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51.
52.
Effects of salinity on germination,growth and yield of cowpea   总被引:1,自引:0,他引:1  
Summary Adequate information on salt tolerance is lacking for cowpea (Vigna unguiculata (L.) Walp.), a crop grown under both dryland and irrigated conditions. A two-year field plot study was conducted to determine the responses of both the vegetative and dry seed yield of cowpea to a range of soil salinities. Four salinity levels were imposed each year on a Pachappa fine sandy loam (mixed, thermic, Mollic Haploxeralf). Vegetative growth, dry seed yield, and several components of seed yield were measured.Vegetative yield was decreased more by increasing soil salinity than was dry seed yield. Vegetative growth was reduced 9.0% for each unit increase in electrical conductivity of the soil saturation extract beyond a threshold value of 1.6 dS/m. Dry seed yield was reduced 12% for each unit increase beyond 4.9 dS/m. Fewer pods per plant accounted for nearly all of the seed yield reduction associated with increasing salinity levels.Germination was significantly reduced when electrical conductivity in sand cultures exceeded 12.0 dS/m.  相似文献   
53.
OBJECTIVE: To determine the correlates of a high-fat diet in urban, suburban and rural areas of Quebec, Canada. DESIGN: A secondary analysis of data collected as part of a 5-year multi-factorial, multi-setting, community-intervention project. SETTING: Urban, suburban and rural settings of the province of Quebec, 1997. SUBJECTS: Data were analysed from a sample of 5214 participants (2227 males, 2987 females). A food-frequency questionnaire was completed and a global index of food quality was calculated. Logistic regression was used to identify correlates of a diet high in total fats, saturated fat and cholesterol. RESULTS: In both genders, lower level of education, smoking status, French and English languages compared with other languages spoken at home, and a rural environment were associated with poor diet quality. Having no intention to eat low-fat dairy products more often was associated with a high-fat diet. In men, obesity (body mass index >/=30 kg m(-2)) and absence of reported health problems were correlates of a high-fat diet, while, in women, lower physical activity was a correlate. CONCLUSIONS: Future health interventions in Quebec should target people with low education, smokers and those living in a rural environment. Obese men and sedentary women should have access to specific dietetic resources.  相似文献   
54.
Volatile compounds were extracted by a pentane/ether (1:1) mixture from the leaves of six citrus somatic allotetraploid hybrids resulting from various combinations of lime, lemon, citron, sweet orange, and grapefruit. Extracts were examined by gas chromatography-mass spectrometry (GC-MS) and compared with those of their respective parents. All hybrids having an acid citrus parent exhibit the same relative contents in hydrocarbons and oxygenated compounds as the acid citrus, while the (grapefruit + orange) hybrid behaves similarly to its two parents. When volatile compound contents (microg g(-1)) are examined in detail, several behaviors are encountered in hybrids and seem to depend on the presence/absence of the considered parental compound and on the corresponding hybrid combination. Meanwhile, the sesquiterpene hydrocarbons are present in all hybrids at concentrations systematically lower than those of the highest parental producers. Statistical analyses show that hybrids exhibit hardly discriminable aromatic profiles, meaning that no strong dominance of one or the other parent was observed in hybrids with regards to the leaf volatile compound production.  相似文献   
55.
Summary The fate of N when incorporated in a ferrallitic soil was investigated during a 3-month incubation, using either 15N-labelled urea or 15N-labelled crop residues (sugarcane roots and leaves). The organic matter was characterized by particle-size fractionation. The urea-derived organic 15N was mainly found in the clay-sized fractions and was ascribed to biological activity. The plant-derived 15N was observed both in the sand-sized and in the clay-sized fractions; the former pool was ascribed to the persistence of crops residues, the latter to biological immobilization. The relative proportions of organic 15N recovered in the various clay fractions (coarse, fine, and very fine) were similar, irrespective of the nature of the added 15N. The very fine clay fraction (F<0.05 m) showed the highest isotopic excess, and thus gave rise to the highest turnover rate.  相似文献   
56.
Thyroid function was evaluated in 18 healthy dogs by thyrotropin (TSH) stimulation. Two dose regimens were used in each dog: 0.1 IU/kg body weight of freshly reconstituted lyophilized TSH and 1 IU/dog of previously frozen and stored TSH (up to 200 days), both given intravenously. Blood samples were collected prior to and at four and six hours after TSH administration. Serum was evaluated for total thyroxine concentrations by radioimmunoassay. All dogs were classified as euthyroid on the basis of response to 0.1 IU/kg body weight of freshly reconstituted TSH at four and six hours. The 1 IU dose of TSH, previously frozen for up to 200 days, induced increases in serum total thyroxine concentration over baseline at four and six hours that were not significantly different from those resulting from the use of the higher dose of fresh TSH. In all test groups, there were no statistically significant differences between total thyroxine concentrations at four and six hours post-TSH administration. It was concluded that an adequate TSH response can be achieved with the use of 1 IU of TSH/dog for clinically normal dogs between 29.0 kg and 41.6 kg body weight, even if this TSH has been frozen at -20 degrees C for up to 200 days. Further, blood collection can be performed at any time between four and six hours. Similar studies are needed to evaluate this new protocol in hypothyroid dogs and euthyroid dogs suffering nonthyroidal systemic diseases.  相似文献   
57.
