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91.
Objective— To investigate the feasibility of, and outcome after, laparoscopic adrenalectomy in dogs with unilateral adrenocortical carcinoma.
Study Design— Case series.
Animals— Dogs (n=7) with Cushing's syndrome caused by unilateral adrenocortical carcinoma.
Methods— Laparoscopic adrenalectomy with the dog in lateral recumbency on the unaffected side. Three 5-mm portals (1 laparoscopic portal, 2 instrument portals) were placed in the paralumbar fossa. A fourth instrumental portal (5–12 mm) was placed above the kidney. After dissection and hemostatic control of the phrenicoabdominal vein, the adrenal gland was carefully dissected or when there was capsule fragility, necrotic content was partially aspirated. The remaining glandular tissue was removed through the 12-mm trocar site.
Results— Dogs with unilateral adrenocortical carcinoma (3 right-sided, 4 left-sided) without invasion of the caudal vena cava were successfully operated by laparoscopic approach. There were no significant intraoperative complications; 2 dogs died within 48 hours of surgery because of respiratory complications. Five dogs were discharged 72 hours after surgery, and signs of hyperadrenocorticism disappeared thereafter (survival time ranged from 7 to 25 months).
Conclusions— Laparoscopic adrenalectomy is feasible in dogs with either right- or left-sided adrenocortical carcinoma not involving the caudal vena cava.
Clinical Relevance— When performed by experienced surgeons, laparoscopic adrenalectomy offers a minimally invasive alternative to open laparotomy or retroperitoneal surgery for the treatment of unilateral adrenocortical carcinoma in dogs.  相似文献   
92.
Human (HRSV) and bovine (BRSV) respiratory syncytial viruses (RSV) are two closely related viruses, which are the most important causative agents of respiratory tract infections of young children and calves, respectively. BRSV vaccines have been available for nearly 2 decades. They probably have reduced the prevalence of RSV infection but their efficacy needs improvement. In contrast, despite decades of research, there is no currently licensed vaccine for the prevention of HRSV disease. Development of a HRSV vaccine for infants has been hindered by the lack of a relevant animal model that develops disease, the need to immunize immunologically immature young infants, the difficulty for live vaccines to find the right balance between attenuation and immunogenicity, and the risk of vaccine-associated disease. During the past 15 years, intensive research into a HRSV vaccine has yielded vaccine candidates, which have been evaluated in animal models and, for some of them, in clinical trials in humans. Recent formulations have focused on subunit vaccines with specific CD4+ Th-1 immune response-activating adjuvants and on genetically engineered live attenuated vaccines. It is likely that different HRSV vaccines and/or combinations of vaccines used sequentially will be needed for the various populations at risk. This review discusses the recent advances in RSV vaccine development.  相似文献   
93.
Landscape Ecology - Landscape graphs are widely used to model networks of habitat patches. As they require little input data, they are particularly suitable for supporting conservation decisions...  相似文献   
94.
Forefields of retreating glaciers represent unique opportunities to investigate the initial phases of soil formation and microbial interactions with mineral surfaces. An open question concerns the physical and chemical driving‐factors affecting the establishment of microbial communities in these young ecosystems. In this study we compared the bacterial community structure of six glacier forefield soils belonging to two contrasting bedrock categories (calcareous and siliceous) through T‐RFLP profiling of the 16S rRNA gene. The community profiles were correlated with an array of physical (soil texture, water holding capacity, hours of sunshine, temperature, rainfall and exposure) and chemical (TC, TN, DOC, extractable nutrients and pH) factors using canonical correspondence analysis (CCA). A first comparison of the T‐RFLP profiles suggested that the degree of operational taxonomic unit (OTU) diversity of these soils was similar, and that community structure was dominated by ubiquitous taxa. CCA showed that both physical (e.g. hours of sunshine or rainfall) and chemical factors (e.g. SO2−4 or PO3−4) played an equal role in shaping the soil bacterial communities. OTUs unique to specific sites appeared to be strongly influenced by the climatic regime and by texture. Overall, the community structure of the six glacial forefields showed no clear dependence on the bedrock categories.  相似文献   
95.
