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571.
Mario Giorgi Mehmet Ozdemir Francesco Camillo Duccio Panzani 《Journal of Equine Veterinary Science》2013
Sulpiride (SLP) is an antipsychotic drug used in humans. Although no pharmacokinetic data are available for horses, it is commonly used to encourage ovulation in noncycling mares and to stimulate lactation in adoptive mares. The aim of this study is to assess the pharmacokinetics profile of SLP after intravenous (IV), intramuscular (IM), and oral (PO) administrations in normal horses. Animals (n = 6) were treated with 1 mg/kg SLP, administered by IV, IM, and PO routes according to a randomized crossover design (3 × 3 Latin square). Blood samples (5 mL) were collected at a programmed time and analyzed using a validated with fluorescence detection method. SLP was present at a detectable concentration up to 24 hours postadministration for all routes, except for one animal in the PO group. IV and IM administrations gave similar curves, with an IM average bioavailability of 118.0%. These high values were mainly the result of the profile generated by two horses, in which a secondary concentration peak occurred in the terminal phase of the curve. After PO administration, AUC0-∞, and consequently bioavailability (20.4%), was low. This finding could be owing to the physicochemical features of the drug. Indeed, considering that SLP is a weak base, existing in the ionized form at gastric and physiological pH, it is unsurprising that it is poorly absorbable, especially in horses with a particularly acidic gastric pH. In conclusion, injective routes are definitely preferable to PO dosing because of the low bioavailability using this route. 相似文献
572.
573.
Elliott Jacobson Francesco Origgi Darryl Heard Carol Detrisac 《Journal of veterinary diagnostic investigation》2002,14(6):487-494
Of 120 privately owned captive-bred and wild-collected emerald tree boas (ETBs) (Corallus caninus), 97 died or were euthanatized. Eighteen snakes were necropsied, and tissues were collected from all major organs and processed for light microscopy. Histologic examination demonstrated histiocytic granulomas in the small intestine, heart, and esophageal tonsils of one ETB, small intestine of a second ETB, and in an esophageal tonsil of a third ETB. Within the center of these granulomas, small, basophilic, punctate organisms were demonstrated using hematoxylin and eosin staining. Transmission electron microscopic examination of an intestinal granuloma demonstrated developmental stages of organisms consistent with members of the family Chlamydiaceae. An immunoperoxidase staining technique and 2 different commercially available monoclonal antibodies against chlamydial lipopolysaccharide antigen was used to identify chlamydial antigen in these lesions. Liver of a puff adder (Bitis arietans) with previously reported systemic chlamydiosis served as the positive control. Both monoclonal antibodies stained antigen in these granulomas. Additionally, macrophages within aggregates of lymphoplasmacytic cells in the colon, small intestine, and esophageal tonsils of 3 other ETBs contained antigen. Although both antibodies labeled antigen in serial sections of tissue, a difference in staining intensity was noted. 相似文献
574.
Daily rhythm of tear production in normal horse 总被引:1,自引:0,他引:1
Giuseppe Piccione Claudia Giannetto Francesco Fazio Elisabetta Giudice† 《Veterinary ophthalmology》2008,11(S1):57-60
Objective This study was designed to assess the daily rhythm of tear production in clinically healthy horses, to compare left eye and right eye, and to evaluate the influence of time and gender.
Animal studied For our study 18 horses (nine female and nine male) were subjected to three different light/dark (L/D) schedules: 12/12 L/D cycles, constant light (24/0 L/D) and constant darkness (0/24 L/D).
Procedures In all subjects Schirmer tear tests were performed at 4-h intervals over a 24-h period.
Results A circadian rhythm of tear production was found during the 12/12 L/D period and during constant darkness. Also our results showed a statistical significant difference comparing left eye and right eye, and between gender.
