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101.
Limited data are available relating water potential () to crop residue water content (), although this relationship is important to study decomposition and moisture retention of the residue layer in no-till systems and other agricultural situations where residues are used. The objectives of this study were (i) to determine the characteristic moisture curves of rye (Secale cereale L.) and clover residues (Trifolium incarnatum L.), and (ii) to determine residue characteristics that can predict maximum water content of crop residues. Air-dried residues were separated into leaves and stems, cut into 0.5 cm length pieces and saturated with distilled water. Pieces of the drained residues were dried to various water contents in the laboratory and then transferred into thermocouple psychrometer chambers. Characteristic moisture functions of the type = a –b, where a and b are empirical constants, were fitted to the data. The characteristic moisture curves had a similar shape to that of a Cecil sandy loam soil used as an example; however, while plant residues were able to retain up to 4.3 g H2O g–1, the mineral soil retained only 0.22 g H2O g–1. Soluble carbohydrate concentration can be used as a practical index to estimate maximum water content of residues, given the good relationship between both variables (R
2 = 0.92). 相似文献
102.
Copper amine oxidase expression in defense responses to wounding and Ascochyta rabiei invasion 总被引:2,自引:0,他引:2 下载免费PDF全文
Wounding chickpea (Cicer arietinum) internodes or cotyledons resulted in an increase in the steady-state level of copper amine oxidase (CuAO) expression both locally and systemically. Dissection of the molecular mechanisms controlling CuAO expression indicated that jasmonic acid worked as a potent inducer of the basal and wound-inducible CuAO expression, whereas salicylic acid and abscisic acid caused a strong reduction of the wound-induced CuAO expression, without having any effect on the basal levels. Epicotyl treatment with the CuAO mechanism-based inhibitor 2-bromoethylamine decreased hydrogen peroxide (H(2)O(2)) levels in all the internodes, as evidenced in vivo by 3,3'-diaminobenzidine oxidation. Moreover, inhibitor pretreatment of wounded epicotyls resulted in a lower accumulation of H(2)O(2) both at the wound site and in distal organs. In vivo CuAO inhibition by 2-bromoethylamine after inoculation of resistant chickpea cv Sultano with Ascochyta rabiei resulted in the development of extended necrotic lesions, with extensive cell damage occurring in sclerenchyma and cortical parenchyma tissues. These results, besides stressing the fine-tuning by key signaling molecules in wound-induced CuAO regulation, demonstrate that local and systemic CuAO induction is essential for H(2)O(2) production in response to wounding and indicate the relevance of these enzymes in protection against pathogens. 相似文献
103.
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Isla MI Ordóñez RM Moreno MI Sampietro AR Vattuone MA 《Journal of enzyme inhibition and medicinal chemistry》2002,17(1):37-43
The invertase inhibitory protein isolated from Cyphomandra betacea Sendt and Solanum tuberosum inhibited the invertase activity from different species, genera and even plant family. Furthermore, proteinaceous inhibitors are not invertase specific; fungal, bacterial and higher plant enzymes including polygalacturonase, pectinase, pectin lyase, alpha-L-arabinofuranosidase and beta-glucosidase are also shown to be inhibited. Both inhibitors exhibited an in vitro antibacterial action against phytopathogenics strains of Xanthomonas campestris pvar vesicatoria CECT 792, Pseudomonas solanacearum CECT 125, Pseudomonas corrugata CECT 124, Pseudomonas syringae and Erwinia carotovora var carotovora. 相似文献
106.
A near infrared spectroscopic method was developed to determine drug content in a 20% (wt/wt) ibuprofen and spray-dried hydous
lactose blend. A blending profile was obtained after blending for 0.5, 1, 3, 5, 10, and 20 minutes. Stream sampling was used
to collect about 20 blend samples at each of the blending times from a laboratory scale V-blender. The samples collected were
used to develop a near infrared calibration model. The calibration model was then used to determine the drug content of unknown
samples from 2 validation blends. The validation blends were not included in the calibration model; they were used to evaluate
the effectiveness of the calibration model. A total of 45 samples from the 2 validation blends were predicted by the near
infrared calibration model and then analyzed by a validated UV spectrophotometric method. The root mean square error of prediction
for the first validation blend was 5.69 mg/g and 3.30 mg/g for the samples from the second blend. A paired t test at the 95%
confidence level did not indicate any differences between the drug content predicted by the near infrared spectroscopy (NIRS)
method and the validated UV method for the 2 blends. The results show that the NIRS method could be developed while the blending
profile is generated and used to thoroughly characterize a new formulation during development by analyzing a large number
of samples. The new formulation could be transferred to a manufacturing plant with an NIRS method to facilitate blend uniformity
analysis. 相似文献
107.
