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51.
A unique flower initiation of the wild Junebearing strawberry strain ‘CHI-24-1’ in Fragaria chiloensis occurs under 24 h DL and high temperature conditions. To introduce the floral initiation characteristics of ‘CHI-24-1’ into cultivated strawberries of F. × ananassa, a cross pollination was conducted between ‘CHI-24-1’ and the Japanese short-day type strawberry cultivar ‘Nyoho’. The floral initiation of ‘CHI-24-1’ was induced in both parent and daughter plants linked with runners under a 24 h DL and 23/20 C, but not 8 and 16 h DLs at the same temperatures. Of the 21 F1 hybrids grown under the 24 h DL, 12 showed flower truss production in the parent and/or daughter plants linked with runners. Among 64 F1 hybrids, 26 exposed to 8, 16 and 24 h DLs for 30 days produced no flower trusses. However, 32, one and five F1 hybrids produced flower trusses under the 24 h DL alone, 8 h DL alone and both the 8 and 24 h DLs, respectively. The results of the experiments indicated that none of the F1 hybrids were day-neutral plants, but approximately 60% had the characteristics of floral initiation under 24 h DL, which was inherited from the pollen parent of ‘CHI-24-1’. The importance of the unique floral initiation characteristics under 24 h DL with high temperature for strawberry breeding was discussed.  相似文献   
52.
53.
This prospective study evaluated seroepidemiologic features of canine respiratory coronavirus (CRCoV), canine parainfluenza virus (CPIV), and Bordetella bronchiseptica infections in dogs in an urban humane shelter and in rural/small community dog populations in western Canada. Seroprevalence of CRCoV and CPIV was low compared with other countries; seroprevalence of B. bronchiseptica was moderate to high in most populations examined. Rural dogs were 0.421 times (P ≤ 0.0001) less likely to be positive for CRCoV than dogs admitted to the shelter. There were no statistical differences in prevalence of antibodies to B. bronchiseptica and CPIV between urban and rural populations. Dogs from Fort Resolution, NWT were significantly (P < 0.05) less likely to have moderate or high antibody titers to the 3 agents than dogs in the shelter. Seroconversion to CRCoV was common in dogs in the shelter, but was not associated (P = 0.18) with respiratory disease. Antibodies to CRCoV, CPIV, or B. bronchiseptica on arrival were not significantly (P > 0.05) associated with disease-sparing after entry into the shelter.  相似文献   
54.
Glucocorticoid (GC) administration with or without other chemotherapeutic reagents is a commonly used option in the treatment of mast cell malignancies. However, the responsiveness of mast cell tumors to GC treatment varies in individuals, and the regulatory mechanisms determining the GC sensitivity of malignant mast cells remain unclear. Since the expression of the GC receptor (GR) has been reported to be associated with GC sensitivity in human neoplastic lymphocytes, we attempted to investigate the relationship between GR levels and GC sensitivity by using neoplastic mast cells derived from canine mast cell tumors (MCTs). To elucidate the regulatory mechanisms involved in GC responsiveness, we analyzed various canine MCT cell lines and tissue samples from dogs with MCT. While the proliferation of canine MCT cells was suppressed by the addition of GC to the culture, we found that MCT cells derived from humans and rodents, as well as canine lymphoma cells, responded poorly to GC. However, there were also some variations in responsiveness to GC treatment among canine MCT cell lines used in this study. Using real-time polymerase chain reaction and Western blot analysis, we elucidated the relationship between GR expression and responsiveness to GC in canine MCT cells. Furthermore, to assess the involvement of GR expression in GC sensitivity in vivo, clinical investigations were conducted on dogs with cutaneous MCT. Written informed consent was obtained from owners, and the affected dogs were treated with prednisolone (0.5-2.0 mg kg(-1)day(-1), administered orally) 1 or 2 weeks prior to the surgical removal of the tumors. Tumor volume was measured according to WHO criteria both before and after prednisolone treatment, and the GC sensitivity of each MCT was determined on the basis of the reduction in tumor volume. Of the 15 dogs with MCT, 11 responded to treatment with prednisolone completely or partially, whereas 4 dogs showed no response. Examination of clinical samples obtained by surgical removal revealed that GR expression levels were significantly lower in GC-resistant MCT tissues than in GC-sensitive MCT tissues. Thus, these results strongly indicate that GR expression may contribute to GC sensitivity in canine MCT.  相似文献   
55.
A simple capillary electrophoretic method is described for the simultaneous determination of soluble oxalate and nitrate in forage grasses. Grass samples were ground and extracted with water. The extracts were filtered and submitted to capillary electrophoresis. Electrophoresis was performed in a 75 microm x 50 cm fused silica capillary with 30 mM sodium sulfate containing an electroosmotic flow modifier under constant voltage at -8 kV. Separated oxalate and nitrate were detected with direct UV absorption at 214 nm. The present method can be used for routine monitoring of the concentration of soluble oxalate and nitrate in grasses.  相似文献   
56.
Ovaries contain follicles at various stages of development, including primordial, primary, secondary, antral and Graafian follicles. Although the growth of these follicles is controlled to maintain regular ovulation, the mechanism through which this occurs remains unclear. In our study, we found that the growth rate of cultured secondary follicles separated from mice ovaries differed between follicles. After 4 days of culture, the size of some secondary follicles was markedly increased, while that of others had either slightly increased, remained unchanged or shrunk. We compared the expression levels of growth factors between these secondary follicles and found that the growth rate of cultured secondary follicles correlated with the expression level of insulin-like growth factor 1 (Igf1) mRNA. Igf1 mRNA expression level in secondary follicles containing theca cells was higher than that in secondary follicles without theca cells, and the granulosa cell proliferation around follicles containing theca cells was increased. Furthermore, an IGF1 inhibitor also inhibited the granulosa cell proliferation, and administration of IGF1 to secondary follicles without growth promoted granulosa cell proliferation. These results indicated that the theca cells of secondary follicles induced the expression of IGF1 and promoted the follicle growth.  相似文献   
57.
pp. 865–874
Occurrence and survival of fecal-contamination indicator bacteria (coliform bacteria, Escherichia coli and Salmonella ) in various manure and compost samples collected from 23 composting facilities mostly in Kyushu were investigated by using selective media. Coliform bacteria were detected on desoxycholate agar from 11 (38%) of 29 product samples (15 cow dung manure, 4 poultry manure, 2 biosolid compost and 8 food waste compost) at a range of 102 to 106 cfu g1 dry matter. From positive samples, 21 isolates of possible coliform bacteria were purified. Among them, species of coliform bacteria ( E. coli , E. vulneria , Pantoea sp. and Buttiauxella agrestis ) were identified whereas isolates of Serratia marcescens , not coliform bacteria, were also obtained, suggesting that careful observation was necessary to avoid false positive counting due to the presence of a red colony of S. marcescens that resembled coliform bacteria. Isolates of E. coli were tested for slide aggregation with a set of antiserum against pathogenic E. coli serotypes and negative reaction was obtained for all the isolates tested. Direct detection of E. coli on Chromocult coliform agar and Salmonella on MLCB agar resulted in none and 2 (17%) of 12 samples tested, respectively. The fate of fecal-contamination indicator bacteria as above was followed during compost production on 7 cases at 6 compost facilities and 4 patterns were observed: fecal-contamination indicator bacteria 1) decreased and finally disappeared, 2) decreased once but re-growth was occurred on products, 3) decreased to some extent but remained in products, 4) was not detected throughout production. These results suggest that some fecal-contamination indicator bacteria may survive compost production and appropriate temperature control would be significant for hygiene control of manure and compost.  相似文献   
58.
Maize (Zea mays L.) cv. T42 was grown in refined sand at low (0.1 μM) and normal (30 μu) concentrations of boron each under low (1 mM), normal (4 mM), and excess (8 mM) supply of calcium. Visible symptoms of boron deficiency which appeared first, were accentuated by calcium deficiency and were least evident when calcium was added in excess. The yield was maximum at normal levels of boron and calcium and was the lowest under boron and calcium deficiency.

