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101.
A 3‐year‐old Paint gelding was presented for sudden onset of cataract affecting the right eye. Ophthalmic examination revealed subtle to mild microphthalmia and a mature cataract affecting the right globe. The right eye was treated with an antibiotic‐corticosteroid ophthalmic ointment and phacofragmentation was recommended. On re‐examination 5 months later, resorption of the cortex of the right lens and a morgagnian cataract were evident. The nucleus was positioned ventronasally in the lens capsule. The right eye had light perception, and a menace response was present. Examination of the right fundus via binocular indirect ophthalmoscopy was not possible. Ophthalmic ultrasonography revealed that the right globe was 4 mm shorter in axial length when compared with the left globe. There was a marked reduction in the size of the right lens vs. the left lens, and the presence of a moderate amount of hyperechoic debris was identified within the vitreal compartment of the right globe. Phacofragmentation, irrigation and aspiration of the morgagnian cataract and an anterior vitrectomy were performed. On postoperative examination, the eye was comfortable and a menace response was present. The horse regained useful vision and continues to have a comfortable, visual eye 7 months postoperatively.  相似文献   
102.
The relationship of cataract maturity to intraocular pressure in dogs   总被引:2,自引:2,他引:0  
Objective To determine the distribution of intraocular pressure, as measured by applanation tonometry, in dogs with cataracts, and compare these tonometric results to the different stages of cataract formation (incipient, immature, mature, and hypermature). Animals studied Retrospection study of canine clinical patients (86 dogs). Procedures All records of dogs presented from 1991 to 1996 to the university veterinary medical teaching hospital for diagnosis of cataracts and evaluation for cataract surgery were reviewed. The tonometric measurements from the initial ophthalmic examination were selected in cataractous and nonglaucomatous eyes either receiving no topical or no systemic medications. The stage of cataracts was based on the degree of opacification, tapetal reflection, clinical vision, and visibility of the ocular fundus by indirect ophthalmoscopy. The distribution of tonometric results were grouped by the cataract maturity, and compared by anova and Tukey’s general linear tests. Results Intraocular pressure with incipient cataracts ranged from 9 to 17 mmHg (mean 12.7 ± 1.2 mmHg). Intraocular pressure with immature cataracts ranged from 3 to 27 mmHg (mean 13.6 ± 0.6 mmHg). For the mature cataracts, IOP ranged from 5 to 22 mmHg (mean 11.9 ± 0.7 mmHg). For the hypermature cataract group, IOP ranged from 4 to 23 mmHg (mean 10.8 ± 0.6 mmHg). Comparison of the tonometric results among the different stages of cataract formation indicated a significant difference (P = 0.0086) between only the immature and hypermature groups. Conclusions Intraocular pressure in lens‐induced uveitis (LIU) is lowered but the relationship to the stage of cataract maturity is less clear. Significant tonometric differences were present between the immature and hypermature cataract groups, but these differences are too small to be clinically useful. Decreased intraocular pressure of dogs with all stages of cataract formation suggests concurrent LIU during all stages of cataract formation, especially with the mature and hypermature stages. The average tonometric measurements in dogs with these cataracts were about two standard deviations below the mean IOP reported in normal dogs.  相似文献   
103.
The objective of this study was to describe the clinical, histologic and immunohistochemical features, the surgical treatment, and outcome of a cataract secondary to persistent hyperplastic tunica vasculosa lentis/persistent hyperplastic primary vitreous (PHTVL/PHPV) in a dog. A 4-month-old male Bloodhound dog presented for evaluation of a cataract. A complete ophthalmic examination and ocular ultrasonography were performed. A resorbing cataract with intralenticular hemorrhage, lens induced uveitis, and PHTVL/PHPV were diagnosed. Extracapsular cataract extraction using phacoemulsification was performed. A primary posterior capsulectomy was performed to remove a retrolental plaque with the posterior capsule; the excised plaque was submitted for histopathology and immunohistochemical staining. A 41-Diopter intraocular lens (IOL) was implanted. Functional vision was maintained postoperatively during the 21-month follow-up period. Histologically, the posterior capsule was coiled and exhibited duplication. The retrolental plaque was comprised of dense fibrous connective tissue, blood vessels, free red blood cells, hemosiderin-laden macrophages, a pocket of neural tissue and numerous perivascular mast cells. With immunohistochemical staining, the neural elements were determined to be glial cells compatible with astrocytes. Cataract secondary to PHTVL/PHPV can be successfully treated using phacoemulsification and planned posterior capsulectomy. Posterior lens capsule duplication, mast cells and astrocytic glial cells may be normal components of the fibrovascular retrolental plaque associated with PHTVL/PHPV.  相似文献   
104.
