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81.
The aim of this study was to determine the content of selected elements and metabolites produced by fungi of the genus Fusarium in spelt (Triticum spelta L.) grain and husks and common wheat (T. aestivum L.) grain. Concentrations of trichothecenes, a volatile metabolite trichodiene (TRICH), as well as ergosterol (ERG) and adenosine 5′‐triphosphate (ATP) (a total microbial biomass indicator), were assessed. Toxin concentrations in spelt grain and husks harvested in 2003 and 2004 were comparable. Average deoxynivalenol concentrations reached 450 and 523 μg/kg in grain and 2,162 and 855 μg/kg in husks, respectively. Spelt grain, in comparison with common wheat grain, contained significantly higher concentrations of P, S, Mg, Zn, and Cu and a lower concentration of Al, whereas the concentrations of Ca, Fe, and Pb were significantly higher in the husks than in the grain of this cereal. A comparison of concentrations of Fusarium spp. metabolites in the grain of spelt and common wheat showed that the total concentration of mycotoxins and TRICH was slightly lower in T. spelta, whereas common wheat grain contained lower concentrations of ERG and ATP. The obtained results indicate that spelt husks contain considerable concentrations of trichothecenes.  相似文献   
82.
83.
The aim of this paper was to compare the effect of flumethasone and meloxicam in combination with oxytetracycline on clinical and immunological parameters of calves suffering from enzootic bronchopneumonia. The study was performed on 30 Black-and-White Lowland Breed calves with clinical signs of enzootic bronchopneumonia divided randomly into three equal groups and, respectively, treated with-Group I: oxytetracycline and meloxicam; Group II: oxytetracycline and flumethasone; Group III (control): oxytetracycline only. Treatment of calves with the combination of oxytetracycline and meloxicam (Group I) caused a significantly faster, in comparison to other groups, improvement in the clinical illness index score (CIIS: cough, nasal discharge, dyspnea, depression and anorexia) and a faster normalization of body temperature. A slow decrease in white blood cell (WBC) count, the number of neutrophils, MID (mixed number of monocytes, eosinophils and basophils) and in the individual number of monocytes (CD14/CD45 positive cells) was observed in Groups I and III. In the blood of the calves which received oxytetracycline and flumethasone (Group II), leukocytosis, neutrophilia and monocytosis with concomitant lymphopenia and a low number of T cells (CD2+) was observed. Moreover, the calves treated with flumethasone exhibited a decrease in gamma-globulin concentration, and phagocytic parameters. Both drugs, flumethasone and meloxicam slightly decreased tumor necrosis factor (TNF) but meloxicam slightly increased the levels of interferon (IFN) in sera and in bronchoalveolar lavages (BALs). These results suggest that the combination of meloxicam with an antibiotic in calves suffering from enzootic bronchopneumonia is superior to the antibiotic alone and also to the combination of the antibiotic with flumethasone.  相似文献   
84.
The T biotype ofBemisia tabaci (Gennadius, 1889), a population found colonizingEuphorbia characias L. plants on the Nebrodi-Peloritani mountains in Sicily, was biologically characterized. The minimum development time was 29.7 days at 28°C. Based on the regression of 1/dayvs T, the rate of development was calculated as 0.00206, the theoretical lower temperature threshold for development as 9.3°C, and the sum of effective temperatures as 485.1. At 25° C, egg-to-adult development was significantly shorter onDatura stramonium (30.1 days) than on eitherEuphorbia pulcherrima orEuphorbia characias (35.6 and 35.4 days, respectively). The fourth instar nymphs grown onD. stramonium had the typical oval outline and seven pairs of dorsal setae located on cone-like processes, often barely visible. The fourth instar nymphs and their pupal cases grown onE. characias had the outline deformed by the presence of hairs on the lower surface of the leaf. The pupae onD. stramonium were significantly larger (both longer and wider) than those reared onE. characias; on both host plants, female pupae were significantly larger than male ones. Analysis of variance showed that width of females onD. stramonium was significantly larger than the width of those reared onE. characias. Attempts at courtship between T- and Q-biotypes were observed, but adults from different biotypes were never seen mating. Only males were obtained from the seven heterologous crossing attempts, either way, whereas homologous, control breeding produced males and females. The T biotype was able to transmitTomato yellow leaf curl Sardinia begomovirus (TYLCSV) fromD. stramonium toD. stramonium, from tomato to tomato and from tomato toD. stramonium. Attempts to transmit TYLCSV fromD. stramonium to tomato were unsuccessful. The transmission efficiency was significantly lower when tomato was the test plant. The diverse biology and ecology of the T biotype confirm that it is genetically different from most Mediterranean biotypes. This paper is dedicated to the dear memory of our colleague Dr Claudio Arnò, who died on March 12, 2004, while this paper was being written.  相似文献   
85.
Despite continuing research efforts, knowledge of the transmission of the highly pathogenic avian influenza (HPAI) virus still has considerable gaps, which complicates epidemic control. The goal of this research was to develop a model to back-calculate the day HPAI virus is introduced into a flock, based on within-flock mortality data. The back-calculation method was based on a stochastic SEIR (susceptible (S) - latently infected (E) - infectious (I) - removed (= dead; R)) epidemic model. The latent and infectious period were assumed to be gamma distributed. Parameter values were based on experimental H7N7 within-flock transmission data. The model was used to estimate the day of virus introduction based on a defined within-flock mortality threshold (detection rule for determining AI). Our results indicate that approximately two weeks can elapse before a noticeable increase in mortality is observed after a single introduction into a flock. For example, it takes twelve (minimum 11 - maximum 15) days before AI is detected if the detection rule is fifty dead chickens on two consecutive days in a 10 000 chicken flock (current Dutch monitoring rule for notification). The results were robust for flock size and detection rule, but sensitive to the length of the latent and infectious periods. Furthermore, assuming multiple introductions on one day will result in a shorter estimated period between infection and detection. The implications of the model outcomes for detecting and tracing outbreaks of H7N7 HPAI virus are discussed.  相似文献   
86.
Defoliation caused annually by Cameraria ohridella has a considerable impact on the general condition of horse chestnut trees. We investigated the consequences of tree endotherapy against this insect. Wood samples, leaves and insect specimens were collected ten years after the treatment (injection) with pesticides. Insect invasion was manifested in all investigated trees by distinct radial growth depression. Treatment resulted in a growth upturn, while non-treated trees maintained decreased growth. The overall foliage infestation level was lower in treated trees, but pupal mass and potential fecundity of insect females were not affected. Our study revealed a long-lasting, positive effect of endotherapy on trees’ appearance and growth.  相似文献   
87.
An isolate of the poty virus turnip mosaic virus (TuMV-Ab) showing severe mosaic symptoms inAbutilon theophrasti from Piedmont (northwestern Italy) in 1993, has been found to be of an unusual pathotype and serotype. The isolate was easily transmitted byAphyis gossiypii and Myzus persicae and was not seed-transmitted inA. Theophrasti. The host range of TuMV-Ab was different from that of another Piedmont isolate of TuMV fromAlliaria officinalis and from a TuMV isolate fromBrassica napus. TuMV-Ab was characterized using the reactions on the fourB. Napus lines S4, R4, 165 and S1 as the rare pathotype 7, found only once previously in Europe. Tests with polyclonal antisera indicated that TuMV-Ab was only distantly related to the two other TuMV isolates. Serological characterization with a panel of 30 monoclonal antibodies showed that TuMV-Ab belonged to one of the less common serotypes (JPN).  相似文献   
88.
The organic fraction of municipal wastes has been composted on the laboratory scale. In the obtained compost the content of cadmium, cobalt, copper, manganese, nickel, lead and zinc were determined, as well as the speciation i.e, the form of their occurrence, making use of Rudd's method of sequential extraction. The investigations also concerned the way of removing these metals from the compost by means of leaching with solutions of sulphuric and nitric acid, as well as by electrochemically separating the metals from the solution after the compost had been leached with sulphuric acid. It has been found that the application of the electrochemical method with varying pH values of the leaching solution within the range of 6.8–2.8 allows for the separation of 83.5% Cd, 55.0% Co, 65.4% Cu, 59.4% Mn, 70.3% Ni, 90.5% Pb and 56.2% Zn.  相似文献   
89.
90.

