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排序方式: 共有147条查询结果,搜索用时 31 毫秒
1.
International Journal of Peptide Research and Therapeutics - Klebsiella oxytoca is a gram-negative bacterium. It is opportunistic in nature and causes hospital acquired infections....  相似文献   
2.
Three new eremophilane sesquiterpenes phomadecalins G−I ( 1 – 3 ) and two new benzene derivatives microdiplzenes A and B ( 12 and 13 ), together with nine known eremophilane sesquiterpenes ( 4 – 11 and 14 ) were isolated from an endophytic fungus, Microdiplodia sp. WGHS5. Their structures were elucidated by the interpretation of HR-ESI-MS and NMR data; meanwhile, the absolute configurations of new compounds were determined on the base of ECD calculations. All compounds were evaluated for the antimicrobial activities and antiproliferative effect on human gastric cancer cell lines (BGC-823).  相似文献   
3.

Background

There is little information about influenza among the Pakistani population. In order to assess the trends of Influenza-like-Illness (ILI) and to monitor the predominant circulating strains of influenza viruses, a country-wide lab-based surveillance system for ILI and Severe Acute Respiratory Illness (SARI) with weekly sampling and reporting was established in 2008. This system was necessary for early detection of emerging novel influenza subtypes and timely response for influenza prevention and control.

Methods

Five sentinel sites at tertiary care hospitals across Pakistan collected epidemiological data and respiratory samples from Influenza-like illness (ILI) and severe acute respiratory illness (SARI) cases from January 2008 to December 2011. Samples were typed and sub-typed by Real-Time RT-PCR assay.

Results

A total of 6258 specimens were analyzed; influenza virus was detected in 1489 (24%) samples, including 1066 (72%) Influenza type A and 423 (28%) influenza type B viruses. Amongst influenza A viruses, 25 (2%) were seasonal A/H1N1, 169 (16%) were A/H3N2 and 872 (82 %) were A(H1N1)pdm09. Influenza B virus circulation was detected throughout the year along with few cases of seasonal A/H1N1 virus during late winter and spring. Influenza A/H3N2 virus circulation was mainly observed during summer months (August-October).

