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131.
This article links ecological, social, and cultural data to analyze relationships between wolves and herders in a pastoral setting, the Ikh Nart Nature Reserve, Dornogobi Aimag, Mongolia, an area representative of the broader Gobi-Steppe ecosystem in northern Asia. This article is specifically interested in understanding the contemporary lifestyles of herders in this area, their relationships with wolves, and the perceived and actual risks posed by wolves to both livestock and humans. Data show that herders differed in their views of and actions toward wolves based mainly on the size of herds they managed. But, their cultural stories continue to reflect traditional values and images of wolves and herders. This research argues for an appreciation of cultural contexts in conservation planning, especially in transitional societies.  相似文献   
132.
The nature of the relationship between companion dogs and their owners has important impact on the effect of life for both dog and owner. Identifying factors that affect the dog–owner relationship will assist the understanding of how the successful relationship is achieved and how the less successful relationship is mended, with potential benefits for the welfare of both species. In the present study, we investigated the effect of several dog and owner characteristics, including the personality of the dog, on the dog–owner relationship as measured by the Monash Dog Owner Relationship Scale (MDORS). Data were collected by inviting owners of dogs that had been tested on the Danish Dog Mentality Assessment (DMA) to answer an online questionnaire. We were able to match 421 owner answers with their dogs' DMA test results. The questionnaire consisted of the 28 items of the MDORS, as well as questions about the owners and their dogs. Using factor analysis, 5 dog personality traits could be derived from the dogs' test results on the DMA. The predictive value of questionnaire-based owner and dog variables and the 5 dog personality traits on the dog–owner relationship was tested using multiple linear regressions: 1 for each of the 3 subscales of the MDORS. Overall, the variables investigated only predicted a small proportion of the variance in MDORS scores, and owner characteristics appeared to influence the dog–owner relationship more than dog personality traits did. We found that children in the family and using the dog only for company were negatively associated with the owners' perception of the relationship with their dogs. The only dog characteristics to predict the dog–owner relationship were fearfulness and fear-related behavior problems.  相似文献   
133.
This study hypothesizes that melatonin with exogenous progesterone (CIDR) can improve follicular, luteal, ovarian and uterine haemodynamic of heat-stressed cows. Holstein cows (N = 12) studied for two spontaneous oestrous cycles during winter then divided equally during summer into the CIDR group received CIDR for 7 days and the melatonin group (Mel) received three injections of melatonin (75 mg/head) at the CIDR insertion, removal and ovulation days. Blood samples were collected to assay oestradiol (E2), progesterone (P4) and nitric oxide (NO). On day 0 (Ovulation), Mel had more small follicles (p < .05), higher ipsilateral and contralateral ovarian arteries (Ov.A.) peak systolic velocity (PSV), higher ipsilateral uterine artery (Ut.A.) PSV (p = .031) and blood flow volume (BFV), also Mel elevated contralateral Ut.A. PSV and BFV (p < .0001) but lowered contra Ut.A. pulsatility index (PI, p < .0001), E2 (p < .01) and NO (p < .0001). Mel increased the corpus luteum diameter (CL, p < .001), coloured area (p < .007) and P4 (p < .0001) on day 5 and reduced them (p < .05; p < .01) on Day 14. On day 10, Mel obtained CL diameter (p < .03) and coloured area (p < .002) of spontaneous that was higher than CIDR and decreased P4 (p < .003). Mel increased CL diameter, area and coloured area and decreased them thereafter. Mel increased the ipsilateral ovarian and uterine arteries PSV and BFV before ovulation and until day 8. Mel increased P4 and decreased NO until days 6 and 14. In conclusion, the improvement in follicular, luteal, ovarian and uterine haemodynamic and the decrease of NO production proved our hypothesis Melatonin doses higher than 75 mg/head is recommended to improve the heat-stressed cow's fertility.  相似文献   
134.
