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21.
Gómez NV Castillo VA Gisbert MA Pisano P Mira G Fontanals A Blatter MF 《Veterinary immunology and immunopathology》2011,143(3-4):332-337
Feline immunodeficiency virus (FIV) is a lentivirus that causes a progressive disruption of immune function in cats. The neuroendocrine and immune systems communicate bidirectionally, mediated by cytokines such as tumour necrosis factor-α (TNF), several interleukins (IL-1, IL-6, IL-10), and through signals induced by the ratio of IL-10 to IL-12. FIV can affect both pituitary adrenal and thyroid axis function. Twenty FIV-infected cats in similar stages of the disease were evaluated for six months. A cross-sectional study in which the twenty cats were divided into two groups was performed. Ten were treated with Zidovudine (ZDV: 5mg/kg/d, PO, q12h, for six months) and 10 were untreated. Plasma concentrations of adrenocorticotropic hormone (ACTH), cortisol, T4, FT4, T3, IL-10, IL-12 and viral load (VL) were evaluated after six months. ACTH was found in significantly lower concentrations (p<0.0001) in the treated group whereas cortisol did not show significant differences between the two groups. Both T4 and FT4 had high values in untreated individuals (p<0.001) compared with Zidovudine treated cats. T3 did not show significant differences between the two groups. Both IL-10 and IL-12 were found in significantly higher concentrations in ZDV treated cats (p<0.001). By contrast, the IL10/IL-12 ratio values were significantly lower in untreated cats. Viral load was significantly lower in the treated cats after six months of therapy, compared with values detected pre-treatment (p<0.002). Untreated cats showed a significant increase of VL (p<0.04) compared with the values at the beginning of the study. In treated cats, VL showed lower numbers of viral copies than in untreated cats (p<0.01). In summary, Zidovudine treatment appeared to contribute to the normalization of both the adrenal and thyroid axes. This effect could be attributed to the decrease observed in VL, resulting in a change in cytokine patterns. 相似文献
22.
Antonio López-Piñeiro Damaso Cabrera Ángel Albarrán David Peña 《Journal of Soils and Sediments》2011,11(5):771-782
Purpose
Terbuthylazine is one of the most common herbicides used to control weeds in olive groves. Application of two-phase olive mill waste (OW) to soils may play a fundamental role in the management of leaching losses of pesticides, especially in Mediterranean areas where soils are characterized by low organic matter levels. We evaluated the impact of OW amendments on the sorption–desorption, degradation, leaching, and persistence of the herbicide terbuthylazine in a representative olive grove soil from Portugal. 相似文献23.
A field experiment was conducted to examine the effect of drip irrigation using wastewater from a table olive industry on
physiological, nutritional and yield parameters of olive trees (Olea europaea L.). Very limited information, if any, exists, on the potential of recycling this kind of wastewater in agriculture. Two
types of wastewater were used in the experiment, the first with SAR and EC values of 12–56 and 3.5–4.2 dS m−1, respectively, and the second 73–90 and 4.3–6.0 dS m−1. In general, this kind of wastewater has a highly variable composition and SAR values that are too high for agricultural
purposes. Olive trees rapidly responded to wastewater application. Compared to the control (fresh water), the more saline
wastewater caused important decreases in leaf water potential, stomatal conductance to H2O and the photosynthesis rate after only 15 days of irrigation, the reduction being more pronounced after 2 months of irrigation.
This treatment also caused a rapid, significant reduction in leaf N concentration, as compared with the N level in the trees
before irrigation. Both types of wastewater significantly reduced olive yield, compared to that obtained in the control. These
results indicate that this kind of wastewater is unsuitable for application to olive orchards under irrigation.
Received: 16 August 1999 相似文献
24.
