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This report describes the morphologic and histologic features of a case of esophageal Gongylonema pulchrum infection and esophageal squamous cell carcinoma in a 17-yr-old, female vari (Lemur macaco variegates). The lemur had lived in a German zoo and had a clinical history of dyspnea, vomiting, and anorexia. At necropsy, a whitish, soft, nodular, centrally necrotic mass was found in the caudal third of the esophagus. In addition, numerous intraepithelial nematodes (G. pulchrum) were observed in the entire esophagus. Results suggest a relation between infection with G. pulchrum and development of an esophageal squamous cell carcinoma.  相似文献   
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Synchronization of the oestrous cycle of gilts using altrenogest treatment has been found to increase ovulation rate. The current experiment investigated if the increase in ovulation rate after altrenogest treatment is related to increased follicle size at the end of altrenogest treatment compared with late luteal phase follicles. Crossbred gilts (n = 15) received altrenogest during 18 days [20 mg Regumate (Janssen Animal Health, Beerse, Belgium)], starting 5-7 days after onset of first oestrus. Control gilts (n = 15) did not receive altrenogest. At days 10-12 of the oestrous cycle [i.e. in the presence of corpora lutea (CL)], average follicle development was 2.51 +/- 0.20 mm (assessed with ultrasound) in altrenogest-treated gilts and 2.58 +/- 0.16 mm in control gilts (p > 0.10). During the last days of altrenogest treatment (i.e. when CL had gone into regression), average follicle size had increased to 3.01 +/- 0.31 mm (p < 0.05). Subsequent ovulation rate was 16.6 +/- 1.7 in altrenogest treated gilts and 15.1 +/- 1.2 in control gilts (p < 0.05). Altrenogest treatment resulted in increased follicle size after regression of the CL, showing that suppression of follicle growth by altrenogest alone is less severe than suppression by endogenous progesterone (either with or without altrenogest). Altrenogest treatment also resulted in a higher ovulation rate. However, it is unclear if the increased follicle size and higher ovulation rate after altrenogest treatment are causally related, as the relation between the two on an animal level was not significant.  相似文献   
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The detection of pancreatic elastase 1 in stool samples has become the noninvasive gold standard for the diagnosis of pancreatic insufficiency in humans. Accordingly, the development of a sandwich-ELISA specific for canine pancreatic elastase 1, based on monoclonal antibodies, is presented here. The test has a detection range of 4-240 microg canine pancreatic elastase l/g feces. The intraassay coefficient of variation is 7.4%, and the interassay coefficient of variation is 7.7%. Spiking experiments show that canine elastase 1 is quantitatively detectable in fecal samples. Interestingly, the range of the elastase 1 concentration in canine feces within several days is higher as compared with humans. As the proposed cutoff of 10 microg/g is below this variation range in 96.1% of the tested samples, the effect on the test specificity is negligible. Because the test detects neither human nor bovine and porcine elastase 1, pancreatic function can be monitored without interrupting an enzyme replacement therapy.  相似文献   
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OBJECTIVES: To compare virucidal effects and bone incorporation properties of cortical bone allografts transplanted into specific-pathogen-free (SPF) cats. Allografts consisted of untreated bone from a SPF cat (negative-control group) and bone from 5 FeLV-infected cats that was subjected to sterilization with ethylene oxide (ETO), preservation with glycerol, or no treatment (positive-control group). SAMPLE POPULATION: Bones from the aforementioned groups and twenty 8-week-old SPF cats (5 cats/group) implanted with an allograft from 1 of the aforementioned groups. PROCEDURE: After implantation, blood samples were collected weekly to monitor FeLV p27 antigen and antibody titers. Quantification of FeLV provirus was performed on blood samples at weeks 0, 4, and 8 and donor bone samples at time of implantation. Cats were euthanatized 8 weeks after transplantation, and graft sites were evaluated. RESULTS: All results for negative-control cats were negative. All ETO group cats had negative results for antigen and provirus in blood, whereas 1 cat had a low antibody titer. Although 3 ETO-treated allografts were positive for provirus, the DNA appeared denatured. One cat in the glycerol group had positive results for all tests in blood samples. All glycerol-preserved allografts were positive when tested for provirus. All results for positive-control group cats were positive. Differences in incorporation of bone grafts were not observed. CONCLUSIONS AND CLINICAL RELEVANCE: Glycerol preservation of FeLV-infected bone allografts did not eliminate transmission of retrovirus to recipients. In contrast, ETO sterilization appeared to denature DNA and prevent infection. Treatments did not affect incorporation of bone grafts in young cats.  相似文献   
27.
