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31.
32.
A new class of compounds, derived from hydroquinones, has been synthesised and bioassayed for juvenile hormone activity on yellow mealworm (Tenebrio molitor), confused flour beetle (Tribolium confusum), and mediterranean flour moth (Anagasta kuehniella). Structure-biological activity relationships of the most significant products are tabulated and discussed. Two of the new compounds, 1, 4-bis(5-chloropent-4-ynyloxy) benzene (I) and 1-(5-chloropent-4-ynyloxy)-4-phenoxybenzene (II), showed outstanding activity in morphogenetic assay with T. molitor, and good field persistence. Product II is of particular interest for the control of various Homopteran species, mosquitoes, stored product pests and fire ants.  相似文献   
33.
In the search for new juvenile hormone analogues (JHAs), a general approach was chosen based on the substitution of the isoprene unit, that carries the epoxy function in the natural hormone JHIII, by 3,3,3-trichloropropyl, 2,2-dichlorocyclopropyl- methyl, 3,3-dichloroallyl, or 3-chloroprop-2-ynyl groups. Accordingly, several terpenoid aromatic JHAs were prepared with, or without, oxygen atoms in the aliphatic chain. Structure-biological activity relationships of the most active compounds toward the yellow mealworm (Tenebrio molitor) and the large cabbage white butterfly (Pieris brassicae) are given. With a view to preparing synthetically accessible analogues, some alkyl phenyl ethers were also made, which were not branched in the aliphatic chain and were related terminally to the most active compounds. They were only moderately active against insects when tested for morphogenetic activity, but exhibited a good field persistence. The occurrence of a moderate acaricidal activity among these analogues prompted the examination of several 1,4-disubstituted-phenyl derivatives. The ovicidal effectiveness of these products against a susceptible strain of the two-spotted spider mite, Tetranychus urticae, was ten or 100 times higher than that of the well known and highly potent JHAs.  相似文献   
34.
The recent advances in the nutrition of companion animals has resulted in a longer possible life-span for dogs and cats and an improvement in their quality of life. Numerous studies about geriatric animals show that an aging dog or cat requires a specific nutritional formulation that considers the metabolic changes associated with age. A correct diet plays an important role in the treatment of some chronic pathologies in aging animals, particularly those for which the aging process modifies the organ function. A correct diet can provide therapeutic support to the administration of drugs that can sometimes compromise organ function. In the present study, we identify key aspects of the clinical nutrition during chronic renal disorders of dogs and cats, diseases with an elevated incidence and a major cause of mortality in geriatric animals. The aim of nutritional treatment for dogs and cats affected by chronic renal disorders is to improve the quality and length of life, assuring an adequate amount of energy and slowing the progression of renal failure. To improve treatment efficacy it is necessary to prepare different dietary rations during the various stages of disease, on the basis of clinical signs and laboratory data.  相似文献   
35.
BACKGROUND: Osteogenic sarcomas are rare in rabbits, but cases involving the mandible, ribs, frontal bones, and tibia have been reported. OBJECTIVE: The purpose of this study was to describe the clinical and pathologic findings in a rabbit with osteosarcoma and multiple metastases with subcutaneous involvement. METHODS: A 1-year-old female Polish rabbit was evaluated for dysorexia, lameness, gait difficulties with the hind limbs, and the presence of 2 subcutaneous nodules, on the left thigh and in the dorsal region. A hard swelling was also present at the base of the tail. Radiographic findings revealed multiple abnormalities in several bones, which were more severe in the sacrococcygeal region and femur. Several areas of calcification involving the thorax and abdomen as well as skeletal muscles, also were noted. The thigh nodule was surgically removed, and cytologic and histologic evaluations were performed. Following the rabbit's death, postmortem radiographs were taken and necropsy was performed. Samples of tissues and organs, involved bone segments, and other subcutaneous nodules were collected and examined by cytology and histology. RESULTS: Both the subcutaneous nodules and the majority of tissues and organs contained neoplastic cells whose appearance was consistent with osteogenic sarcoma. CONCLUSION: Clinical, radiologic, and pathologic data supported a diagnosis of osteosarcoma with multiple metastases and subcutaneous involvement.  相似文献   
36.
