首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   473篇
  免费   20篇
  国内免费   1篇
林业   76篇
农学   14篇
  62篇
综合类   30篇
农作物   7篇
水产渔业   46篇
畜牧兽医   230篇
园艺   1篇
植物保护   28篇
  2023年   1篇
  2022年   3篇
  2021年   13篇
  2020年   10篇
  2019年   16篇
  2018年   10篇
  2017年   11篇
  2016年   13篇
  2015年   11篇
  2014年   18篇
  2013年   39篇
  2012年   29篇
  2011年   35篇
  2010年   16篇
  2009年   21篇
  2008年   30篇
  2007年   39篇
  2006年   28篇
  2005年   37篇
  2004年   33篇
  2003年   20篇
  2002年   17篇
  2001年   10篇
  2000年   5篇
  1999年   5篇
  1998年   1篇
  1997年   2篇
  1996年   3篇
  1993年   1篇
  1990年   2篇
  1989年   1篇
  1988年   2篇
  1987年   2篇
  1986年   1篇
  1985年   1篇
  1984年   3篇
  1983年   1篇
  1982年   1篇
  1973年   2篇
  1966年   1篇
排序方式: 共有494条查询结果,搜索用时 609 毫秒
1.
Atopic dermatitis (AD) is thought to be caused by immunologic abnormalities expressed as a Th1/Th2 cytokine imbalance in both humans and dogs. Several studies have focused on the therapeutic effects of IFNγ in human AD with successful results; however, the mechanism of action of IFNγ is not fully understood. We investigated the effect of recombinant canine interferon gamma (rCaIFNγ) on 10 dogs with AD and evaluated the ratio of IL‐4 mRNA to IFNγ mRNA in peripheral blood mononuclear cells, serum total IgE levels, and histological changes in skin. After six injections of rCaIFNγ over a span of 2 weeks, seven of the 10 dogs showed improvement, and six of these seven dogs exhibited decreased IL‐4:IFNγ mRNA ratios. Two of the three cases that did not improve had increased IL‐4:IFNγ mRNA ratios. Total serum IgE levels were significantly decreased in nine of 10 cases. The number of IgE‐positive cells detected by immunostaining and the number of mast cells in skin biopsy samples were decreased. A reduction of epidermal cell layers was demonstrated by histopathology after treatment. These results demonstrated that rCaIFNγ may be a novel safe and effective therapeutic option for the treatment of canine AD, and the mechanism of action of rCaIFNγ may be related to the modulation of Th2 cytokines to Th1 cytokines with the reduction of serum IgE production. Funding: Self‐funded.  相似文献   
2.
The usefulness of the intradermal test (IDT) and the serological allergy test (SAT) for detecting antigen‐specific IgE in allergic cats has not yet been established. In this study, we compared the results of IDT with those of SAT and evaluated the clinical usefulness of the two tests for detecting possible allergens in allergic cats. IDT and SAT using eight antigens were performed on 22 cats with intense pruritus after excluding ectoparasites and performing diet elimination tests. Approximately 50% of the cats reacted to at least one allergen by either IDT or SAT, and 36.4% of the cats reacted on both IDT and SAT. In contrast, seven healthy cats did not show any reactions on IDT or SAT. The most commonly detected allergen in both tests was house dust mites (IDT, 36.4%; SAT, 40.9%). Five cats reacted to one allergen and the others reacted to more than one allergen with IDT. Three cats reacted to one allergen with SAT. The following percentage agreement between the results of the two tests was calculated: house dust mites (86.4%), cat fleas (63.6%), grass mix (86.4%), common mugwort (81.8%), cat epithelia (90.9%), ragweed (86.4%), Japanese cedar (90.9%), and plantain (81.8%). The overall mean percentage agreement was 83.5%. In summary, the present study showed good agreement between IDT and SAT for cats, and SAT may be more sensitive than IDT, but less specific for detecting sensitized allergens. Funding: Self‐funded.  相似文献   
3.
The effects of the calcineurin inhibitors cyclosporine A (CsA) and FK506 on the mRNA expressions of various cytokines were evaluated in dogs to determine whether the effects of CsA and FK506 in dogs were similar to those in humans. The mRNA expression levels of the cytokines IL-2, IL-4, IFN-gamma and TNF-alpha were measured in PHA-stimulated canine PBMC using real-time RT-PCR after incubation with CsA or FK506 for 5 hr. Both reagents inhibited IL-2, IL-4 and IFN-gamma mRNA expressions in a dose-dependent manner. However, CsA hardly inhibited the mRNA expression of TNF-alpha. These findings are important for assessing the indications of CsA treatment in dogs.  相似文献   
4.
5.