Camila Arroyo‐Salvo Francisco Sanhueza Fernanda Fuentes Favin Treuln María Elena Arias Paulina Cabrera Mauricio Silva Ricardo Felmer 《Reproduction in domestic animals》2019,54(2):184-194
Conventional in vitro fertilization has not yet been implemented in the equine species. One of the main reasons has been the inability to develop a culture medium and incubation conditions supporting high levels of stallion sperm capacitation and hyperactivation in vitro. Although different culture media have been used for this purpose, human tubal fluid (HTF) medium, widely used in the manipulation of human and mice gametes, has not been reported so far in stallion sperm culture. The first part of this study aimed to compare HTF and Whitten's media on different stallion sperm quality and capacitation variables. Additionally, the effect of procaine, aminopyridine and caffeine in both media was evaluated on sperm motility parameters at different incubation times. Integrity and destabilization of the plasma membrane were evaluated by merocyanine 540/SYTOX Green (MC540), mitochondrial membrane potential (?Ψm) using tetramethylrhodamine methyl ester perchlorate (TMRM), acrosome membrane integrity by PNA/FITC and tyrosine phosphorylation by P‐tyrosine mouse mAb conjugated to Alexa Fluor® by flow cytometry. Motility parameters were evaluated using the integrated semen analysis system (ISAS®). We found no differences between Whitten's and HTF media and incubation time in terms of sperm viability, uninduced acrosome membrane damage or mitochondrial membrane potential at 30‐ and 120‐min incubation. Membrane fluidity (MC540) increased in both media at 30‐ and 120‐min incubation compared to noncapacitating conditions. Similarly, tyrosine phosphorylation increased in both media in capacitating conditions at 2‐ and 4‐hr incubation compared to noncapacitating conditions. Although procaine showed the best result in terms of sperm hyperactivated motility in both media, aminopyridine also showed parameters consistent with the hyperactivation including an increase in curvilinear velocity and decrease in straightness. In conclusion, HTF medium and aminopyridine equally support capacitation‐related parameters in stallion sperm. 相似文献
25.
José Valero Galván Jesús J. Jorrín Novo Augusto Gómez Cabrera David Ariza Juan García-Olmo Rafael Ma Navarro Cerrillo 《European Journal of Forest Research》2012,131(4):893-904
We have studied in this work the natural variability in Holm oak (Quercus ilex subsp. ballota) by analyzing acorn morphometry and chemical composition in 13 populations from the Andalusia region (southern Spain). Acorn morphometry showed statistic significant differences between the populations with a higher acorn weight, length, and diameter in the northern provenances (TJA, GSE, CTH, CHU, APS, and PCO), while the Southern provenances (RMA, SAA, CCO, BCA, and SCA) showed lower value that even decreased with the altitude. Acorn chemical composition also showed statistic significant differences between populations. Morphometry and chemical composition data were subjected to clustering analysis, and two major clusters were detected. This analysis showed that northern populations (CTH, TJA, SCA, CHU, PCO, GSE, and APS) showed a tendency to present values highest in acorn weight (5.42?g vs. 3.21?g); acorn length (37.21?mm vs. 28.73?mm); acorn diameter (16.12?mm vs. 13.79?mm); ash (1.88% vs. 1.55%); protein (4.82% vs. 4.38%); fat (12.55% vs. 9.92%); and oleic acid (66.93 vs. 66.4%). On the contrary, Southern populations (SSA, VJA, CCO, BCA, RG, and RMA) showed a tendency to present values lowest in sugar (10.28% vs. 11.25%); energy (20,076.71?kJ/kg vs. 20,149.26?kJ/kg); palmitic (16.11% vs. 16.39%) and linoleic acids (13.07% vs. 13.11%). The populations studied here seemed to integrate acorn morphology and chemical composition related to environmental conditions of the original provenances. These data have provided biochemical markers that help establish phylogenic associations between populations and also reveal potentially account as an alternative source for dietary nutrition. 相似文献
26.
