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21.
OBJECTIVE: To document clinicopathologic, histologic, and toxicologic findings in cats inadvertently exposed to pet food contaminated with melamine and cyanuric acid. DESIGN: Case series. ANIMALS: 70 cats from a single cattery inadvertently fed contaminated food that was the subject of a March 2007 recall. PROCEDURES: Clinical signs, clinicopathologic and histopathologic findings, and results of toxicologic analyses were recorded. RESULTS: Clinical signs were identified in 43 cats and included inappetence, vomiting, polyuria, polydipsia, and lethargy. Azotemia was documented in 38 of the 68 cats for which serum biochemical analyses were performed 7 to 11 days after consumption of the contaminated food. One cat died, and 13 were euthanized. Histologic examination of kidney specimens from 13 cats revealed intratubular crystalluria, tubular necrosis with regeneration, and subcapsular perivascular inflammation characterized by perivascular fibroplasia or fibrosis and inflammation with intravascular fibrin thrombi. Toxicologic analyses revealed melamine and cyanuric acid in samples of cat food, vomitus, urine, and kidneys. CONCLUSIONS AND CLINICAL RELEVANCE: In cats unintentionally fed pet food contaminated with melamine and cyanuric acid, the most consistent clinical and pathologic abnormalities were associated with the urinary tract, specifically tubular necrosis and crystalluria.  相似文献   
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Foodborne disease caused by Salmonella is of public health and economic significance. In order to assess the practical effectiveness of a new intervention strategy, experimental chlorate preparations (ECP) were administered via the drinking water to weaned and finished pigs that had been orally challenged the previous day with 10(9)-10(10) colony-forming units of Salmonella serovar Typhimurium. After 24 or 36 h ad libitum access to 0X, 1X or 2X ECP treatment (where X is the concentration estimated to deliver a minimal daily effective dose), the pigs were euthanized and gut contents and lymph tissue collected at necropsy were cultured for the challenge Salmonella. Drinking water administration of ECP effectively reduced (p < 0.05) caecal Salmonella concentrations and, with the weaned pigs, tended (p < or = 0.10) to reduce rectal Salmonella concentrations. No negative effects of ECP treatment on water intake and animal wellbeing were observed and only marginal effects on gut fermentation characteristics occurred. The bactericidal effect of administering ECP in drinking water was relatively rapid, with reductions in caecal Salmonella concentrations occurring within 24 h. These results suggest that ECP administered to pigs just days before slaughter may reduce gut concentrations of Salmonella; however, the impacts of such reductions on slaughter hygiene have yet to be determined.  相似文献   
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Inflammatory adhesions between reticulum and ventral abdomen in patients suffering traumatic reticuloperitonitis (TRP) may induce a massive inhibition of reticular contractions and thereby an impairment of the separation process of particles in the reticulorumen. However, a substantial disturbance of digesta passage (Hoflund-syndrome) is found only in a few TRP-cows. We hypothesized that this is due to a retrieval of reticular motility due to rebuilding and degradation of adhesions within months after the removal of the foreign body as the primary inflammatory stimulus. Accordingly, it was the objective of this study (a) to assess the extent and structure of inflammatory adhesions in cows with TRP over a period of six months following surgery and (b) to persecute reticular function by characterizing the sequence of reticular contractions sonographically and by assessment of particle size distribution in the faeces of patients by means of wet-sieving. Twenty-six cows suffering from TRP were studied on the day of rumenotomy (day 1) and on day 6, day 12 and 6 months post operationem. Additionally, six healthy control cows were investigated once. All cows were on a hay and concentrate diet. On day 1, the reticular floor and the reticular wall were affected by adhesions in varying extent in all cows; the contraction distance and contraction velocity of the reticulum were markedly reduced and the portion of large particles in the faces increased compared to healthy cows. On day 12, the portion of large particles did not vary any more from that of control cows; a tendency towards an increased contraction distance compared to day 1 was found. Sonographically, only marginal differences were detected in respect to extent and consistency of adhesions. Six months after rumenotomy, in 9 of 16 re-investigated cows sonography revealed no adhesions at the reticulum at all, in other cases the extent of adhesions shrunk considerably. Contraction distance and contraction velocity and particle size distribution in the faeces were found to be nearly comparable to that of control cows. It is concluded that inflammatory adhesions disappear in the majority of the TRP-patients, as a consequence reticular function normalizes. A serious disturbance of digesta passage seems to develop exclusively in those patients with the most extensive adhesions and may be also in such cows, where the primary adhesions cause the development of extensive abscesses.  相似文献   
