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排序方式: 共有592条查询结果,搜索用时 15 毫秒
11.
Roy A Biswas SK Chowdhury A Shill MC Raihan SZ Muhit MA 《Pakistan journal of biological sciences: PJBS》2011,14(19):905-908
The objectives of the present study were to investigate phytochemical screening and to assay cytotoxicity and antibacterial activities of ethanolic extracts of leaves of two medicinal plants, Aglaonema hookerianum Schott (Family: Araceae) and Lannea grandis Engl. (Family: Anacardiaceae) available in Bangladesh. The brine shrimp lethality bioassay showed that the ethanolic extracts of Aglaonema hookerianum and Lannea grandis possessed cytotoxic activities with LC50 5.25 (microg mL(-1)) and 5.75 (microg mL(-1)) and LC90 10.47 (microg mL(-1)) and 9.55 (microg mL(-1)), respectively. Two extracts obtained from leaves were examined for their antibacterial activities against some gram positive bacteria such as Bacillus subtilis, Bacillus megaterium and Staphylococcus aureus, also gram negative strains of Pseudomonas aeruginosa, Escherichia coli, Shigella dysenteriae, Salmonella typhi, Salmonella paratyphi and Vibrio cholerae. Agar disc diffusion method was applied to observe the antibacterial efficacy of the extracts. Results indicated that both plant extracts (500 microg disc(-1)) displayed antibacterial activity against all of the tested microorganisms. These results were also compared with the zones of inhibition produced by commercially available standard antibiotic, Amoxicillin at concentration of 10 microg disc(-1). Observed antibacterial properties of the ethanolic extract of Aglaonema hookerianum Schott and Lannea grandis Engl. showed that both plants might be useful sources for the development of new potent antibacterial agents. 相似文献
12.
Canapp SO Farese JP Schultz GS Gowda S Ishak AM Swaim SF Vangilder J Lee-Ambrose L Martin FG 《Veterinary surgery : VS》2003,32(6):515-523
OBJECTIVE: To evaluate the effects of topical glycyl-L-histidyl-L-lysine tripeptide-copper complex (TCC; Iamin 2% Gel; Procyte Corporation, Redmond, WA) on healing in ischemic open wounds. STUDY DESIGN: Experimental study. SAMPLE POPULATION: Twenty-four adult male Sprague-Dawley rats. METHODS: Rats were divided into 3 groups: topical TCC, topical TCC vehicle (hydroxypropyl-methylcellulose), and no treatment (control). Six-mm-diameter, full-thickness wounds were created within an ischemic bipedicle skin flap on the dorsum of each rat. Each day, for 13 days, wound margins were traced, and the TCC and TCC vehicle groups were treated topically. Tracings were scanned, and wound perimeter and area were calculated. On days 6, 10, and 13, selected wounds were biopsied and analyzed for tumor necrosis factor alpha (TNF-alpha) and matrix metalloproteinases (MMP) 2 and 9. RESULTS: A significant decrease in wound area was seen in the TCC group, but not the vehicle group, when compared with the control group on days 3 to 5, 6 to 9, and 11 to 13 and when TCC was compared with TCC vehicle on days 3 and 9. On day 13, initial wound area had decreased by 64.5% in the TCC group, 45.6% in the vehicle group, and 28.2% in the control group. On days 6, 10, and 13, TCC-treated wounds contained significantly lower concentrations of TNF-alpha and MMP-2 and MMP-9 than control wounds. CONCLUSION: Topical TCC resulted in accelerated wound healing in ischemic open wounds. CLINICAL RELEVANCE: Topical TCC is an effective stimulant of healing of ischemic open wounds in rats and may have an application for the treatment of chronic wounds in other species. Clinical evaluation of topical TCC is warranted. 相似文献
13.
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
14.
15.
R. Chandra Babu V. Muralidharan M. Seetha Rani M. Nagarajan S. R. Sree Rangasamy R. K. Pallikonda Perumal 《Journal of Agronomy and Crop Science》1990,164(3):213-216
The effect of seed size on germination and seedling growth was assessed using cultivars of greengram and blackgram. Significant positive correlation was noticed between seed size and germination, seedling height, root length, primary leaf size and seedling weight. The possible advantages of choosing cultivars with heavier seeds for attaining better crop stand especially under rainfed situation are discussed. 相似文献
16.
