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柚木为马鞭草科柚木属植物,是世界上最珍贵的用材树种之一。文章介绍了柚木的生物学特性、无性繁殖即组培技术要点以及造林技术,论述了柚木在我省的推广前景。 相似文献
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Christopher L. Mariani DVM Simon R. Platt BVMS MRCVS Susan M. Newell DVM MS Scott P. Terrell DVM Cheryl L. Chrisman DVM MS EDS Roger M. Clemmons DVM PhD 《Veterinary radiology & ultrasound》2001,42(6):524-531
A 3-year-old neutered female mixed breed dog was examined because of severe, generalized seizure activity, tetraparesis, and encephalopathic signs. Cerebrospinal fluid (CSF) evaluation was unremarkable except for a mild increase in protein. Serum and CSF titers for infectious diseases were negative. Magnetic resonance (MR) imaging examination of the brain was performed and lesions were found within the cerebral gray matter of the temporal and parietal lobes. The lesions had increased signal intensity on T1, T2, and proton density-weighted images. There was mild inhomogeneous enhancement following intravenous contrast medium administration. Neurologic status improved and the seizures were well controlled, but the dog never regained normal mentation and euthanasia was performed 10 weeks after initial evaluation. At necropsy, severe cerebral cortical necrosis was found in the regions corresponding to the lesions seen on MR imaging examination. Large numbers of fat-containing macrophages (gitter cells) were found within these areas, and are thought to be responsible for the characteristic hyperintensity seen on the MR images. 相似文献
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CTGF, a member of the CCN family of immediate early genes, is a recently discovered profibrotic growth factor, which is involved in many pathophysiologic procedures. CTGF acts as a downstream effector of TGF-β acting on interstitial cells to enhance the progression of fibrotic renal diseases. It has been shown that CTGF gene expression can be induced or blocked by some kinds of cytokine and drugs. It is an interesting candidate target for future intervention strategies of renal interstitial fibrosis. 相似文献
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贮藏期间福桔果皮细胞始终具有分裂增殖能力,细胞生长的养分主要通过维管束向果肉吸取,因而促进果肉衰老,形成枯水.枯水果实在贮藏早期就发现果皮细胞层和油腔分泌细胞无丝分裂旺盛,双核细胞多,果皮增厚多.严重枯水时,果皮细胞还具细胞核、线粒体、有色体等超微结构,未枯水果实细胞分裂少见.经预贮后贮藏的果实,由于中断了果皮组织与维管束的联系,果皮细胞生长受抑制,果肉水分、养分消耗少,枯水率最低, 相似文献
7.
Acquired resistance triggered by elicitins in tobacco and other plants 总被引:17,自引:0,他引:17
Philippe Bonnet Eva Bourdon Michel Ponchet Jean -Pierre Blein Pierre Ricci 《European journal of plant pathology / European Foundation for Plant Pathology》1996,102(2):181-192
Elicitins are a family of proteins excreted byPhytophthora spp. They exhibit high sequence homology but large net charge differences. They induce necrosis in tobacco plants which then become resistant to the tobacco pathogenPhytophthora parasitica var.nicotianae. In stem-treated plants, resistance was not restricted to the site of elicitin application, but could be demonstrated by petiole inoculation at all levels on the stem. Resistance was already maximum after two days and lasted for at least two weeks. It was effective not only towardsP. p. var.nicotianae infection, but also against the unrelated pathogenSclerotinia sclerotiorum. In contrast to dichloroisonicotinic acid, an artificial inducer of systemic acquired resistance, which was increasingly effective with doses ranging from 0.25 to 5mole per plant, the basic elicitin cryptogein exhibited a threshold effect, inducing near total resistance and extensive leaf necrosis above 0.1 nmole per plant. Between 1 and 5 nmole, acidic elicitins (capsicein and parasiticein) protected tobacco plants with hardly any necrotic symptom. Elicitins exhibited similar effects in various tobacco cultivars andNicotiana species, although with quantitative differences, but induced neither necrosis nor protection in other SolanaceÆ (tomato, petunia and pepper). Among 24 additional species tested belonging to 18 botanical families, only some BrassicaceÆ, noticeably rape, exhibited symptoms in response to elicitins, in a cultivar-specific manner. Elicitins appear to be natural specific triggers for systemic acquired resistance and provide a tool for unraveling the mechanisms leading to its establishment.Abbreviations AR
acquired resistance
- HR
hypersensitive response
- INA
2,6-dichloroisonicotinic acid
- Ppn
Phytophthora parasitica var.nicotianae
- SAR
systemic acquired resistance 相似文献
8.