Plasma membrane H+-ATPase (PM H+-ATPase) plays a key role in nutrient transport, stress responses and growth. To evaluate proton motive force differences between apical and basal parts of acrotonic 1-year-old shoots of walnut (Juglans regia L. cv 'Franquette') trees, spatial and seasonal changes in PM H+-ATPase were studied in mature xylem tissues. During both the dormancy and growth resumption periods, and in both the apical and basal parts of the stem, PM H+-ATPase activity showed positive correlations with the amount of immunodetectable protein. In spring, at the time of growth resumption, higher activities and immunoreactivities of PM H+-ATPase were found in the apical part of the stem than in the basal part of the stem. In spring, the decrease in xylem sugar concentration reflected the high sugar uptake rate. Our data suggest that PM H+-ATPase plays a major role in the uptake of carbohydrates from xylem vessels during growth resumption. These results are discussed in the context of the acrotonic tendency of walnut shoots.  相似文献   
96.
Otolith microchemistry can provide crucial information to address gaps of knowledge in spatio‐temporal ecology of fish species. However, understanding the seasonal variability of water chemistry and its effect on otolith signatures is needed to interpret fish movements. Otolith multi‐elemental signatures were used to examine the diadromous migration and small‐scale movements of a tropical goby (Sicyopterus lagocephalus) within a watershed in La Réunion Island, Indian Ocean. The elemental ratios Sr:Ca, Ba:Ca and Sr:Ba recorded monthly in the water of nine sampling sites varied between localities and were correlated with otolith signatures, whereas the Mg:Ca signature was not. The incorporation of some trace elements in otoliths was influenced by the size of fish and site where they were caught, reflecting an effect of endogenous and exogenous factors. Despite these sources of variation, the elemental signatures did not overlap for three river sections distributed along the 26‐km‐long watershed. The diadromous migration and fish lifetime movements between these river sections were reconstructed using an original process based on random forest analysis. This approach revealed distinct migratory behaviours after fish entered in the river, with some individuals progressing slowly in the watershed whereas other rapidly reached the upper localities. As adults, S. lagocephalus showed a restricted exploratory behaviour and a strong site fidelity to a particular part of the watershed. The detection of adult movement was typically only between adjacent locations and is possibly explained by shifts in local intraspecific hierarchies and/or displacement during extreme discharge caused by cyclones.  相似文献   
97.
The agricultural sector is often considered to be the largest water consumer and the policy aimed at saving irrigation water exists across Europe. The flip-side of such policy, however, is the disappearance of traditional irrigation canals since farmers are encouraged to turn to drip irrigation and overhead irrigation gradually. Given this, we would like to argue that traditional irrigation canals need to be reexamined. Such canals are not only built aquatic infrastructure, they are also the product of a culture and social relationship with water in the Mediterranean region. Canals form a complex system which is driven by environmental, economic and social factors. Our sociological and environmental research in Provence (and around the Durance basin more specifically) points up how the very dense territorial network of gravity-fed canals is useful in water management, as well as in other shared uses over the long-term. The findings underscore the positive environmental role played by these historical and anthropogenic constructions. They contribute to refilling the aquifer and also act as a valuable environmental good and service (e.g., run-off regulation, biodiversity, landscape, recreation, etc.). Further, several local actors have underscored their role as part of an intangible cultural heritage and as important for the area's economic and social development. Such canals play a central role in sustainable development since beyond their productive role in agriculture, they play a social role (new uses) and an ecological role (as reservoirs for biodiversity and ecological corridors).  相似文献   
98.
99.
In the insect olfactory system, oscillatory synchronization is functionally relevant and reflects the coherent activation of dynamic neural assemblies. We examined the role of such oscillatory synchronization in information transfer between networks in this system. The antennal lobe is the obligatory relay for olfactory afferent signals and generates oscillatory output. The mushroom body is responsible for formation and retrieval of olfactory and other memories. The format of odor representations differs significantly across these structures. Whereas representations are dense, dynamic, and seemingly redundant in the antennal lobe, they are sparse and carried by more selective neurons in the mushroom body. This transformation relies on a combination of oscillatory dynamics and intrinsic and circuit properties that act together to selectively filter and synthesize the output from the antennal lobe. These results provide direct support for the functional relevance of correlation codes and shed some light on the role of oscillatory synchronization in sensory networks.  相似文献   
100.
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