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171.
Although data quality and weighting decisions impact the outputs of reserve selection algorithms, these factors have not been closely studied. We examine these methodological issues in the use of reserve selection algorithms by comparing: (1) quality of input data and (2) use of different weighting methods for prioritizing among species. In 2003, the government of Madagascar, a global biodiversity hotspot, committed to tripling the size of its protected area network to protect 10% of the country’s total land area. We apply the Zonation reserve selection algorithm to distribution data for 52 lemur species to identify priority areas for the expansion of Madagascar’s reserve network. We assess the similarity of the areas selected, as well as the proportions of lemur ranges protected in the resulting areas when different forms of input data were used: extent of occurrence versus refined extent of occurrence. Low overlap between the areas selected suggests that refined extent of occurrence data are highly desirable, and to best protect lemur species, we recommend refining extent of occurrence ranges using habitat and altitude limitations. Reserve areas were also selected for protection based on three different species weighting schemes, resulting in marked variation in proportional representation of species among the IUCN Red List of Threatened Species extinction risk categories. This result demonstrates that assignment of species weights influences whether a reserve network prioritizes maximizing overall species protection or maximizing protection of the most threatened species.  相似文献   
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A 7-year-old gelded Irish sports horse weighing 650 kg was anesthetized on 2 consecutive days for lavage of a septic right radio-carpal joint. On both occasions the endotracheal tube connector, which had been bound in medical tape to produce an airtight seal, functioned as a unidirectional valve during mechanical ventilation, retarding expiration, imposing positive end expiratory pressure (PEEP), and probably continuous positive airway pressure (CPAP). The equipment dysfunction was not identified on either occasion despite close inspection prompted by progressive increases in airway pressure and thoracic distension. Whilst the PEEP and CPAP exerted unexpectedly modest cardiovascular effects and the horse recovered uneventfully on both occasions, the improvisation may have proven fatal in a higher-risk subject.  相似文献   
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OBJECTIVES: To determine associations among infectious pathogens and diarrheal disease in dogs in an animal shelter and demonstrate the use of geographic information systems (GISs) for tracking spatial distributions of diarrheal disease within shelters. SAMPLE POPULATION: Feces from 120 dogs. PROCEDURE: Fresh fecal specimens were screened for bacteria and bacterial toxins via bacteriologic culture and ELISA, parvovirus via ELISA, canine coronavirus via nested polymerase chain reaction assay, protozoal cysts and oocysts via a direct fluorescent antibody technique, and parasite ova and larvae via microscopic examination of direct wet mounts and zinc sulfate centrifugation flotation. RESULTS: Salmonella enterica and Brachyspira spp were not common, whereas other pathogens such as canine coronavirus and Helicobacter spp were common among the dogs that were surveyed. Only intestinal parasites and Campylobacterjejuni infection were significant risk factors for diarrhea by univariate odds ratio analysis. Giardia lamblia was significantly underestimated by fecal flotation, compared with a direct fluorescent antibody technique. Spatial analysis of case specimens by use of GIS indicated that diarrhea was widespread throughout the entire shelter, and spatial statistical analysis revealed no evidence of spatial clustering of case specimens. CONCLUSIONS AND CLINICAL RELEVANCE: This study provided an epidemiologic overview of diarrhea and interacting diarrhea-associated pathogens in a densely housed, highly predisposed shelter population of dogs. Several of the approaches used in this study, such as use of a spatial representation of case specimens and considering multiple etiologies simultaneously, were novel and illustrate an integrated approach to epidemiologic investigations in shelter populations.  相似文献   
176.
Two adult Boxers were evaluated because of chronic dysphagia of several years' duration. Serum creatine kinase activity was high in both dogs, but other hematologic or serum biochemical abnormalities were not detected. Esophagraphy revealed abnormalities of the cricopharyngeal phase of swallowing in both dogs, and electromyography of the pharyngeal and laryngeal muscles revealed complex repetitive discharges, positive sharp waves, and fibrillation potentials characteristic of primary myopathy or neuropathy. Because of the severity of their condition, both dogs were euthanatized. Histologically, mixed-cell infiltrates were seen in sections of the masseter and thyropharyngeal muscles. Results of indirect immunofluorescence staining for proteins associated with dystrophic myopathy were unremarkable, except for decreased staining for integrin alpha7. A diagnosis of chronic inflammatory myopathy was made. The clinical importance of reduced staining for integrin alpha7 could not be determined but was considered to be a result of the myopathy.  相似文献   
177.
