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排序方式: 共有425条查询结果,搜索用时 31 毫秒
1.
Madhu Aneja Thomas J. Gianfagna Prakash K. Hebbar 《Physiological and Molecular Plant Pathology》2005,67(6):1647
An isolate of Trichoderma harzianum Rifai from an infected cacao pod produces and secretes nonanoic (pelargonic) acid into a liquid culture medium. Nonanoic acid (NA) was very inhibitory to spore germination and mycelial growth of two cacao pathogens, Crinipellis perniciosa Stahel and Moniliophthora roreri Cif. H.C. Evans. It was highly active causing 75% inhibition of spore germination in an in vitro assay at a rate as low as 0.09 μM for M. roreri and 0.92 μM for C. perniciosa. Mycelial growth was comparatively less sensitive to inhibition, but still there was a 75% reduction in growth with 0.62 μM in M. roreri and 151 μM NA in C. perniciosa. In contrast, NA did not affect Trichoderma mycelial growth or spore germination at concentrations that were inhibitory to the pathogens. 6-pentyl-α-pyrone was also produced and secreted into the medium by T. harzianum, however; it was not antagonistic to the cacao pathogens. Although a number of metabolites produced by Trichoderma spp. have been identified in the past, this is the first report of NA production and secretion by any Trichoderma. The results suggest that NA may play a role in the successful use of some Trichoderma spp. isolates in the biocontrol of fungal diseases of plants. 相似文献
2.
Keneisenuo Keneisenuo MVSc Om Prakash Choudhary PhD Pranab Chandra Kalita PhD Priyanka Choudhary PhD Arup Kalita PhD Probal Jyoti Doley MVSc Jitendra Kumar Chaudhary PhD 《Anatomia, histologia, embryologia》2021,50(3):500-511
The present study reports data on the skull bone morphometry of barking and sambar deer. The skulls of adult barking deer (n = 6) and sambar deer (n = 6) of either sex (n = 3 males and n = 3 females) were collected from the Aizawl Zoological Park, Aizawl, Mizoram, India, with official permission from the Government of Mizoram. Anatomically, barking and sambar deer's skulls were elongated, pyramid-like, dolichocephalic and consisted of thirty-two cranial and facial bones. The cranial bones were eleven (three single and four paired), comprising of occipital, sphenoid, ethmoid, frontal, interparietal, parietal and temporal. The facial bones were twenty-one (one single and ten were paired), consisting of the maxilla, premaxilla (incisive), palatine, pterygoid, nasal, lacrimal, zygomatic (malar), vomer, turbinates, mandible and hyoid. In the present study, altogether 41 different measurements were taken morphologically and 6 different indices were applied. The obtained morphometrical parameters were significantly (p < .01, p < .05) higher in males than females of both species. Species wise, all obtained parameters were higher in sambar deer than barking deer. The obtained 41 different skull parameters and 6 indices showed statistically significant differences (p < .01 and p < .05) between both sexes of barking and sambar deer; however, practically these differences were meagre. The present morphometrical study on the skull of both species can help the wildlife professionals and zoo veterinarians determine the sex of these animals and differentiate it from other domestic and wild small ruminants for solving veterolegal cases. This study's findings will also motivate and assist other comparative studies with various domestic and wild small ruminants. 相似文献
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Intestinal anastomoses were performed on seventeen mongrel dogs by non-suture invagination technique and by the conventional method. A comparative evaluation revealed the non-suture technique to be easier and less time-consuming. Also the tissue reaction was minimal. Encouraging results suggest further investigation prior to clinical trial of this relatively new technique. Résumé. Des anastomoses intestinales sur dix-sept chiens métis par l'invagination technique pas de suture et la méthode de convention. Une évaluation comparative a révélé que la technique pas de suture était plus facile et moins de temps était perdu. Aussi la réaction du tissu était minimum. Les résultats encourageants proposent un surcro***ît d'investigation antérieurement a l'expérience clinique de cette technique relativement plus nouvelle. Zusammenfassung. Die Darmanastomosen von siebzehn Mischhunden durch die Intussuscep-tiontecknik keiner Naht und die verabredete Methode. Eine vergleichende Abschatzung zeigte, daß die Tecknik keiner Naht leichter ist, und wenigere Zeitverschwendung hat. Auch war die Reaktion des Gewebes minderst. Die ermutigenden Ergebnisse suggerieren eine Forderung der Erforschung vor klinischem Versuch dieser Tecknik, die verhältnismäßig neuere ist. 相似文献
6.
