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141.
Katarzyna Paździor Anna Rapacz Tadeusz Rotkiewicz Andrzej Raś 《Journal of Equine Veterinary Science》2012
Placental retention (retained placenta [RP]) is a serious and common peripartum disease in mares, but the etiology and pathogenesis of RP still remain unclear. The alteration of cell proliferation and apoptosis is considered to be an important factor in RP. Fetal membranes and endometrial biopsies were collected from mares with RP (n = 8) and from control mares (n = 10). The proliferation and apoptosis levels in the chorionic and the endometrial epithelia were assessed by proliferating cell nuclear antigen immunostaining and the terminal deoxynucleotidyl transferase-mediated dUTP nick-end labeling assay, respectively. The study revealed that there was an insignificant decrease in proliferation and a significant increase in apoptosis in the chorionic epithelium from mares with RP. This result excludes a proliferation imbalance from the possible causes of RP. In the area of the nonpregnant horn of the placenta, proliferation was negatively correlated and apoptosis was positively correlated with the degree of fetomaternal anchorage. It was observed that, in all mares with placental retention, the endometrial epithelium (both luminal and glandular) showed decreased proliferation and increased apoptosis, which may indicate a delay in postpartum uterine regeneration. 相似文献
142.
Legocki J Matysiak J Niewiadomy A Kostecka M 《Journal of agricultural and food chemistry》2003,51(2):362-368
Twenty-six compounds, derivatives of amides, hydrazines, hydrazides, hydrazones, and semicarbazides, with a 2,4-dihydroxythiobenzoyl moiety, were synthesized from sulfinyl-bis(2,4-dihydroxythiobenzoyl). The compositions and chemical structures of these compounds were confirmed by IR, (1)H NMR, EI-MS, and elemental analysis. Antifungal properties of chemicals under in vitro conditions against five phytopathogenic fungi were estimated. In vivo studies against Erisiphe graminis were also carried out. The compounds N-substituted with an 2,4-dihydroxythiobenzamide group proved to be the most active. N-2-(1-Cinnamylbenzene ester)-2,4-dihydroxythiobenzamide, under in vitro conditions, showed activity at the level of 80-100% development of most pathogens at a concentration of 20 microg/mL and partially at a concentration of 200 microg/mL. For compounds with -HN-NH- or -NH-N= moiety, weak or no fungistatic properties were found at the concentrations studied. 相似文献
143.
Jalc D Szumacher-Strabel M Potkanski A Cieslak A 《Berliner und Münchener tier?rztliche Wochenschrift》2005,118(9-10):430-435
In vitro anaerobic incubations were used to determine the effect of different oils (LO-linseed, SO-sunflower, FO-fish oil) on trans fatty acid production in rumen fluid and to test if combining of monensin (MON) with the oils affects the interactions on trans fatty acid concentrations in mixed cultures of ruminal microorganisms. Two different sources of rumen fluid were used; the inoculum from the sheep fed hay and barley (80:20%)--the inoculum A and the inoculum from the sheep fed alfalfa and barley (80:20 %)--the inoculum B. The analyses showed that inoculum B contained more short chain fatty acids (SCFA), medium chain fatty acids (MCFA) and saturated fatty acids (SFA) than inoculum A. In contrast, inoculum A contained more unsaturated fatty acids (UFA) than inoculum B. The results show, that the oils affected the biohydrogenation of fatty acids (FA) by increasing the concentration of C18:0 (3-7 times) and trans C18:1 isomers (2-9 times). The concentration of two main intermediates of FA biohydrogenation-- cis 9, trans 11 C18:2 (CLA) and trans 11C18:1 (TVA) were increased with the oils, but FO was more efficient than other plant oils on CLA and TVA production.The monensin treatment had similar effect on FA metabolism as the oil treatment in comparison to unincubated control. The interactions of monensin treatment with the oils were characterized with decrease (LO+MON, SO+MON) or increase (FO+MON) of the proportions of C18:0 and trans C18:1 isomers in comparison to oil treatment.The highest concentrations of two main isomers--CLA,TVA were found in the samples containing fish oil and monensin. In conclusion, fish oil treatment and monensin with fish oil treatment was more efficient than other plant oils in the effect on trans fatty acid production (mainly CLA and TVA) in fermentation fluid in vitro. 相似文献
144.
