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51.
Reduced physiological efficiency as well as low and irregular germination rate under environmental stress conditions (e.g., salinity) are among the major factors affecting the propagation of numerous plants, in particular medicinal ones. A factorial experiment using a completely randomized design was employed to evaluate the effect of plant growth-promoting rhizobacteria (PGPR) on hopbush seed germination and seedling growth under salinity stress. After the seeds were inoculated with the Azospirillum lipoferum, Azotobacter chroococcum, and Azospirillum + Azotobacter and exposed to salinity stress at six levels, they were placed into a germinator at 20°C temperature and 65% relative humidity with a photoperiodic regime of 16 h light/8 h dark at 1,000 lux fluorescent light. The seeds inoculated with the bacterial strains could tolerate salinity levels of up to 50 dS/m and germinate. The combined treatment of Azospirillum + Azotobacter increased germination percentage at 20 and 50 dS/m levels by 21.67 and 10%, respectively. Also, A. chroococcum at 15 and 20 dS/m and Azospirillum + Azotobacter at 50 dS/m stress levels increased germination rate by 88, 316, and 155%, respectively, compared with the control. Furthermore, plant growth parameters—e.g., root and stem length, root and stem dry and fresh weights, as well as the ratios of root length and weight to the stem counterparts—were considerably enhanced by Azotobacter chroococcum treatment under elevated salinity stress (15 and 20 dS/m), relative to the control. Inoculation with A. chroococcum more favorably affected on and was also more compatible with Dodonaea viscosa seedlings leading to considerably improved seedlings growth parameters as well as seed germination under salinity stress.  相似文献   
52.
The goal of this study is to enumerate Campylobacter in chicken meats and by-products. In the current investigation, results showed that raw chicken meats and chicken by-products were contaminated with Campylobacter ranging from <3 to 4600 MPN·g−1. Campylobacter jejuni showed a higher number compared to Campylobacter coli in the chicken samples. The current study showed that the percentage of chicken livers and gizzards harbored a higher number of Campylobacter (103–104 MPN·g−1) than other chicken parts at 33.3% and 9.2%, respectively. The different concentrations of Campylobacter between chicken meats and chicken byproducts reflect the differences in the contamination level. The data on Campylobacter concentration in chicken meats and by-products will be useful in risk analysis.  相似文献   
53.
Pomegranate is one of the native fruits of Iran which contains high genetic resources, but there are insufficient information regarding properties of the fruit. The objective of the present study was to investigate the physcio-chemical characteristics and antioxidant activity of twenty pomegranate cultivars grown in Iran. This study showed that there were significant differences among the cultivars in all measured factors except the length/diameter ratio of fruit. The fruit weight, skin percentage, aril percentage and juice percentage were within the range of 196.89–315.28 g, 32.28–59.82%, 37.59–65% and 26.95–46.55%, respectively. The total soluble solids content varied from 11.37 (°Brix) to 15.07 (°Brix), pH values from 3.16 to 4.09, titratable acidity content from 0.33 g 100 g−1 to 2.44 g 100 g−1 and total sugars content from 13.23 g 100 g−1 to 21.72 g 100 g−1. The results also showed that the values of ascorbic acid ranged from 9.91 mg 100 g−1 to 20.92 mg 100 g−1. The total anthocyanins content was observed in pomegranate cultivars between 5.56  mg 100 g−1 and 30.11 mg 100 g−1. The level of total phenolics was varied from 295.79 mg 100 g−1 to 985.37 mg 100 g−1. The antioxidant activity of pomegranate cultivars was found between 15.59 and 40.72%. These data demonstrated that the cultivar was the main parameter which influences the physico-chemical properties and antioxidant activity in pomegranates.  相似文献   
54.
Epicuticular waxes have vital roles in the growth and development of plants and in defense. Conifers have a considerable amount of waxes on their cones and leaves.Here we characterized the n-alkane composition of Iranian conifers, including Juniperus oblonga, J. foetidissima, J.sabina, J. communis subsp. hemisphaerica, J. excelsa,Cupressus sempervirens, Platycladus orientalis from Cupressaceae and Taxus baccata from Taxaceae for the first time using GC-FID analyses. In the waxes, 25 n-alkane homologs with chain lengths ranging from C7 to C32 were identified. Short-chain n-alkanes were dominant in almost all samples with some exceptions. Complementary studies to elucidate complete wax constituents of Iranian conifers and n-alkane distribution pattern as a function of geographical and bioclimatic variables are recommended.  相似文献   
55.
56.
Summary ExpressingE. coli inorganic pyrophosphatase in transgenic plants demonstrated that long distance sucrose transport is dependent on cytosolic pyrophosphate. It was speculated that removal of cytosolic pyrophosphate would impair sucrose utilization during storage of potato tubers and thereby prevent tuber sprouting. To explore this hypothesisSolanum tuberosum var. Désirée plants were transformed with a chimeric PPa gene. FollowingAgrobacterium mediated transformation, metabolite and carbohydrate contents of growing and stored tubers were measured. There was a large accumulation of soluble sugars and a decrease of starch at all developmental stages investigated. The PPase activity in PPaII tubers was parallel with a decrease of PPa, an increase of fructose-2,6-bisphosphate and an increase of UDP-glucose. As expected the amount of hexose-6-phosphates and glycolytic intermediates decreased. As a consequence PPaII tubers did not sprout even after a prolonged storage period of two years. Since the energy status of PPaII tubers is unaltered inhibition of sprouting is most likely due to reduced sucrose export and its subsequent utilization.  相似文献   
