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1.
H. Y. Mohan Ram  Rina Sett 《Planta》1980,149(4):413-415
Aqueous solutions of silver nitrate (10–100 g/plant) and cobalt chloride (125–500 g/plant), injected into the main stem of plants of the pistillate cv. 240 ofRicinus communis when the vegetative shoot apex was beginning to become reproductive, induced the formation of staminate (male) flowers with viable pollen in the normally strictly pistillate (female) terminal inflorescence, their number increasing with the dose of Ag+ and Co2+. No formation of bisexual flowers was noted. Female flowers pollinated with pollen from the induced male ones produced fruits and viable seeds.  相似文献   
2.
    
We synthesized modified 2'-deoxyuridine triphosphates bearing amino acids at the C5 position and investigated their substrate properties for KOD Dash DNA polymerase during polymerase chain reaction (PCR). PCR using C5-modified dUTP having an amino acyl group (arginyl, histidyl, lysyl, phenylalanyl, tryptophanyl, leucyl, prolyl, glutaminyl, seryl, O-benzyl seryl or threonyl group) gave the corresponding full-length PCR products in good yield. Although dUTP analogues bearing aspartyl, glutamyl or cysteinyl were found to be poor substrates for PCR catalyzed by KOD Dash DNA polymerase, optimization of the reaction conditions resulted in substantial generation of full-length product. In the case of reaction using dUTP analogue having a cysteinyl group, addition of a reducing agent improved the reaction yield. Thus, PCRs using KOD Dash DNA polymerase together with amino acyl dUTP provide convenient and efficient preparation of various modified DNA libraries with potential protein-like activities.  相似文献   
3.
Thirty-one endophytic bacteria isolated from healthy leaves of Centella asiatica were screened in vitro for their ability to reduce the growth rate and disease incidence of Colletotrichum higginsianum, a causal agent of anthracnose. Isolates of Cohnella sp., Paenibacillus sp. and Pantoea sp. significantly stimulated the growth rate of C. higginsianum MUCL 44942, while isolates of Achromobacter sp., Acinetobacter sp., Microbacterium sp., Klebsiella sp. and Pseudomonas putida had no influence on this plant pathogen. By contrast, Bacillus subtilis BCA31 and Pseudomonas fluorescens BCA08 caused a marked inhibition of C. higginsianum MUCL 44942 growth by 46 and 82 %, respectively. Cell-free culture filtrates of B. subtilis BCA31 and P. fluorescens BCA08 were found to contain antifungal compounds against C. higginsianum MUCL 44942. Inoculation assays on in vitro-cultured plants of C. asiatica showed that foliar application of B. subtilis BCA31, three days before inoculation with C. higginsianum MUCL 44942, significantly reduced incidence and severity of the disease. The role of endophytic bacteria in maintaining the apparent inactivity of C. higginsianum MUCL 44942 in C. asiatica grown in the wild is discussed.  相似文献   
4.

Introduction

Recent studies suggest that heat is associated with an increase in the number of ambulance calls and emergency department visits. We investigated the association between heat and daily number of emergency department visits at the University Hospital of Verona during the warm seasons 2011–2012 and we assessed the magnitude of the impact in terms of attributable events, focusing on the role of age and triage codification.

Materials and methods

We used a Poisson model to analyse the association between daily number of visits and daily mean apparent temperature, accounting for air pollution level and seasonality. The analyses were stratified by age group and were performed both on the total number of emergency department visits and on the subsample of high-priority visits. Impact estimates were obtained only for this subsample, using a Monte Carlo approach to account for sampling variability. Number of attributable events and attributable community rate were calculated.

Results

We found a positive and immediate association between event occurrence and mean apparent temperatures exceeding a threshold located around 28–29°C. The estimated percent change in the total number of visits per 1°C increase of exposure above the threshold was equal to 3.75 (90% CI: 3.01; 4.49). Focusing only on high-priority visits, the estimated percent change was larger and the greatest effect was among children. We estimated that apparent temperatures above the threshold were responsible for 1177 high-priority visits during the study period. Due to the record high temperatures observed in 2012 in Italy and in Europe, the impact in 2012 was much larger than in 2011, and consisted in 34 high-priority visits every 10000 children, 30 every 10000 people aged 15–64, and 38 every 10000 people aged 65 and over.

Discussion

Our results indicate that heat affects not only the elderly, but also children and non-elderly adults, stressing the need for developing public health preparedness plans for the entire community.  相似文献   
5.
    
