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901.
The Blackbuck has suffered rapid decline at the hand of Man during the last half-century, having been exterminated in many areas in which it was formerly plentiful. However, it is said to occur still fairly widely in small populations within its former range in India. In Cholistan Desert in Pakistan ot was indigenous but has disappeared during the last two decades. Where introduced in Texas it is flourishing. Ten Blackbuck were reintroduced from Texas to a small enclosure in the Lal Suhanra Sanctuary, Pakistan, in April 1970, and more stock is expected to be introduced into a near-by larger fenced enclosure of 518·4 ha. Food habits of Blackbuck were studied and the food was estimated in the latter area on 3–8 April 1971. Out of 22 commonly-occuring plant species in the habitat, 19 were eaten. Of these, four or five were favourite food plants of Blackbuck. The quantity of favourite food was estimated and an idea was formed of the order of magnitude of stocking that could be done in this enclosure.  相似文献   
902.
River channel shifting in the deltaic regime is an unabated occurrence. Channel shifting has become one of the concerns as it influences land use/land cover along the riverbank in various ways. For the management of the river, it is indispensable to study the pattern of river course change both in qualitative and quantitative methods. This study is an attempt to understand the pattern of shifting and to quantify erosion and deposition of the river Ganga at upstream and downstream of Farakka Barrage during 1794–2017. The study has been carried out by using various historical maps, aerial photographs, satellite imagery, and remote sensing and GIS technique to understand the dynamic of the river. Over 223 years period shifting of the river accentuates the remarkable oscillation of the river. Perimeter of the river is determined to understand the area covered by the river course in the study area. To evaluate the meandering of the river sinuosity of the river has been computed in this study. The amount of erosion and deposition was calculated in this study by using ArcGIS 10.6. The study found a higher amount of erosion at the east bank where Manikchak, Kaliachak II and Kaliachak III blocks are situated between 1965 and 2017. At the west bank of the river, especially the Rajmahal block, the occurrence of deposition was remarkable during the same period.  相似文献   
903.
A 6‐wk feeding trial was conducted to evaluate the effects of different dietary lipid levels and feeding frequencies on the growth performance, feed utilization, and body composition of juvenile spotted seabass, Lateolabrax maculatus. Two experimental diets were prepared with two different dietary lipid contents, low lipid (7%; LL) and high lipid (14%; HL). Each diet was fed to triplicate groups of fish (5.5 ± 0.01 g) to apparent satiation at three meals per day, two meals per day, one meal per day, and one meal every 2 d, respectively, for 6 wk. Fish growth performance in terms of weight gain (WG) and specific growth rate (SGR) was significantly affected by frequency of feeding, with increasing values as feeding frequency increased up to twice daily, regardless of dietary lipid content. In addition, fish fed the diet with the HL level (14%) showed significantly higher WG and SGR than those fed the LL diet (7%) at all the feeding frequencies tested. Feed efficiency (FE) and protein efficiency ratio (PER) were affected by both dietary lipid level and feeding frequency. FE and PER values were significantly higher in fish fed the HL diet and/or when fish were fed twice or thrice a day. However, daily feed intake and daily energy intake were significantly affected only by feeding frequency and were significantly reduced when the fish were fed only once every 2 d compared with those fed more frequently. Whole‐body moisture content of fish tended to decrease with increasing dietary lipid level and frequency of feeding. In contrast, whole‐body lipid content increased in fish as dietary lipid level and feeding frequency increased. Consequently, we can conclude that feeding spotted seabass twice daily to apparent satiation is acceptable and sufficient to achieve good growth and FE, as fish performance was not significantly enhanced when feeding was increased from two to three times daily.  相似文献   
904.
