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171.
Aquatic macrophytes play a key role in nutrient cycling and in the dynamics of aquatic ecosystems. Many species have been evaluated in terms of their potential in phytoremediation processes in environments contaminated by metals. Considering this kind of application, we evaluated the potential for the bioaccumulation and biosorption of mercury by Salvinia biloba as a function of (i) different concentrations of mercury ions in the solution, (ii) the exposure time of live plants and dry biomass to the contaminant, and (iii) different pH’s, besides (iv) analyzing the effects of this metal on morphological and anatomical parameters. Bioaccumulation was evaluated by subjecting live plants to treatments with concentrations of 0.05, 0.1, and 0.2 μg.mL?1 of mercury in the solution and the control (0 μg.mL?1), at intervals of 3 days (0, 3, 6, 9, 12, and 15 days) at pH values of 5.5, 6.0, and 6.5. For biosorption, we used the dry biomass applying the same design, only changing the time intervals (0, 4, 8, 12, and 24 h). The bioaccumulated and biosorbed mercury was determined by atomic absorption spectroscopy. High values of mercury were bioaccumulated and biosorbed, and accordingly, as the concentration of mercury ions increases in the solution, the higher the value accumulated by both living plant and dry biomass. The time of exposure and the different pH values presented variation when associated with different concentrations in the bioaccumulation of mercury. Finally, few symptoms of toxicity in living plants were observed, evidencing the resistance of S. biloba to mercury and its potential use as a phytoremediation in water bodies contaminated by this metal.  相似文献   
172.
Résumé Les auteurs passent en revue les expériences effectuées en Italie au cours de trois dernières années, par vérification statistique, de la composition en acides gras du beurre de production nationale et d'importation, aux fins d'obtenir une garantie contre la possibilité de falsifications du beurre par des graisses interestérifiées.Sont ensuite examinées, pour les soumettre à l'étude par chromatographie en phase gazeuse, les analyses et les méthodes proposées pour la préparation des esters méthyliques, les techniques d'exécution du chromatogramme et les valeurs choisies pour l'élaboration du critère de pureté.
Summary The authors have reviewed the experiments that were made in Italy during the last 3 years, by a statistical checking of the fatty acid composition of national and imported butters, so as to be protected against the possibilities of adulterations by interesterified fats.Further are examined, in order to be checked by gas chromatography, the methods proposed for the preparation of methyl esters, the techniques for obtaining a chromatogram, and the values selectes for the elaboration of a purity criterium.

Zusammenfassung Mittels statistischer Nachprüfungen geben die Autoren eine Übersicht über die in Italien in den letzten drei Jahren durchgeführten Untersuchungen über die Zusammensetzung der Fettsäuren in der Landes- und Importbutter, mit der Absicht eines Schutzes gegen die Möglichkeiten einer Verfälschung mit interesterifzierten Fetten.Um eine gaschromatographische Studie zu prüfen, werden fernerhin besprochen: Die vorgeschlagenen Methoden zur Herstellung von Methylestern, die Techniken der Herstellung eines Chromatogramms und die gewählten Werte zur Ausarbeitung eines Reinheitskriteriums.
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173.
Three young, female dogs were operated for compound odontoma. All tumors were considered stage III with treatment consisting of partial mandibulectomy or maxillectomy. Microscopic examination of the resected tissue confirmed the diagnosis. Relatively aggressive, resective surgery resulted in prolonged tumor-free intervals.  相似文献   
174.
175.
A modified hemimandibulectomy was performed for treatment of oral neoplasms in 21 dogs. Intra- and postoperative evaluations included assessment of procedure difficulty, complications, mastication, cosmesis, and the time interval between surgery and recurrence of the neoplasm or clinical evidence of metastasis. Malignant melanoma was the most common neoplasm treated using this technique. The modified hemimandibulectomy was uncomplicated with minimal intraoperative hemorrhage. Three dogs had difficult mastication at 24-hours following surgery, while 5 dogs had partial wound dehiscence. Wound infection was diagnosed in 1 dog. All owners considered the postoperative outcome to provide acceptable cosmesis. Local neoplasm recurrence was documented in 5 dogs and distant (pulmonary) metastasis was diagnosed in 5 different dogs following surgery. The technical modification described in this study seemed to provide for improved mastication during the acute postoperative period compared with other hemimandibulectomy techniques performed by the authors.  相似文献   
176.