Santana M Batista M Alamo D Cabrera F González F Gracia A 《Reproduction in domestic animals》2012,47(3):e43-e46
The influence of sexual stimulation and human chorionic gonadotrophin (hCG) administration on plasma testosterone concentrations was assessed in five male Beagles. Each dog was exposed to three experimental treatments: C treatment (Control, no stimulation), hCG treatment (dogs were SC injected with 1000 IU of hCG) and sexually stimulated (SS) treatment where semen was collected from the males. All dogs were exposed to all treatments, one per week for three consecutive weeks, with a 1 week of rest between treatments. Blood samples were taken with the same time intervals (0, 10, 30, 60 and 120 min) relative to treatments. Plasma testosterone concentrations were determined with a solid-phase I(125) radioimmunoassay. In the control treatment, the testosterone plasma levels did not show significant changes throughout the tested period (mean values ranging between 2.8 and 4.7 ng/ml); the hCG group presented a significant increase (p < 0.05) in plasma testosterone levels 30 min after hCG administration and had the highest value (8.7 ng/ml) at 120 min post-hCG. Finally, the SS group revealed a slight reduction in testosterone concentration immediately after ejaculation, but the values remained nearly unaltered until 120 min after semen collection. When the groups were compared, the hCG group showed higher plasma testosterone values (p < 0.05) than did the C and SS groups, starting at 30 min and continuing until the end of sampling. This study demonstrates that sexual stimulation associated with semen collection does not produce transitory modifications in plasma testosterone concentrations. 相似文献
27.
28.
The nematode Lagochilascaris minor was collected from subcutaneous abscesses on the face and neck of three female cats aged 8 months, and 1 and 2 years. These cats were born in the Department of Maldonado, Uruguay. Female and male nematodes were 10.1-14.4 and 10.0-14.3mm long, respectively. The lips were one dorsal lip and two subventral lips separated from the body by a deep post-labial groove, and were separated from each other by triangular interlabial projections. The width of the lips was almost equal to the width of the post-labial collar. The vulva was near the middle of the female body. The eggs were oval or spherical and measured 0.059-0.073 mm long and 0.045-0.065 mm wide. Irregular-shaped pits were on the egg surface; 20-32 pits were around the equator of the eggs. The male posterior region was ventrally curved. Each spicule was about three quarters of the ejaculator duct length. From these findings, the nematodes were identified as L. minor. We believe this is the first report of its infection in Uruguay. 相似文献
29.
30.
N. D. Ananyeva T. S. Demkina W. J. Jones M. L. Cabrera W. C. Steen 《Biology and Fertility of Soils》1999,29(3):291-299
Non-tilled and tilled plots on a spodosol (Corg 0.65–1.70%; pH 4.1–4.5) and a mollisol (Corg 3.02–3.13%, pH 4.9–5.3), located in the European region of Russia, were investigated to determine variances in soil microbial
biomass and microbial community composition. Continuous, long-term management practices, including tillage and treatment with
inorganic fertilizers or manure, were used on the spodosol (39 years) and mollisol (22 years). Total microbial biomass (Cmic), estimated by the substrate-induced respiration (SIR) method, and total fungal hyphae length (membrane filter technique)
were determined seasonally over a 3-year period. Long-term soil management practices (primarily tillage and fertilizer application)
led to decreases in total microbial biomass (80–85% lower in spodosol and 20–55% lower in mollisol), decreases in the contribution
of Cmic to Corg (2.3- to 3.5-fold lower in spodosol and 1.2- to 2.3-fold lower in mollisol), and 50–87% decreases in total fungal hyphae
length compared to non-tilled control plots. The contribution of fungi to total SIR in virgin mollisol and fallow spodosol
plots was approximately 30%. However, the contribution of fungi to SIR was approximately two times greater in tilled spodosol
plots compared to a fallow plot. In contrast, the contribution of fungi to SIR in tilled plots of mollisol was less (1.4–4.7
times) than for a virgin plot. In summary, long-term soil management practices such as tillage and treatment with organic
or inorganic fertilizers are important determinants of soil microbial biomass and the contribution of fungi to total SIR.
Received: 28 April 1998 相似文献