Clinical, histopathological and immunological features of exfoliative cutaneous lupus erythematosus, an uncommon generalized exfoliative dermatitis occurring exclusively in German short-haired pointers, were characterized in 25 dogs. The disease affects young adult dogs and its familial incidence strongly suggests a hereditary origin. Lesions were characterized by scaling and alopecia affecting 100 (25/25) and 76% (19/25) of dogs, respectively. Follicular casts were present in 28% (7/25) of dogs. The muzzle, pinnae and dorsum were typically affected. Generalized skin lesions were described in 52% (13/25) of dogs. Systemic signs of pain and lameness affected several dogs. Anaemia and thrombocytopenia were detected in several dogs with a more severe clinical phenotype. The most common histopathological features were hyperkeratosis and a lymphocytic interface dermatitis. Direct immunostaining revealed IgG deposition in the epidermal and follicular basement membrane of 100 (19/19) and 41% (7/17) of dogs, respectively. Circulating antifollicular and antisebaceous gland IgG antibodies were demonstrated by indirect immunostaining in 57% (4/7) of dogs. This disease usually responds poorly to immunosuppressive therapy and it has a guarded prognosis. Where outcome was recorded, 85% (10/12) of dogs were euthanased due to either a failure to respond to, or complications associated with, immunomodulatory therapy. Two affected dogs are in remission and maintained on immunomodulatory dosages of prednisolone. This study demonstrates the existence of a cellular and humoral immune response directed against the epidermal basement membrane of dogs with exfoliative cutaneous lupus erythematosus. Additional studies are required to further characterize the immunological pathogenesis of this disease.  相似文献   
178.
Total extract from the fruit of Szechuan pepper (Zanthoxylum piperitum DC), the volatile components of the extract and a non‐volatile fraction containing alkylamides (NVA fraction) are feeding deterrents for rats. The present study investigated the effectiveness of these natural repellents in prairie voles (Microtus ochrogaster Wagner). Two‐choice feeding trials were conducted during which food‐deprived voles were offered choices between oat‐bran wafers. In Experiment 1, 10 voles were given three sets of feeding trials, each 2 h long. Baseline consumption was established during the first set of two trials by offering a choice between two oat‐bran wafers dipped in ethanol, the control solvent. During the second set of two trials the voles were given a choice between an oat‐bran wafer dipped in ethanol and a wafer dipped in Zanthoxylum extract. During the third set the voles were given a choice between a wafer served on top of a screened dish containing a sample of ethanol and a wafer served on top of a dish containing a sample of extract. In this manner the voles were exposed to volatile compounds emanating from the extract but could not contact it. Wafers dipped in extract were almost completely avoided. The volatile components of extract also significantly reduced food intake. In Experiment 2, habituation to the volatile constituents of extract was examined in 16 Zanthoxylum‐naïve voles. Baseline consumption was established by offering two wafers served on top of screened dishes containing ethanol. This was followed by twelve tests during which a choice between a wafer served above a sample of ethanol and a wafer served above a sample of extract was given. The voles failed to habituate to the volatile components of extract, consistently consuming less of the wafers served above extract. In Experiment 3 a dose‐response curve to Zanthoxylum extract was established, using 12 stimulus‐naïve voles. After baseline consumption was established, the animals were given two tests each, presenting a choice between a control wafer and a wafer dipped in a dilution of extract (0.001–100 g liter?1). Only concentrations of 10 and 100 g liter?1 reduced food intake. In Experiment 4 the effects of the non‐volatile fraction of extract were compared to those of whole extract. Vegetable oil was used as solvent. Eight stimulus‐naïve voles were given two tests with a choice between an oil‐dipped and an extract‐dipped wafer. A second group of eight voles received two tests with a choice between an oil‐dipped and NVA‐dipped wafer. Extract‐dipped wafers were avoided, but the NVA fraction had no effect on food consumption. Copyright © 2004 Society of Chemical Industry  相似文献   
179.
OBJECTIVE: To evaluate a modified Ziehl-Neelsen acid-fast staining technique (mZN), a direct immunofluorescence detection procedure (DIF), and 3 commercial enzyme immunoassays (EIAs) for detection of Cryptosporidium oocysts in fecal specimens from kittens. DESIGN: Prospective study. SAMPLE POPULATION: 416 fecal specimens collected from 104 randomly selected domestic shorthair kittens (8 to 16 weeks of age) that were naturally exposed to Cryptosporidium spp. PROCEDURE: Fresh fecal specimens were collected once daily for 4 consecutive days and processed immediately. Sensitivities of mZN, DIF, and 3 commercial EIAs (EIA-1, EIA-2, and EIA-3) were estimated and compared. RESULTS: EIA-2 had the highest sensitivity on day 1 (89%), followed by EIA-1 (80%), and mZN (72%). EIA-3 had the lowest sensitivity on day 1 (15%). EIA-2, EIA-1, and mZN had similar sensitivities after 2 consecutive fecal examinations (approx 90%). Determination of specificities was compromised by the small number of cats that had negative results for all tests (n = 3). CONCLUSIONS AND CLINICAL RELEVANCE: Results suggest that EIA-2 and EIA-1 had the highest sensitivities when only a single fecal specimen was examined; however, mZN and EIA-1 had similar sensitivities when 2 consecutive fecal specimens were examined. The higher costs of EIA-2 and EIA-1 may be offset by the tests' high sensitivity, simplicity of use, and ease of interpretation and by savings in technician time.  相似文献   
180.
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