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71.
Mendes LC Peiró JR Feitosa FL Luvizotto MC Borges AS Ciarlini PC Perri SH 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》2005,19(6):899-904
The goals of this study were to evaluate techniques for collection of peritoneal fluid from calves, establish reference ranges for fibrinogen in peritoneal fluid during the 1st month of life, and determine if abomasal puncture would alter peritoneal fluid or hematologic variables. Twenty-two healthy Holstein calves underwent 3 peritoneal fluid collections on day 1, day 15, and day 30 of age. Fibrinogen concentration in peritoneal fluid was 0.20 g/dL and 0.10 g/dL (P < .05) for day 1 and day 30, respectively, and 0.10 at day 15 (P > .05) for calves without abomasal puncture. Plasma fibrinogen concentration was 0.60 g/dL and 0.70 g/ dL (P < .05) for days 15 and 30, respectively, in calves without abomasal puncture. There were no significant differences (P < or = .05) in peritoneal fluid and peripheral blood total protein and fibrinogen concentrations, specific gravity, total and differential cell count, or erythrocyte counts between calves with or without abomasal puncture. We concluded that the reference ranges established for fibrinogen and total protein concentration are important for accurate evaluation of peritoneal fluid in calves for further comparison with similar-aged animals with gastrointestinal-tract or abdominal-cavity disease. Additionally, accidental abomasal puncture does not alter values of fibrinogen, total protein, and nucleated cell count in peritoneal fluid and does not cause apparent clinical abnormalities. 相似文献
72.
Holgersson J Ehrnfelt C Hauzenberger E Serrander L 《Veterinary immunology and immunopathology》2002,87(3-4):407-415
In cases where antibody- and complement-mediated hyperacute rejection (HAR) of vascularized organ xenografts has been prevented, acute vascular rejection (AVR) and acute T cell-mediated rejection (ACR) cause graft destruction. Infiltration of leukocytes (innate and graft-primed T cells) into the graft execute the latter two rejection modalities. The leukocyte extravasation process, which is a prerequisite for graft infiltration, is governed by adhesion molecules, including the selectin, integrin and immunoglobulin protein families, and the chemokine protein family. The compatibility between porcine endothelial cell and human leukocyte adhesion molecules was investigated in dynamic adhesion and static transendothelial migration assays. The effect of human anti-pig antibodies on human leukocyte adhesion to, and transendothelial migration across, porcine endothelium was assessed under dynamic and static conditions, respectively. In contrast to previously published results, no difference in the ability of neutrophils to adhere to pig and human endothelium was observed. Furthermore, no evident quantitative or qualitative differences in the capacity of human and porcine endothelium to support transendothelial migration of human leukocytes (T, B and natural killer (NK) cells, monocytes, and neutrophils) could be detected. The presence of human anti-pig antibodies (Abs) modulated the migration of leukocytes across porcine endothelium, as well as neutrophil adhesion to porcine endothelium under conditions of flow. Antibodies specific for pig endothelial adhesion molecules can potentially be used as species (graft)-specific immunosuppressive reagents in order to prevent cellular organ xenograft rejection. 相似文献
73.
Moore DP Campero CM Odeón AC Posso MA Cano D Leunda MR Basso W Venturini MC Späth E 《Veterinary parasitology》2002,107(4):303-316
The purpose of the present work was to study the epidemiology of Neospora caninum in beef and dairy herds in the Humid Pampas of Argentina. The seroprevalence of N. caninum was evaluated in 2414 serum samples of cows from beef and dairy farms. An indirect fluorescent antibody test (IFAT) was used to determine specific antibodies. The sera was screened at a dilution >or=1:200 and >or=1:600 in cows with reproductive disease antecedents and without them, respectively. Cows without history of reproductive diseases from nine beef and fifteen dairy farms were grouped according to the percentage (> or or 相似文献
74.
The mammalian intestine harbors complex societies of beneficial bacteria that are maintained in the lumen with minimal penetration of mucosal surfaces. Microbial colonization of germ-free mice triggers epithelial expression of RegIIIgamma, a secreted C-type lectin. RegIIIgamma binds intestinal bacteria but lacks the complement recruitment domains present in other microbe-binding mammalian C-type lectins. We show that RegIIIgamma and its human counterpart, HIP/PAP, are directly antimicrobial proteins that bind their bacterial targets via interactions with peptidoglycan carbohydrate. We propose that these proteins represent an evolutionarily primitive form of lectin-mediated innate immunity, and that they reveal intestinal strategies for maintaining symbiotic host-microbial relationships. 相似文献
75.
Efficacy of Hypovirulent Binucleate Rhizoctonia sp. to Control Banded Leaf and Sheath Blight in Corn
Cecilia B PASCUAL Avelino D RAYMUNDO Mitsuro HYAKUMACHI 《Journal of General Plant Pathology》2000,66(1):95-102
Water agar, artificially infested soil and leaf sheath inoculation methods were used to assess the suitable time of application,
varietal host response and persistence of Rhv7, a hypovirulent, binucleate Rhizoctonia collected from soil in the Philippines, to effectively control virulent Rhizoctonia solani AG1-IA isolate RS35 on corn. With the water agar method, prior inoculation (2 to 3 days) with the biocontrol agent is essential
to achieve maximum control of the pathogen. Disease protection was increased from 23 to 70% as the pre-incubation time of
Rhv7 prior to the challenge inoculation with virulent isolate was lengthened from 0 to 3 days. Disease severity and incidence
of banded leaf and sheath blight (BLSB) on the three corn hybrids were also suppressed in artificially infested soil. In leaf
sheath inoculation, the suppressive ability of Rhv7 against BLSB on corn persisted during lesion expansion. This suppression
was expressed as slower disease progress in plants with Rhv7 than in plants without Rhv7. Early and timely brace root formation
that detached infected sheaths, also aided in reducing the number of diseased plants in Rhv7-treated plots at the final observation.