Andrzej Hoszowski Marian Truszczy
ski 《Comparative immunology, microbiology and infectious diseases》1995,18(4):227-237
The purpose of this paper was (1) comparison of four multi-step methods used for Salmonella isolation from meat- and bone powder; (2) elaboration of a new sensitive method of Salmonella isolation from this product; (3) evaluation of a new solid selective medium (BxLH) described by the authors for Salmonella isolation in comparison to brilliant green agar (BGE) according to Edel and Kampelmacher. The study was carried out on 173 meat- and bone powder samples naturally contaminated with Salmonella oranienburg. The samples were examined for the Salmonella presence by means of four compared methods (Methods 1 to 4). The new method of isolation proposed by the authors (Method 3) proved to be the most effective among all compared for Salmonella recovery. It seems that the superiority of Method 3 in comparison to the other applied was a result of, (1) homogenization of the investigated samples in distilled water before preincubation followed by maintenance at room temperature for 2–4 h; (2) the use of a new selective BxLH agar; (3) the use of multiple plating after selective enrichment. The BxLH medium was shown to be more suitable for Salmonella isolation than BGE agar because of more efficient inhibition of other bacterial growth with simultaneously abundant growth of the Salmonella organisms. The additional advantage offered by BxLH agar was the fact that lactose-positive salmonellas grow as typical representatives of this genus. This enables their identification, in contrast to the situation when lactose containing media are used, where the colonies of such salmonellas are similar to the colonies of, for example, Escherichia coli. 相似文献
145.
Self-incompatibility of almond [Prunus dulcis (Mill.) D.A. Webb] is controlled by the S-locus with 30 described allelic variants. In this study, PCR amplification, cloning and DNA sequence analysis revealed a new S-RNase allele in a Hungarian cultivar, ‘Tétényi bőtermő’. This new allele was labelled as S31. Since S31 is characterized by almost identical intron sizes as S9, consensus PCR was not successful in discrimination of the alleles, even if fluorescently labelled fragments were sized on an automated sequencer. Therefore, an allele-specific forward primer (PdS31-F) was designed to anneal selectively within the second intron of the S31-RNase gene and used in combination with the EM-PC3consRD consensus primer. This allowed for the successful discrimination of S31 from S9. The PdS31-F primer and allele-specific PCR in general might be useful in the identification of different alleles with matching intron sizes that might occur during screening for S-alleles in a more diverse population, e.g. local cultivars from Central Europe to Asia. 相似文献
146.
Stig Einarsson Ylva Brandt Nils Lundeheim Andrzej Madej 《Acta veterinaria Scandinavica》2008,50(1):48
The manifestations of stress, defined as a biological response to an event that the individual perceives as a threat to its homeostasis, are commonly linked to enhanced activity of the hypothalamo-pituitary-adrenal (HPA) axis and the activation of the sympathetic adreno-medullary (SA) system. Activation of the HPA system results in the secretion of peptides from the hypothalamus, principally corticotropin releasing hormone (CRH), which stimulates the release of adrenocorticotropic hormone (ACTH) and beta-endorphin. ACTH induces the secretion of corticosteroids from the adrenal cortex, which can be seen in pigs exposed to acute physical and/or psychological stressors. The present paper is a review of studies on the influence of stressors on reproduction in pigs. The effects of stress on reproduction depend on the critical timing of stress, the genetic predisposition to stress, and the type of stress. The effect of stress on reproduction is also influenced by the duration of the responses induced by various stressors. Prolonged or chronic stress usually results in inhibition of reproduction, while the effects of transient or acute stress in certain cases is stimulatory (e.g. anoestrus), but in most cases is of impairment for reproduction. Most sensitive of the reproductive process are ovulation, expression of sexual behaviour and implantation of the embryo, since they are directly controlled by the neuroendocrine system. 相似文献
147.
Carolina P Sansaloni César D Petroli Jason Carling Corey J Hudson Dorothy A Steane Alexander A Myburg Dario Grattapaglia René E Vaillancourt Andrzej Kilian 《Plant methods》2010,6(1):16
Background
A number of molecular marker technologies have allowed important advances in the understanding of the genetics and evolution of Eucalyptus, a genus that includes over 700 species, some of which are used worldwide in plantation forestry. Nevertheless, the average marker density achieved with current technologies remains at the level of a few hundred markers per population. Furthermore, the transferability of markers produced with most existing technology across species and pedigrees is usually very limited. High throughput, combined with wide genome coverage and high transferability are necessary to increase the resolution, speed and utility of molecular marker technology in eucalypts. We report the development of a high-density DArT genome profiling resource and demonstrate its potential for genome-wide diversity analysis and linkage mapping in several species of Eucalyptus. 相似文献148.
