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961.
Invasive woody plant expansion is a primary threat driving fragmentation and loss of sagebrush (Artemisia spp.) and prairie habitats across the central and western United States. Expansion of native woody plants, including conifer (primarily Juniperus spp.) and mesquite (Prosopis spp.), over the past century is primarily attributable to wildfire suppression, historic periods of intensive livestock grazing, and changes in climate. To guide successful conservation programs aimed at reducing top-down stressors, we mapped invasive woody plants at regional scales to evaluate landscape level impacts, target restoration actions, and monitor restoration outcomes. Our overarching goal was to produce seamless regional products across sociopolitical boundaries with resolution fine enough to depict the spatial extent and degree of woody plant invasion relevant to greater sage-grouse (Centrocercus urophasianus) and lesser prairie-chicken (Tympanuchus pallidicinctus) conservation efforts. We mapped tree canopy cover at 1-m spatial resolution across an 11-state region (508 265 km2). Greater than 90% of occupied lesser prairie-chicken habitat was largely treeless for conifers (< 1% canopy cover), whereas > 67% was treeless for mesquite. Conifers in the higher canopy cover classes (16 ? 50% and > 50% canopy cover) were scarce (< 2% and 1% canopy cover), as was mesquite (< 5% and 1% canopy cover). Occupied habitat by sage-grouse was more variable but also had a relatively large proportion of treeless areas (x? = 71, SE = 5%). Low to moderate levels of conifer cover (1 ? 20%) were fewer (x? = 23, SE = 5%) as were areas in the highest cover class (> 50%; x? = 6, SE = 2%). Mapping indicated that a high proportion of invading woody plants are at a low to intermediate level. Canopy cover maps for conifer and mesquite resulting from this study provide the first and most geographically complete, high-resolution assessment of woody plant cover as a top-down threat to western sage-steppe and prairie ecosystems.  相似文献   
962.
963.
A 1‐year‐old, previously spayed phenotypic female Poodle/Soft‐coated Wheaten Terrier (Whoodle) cross was presented for a suspected ovarian remnant. Serum luteinizing hormone (LH) concentration was below the detection limit (<1 ng/ml Witness® LH), and serum progesterone concentration was elevated in the chemiluminescence immunoassay (CLIA; 20 ng/ml), consistent with dioestrus and presence of ovarian tissue. Transabdominal ultrasound revealed a retroperitoneal soft tissue structure suspected to be a gonad. On exploratory laparotomy, a gonad was removed from the cranial retroperitoneum, cranial to the right kidney, after ligation of its primary blood supply. Histological examination proved the gonad to be an ovotestis. Subsequent cytogenetics revealed a 78 XX karyotype, thus confirming the diagnosis of ectopic ovotestis in a XX ovotesticular, SRY‐negative, disorder of sexual development in a dog.  相似文献   
964.
Bovine herpesvirus 4 (BoHV-4) has been isolated from cattle throughout the world. Interestingly, a survey of wild African buffaloes mainly from the Maasai Mara Game Reserve in Kenya revealed that 94% of the animals tested had anti-BoHV-4 antibodies [Rossiter, P.B., Gumm, I.D., Stagg, D.A., Conrad, P.A., Mukolwe, S., Davies, F.G., White, H., 1989. Isolation of bovine herpesvirus-3 from African buffaloes (Syncerus caffer). Res. Vet. Sci. 46, 337–343]. These authors also proposed that the serological antigenic relationship existing between BoHV-4 and alcelaphine herpesvirus 1 (AlHV-1) could confer to BoHV-4 infected buffaloes a protective immune response against lethal AlHV-1 infection. In the present study, we addressed two questions related to Rossiter et al. paper. Firstly, to investigate the role of the African buffalo as a natural host species of BoHV-4, the seroprevalence of anti-BoHV-4 antibodies was analysed in wild African buffaloes throughout eastern and southern Africa. A total of 400 sera was analysed using two complementary immunofluorescent assays. These analyses revealed that independently of their geographical origin, wild African buffaloes exhibit a seroprevalence of anti-BoHV-4 antibodies higher than 68%. This result is by far above the seroprevalence generally observed in cattle. Our data are discussed in the light of our recent phylogenetic study demonstrating that the BoHV-4 Bo17 gene has been acquired from a recent ancestor of the African buffalo. Secondly, we investigated the humoral antigenic relationship existing between BoHV-4 and AlHV-1. Our results demonstrate that among the antigens expressed in AlHV-1 infected cells, epitope(s) recognised by anti-BoHV-4 antibodies are exclusively nuclear, suggesting that the putative property of BoHV-4 to confer an immune protection against AlHV-1 relies on a cellular rather than on a humoral immune response.  相似文献   
965.