The first European Congress on Agriculturaland Food Ethics was held at Wageningen University andResearch Center (WUR), Wageningen, The Netherlands, March 4–6, 1999. This was the inaugural conference forthe newly forming European Society for Agricultural andFood Ethics – EUR-SAFE – and around two hundredpeople from across Europe (and a handful of NorthAmericans) participated. Following theCongress/conference, a small (16 people), two-dayworkshop funded in part by the US National ScienceFoundation focused on similarities and differencesbetween the US and the EU regarding publicdiscourse/debate on food biotechnology. A briefoverview of the Congress and the follow-up workshopsuggests what lessons AFHVS and ASFS might learn fromEuropean experience of agricultural and food ethics.  相似文献   
28.
Syringa vulgaris L. inflorescences, petals, and chloroplasts, isolated from lilac flower petals, were fed with aqueous solutions of (18)O-labeled linalool and [5,5-(2)H(2)]-deoxy-d-xylose (DOX). The chloroplasts of lilac flower petals were isolated after feeding experiments with labeled precursors. Volatiles from the chloroplasts were extracted by stir bar sorptive extraction (SBSE) and analyzed using enantioselective multidimensional gas chromatography-mass spectrometry (enantio-MDGC-MS). Feeding experiments with DOX indicate that the novel mevalonate-independent 1-deoxy-d-xylose 5-phosphate/2C-methyl-d-erythritol 4-phosphate (DOX/MEP) is the decisive pathway of lilac aldehyde and lilac alcohol, respectively. Bioconversion of [(18)O]linalool into lilac aldehyde and lilac alcohol during in vivo feeding experiments was monitored, and the metabolic pathways are discussed.  相似文献   
29.
The “new” agricultural biotechnologies are presently high-priority items on the national research agenda. The promise of increased efficiency and productivity resulting from products and processes derived from biotech is thought to justify the commitment to R&D. Nevertheless, critics challenge the environmental safety as well as political-economic consequences of particular products of biotech, notably, ice-nucleating bacteria and the bovine growth hormone. In this paper the critics' arguments are analyzed in explicitly ethical terms, and assessed as to their relative merits. In some cases, a principle of “do no foreseeable harm” as well as a clear determination of likely harms would force us to conclude that research, development, and diffusion of a product or process derived from biotechnology is ethically wrong. In all cases, one conclusion that can be reached is that everyone involved in research, development, marketing and adoption of biotech products is responsible for the results of their actions; thus, each individual has a responsibility to consider a broader range of values and goals that effect and are effected by the biotechnology effort.  相似文献   
30.
The objective of this experiment was to describe the stability of airborne infectious porcine reproductive and respiratory syndrome virus (PRRSV) as a function of temperature and relative humidity. A cloud of infectious PRRSV was aerosolized using 24-jet Collison nebulizer into a dynamic aerosol toroid (DAT) maintained at a specific temperature and relative humidity. The PRRSV cloud within the DAT was sampled repeatedly over time using SKC BioSampler impingers and the total viral RNA (RT-PCR) and concentration of infectious PRRSV (TCID50) in the air samples was determined. As measured by quantitative RT-PCR, PRRSV RNA was stable under the conditions evaluated in this study. Thus, a comparison of viral RNA and Rhodamine B dye, a physical tracer, found no significant difference in the slopes of the lines. Titers of infectious virus were plotted by time and the half-life (T1/2) of infectious PRRSV was calculated using linear regression analysis. An analysis of the results showed that aerosolized PRRSV was more stable at lower temperatures and/or lower relative humidity, but temperature had a greater effect on the T1/2 of PRRSV than relative humidity. Based on these results, an equation was derived to predict the T1/2 of infectious airborne PRRSV for any combination of environmental temperature and relative humidity.  相似文献   
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