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71.
A major challenge for the management of gene banks is the maintenance of good seed health in the collections. Large germplasm collections 10 000 accessions often have been acquired from different sources over a range of dates, may differ in germination at time of deposition in the gene bank, and may have genetic differences in seed longevity. The major storage variables affecting seed longevity are temperature and seed moisture content. Two varieties of each pea(Pisum sativus L.), lentil(Lens culinaris Medikus subsp. culinaris), and chickpea(Cicer arietinum L.), were stored at three temperatures; 40, 20, and 2°C, each with three seed moisture levels of 10.9–13.8%(high), 7.9–10.3%(medium), and 7–7.8%(low), in the Australian Temperate Field Crops Collection gene bank. Seed longevity at a given storage period was estimated by the corresponding germination percentage for each treatment. This paper is an interim report on seed viability decline in the first seven years of this seed longevity study, in which viability decline towards zero was almost completed in the three seed moisture treatments at 40°C and the 20°C high seed moisture treatment, but had not declined in the other treatments. Seed longevity positively responded to a reduction in temperature and then to a reduction in seed moisture. The number of days in storage for seed germination decline to 85%(p85), and to 50%(p50) for mean seed viability, are reported by storage/varietal treatment. Both p85 and p50 showed significant inverse linear responses with seed moisture at 40°C for pea and lentil varieties, with intra-specific variation for pea. This long term trial aims to provide informed timing of seed regeneration for accessions in a gene bank.  相似文献   
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Finding ecologically and economically effective ways to establish matrix species is often critical for restoration success. Wyoming big sagebrush (Artemisia tridentata subsp. wyomingensis) historically dominated large areas of western North America, but has been extirpated from many areas by large wildfires; its re-establishment in these areas often requires active management. We evaluated the performance (survival, health) and economic costs of container and bare-root stock based on operational plantings of more than 1.5 million seedlings across 2 200 ha, and compared our plantings with 30 other plantings in which sagebrush survival was tracked for up to 5 yr. Plantings occurred between 2001 and 2007, and included 12 combinations of stock type, planting amendment, and planting year. We monitored 10 500 plants for up to 8 yr after planting. Survival to Year 3 averaged 21% and was higher for container stock (30%) than bare-root stock (17%). Survival did not differ among container-stock plantings, whereas survival of bare-root stock was sometimes enhanced by a hydrogel dip before planting, but not by mycorrhizal amendments. Most mortality occurred during the first year after planting; this period is the greatest barrier to establishment of sagebrush stock. The proportion of healthy stock in Year 1 was positively related to subsequent survival to Year 3. Costs were minimized, and survival maximized, by planting container stock or bare-root stock with a hydrogel dip. Our results indicate that outplanting is an ecologically and economically effective way of establishing Wyoming big sagebrush. However, statistical analyses were limited by the fact that data about initial variables (stock quality, site conditions, weather) were often unrecorded and by the lack of a replicated experimental design. Sharing consistent data and using an experimental approach would help land managers and restoration practitioners maximize the success of outplanting efforts.  相似文献   
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Feline pancreatitis can be a very difficult disease to diagnose and often requires a combination of clinical suspicion, appropriate physical examination findings, elevations in serum feline pancreatic lipase immunoreactivity, and changes on abdominal ultrasonography consistent with pancreatic disease. The diagnostic difficulties encountered are related to a lack of specific and readily attributable clinical signs in cats. The sensitivity and specificity of the diagnosis of pancreatitis are highest when a combination of tests is utilized; but even when such tests are employed, the diagnosis is still problematic, especially in cats with chronic pancreatitis. Therapy is symptomatic and focuses on maintaining fluid volume, controlling pain and vomiting, preventing infection, and adjusting to changes in the cat's condition as they occur.  相似文献   
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BACKGROUND: Ingestion of wilted red maple leaves by horses can result in severe hemolytic anemia and methemoglobinemia. Little is known about what factors influence the outcome of red maple leaf toxicosis in horses. HYPOTHESIS: Our hypothesis was that physical examination findings, clinicopathologic variables or therapeutic modalities may predict outcome in horses with red maple leaf toxicity. ANIMALS: Horses with red maple leaf toxicosis presented to referral hospitals in the southeast region of the United States. METHODS: A multi-institutional retrospective study was designed to identify factors that predict mortality in horses with red maple toxicosis. RESULTS: Thirty-two horses with red maple toxicosis were identified, 19 of which died. Twenty-nine horses presented with anemia and 24 had clinicopathologic evidence of systemic inflammation. Renal insufficiency was identified in 12/30 (41%) horses. Laminitis (9/28) and colic (13/30) also were identified in horses with red maple toxicosis, but development of these 2 conditions did not have a negative effect on short-term survival. Horses with red maple toxicosis that survived to discharge were likely to have developed pyrexia during hospitalization (P = .030). Horses that were treated with a corticosteroid had a significantly increased likelihood of death (P = .045). There was no significant relationship between initial serum hemoglobin concentration, methemoglobin concentration, or percentage methemoglobin and mortality in this horse series. CONCLUSIONS AND CLINICAL IMPORTANCE: This study suggests that information obtained on initial examination cannot be used to accurately predict survival in horses with red maple toxicosis, but horses that receive corticosteroids are unlikely to survive.  相似文献   
76.