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The niobium-92-zirconium-92 ((92)Nb-(92)Zr) extinct radioactive decay system (half-life of about 36 million years) can place new time constraints on early differentiation processes in the silicate portion of planets and meteorites. Zirconium isotope data show that Earth and the oldest lunar crust have the same relative abundances of (92)Zr as chondrites. (92)Zr deficits in calcium-aluminum-rich inclusions from the Allende meteorite constrain the minimum value for the initial (92)Nb/(93)Nb ratio of the solar system to 0.001. The absence of (92)Zr anomalies in terrestrial and lunar samples indicates that large silicate reservoirs on Earth and the moon (such as a magma ocean residue, a depleted mantle, or a crust) formed more than 50 million years after the oldest meteorites formed.  相似文献   
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Enzootic calcinosis was diagnosed in 16 cows, which originated from 6 dairy farms located in the Unterengadin valley in Switzerland between 1,402 and 1,650 metres above sea level. During the winter, the cows were fed haylage, which contained up to 50 per cent golden oat-grass (Trisetum flavescens), and hay and grain. The first symptoms of enzootic calcinosis were noted in March 1998, when some of the cows developed locomotor abnormalities. Additional cases were diagnosed during the following three months. The most important clinical findings were decreased milk production, weight loss, frequent recumbency, difficulty in rising, kneeling while rising and feeding, stilted gait, arched back, shifting weight from one foot to another and reluctance to remain standing after being roused. Of the 16 cows, 5 had elevated concentrations of serum calcium and 10 had decreased concentrations of serum magnesium. All cows had normal or decreased concentrations of serum phosphorus, because the feeding of haylage containing golden oat-grass had been discontinued two months previously. In all of the cows, the most important postmortem findings were severe calcification of the aorta, iliac artery, brachiocephalic trunk and pulmonary artery.  相似文献   
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Warmeling of samples of marine sediments to room temperatures prior to the extraction of interstitial water accounts for the apparent enrichments of potassium ion (13.3 percent) and chloride ion (1.4 percent) and depletions of magnesium ion (2.5 percent) and calcium ion (4.9 percent). These differences are the result of changes in ion-exchange selectivity as a function of temperature.  相似文献   
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N,N'-Dibutylurea (DBU) is a breakdown product of benomyl [methyl 1-(butylcarbamoyl)-2-benzimidazole carbamate], the active ingredient in Benlate fungicides, and has been proposed as one cause for crop damage that growers claim to have occurred from the use of Benlate 50 DF fungicide. This study assessed DBU formation upon (1). application of n-butyl-1-[(14)C]butylisocyanate (BIC), the immediate precursor to DBU formation, in four soils at two water potentials (0.03 and 0.1 MPa) and (2). application of benomyl butyl-1-(14)C-benomyl enriched Benlate DF and SP fungicides to two soils at various combinations of negative water potential (0.03 or 0.1 MPa) and temperature (23 or 33 degrees C). Parent compounds, metabolites, and (14)CO(2) were tracked using chromatographic analysis with radioassay and UV detection, liquid scintillation counting, and postextraction oxidation of the soil. At 0.03 MPa in all four BIC-treated soils, DBU formation was never detected. At 0.1 MPa, DBU was detected in two soils, but at concentrations <3.6 microg kg(-)(1) (0.3 wt % of applied BIC). In both soils treated with benomyl formulations, DBU formation was observed with only Benlate 50 DF application at 0.03 MPa and 23 degrees C, which was followed by rapid dissipation of DBU. The maximum concentration observed was 0.41 microg g(-)(1) (0.65 wt % of applied benomyl at 62.8 microg g(-)(1)), which is well below levels currently reported to cause adverse effects to plants. Combined benomyl and carbendazim half-lives in soils across treatments were 2-3 months. This study demonstrated that further production and accumulation of DBU in soils after Benlate application or from residual benomyl remaining in the soil are highly unlikely and that persistence of any DBU in soils is likely to be short-lived.  相似文献   
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Pools and fluxes of N in wetland vegetation and soils were compared with an adjacent upland site to assess the relative importance of wetland versus upland landscapes in watershedN-retention in the Adirondack Mountains of New York (U.S.A.).The majority of N storage occurred in forest soils and wetlandpeat deposits (96 and 99% of total N in upland forests andwetlands, respectively). Annual N-uptake (49 kg N ha-1yr-1) was greater for wetland vegetation than that ofupland vegetation (30 kg N ha-1 yr-1). In the wetlandthe supply of N from mineralization (36 kg N ha-1yr-1) was less than N-uptake; in contrast, upland Nmineralization (76 kg N ha-1 yr-1) exceeded Nvegetation uptake. Annual N-storage in peat was small due to low peat accretion rates. Wetlands acted as a sink for N andstored a disproportionally high fraction (15%) of catchment Nin relation to their relatively small surface area (~4%)within the catchment.  相似文献   
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