57.
This trial was conducted to evaluate the effects of nucleotides on growth of whiteleg shrimp, Litopenaeus vannamei, and the survival and metabolic responses to ammonia stress test. Experimental diets were as follows: low fish meal diet (LFMD), and four LFMD test diets, each supplemented with 0.1% guanosine monophosphate (GMP), 0.1% inosine monophosphate (IMP), 0.1% mixture of GMP and IMP and 0.1% mixture of GMP, IMP, uridine monophosphate (UMP) and cytidine monophosphate (CMP). The shrimp specimens (initial body weight: 0.99 ± 0.01 g) were randomly allocated into five groups and fed four times daily for 8‐weeks. After the trial, final body weight was recorded and haemolymph was withdrawn for haematological analysis. The shrimp was then challenged with 70 mg/L ammonia (LC50) for 10 days. Survival and haemolymph of the shrimp were taken after exposure to ammonia. The highest growth performance was observed in the shrimp fed diet supplemented with GMP (p < .05), while survival was not influenced by the test diets in the feeding trial. In the ammonia challenge test, the highest survival was observed in the shrimp fed GMP supplemented diet compared to others. The plasma protein, glucose and cholesterol levels increased in all the treatments while triglycerides level decreased post challenge. Cortisol level recovered at day 10th after the challenge. Shrimps fed with nucleotides diets showed higher protein and glucose level compared to control groups post challenge. In general, nucleotides supplemented in the diet enhanced growth, improved stress resistance while modulating the haemolymph metabolites in L. vannamei under ammonia stress.  相似文献   
58.
Vibrio harveyi causes vibriosis in various marine aquaculture fish species, especially when they are young. The infection subsequently leads to significant economic losses for aquaculture farms. Vaccination is recommended to control this disease. This study describes the efficacy of a live attenuated V. harveyi strain MVh_vhs (LAVh) as a vaccine candidate in controlling infection by wild‐type V. harveyi (WTVh) in Lates calcarifer. A total of 240 fingerlings were divided into four groups. Group 1 was not vaccinated and was not challenged, Group 2 was vaccinated with a formalin‐killed V. harveyi (FKVh), Group 3 was vaccinated with the LAVh before challenge and Group 4 was not vaccinated and was challenged. Bath vaccination was employed for one hour before the LAVh distribution was determined in the fish mucus, gill, liver, gut, kidney and spleen. The gills, livers, kidneys and skins were also sampled for gene expression analysis. To challenge the fish, skin abrasion was conducted before the fish were challenged by immersion with WTVh. The results revealed an extensive distribution of the LAVh in the liver and kidneys of the fish in Group 3 for the first 12 hr, resulting in mild lesions compared with Group 1. Similarly, there were significantly (p < .05) higher expressions of the Chemokine ligand 4 and major histocompatibility complex I genes in the skin and liver of the fish in Group 3 in comparison with other groups. Vaccination with LAVh resulted in a significantly high rate of survival (68%) of the fingerlings after being challenged with WTVh.  相似文献   
59.
Summary In Kuwait, approximately 12,000 diary cows were vaccinated with a reduced dose of 3×109 Brucella abortus strain 19 and approximately 350,000 sexually mature sheep and goats with a reduced dose of 107B.melitensis strain Rev. 1. Using the criteria of prevaccinal and postvaccinal incidences of antibodies, abortions, and human cases of brucellosis, the programme was very successful. Widespread vaccination of adult animals is the most effective method of controlling brucellosis among cattle, sheep and goats in many countries.
Resumen En Kuwait, se vacunaron aproximadament 12,000 vacas lecheras con una dosis reducida de 3×109 organismos deBrucella abortus cepa 19 y approximadament 350,000 ovejas y cabras sexualmente maduras fueron vacunadas con una dosis reducida de 107 organismos deB. melitensis opa Rev. 1. Utilizando los criterios prevacunales de incidencia de anticuerpos, abortos, y casos humanos de brucelosis, el programa fuvo gran exito. Ef método mas efectivo de control de la brucelosis bovina, ovina y caprina an numerosas paises es la amplia utilización de vacuna en animales adultos.

Résumé Au Kuwait, environ 12,000 vaches laitiěres ont été vaccinées avec une dose réduite de souche 19Brucella abortus (3×109) et environ 350,000 moutons et chevres qui étaient matures sexuellement, one été vaccinés avec une dose réduite de soucheB. melitensis Rev. 1 (107). Basé sur la présence d'anticorps, sur le nombre d'avortements et de cas de brucellose chez les humains avant et aprés vaccination, le programme a été un succěs. La méthode la plus effective pour contr?ler la brucellose chez les bovins, les ovins et les caprins dans beaucoup de pays et de vacciner sans exception tous les animaux adultes.
  相似文献   
60.
Abstract

The germination of alang-alang rhizome buds was found to be affected by the colour of the buds, the length of the rhizome sections, and the orientation of the sections in the cultural medium.

The position of the buds on the sections did not affect the germination of the buds, nor did the differences in diameter of the rhizomes.

Subsequent growth of the buds was positively affected by increasing the lengths of the sections.  相似文献   
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