An outbreak of giardiasis was observed in a sheep farm in Central Italy. Infected lambs (30-90 days of age) showed a malabsorption syndrome, decreased weight gain and impairment in feed efficiency. The most relevant clinical sign was the excretion of malodorous and poorly formed faeces, whereas diarrhoea was rarely observed in the flock. Laboratory investigations revealed the presence of Giardia in affected animals, while no other significant viral, bacterial or parasitic pathogens were identified in faeces or tissue samples. A mild to severe infiltrative enteritis with eosinophils, lymphocytes and plasma cells was detected in histological sections of the gut. Giardia parasites collected from duodenal aspirates were typed as Giardia duodenalis Assemblage B, by PCR amplification and sequencing of the TPI gene. Treatment with fenbendazole at a dose of 10mg/kg for 3 consecutive days, successfully cleared the infection. These results show that G. duodenalis can cause significant economic losses in sheep farming.  相似文献   
37.
This study was designed to evaluate whether the outcome of artificial insemination (AI) was affected by the metabolic and oxidative status of dairy cows. Seventy-nine inseminations in 40 cows, were classified, on the basis of blood progesterone (P4) and pregnancy-associated glycoprotein (PAG) concentrations and clinical confirmation of pregnancy into, three categories: (1) positive (AI+, resulted in pregnancy, n=26; 33%), (2) negative (AI-, did not result in pregnancy, n=49; 62%), and (3) embryonic mortality (EM, n=4; 5%). Reactive oxygen metabolites, biological antioxidant potential, oxidative stress index, body condition score, glucose, total proteins, albumin, urea, non-esterified fatty acids (NEFAs), cholesterol, triglycerides, haptoglobin and advanced oxidative protein products (AOPPs) were measured on the day of AI (day 0), and 30 and 42days later. Cows with EM had lower BCS scores (2.5) than AI+ (2.8) and AI- (2.9) cows (P<0.05). During the post-partum period, body condition score (BCS) increased and NEFAs decreased (P<0.05) suggesting a recovery from the negative energy balance (NEB). The only significant differences found were that the mean concentration of AOPPs was higher and that of albumin lower in EM cows than in AI+ and AI- (P<0.05) animals. Plasma concentration of reactive oxygen metabolites and biological antioxidant potential were not related to AI outcome. Further studies are required to confirm this finding and to clarify the role of oxidative status on cows' fertility.  相似文献   
38.
Cortisol may be useful as a marker in predicting how an animal will respond to stressful stimuli, thus providing information on animal's temperament. To quantify the level of transport stress and the effect of temperament on the adrenocortical response, the change in circulating cortisol levels was evaluated in 84 healthy experienced thoroughbred and crossbred stallions, mean age 11.4 ± 4.5 years old, after road transport in a commercial trailer (6 horses per load, stocking density: 2 m2/horse), over mean distances of 210 ± 11.8 km for about 3 hours. Several experienced caretakers were asked to complete 2 questionnaires, one that used a 5-point scale to subjectively evaluate temperament and another that used a 3-point scale to assess tendencies in response to ordinary care and daily management. The scores for the latter were defined as follows: a score of 1 indicated that the horse had never or rarely troubled the caretaker during management, 2 occasionally, and 3 usually. On this basis, the subjects were distinguished between calm and nervous stallions. Blood samples were taken same daytime (8.00 am), in single box, immediately before loading, then after transport and unloading. Serum cortisol concentrations were analyzed in duplicate by immunoenzymatic assay. Compared with basal levels, cortisol increases were observed in both calm (P < 0.001) and nervous (P < 0.05) stallions after transport. Repeated-measures analysis of variance showed significant effects of transport on cortisol changes (P < 0.001). Nervous subjects showed lower (P < 0.01) cortisol levels than did calm subjects after transport, and basal cortisol levels did not differ between calm and nervous subjects. No significant differences (P > 0.05) between different age, breed, and orientation were detected.The results showed that temperament could influence the adrenocortical responses of stallions after short-term transportation. The presence of the same staff for handling, loading, confinement, and unloading, the same veterinarian taking all blood samples, and the presence of cospecifics did not reduce the response to short transport stress both in calm and nervous stallions already accustomed to transport. Lower cortisol concentrations in nervous subjects might be because of failure of the adrenal cortex to respond normally to transport stress. Moreover, signs of transport stress were less pronounced in nervous stallions.  相似文献   
39.