Winter cover crops are recommended to improve soil quality and carbon sequestration, although their use as green manure can significantly increase methane (CH4) emission from paddy soils. Soil management practices can be used to reduce CH4 emission from paddy soils, but intermittent drainage is regarded as a key practice to reduce CH4 emission and global warming potential (GWP). However, significantly greater emissions of carbon dioxide (CO2) and nitrous oxide (N2O) are expected when large amounts of cover crop biomass are incorporated into soils. In this study, we investigated the effects of midseason drainage on CH4 emission and GWP following incorporation of 0, 3, 6 and 12 Mg/ha of cover crop biomass. Methane, CO2 and N2O emission rates significantly (P < 0.05) increased with higher rates of cover crop biomass incorporation under both irrigation conditions. However, intermittent drainage effectively reduced seasonal CH4 fluxes by ca. 42–46% and GWP by 17–31% compared to continuous flooding. Moreover, there were no significant differences in rice yield between the two water management practices with similar biomass incorporation rates. In conclusion, intermittent drainage and incorporation of 3 Mg/ha of green biomass could be a good management option to reduce GWP.  相似文献   
905.
Dairy farming is vulnerable to global warming and climate change. Improving and maintaining conception rates (CRs) have a paramount importance for the profitability of any dairy enterprise. There is an antagonistic relationship between fertility and milk yield, and intensive selection for milk yield has severely deteriorated reproductive efficiency. Irrespective of geography and husbandry, modern dairy cows experience heat stress (HS) effects leading to fertility declines, but it worsens in tropical climates. The threshold of HS experience among modern dairy cow has lowered, leading to decreased thermal comfort zone. Studies show that this threshold is lower for fertility than for lactation. HS abatement and robustness response to lactation yield lead to negative energy balance, and cow's reproductive requirements remain unfulfilled. The adverse effects of HS commence from developing oocyte throughout later stages and its fertilization competence; the oestrus cycle and oestrus behaviour; the embryo development and implantation; on uterine environment; and even extend towards foetal calf. Even cows can become acyclic under the influence of HS. These harmful effects of HS arise due to hyperthermia, oxidative stress and physiological modifications in the body of dairy cows. Proper assessment of HS and efficient cooling of dairy animals irrespective of their stage of life at farm is the immediate strategy to reduce fertility declines. Other long- and short-term mitigation strategies to reduce fertility declines during HS include feeding care, reducing disease and mastitis rates, using semen from cooled bulls, timed artificial inseminations (AI), allied hormonal interventions and use of embryo transfer technology. Ultimate long-term solution should be well-planned breeding for fertility improvement and HS tolerance.  相似文献   
906.
907.
Maropitant is a neurokinin 1 receptor (NK1R) antagonist that is clinically used as a new anti-emetic drug for dogs. Substance P (SP) and its receptor NK1R are considered to modulate gastrointestinal peristalsis. In addition, SP works as an inflammatory mediator in gastrointestinal diseases. Aim of this study is to clarify the effects of maropitant on intestinal motility and inflammation in mice. Ex vivo examination of luminal pressure-induced intestinal motility of whole intestine revealed that maropitant (0.1–10 µM) increased frequency of contraction, decreased amplitude of contraction and totally inhibited motility index in a concentration-dependent manner. We measured intestinal transit in vivo by measuring transportation of orally administered luminal content labeled with phenol red. Our results demonstrated that maropitant (10 mg/kg, SC) delayed intestinal transit. Geometric center value was significantly decreased in maropitant-treated mice. Anti-inflammatory effects of maropitant against leukocytes infiltration into the intestinal smooth muscle layer in post-operative ileus (POI) model mice were measured by immunohistochemistry. In POI model mice, a great number of CD68-positive macrophages or MPO-stained neutrophils infiltrated into the inflamed muscle region of the intestine. However, in the maropitant treated mice, the infiltration of leukocytes was not inhibited. The results indicated that maropitant has ability to induce disorder of intestinal motility in mice, but has no anti-inflammatory action in the mouse of a POI model. In conclusion, in mice, maropitant induces disorder of intestinal motility in vivo.  相似文献   
908.
