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1.
Summary Nitrate reductase (EC 1.6.6.2) activity (NRA), as measured by an in vivo assay, is present in needle leaves and mycorrhizal fine root tips of adult Norway spruce [Picea abies (L.) Karst.] in at least equal amounts on a fresh weight basis, in both adult and 5-year-old trees. NRA could also be demonstrated in trunk wood of deroted trees after fertilization with 5 mM , exhibiting a longitudinal profile in the trunk. Inducibility in needles can more efficiently be achieved by NO2 (100 g·m-3) than by 5 mM nitrate, which is effective only in root-amputated trees. A remarkably high level of needle-NRA in unfertilized trees, which are characterized by a very low level of nitrate in the xylem sap, suggests that NRA in spruce needles may in part be constitutive. Organic-N is a major nitrogen source for the needles even in root-amputated trees, indicating pronounced exchange processes between ray parenchyma and trunk xylem, which in turn are modified by the nitrogen source fed to the trunk stump. Intact trees exhibit a very similar amino acid composition of the xylem sap, regardless of whether or has been fed. The amino acid pattern of the needles is not thrown out of balance by flooding with and , which occurs in fertilized derooted trees. This indicates a distinct potential for homoeostasis of nitrogen entrance-metabolism (i.e. NRA and glutamine synthetase activity) in the needles. In the ectomycorrhiza/fine root-system (EMC), marked differences in NRA were observed depending on root-tip diameter and along the longitudinal profile of the fine roots. EMC-nitrate reductase is strongly enhanced by . Needle-NRA exhibits a circannual rhythm. An early summer maximum is followed by a December minimum. This activity pattern matches well the transitory increase of soluble nitrogen in spring and the total protein maximum in winter. In an indirect way assimilatory NRA may well contribute to nitrogen overfertilization (by consumption of NOX) as one possible cause of the contemporary decline of spruce populations.  相似文献   
2.
摘要 目的:评价放散式体外冲击波(rESW)穴位治疗联合中药熏洗在老年膝骨关节炎(KOA)中的应用效果。方法:选入2021年2月~2022年8月我院收治的老年KOA患者76例,根据治疗方法不同分为对照组和观察组,各38例,两组均予以中药熏洗,观察组加用rESW穴位治疗。评价两组的治疗效果、膝关节功能、疼痛程度等指标,并进行统计比较。结果:与治疗前相比,两组治疗2周、治疗4周时的VAS评分明显下降(P<0.05),而观察组下降幅度更大,与对照组差异显著(P<0.05);两组治疗前Lysholm评分无明显差异(P>0.05),而观察组治疗2周、治疗4周时的Lysholm评分显著高于对照组(P<0.05);观察组治疗显效率和有效率均显著高于对照组(P<0.05);观察组治疗2周、4周时的血清IL-1β、TNF-α和MMP-13水平较对照组低(P<0.05)。结论:rESW穴位联合中药熏洗治疗老年KOA患者疗效显著,可缓解疼痛症状,改善膝关节功能,控制炎症反应,且操作简单,值得推荐。  相似文献   
3.
Summary Soil and wheat bromide dynamics are studied in methyl bromide-fumigated plots in a Mediterranean climate. Bromide residues range between 5 to 10 ppm in the fumigated soil and they are distributed to a depth of 50–60 cm, where a compacted layer exists, in accordance with soil organic matter and moisture distribution. The total amount of bromide in soil is 5.8 gm−2 up to a depth of 1 m and it remains almost constant during the wheat growth period. The plant bromide concentration decreases throughout the development of spring wheat. The bromide distribution in the different plant organs was identical in the two years studied and it is correlated with the chloride content. Fumigation increases the phosphorus concentration in wheat and does not affect sulphur and chloride. Though the bromide concentration in the fumigated soils is high, the levels in the plants growing in it do not cause scorched areas. This may be due to antagonic Br/Cl and Br/NO3 effects.  相似文献   
4.
Myzus persicae (M. persicae) is now considered a threat to agricultural crops due to economic losses. Numerous synthetic insecticides applied every year against M. persicae, are reported to be unsafe for environment, humans, and beneficial insects. Furthermore, several species of Myzus have been found to develop resistance due to over application of these insecticides. Therefore, it is required to find some novel insecticide that would be safe for the environment as well as for humans. In the current study, two major pure constituents α-pinene and β-caryophyllene were evaluated for their insecticidal potential against M. persicae using a fumigant toxicity assay. Furthermore, impact of α-pinene and β-caryophyllene on expression of five different genes, e.g., HSP 60, FPPS I, OSD, TOL and ANT responsible for reproduction, dispersion, and growth of M. persicae has also been investigated. To perform fumigant toxicity assay, five different concentrations (3.5, 4, 4.5, 5 and 6 μL L−1) of α-pinene and β-caryophyllene were prepared. Lethal concentration (LC) was calculated, and gene expression studies were executed through qRT PCR at LC30 of α-pinene and β-caryophyllene. Both constituents demonstrated excellent fumigant toxicity effects against M. persicae at all five concentrations. However, α-pinene shows significantly better results (98%) as compared to β-caryophyllene (80%) after 72 h at 6 μL L−1 of dose. The highest upregulation in expression was demonstrated at LC30 dose of α-pinene in five in three out of five genes understudy (TOL, ANT, and FPPS I). Conversely, two genes HSP 60 and OSD demonstrated downregulation at LC30 dose of β-caryophyllene. Conclusively, our results highlighted the promising insecticidal potential of both compounds α-pinene and β-caryophylleneby interfering with the reproduction and development related processes in M. persicae, allowing us to recommend the phytoconstituents under investigation as an ecofriendly alternative to synthetic insecticides.  相似文献   
5.