A case of pulmonary carcinoma in a 23-year-old Quarterhorse mare is described. On physical examination, depression, poor body condition, tachypnea, bilateral serosanguineous nasal discharge and a wide area of reduced breath sounds in association with the right hemithorax were detected. Laboratory evaluation showed leukocytosis with neutrophilia and lymphopenia, hyperfibrinogenemia, hyperprotidemia, hypoalbuminemia, increased beta 2 and gamma globulin fractions, hypoxemia, and normocapnia. Radiography and thoracic ultrasonography revealed a large rounded mass extending from the 9th to the 14th right intercostal space, where neither bronchial nor vascular structures were detectable. Endoscopy showed a large amount of serosanguineous fluid within the tracheal lumen and a mass of reddish soft tissue completely obliterating the right caudal lobar bronchus. Histopathology of the endobronchial mass and of the transthoracic ultrasound-guided biopsy samples was consistent with a primary pulmonary epithelial tumor. Due to worsening of the clinical condition, the mare was euthanized. Postmortem examination confirmed the presence of a large 30-cm mass located in the right caudal pulmonary lobe, characterized by epithelial cells arranged in papillary projections and alveolar structures, findings consistent with bronchioloalveolar carcinoma.  相似文献   
40.
Follicle-stimulating hormone has been widely used to induce superovulation in buffaloes and cows and usually triggers functional and morphologic alterations in the corpus luteum (CL). Several studies have shown that FSH is involved in regulating vascular development and that adequate angiogenesis is essential for normal luteal development. Angiogenesis is regulated by many growth factors, of which vascular endothelial growth factor (VEGF) and fibroblast growth factor 2 (FGF2) have an established central role. Therefore, we have used a combination of in vitro and in vivo studies to assess the effects of FSH on the expression of VEGF and FGF2 and their receptors in buffalo luteal cells. The in vivo model consisted of 12 buffalo cows, divided into control (n = 6) and superovulated (n = 6) groups, and CL samples were collected on day 6 after ovulation. In this model, we analyzed the gene and protein expression of FGF2 and its receptors and the protein expression of VEGFA systems with the use of real-time PCR, Western blot analysis, and immunohistochemistry. In the in vitro model, granulosa cells were collected from small follicles (diameter, 4–6 mm) of buffaloes and cultured for 4 d in serum-free medium with or without FSH (10 ng/mL). To induce in vitro luteinization, LH (250 ng/mL) and fetal bovine serum (10%) were added to the medium, and granulosa cells were maintained in culture for 4 d more. The progesterone concentration in the medium was measured at days 4, 5, and 8 after the beginning of cell culture. Cells were collected at day 8 and subjected to real-time PCR, Western blot analysis, and immunofluorescence for assessment of the expression of FGF2, VEGF, and their receptors. To address the percentage of steroidogenic and growth factor-expressing cells in the culture, flow cytometry was performed. We observed that in superovulated buffalo CL, the FGF2 system mRNA expression was decreased even as protein expression was increased and that the VEGF protein was increased (P < 0.05). In vitro experiments with granulosa cells showed an increase in the mRNA expression of VEGF and FGF2 and its receptors 1 and 2 and protein expression of VEGF, kinase insert domain receptor, FGF receptor 2, and FGF receptor 3 in cells treated with FSH (P < 0.05), in contrast to the in vivo experiments. Moreover, the progesterone production by FSH-treated cells was elevated compared with untreated cells (P < 0.05). Our findings indicate that VEGF, FGF2, and their receptors were differentially regulated by FSH in vitro and in vivo in buffalo luteal cells, which points toward a role of CL environment in modulating cellular answers to gonadotropins.  相似文献   
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