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A. M. Orsi S. M. M. Matheus E. A. Gregorio C. C. L. Beu 《Anatomia, histologia, embryologia》1998,27(4):215-218
Morphological investigations of the epithelial cell types that line the ductuli efferentes (DE) of black isogenic mice confirm absorption of the luminal fluid phase by endocytosis as the main function of ductuli efferentes (DE) in this species. Furthermore, all the histochemical and ultrastructural observations on the DE epithelial histoarchitecture indicate other cellular functions such as exocytosis and probably secretion, including an aprocrine secretory process. 相似文献
84.
High-quality seedlings are a prerequisite for successful forestry and agroforestry expansion in developing countries. Unfortunately, in the central Philippines, as supplies of timber from native forest have diminished in recent years, the expansion in planting of timber trees has been retarded by sub-optimal production of seedlings from small-scale nurseries. To address this problem, an extension program supported by the Australian Centre for International Agricultural Research (ACIAR) has attempted to improve the quality of seedlings produced in home nurseries, by assisting smallholders to raise and out-plant seedlings. A complementary program undertaken as part of the Community Agricultural Technology Program (CATP) has attempted to provide community workers and managers of small-scale nurseries with the benefit of recent ACIAR nursery research. Extended assistance in the ACIAR program addressed smallholders’ low self-efficacy in nursery technology and was successful in assisting them to grow high quality seedlings. A limited program of assistance was relatively unsuccessful. Evaluation of the CATP program showed that prior to the training, CATP participants were unfamiliar with some aspects of basic nursery technology. Consequently, they may have been unable to provide competent advice to smallholders. This implies that—as with the ACIAR training—extended training and follow-up assistance may be the key to improving the quality of seedlings for forestry and agroforestry expansion in the central Philippines. 相似文献
85.
Encarna Casas-Díaz Ignasi Marco Jorge R. López-Olvera Gregorio Mentaberre Santiago Lavín 《Veterinary journal (London, England : 1997)》2010,183(3):332-336
Capture and restraint can induce stress in wild animals and tranquilizers may be beneficial in preventing some of the more adverse effects. A short-acting neuroleptic agent (acepromazine) was assessed in 25 Spanish ibexes (Capra pyrenaica) captured by drive-net. The animals were divided into a control group (14 ibexes) and a treated group (11 ibexes). Heart rate and rectal temperature, as well as haematological and biochemical parameters, were used to evaluate the effects of tranquilization during 3 h of restraint. A reduction in rectal temperature, red blood cell count, packed cell volume, haemoglobin concentration, white blood cell count, lymphocytes, neutrophils, activities of creatine kinase, aspartate aminotransferase, alanine aminotransferase, lactate dehydrogenase, and concentrations of urea, total bilirubin and potassium in the treated group, suggested that acepromazine decreased signs of stress in Spanish ibex following drive-net capture. 相似文献
86.
Gregorio I. Gavier-Pizarro Volker C. Radeloff Susan I. Stewart Cynthia D. Huebner Nicholas S. Keuler 《Landscape Ecology》2010,25(10):1505-1518
Forests throughout the US are invaded by non-native invasive plants. Rural housing may contribute to non-native plant invasions
by introducing plants via landscaping, and by creating habitat conditions favorable for invaders. The objective of this paper
was to test the hypothesis that rural housing is a significant factor explaining the distribution of invasive non-native plants
in temperate forests of the Midwestern US. In the Baraboo Hills, Wisconsin, we sampled 105 plots in forest interiors. We recorded
richness and abundance of the most common invasive non-native plants and measured rural housing, human-caused landscape fragmentation
(e.g. roads and forest edges), forest structure and topography. We used regression analysis to identify the variables more
related to the distribution of non-native invasive plants (best subset and hierarchical partitioning analyses for richness
and abundance and logistic regression for presence/absence of individual species). Housing variables had the strongest association
with richness of non-native invasive plants along with distance to forest edge and elevation, while the number of houses in
a 1 km buffer around each plot was the variable most strongly associated with abundance of non-native invasive plants. Rhamnus cathartica and Lonicera spp. were most strongly associated with rural housing and fragmentation. Berberis thumbergii and Rosa multiflora were associated with gentle slopes and low elevation, while Alliaria petiolata was associated with higher cover of native vegetation and stands with no recent logging history. Housing development inside
or adjacent to forests of high conservation value and the use of non-native invasive plants for landscaping should be discouraged. 相似文献
87.
