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41.
Cigarette smoke toxicants are well known for their debilitating effects on lungs. Cigarette smoke toxicities cause various respiratory disorders including pulmonary emphysema, chronic obstructive pulmonary disease (COPD), pulmonary fibrosis and cancer. Farnesol, an isoprenoid, is known to possess anti-inflammatory and chemopreventive properties. In this study we report the protective efficacy of farnesol against massive lung inflammation, oxidative stress and consequent injuries caused by cigarette smoke toxicants. Farnesol was administered by gavage (50 and 100 mg/kg b.wt. in corn oil) one time daily for 7 days. On day 7 lung injuries were induced by intratracheal instillation of aqueous cigarette smoke extract (CSE). LDH, total cell count, total protein, phospholipid content and MDA formation were measured in bronchoalveolar lavage fluid (BALF). In lung tissue H2O2 content, reduced glutathione (GSH), glutathione reductase (GR), glutathione peroxidase (GPx) and catalase activities were evaluated. Prophylactic treatment with farnesol significantly shows lung protection by lowering the levels of LDH, total cell count, total protein and MDA in BALF. Farnesol maintained the phospholipid content of BALF in a positive manner. In lung tissue it positively modulated the CSE altered activities of GR, GPx and catalase. There was a marked increase in GSH content and decrease in H2O2 content of lung tissue by farnesol administration. Histopathological findings correlate with cellular and biochemical parameters of the lungs and potentiate the protective role of farnesol against CSE induced lung inflammation and injuries. These results suggest a potent role of farnesol in protection of lung against cigarette smoke toxicants induced lung injuries. 相似文献
42.
Porcine gene discovery by normalized cDNA-library sequencing and EST cluster assembly 总被引:7,自引:0,他引:7
43.
An epidemiological study was carried out to determine the prevalence of Chlamydia infections in adult females by enzyme immunoassay and microscopic examination of Giemsa-stained smears. Endocervical swabs were collected from 126 females attending OB/GYN ward at Abbasi Shaheed Hospital, Karachi. 13.5% of 126 females tested were positive by enzyme immunoassay and only 5.6% were positive by the Giemsa-staining method. The infection rate among pregnant and nonpregnant women with urinogenital problems were 11.8% and 14.7%, respectively. The majority of females complained of excessive cervical discharge and pain in the lower abdomen. A high prevalence of infection in normal pregnant women (18.2%) indicates the asymptomatic nature of this infection. 相似文献
44.
The phytoplankton productivity of Georgian Bay was studied during 1974. Lakewide samples were collected at 16 stations during monthly cruises from April to December and identification and enumeration was carried out by the Utermohl technique. Contaminant bioassays with metals added singly and as a mixture were performed in 1980 and 1981. Based on an overall average, Diatomeae (36–73%) was the most prevalent component of phytoplankton biomass followed by Chrysophyceae (5–38%), and Cyanophyta (3–27%). Biomass means of all stations by cruise indicated a range of 0.35 to 0.61 g·m–3 with a bimodal seasonal pattern. Although ultraplankton made the highest mean percent contribution to the biomass (37%), the other size assemblages such as < 5 µm (26%) and netplankton (29%) were not unimportant.Size fractionation of primary productivity during 1974 revealed that a major portion of photosynthesis (39–70%) was in the <20 µm size fraction. Algal Fractionation Bioassays conducted during 1980 and 1981 indicated a significant inhibition of ultraplankton productivity. Additional bioassays with single metals and in combination showed differential toxicity to various phytoplankton size assemblages.The phytoplankton biomass and floristic composition indicate the Georgian Bay ecosystem to be oligotrophic. This ecosystem appears to be controlled by the physical dynamics of thermal and flow regimes. Compared with other Great Lakes, the low P/B quotients recorded in oligotrophic Georgian Bay is enigmatic and may be attributable to the observed sensitivity of phytoplankton to contaminants originating from anthropogenic and natural sources. 相似文献
45.