目的:探讨中药熏蒸对经挂线引流术后肛瘘患者血清免疫球蛋白水平及预后的影响。方法:收集我院治疗的94例肛瘘患者,随机分为实验组和对照组,每组47例。所有患者行肛瘘挂线术,对照组患者术后采用左氧氟沙星注射液治疗,实验组患者在对照组基础上给予中药熏洗治疗。观察并比较两组患者治疗前后血清IgA及IgG水平,疼痛持续时间及恢复时间以及临床疗效。结果:与治疗前相比,两组患者治疗后血清IgA及IgG水平均下降,差异具有统计学意义(P0.05);与对照组相比,实验组患者治疗后血清IgA及IgG水平较低,差异具有统计学意义(P0.05);实验组患者疼痛持续时间及恢复时间均少于对照组,差异具有统计学意义(P0.05);实验组临床治疗有效率高于对照组,差异具有统计学意义(P0.05)。结论:中药熏蒸能够降低经挂线引流术后肛瘘患者血清IgA及IgG水平,缩短术后疼痛时间,促进术后康复,临床疗效较好。  相似文献   
6.
7.
The nematodes, Pratylenchus brachyurus, Trichodorus christiei, and T. porosus and the soil-borne fungi, Rhizoctonia solani, Pythium debaryanum, P. irregulare, P. ultimum, and Fusarium spp. were the pathogens most frequently found in the roots and rhizosphere of field-grown cotton (Gossypium hirsutum) showing "stunt" symptoms. Field-plot application of the nematicide D-D (l,2-dichloropropane, 1,3-dichloropropene) at 373.4 liter/ha (40 gal/A) significantly increased plant growth and yield. A fungicidal mixture of Dexon (p-dimethylaminobenzenediazo sodium sulfonate at 23.5 kg/ha (2l lb/A) and Terraclor (pentachloronitrobenzene at 25.2 kg/ha (22.5 lb/A) was phytotoxic, but combined nematicide/fungicide treatments were not. Greenhouse temperature-tank experiments in soils from two locations showed significantly improved root and shoot growth following methyl bromide fumigation at both 25 C and 18 C and more severe "stunt" at the lower temperature.  相似文献   
8.
The analogues carbon dioxide (CO(2)), carbonyl sulfide (COS) and carbon disulfide (CS(2)) have been useful as substrate probes for enzyme activities. Here we explored the affinity of the enzyme carbonic anhydrase for its natural substrate CO(2), as well as COS and CS(2) (1) by in vitro kinetic metabolism studies using pure enzyme and (2) through mortality bioassay of insects exposed to toxic levels of each of the gases during carbonic anhydrase inhibition. Hydrolysis of COS to form hydrogen sulfide was catalysed rapidly showing parameters K(m) 1.86 mM and K(cat) 41 s(-1) at 25 degrees C; however, the specificity constant (K(cat)/K(m)) was 4000-fold lower than the reported value for carbonic anhydrase-catalysed hydration of CO(2). Carbonic anhydrase-mediated CS(2) metabolism was a further 65,000-fold lower than COS. Both results demonstrate the deactivating effect toward the enzyme of sulfur substitution for oxygen in the molecule. We also investigated the role of carbonic anhydrases in CO(2), COS and CS(2) toxicity using a specific inhibitor, acetazolamide, administered to Tribolium castaneum (Herbst) larvae via the diet. CO(2) toxicity was greatly enhanced by up to seven-fold in acetazolamide-treated larvae indicating that carbonic anhydrases are a key protective enzyme in elevated CO(2) concentrations. Conversely, mortality was reduced by up to 12-fold in acetazolamide-treated larvae exposed to COS due to reduced formation of toxic hydrogen sulfide. CS(2) toxicity was unaffected by acetazolamide. These results show that carbonic anhydrase has a key role in toxicity of the substrates CO(2) and COS but not CS(2), despite minor differences in chemical formulae.  相似文献   
9.
目的:探讨中药熏洗在肛瘘患者经挂线引流术后的临床应用效果。方法:收集我院收治的70例肛瘘挂线引流术后患者,随机分为实验组和对照组,每组35例,患者均行肛瘘经挂线引流术,术后对照组给予常规护理治疗,实验组患者给予自拟熏洗方进行中药熏洗。治疗结束后,比较两组患者的疼痛持续时间、恢复时间、创面愈合速度、症状评分并发症发生率以及复发率。结果:与治疗前相比,两组患者治疗后的症状评分均显著下降(P0.05),而实验组患者治疗后的症状评分、疼痛持续时间、恢复时间、并发症发生率以及复发率明显低于对照组(P0.05),创面愈合速度显著快于对照组(P0.05)。结论:中药熏洗能够有效促进肛瘘患者经挂线引流术后恢复并减少复发,且安全性较高。  相似文献   
10.
杨帆  刘孝兵  李峰  张雪  宋印娥 《生物磁学》2014,(9):1744-1746
目的:分析复方甘草酸苷联合中药熏蒸及窄谱紫外线治疗银屑病的临床治疗效果。方法:观察组患者给予复方甘草酸苷联合中药熏蒸及窄谱紫外线治疗,对照组患者给予复方甘草酸苷治疗。观察比较两组患者的治疗效果。结果:观察组患者治疗后PASI评分为(4.0±2.1)分明显低于对照组的(7.6±2.4)分,两组比较差异具有统计学意义(P〈0.05);观察组的复发率为17.7%明显低于对照组的45.2%,两组比较差异具有统计学意义(P〈0.05);观察组的总有效率为88.71%,明显高于对照组的74.19%,两组比较具有显著性差异(P〈0.05)。结论:复方甘草酸苷联合中药熏蒸及窄谱紫外线用于治疗银屑病,临床效果显著,值得在临床上推广应用。  相似文献   
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