Thoracic radiographs from 22 neonatal foals were reviewed to investigate the radiographic appearance of the thorax in normal, immature, and septicemic foals, and in foals with neonatal respiratory distress syndrome. The size and radiographic appearance of intrathoracic structures and abnormal lung opacities were evaluated. The craniocaudal and apicobasilar dimensions of the heart were 5.6–6.3 and 6.7–7.8 times the length of a midthoracic vetebral body, respectively, in normal, immature and septicemic foals. Apicobasilar measurements were greater (8.0–8.7) in the foals with respiratory distress syndrome. Normal foals had clear lung fields within 12 hours of birth. A more marked interstitial pattern was observed in immature and septicemic foals compared to normals. Diffuse air–space (alveolar) pattern with air bronchograms was seen in foals with respiratory distress syndrome. It was concluded from this series that thoracic radiographs taken 24–48 hours after birth may aid differentiation of normal foals, septicemic or immature foals, and foals with respiratory distress syndrome.  相似文献   
58.
The efficacy and field safety of marbofloxacin (Zeniquin) for the treatment of superficial and deep bacterial pyoderma were evaluated. Seventy‐two dogs were treated with 2.75 mg kg?1 of marbofloxacin orally once daily for 21 or 28 days. Sixty‐two dogs (86%) had superficial pyoderma and 10 (14%) had deep pyoderma. A history of prior pyoderma was reported in 39/72 dogs. Pretreatment aerobic bacteriologic cultures of skin lesions were performed in 47 cases and the predominant pathogen isolated was Staphylococcus intermedius. Treatment was successful in 62/72 (86.1%) dogs, improvement was noted in 6/72 (8.3%) dogs and treatment failed in 4/72 (5.6%) dogs. Adverse effects associated with treatment included listlessness, anorexia, vomiting, soft stool, flatulence and polydipsia; these adverse effects were seen in only 6/81 dogs. Marbofloxacin was safe and effective for the treatment of superficial and deep pyoderma in dogs at the dosage used in this study.  相似文献   
59.
In the present work, we studied the acute phase protein response after experimental virus infection in pigs. The animals were experimentally infected with African Swine Fever (ASF) or Aujeszky's disease (AD) viruses. The clinical course of ASF infection correlated with increasingly high levels of pig Major Acute-phase Protein (pig-MAP) (mean value of 6 mg/mL on day 6 post infection (p.i.), from 6 to 9 times higher than day 0) and sharp apolipoprotein A-I (apo A-I) decrease (mean value of 0.5 mg/mL, from 4 to 10 times lower than day 0 on day 4 p.i.). AD-clinical signs appeared at day 3 p.i., both in vaccinated (moderate clinical signs) and non-vaccinated pigs (severe outcome within 48 h p.i.). Pig-MAP and apo A-I profiles also followed clinical signs (changing from 0.70 mg/mL to around 3 mg/mL and from around 3 mg/mL to 0.96 mg/mL, respectively in non-vaccinated animals), with minor changes in concentration in the vaccinated group. Haptoglobin levels significantly increased in ASF and AD infected animals (mean maximum values of 2.77 and 3.96 mg/mL, respectively). Minor differences for the C-Reactive Protein in the case of ASF were observed, whereas its concentration increased more than 7 times in AD-infection. The albumin level was not modified in either case. The correlation of clinical signs to our data suggests the potential use of pig-MAP and apo A-I in monitoring infections in swine.  相似文献   
60.