Secondary glaucomas in the dog in North America   总被引:1,自引:1,他引:0  
OBJECTIVE: To determine the prevalence of secondary glaucomas in dogs associated with cataract formation, lens luxation or displacement, cataract surgery, uveitis, hyphema and intraocular neoplasia. METHODS: Information was obtained from the Veterinary Medical Data Base (VMDB) from all veterinary medical teaching hospitals in North America from March 1964 to March 2003. Secondary glaucomas were diagnosed at the same examination or after the primary diagnosis was made, and included those associated with cataract formation, lens luxation, cataract surgery, uveitis of unknown cause, hyphema of unknown cause, and intraocular neoplasia. The data were evaluated by decade, breed, gender and age of presentation. RESULTS: A total of 1 592 831 dogs were presented, and 9695 canine secondary glaucomas. Secondary glaucoma associated with cataract formation represented 81% of all the canine secondary glaucomas. Breeds (n = 7890 dogs) predisposed to secondary glaucoma and cataracts had an overall prevalence of 0.5%, but nearly 20% of all the cataractous dogs developed secondary glaucoma in at least one eye. For the years 1994-2003, these breeds included the American Cocker Spaniel; Boston Terrier; Toy, Miniature and Standard Poodle; English Springer Spaniel; Bichon Frise; and Labrador Retriever. The other forms of secondary glaucoma occurred less frequently, and included those glaucomas with lens luxation or displacement (779 dogs; 12.0%), postcataract surgery (528 dogs; 5.1%), with uveitis from unknown cause (399 dogs; 7.1%), with hyphema from unknown cause (117 dogs; 7.3%), and with intraocular neoplasia (19 dogs; 3.5%). The risk of the secondary glaucomas from 1984 to 2002 was highest after the intracapsular lens extraction (ICLE), less in the extracapsular technique (ECLE), and lowest for the phacoemulsification/phacofragmentation method. CONCLUSION: Prevalence of the canine secondary glaucomas ranges from 0.25% (1964-1973), 0.46% (1974-1983), 0.79% (1984-1993), to 0.80% (1994-2003) and are as frequent as the primary or breed-related glaucomas during these same time periods.  相似文献   
105.
 Differently managed oxisols from Central Brazil were studied using a sequential P fractionation procedure because the effects of land use on the distribution of P forms in these soils are barely known. Therefore levels of labile and recalcitrant P forms in the natural Cerrado savanna were compared with those of crop, pasture and reforestation sites on differently textured oxisols. Under natural conditions of strong P deficiency, >60% of labile P was organic P (Po), reflecting the high contribution of Po to plant nutrition. Fertilisation after land-use change only increased levels of inorganic P (Pi) forms, the increase being most accentuated in the labile Pi fraction. At the crop and the pasture sites P tended to accumulate as recalcitrant P forms in the clayey soils, while in the loamy soils there was only a minor enrichment, probably due to the lower amounts of Fe- and Al-(hydr)oxides. In the reforestation sites, labile P was maintained at high levels, most likely through efficient recycling of the litter. The P fractionation procedure was also applied to particle-size fractions which reflected P transformations along an organic and mineralogical gradient. The clay fraction corresponded to 69–87% of total P and appeared to be both a sink for highly recalcitrant P and a source for labile P, especially labile Po. The sequential P fractionation procedure was also an effective method with which to detect the presence of fertiliser-P residues in the coarse-silt fraction. Received: 18 June 1999  相似文献   
106.
4个水稻高产品种与巴西陆稻的耐旱性比较研究   总被引:5,自引:1,他引:4  
徐孟亮  陈良碧 《作物学报》2003,29(6):903-907
在营养生长期与生殖生长期分别进行自然干旱与人工气候干旱处理,比较研究了4个水稻高产品种(组合)V989、汕优198、培两优特青及两优681与巴西陆稻IAPAR-9的耐旱性.结果:(1) 当叶片出现永久萎蔫时,4个水稻品种(组合)盆中土壤含水量为6.1%~8.5%,显著或极显著低于IAPAR-9盆中土壤含水量(9.2%);(2)当叶片出现永久萎蔫后3~5 d复  相似文献   
107.