In maize leaves when both calcium and boron were deficient together the activity of starch phosphorylase increased markedly and that of ribonuclease and polyphenol oxidase also increased. The increase in the calcium content inhibited the starch phosphorylase activity when boron was deficient. The activity of peroxidase was stimulated under boron deficiency at all levels of calcium and that of ATPase was depressed significantly when calcium was deficient alone.

A decrease in the tissue boron (except in old leaves) and tissue calcium content as well as sugar and starch contents was observed under the combined deficiency of calcium and boron.

Excess calcium at both levels of boron increased the tissue boron and calcium contents and decreased the concentration of starch, sugars, nucleic acids, total and inorganic phosphorus, and the activities of starch phosphorylase and ATPase.

The activity of ATPase increased upon the addition of calcium to plants deficient in calcium and boron respectively. The tissue concentration of the element added increased when the element was applied to calcium or boron deficient maize plants.  相似文献   
59.
Protected areas are an appropriate means for managing biodiversity and have become increasingly central to conservation strategies. However, declaring a natural resource to be protected has an immense influence on the livelihoods of many local communities living in and around the protected area. This article explores the role of protected sal forests—namely, the Madhupur National Park (MNP) on the livelihoods of forest-dependent ethnic minorities, drawing empirical data from ethnic households. The results revealed that the MNP has brought changes, most of which have had negative impacts on ethnic livelihoods. Now their livelihoods are not stable, as most do not have substantial sources of securing income. In spite of this, the ethnic communities have experienced severe antagonistic relationships with park managers and faced social inequity; all these factors affect their livelihoods. Therefore, establishment of a legitimate process to constructively work with the local communities is the most feasible and just way to achieve conservation and development.  相似文献   
60.
An 8-year-old female Persian cat was brought in for evaluation of chronic vomiting. The presence of opaque enteric foreign bodies and intestinal obstruction along with azotaemia, hyperphosphataemia, moderate anaemia and peritoneal fluid were revealed following appropriate diagnostic work-up. Exploratory laparotomy confirmed jejunoileal dilation, ileocaecal stenosis, and numerous foreign objects in the jejunoileum. These foreign objects and ileocaecal stenosis were surgically removed, and intestinal resection and anastomosis was performed. The patient recovered favourably. Analysis revealed that the foreign objects were composed of calcium phosphate and calcium carbonate. Intestinal inflammation and stenosis secondary to enterolithiasis may have developed following ingestion of cat litter or a previous unrelated surgical intervention. We were unable to delineate the inciting pathogenesis in this particular case.  相似文献   
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