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111.
溴甲烷熏蒸马铃薯种薯防治块茎蛾的研究   总被引:2,自引:0,他引:2  
溴甲烷熏蒸馬鈴薯种薯防治块茎蛾研究結果:在温度10—15℃和15—20℃,药量每立方米35克;温度7—10℃,每立方米45克,密閉均为3小时,对蛹、幼虫、卵、成虫的死亡率均为100%。在温度20℃,药量每立方米45克,密閉5小时,在职上熏蒸因子幅度范围职内,相隔5天后播种,对出苗、生长和产量均无不夏影响。休眠、有芽或淋雨种薯熏蒸后,其出苗、生长亦无显著差異。各虫态致死中率測定:以中期蛹耐药力最强,順序为卵、幼虫和成虫。中期蛹的药量,比卵高2倍,比幼虫高4倍左右,比成虫高8倍。成虫致死中率药量只需每升4毫克,与溴甲烷木箱熏蒸結果是相符合的。在大規模熏蒸示范中,得出一套仓庫熏蒸和帐幕熏蒸的操作經驗,可供生产上应用。  相似文献   
112.
The effect on spore germmation and germ tube growth of Diplodia pinea produced by (+)- α-pinene, (?)-β-pinene, (+)-Δ3-carene, (?)-limonene, β-phellandrene, and terpinolene was determined over a range of vapour concentrations. Spore germination was most inhibited by A3-carene; germ tube growth was inhibited by all these monoterpenes except (?)-limonenc and ß-phellandrene. In contrast to the low toxicity of (?)-limonene, (+)-limonene (not known to be present in Pinus radiata cortical oleoresin) was extremely toxic to both spore germination and germ tube growth. The results arc discussed in rotation to an earlier observation that trees free of dieback in the field had high levels of certain monoterpenes.  相似文献   
113.
Twelve clinically sound, healthy, athletically conditioned Thoroughbred horses were subjected to an incremental exercise stress test to determine the effects and period of detection of a single dose of flunixin meglumine (1.1 mg/kg by intravenous injection) in serum and urine by ELISA. Flunixin concentrations, performance, and hematologic and clinical chemical parameters were measured. All horses were rotated through four treatment groups of a Latin-square design providing for each horse to serve as its own control. Flunixin meglumine reduced prostaglandin F(1alpha) and thromboxane concentrations that had been increased by intense exercise. Performance parameters did not improve and prostaglandin concentrations did not significantly correlate with total run time. Exercise did not change the flunixin elimination profile in either serum or urine, and concentrations were found to be below the detection limit of the ELISA test within 36 hours in serum and 120 hours in urine.  相似文献   
114.
Overexpression of matrix metalloproteinases (MMPs) is a major pathological factor causing cartilage destruction in osteoarthritis (OA). This study aimed to investigate the effects and mechanisms of sesamol on expression of MMPs in activated chondrosarcoma cells. Sesamol significantly attenuated TNF-α- and IL-1β-induced gelatinolysis and expression of MMP-9 in a concentration-dependent manner in SW1353 cells. Additionally, both MMP-1 and -13 stimulated by PMA were inhibited by sesamol. On the other hand, the NF-κB signaling activation through IκB-α degradation was restored by sesamol under TNF-α or PMA stimulation. Furthermore, this bioactive compound exerted the reduction on phosphorylation of ERK1/2 or p38 MAPKs after either PMA or IL-1β stimulation. This study also evaluated whether sesamol down-regulates MMP expression in the joint cartilage of monosodium iodoacetate (MIA)-induced OA in rats. Sesamol prevented the expression of MMP-1 and -9 in the cartilage of MIA-induced OA in rats. The results of this study demonstrate that sesamol inhibits cytokine- or PMA-induced MMPs expression through the signal pathways of either NF-κB or ERK/p38 MAPKs down-regulation. This study also showed that sesamol attenuates destructive factor expression in vivo, providing a potential strategy for the chondroprotective therapy in OA.  相似文献   
115.
