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41.
This paper suggests a new approach for providing intelligence in the system for diagnosis of diseases of the oilseed-crops. It reports the development of a web-based intelligent disease diagnosis system (WIDDS). The WIDDS is based on a new fuzzy logic approach. The approach is based on use of a rule-promotion methodology. This approach enables the drawing of inferences with the enhanced intelligence. The WIDDS also incorporates new features that improve the presently existing expert systems. The new features are (i) object-oriented (O-O) inference model, (ii) dynamic knowledge base creation strategy. The dynamically promoted rules are derived from those diagnosis sessions, which resulted in successful decisions. This enables more efficient decision-making in the future sessions, (iii) audio-visual-graphical user interface using text-to-speech (TTS) conversion tools. The WIDDS results in decreasing not only the number of interactive question-answer sessions with the clients but also leads to acceptable diagnosis. Further, the inferences are drawn faster compared to the traditional approach, which is the expert based reasoning method. The suggested WIDDS, which is based on rule-promotion approach, has been tested for three oilseeds crops - soybean, groundnut and rapeseed-mustard.  相似文献   
42.
The silphinenes are tricyclic sesquiterpenes that have antifeedant and toxic effects in insects and structural similarity to the known GABA antagonist, picrotoxinin. In murine synaptoneurosomes, silphinenes block GABA-stimulated influx of 36Cl with EC50s in the range of 10-30 μM. In insects, silphinenes were tested in neurophysiological recordings of central neurons from third instar Drosophila melanogaster larvae. Silphinenes reversed the blockage of neuronal firing induced by GABA, but had little effect below 100 μM. The structure-activity profile observed in the murine chloride flux assay was also observed in the larval neurophysiological assay, indicating little selectivity for the silphinenes. A reference silphinene was equally active on nerve preparations from the rdl strain of D. melanogaster, which is resistant to channel-blocking antagonists via an altered GABA receptor. This latter finding suggests that silphinenes interact with the insect GABA receptor in a manner somewhat different from PTX, and that rdl resistance in the field may have little effect on silphinene efficacy.  相似文献   
43.
The present study was aimed to investigate the relationship between selected morphological traits of teat and subclinical mastitis (SCM) in Frieswal crossbred dairy cows. A total of 1040 quarters from 261 lactating cows were evaluated for teat shape (bottle/fleshy/collapsed/conical/normal/pencil and short), teat-end shape (dished/flat/funnel/pocketed/pointed and rounded), teat orientation (aligned/misaligned) and teat position (front and rear; left-sided and right-sided). Each udder quarter was screened with California Mastitis Test (CMT) for the purpose of defining quarter health status. Data were analysed using Chi-square test and multivariable logistic regression procedure. An overall prevalence of SCM (CMT positive) at quarter level was 30.6%. Most of the teats had normal or cylindrical shapes (48%), dished teat-ends (40.7%), and aligned (central or squared) in orientation (65%). At bivariable level, significant association of SCM with teat shape, teat position, teat orientation, parity, and stage of lactation was observed (P < 0.05 to P < 0.001). Teat-end shapes showed some association with SCM (P = 0.07). Results of multivariable analysis showed that pencil-shaped teats were least associated with SCM (P < 0.05) as compared to other teat shapes. Prevalence of SCM was also higher in rear teats (P = 0.015), misaligned teats (P = 0.01), and cows in second or higher parities (P < 0.01) and late stage of lactation (P < 0.001). The results of the present study indicate that selected morphological traits of teat are associated with SCM in Frieswal crossbred cows; therefore, selection towards desirable morphological traits could help reduce mastitis in this breed.  相似文献   
44.
45.
Objectives: To report the repair of tibial diaphyseal fractures in 2 calves using a circular external skeletal fixator (CEF). Study Design: Clinical report. Animals: Crossbred calves (n=2; age: 6 months; weight: 55 and 60 kg). Methods: Mid‐diaphyseal tibial fractures were repaired by the use of a 4‐ring CEF (made of aluminum rings with 2 mm K‐wires) alone in 1 calf and in combination with hemicerclage wiring in 1 calf. Results: Both calves had good weight bearing with moderate lameness postoperatively. Fracture healing occurred by day 60 in 1 calf and by day 30 in calf 2. The CEF was well maintained and tolerated by both calves through fracture healing. Joint mobility and limb usage improved gradually after CEF removal. Conclusions: CEF provided a stable fixation of tibial fractures and healing within 60 days and functional recovery within 90 days. Clinical Relevance: CEF can be safely and successfully used for the management of selected tibial fractures in calves.  相似文献   
46.
47.
