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251.
Tropical Animal Health and Production - The aim of this study was to investigate the efficacy of dietary endotoxin binders [bentonite (BEN) and Saccharomyces cerevisiae cell wall (SCW)] on...  相似文献   
252.
Chikungunya virus (CHIKV) is a mosquito‐borne pathogen that causes CHIKV fever. Definitive diagnosis is crucial for patients experiencing symptoms similar to other arboviral diseases because they can vary in clinical consequences. An increasing number of patients experience long‐term rheumatic effects of CHIKV infection, but these cases may not be optimally detected by molecular assays and anti‐CHIKV IgM ELISAs (M‐ELISAs) used for confirmation and screening, respectively. The subsequent confirmatory serological test, the plaque reduction neutralization test (PRNT), is laborious and time‐consuming. In this study, we evaluated a new diagnostic algorithm in which the M‐ELISA is conducted in parallel with an anti‐CHIKV IgG ELISA (G‐ELISA) and observed that the Euroimmun M‐ELISA combined with the Euroimmun G‐ELISA or the Abcam G‐ELISA exhibited excellent sensitivity and specificity for CHIKV. The combinations demonstrated perfect and near perfect inter‐rater agreement with the PRNT, respectively, suggesting their potential to be used as alternatives to the confirmatory serological PRNT assay for CHIKV.  相似文献   
253.
OBJECTIVE: To characterize the effects of oral administration of a high dose of enrofloxacin to cats. ANIMALS: 24 (12 male and 12 female) young healthy cats. PROCEDURES: Cats were allocated on the basis of sex into 2 groups (4 males and 4 females/ group) from which 3 subgroups for 3 durations (3, 5, or 7 days) of enrofloxacin (50 mg/kg, PO, q 24 h) or control solution (1 mL of water, PO, q 24 h) administration that began on day -1 were created. Funduscopic examinations were performed daily. Electroretinography (ERG) was performed before and every 2 to 3 days after the start of oral administration. Four cats/study group were euthanized on days 3, 5, and 7, and eyes were collected for light and electron microscopic evaluations. RESULTS: Neurologic, funduscopic, and ERG abnormalities were evident only in cats administered enrofloxacin. Funduscopic changes (granular appearance or graying of the area centralis) were noticed on or before day 3 (after only 3 days of enrofloxacin administration), with subsequent similar changes along the visual streak. Vascular attenuation (between days 2 and 4) and generalized tapetal hyperreflectivity (between days 5 and 7) followed. Reduction in b-wave ERG amplitude preceded funduscopic changes. Morphologic changes in the photoreceptor layers correlated with duration of enrofloxacin administration, with generalized degenerative changes evident after 3 doses. CONCLUSIONS AND CLINICAL RELEVANCE: The study indicated that a high dose of enrofloxacin (50 mg/kg/d, PO) induced retinal and systemic changes. Enrofloxacin at 10 times the recommended dosage is acutely toxic to the outer retina of clinically normal cats.  相似文献   
254.
OBJECTIVE: To estimate disease prevalence among dogs and cats in the United States and Australia and proportions of dogs and cats that receive therapeutic diets or dietary supplements. DESIGN: Telephone survey. Sample Population-Dog and cat owners located in 5 geographic areas. PROCEDURES: A telephone survey was administered to dog and cat owners. RESULTS: Of 18,194 telephone calls that were made, 1,104 (6%) were to individuals who owned at least 1 dog or cat and agreed to participate. Information was collected for 635 dogs and 469 cats. Only 14 (1%) respondents indicated that their pet was unhealthy, but 176 (16%) indicated that their pets had 1 or more diseases. The most common diseases were musculo-skeletal, dental, and gastrointestinal tract or hepatic disease. Many owners (n = 356) reported their pets were overweight or obese, but only 3 reported obesity as a health problem in their pets. Owners of 28 (2.5%) animals reported that they were feeding a therapeutic diet, with the most common being diets for animals with renal disease (n = 5), reduced-calorie diets (5), and reduced-fat diets (4). Owners of 107 of 1,076 (9.9%) animals reported administering dietary supplements to their pets. Multivitamins (n = 53 animals), chondroprotective agents (22), and fatty acids (13) were the most common dietary supplements used. CONCLUSIONS AND CLINICAL RELEVANCE: Results suggest that most dogs and cats reported by their owners to have a health problem were not being fed a therapeutic diet. In addition, the rate of dietary supplement use was lower than that reported for people.  相似文献   
255.
256.
The aim of this project was to study the effects of feeding system (dry or wet feeding with whey), dietary lysine level and pre-slaughter routines on technological meat quality in entire male, female and castrated male pigs, which were carriers or non-carriers of the RN ? allele. The feeding system only affected the yield of processed meat, resulting in lower Napole yield (87.5% vs 89.4%) for meat of whey fed pigs. Further, lower dietary lysine levels resulted in higher drip loss of the meat compared with high dietary levels (5.3% vs 4.8%). Mixing of unfamiliar pigs prior to slaughter led to meat with lower internal reflectance values (28.3 vs 32.2) and glucose+G-6-P concentrations of the meat juice (46.3 vs 49.7 μmol/ml) compared with pen-wise slaughtering. In comparison with non-carriers, RN ? carriers had significantly lower ultimate pH, shear force values and water-holding capacity. Mixing of non-carrier pigs prior to slaughter gave higher Napole yield compared with those handled pen-wise. Females had lower ultimate pH and higher Napole yield compared with entire males.  相似文献   
257.
Summary In recent years, the rapid development of somatic cell genetics has made possible the transfer of alien genes over wide taxonomic distances by somatic hybridization. In this review, the potential of somatic hybridization in the breeding of crops within the Brassicaceae, Fabaceae, Poaceae and Solanaceae is discussed. It is evident from these studies that many hybrids, either symmetric or asymmetric, which are fertile have the potential to be used as a bridge between the alien species and the crop. Progeny analysis of some hybrid combinations also reveals intergenomic translocations which may lead to the introgression of the alien genes. Furthermore, fusion techniques enable the resynthesis of allopolyploid crops to increase their genetic variability and to restore ploidy level and heterozygosity after breeding at reduced ploidy level in polyploid crops.  相似文献   
258.
259.
Opsonization of yeast cells with equine iC3b, C3b, and IgG   总被引:1,自引:0,他引:1  
The main opsonins in serum are antibodies and complement factor C3. The opsonization mechanisms including complement activation and deposition are important in studies of phagocytosis and of mechanisms of microbial immune evasion. The objective of the present study was to monitor the deposition of complement C3 and IgG from equine serum on yeast cells (Saccharomyces cerevisiae) using a flow cytometric immunoassay. Correlations were made between the opsonic coating and phagocytic capacity using equine blood neutrophils. In addition, the bound C3 fragments were characterized by SDS–PAGE and Western blot analyses.

