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Resume Il existe une très grande différence dans la réponse des légumes-feuilles et des légumes-fruits aux différents traitements agronomiques.Les premiers présentent de grandes variations dans la composition minérale et vitaminique suivant les niveaux de nutrition.Chez les seconds, par contre, les influences variétales et de niveaux de nutrition sont très tamponnées. Seul l'âge de la plante a une influence importante sur les compositions minérales et vitaminiques.
The influence of some cultivation procedures upon mineral and vitamin content of vegetables grown in glass houses
The production of vegetables under glass is rising in France and covers an appreciable part of the out-of-season demand for vegetables.It appeared to us to be important to carry out a detailed study of vitamin and mineral composition of tomatoes and salad crops grown under these special cultivation conditions.The glasshouse climate has a considerable influence upon the physiology of the plants and thus upon the content of inorganic and organic compounds in the green parts of the plant as well as the fruit which serve as food.Comparative measurements were carried out throughout the vegetative period of different varieties of these vegetables under different fertilizer regimes.

Zusammenf Assung Die Gemüseproduktion in Gewächshäusern steigt in Frankreich an und deckt einen wesentlichen Anteil des Gemüsebedarfs außerhalb der Freilandsaison.Es erschien uns daher wichtig, unter Berücksichtigung der besonderen Kulturbedingungen, eine detaillierte Bestandsaufnahme der Vitamin- und Mineralzusammensetzung von Tomaten und Salat, die unter diesen Bedingungen herangezogen wurden, vorzunehmen.Tatsächlich verändert das Gewächshausklima die Physiologie der Pflanzen beträchtlich und damit auch die Anteile anorganischer und organischer Stoffe sowohl in den grünen Organteilen als auch in den Früchten, die dem Verzehr dienen.Vergleichsuntersuchungen wurden während der ganzen Vegetationsperiode zwischen verschiedenen Sorten dieser Gemüse, bei unterschiedlichen Düngergaben durchgeführt.


Exposé présenté à l'occasion du congrès de l'Association Internationale de Recherches sur la Qualité des Plantes Alimentaires (CIQ) et la Deutsche Gesellschaft für Qualitätsforschung (Pflanzliche Nahrungsmittel) e.V. (DGQ) à Berlin le 5 Octobre 1972.  相似文献   
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The investigation was carried out to study the impact of melatonin and L-tyrosine administration on the onset of cyclicity in delayed pubertal ewe-lambs. Fifteen delayed pubertal ewe-lambs (age >16 months) were used in this study after being assigned randomly into three groups. In the first group (melatonin treated group, n = 5), each lamb was administered 3 mg melatonin orally at 16:00 hours from 1 July to 15 September while in the second group (L-tyrosine treated group, n = 5), each lamb was administered L-tyrosine at the level of 100 mg/kg b.w. as a single oral dose. The third group (n = 4) served as control. Lambs were exposed to mature, fertile rams daily and blood samples were collected twice weekly. The progesterone concentrations (P4 evaluations) were significantly higher (p < 0.05) in treated groups than the control group. Ovarian activity, assessed by P4 evaluations, showed that all animals in the first group came in oestrus and from them four got pregnant (80%) while in the second group, only three lambs came in heat and from them two became pregnant (40%). On the contrary, none of the control lambs showed oestrus. In conclusion, this study confirmed that the oral administration of melatonin and L-tyrosine played an essentially physiological roles to induce cyclicity in delayed pubertal ewe-lambs and improved their reproduction.  相似文献   
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BACKGROUND: Angiotensin-converting enzyme inhibitors (ACEIs) improve quality of life and extend the life span of dogs with naturally acquired ISACHC class II-III congestive heart failure (CHF). However, their effects on asymptomatic heart disease remain controversial. HYPOTHESIS: Benazepril (BNZ), an ACEI, could have beneficial effects at the asymptomatic stage of degenerative mitral valve disease (MVD). ANIMALS: Dogs with ISACHC class Ia MVD and moderate-to-severe mitral regurgitation (MR) assessed by the color Doppler mapping technique at entry (Day 0) were retrospectively included. METHODS: Dogs were assigned to the treated group (BNZ group) if they received BNZ (and no other cardiac medication) from Day 0 or to the untreated group (UT group) if they did not receive any cardioactive treatment until occurrence of CHF. RESULTS: A total of 141 dogs were included in the study, 66 in the BNZ group (dosage: 0.30 +/- 0.13 mg/kg) and 75 in the UT group. In the population (n = 93) including all breeds except Cavalier (CKC) and King Charles Spaniels (KC), median survival time to all causes of death in the BNZ group (n = 34, 3.3 years) was significantly longer than in the UT group (n = 59, 1.9 years) as was time to cardiac event (P < .05). Conversely, no effect of the BNZ treatment was observed in the CKC and KC population. CONCLUSIONS AND CLINICAL RELEVANCE: BNZ had beneficial effects in asymptomatic dogs other than CKC and KC affected by MVD with moderate-to-severe MR. Breed distribution should be taken into account for interpretation of clinical trials performed in dogs with cardiac disease.  相似文献   
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Infection and colonization with methicillin-resistant Staphylococcus aureus (MRSA) are now increasingly being reported in animals and people who work with animals, including horses and horse personnel. The objectives of this study were to evaluate the prevalence of MRSA colonization in veterinary personnel attending an international equine veterinary conference, and to identify risk factors for MRSA colonization in this group. Volunteers were recruited at the conference to provide a single nasal swab and complete a questionnaire regarding contact with the human health care system, contact with horses, and personal hand hygiene. Colonization with MRSA was found in 26/257 (10.1%) of study participants. Multivariable analysis showed an increased risk of MRSA colonization associated with having been diagnosed with or having treated a patient diagnosed with MRSA colonization or infection in the last year (odds ratio [OR] 8.41, 95% confidence interval [CI] 1.51–49.92, P = 0.015; OR 3.27, 95% CI 1.05–10.11, P = 0.039, respectively), whereas hand washing between infectious cases (OR 0.27, 95% CI 0.11–0.72, P = 0.009) and hand washing between farms (OR 0.35, 95% CI 0.14–0.98, P = 0.047) were protective. The prevalence of MRSA colonization among equine veterinary personnel found in this study was high compared to that of other studies of the general population. These data support previous suggestions that equine veterinary personnel are at increased risk of colonization with MRSA. This is the first study to demonstrate a statistically significant association between hand hygiene practices and a measurable clinical outcome in veterinary medicine.  相似文献   
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Geographic information system and remote sensing technologies were used to identify landscape features associated with risk of West Nile virus transmission as defined by the presence of confirmed horse cases. SPOT-4 images of Camargue area were used to generate a map of landscape categories of epidemic foci and the geographic information system was employed to determine the proportion of landscape components surrounding 10 horse case sites and 17 control sites. The spatio-temporal analysis of the cases outbreak gave the best results for a spatial window of 9 km and a temporal window of 18 days. Two clusters were identified (relative risk=3.35), both in the wet area of Camargue, near the town "Les Saintes Maries de la Mer". The first one was 4 km radius, the second 9 km. The relationships between the presence of cases and proportions of landscape categories were analyzed using generalized linear model. The best model indicated that rice fields and dry bushes, wet "sansouire" and open water were the major components of the landscape that were associated with the presence of West Nile virus cases.  相似文献   
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Unexpected, biologically salient stimuli elicit a short-latency, phasic response in midbrain dopaminergic (DA) neurons. Although this signal is important for reinforcement learning, the information it conveys to forebrain target structures remains uncertain. One way to decode the phasic DA signal would be to determine the perceptual properties of sensory inputs to DA neurons. After local disinhibition of the superior colliculus in anesthetized rats, DA neurons became visually responsive, whereas disinhibition of the visual cortex was ineffective. As the primary source of visual afferents, the limited processing capacities of the colliculus may constrain the visual information content of phasic DA responses.  相似文献   
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