Renal and biochemical changes produced in broilers by high-protein, high-calcium, urea-containing, and vitamin-A-deficient diets 总被引:1,自引:0,他引:1
Three hundred 18-day-old male chicks (Arbor Acre) were divided into five groups of 60 each and given high-protein (42.28%), high-calcium (3.37%), urea-containing (5%), vitamin-A-deficient, or control diets to study the effect of nutritional imbalances on the development of nephritis and related biochemical changes over 15 weeks. The first four diets increased the levels of glutamate oxaloacetate transaminase, glutamate pyruvate transaminase, uric acid, and nonprotein nitrogen in serum. Blood urea was increased by only the urea diet. Hypoglycemia and a decrease in hepatic glucose-6-phosphatase were also observed in chicks fed the first four diets. The vitamin-A-deficient diet resulted in a depletion of vitamin A in the liver and kidneys. These changes were directly correlated with the prolonged feeding of experimental diets and also with the severity of nephritis and degenerative changes in various organs. It was concluded that increasing the intake of nitrogen or calcium in order to increase production may in fact have the opposite effect, leading to degenerative changes in various tissues and to nephritis. 相似文献
17.
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
18.
Rheum undulatum root has been used traditionally in Korea for the treatment of dental diseases. The purpose of this study was to separate a fraction from R. undulatum showing anti-acid production activity against Streptococcus mutans biofilms and identify the main components in that fraction. Methanol extract of R. undulatum root and its fractions were prepared. To select a fraction exhibiting anti-acid production activity, suspension glycolytic pH-drop assay was performed. Among the fractions tested, dichloromethane fraction exhibited the strongest activity in a dose-dependent manner. To examine the effect of the selected fraction on the anti-acid production of S. mutans biofilms, 74 h old S. mutans biofilms were used. The selected fraction reduced the initial rate of acid production of S. mutans biofilms at sub-minimum inhibitory concentration (MIC) levels. HPLC qualitative analysis of the selected fraction indicated that the presence of anthraquinone derivatives, such as aloe-emodin, emodin, chrysophanol and physcion, as main components. 相似文献
19.
Daniela?Correia?MartinoEmail author Jorge?Luiz?Colodette Richard?Chandra Jack?Saddler 《Wood Science and Technology》2017,51(3):557-569
The steam explosion (SE) pretreatment associated with the organosolv process was investigated to produce dissolving pulp from eucalyptus. Prehydrolysis Kraft (PHK) pulping was also done to produce viscose and acetate grade pulps as reference. The organosolv pulps were delignified in two steps with sodium chlorite. Viscose and acetate grade PHK pulps were bleached by OD0(EH)D1P and OD0(EP)D1PCCE sequences, respectively. Dilute acid-catalyzed (with acid addition) SE pretreatment dissolved more xylan than auto-catalyzed (no acid addition) SE pretreatment. Steam-exploded unbleached organosolv pulps showed lower residual lignin content and screened yield than unbleached organosolv pulps without SE pretreatment. Steam explosion pretreatment helped to decrease lignin content and damaged fiber length of unbleached organosolv pulps. The 1.0% H2SO4 organosolv pulp (organosolv dissolving pulp at bioconversion conditions) showed the highest reactivity. Even showing low viscosity for some applications, in general, the organosolv dissolving pulps produced in this study can be used for making lyocell fibers. 相似文献
20.
Atiqur Rahman Barbhuiya Ayyanadar Arunachalam Prabhat Chandra Nath Mohammed Latif Khan Kusum Arunachalam 《Journal of Forest Research》2008,13(1):25-34
Rates of weight loss and nutrient (N and P) release patterns were studied in the leaf litter of the dominant tree species
(Ailanthus grandis, Altingia excelsa, Castanopsis indica, Duabanga sonneriatioides, Dysoxylum binectariferum, Mesua ferrea,
Shorea assamica, Taluma hodgsonii, Terminalia myriocarpa and Vatica lancefolia) of a tropical wet evergreen forest of northeast India. Nitrogen and phosphorus mineralization rate and decay pattern varied
significantly from species to species. In general, the decay pattern, characterized by using a composite polynomial regression
equation, exhibited three distinct phases of decay during litter decomposition—an initial slow decay phase (0.063% weight
loss day−1), followed by a rapid decay phase (0.494% weight loss day−1) and a final slow decay phase (0.136% weight loss day−1). The initial chemical composition of the litter affected decomposition rates and patterns. Species like D. sonneriatoides, D. binectariferum, and T. hodgsonii with higher N and P content, lower carbon and lignin content, and lower C:N ratio and lignin:N ratio exhibited relatively
faster decomposition rates than the other species, for example M. ferrea, C. indica and A. grandis. A slow decay rate was recorded for species such as M. ferrea, C. indica, and A. grandis. The initial N and P content of litter showed significant positive correlations with decay rates. Carbon and lignin content,
lignin:N, and C:N showed significant negative correlations with decay rates. Soil total N and P, and rainfall, soil temperature,
and soil moisture had positive correlations with decay rates. The rapid decomposition rates observed in comparison with other
different forest litter decay rates confirm that tropical wet evergreen forest species are characterized by faster decomposition
rates, indicating a faster rate of organic matter turnover and rapid nutrient cycling. 相似文献