Opsonic coating of yeast with equine C3 and IgG occurred rapidly with detectable levels with as little as 0.75% serum. C3 deposition was a result of complement activation and no passive adsorption was observed. When complement was inactivated, the fluorescence indicating IgG deposition increased 3–6-fold, indicating spatial competition between C3 and IgG at binding.

Opsonization with 1.5% serum led to suboptimal equine neutrophil phagocytosis of yeast cells which was dependent on complement activation by the classical pathway. With ≥6.25% serum, IgG contributed to opsonization and phagocytosis. With 50% serum and more, C3 was deposited also by the alternative pathway. Phagocytosis rates became optimal with 3% serum, and did not increase further with higher serum concentrations. The main form of C3 on the yeast cells was iC3b and the rest was C3b without any detectable breakdown products (C3c or C3dg). The equine complement components are similar in size to the human equivalents.

It may be concluded that opsonization of yeast particles leading to phagocytosis, occurs at very low serum concentrations (1.5%) and that it is dependent on activation of the classical complement pathway at this low opsonic level. This is an important finding for efficient host defense, e.g. extravascular phagocytosis at infection sites.  相似文献   

260.
Acetylcholine synthesizing (ACh-s) activity, and binding of 3H--bungarotoxin (3H-Btx) and 3H-d-tubocurarine (3H-TC) were analysed in gluteus media muscle from normal cows and from cows suffering from parturient paresis, both at parturition and 3 months later. At parturition, the ACh-s activity was 50% lower in the muscle of paretic cows than in non-paretic cows. No difference was found in the number of 3H-Btx and 3H-TC binding sites at parturition, while 3 months after parturition the numbers of 3H-TC and 3H-Btx binding sites were significantly higher in normal than in paretic cows. These significant differences in the number of receptors and a possible underlying receptor regulation defect might be a plausible etiological factor for the disease parturient paresis.  相似文献   
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