Background

Astaxanthin (ASTA) is a fat-soluble xanthophyll with powerful antioxidant functions. It is extracted from e.g. salmon, an important food source for certain human populations known to have a reduced risk of tumor development. It is possible that ASTA plays a role in cancer chemoprevention in such populations. The purpose of this study was to investigate the effects of dietary ASTA on chemically induced mammary tumorigenesis using N-methyl-N-nitroso-urea (MNU) in immature Wistar rats.

Methods

Thirty-six 37 days old juvenile female Wistar rats were at random allocated to 4 groups of which Groups 1 and 2 received a single dose of 55 mg MNU/kg body weight. The effects of ASTA was evaluated by giving rats of Groups 2 and 4 a dose of 50 mg ASTA/kg/day for the entire duration of the study. Group 3 rats received feed added alimentary oil.Necropsy and histopathological examinations were carried out on each rat 14 months after the administration of MNU. Haematological values and antioxidative status were determined. Oxidative stress was evaluated by monitoring superoxide dismutase (SOD) and glutathione peroxidase (GPx) activities in hepatic tissue. Lipid peroxidation and carbonylation of proteins was determined in protein extracts from the liver.

Results

Tumor development occurred only in rats of Groups 1 and 2, i.e. MNU exposed animals. Frequency of tumor development in general and average number of tumors per animal were insignificant between these two groups. Mammary gland tumors developed in equal frequencies in Group 1 and 2 rats, respectively. Although only rather few tumors were found in the mammary glands, a substantial number of other tumors were found in Group 1 and 2 rats, but at equal rates.Biochemical analyses showed significant higher levels of GPx, malondialdehyde and dinitrophenylhydrazine in Group 1 rats that for rats in all other groups thus indicating protective effects of ASTA on MNU induced hepatic oxidative stress.

Conclusions

Supplementation with ASTA did not reduce tumorigenesis induced by MNU in Wistar rats. However, supplementation with ASTA seemed to have anti-inflammatory effects.  相似文献   
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