Cholangitis is a common inflammatory disorder of the biliary system in cats. There are two major forms based on the predominate type of inflammatory cell infiltrates: lymphocytic or neutrophilic. Ultrasound is a common imaging modality used in these patients. This retrospective study evaluated the ultrasound examinations of 26 cats with a histologic diagnosis of cholangitis. Most cats with cholangitis had sonographically normal liver size, echogenicity, and normal biliary systems. Statistically significant sonographic changes for cats with cholangitis included hyperechoic liver parenchyma, hyperechoic gallbladder contents, and increased pancreatic size. No statistically significant changes were noted to distinguish lymphocytic and neutrophilic forms of cholangitis. Cats with the sonographic features of diffuse liver hyperechogenicity, gallbladder contents and enlarged pancreas may suggest cholangitis.  相似文献   
77.
Fear and anxiety have been studied extensively in humans and other animals. However, far less attention has been focused on the clinical and ethical implications of nonhuman animals’ susceptibility to psychological disorders. Behavioral signs of psychopathology in nonhuman animals, including our closest phylogenetic relatives, are rarely described as clinical syndromes. In this study, we drew on approaches described in child psychiatry, veterinary medicine, and primatology, to identify behavioral clusters in chimpanzees comparable with human anxiety disorders, such as generalized anxiety disorder and obsessive–compulsive disorder.In phase 1 of this study, we accessed published case reports of 20 chimpanzees subjected to maternal separation, social isolation, experimentation, or similar experiences. We tested the inter-rater reliability of the Diagnostic and Statistical Manual of Mental Disorders (fourth edition; DSM-IV) criteria for generalized anxiety disorder and obsessive–compulsive disorder when applied to chimpanzees in these case studies. Additionally, based on the DSM-IV, veterinary approaches, and ethograms, we defined behaviorally anchored alternative criteria, which proved more reliable than the DSM-IV criteria in phase 1. In phase 2, the new behaviorally anchored criteria were applied to chimpanzees living in wild sites in Africa (n = 196) and those with previous histories of experimentation, orphanage, illegal seizure, or violent human conflict (n = 168) living in sanctuaries. In phase 2, 18% of chimpanzees living in sanctuaries met the set of behaviorally anchored criteria for generalized anxiety disorder, compared with 0.5% of those in the wild (P = 0.036), and 19% of chimpanzees in sanctuaries met the set of behaviorally anchored criteria for obsessive–compulsive disorder, compared with 0% of those in the wild (P = 0.071).Chimpanzees display behavioral clusters similar to anxiety disorders described in humans, underscoring the importance of ethical considerations regarding their use in experimentation and other captive settings.  相似文献   
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A factorially designed set of 3-substituted 2-aryl-4,5,6,7-tetrahydroindazoles was synthesized and their herbicidal properties were evaluated using regression analysis. For optimal activity, the substituent at position 3 should be neither strongly hydrophobic nor hydrophilic and should have a small minimum radius. A study of the mechanism of action indicated that the tetrahydroindazoles are inhibitors of the enzyme protoporphyrinogen oxidase.  相似文献   
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