Mycelial growth activity of RS35 was reduced when corn plants were pre-inoculated with Rhv7 before challenge even if there
was no contact detected between Rhv7 and RS35, which suggests that Rhv7 protects corn against BLSB by induced resistance.
The hypovirulent, binucleate Rhizoctonia Rhv7 strain effectively controlled R. solani AG1-IA isolate RS-35 in corn.
Received 30 August 1990/ Accepted in revised form 25 October 1999 相似文献
76.
Jose Alfredo Gutierrez-Reyes ;Estela Flores-Velazquez ;Guillermo Agustin Reyes-Escalona ;Joaquin BraulioDelgadillo-Alvarez ;Marcela Amalia Mercado-Pezzat ;Eli Tonatiuh Selva-Hernandez ;Alejandro Perera-Ortiz ;Jose Alberto Ordufia-Sumaran ;Cecilia Romero-Torres ;Luis Antonio Jimenez-Zamudio ;Ethel AwildaGarcfa-Latorre Citlatepetl Salinas-Lara 《农业科学与技术》2014,(4):277-290
Mexico is considered by different international organizations as a country where the bovine tuberculosis is an endemic problem. However, there are important and consistent improvements in eradicating the disease by the implementation of government policies and with the livestock organization support. The current situation of the program shows good results regarding decreasing the prevalence, and as a consequence, the risk of this disease for public health and animal health, as well as the improvement in animal production and international and national trade. Today, the bovine tuberculosis distribution is almost known in Mexico. In addition, a series of controls and indicators have been established, which allow maintain consistency and reliability in the data that are managed and analyzed. 相似文献
77.
Background
Congenital tremor is associated with demyelination of the brain and spinal cord and is clinically noted as outbreaks of trembling and shaking in newborn piglets during a limited time-period. Six forms of the disease have been described, where form AII may be caused by an, as yet, unidentified viral infection. This study aimed to investigate the presence of astrovirus and circovirus by sequencing and polymerase chain reaction (PCR) analysis and by relating the findings to the occurrence of disease and lesions in the brain, in 4–6 days-old piglets obtained from a clinical outbreak of congenital tremor.Results
In piglets with congenital tremor, there were mild to moderate vacuolar changes of the white matter in the cerebrum, brain stem and cerebellum. In healthy piglets, less conspicuous vacuolar changes were detected. One healthy and one diseased piglet were positive for porcine circovirus type 2. The nested pan-PCR showed the presence of astrovirus in at least one brain region in all piglets and by sequencing, two different porcine astrovirus lineages were identified.Conclusions
The results do not support previous studies identifying porcine circovirus type 2 as the cause of congenital tremor. The demonstration of astrovirus in the brain of piglets suffering from congenital tremor is interesting. However, astrovirus was demonstrated in both healthy and diseased individuals and therefore, further studies are warranted to determine the possible involvement of astrovirus in the pathogenesis of congenital tremor in pigs. 相似文献78.
79.
Walter Basso Gastón Moré Maria Alejandra Quiroga Diego Balducchi Gereon Schares Maria Cecilia Venturini 《Veterinary parasitology》2014,199(3-4):255-258
Neospora caninum is a worldwide distributed protozoan that may cause neuromuscular disease in dogs and reproductive failure in domestic and wild ruminants. One axis fawn (Axis axis) and four neonates from the same deer herd died at a zoo in Argentina within a four-month period. The fawn presented with dilatation of the anal sphincter at birth and incontinence, developed weakness and ataxia and died at 14 days of age. At necropsy, a mega formation of the distal large intestine was observed. Microscopically, non-suppurative encephalitis, suppurative bronchopneumonia, fibrin necrotic enteritis and degenerative changes in the liver were observed in hematoxilin and eosin-stained tissue sections, and thick-walled N. caninum-like cysts were observed in fresh brain samples. Serologic studies for N. caninum revealed an IFAT titer of 1:6400 in the fawn and 1:25, 1:400, 1:3200 and 1:6400 in the neonates. N. caninum DNA was detected in brain samples from the fawn and from one neonate by PCR, and the parasite was isolated in vitro from the fawn’ brain after passage through gerbils (Meriones unguiculatus) and gamma-interferon knock-out mice. N. caninum DNA obtained from the fawn, neonate and isolated parasites showed the same microsatellite pattern. This suggests a common infection source for both animals.The diagnosis of N. caninum infection was confirmed, suggesting its association with perinatal mortality in captive axis deer. To the best of our knowledge, this is the first report of clinical disease associated to N. caninum infection in axis deer and of isolation of the parasite from this wild ruminant species. 相似文献
80.