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71.
72.
Neoadjuvant treatment of canine mammary carcinomas with the progesterone receptor (PR) antagonist aglepristone has a PR expression‐related inhibiting effect on proliferation index (PI). The aim of this study was to evaluate the effect of the treatment in the disease‐free period (DFP) and overall survival (OS) of canine mammary carcinomas. Fifty female dogs with mammary carcinomas were treated with aglepristone (n = 34) or oil vehicle (n = 16) before surgery (day 15). PR expression and PI were analysed by immunohistochemistry in samples taken at days 1 and 15. Epidemiological and clinicopathological data were assessed. DFP and OS data were retrieved every 4–6 months for at least 24 months after surgery. Aglepristone treatment increased DFP of animals bearing PR+ tumours with size smaller than 3 cm, complex and mixed tumours, with histologic grades I and II, and with PI ≤ 10%. Although further studies are necessary, current evidence points to treatment with aglepristone as useful for the management of canine mammary tumours.  相似文献   
73.
Germplasm collections often include open-pollinated varieties from diverse latitudes and climatic areas that cannot be correctly conserved in a single environment. The objective of this research was to investigate if open-pollinated maize varieties from diverse latitudinal and climatic conditions could be conserved in a single location. Twelve varieties from the humid Spain, the dry Spain, and the Canary Island were multiplied in three locations from the humid Spain, one from the dry Spain, and one from the Canary Islands. Hand pollinations were made in 100-plant plots following a randomized complete block design with two replications in five locations during two years. Differences between origins and between varieties were significant for most traits, including those related to growth cycle (male and female flowering and grain moisture). The varieties from each latitudinal and climatic origin did not behave as a consistent germplasm block; contrarily, the location × variety interaction was significant for most traits. The varieties from the humid Spain maintained their ranks of growth cycle across locations and differences between varieties were more important in the dry Spain. The growth cycle of the Canarian varieties was completely different in the dry Spain. We can maintain the varieties from any Spanish environment and latitude at any location, but most varieties could be modified by natural selection for adaptation.  相似文献   
74.
  • 1. Fishing spans all oceans and the impact on ocean predators such as sharks and rays is largely unknown. A lack of data and complicated jurisdictional issues present particular challenges for assessing and conserving high seas biodiversity. It is clear, however, that pelagic sharks and rays of the open ocean are subject to high and often unrestricted levels of mortality from bycatch and targeted fisheries for their meat and valuable fins.
  • 2. These species exhibit a wide range of life‐history characteristics, but many have relatively low productivity and consequently relatively high intrinsic vulnerability to over‐exploitation. The IUCN — World Conservation Union Red List criteria were used to assess the global status of 21 oceanic pelagic shark and ray species.
  • 3. Three‐quarters (16) of these species are classified as Threatened or Near Threatened. Eleven species are globally threatened with higher risk of extinction: the giant devilray is Endangered, ten sharks are Vulnerable and a further five species are Near Threatened. Threat status depends on the interaction between the demographic resilience of the species and intensity of fisheries exploitation.
  • 4. 4. Most threatened species, like the shortfin mako shark, have low population increase rates and suffer high fishing mortality throughout their range. Species with a lower risk of extinction have either fast, resilient life histories (e.g. pelagic stingray) or are species with slow, less resilient life histories but subject to fisheries management (e.g. salmon shark).
  • 5. 5. Recommendations, including implementing and enforcing finning bans and catch limits, are made to guide effective conservation and management of these sharks and rays.
Copyright © 2008 John Wiley & Sons, Ltd.  相似文献   
75.
A total of 65 surface (0–20 cm) soil samples were collected in an effort to estimate the arsenic background values in Kavala area, Northern Greece. Arsenic was extracted by HNO3 from the <200?µm grain size fraction, and its concentrations were determined in all samples by inductively coupled plasma–mass spectrometry. Arsenic concentrations were log-transformed, and log-normal probability plots (Q–Q plots) were generated. The geochemical background was calculated as the values that lie between g/d and g?×?d (g, geometric mean; d, geometric standard deviation), which are 3.5 and 25.8 mg kg?1, respectively. The baseline value (g) was 9.5 mg kg?1. With the aid of GIS software, arsenic geochemical maps of the study area were created. The majority of the arsenic elevated concentrations were found in the proximity of the industrialized zone of Kavala.  相似文献   
76.
