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1.
Lepcha is the oldest and the first tribe reported from Sikkim, India; majority of its population inhabiting in Dzongu valley, an officially demarcated reserve for Lepcha community, bordering Khangchendzonga Biosphere Reserve, in north district. Lepchas of Dzongu are known for their retention of rich cultural heritage. In view of the on-going cultural and economic changes brought in by the process of globalization, the immediate need was felt to document in details the under-explored ethnomedicinal practices of Lepchas of Dzongu valley. This paper reports 118 species, belonging to 71 families and 108 genera, under ethnomedicinal utility by the Lepchas for curing approximately 66 ailments, which could be grouped under 14 broad categories. Zingiberaceae appeared as the most used family (8 species and 5 genera). As per use pattern, maximum of 30.50% species are to cure stomach related disorders/ailments, followed by 19.49% for curing cut, wounds, inflammation, sprains and joint pains. Administration of medicine orally is recorded in 75% cases. Root and rhizome harvesting targeted 30 species. The changing scenario over time both at socio-cultural front and passing traditional knowledge interests from older to younger generation and rich ethnomicinal wealth of the oldest tribe of Sikkim are discussed in the light of conservation strategies and techniques to adopt.  相似文献   
2.
Plant growth regulator (PGR) application decreased uptake of 10–6 M14C-labeled metribuzin (4-amino-6-(1,1-dimethylethyl)-3-(methylthio)-1,2,4-triazin-5(4H)-one) into leaf interveinal areas of 21-day-old soybean seedlings. BAS 140 810, (N-allyl-N-2-(2,4,6-trichlorophenoxy)ethyl-piperidinium-bromide), as a seed treatment or 10–6 M triapenthenol or RSW 0411 (B-(cyclohexalmethylene)-gamma-(1,1-dimethylethyl)-1H-1,2,4-triazole-1-ethanol) in nutrient solution slowed interveinal unloading of metribuzin and altered metabolite pools. Stems and roots of PGR-treated plants exhibited significantly greater water-soluble metabolite pools than untreated controls. TLC metabolite identification indicated an increase in metribuzin conjugates. This may contribute to the mode of action involved in the apparent safening mechanism. Furthermore, floating leaf disk studies with metribuzin showed plant growth regulation figured prominently in safening against the cessation of oxygen evolution.  相似文献   
3.
A stochastic model describing small eye movements occurring during steady fixation on a stationary target is presented. Based on eye movement data for steady gaze, the model has a hierarchical structure; the principal level represents the random motion of the image point within a local area of fixation while the higher level mimics the jump processes involved in transitions from one local area to another. Target image motion within a local area is described by a Langevinlike stochastic differential equation taking into consideration, the microsaccadic jumps pictured as being due to point processes and the high frequency muscle tremor, represented as a white noise. The transform of the probability density function for local area motion is obtained, leading to explicit expressions for their means and moments. Evaluation of these moments based on the model are comparable with experimental results. A physiologically based criterion for the occurrence of local area changes is assumed and the renewal density of these transitions is obtained. These transitions are brought about by the occurrence of large saccades. Hence, our analysis leads us to derive expressions for the mean and moments of the occurrence of large saccades in a given time T. These predictions may be checked against experimental results.This investigation was supported by National Institutes of Health under Grants Numbers GM 16197-03, GM 16437, and RR-0712-04, by the National Science Foundation under Grant Number GK-1834X, and by the National Aeronautics and Space Administration under Grant Number NGL-05-018-022.R.Vasudevan and J.D. Smith are with the Department of Electrical Engineering, University of Southern California, Los Angeles, California. —R.Vasudevan is on leave of absence from the Institute of Mathematical Sciences, Madras, India.A.V. Phatak is now with Systems Control, Inc. in Palo Alto, California.  相似文献   
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5.