Conclusions

The findings of this study emphasize the need for continuous and comprehensive influenza surveillance. Prospective data from multiple years is needed to predict seasonal trends for vaccine development and to further fortify pandemic preparedness.  相似文献   
4.
Respiratory syncytial virus (RSV) is the major cause of acute lower respiratory tract infections in young children, but very little is known about its epidemiology and circulating genotypes in Pakistan. This study analyzed the epidemiological and molecular characteristics of RSV genotypes detected in Pakistani children less than 2 years of age with acute respiratory tract infections (ARIs) in a tertiary care hospital in Gilgit Baltistan (GB) province during 2011-12 winter season. RSV was detected in 75 out of 105 children presenting with acute respiratory infection. Male infants between 2-6 months age made up the highest percentage of RSV positive cases. Epidemiological factors such as pre-maturity, mean weight, clinical features and diagnosis when compared between RSV positive and negative groups were found to be statistically insignificant. Phylogenetic analysis classified all 75 of the RSV strains into 71 strains of subgroups A and 4 strains of subgroup B, respectively. Strains belonging to subgroups A and B were further subdivided into NA1/GA2 and BA, respectively. The nucleotide and deduced amino acid sequence identities were relatively high among these strains (>90%). Both RSV-A and RSV-B isolates had two potential N-glycosylation sites in HVR2 of G protein and with heavy O-glycosylation of serine and threonine residues (G scores of 0.5-0.7). This report highlights the significance of RSV as a dominant viral etiologic agent of pediatric ARIs, and need for continued molecular epidemiological surveys for early detection of prevalent strains and newly emerging genotypes to understand epidemiology of RSV infections in various regions of Pakistan.  相似文献   
5.
Naeem  M.  Nabi  Aarifa  Aftab  Tariq  Khan  M. Masroor A. 《Protoplasma》2020,257(3):871-887
Protoplasma - Recently, a promising technique has come forward in field of radiation-agriculture in which the natural polysaccharides are modified into useful oligomers after depolymerization....  相似文献   
6.
Journal of Plant Growth Regulation - Interest in the use of the nanoparticles as plant growth elicitors mushroomed within the last decade and the field is quite intriguing to meet the growing needs...  相似文献   
7.
基质有效性调节加拿大一枝黄花入侵对土壤呼吸的抑制作用 外来植物入侵不仅会降低河边近岸湿地生态系统植被多样性,而且会改变湿地生态系统的地下碳过程。外来入侵植物加拿大一枝黄花(Solidago canadensis L.)已广泛入侵我国东南部地区,但加拿大一枝黄花入侵对入侵地生态系统地下土壤碳循环过程的影响却知之甚少。本研究通过野外原位观测实验和温室模拟入侵实验,探究外来植物加拿大一枝黄花入侵对入侵地土壤呼吸的影响规律及其驱动因素。野 外原位观测实验开展于2018年7月21日至12月15日,期间每周测定样地土壤呼吸。温室模拟入侵实验开展于2019年7月15日至12月15日,期间每月1日与15日上午测定土壤呼吸、自养呼吸和异养呼吸。土壤呼吸、自养呼吸和异养呼吸通过静态箱结合深埋根系隔离法测定。野外原位观测实验和温室模拟入侵实验结果均显示,加拿大一枝黄花的入侵降低了土壤二氧化碳的排放通量。加拿大一枝黄花入侵对土壤呼吸的抑制作用可能归因于其入侵引起的土壤可利用底物质量与数量的变化,表明外来入侵植物加拿大一枝黄花可通过改变植物释放基质以及与本地植物和/或土壤微生物争夺土壤有效基质而影响土壤碳循环。这些研究结果对于评估外来入侵植物对入侵地地下碳动态的影响以及对全球变暖的贡献具有重要意义。  相似文献   
8.
We report the case of a patient with severe diffuse peripheral vascular disease, coronary artery disease, congestive heart failure, and gastrointestinal bleeding with a pseudoaneurysm of descending thoracic aorta who underwent successful Dacron patch aortoplasty. She was not a candidate for stent-graft repair because of poor access. Using a partial occluding clamp, the pseudoaneurysm was excised and the aorta repaired with a 3.5-cm Dacron patch. She was discharged home in 7 days and has successfully undergone stenting of the left subclavian artery and right and left carotid endarterectomy.  相似文献   
9.
Biodiesel is considered as a potential alternative energy source, but problem exists with the quantity and quality of feedstock used for it. To improve the feedstock quality of biodiesel, a field experiment was conducted under natural conditions. Cultivar Thori of kasumbha was used in the experiment. Commercialized biofertilizers were applied at the rate of 20 kg per acre and chemical fertilizer (diammonium phosphate) was applied as half dose (15 kg/ha). Results indicated that number of leaf plant−1, leaf area, number of seeds capitulum−1 was significantly increased by biofertilizer treatment alone (BF) and combine treatment of biofertilizer and chemical fertilizer (BFCF). Agronomic traits such as plant height, no. of branches of a plant, no. of capitulum/plant was improved significantly by BF treatment over the control. Maximum 1000 seed weight (41%) and seed yield (23%) were recorded in half dose of chemical fertilizers treatment (CFH). Seed oil content and seed phenolics were significantly improved by BF and CF treatments while maximum biodiesel yield was recorded by BF treatment. Maximum oleic acid was recorded by BF treatment while other fatty acids being maximum in control except linoleic acid in BFCF treatment. Results for specific gravity were non-significant while acid value and free fatty acid contents were substantially reduced by BF treatment as compared to other treatments. Maximum value of iodine number was recorded in BFCF treatment while tocopherol contents were improved by BF treatment. It is inferred that biofertilizer treatment alone perform better as compared to other treatments and 50% chemical fertilizer can be replaced using biofertilizer which is a good approach for sustainable environmental-friendly agriculture.Keyword: Green energy, Biofuel, Biodiesel, Kasumbha, Biofertilizers, Fatty acid, NMR  相似文献   
10.
We studied how the relationship between cadmium (Cd) toxicity and oxidative stress influenced the growth, photosynthetic efficiency, lipid peroxidation, and activity of ntioxidative enzymes in the roots and leaves of rice(Oryza sativa L Dongjin). Plants were exposed to Cd for 21 d. Both seedling growth and photosynthetic efficiency decreased gradually with increasing cadmium concentrations. Lipid peroxidation increased slowly in both roots and leaves, causing oxidative stress. However, each tissue type responded differently to Cd concentrations with regard to the induction/ inhibition of antioxidative enzymes. The activity of Superoxide dismutase (SOD) increased in both roots and leaves. Ascorbate peroxidase (APX) activity increased in leaves treated with up to 0.25 μM Cd, then decreased gradually at higher concentrations. In contrast, APX activity in roots increased and remained constant between 0.25 and 25 μM Cd. Enhanced peroxidase (POD) activity was recorded for treatments with up to 25/M Cd, gradually decreasing at higher concentrations in the leaves but remaining unchanged in the roots. Catalase (CAT) activity increased in the roots, but decreased in the leaves, whereas the activity of glutathione reductase (GR) was enhanced in both roots and leaves, where it remained elevated at higher Cd concentrations. These results suggest that rice seedlings tend to cope with free radicals generated by Cd through coordinated, enhanced activities of the antioxidative enzymes involved in detoxification.  相似文献   
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