An experimental neuroanatomic investigation of the innervation of the dog's tongue by the method of retrograde axonal transport of horseradish peroxidase required that chorda tympani neurectomy be performed in neonatal pups. Surgical exposure and transection of the chorda tympani proximal to its union with the lingual branch of the mandibular nerve in the past has been accomplished by radical lateral approach which is suited only for acute experimentation. This report describes a ventral surgical exposure of the extracranial portion of the chorda tympani in the dog. This surgical procedure permits long-term survival and is considered especially useful for the chronic neuroanatomic and neurophysiologic investigations on the role of the chorda tympany in taste, salivation and lingual vasodilation in the dog.  相似文献   
966.
967.
A primary culture system of equine uterine epithelial cells was developed to study interactions between these cells in vitro. Cultures were prepared by combined mechanical and collagenase separation of cells from endometrial biopsies taken from mares during estrus and diestrus. Cells were maintained in DME/F12 medium containing 10% fetal bovine serum. The purity of the epithelial cell population was estimated to be greater than 95% based upon the cobblestone morphology of cells and a uniform indirect immunofluorescence labelling of cells with an antibody directed against cytokeratin intermediate filament proteins. Radiating cytoplasmic cytokeratin filaments were characteristic of cells labelled after 3 days in culture. Preliminary analysis of the incidence and rate of cell-to-cell communication between epithelial cell populations was conducted using a fluorescence recovery after photobleaching assay. Recovery of carboxyfluorescein fluorescence in cells which were laser photobleached and in contact with other cells was monitored at one-minute intervals over 5 minutes. The incidence of communication among cells isolated during estrus and diestrus was 100%. The mean rates of fluorescence recovery at one minute (8.25% ± SEM 0.91 and 10.94% ± SEM 1.20 for cells obtained from estrous and diestrous mares, respectively) were not significantly different. These studies indicate that cells isolated from the endometrium of the mare are capable of intercellular diffusion of regulatory and informational molecules between cells in contact.  相似文献   
968.
The effect of using Propionibacterium acnes, (EqStim®)a as an adjunct to conventional therapy in the treatment horses with Equine Respiratory Disease Complex (ERDC) was evaluated. Of the 45 horses entering the study, 25 received EqStim® and conventional therapy while 20 horses (negative controls) received a carrier solution of 12.5% ethanol-saline and conventional therapy. At the end of the 14 day test period, 96% (24/25) of the horses treated with EqStim® and conventional therapy showed clinical improvement or complete recovery as compared to the control group in which 35% (7/20) of the horses (treated with conventional therapy and carrier) showed clinical improvement or complete recovery.  相似文献   
969.
Neuroaxonal dystrophy in a rottweiler pup   总被引:1,自引:0,他引:1  
An 8-month-old Rottweiler pup was evaluated for neurologic disorder. Clinical signs included ataxia, hypermetria of all 4 limbs, intention tremors of the head, lack of a menace reflex bilaterally, and mild proprioceptive deficits. The pup was euthanatized because of the progressive nature of the disease. Histopathologic findings consisted of decreased numbers of Purkinje cells in the cerebellum and moderate numbers of axonal spheroids in the nucleus cuneatus. This latter finding confirmed the diagnosis of neuroaxonal dystrophy.  相似文献   
970.
A 10-month-old Friesian filly had a presentation that was consistent with chronic left- and right-sided congestive heart failure. Clinical pathology findings included abnormal haematological and biochemical variables, abnormal blood gas values and increased serum concentration of cardiac troponin I. Echocardiography revealed cardiac chamber dilation and dextropositioning of the aorta. Radiography revealed a generally enlarged heart and pulmonary interstitial infiltration. These findings were supported at necropsy and the diagnosis of double-outlet right ventricle was confirmed. The pathological changes and physiological responses subsequent to double-outlet right ventricle have not previously been described in detail in horses. Clinical progression closely resembles that seen in humans, in whom antemortem diagnosis relies on echocardiography. In horses, complex cardiac disease presents a diagnostic challenge to the clinician. Appropriate therapy must be based on an accurate diagnosis.  相似文献   
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