Pharmacokinetic (PK) parameters of marbofloxacin (MRFX) in Korean cattle, Hanwoo, were determined following its intravenous (i.v.) or intramuscular (i.m.) administration at a dose of 2 mg/kg. Area under the curve (AUC0–24 hr), half-life (t1/2) and total body clearance (CLB) of i.v. MRFX were 6.87 hr∙µg/ml, 2.44 hr and 0.29 l/kg∙hr, respectively, and the corresponding values for i.m. administration of MRFX were 5.07 hr∙µg/ml, 2.44 hr and 0.39 l/kg∙hr. The suggested optimal doses of MRFX in Hanwoo cattle, calculated by integration of PK data obtained in the present study and previously reported minimum inhibitory concentration (MIC) for MRFX against susceptible (MIC ≤1 µg/ml) and intermediate (MIC ≤2 µg/ml) pathogenic bacteria, were 2.1 and 4.2 mg/kg/day by i.v. route and 3.9 and 7.8 mg/kg/day by i.m. route.  相似文献   
909.
We evaluated the phenology and litterfall dynamics of the mangrove Bruguiera gymnorrhiza (L.) Lamk along the Okukubi River, Okinawa Island, Japan. Over 3 years, this species showed the highest litterfall of leaves and stipules in summer and the lowest litterfall in winter. From Kendall’s coefficient of concordance, the monthly changes in leaf, stipule, and branch were strongly and significantly concordant among years. Leaf and stipule litterfall could be governed by monthly maximum wind speed, monthly day length, and monthly mean air temperature. Branch litterfall depended on monthly maximum wind speed and monthly rainfall, and increased exponentially with increasing monthly maximum wind speed. Mean total litterfall was 11.8 Mg ha?1 yr?1, with the largest component being leaf litterfall (65.8 %). Annual leaf litterfall per plot was almost constant regardless of the tree density of the plot. Mean leaf longevity was 18 months. Flower and mature propagule litterfall might be influenced by monthly mean air temperature, monthly day length and monthly mean air temperature. The average development periods from flower buds to flowers and flower buds to mature propagules were 1 and 8 months, respectively. Except for leaf and branch, all vegetative and reproductive organ litterfall had clear annual cycles. B. gymnorrhiza showed a positive correlation between leaf production and reproductive organ production.  相似文献   
910.
Community forest management (CFM) has received increasing worldwide attention from governments, researchers and educational institutions over the past two decades. Many governments, especially in developing countries, have prioritized CFM over traditional forest management systems. In Thailand, CFM is not recognized by the legal system; however, there are de facto CFM practices under common property resource regimes. CFM has in essence been practiced here for hundreds of years by local people, and represents an important aspect of Thai culture. This study aims at evaluating CFM in Thailand in the context of sustainable development. To meet the objective, the study gathered information through focus group discussions with various stakeholders: academics, Forest Department staff, and members of the Chang Tok Tay community forests. From the study, it emerged that forest resources are critical for the livelihoods and survival of rural people, and so they have protected forests to ensure sustainable livelihoods. This study identified that prospects for sustainable CFM in Thailand are bright because: (i) community members are highly motivated and are sufficiently interested to protect trees because they are well aware that their livelihoods are under threat from depleting forests; (ii) tradition and culture of rural people support their relation with nature; (iii) non-timber forest products (NTFPs) play a crucial role in local livelihoods for subsistence and necessitate protection of the forest watershed, which is vital to support their occupations; (iv) spiritual rituals such as those where Buddhist monks bind yellow cloth on trees play a vital role in protecting trees, something rare in other countries. The study further identified various hindrances to achieve sustainable CFM: (i) legal support for CFM is absent; (ii) the Royal Forest Department (RFD) cannot transfer appropriate technology to community people due to lack of legal support; (iii) scope for developing effective strategies for sustainable CFM by combining traditional knowledge with existing scientific knowledge is limited; (iv) a formal institutional arrangement for CFM does not exist; and (v) community members’ access to the hard technology of CFM is limited. Therefore, in addition to legalizing CFM, a formal institutional framework for elaboration, implementation and control of CFM is essential to achieve sustainable CFM in Thailand.  相似文献   
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