ObjectiveTo evaluate the effects and utility of tiletamine–zolazepam–medetomidine (TZM) and ketamine–medetomidine (KM) for anesthesia of Amur leopard cats (Prionailurus bengalensis euptailurus).Study designProspective, randomized experimental trial.AnimalsA total of six female (3.70 ± 0.49 kg) and six male (5.03 ± 0.44 kg; mean ± standard deviation) Amur leopard cats aged 2–6 years.MethodsEach animal was administered four protocols separated by ≥3 weeks. Each protocol included medetomidine (0.05 mg kg–1) combined with tiletamine–zolazepam (1 mg kg–1; protocol MTZLO); tiletamine–zolazepam (2 mg kg–1; protocol MTZHI); ketamine (2 mg kg–1; protocol MKLO); or ketamine (4 mg kg–1; MKHI) administered intramuscularly. At time 0 (onset of lateral recumbency) and 30 minutes, heart rate (HR), respiratory rate (fR), rectal temperature, noninvasive mean arterial pressure (MAP) and hemoglobin oxygen saturation (SpO2) were recorded. Times to onset of lateral recumbency, duration of anesthesia and time to standing were recorded.ResultsOverall, animals were anesthetized with all protocols within 10 minutes, anesthesia was maintained ≥57 minutes, and recovery (time from the first head lift to standing) was completed within 5 minutes. During anesthesia with all protocols, HR, fR, rectal temperature, SpO2 and MAP were 99–125 beats minute–1, 33–44 breaths minute–1, 37.6–39.4 °C, 90–95% and 152–177 mmHg, respectively. No adverse event was observed.Conclusions and clinical relevanceTZM and KM at various dosages resulted in rapid onset of anesthesia, duration of >57 minutes and rapid recovery without administration of an antagonist. Accordingly, all these combinations are useful for anesthetizing Amur leopard cats and for performing simple procedures. However, the low doses of the anesthetic agents are recommended because there was no difference in duration of anesthesia between the dose rates studied.  相似文献   
135.
The role that the environment plays in vector-borne parasite infection is one of the central factors for understanding disease dynamics. We assessed how Neotropical bird foraging strata and habitat preferences determine infection by parasites of the genera Haemoproteus, Plasmodium, Leucocytozoon, and Trypanosoma and filarioids, and tested for phylogenetic signal in these host–parasite associations. We performed extensive searches of the scientific literature and created a database of hemoparasite surveys. We collected data on host body mass, foraging strata, habitat preference, and migratory status, and tested if host ecological traits predict each hemoparasite occurrence and prevalence using a phylogenetic Bayesian framework. Species of Plasmodium tend to infect birds from tropical forests while birds from altitudinal environments are likely to be infected by species of Leucocytozoon. The probability of a bird being infected by filarioid or Trypanosoma is higher in lowland forests. Bird species that occur in anthropic environments and dry habitats of tropical latitudes are more susceptible to infection by species of Haemoproteus. Host foraging strata is also influential and bird species that forage in the mid-high and canopy strata are more prone to infection by species of Haemoproteus and filarioids. We also identified phylogenetic signal for host–parasite associations with the probability of infection of Neotropical birds by any hemoparasite being more similar among more closely related species. We provided a useful framework to identify environments that correlate with hemoparasite infection, which is also helpful for detecting areas with potential suitability for hemoparasite infection due to land conversion and climate change.  相似文献   
136.
Zinc (Zn) deficiency is common among crops grown in the tropics in acid and weathered soils. In response, the use of amino-acids (AAs) to increase the uptake of this nutrient has been increasing dramatically in recent years. Nevertheless, there is a scarcity of results reported on the effect of applying AAs and adequate quantities of Zn on alfalfa grown under tropical edaphoclimatic conditions. Therefore, a greenhouse experiment was conducted with a completely randomized block in a factorial scheme (4×2) of four Zn rates of 0, 4, 8, and 16 mg kg?1) with and without spraying of AAs during the sprouting phase, to study the effects on the shoot dry weight (SDW) yield, nutritional state, physiological parameters, and soil fertility. The harvests were repeated over time (three cuts). The SDW yield was significantly influenced up to a rate of 4.0 mg kg?1 of Zn, after which it stabilized. Independent of the Zn rate, the application of AAs did not influence the SDW yield. Based on the averages for the three cuts, only the Zn rates altered the photosynthesis and chlorophyll content, with no effect of the AAs. The concentrations of Zn in the soil extracted by the Mehlich 1 and diethylenetraminepenta acetic acid (DTPA)- triethanolamine (TEA) methods were strongly and significantly correlated (r = 0.99, P ≤ 0.05) with the Zn rates and the Zn concentrations in the plant tissue. The agronomic, physiological, and zinc use efficiencies diminished with increased Zn rates, while the inverse occurred with the Zn efficiency index.  相似文献   
137.