Conclusions Our findings would suggest that the time of tear evaluation is significant in the diagnosis of tear film disorders, and that the difference between the two eyes and the two genders should be taken into consideration during the ophthalmic exam. 相似文献
Animal studied For our study 18 horses (nine female and nine male) were subjected to three different light/dark (L/D) schedules: 12/12 L/D cycles, constant light (24/0 L/D) and constant darkness (0/24 L/D).
Procedures In all subjects Schirmer tear tests were performed at 4-h intervals over a 24-h period.
Results A circadian rhythm of tear production was found during the 12/12 L/D period and during constant darkness. Also our results showed a statistical significant difference comparing left eye and right eye, and between gender.
Conclusions Our findings would suggest that the time of tear evaluation is significant in the diagnosis of tear film disorders, and that the difference between the two eyes and the two genders should be taken into consideration during the ophthalmic exam. 相似文献
575.
Alessandro Troisi Riccardo Orlandi Margherita Maranesi Cecilia DallAglio Gabriele Brecchia Francesco Parillo Cristiano Boiti Massimo Zerani Angela Polisca 《Reproduction in domestic animals》2019,54(2):176-183
In the present study, we evaluated the dynamic changes of intra‐ovarian blood flow, by real‐time colour‐coded and pulsed Doppler ultrasonography, as well as the immunopresence of prostaglandin F2α (PGF2α) receptor (FP) and peripheral plasma progesterone concentrations in pseudopregnant rabbit after PGF2α treatments at either early‐ (4 days) and mid‐luteal (9 days) stages. During the pre‐treatment observation interval of one hour, the ovarian blood flows showed a fluctuating pattern. Independently of luteal stage, PGF2α administration caused a fourfold decline in the blood flow within 40 min that was followed 50 min later by a reactive hyperaemia that lasted several hours, while the resistive index showed an opposite trend. Twenty‐four hour later, the blood flow was one half that measured before PGF2α injection. At day 4 of pseudopregnancy, PGF2α did not affect peripheral plasma progesterone concentrations, but at day 9, it caused functional luteolysis as progesterone levels declined 6 hr later to reach basal values after 24 hr. The changes in the ovarian blood flows of pseudopregnant rabbits receiving PGF2α were accompanied by simultaneous changes in the resistance index. This biphasic response in the blood flow and vascular resistances likely reflects reactive hyperaemia following vasoconstriction. By immunohistochemistry, strong positive immune reaction for FP was detected in the cytoplasm of endothelial cells of ovarian arteries, veins and capillaries. In conclusion, these results suggest that PGF2α could acutely regulate the ovarian blood flow of pseudopregnant rabbits, even if there is no evidence of a blood flow reduction anticipating luteolysis. 相似文献
576.
Vladimíra Oceov Remigius Chizzola Giovanna Battelli Jana Pisarcikova Stefan Faix Francesco Gai Iveta Placha 《Journal of animal physiology and animal nutrition》2019,103(1):204-209
Plant compounds occurring in phytogenic feed additives are involved in different pharmacological activities in the animal organism. Since the digestive tract acts as a first line of defence against foreign compounds, it is necessary to outline its response to dietary supplementation with bioactive plant components. Little information is available on the bioactivity of thymol as the main bioactive compound of Thymus vulgaris L. essential oil (TEO). The main objective of the present study was to provide a detailed view of the concentrations of thymol in plasma and the content of individual intestinal segments (duodenum, jejunum, ileum, caecum and colon) of broiler chickens after 4 weeks of dietary supplementation with different TEO concentrations. 32 one‐day old Ross 308 hybrid broilers were randomly divided into four dietary treatment groups (0.00%, 0.01%, 0.05%, 0.1% w/w of TEO in the diet). Thymol concentrations in the duodenal chyme presented around 7% on average from the thymol amount administered in the feed. A significantly increased thymol amount was observed after 0.1% TEO addition to the diet compared with 0.01% TEO enrichment in the duodenal wall and gut content of jejunum, ileum, caecum and colon (p < 0.05). Thymol levels in the colon were significantly higher than in the ileum and about 1.7 times higher on average than those in the caecum. Significant coefficient of correlation was observed between thymol concentrations in plasma and feed, gut content of all intestinal segments as well as duodenal wall. Our results point to intensive thymol absorption in the initial sections of the digestive tract. In the current study, the role of intestine in biotransformation of thymol was observed, and it would be desirable to investigate whether thymol itself or thymol metabolites are responsible for beneficial effects in intestine. 相似文献
577.