Liz Ota John Herbohn Steve Harrison Nestor Gregorio Vera Lex Engel 《Agroforestry Systems》2018,92(6):1597-1609
Systematic mapping studies provide a snapshot of the literature based on systematic literature searches. In this systematic mapping study, the original research that links reforestation and livelihoods in the tropics was mapped and analysed to identify the trends, biases and gaps in the literature. In total, 339 papers from 92 journals were identified. Agroforestry Systems was the journal in which articles were most frequently published, and Cameroon and Indonesia the most frequently studied countries. The greatest number of authors came from the USA, and authors were most commonly affiliated with ICRAF. A limited collaboration between research groups in the tropical regions was identified. Anthropology and Social Sciences were the most frequent areas of research, especially in Africa. Latin America had more technical studies and more publications discussing payment for environmental services than the other regions. Based on the temporal analysis of the main terms in abstracts of the publications included, it was found that agriculture-related terms and terms related to the human component in the landscape were consistently prevalent in the literature relating reforestation and livelihoods throughout time. Agroforestry systems were especially important in small-scale reforestation and livelihoods. Trends, biases and gaps were discussed. Broader cooperation between tropical regions and between clusters of authors would be beneficial for research and practice. 相似文献
88.
Alberto Arencibia DVM PhD Jose M. Vazquez DVM PhD Juan A. Ramirez MD PhD Gregorio Ramirez DVM PhD Jose M. Vilar DVM Miguel A. Rivero DVM Santiago Alayon MD Francisco Gil DVM PhD 《Veterinary radiology & ultrasound》2001,42(5):405-408
The purpose of this investigation was to define the magnetic resonance (MR) imaging appearance of the brain and associated structures of the equine head. MR images were acquired in oblique dorsal (T2-weighted), sagittal (T1-weighted), and transverse planes (T2-weighted), using a magnet of 1.5 Tesla and a human body coil. Relevant anatomic structures were identified and labeled at each level. The resulting images provided excellent anatomic detail of the cranioencephalic structures. Annotated MR images from this study are intended as a reference for clinical imaging studies of the equine head, specially in the diagnosis of brain diseases in the horse. 相似文献
89.
Jay R. Rooker David H. Secor Vincent S. Zdanowicz Gregorio De Metrio Lidia Orsi Relini 《Fisheries Oceanography》2003,12(2):75-84
Chemical signatures in the otoliths of teleost fishes represent natural tags that may reflect differences in the chemical and physical characteristics of an individuals' environment. Otolith chemistry of Atlantic bluefin tuna (Thunnus thynnus) was quantified to assess the feasibility of using these natural tags to discriminate juveniles (age 0 and age 1) from putative nurseries. A suite of six elements (Li, Mg, Ca, Mn, Sr and Ba) was measured in whole otoliths using solution‐based inductively coupled plasma mass spectrometry. Otolith chemistry of age‐1 T. thynnus collected from the two primary nurseries in the Mediterranean Sea and western Atlantic Ocean differed significantly, with a cross‐validated classification accuracy of 85%. Spatial and temporal variation in otolith chemistry was evaluated for age‐0 T. thynnus collected from three nurseries within the Mediterranean Sea: Alboran Sea (Spain), Ligurian Sea (northern Italy), and Tyrrhenian Sea (southern Italy). Distinct differences in otolith chemistry were detected among Mediterranean nurseries and classification accuracies ranged from 62 to 80%. Interannual trends in otolith chemistry were observed between year classes of age‐0 T. thynnus in the Alboran Sea; however, no differences were detected between year classes in the Tyrrhenian Sea. Age‐0 and age‐1 T. thynnus collected from the same region (Ligurian Sea) were also compared and distinct differences in otolith chemistry were observed, indicating ontogenetic shifts in habitat or elemental discrimination. Findings suggest that otolith chemistry of juvenile T. thynnus from different nurseries are distinct and chemical signatures show some degree of temporal persistence, indicating the technique has considerable potential for use in future assessments of population connectivity and stock structure of T. thynnus. 相似文献
90.
Linghe Zeng James A. Poss Clyde Wilson Abdel-Salam E. Draz Glenn B. Gregorio Catherine M. Grieve 《Euphytica》2003,129(3):281-292
The use of physiological characters as selection criteria in salt tolerance breeding requires the identification of the contribution
each individual character makes to salt tolerance. Rice genotypes were evaluated for salt tolerance in terms of grain yield
and physiological characters. Plants of twelve genotypes were grown in sand tanks in a greenhouse and irrigated with Yoshida
nutrient solution. Sodium chloride and calcium chloride (5:1 molar ratio) were added at two concentrations to give moderate
(4.5 dS m-1) and high (8.3 dS m-1) salinity treatments. One set of plants was harvested at 635 °Cċd (accumulative thermal time) after planting to determine LAI and mineral ion concentrations. Another set of plants was
allowed to grow to maturity. High genotypic diversity for LAI and shoot ion contents was observed. LAI contributed the most
to the variation of the grain yield under salt stress. Significant
correlations between LAI and yield components in both salt-tolerant and-sensitive genotypes further confirmed the significant
contribution of LAI to grain yield. K-Na selectivity increased with increasing salinity. Conversely, Na-Ca selectivity decreased
with increasing salinity. Significant correlations were identified between grain yield and both Na-Ca and K-Na selectivity.
Highly significant (p<0.001) correlations were identified between Na-Ca selectivity and the rankings among genotypes for grain yield. Thus, Na-Ca
selectivity could be one salt tolerance component and an useful selection criterion in screening for salt tolerance.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献