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141.
Food Biophysics - Water sorption isotherm, glass transition temperature (Tg), and caking properties of maca (Lepidium meyenii Walpers) powder were investigated. A broad endothermic shift reflecting...  相似文献   
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143.
In order to better understand the range and role of Bacillus thuringiensis (Bt) and its toxins in nature, we have undertaken a study of Bt taken directly from the rectum of 117 cows from 37 farms on the Caribbean island of Trinidad. Thirty-seven fecal samples (32%) were found to contain at least one Bt. Generally only one or two isolates with a particular crystal morphology were isolated from any one sample, however, a few samples contained more, up to 11 isolates, suggesting post-ingestion amplification. Bioassays using larvae of Musca domestica, Caenorhabditis elegans and Tetrahymena pyriformis showed no observable toxicity in gross bioassays. Very small dot-like parasporal bodies, not generally characteristic of Bt, were isolated from 44% of the samples, which in many instances appeared unstable and whose relation to Bt Cry protein-containing parasporal bodies is unknown. In conclusion, we find little evidence for a host adapted strain of Bt in the cows examined, nor toxicity to organisms that might logically be associated with either the cow or its feces. The presence of a large number of isolates containing small dot-like parasporal bodies, possibly either poly-β-hydroxybutyrate storage bodies or Cry proteins, was unexpected and merits further investigation.  相似文献   
144.
Blood samples were analysed from 175 shot Iberian ibexes, and good-quality samples were obtained in more than 56% of cases. Sixty-eight of these samples from healthy animals were then used to characterize standard values for the species. Values for 10 blood parameters [monocytes, cholesterol, creatinine, albumin, beta-globulin, gamma-globulin, albumin/globulin (A/G) ratio, calcium (Ca), phosphates and iron (Fe)] from shot ibexes did not differ from those obtained from healthy captured and physically restrained animals. Blood samples from mange-infested ibexes (n=31) were also analysed and showed higher values for eosinophils and gamma-globulin than samples from healthy animals, but lower values for cholesterol, direct bilirubin, albumin, alpha-2-globulins and chloride. Values from blood parameters can provide useful information about the health and nutritional status of animals, and blood values may thus provide a complementary source of information for animals shot in Andalusia that will prove to be useful for monitoring the physiological status of ibex populations. The protocol described here provides guidelines for quick sample collection after an animal’s death and standardized instructions for sample storage, transport and analysis.  相似文献   
145.
Multiple antigen peptide constructs (MAPs) have been used to obtain defined multimeric peptide molecules useful in the development of possible synthetic malaria vaccines. In this context, a method was developed, named double dimer constructs (DDCs), involving the direct synthesis of a dimeric peptide with a C-terminal cysteine. A tetrameric molecule was then obtained by oxidation of sulfhydryl groups. Dimer synthesis was optimized using a Fmoc/tBu strategy, dimers were purified by HPLC, oxidized with DMSO and characterized by HPLC and MALDI-TOF-MS. The tetramers or DDCs obtained by this method were used as immunogens in the search for a possible malaria vaccine. It was found that they were immunogenic in the experimental Aotus monkey model, and were able to induce protective immunity when challenged experimentally with a highly infective Plasmodium falciparum malaria strain.  相似文献   
146.
Transgenic tobacco transformed with the Trichoplusia ni granulovirus enhancin gene has been demonstrated to enhance baculovirus infection in larvae. In this paper we describe the effect of the long-term feeding of lyophilized transgenic tobacco material to Pseudaletia separata and Spodoptera exigua larvae. Our results demonstrated that the baculovirus enhancin gene products have potential for use in insect pest management.  相似文献   
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148.
Morphea is a disorder limited to the skin, characterized by a stable oval plaque with a glossy plane surface that feels indurated on palpation. In contrast, systemic sclerosis is additionally characterized by disseminate cutaneous engrossment, sclerodactyly, the presence of Raynaud's phenomenon, and internal organ involvement. Human leukocyte antigen (HLA)-DR4 class Ⅱ alleles are associated with morphea in Caucasians, whereas, HLA-DR4 presents as high frequency in Amerindians, besides it was associated with autoimmune disease. The aim of this study was to determine HLA-DR alleles in Mexican patients with morphea. This study recruited 24 morphea patients, whose HLA alleles frequencies were compared with HLA alleles frequencies presented in 22 systemic sclerosis patients and 99 ethnically matched healthy controls. The HLA-DRβ1 locus was genotyped based on the hybridization technique. HLA-DR4 and DR8 frequencies showed increases in morphea patients compared with healthy controls, whereas HLA-DR4 exhibited a statistical association with morphea when allele frequencies were compared with systemic sclerosis patients. Thus, HLA-DRβ1 associations varied in morphea and systemic sclerosis, suggesting the participation of different immunological molecular mechanisms.  相似文献   
149.
From February 1992 to March 1997, 245 European mouflon (Ovis orientalis musimon) from Sierras de Cazorla, Segura y Las Villas Natural Park (southern Spain) were surveyed for oestrid larvae in order to estimate prevalence and mean intensity of parasitism by Oestrus ovis. Over 46 percent of the animals surveyed were infected, with a mean intensity of 9.6 larvae/host parasitized. No significant differences in prevalence rates between host sexes were observed, but older mouflons were infected with more larvae than younger ones.  相似文献   
150.
Changes in the vegetation of stabilized sand dunes of Doñana National Park in the last four centuries have been analysed, combining ecological and historical sources of information.Quantitative vegetation data have been obtained from 5 inventories of a 15 km long transect, consisting of 34 points where nearby woody plants have been recorded. Inventories were taken in 1636, 1647, 1652, 1682 and 1859. The analysis of these data, combined with climatic and management information on the area, reveals that until 1636 a mediterranean forest dominated byQuercus suber, existed; it was used as a game preserve. From 1636 to 1682 vegetation underwent profound changes with a marked drop in trees and mature scrub. The vegetation was replaced by a pioneer scrub species. This rapid change was brought about by the introduction of cattle and pigs, timber and cork exploitation, and the use of prescribed fire. The climatic crisis that arose circa 1700 led to erosion of the sandy soils, which made the vegetation change irreversibly. Livestock pressure hampered natural forest regeneration until 1737 whenPinus pinea plantations started. From then onwards little change in vegetation is known to have occurred.It is suggested that the main steps of change in Doñana vegetation history may have occurred in many other areas of the Mediterranean Basin.  相似文献   
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