A 3.5-year-old, male West Highland White Terrier was diagnosed as having hyperplastic dermatosis by clinical and histopathological findings. Controlling of Malassezia overgrowth by antifungal drugs provided a temporal improvement of the skin lesions, but the disease was deteriorated within the next 2 months despite the negative demonstration of the yeasts. Induction of recombinant canine interferon-gamma (rCaIFN-gamma) therapy resulted in almost complete cure of the skin lesions within 2 months after the initiation of the therapy. No adverse effects were detected during the therapy. Our results suggested that the rCaIFN-gamma therapy is potential to be a novel therapeutic option for controlling the breed-specific hyperplastic skin disease.  相似文献   
6.
This study was designed to develop a novel culture method for the efficient proliferation of canine peripheral blood lymphocytes (cPBL) for adoptive immunotherapy. When cPBL were cultured in the presence of concanavalin A (Con A), proliferation of cPBL was induced and expression of interleukin-2 receptor (IL-2R) which enables to respond to exogenously added IL-2 was upregulated. And then, when cPBL were cultured with recombinant human interleukin-2 (rhIL-2) in addition to Con A, proliferation was accelerated and increased to about 10-fold after 1 week. The phenotypic analysis showed that the main population of the cultured cPBL was consisted of CD8+ positive lymphocytes. Among them, CD4+CD8+ double positive (DP) lymphocytes had significantly increased, and the ratio of CD4+ single positive (SP) lymphocytes to CD8+ SP lymphocytes (CD4+SP/CD8+SP) was decreased as compared to before culturing. To evaluate the cytotoxic activity of cPBL cultured with Con A and rhIL-2, furthermore, cytotoxic assay was carried out against xenogeneic melanoma cell line (MeWo), which resulted in MHC-unrestricted cytokilling. These results suggest that the culture method of cPBL by the use of Con A and rhIL-2 may be useful for generating lymphokine activated killer cells, and also this may be beneficial for adoptive immunotherapy of tumor-bearing dogs.  相似文献   
7.
8.
Abstract

In alkaline soils, plant growth is impaired mainly by high pH and high concentration of bicarbonates. The bicarbonate concentration increases the pH value, and causes deficiency of iron. A bicarbonate-resistant cell line (BR line) of tobacco (Nicotiana tabacum L. cv. Burley21) was selected by adding excess bicarbonate ions (20 mmol L?1) to the culture medium. The pH of the medium was buffered 8.0 to 8.3. Under these conditions, about 80% of iron in the medium became insoluble. However, under such conditions, the BR line grew well. In this report, we examined some characteristics of the growth and iron uptake in the BR line under iron-deficient (i.e. high pH or no-iron) condition. At pH 5.8, the Fe3+ reduction activity was not significantly different between the non-selected line and the BR line. At pH 8.0, however, the Fe3+ reduction activity of the BR line was higher than that of the non-selected line. In no-iron condition, the growth of the non-selected line was markedly reduced after 2 weeks, while the BR line was not affected. The content of malic acid in both lines increased with the medium pH, and the content in the BR line was higher than that in the non-selected line. The BR line was able to adapt to the conditions, which restricted iron uptake, such as high bicarbonate concentration, high pH, and low iron conditions. The high ability of Fe3+ reduction was maintained at even high pH conditions. Further, the BR line may be able to improve the utilization of iron in the cells.  相似文献   
9.
Coat protein sequences of two isolates in strain A2 and five isolates in strain D of Soybean mosaic virus (SMV), which caused a recent mosaic outbreak in soybeans (cv. Sachiyutaka) in Chugoku and Shikoku in Japan, were compared to published data on 15 other Asian-origin isolates. Sequence comparison and cluster analysis showed that SMV isolates of strain A2 from these districts were closely related, as were those of strain D, but strains A2 and D were not. Thus, the two strains may have different origins and be carried through seed transmission.  相似文献   
10.
Dendritic cells (DCs) are the most potent antigen-presenting cells that are expected to be therapeutic agents for tumor immunotherapy. In this study, we generated DCs of sufficient number for DC-based immunotherapy from peripheral blood mononuclear cells (PBMC) in dogs. PBMC were cultured in the presence of phytohemagglutinin (PHA). On day 6, large adherent cells with dendrite-like projections were seen, and the number of these large cells with projections increased on day 8. These cells were positive for esterase staining. They expressed MHC class II, CD11b, CD8 and weakly CD4 on their surface. They tended to make contact with lymphocytes under culture conditions. We obtained about 2-5 x 10(6) of DCs from 10 ml of peripheral blood. These DCs phagocytosed HEK-293 cells by overnight co-culturing. These cells generated from PBMC are possible canine DCs and are applicable to clinical trials of DC-based whole tumor cell immunotherapy in dogs.  相似文献   
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号