The use of a multi-trophic assay strategy is now being encouraged in toxicological investigations which provides for rapid and sensitive tests. Such a strategy, a microcomputer-based algal fluorescence technique, was applied for the bioassessment of Lake St. Clair and St. Clair River ecosystems. The technique was found to be rapid, sensitive, and relatively inexpensive. In addition, it permitted microscopic examination of the impact of contaminants on individual cells/organisms, a feature which is not possible by other tests using radioisotopes and enzymes. The algal fluorescence technique appears to have a considerable potential for fast screening of large numbers of environmental samples. 相似文献
46.
Razia Sultana 《Biocontrol Science and Technology》2016,26(2):145-162
The mulberry tree is an important crop for silkworm farming and for the health care industry. In Asia, the annual productivity of mulberry fruits is greatly reduced due to popcorn disease mainly caused by Ciboria shiraiana, a sclerotia-forming fungal pathogen. To date, the development of efficient biocontrol agents (BCAs) against this disease has been hampered by the recalcitrance of C. shiraiana to in vitro culturing methods. Here, we established alternative in vitro antifungal assays that directly monitored the effects of BCAs on the growth of C. shiraiana apothecia and further reported that Bacillus thuringiensis C25 suppressed popcorn disease in field conditions. Initially, from mulberry drupelets showing the popcorn disease symptoms, we confirmed the infection of C. shiraiana and observed its morphology in asexual stage. Then, apothecia of C. shiraiana were induced from the sclerotia collected from the disease-infested orchard. Two bacterial isolates, Enterobacter sp. C5 and B. thuringiensis C25, strongly suppressed the elongation and fresh weight accumulation of apothecia stalks, the width of hymenium, and ascus and ascospore formation of C. shiraiana. In addition, both bacterial isolates degraded the ultrastructure of hymenium cells in C. shiraiana apothecia. Ultimately, treatment of mulberry trees with B. thuringiensis C25 mitigated the incidence of popcorn mulberry disease under field conditions. In conclusion, B. thuringiensis C25 is the first reported BCA shown to efficiently control mulberry popcorn disease. Our results also support that B. thuringiensis exerts diverse biocontrol roles in addition to insecticidal behaviour. 相似文献
47.
48.
Length‐weight and length‐length relationships of three small indigenous fishes from the Payra River,southern Bangladesh 下载免费PDF全文
F. Ahamed N. Saha M. A. Nishat M. K. Biswas M. Sultana M. S. Khatun Z. F. Ahmed M. Y. Hossain J. Ohtomi 《Zeitschrift fur angewandte Ichthyologie》2018,34(3):777-779
Length‐weight relationships (LWRs) and length‐length relationships (LLRs) for three small indigenous fishes (Esomus danrica, Pachypterus atherinoides and Salmostoma bacaila) were reported from the Payra River, southern Bangladesh. Samples were collected using traditional fishing gear including cast net (mesh size ranges from 1.0 to 2.0 cm), seine net (mesh size ranges from 1.5 to 2.5 cm) and square lift net (mesh size ~ 1.0 cm) in August to September 2017. Allometric coefficient (b) values were 2.66 for E. danrica, 3.08 for P. atherinoides and 3.06 for S. bacaila. The LLRs were also highly significant with r2 ≥ .956. 相似文献
49.
50.
新疆四个民族中12对遗传性状基因频率分布的研究 总被引:23,自引:3,他引:23
阿不都拉·巴克 多力坤·买买提 吾司曼江 木明 斯拉木 木尼热Abdulla·Baki Dolikun·Matiyup Osman Moming Silam Munawar 《遗传》1998,20(5):36-38
本文对新疆维吾尔、哈萨克、柯尔克孜、塔吉克族人群的前额发际等12对遗
传性状进行了调查,计算出各个性状的基因频率、并在4个民族之间进行了比较研究。
Abstract:Twelve characters including hair beared on forehead were investigated among Uygur,Kazak,Kirgiz,and Tajik Xinjiang province.The gene frequencies of the twelve characters were calculated and compared among the four minorities. 相似文献