Journal of Plant Research - Elevational changes in vegetation are associated with changes in environmental factors, an example of which is provided by the shade-tolerant Abies mariesii and less...  相似文献   
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7.
Immunostimulatory and growth promoting properties of Achyranthes aspera seeds were studied with larvae of common carp Cyprinus carpio. Four experimental diets were prepared using raw (D1) and alcohol (D2), petroleum ether (D3) and 50% aqueous alcohol (D4) extracts of A. aspera seeds. Diet without seed served as control (D5). Fish were fed with test/control diet for 30 days and then immunized with 10 μl of c-RBC. Blood samples were collected 7 days after immunization. Survival (93 ± 3%) of fish was significantly (P < 0.05) higher in D1 diet fed group compared to others. Highest specific growth rate was found in fish fed with diet D2. Significantly (P < 0.05) higher levels of serum protein and albumin were found in D1 and D3 compared to others. Highest serum globulin level was found in D1, which was followed by D3, D2, D4 and D5. Hemagglutination titer level was 5-18 folds higher in diet D3 fed fish compared to others. SGOT and SGPT levels were significantly (P < 0.05) higher in control group compared to the treated groups. Myeloperoxidase activity was significantly (P < 0.05) higher in D1 (2.513 ± 0.27 λ 450 nm) and D3 (2.38 ± 0.07 λ 450 nm) diets fed groups compared to others. The best performance of fish was found in raw A. aspera seeds incorporated diet fed group and the active constituents were identified as ecdysterone and two essential fatty acids linolenic acid and oleic acid.  相似文献   
8.
Soluble NSF attachment protein receptors (SNAREs) are the core proteins in membrane fusion. The neuron-specific synaptic v-SNARE n-syb (neuronal Synaptobrevin) plays a key role during synaptic vesicle exocytosis. In this paper, we report that loss of n-syb caused slow neurodegeneration independent of its role in neurotransmitter release in adult Drosophila melanogaster photoreceptor neurons. In addition to synaptic vesicles, n-Syb localized to endosomal vesicles. Loss of n-syb lead to endosomal accumulations, transmembrane protein degradation defects, and a secondary increase in autophagy. Our evidence suggests a primary defect of impaired delivery of vesicles that contain degradation proteins, including the acidification-activated Cathepsin proteases and the neuron-specific proton pump and V0 adenosine triphosphatase component V100. Overexpressing V100 partially rescued n-syb-dependent degeneration through an acidification-independent endosomal sorting mechanism. Collectively, these findings reveal a role for n-Syb in a neuron-specific sort-and-degrade mechanism that protects neurons from degeneration. Our findings further shed light on which intraneuronal compartments exhibit increased or decreased neurotoxicity.  相似文献   
9.
Among the most popular motifs in Francis Bacon’s painting is the gaping mouth. In some works the expression appears to be a scream, while elsewhere the mouth is open, replete with upper and lower teeth, but beyond that it is unclear whether we are seeing a mouth that is screaming or making some other expression. This article conveys the importance of the mouth as a “lever” for prising apart the human. Through the open mouth Bacon exposes the human-animal and reduces the mouth—as an organ of speech, reason and humanity—to its primal and pre-linguistic function. In demonstrating this it will be argued that rather than focusing exclusively on the scream, more attention needs to be paid to the gaping mouth and its significance in Bacon’s ?uvre.  相似文献   
10.
Multiple sclerosis (MS) is no longer considered to be simply an autoimmune disease. In addition to inflammation and demyelination, axonal injury and neuronal loss underlie the accumulation of disability and the disease progression. Specific treatment strategies should thus aim to act within the central nervous system (CNS) by interfering with both neuroinflammation and neurodegeneration. Specific treatment strategies to autoimmune neurological disorders should aim to act within the CNS by interfering with both neuroinflammation and neurodegeneration. The cumulative effect of Glatiramer acetate (GA; Copaxone(R), Copolymer 1), an approved drug for the treatment of MS, reviewed herewith, draws a direct linkage between anti-inflammatory immunomodulation, neuroprotection, neurogenesis, and therapeutic activity in the CNS. GA treatment augmented the three processes characteristic of neurogenesis, namely, neuronal progenitor cell proliferation, migration, and differentiation. The newborn neurons manifested massive migration through exciting and dormant migratory pathways, into injury sites in brain regions, which do not normally undergo neurogenesis, and differentiated to mature neuronal phenotype, thus, counteracting the neurodegenerative course of disease. The plausible mechanism underlying this multifactorial effect is the induction of GA-reactive T cells in the periphery and their infiltration into the CNS, where they release immunomodulatory cytokines and neurotrophic factors in the injury site.  相似文献   
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