578.
Mannina L Dugo G Salvo F Cicero L Ansanelli G Calcagni C Segre A 《Journal of agricultural and food chemistry》2003,51(1):120-127
The aim of this research is to find if there is direct evidence relating the fatty acid composition of olive oils to specific cultivars grown within a well-limited geographical region. To group olive oils according to their own cultivars,(13)C high-field nuclear magnetic resonance (NMR) and gas chromatography (GC) were used to analyze 60 extra virgin olive oils from the same Italian region (southwestern Sicily) obtained from four monovarietal cultivars. The (13)C NMR spectrum provides information about glycerol triesters of olive oils, i.e., about the acyl composition of major components and about the fatty acids' positional distribution on the glycerol moiety. GC gives the complete fatty acid profile of olive oil samples. Selection of NMR and GC peaks on the basis of their sensitivity to the different cultivars was performed by using multivariate analysis of variance (MANOVA). Principal component analysis, tree clustering analysis, multidimensional scaling (MDS), and linear discriminant analysis (LDA) were then performed on the MANOVA-selected peaks. Results obtained from (13)C NMR and GC techniques combined with the multivariate statistical procedure are in good agreement and prove the usefulness of fatty acids analysis to group the monovarietal olive oils belonging to the same cultivars. Grouping of olive oils according to their cultivars occurs for particular (13)C resonances all belonging to fatty chains in the sn 1,3 position of the glycerol moiety. 相似文献
579.
Ian D. Hogg S. Craig Cary Kevin K. Newsham Byron J. Adams Francesco Frati Diana H. Wall 《Soil biology & biochemistry》2006,38(10):3035-3040
Antarctic terrestrial ecosystems are noted for their relative simplicity and limited trophic structure. In this context, knowledge of biotic interactions in structuring terrestrial soil communities would seem beneficial from a theoretical perspective as well as from a conservation perspective. Unfortunately, although biotic interactions are generally seen as being insignificant in these unique ecosystems, this view is based upon few explicit studies and very little is known of the role that biotic interactions may play. Accordingly, we review our current understanding of these interactions, including analogues from other appropriate ecosystems. On the basis of this review, we conclude that: (1) Antarctic terrestrial systems are predominantly abiotically-driven systems; and (2) a network of manipulative field and laboratory experiments are needed for establishing any role for biotic interactions in structuring Antarctic soil environments. 相似文献
580.
Iacobellis NS Lo Cantore P Capasso F Senatore F 《Journal of agricultural and food chemistry》2005,53(1):57-61
Essential oils extracted by hydrodistillation from fruits of Cuminum cyminum L. and Carum carvi L. were analyzed by gas chromatography (GC) and GC-mass spectrometry (MS). The main components of C. cyminum oil were p-mentha-1,4-dien-7-al, cumin aldehyde, gamma-terpinene, and beta-pinene, while those of the C. carvi oil were carvone, limonene, germacrene D, and trans-dihydrocarvone. Antibacterial activity, determined with the agar diffusion method, was observed against Gram-positive and Gram-negative bacterial species in this study. The activity was particularly high against the genera Clavibacter, Curtobacterium, Rhodococcus, Erwinia, Xanthomonas, Ralstonia, and Agrobacterium, which are responsible for plant or cultivated mushroom diseases worldwide. In general, a lower activity was observed against bacteria belonging to the genus Pseudomonas. These results suggest the potential use of the above essential oils for the control of bacterial diseases. 相似文献