The oomycete Phytophthora colocasiae that causes taro leaf blight is the most devastating disease of taro and is widely distributed worldwide. Molecular and phenotypic techniques were employed for assessing and exploiting the genetic variability among four populations of P. colocasiae obtained from a fine spatial scale (multiple leaf blight lesions on single taro leaf). Phenotypic characters such as virulence, morphology and mating type showed no variation. ITS characterization revealed detectable polymorphism among isolates of P. colocasiae. The mean number of haplotypes (H), haplotype diversity (HD), nucleotide diversity (π), and nucleotide substitution rate (θ) among analyzed sequences were 6.75, 1.00, 0.069, and 0.088 respectively. High levels of inter and intra specific variation were detected by random amplified polymorphic DNA (RAPD) assays. Moderate genetic diversity (H?=?0.2651) was observed among populations of P. colocasiae. Analysis of molecular variance (AMOVA) confirmed that most of the genetic variability was confined to within a population (63.54 %). The coefficient of genetic differentiation among populations (G ST ) was 0.2007 and estimates of gene flow (Nm) among populations was 1.991 migrants per generation. Cluster analysis using UPGMA revealed that individuals from the same population failed to cluster in one distinct group. The results of the study reveal considerable genetic diversity among and within populations of P. colocasiae obtained from fine spatial scale. The possible mechanisms and implications of this genetic variation are discussed.  相似文献   
48.
Cell suspension cultures were derived from adventitious somatic embryos induced on cotyledons of rescued peach embryos. Embryogénie calli were induced and established on modified MS medium supplemented with 2,4-D, BAP, KN and inositol. Development of embryos during suspension cultures was identified by growth pattern and by histological and cytological examination, using acetocarmine stain. More embryogenic calli were produced using 2,4-D (5 (µM) than NAA. A gradual reduction of 2,4-D increased the recovery of globular embryos. Heart-stage embryos were developed on high-nitrogen salt medium, with added Ca(N03)2 (1000 mg I"1) and 6% sucrose. Somatic embryos turned green and sometimes red under white light. Embryo viability was highest when subculturing every 14 days. Viability of cells and differentiating embryos was assessed, microscopically, with Alexander’s stain. Viable embryos reacted pink to red while non- viable embryos reacted green to blue. Embryogenic cell suspension cultures were maintained for over ten months by regular subculturing after two weeks on modified MS medium with low 2,4-D, BAP and KN.  相似文献   
49.
Calcium phosphate (CaP) particles were coupled with inactivated Newcastle disease virus (NDV) vaccine. The surface morphology of CaP particles coupled to NDV was found to be spherical, smooth and with a tendency to agglomerate. The mean (± SE) size of CaP particles was found 557.44 ± 18.62 nm. The mean percent encapsulation efficiency of CaP particles coupled to NDV assessed based on total protein content and haemagglutination (HA) activity in eluate was found to be 10.72 ± 0.89 and 12.50 ± 2.09, respectively. The humoral and cell mediated immune responses induced by CaP coupled NDV vaccine were assessed in comparison to a commercial live vaccine (RDV ‘F’). CaP coupled NDV vaccine elicited prolonged haemagglutination inhibition (HI) and enzyme linked immunosorbent assay (ELISA) titres in the serum even at fourth and fifth week post-vaccination (PV), unlike RDV ‘F’ inoculated chickens whose titres declined to insignificant levels by this time. CaP coupled NDV vaccine could stimulate HI antibodies in tracheal washings and tears from second and first week PV, respectively. IgA ELISA antibodies were also seen in tracheal washings of these birds from third week PV and in tears from second week PV. CaP coupled NDV vaccine elicited cell mediated immune responses (CMI) from two to four weeks PV. The stimulation indices obtained after stimulation with specific antigen was not significantly different between CaP coupled antigen and live NDV virus except on first week PV. However, CaP coupled antigen did not cause suppression of lympo proliferation as indicated by statistically similar responses to mitogen, concanavalin A between the two groups. Overall, CaP coupled NDV vaccine elicited stronger and prolonged immune responses in comparison to the commercial live vaccine. No increase in the serum calcium and phosphorous levels were seen in CaP coupled NDV vaccine inoculated chickens.  相似文献   
50.
Monocarboxylate transporters (MCTs) support tumour growth by regulating the transport of metabolites in the tumour microenvironment. High MCT1 or MCT4 expression is correlated with poor outcomes in human patients with head and neck squamous cell carcinoma (HNSCC). Recently, drugs targeting these transporters have been developed and may prove to be an effective treatment strategy for HNSCC. Feline oral squamous cell carcinoma (OSCC) is an aggressive and treatment‐resistant malignancy resembling advanced or recurrent HNSCC. The goals of this study were to investigate the effects of a previously characterized dual MCT1 and MCT4 inhibitor, MD‐1, in OSCC as a novel treatment approach for feline oral cancer. We also sought to determine the potential of feline OSCC as a large animal model for the further development of MCT inhibitors to treat human HNSCC. In vitro, MD‐1 reduced the viability of feline OSCC and human HNSCC cell lines, altered glycolytic and mitochondrial metabolism and synergized with platinum‐based chemotherapies. While MD‐1 treatment increased lactate concentrations in an HNSCC cell line, the inhibitor failed to alter lactate levels in feline OSCC cells, suggesting an MCT‐independent activity. In vivo, MD‐1 significantly inhibited tumour growth in a subcutaneous xenograft model and prolonged overall survival in an orthotopic model of feline OSCC. Our results show that MD‐1 may be an effective therapy for the treatment of feline oral cancer. Our findings also support the further investigation of feline OSCC as a large animal model to inform the development of MCT inhibitors and future clinical studies in human HNSCC.  相似文献   
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