation was 39 days (range 1–180 days); 21 foals had multiple radiographic bone lesions (19.4%), and 76 had concurrent septic arthritis (70.4%). The most frequently affected bones were the femur, tibia and distal phalanx. In total, 87 foals were discharged from the hospital (80.6%), 79 survived long-term to reach racing age and 52 raced (65.8%). Overall, 48% (52/108) of the foals treated for osteomyelitis raced. Foals less than 30 days of age at the time of diagnosis, critically ill foals and those with multiple bones or joints affected were significantly less likely to be discharged from hospital. Multiple septic joints, but not multiple bone involvement, had an unfavourable prognosis for racing.
Conclusions The prognosis for survival of foals with septic osteomyelitis or osteitis is favourable. Multiple bone or joint involvement is an important short-term prognostic indicator; however, the involvement of multiple joints, but not multiple infected bones, is associated with an unfavourable prognosis for racing. 相似文献
Design Retrospective clinical study of 108 Thoroughbred foals with radiographic evidence of bone infection that were presented at the Scone Veterinary Hospital between August 1995 and December 2001. Medical records were reviewed and information concerning signalment, the clinical, laboratory and radiographic findings, treatment and outcome was obtained. Racing records were obtained and evaluated for surviving foals that had reached racing age.
Results Mean age of foals at initial evaluation was 39 days (range 1–180 days); 21 foals had multiple radiographic bone lesions (19.4%), and 76 had concurrent septic arthritis (70.4%). The most frequently affected bones were the femur, tibia and distal phalanx. In total, 87 foals were discharged from the hospital (80.6%), 79 survived long-term to reach racing age and 52 raced (65.8%). Overall, 48% (52/108) of the foals treated for osteomyelitis raced. Foals less than 30 days of age at the time of diagnosis, critically ill foals and those with multiple bones or joints affected were significantly less likely to be discharged from hospital. Multiple septic joints, but not multiple bone involvement, had an unfavourable prognosis for racing.
Conclusions The prognosis for survival of foals with septic osteomyelitis or osteitis is favourable. Multiple bone or joint involvement is an important short-term prognostic indicator; however, the involvement of multiple joints, but not multiple infected bones, is associated with an unfavourable prognosis for racing. 相似文献
108.
Yeast extract on growth,nutrient utilization and haemato‐immunological responses of Nile tilapia
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Ricardo da Silva Berto Gabriella do Vale Pereira José Luiz Pedreira Mouriño Maurício Laterça Martins Débora Machado Fracalossi 《Aquaculture Research》2016,47(8):2650-2660
Dietary supplementation (0, 10, 20, 40, 60, 80 g kg?1) of a nucleotide source (NuPro®) was evaluated on growth, nutrient utilization, haemato‐immunological responses and resistance to experimental infection of Nile tilapia. Fish (2.63 ± 0.63 g) were fed experimental diets to satiation three times a day for 75 days. Feed intake increased linearly with increasing levels of NuPro® promoting higher weight gain (P < 0.05). Survival, feed conversion and protein retention were not affected. Following the growth trial, fish were challenged with Aeromonas hydrophila by intraperitoneal injection. Survival and innate immune responses (phagocytosis and lysozyme activity) were not significantly affected. However, among the haematological variables, thrombocyte, leucocyte and monocyte counts increased linearly (P < 0.05). The indirect measurement of digestibility in juvenile Nile tilapia (122.32 ± 11 g) indicated a linear decrease in protein (1.41%), dry matter (5.72%) and energy (4.10%) digestibility coefficients as dietary supplementation increased (P < 0.05). NuPro® showed to be a beneficial additive to be supplemented in diets for juvenile Nile tilapia, providing 32.8% increase in feed intake and 28.8% in weight gain, as well as in thrombocyte, leucocyte and monocyte counts in blood, possibly indicating a more efficient defence response in the highest dietary supplementation levels tested. 相似文献
109.
Maria Emanuella O. Martins Juliana R. Sousa Rayanne L. Claudino Sarah Cristina O. Lino Diego Alves do Vale André Luis C. Silva 《Journal Of Aquatic Food Product Technology》2013,22(10):1120-1133
ABSTRACTGelatin from the scale of Nile tilapia was extracted and characterized chemically, thermally, and structurally. Scales of Nile tilapia were subjected to acid pretreatment and extraction with water at 60°C. The process yielded 12.1% (m/m) on a dry basis. The 6.67% gelatin solution had a gel strength of 233.5 ± 14g. The amino acid composition revealed that 20.02% was comprised of imino acids and glycine (34.49%) as the most abundant amino acids. The scale gelatin had α1, α2, and β subunits and was thermally stable up to 200ºC. The Fourier transform infrared spectrum showed absorption in the regions of amides A, I, II, and III. The characterization of tilapia scale gelatin showed that the obtained product was similar to commercial gelatin, thereby demonstrating its potential application. 相似文献
110.
Origin of and resulting floristic composition from seedbanks in agroforestry systems of Tomé‐Açu,Eastern Amazon
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F Lacerda I Miranda T T S Lima N A Mafra F M Leão I Do Vale C J C Bispo O R Kato 《Weed Research》2016,56(3):219-228
The objective of this study was to verify the origin of and resulting floristic composition from seedbanks in different agroforestry systems in Tomé‐Açu, Brazil. The seedbanks were sampled in three smallholder farmers (Demonstration Units = DU), each with three agroforestry treatments and secondary forest as control. Seedling emergence in a glasshouse was used to quantify and identify the seeds collected in 2008. The floristic composition of the above‐ground community was characterised with annual floristic surveys from 2008 to 2011. The total densities and diversity of the seedbanks were not different among the treatments within a given DU, but differences occurred among DU. The most abundant woody species had higher seed densities in the secondary forests than in DU. Conversely, among the herbaceous species, two groups were differentiated: species with similar densities between the DU and the secondary forest and species with higher density in the DU. In the DU, the similarity between the floristic composition of the seedbank and the flora surveyed in 2008 was high, but decreased in subsequent years. The species present in the seedbank of agroforestry systems are highly influenced by the secondary forest, but provide little information about the floristic composition that will arise in the future. 相似文献