To identify crop rotation systems capable of sequestering C and N to 1 metre depth in a subtropical Ferralsol of Southern Brazil managed under long‐term zero‐tillage (21 yrs), we evaluated six crop sequences: wheat (Triticum aestivum)–soybean (Glycine max) [W‐S], the baseline; oat (Avena strigosa, as cover crop)–maize (Zea mays)–wheat–soybean [O‐M‐W‐S]; vetch (Vicia villosa, as legume cover crop)–maize–wheat–soybean [V‐M‐W‐S]; vetch–maize–oat–soybean–wheat–soybean [V‐M‐O‐S‐W‐S]; ryegrass (Lolium multiflorum, for hay)–maize–ryegrass–soybean [R‐M‐R‐S]; and alfalfa (Medicago sativa, for hay)–maize [A‐M]. Compared to W‐S and to 1 metre, the hay‐based system of A‐M showed the largest C and N sequestration rates (0.50 and 0.06 Mg/ha/yr, respectively). Alfalfa, being a perennial legume under cut‐regrowth cycles, possibly added more C and N through roots. The other hay system, R‐M‐R‐S, also sequestered C efficiently (0.27 Mg/ha/yr), but not N (0.01 Mg/ha/yr). The legume‐based system of V‐M‐W‐S sequestered significant amounts of both C (0.29 Mg/ha/yr) and N (0.04 Mg/ha/yr). The grass‐based system of O‐M‐W‐S showed the lowest sequestration of C (0.09 Mg/ha/yr). In all systems, a positive relationship (R2 = 0.71) occurred between estimated addition of root C and soil C stock to 1 metre. Whenever C and N sequestration occurred, more than half of that occurred below 20 cm depth. Results suggest that adoption of legume‐based systems, perennially as A‐M or annually as V‐M‐W‐S, is efficient for C and N sequestration in subtropical zero‐tillage soils and that roots possibly contribute more to that sequestration than aboveground biomass.  相似文献   
108.
研究巴西蕉幼苗在60 mmol/L NaCl人工模拟的盐胁迫0、4、8、12、24和48 h不同时间下,通过增加外源CaCl2和钙离子螯合剂EGTA处理后,测定其叶片和根的钙调蛋白(CaM)含量的变化。结果表明,与对照处理相比,在NaCl胁迫过程中,叶片CaM含量在4、8、12 h显著增加而在24和48 h显著减少;根的CaM含量则是在4、12、24 h显著增加,在8 h显著降低。在NaCl胁迫中添加CaCl2处理能显著提高CaM含量,而在NaCl胁迫中添加EGTA处理能显著降低CaM含量。以上说明,通过  相似文献   
109.
Voluntary certification programs are one type of intervention used to incentivize the agricultural commodity sector in tropical landscapes to reduce deforestation and improve sustainability. Cases of the Roundtable on Sustainable Palm Oil (RSPO) voluntary certification program in Indonesia and the Sustainable Agriculture Network (SAN), voluntary certification for cattle in Brazil, are used to contrast the role taken in two significantly different programs to render sustainability outcomes. While producers in both countries follow a similar path toward compliance with certification standards, only the RSPO program offers enticements for producers to participate in the intermediate stages of compliance by offering membership in its affiliated industry roundtable. Design choices about the core activities of a program (adoption, implementation, and enforcement and monitoring) that are ancillary to standards setting are found to be opportunities for providing benefits to both producers and civil society stakeholders without compromising the program’s rigor. A framework is proposed to understand voluntary certification programs as both creators and brokers of benefits between producers and other sustainability stakeholders, potentially providing an approach to simultaneously increase participation and maintain program rigor.  相似文献   
110.
This study aimed to evaluate and correlate intraocular pressure (IOP), endothelial cell density (CD), and hexagonality (HEX), and the aqueous humor prostaglandin E2 (PGE2) concentration in dogs with mature (MG, n = 8) and hypermature (HG, n = 8) cataracts. Eight laboratory beagles with no ocular abnormalities were included as a control group (CG). The IOP was measured using a digital applanation tonometer. Noncontact specular microscopy was used to evaluate CD and HEX. Samples of aqueous humor were used to determine prostaglandin E2 concentration using enzyme‐linked immunoassay. Data were compared by anova and Bonferroni's multiple comparison test, and possible correlations among the PGE2 aqueous concentration and corneal endothelium cell parameters were assessed by Person′s test (< 0.05). Average values of IOP (= 0.45) and CD (= 0.39) were not significantly different between MG, HM, and CG. Average values of HEX were lower, and PGE2 concentration was increased in the MG and HG in comparison with CG (< 0.05); however, such parameters did not change significantly between MG and HG (> 0.05). PGE2 values did not correlate with IOP, CD, and HEX in any group (> 0.05). Although there were a small number of dogs studied, our results demonstrated that cataract progression from mature to hypermature did not have a significant change in PGE2 aqueous concentration, IOP, corneal endothelial cell count, or morphology. In addition, PGE2 concentration was not correlated with parameters of the corneal endothelium or IOP in dogs with mature or hypermature cataracts.  相似文献   
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