Influence of fibrolytic enzymes on the hydrolysis and fermentation of pure cellulose and xylan by mixed ruminal microorganisms in vitro 总被引:3,自引:0,他引:3
Colombatto D Mould FL Bhatt MK Morgavi DP Beauchemin KA Owen E 《Journal of animal science》2003,81(4):1040-1050
A series of in vitro studies was conducted to determine the effects of adding a commercial enzyme product on the hydrolysis and fermentation of cellulose, xylan, and a mixture (1:1 wt/wt) of both. The enzyme product (Liquicell 2500, Specialty Enzymes and Biochemicals, Fresno, CA) was derived from Trichoderma reesei and contained mainly xylanase and cellulase activities. Addition of enzyme (0.5, 2.55 and 5.1 microL/g of DM) in the absence of ruminal fluid increased (P < 0.001) the release of reducing sugars from xylan and the mixture after 20 h of incubation at 20 degrees C. Incubations with ruminal fluid showed that enzyme (0.5 and 2.55 microL/g of DM) increased (P < 0.05) the initial (up to 6 h) xylanase, endoglucanase, and beta-D-glucosidase activities in the liquid fraction by an average of 85%. Xylanase and endoglucanase activities in the solid fraction also were increased (P < 0.05) by enzyme addition, indicating an increase in fibrolytic activity due to ruminal microbes. Gas production over 96 h of incubation was determined using a gas pressure measurement technique. Incremental levels of enzyme increased (P < 0.05) the rate of gas production of all substrates, suggesting that fermentation of cellulose and xylan was enzyme-limited. However, adding the enzyme at levels higher than 2.55 microL/g of DM failed to further increase the rate of gas production, indicating that the maximal level of stimulation was already achieved at lower enzyme concentrations. It was concluded that enzymes enhanced the fermentation of cellulose and xylan by a combination of pre- and postincubation effects (i.e., an increase in the release of reducing sugars during the pretreatment phase and an increase in the hydrolytic activity of the liquid and solid fractions of the ruminal fluid), which was reflected in a higher rate of fermentation. 相似文献
7.
Amanda B McLaughlin Jonathan H Epstein Vibhu Prakash Craig S Smith Peter Daszak Hume E Field Andrew A Cunningham 《Journal of zoo and wildlife medicine》2007,38(3):446-452
Although bats of the genus Pteropus are important ecologically as pollinators and natural hosts for zoonotic pathogens, little is known about their basic physiology. Hematology and plasma biochemistries were determined from wild-caught flying foxes (Pteropus giganteus) in northern India (n=41). Mean lymphocyte differential count was higher for juveniles than adults. Mean platelet count was lower than previously reported. No hemoparasites were observed. No differences were observed between plasma biochemistry values of male and female bats, juveniles and adults, or lactating and nonlactating females. Variation in aspartate aminotransferase (AST) was seen based on body condition score. Blood urea nitrogen and cholesterol concentrations were lower in P. giganteus than other mammalian groups, but were consistent with those reported from other Pteropus species. Alanine aminotransferase and AST concentrations were higher than those reported for Pteropus vampyrus, a closely related species. This study provides basic physiologic information that can be used in future health and disease studies of Indian flying foxes. 相似文献
8.
Chanda Kushwaha Ramesh Chand Chandra Prakash Srivastava 《European journal of plant pathology / European Foundation for Plant Pathology》2006,115(3):323-330
Aeciospores in Uromyces fabae were found to be repeating spores and play an important role in pea rust outbreaks in the North Eastern Plain Zone (NEPZ) of India. Experiments conducted on pea rust from 2001 to 2004 revealed the dominance of aeciospores at all growth stages of pea in this region. Urediospore production was erratic and was only observed in a few samples of stems and tendrils (5–10%). Inoculation of pea plants either by aeciospores or urediospores resulted in the production of aeciospores. Production of aeciospores was observed at a temperature range of 10–25 °C, with a maximum at 25 ± 2 °C. Among the different growth stages of pea, the pod formation stage was highly susceptible and produced the maximum number (744) of aecidia/leaf at 20–25 °C. Significant effects of growth stages and temperature were also noticed for pustule number. Urediospore production mainly coincided with the senescence of the pea plants. Maximum germination (2%) of aeciospores was observed at 25 °C, whereas maximum urediospore germination (3.5%) was at 15 °C. Temperatures > 15 °C decreased urediospore germination. A relative humidity (RH) of 100% was favourable for aeciospore germination while 98% RH favoured urediospore germination. Typical histo-pathological behaviour of the aeciospores was observed. 相似文献
9.
A method to obtain high (> 95 %) and uniform germination of urediniospores of Melampsora medusae on a niembrano filter is described. Such levels of gormination are essential in electrophorotie and other physiological studios of rust fungi. 相似文献
10.
Grakh Kushal Mittal Dinesh Prakash Anand Jindal Naresh 《Veterinary research communications》2022,46(2):537-548
Veterinary Research Communications - Avian pathogenic Escherichia coli (APEC) is responsible for colibacillosis in poultry. APEC remains a constant problem for the poultry industry, despite the use... 相似文献