Cystinuria in Newfoundland dogs is a metabolic disease associated with a nonsense mutation in the exon 2 of the Slc3a1 gene. Similar to type I human cystinuria, heterozygote carriers are not affected by the disease and do not reveal differences in urinary concentration of dibasic amino acids when compared with normal dogs. However, through a recessive mode of inheritance, these dogs are able to transmit the disease to their offspring. Early detection of mutation carriers through cost-effective reliable methods is therefore essential for the implementation of breeding methods aimed at the eradication of the disease. Denaturing high-performance liquid chromatography (DHPLC) is a recently developed technique for rapid and efficient screening of nucleotide polymorphisms in polymerase chain reaction-amplified products. This technique was used for the identification of the C663T Slc3a1 mutation in Portuguese Newfoundland dogs. Polymerase chain reaction products amplified from a region containing the C663T locus were subjected to DHPLC analysis, and results were double checked by DNA sequencing. Results showed the presence of the mutation in 6 of the 22 dogs tested. Urine biochemical parameters correlated well with the number of mutated Slc3a1 copies, and homozygotes for the C663T mutation were the only dogs diagnosed with cystinuria. Sequence analysis confirmed the DHPLC results, demonstrating that the technique could be a reliable alternative to sequencing for the rapid and cost-effective identification of mutations in canine breeds.  相似文献   
177.
Anti-porcine circovirus type 2 (anti-PCV2) immunostaining was associated with cerebellar lymphohistiocytic vasculitis combined with hemorrhages (50 pigs) or with lymphohistiocytic meningitis (23 pigs) in pigs naturally affected with postweaning multisystemic wasting syndrome (PMWS). The animals originated from 12 farms in Rio Grande do Sul, Brazil. In total, 456 unthrifty 3- to 5-month-old postweaning pigs confirmed as PMWS cases were necropsied. Although most findings mimicked those extensively reported in PMWS-affected pigs, there were distinctive brain lesions that included multiple hemorrhages in the cerebellar leptomeninges associated with lymphohistiocytic vasculitis and fibrinoid degeneration in vessels of the cerebellum and periventricular areas (69 pigs). These vascular lesions were also seen in conjunction with lymphohistiocytic meningitis (38 additional pigs). PCV2 antigen was immunohistochemically demonstrated in the cytoplasm and nuclei from intralesional perivascular macrophages and endothelial-like cells in brain tissues. Together these findings suggest that these lesions were caused by PCV2.  相似文献   
178.
179.
The objective of this study was to determine the accuracy of early fetal sex determination by ultrasonic assessment of the relative location of the genital tubercle (GT) in goats at different stages of pregnancy as well as by the identification of fetal external genitalia. Pregnant animals were divided into three experimental groups (EI: n=21, EII: n=28, EIII: n=33). In EI, fetuses (n=27) were transrectally monitored daily from days 40 to 60 of pregnancy with a linear transducer (6.0 and 8.0MHz). In EII, fetuses (n=40) were examined once between days 45 and 70 of pregnancy by transrectal ultrasonography. In EIII fetuses (n=52) between days 100 and 120 of pregnancy, were submitted to a single transabdominal ultrasonography using a convex transducer (5.0 and 7.5MHz). Regardless of fetal sex diagnosis, 15/15 (EI), 13/16 (EII) and 9/14 (EIII) of single pregnancies and 10/12 (EI), 20/24 (EII) and 21/38 (EIII) of twin pregnancies were correctly identified. The accuracy of sex identification among EI (92.6%), EII (82.5%) and EIII (57.7%) was not statistically different (P>0.05). Identification of the GT in male fetuses was possible from day 45 onward. Changes in the GT position were not observed between days 53 and 60 of pregnancy. Accuracy of fetal sexing under field conditions is high in goats when ultrasound imaging is properly timed during pregnancy and when it is performed with proper equipment by experienced operators.  相似文献   
180.
OBJECTIVE: To evaluate adverse effects of long-term oral administration of carprofen, etodolac, flunixin meglumine, ketoprofen, and meloxicam in dogs. ANIMALS: 36 adult dogs. PROCEDURES: Values for CBC, urinalysis, serum biochemical urinalyses, and occult blood in feces were investigated before and 7, 30, 60, and 90 days after daily oral administration (n = 6 dogs/group) of lactose (1 mg/kg, control treatment), etodolac (15 mg/kg), meloxicam (0.1 mg/kg), carprofen (4 mg/kg), and ketoprofen (2 mg/kg for 4 days, followed by 1 mg/kg daily thereafter) or flunixin (1 mg/kg for 3 days, with 4-day intervals). Gastroscopy was performed before and after the end of treatment. RESULTS: For serum gamma-glutamyltransferase activity, values were significantly increased at day 30 in dogs treated with lactose, etodolac, and meloxicam within groups. Bleeding time was significantly increased in dogs treated with carprofen at 30 and 90 days, compared with baseline. At 7 days, bleeding time was significantly longer in dogs treated with meloxicam, ketoprofen, and flunixin, compared with control dogs. Clotting time increased significantly in all groups except those treated with etodolac. At day 90, clotting time was significantly shorter in flunixin-treated dogs, compared with lactose-treated dogs. Gastric lesions were detected in all dogs treated with etodolac, ketoprofen, and flunixin, and 1 of 6 treated with carprofen. CONCLUSIONS AND CLINICAL RELEVANCE: Carprofen induced the lowest frequency of gastrointestinal adverse effects, followed by meloxicam. Monitoring for adverse effects should be considered when nonsteroidal anti-inflammatory drugs are used to treat dogs with chronic pain.  相似文献   
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