ABSTRACT

After the rice harvest in Japan, rice straw (RS) is usually cut by combine harvester and incorporated into the soil to improve its fertility. In mixed crop–livestock systems, however, RS is collected and used as livestock feed, and cow dung compost (CDC) is then applied to the soil. This system utilizes the residual organic matter from both rice production and livestock husbandry to make each product. CDC application is also considered to improve the fertility of paddy soil. However, the nutrient input from CDC and the effect of CDC application on soil fertility vary among regions and/or soil types. We compared soil fertility between RS application (RS treatment, avg. 32 years) and RS removal plus CDC application (CDC treatment, avg. 21 years) in 79 paddy fields in Mamurogawa town, Yamagata Prefecture, a cold temperate region of Japan, and measured the nutrient contents in the applied RS and CDC. The total C content of RS was significantly higher than that of CDC, whereas the N, P, K, and Si contents of CDC were significantly higher than those of RS. However, there was no significant difference in paddy soil fertility – as measured by soil organic C, total N, CEC, available N, P, and Si, exchangeable K, Ca, and Mg, base saturation percentage, pH, and bulk density – between the treatments. The soil fertility of most fields was adequate by RS or CDC treatment. Thus, leaving RS in paddy fields or removing it and then adding CDC to the paddy fields has a similar effect in maintaining adequate soil fertility for single rice production or rice–livestock production systems.  相似文献   
138.
In Mongolia, yak (Bos grunniens) are able to live in alpine areas and their products greatly influence the lives of the local people. Increased vigour in hybridized yak and cattle can offer benefits for livestock farmers. However, male hybrids show reproductive defects resulting from spermatogenesis arrest, affecting the conservation and maintenance of dominant traits in the next generation. The underlying mechanisms involved in hybrid cattle–yak infertility have recently been investigated; however, the genetic cause is still unclear. Androgens and androgen receptor (AR) signalling are required for spermatogenesis. We, therefore, evaluated the expression of AR, 3β-hydroxysteroid dehydrogenase (3βHSD) and 5α-reductase 2 (SRD5A2) in Leydig cells to investigate their function in cattle–yak spermatogenesis. Testicular tissues from yaks (1–3 years old) and hybrids (F1–F3, 2 years old) were collected and subjected to immunohistochemistry and image analyses to investigate the expression of each parameter in the Leydig cells. After maturation at 2 years, the expression levels of AR increased and the levels of 3βHSD decreased, but the SRD5A2 levels remained constant in yak. However, the cattle–yak hybrid F2 showed immature testicular development and significantly different expression levels of AR and 3βHSD compared with mature yak. These results suggest that the decreased expression of AR and increased expression of 3βHSD in the Leydig cells of cattle–yak hybrid testes may represent one of the causes of infertility. Our study might help in solving the problem of infertility in crossbreeding.  相似文献   
139.
The increasing frequency and severity of wildfires has led to growing attention to the effects of fire disturbance on soil microbial communities and biogeochemical cycling. While many studies have examined fire impacts on plant communities, and a growing body of research is detailing the effects of fire on soil microbial communities, little attention has been paid to the interaction between plant recolonization and shifts in soil properties and microbial community structure and function. In this study, we examined the effect of a common post-fire colonizer plant species, Corydalis aurea, on soil chemistry, microbial biomass, soil enzyme activity and bacterial community structure one year after a major forest wildfire in Colorado, USA, in severely burned and lightly burned soils. Consistent with past research, we find significant differences in soil edaphic and biotic properties between severe and light burn soils. Further, our work suggests an important interaction between fire severity and plant effects by demonstrating that the recolonization of soils by C. aurea plants only has a significant effect on soil bacterial communities and biogeochemistry in severely burned soils, resulting in increases in percent nitrogen, extractable organic carbon, microbial biomass, β-glucosidase enzyme activity and shifts in bacterial community diversity. This work propounds the important role of plant colonization in succession by demonstrating a clear connection between plant colonization and bacterial community structure as well as the cycling of carbon in a post-fire landscape. This study conveys how the strength of plant–microbe interactions in secondary succession may shift based on an abiotic context, where plant effects are accentuated in harsher abiotic conditions of severe burn soils, with implications for bacterial community structure and enzyme activity.  相似文献   
140.
Green manure cover crops (GMCCs) planting has a potential for mitigating greenhouse gas emissions (GHG) in agroecosystems and provides important ecosystem services, thereby achieving the Sustainable Development Goals (SDGs) stipulated by the United Nations. However, the advantages of cultivating GMCCs on arable land are not widely recognized. For example, in the whole of China, the GMCCs planting area is less than 3.5% of total arable land. The aim of this study is to explore reasons for the low adoption rate of GMCCs planting. Using best–worst scaling (BWS) approach, farmers ranked their preferred conservation practices including three types of GMCC cropping systems. Taking Gansu Province in Northwest China as a case study, a survey with 276 farmers was conducted. The findings indicated that three factors are related to the low adoption rate of GMCCs: 1) farmers preferred improving farmland irrigation facilities and substituting chemical fertilizers with organic rather than planting GMCCs; 2) lack of awareness and understanding of government policy on GMCCs and limited access to training courses; 3) financial support and subsidies from the government are insufficient. This study provides insights and strategic implications for policymakers on how to further promote GMCCs in the future.  相似文献   
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