Résumé Lorsque l'on traite des huiles végétales brutes par de l'eau, de la vapeur d'eau, des solutions salines ou des solutions acides, dans des conditions que la technique industrielle précise, il se sépare une phase aqueuse dite phase de démucilagination. Celle-ci contient des substances dotées de propriétés tensioactives comparables, mais de constitutions chimiques très différentes: des polyholosides qui représentent les mucilages proprement dits, mais aussi des phosphoaminolipides de natures diverses. De plus, des lipides simples: glycérides, acides gras libres et matières insaponifiables peuvent être entraînés dans ce milieu doté de propriétés émulsives.La présente étude est consacrée à l'analyse des produits de démucilagination, obtenus au laboratoire par action d'une quantité d'eau limitée sur l'huile brute extraite du germe de maïs.On sépare d'abord les glucides de l'ensemble lipidique en solubilisant celui-ci par un lavage avec de l'hexane. La solution est séchée, évaporée sous pression réduite et soumise à l'analyse chromatographique sur plaque de Kieselgel de Merck. Après les manipulations d'usage, la mise en évidence des taches pouvait être obtenue au moyen de la vapeur d'iode ou par pulvérisation d'acide sulfurique. Nous avons préféré utiliser la rhodamine B qui nous a permis de mettre en évidence, près de la base, une série de quatre tâches correspondant à des lécithines, (ce fait a été vérifié en soumettant la matière première à l'hydrolyse, ce qui a permis de mettre en évidence la seule choline sans trace d'éthanolamine, constituant caractéristique des céphalines), et près de la ligne de front d'autres dépôts, qui repris, ont été identifiés à des stérols. Il a été vérifié que glycérides et acides gras ne migrent pas dans nos conditions expérimentales.En complément de la chromatographie sur plaques, la chromatographie gazeuse a permis de connaître l'identité des acides gras consituant les lécithines et celle des stérols.
Summary When raw vegetable oils are treated by water, vapour, solutions of salts or acids, in conditions that are defined by industrial technique, an aqueous phase, called de gumming phase is separated. This phase contains substances possessing compared surface-active properties but differing by their chemical constitutions: poly holosides, which are the gums proper, but also phospho aminolipids of various nature. Furthermore, simple lipids: glycerides, free fatty acids, unsaponifiables may be drawn into this medium endowed with emulsifying properties.The present study is concerned with the analysis of the products of degumming obtained in the laboratory by the action of a limited quantity of water on the raw oil extracted from corn germ.First the carbohydrates are separated from by the complex of lipids by solubilizing it with a washing by hexane. The solution is dried, evaporated under reduced pressure, and chromatographically analyzed on aMerck Kieselgel plate. After the usual manipulations the evidencing of the spots could be obtained with the help of iodine vapours or by spraying with sulphuric acid. We preferred to use Rhodamin B which enabled us to show, near the base, a series of four spots corresponding to lecithins (this fact was verified by the hydrolysis of the raw material which enabled us to isolate only the choline, without any trace of ethanolamine, a characteristic constituant of cephalins), and near the front line, other spots, which, when redissolved, were identified as sterols. It was verified that in our experimental conditions the glycerides and fatty acids do not migrate.As a supplement for plate chromatography, gas-chromatography has enabled us to identify the fatty acids constituting the lecithins, and also to identify the sterols.

Zusammenfassung Wenn man die rohen Pflanzenöle mit Wasser, Wasserdampf, Salzlösungen oder Säurelösungen unter den Bedingungen der präzisen industriellen Technik behandelt, scheidet sich eine wässerige, sogenannte Entschleimungsphase aus. Diese enthält Stoffe, die vergleichbare tensioaktive Eigenschaften haben, aber deren chemische Beschaffenheit sehr verschieden ist: Polykolloide, welche die eigentlichen Schleime bilden, aber auch Phospho-amino-Lipide verschiedener Natur und auch einfache Lipide: Glyceride, freie Fettsäuren und nicht verseifbare Stoffe, die in diesem mit emulgierenden Eigenschaften ausgestattetem Medium weggespült werden können. Diese Arbeit ist der Analyse der Entschleimungsprodukte gewidmet, die im Laboratorium durch Einwirkung einer beschränkten Menge Wassers auf rohes Öl aus Maiskeimen entstanden ist.Man scheidet zuerst die Kohlenhydrate aus der Gesamtheit der Lipide aus, die durch Waschen mit Hexan lösbar gemacht werden. Die Lösung wird getrocknet, unter reduziertem Druck verdampft und der chromatographischen Analyse auf Kieselgel vonMerck unterworfen. Nach den üblichen Behandlungen wurden die Substanzflecken durch Joddampf oder Besprühen mit Schwefelsäure sichtbar gemacht. Wir bevorzugten Rhodamin B weil wir mit diesem Entwicklungsreagenz eine Reihe von vier Flecken in Startnähe erkennen konnten, die den Lecithinen zugeordnet wurden. (Es handelt sich um Lecithin, da bei der Hydrolyse des Rohmaterials nur Cholin und keine Spur Äthanolamin, dem charakteristischen Bestandteil der Kephaline, gefunden wurde.) In der Nähe der Front lagen Substanzflecken, die sich als Sterole identifizieren ließen. Es konnte nachgewiesen werden, daß Glyceride und Fettsäuren unter den Versuchsbedingungen nicht wandern.Als Ergänzung zur Chromatographie auf Platten hat die Gaschromatographie die Identifizierung der Fettsäuren, welche die Lecithine bilden, und der Sterole ermöglicht.
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