The absence of extraneous viruses is a requirement in the quality control of vaccines for veterinary use in the European Pharmacopoeia. A polymerase chain reaction (PCR) assay for the detection of porcine circovirus type 1 (PCV1) and type 2 (PCV2) was evaluated in 18 commercial porcine vaccines. Since vaccine components may contain PCR enhancers or inhibitors, 13 of the studied vaccines (used as diluents) were subsequently spiked with different dilutions of PCV2 and tested by PCR. Although PCV2 DNA was not detected in any of the vaccines tested, PCV1 was detected in 2/18 vaccines (11%). Eleven out of 13 PCV2 spiked vaccines showed a positive PCR result. The lack of amplification observed in two spiked vaccines suggested that use of the PCR assay to detect PCV2 could depend on vaccine composition. The results of this exploratory study have demonstrated that PCR is a rapid and fairly sensitive method for the detection of porcine circoviruses as extraneous agents in vaccine products and can be used in the quality control of pig vaccines. The study has also indicated the need for optimising the sensitivity of PCR methods for PCV genome detection in vaccine products.  相似文献   
77.
Heat treatments have been used to extend storability of several fruits, although no information is available about their effects on nutritive and functional properties in pomegranates, which was the objective of this research. Thus, pomegranate fruits were heat treated (dips at 45 degrees C for 4 min) and stored at 2 degrees C for 90 days. Every 15 days, samples were taken and further stored 2 days at 20 degrees C for shelf life study. Arils from heat-treated pomegranates exhibited higher total antioxidant activity than controls, which was correlated primarily to the high levels of total phenolics and to lesser extent to ascorbic acid and anthocyanin contents. Additionally, the levels of sugars (glucose and fructose) and organic acids (malic, citric, and oxalic acids) remained also at higher concentrations in arils from treated fruits. With this simple and non-contaminant technology, the functional and nutritive properties, after long periods of storage, could then be even greater than in recently harvested fruits, thus providing a high content in health-beneficial compounds to consumers after the intake of these fruits.  相似文献   
78.
From March 2005 to December 2007, 284 animals from 67 cattle farms (24 dairy and 43 beef) affected by bovine cysticercosis were detected in the region of Catalonia (North-Eastern Spain). Dairy farms were almost twice more likely to be affected than beef farms (OR = 1.79, 95% CI = 1.08–2.96, p < 0.05), and infected premises have a statistically significant (p < 0.05) larger number of animals when compared to uninfected farms in Catalonia.  相似文献   
79.
The suitability of trunk diameter reference baselines for irrigation scheduling of mature drip-irrigated almond trees [Prunus dulcis (Mill). D.A. Webb cv Marta] was assessed in a 3-year experiment conducted on well-watered trees in south-eastern Spain. Continuous measurements of trunk daily growth rate (DGR) and maximum daily trunk shrinkage (MDS) were carried out throughout the growing season (April–November). Day-to-day variations in MDS and DGR were related with meteorological variables. DGR was found to be weakly correlated to all the meteorological variables, while MDS showed significant relationships with most of them. The mean air vapour pressure deficit during the period 10.00–15.00 h solar time (VPDmx) was the environmental variable that best correlated with MDS. The relationships obtained were similar for all the phenological phases, except postharvest, when MDS showed a tendency towards lower values for a given atmospheric evaporative demand. The increase in trunk diameter over the 3 years also appeared to affect the relationships to some extent. As a practical procedure, it is proposed determining the baseline periodically (every 1 or 2 years) during the early stages (II–III) of the almond phenological cycle, for use as reference MDS for the subsequent growth stages, because over longer periods several factors affecting the stability of the baseline, in particular trunk diameter growth, might introduce changes in the baseline.  相似文献   
80.
A novel edible coating based on Aloe vera gel obtained according to SP Patent Filed 200302937 has been used as a means of preservation to maintain the quality and safety of cv. Crimson Seedless table grapes during cold storage and subsequent shelf life. Table grapes have a crucial economic value as a dessert fruit, but once harvested show a reduction of shelf life due to a rapid loss of quality. Uncoated clusters showed a rapid deterioration with an estimated shelf life period of 7 days at 1 degrees C plus 4 days at 20 degrees C, based on the fast weight loss, color changes, accelerated softening and ripening, rachis browning, and high incidence of berry decay. On the contrary, those clusters treated with A. vera gel significantly delayed the above parameters related to postharvest quality losses, and storability could be extended up to 35 days at 1 degrees C. Interestingly, this edible coating was able to reduce the initial microbial counts for both mesophillic aerobic and yeast and molds, which significantly increased in uncoated berries over storage. Moreover, the sensory analyses revealed beneficial effects in terms of delaying rachis browning and dehydration and maintenance of the visual aspect of the berry without any detrimental effect on taste, aroma, or flavors. To the authors' knowledge, this is the first time A. vera gel has been used as an edible coating in fruits, which would be an innovative and interesting means for commercial application and an alternative to the use of postharvest chemical treatments.  相似文献   
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