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281.
Echinococcus multilocularis parasitizes the small intestine of red foxes (Vulpes vulpes) and other carnivores, and has a wide distribution throughout the northern hemisphere. This cestode is the causative agent of human alveolar echinococcosis, a life-threatening helminth zoonosis. In 2000-2002, 2130 red foxes were examined for its presence in Slovakia, with a total prevalence of 30.7%. The data on occurrence were obtained by the combination of necropsy of small intestines from red foxes and coproantigen detection in faecal samples. The correlation between the number of detected specimens and the value of optical density of copro-ELISA test was found. When worm burdens were low (1-25 specimens) the sensitivity of the method was 31.3+/-8.64%, when worm burdens were >50 specimens, 81.8+/-0.66%, and with high worm burdens (>1000 specimens) the sensitivity reached 100+/-0.34%. E. multilocularis presence was detected using the nested PCR method from the eggs in the faecal samples with a 100% specificity. In epidemiological surveys of this zoonosis, it is of crucial importance to detect animals with a high level of infection, which are responsible for the bulk of environmental contamination. The advantage of copro-ELISA test lies in allowing the intravital diagnostics to be employed within the epidemiological survey of E. multilocularis occurrence in the protected and urban areas.  相似文献   
282.
Landscape diagnosis provides a bridge between scientific knowledge and socio-economic issues that is needed to meet the demands of sophisticated landscape planning and management. The diagnostic assessment of landscape functions (capacities, goods and services supported by the landscape) at different spatio-temporal scales is a valuable tool that can solve the transformation problem. A variety of landscape classification systems – including biophysical and landscape units – can be applied as a spatial reference system. Examples are described from the multitude of approaches to assess landscape functions that can be employed in landscape diagnosis. The theoretical and methodological aspects of the approach are illustrated using examples both from Germany and the Czech Republic. The examples focus on landscape functions such as groundwater recharge, regulation of water balance, and resistance to wind erosion. In addition, the rarity of and threats to landscape types, landscape aesthetic values, and the landscape character and landscape persistence are discussed.  相似文献   
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284.
Hemolivia mauritanica (Sergent et Sergent, 1904) infections were found in 14% (n= 14) of Testudo graeca Linnaeus, 1758 tortoises in Bulgaria and in 92% (n = 26) of those in Turkey. Hemolivia mauritanica-like gametocytes were found in 81% (n = 47) of wild Testudo marginata Schoepff, 1792 tortoises in Greece. Parasitaemia intensity (the percentage of infected red blood cells found in approximately 104 cells) was 0.03-22.4% in T. graeca and 0.06-12.27% in T. marginata. On the other hand, all blood samples from 40 Bulgarian, 38 Greek, and 18 Croatian specimens of Testudo hermanni Gmelin, 1789 were negative.  相似文献   
285.
Cytokine response against Salmonella Typhimurium is traditionally studied in conventional animals. Germ-free animals, however, enable to study response against infection without background effect of other microorganisms. Plasma and ileal inflammatory cytokines in germ-free piglets orally infected with virulent LT2 strain or, with a non-virulent SF1591 rough mutant were quantified by ELISA. In plasma and ileal washes, IFN-gamma levels significantly increased in both infected groups. TNF-alpha and IL-18 were mostly missing in plasma 24 h after infection. In the ileum, IFN-gamma, TNF-alpha, and IL-1beta were induced mainly by the virulent strain, whereas IL-18 was induced in highest quantity by non-virulent Salmonella. These data confirmed an important role of IFN-gamma, as well as other inflammatory cytokines in early stage of salmonellosis.  相似文献   
286.