J. Rashid D. J. Weiss S. K. Maheswaran M. P. Murtaugh 《Veterinary research communications》1996,20(6):519-531
Local and systemic activation of coagulation is frequently associated with bacterial sepsis. The coagulopathy is due, at least in part, to expression of tissue factor (TF) by monocytes and macrophages. The purpose of this study was to evaluate the expression of procoagulant activity by bovine alveolar macrophages, leukocytes and platelets, and to determine the relative potency of three chemical inhibitors of TF expression (pentoxifylline, retinoic acid, and cyclosporin A). Bovine alveolar macrophages were stimulated with lipopolysaccharide (LPS) derived from Pasteurella haemolytica or recombinant bovine tumour nervous factor (TNF) and dose- and time-dependent effects on TF expression were studied. LPS and TNF induced TF expression in alveolar macrophages and LPS treatment of whole blood induced TF expression in mononuclear cells. Neutrophils and platelets also expressed procoagulant activity, but this activity was not inhibited by anti-bovine TF monoclonal antibody. Pentoxifylline (40 mol/L), retinoic acid (0.01 mmol/L) and cyclosporin A (0.08 mol/L) inhibited TF expression when added concurrently with LPS or TNF, but not when added 4 h after stimulation. TF mRNA was not detected in unstimulated alveolar macrophages by Northern blot analysis. In contrast, exposure to LPS or TNF for 6 h induced marked expression of TF mRNA, which was inhibited by treatment with pentoxifylline, retinoic acid and cyclosporin A. Expression of TNF by alveolar macrophages stimulated with LPS was also inhibited by these compounds. Our results indicate that procoagulant activity expressed by alveolar macrophages and monocytes is associated with expression of TF, whereas procoagulant activity expressed by neutrophils and platelets is not. The concentrations of pentoxifylline and retinoic acid necessary for inhibition of TF expression in vitro may not be achievable in vivo owing to their toxic effects. However, the in vitro concentration of cyclosporin A that inhibited TF expression did not exceed the plasma concentration observed in humans, and therefore may be useful for inhibition of TF expression in vivo.Abbreviations BAL
bronchoalveolar lavage
- LPS
lipopolysaccharide
- cDNA
cloned deoxyribonucleic acid
- cAMP
cyclic adenosine monophosphate
- GAPDH
glyceraldehyde phosphate dehydrogenase
- mRNA
messenger ribonucleic acid
- TF
tissue factor
- TNF
tumour necrosis factor
- DPBS
Dulbecco's phosphate-buffered saline 相似文献
9.
Pathogenic mechanisms of caprine arthritis-encephalitis virus 总被引:1,自引:0,他引:1
E. G. Mdurvwa P. O. Ogunbiyi H. S. Gakou P. G. Reddy 《Veterinary research communications》1994,18(6):483-490
Goats infected with caprine arthritis-encephalitis virus (CAEV) show chronic arthritis and cachexia, which are progressive in nature. The immunopathogenic mechanisms responsible for these progressive clinical symptoms have not been fully elucidated. Various haematological and immunological parameters were evaluated in experimentally-infected goats showing typical signs of CAEV-induced disease. Infected goats showed recurrent lymphocytosis that may be due to constant presentation of antigen by infected cells of a monocyte/macrophage lineage. The serum alkaline phosphatase and -glutamyl transferase concentrations were elevated in infected goats, a characteristic of hepatic and bone disorders. All other serum chemistry parameters were similar between infected and control goats. Importantly, the serum tumour necrosis factor- (TNF-) levels were higher in infected goats. The cachexia seen in infected goats may be at least partly due to altered metabolism as a result of prolonged elevation of serum TNF- levels. Depressed natural killer cell activity was observed in infected goats and may contribute towards the establishment of a persistent infection with CAEV.Abbreviations AIDS
acquired immunodeficiency syndrome
- CAEV
caprine arthritis-encephalitis virus
- GGT
-glutamyl transferase
- HBSS
Hanks' balanced salt solution
- HIV
human immunodeficiency virus
- NK
natural killer
- PBMC
peripheral blood mononuclear cells
- PCR
polymerase chain reaction
- SAP
serum alkaline phosphatase
- TNF
tumour necrosis factor 相似文献
10.
I. Bouwen D. Z. Maat 《European journal of plant pathology / European Foundation for Plant Pathology》1992,98(2):141-156
Two viruses, detected frequently in the Netherlands in pelargonium, were identified by serology and test plant reactions. Antisera were prepared and an ELISA procedure was developed to detect the viruses in pelargonium.One of the viruses, PFBV-N, proved to be pelargonium flower-break virus. With the antiserum to PFBV-N, it could be detected reliably throughout the year inPelargonium zonale Springtime Irene.The other virus, PLPV-N, was serologically closely related to pelargonium line pattern virus (PLPV) and to pelargonium ring pattern virus (PRPV), as were an old virus isolate from Saturnus, collected in the Netherlands in 1971 (L128), and PLPV isolates from Yugoslavia (PLPV-Y) and Denmark (PLPV-D). There were only minor differences in host-plant reactions between the virus isolates. Based on these tests, PLPV and PRPV are considered as isolates of the same virus, for which, for practical reasons, the name pelargonium line pattern virus is proposed.PLPV could be reliably detected by ELISA inP. zonale Springtime Irene and Amanda throughout the year with only a few exceptions. InPelargonium peltatum Tavira, however, reslts were erratic due to uneven distribution of virus in the plant. Best results were obtained when petioles of fully expanded leaves were tested. 相似文献