Louise Winblad von Walter Lena Lidfors Andrzej Madej Kristina Dahlborn Eva Hydbring-Sandberg 《Acta veterinaria Scandinavica》2010,52(1):51
Background
Suckling can be a peaceful or vulnerable event for goats and kids, whereas, separation is suggested as stressful. The aim of this study was to investigate physiology and behaviour in these two different situations in dairy goats.Methods
Four studies were performed with seven goats kept with their first-born kid in individual boxes. The goats were videotaped and heart rate and arterial blood pressure were recorded every minute by telemetry from parturition until 24 hours after separation. One to two days after parturition, Study 1 was performed with analyses of heart rate and blood pressure around a suckling. In Study 2, performed 3-5 days after parturition, blood sampling was done before, during and after suckling. Study 3 was performed 4-6 days post partum, with blood sampling before and after a permanent goat and kid separation. In addition, vocalisations were recorded after separation. Blood samples were obtained from a jugular vein catheter and analysed for plasma cortisol, β-endorphin, oxytocin, and vasopressin concentrations. Study 4 was performed during the first (N1) and second nights (N2) after parturition and the nights after Study 2 (N3) and 3 (N4). Heart rate, blood pressure and time spent lying down were recorded.Results
The kids suckled 2 ± 0.2 times per hour and each suckling bout lasted 43 ± 15 s. In Study 1, heart rate and blood pressure did not change significantly during undisturbed suckling. In Study 2, plasma cortisol (P ≤ 0.05 during suckling and P ≤ 0.01 five minutes after suckling) and β-endorphin (P ≤ 0.05) concentrations increased during suckling, but oxytocin and vasopressin concentrations did not change. In Study 3, the goats and kids vocalised intensively during the first 20 minutes after separation, but the physiological variables were not affected. In Study 4, heart rate and arterial blood pressure declined gradually after parturition and were lowest during N4 (P ≤ 0.05) when the goats spent longer time lying down than during earlier nights (P ≤ 0.01 during N1 and N3 and P ≤ 0.05 during N2).Conclusions
Suckling elevated plasma cortisol and β-endorphin concentrations in the goats. The intensive vocalisation in the goats after separation, earlier suggested to indicate stress, was not accompanied by cardiovascular or endocrine responses. 相似文献149.
Non‐specific cellular defence mechanisms of rainbow trout (Oncorhynchus mykiss) in intensive and extensive rearing technologies 下载免费PDF全文
Elżbieta Terech‐Majewska Patrycja Schulz Edyta Kaczorek Andrzej K Siwicki Józef Szarek Krystyna Skibniewska 《Aquaculture Research》2016,47(11):3585-3592
Water as a habitat is highly variable in terms of the physico‐chemical properties. The aim of the studies was to analyze the quality of the technology by evaluating the non‐specific cellular defence potential of rainbow trout (Oncorhynchus mykiss) in diversified intensity culture systems and in different periods of the breeding cycle. The evaluation was conducted in order to establish the scientific basis for the development of principles for recognition of the culture of this species as ‘organic’. Six rainbow trout rearing farms were selected for the studies and divided into two equal groups according to the production technology: farms with a flow through system (with single water usage – OOH) and facilities with multiple water usage via its backflow (re‐circulating system – RAS). The samples for tests were taken from 20 individuals from each fish farm. In all fish that originated both from OOH‐type farms and RAS operations, an increase in the activity of non‐specific cellular immunity in the autumn was observed. Statistically significant reduction in the activity of cellular defensive mechanisms in small (300–500 g) and big (501–850 g) fish occurred on two 3‐OOH and 3‐RAS farms in spring and autumn in 2011. During these periods, the research has shown the presence of Infectious Pancreatic Necrosis Virus (IPNV), which provoked an immune suppression. Based on the obtained results it is concluded that there were no significant differences in the parameters of non‐specific cellular immunity in rainbow trout originating from different farming systems OOH and RAS. 相似文献
150.