Toxoplasmosis was diagnosed in two goat herds in the Czech Republic. The 1996 outbreak in the herd of Angora goats was associated with abortions and births of weak kids. No apparent signs of toxoplasmosis were observed in the herd of White Short-Haired (WSH) goats reared under similar conditions. Seroprevalences of 60% and 66% tested by complement fixation and indirect fluorescent antibody tests, respectively, were found in the herd of Angora goats during the outbreak of clinical toxoplasmosis. Significantly lower values were recorded in this herd in years 1994 and 1997 and in the herd of WSH goats between years 1994-1996. Iodine deficiency was also demonstrated in the herd of Angora goats in 1996. Goitre was detected by clinical examination in 39% of animals and mean urinary iodine concentration was 8.0+/-4.65 microg per 11. This concentration rose significantly to 15.7+/-5.02 microg per 11 in the subsequent year. Effects of iodine deficiency on clinical manifestation of toxoplasmosis in Angora goats were discussed.  相似文献   
287.
The preventive and therapeutic efficacy of halofuginone-lactate (HFL) against Cryptosporidium parvum was evaluated in a study conducted from November 2004 to March 2005 on a dairy farm in Central Bohemia, Czech Republic, using 260 spontaneously infected calves. HFL (0.1 mg/kg/day) was administered orally for 7 days to 1-day-old and 8-day-old calves, respectively. In both treated groups the drug significantly, and in almost the same manner, decreased the intensity of diarrhoea (P<0.001) and faecal oocyst count (P<0.001) when compared to corresponding placebo groups. The only difference between both treated groups was the time of onset of symptoms of the infection. Over time, the clinical pattern of cryptosporidiosis in the animals treated at 8-14 days of age was similar to that seen in the groups receiving the placebo. In contrast, infection in the preventively treated group peaked about 10 days later but with the same intensity. The results of this study confirm the anticryptosporidial activity of HFL in calves, but show that the outcome of infection following preventive treatment is comparable to that observed in calves treated after the onset of symptoms.  相似文献   
288.
289.
Cryptosporidium parvum is recognized as one of the most important pathogens causing enteritis and severe diarrhoea in calves up to 1 month of age. Although the infection may be responsible for some mortality, its impact is mainly associated with the impairment of intestinal functions and lower performance of animals. The aim of this study was to determine the effect of cryptosporidiosis on the intestinal functions in neonatal experimentally infected Holstein calves. Absorption tests with d-xylose and retinyl-palmitate, and the lactulose/mannitol test of intestinal permeability were simultaneously performed in 1-week intervals from challenge to full recovery. In infected animals, reduced intestinal absorptive capacity for both D-xylose and retinyl-palmitate was observed on day 7 post-infection (p.i.). At the same time, a more than 100% elevation of intestinal permeability was observed in the infected calves. All intestinal functions, except absorption of retinyl-palmitate, were significantly affected and changes were detected up to day 14 p.i. In contrast, results of all tests obtained on day 21 p.i. suggest full recovery of the infected intestine. Significantly, growth of the calves which had recovered from cryptosporidiosis was still affected between days 14 and 21 p.i.  相似文献   
290.
Enterotoxigenic Escherichia coli (ETEC) is an extracellular bacterium that causes post-weaning diarrhoea (PWD) in piglets with different severity of clinical signs. The pathogenesis of ETEC is ascribed to the effect of enterotoxins. ETEC colonizes ileum and probably can penetrate the epithelium and stimulate macrophages. The aim of study was to examine whether there is any difference in cytokine response in vitro produced by two porcine cell lines, intestinal epithelial cell line (IPI-2I) and macrophage cell line (3D4/31) after stimulation with different serotypes of ETEC associated with different clinical course of PWD in piglets. Three serotypes, O149:K88 (F4), O147:F18 and O8:K88, were used. We observed that all the used serotypes were unable to induce IL-8 and TNF-alpha mRNA expression in IPI-2I cell line as measured by the real-time RT-PCR. In 3D4/31 cell line, we detected differences in cytokine response among the used serotypes. The highest IL-8 and TNF-alpha mRNA expression in 3D4/31 was detected after stimulation with serotype O149:K88 frequently associated with hemorrhagic gastroenteritis.  相似文献   
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