Pycnogenol, polyphenolic compounds extracted from the pine bark, is beneficial for human health. To understand more of its effects, the present study is to explore the protein expression pattern induced by pycnogenol in RAW 264.7 cells. Global analysis using two-dimensional gel electrophoresis indicated that treatment with pycnogenol induces upregulation of four proteins, whose identities were revealed by mass spectrometry as cathepsin D, keratinocyte lipid-binding protein, proteasome subunit alpha type 1, and annexin IV. The pycnogenol effect displayed a time- and concentration-dependent manner. Unlike pycnogenol, N-acetyl cysteine and vitamin C had no effect on cathepsin D expression. Further studies showed that cathepsin D induction is correlated with an increase of lysosomal staining and enhancement of phagocytosis. These results reveal the novel effects of pycnogenol on protein expression and phagocytic functions and illustrate the advantage of proteomics-based strategy in unveiling the molecular basis of phytochemicals.  相似文献   
116.
辽宁地区玉米螟化学防治的研究   总被引:2,自引:0,他引:2  
1958—1962年在辽宁省新金、辽中及沈阳三地,对为害玉米及谷子的玉米螟进行了化学防治試驗。試驗証明:玉米心叶末期或田間初見卵后20—25天,或田間第一代螟卵接近绝跡时均可作为辽宁地区进行化学防治适期的标准。用5%DDT或1%六六六顆粒剂适期施药,对第一代玉米螟都有100%效果。于玉米收获前剖查,經5%DDT与1%六六六顆粒剂处理后,減虫率分別为70%以上和60%以上。心叶期增加施药次数并不能增加防治效果。从顆粒剂的加工方法来看,混和顆粒剂优于拌粉顆粒剂。谷子上化学防治的适宜时期,为田间初見卵后15—20天,相当于第一代卵高峯或卵高峯后3—5天。用5%DDT、0.5%六六六1∶1混合粉剂,每亩4斤施于谷子茎基部,一次施药,可得70—80%以上的防治效果。  相似文献   
117.
Solanum nigrum L. (SN) has been used in traditional folk medicine to treat different cancers. It is also used as a hepatoprotective and anti-inflammatory agent. In this study, we demonstrated that the extract of SN (SNE) induced a strong cytotoxic effect toward HepG2 cells but much less to Chang liver and WRL-68 cells. The mechanisms of the cytotoxic effect were concentration-dependent. High doses of SNE (2 and 5 mg/mL) induced apoptotic cell death in HepG2 cells, as evidenced by increases in the expressions of p-JNK and Bax, mitochodrial release of cytochrome c, and caspase activation. On the other hand, cells treated with low concentrations of SNE (50-1000 microg/mL) revealed morphological and ultrastructural changes of autophagocytic death under electron microscopic observation. Furthermore, these cells showed increased levels of autophagic vacuoles and LC3-I and LC3-II proteins, specific markers of autophagy. The levels of Bcl-2 and Akt that have been implicated in the down-regulation of autophagy were decreased upon SNE treatment. Taken together, these findings indicate that SNE induced cell death in hepatoma cells via two distinct antineoplastic activities of SNE, the ability to induce apoptosis and autophagocytosis, therefore suggesting that it may provide leverage to treat liver cancer.  相似文献   
118.
119.
The ripe edible fruits of Psidium guajava L. was phytochemically investigated, three benzophenone glycosides, 2, 6-dihydroxy-3, 5-dimethyl-4-O-β-D-glucopyranosyl-benzophenone (1), 2, 6-dihydroxy-3-methyl-4-O-(6″-O-galloyl-β-D-glucopyranosyl)-benzophenone (2), 2, 6-dihydroxy-3, 5-dimethyl-4-O-(6″-O-galloyl-β-D-glucopyranosyl)-benzophenone (3) were isolated by means of chromatography, and their structures were elucidated on the basis of mass spectrometry, 1H NMR, 13C NMR, HSQC and HMBC data. Compounds 1 and 2 were new benzophenone glycosides, and here we report the complete spectroscopic assignments for 3.  相似文献   
120.
雪花梨贮藏中红肉病的研究   总被引:4,自引:1,他引:4  
  相似文献   
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