Image processing,diagnostic information extraction and quantitative assessment in pathology 总被引:1,自引:1,他引:0
Santinelli A Mazzucchelli R Colanzi P Tinca A Montironi R 《Journal of cellular and molecular medicine》2002,6(1):93-106
As we enter the information age we hold strong beliefs in the benefits of digital technology applied to pathology: numerical representation offers objectivity . Digital knowledge may indeed lead to significant information discovery, and, processing systems might be designed to allow a true evolution of capabilities. Questions arise whether the methodology underlying quantitative analysis provides the information that we need and whether it is appropriate for some of the problems encountered in diagnostic and prognostic histopathology. While one certainly would not dispute the value of statistical procedures, the clinical needs call for individual patient targeted prognosis. 相似文献
108.
109.
Maria Antonietta Stazi Rodolfo Cotichini Valeria Patriarca Sonia Brescianini Corrado Fagnani Cristina D'Ippolito Stefania Cannoni Giovanni Ristori Marco Salvetti 《Twin research》2002,5(5):382-386
The unique opportunity given by the "fiscal code", an alphanumeric identification with demographic information on any single person residing in Italy, introduced in 1976 by the Ministry of Finance, allowed a database of all potential Italian twins to be created. This database contains up to now name, surname, date and place of birth and home address of about 1,300,000 "possible twins". Even though we estimated an excess of 40% of pseudo-twins, this still is the world's largest twin population ever collected. The database of possible twins is currently used in population-based studies on multiple sclerosis, Alzheimer's disease, celiac disease, and type 1 diabetes. A system is currently being developed for linking the database with data from mortality and cancer registries. In 2001, the Italian Government, through the Ministry of Health, financed a broad national research program on twin studies, including the establishment of a national twin registry. Among all the possible twins, a sample of 500,000 individuals are going to be contacted and we expect to enrol around 120,000 real twin pairs in a formal Twin Registry. According to available financial resources, a sub sample of the enrolled population will be asked to donate DNA. A biological bank from twins will be then implemented, guaranteeing information on future etiological questions regarding genetic and modifiable factors for physical impairment and disability, cancers, cardiovascular diseases and other age related chronic illnesses. 相似文献
110.
Maleno I López-Nevot MA Cabrera T Salinero J Garrido F 《Cancer immunology, immunotherapy : CII》2002,51(7):389-396
Major histocompatibility complex (MHC) class I loss or downregulation in cancer cells is a major immune escape route used by a large variety of human tumors to evade anti-tumor immune responses mediated by cytotoxic T lymphocytes. Multiple mechanisms are responsible for such HLA class I alterations. However, the precise frequency of these molecular defects has not been clearly determined in tumors derived from specific tissues. To analyze such defects we aim to define the major HLA class I-altered phenotypes in different tumor types. In this paper we report on HLA class I expression in 70 laryngeal carcinomas. We used immunohistological techniques with a highly selective panel of anti-HLA monoclonal antibodies (mAb), and polymerase chain reaction (PCR) microsatellite amplification of previously selected microsatellite markers (STR) located in chromosome 6 and 15. DNA was obtained from microdissected tumor tissues and surrounding stroma to define the loss of heterozygosity (LOH) associated with chromosome 6p21. Our results showed that LOH in chromosome 6 produced HLA haplotype loss (phenotype II) in 36% of the tumors. In addition, HLA class I total loss (phenotype I) was found in 11%; HLA A or B locus downregulation (phenotype III) was detected in 20%; and HLA class I allelic loss (phenotype IV) in 10% of all cases. We sometimes observed two or more associated mechanisms in the same HLA-altered phenotype, such as LOH and HLA total loss in phenotype I. In only 23% of tumors it was not possible to identify any HLA class I alteration. We conclude that the combination of immunohistological techniques and molecular analysis of tumor DNA obtained from microdissected tumor tissues provides a means for the first time of determining the actual frequency of the major HLA class I-altered phenotypes in laryngeal carcinomas. 相似文献