Conclusion  PEG-400, polysorbate 80, and 2 CDs (Trappsol HPB and Captisol) were used in an attempt to improve the aqueous solubility of a model hydrophobic drug, progesterone. The aqueous solubility of progesterone improved significantly from 0.007 mg/mL by the addition of PEG-400, CDs, and polysorbate 80. In systems containing various amounts of PEG-400 and 3% Trappsol HPB in water (% wt/wt), the theoretical solubility was calculated by adding the solubilities in the individual systems. The observed solubility values were up to 96% higher than the theoretical values. The effect of synergism was significant in 5% to 50% PEG-400/water systems containing Trappsol HPB. Systems containing Captisol did not show such synergistic effects. In general, the addition of polysorbate 80 to the PEG-400/water systems containing CDs affected synergism negatively.  相似文献   
6.
Chaudhary AA  Hemant  Mohsin M  Ahmad A 《Protoplasma》2012,249(2):417-422
In this study, loop-mediated isothermal amplification (LAMP)-based molecular marker was developed for authentication of Catharanthus roseus, a medicinal plant. Samples of this plant were collected from different geographical locations in India. Random amplified polymorphic deoxyribonucleic acid (DNA) analysis of collected samples was carried out with 25 random primers. A 610-bp DNA fragment, common to all accessions, was eluted, cloned, and sequenced. Four LAMP primers were designed on the basis of sequence of 610 bp DNA fragment. LAMP reaction, containing 10× Bst DNA polymerase reaction buffer, Bst DNA polymerase, four in-house designed primers, dNTPs, MgSO4, and betaine, was incubated at 65°C for 1 h. The resulting amplicon was visualized by adding SYBR Green I to the reaction tube. The data showed confirmatory results. Since the assay method is simple, sensitive, and cost-effective, it is a feasible method for identifying and authentication of C. roseus.  相似文献   
7.
Safe and eco-friendly alternatives to currently used hazardous chemico-physical methods of silver nanoparticles (AgNPs) synthesis are need of time. Rapid, low cost, selective detection of toxic metals in environmental sample is important to take safety action. Toxicity assessment of engineered AgNPs is essential to avoid its side effects on human and non-target organisms. In the present study, biologically active latex from Euphorbia heterophylla (Poinsettia) was utilized for synthesis of AgNPs. AgNPs was of spherical shape and narrow size range (20–50 nm). Occurrence of elemental silver and crystalline nature of AgNPs was analyzed. Role of latex metabolites in reduction and stabilization of AgNPs was analyzed by FT-IR, protein coagulation test and phytochemical analysis. Latex-synthesized AgNPs showed potential in selective and sensitive detection of toxic mercury ions (Hg2+) with limit of detection around 100 ppb. Addition of Hg2+ showed marked deviation in color and surface plasmon resonance spectra of AgNPs. Toxicity studies on aquatic non-target species Daphnia magna showed that latex-synthesized AgNPs (20.66 ± 1.52 % immobilization) were comparatively very less toxic than chemically synthesized AgNPs (51.66 ± 1.52 % immobilization). Similarly, comparative toxicity study on human red blood cells showed lower hemolysis (4.46 ± 0.01 %) by latex-synthesized AgNPs as compared to chemically synthesized AgNPs causing 6.14 ± 0.01 % hemolysis.  相似文献   
8.
Plasmonics - In this paper, focus is on the light trapping surface in crystalline silicon (c-Si) solar cells where thinner c-Si wafers are expected to be used by industry to reduce the cost of cell...  相似文献   
9.

Objectives

To determine, in areas supported by BRAC, Bangladesh i) the pre-diagnosis and pre-treatment attrition among presumptive and confirmed Multi-Drug Resistant Tuberculosis (MDR-TB) patients and ii) factors associated with attrition.

Methods

This was a retrospective cohort study involving record review. Presumptive MDR-TB patients from peripheral microscopy centres serving 60% of the total population of Bangladesh were included in the study. Attrition and turnaround time for MDR-TB diagnosis by Xpert MTB/RIF and treatment initiation were calculated between July 2012 and June 2014.

Results

Of 836 presumptive MDR-TB patients referred from 398 peripheral microscopy centres, 161 MDR-TB patients were diagnosed. The number of diagnosed MDR-TB patients was less than country estimates of MDR-TB patients (2000 cases) during the study period. Among those referred, pre-diagnosis and pre-treatment attrition was 17% and 21% respectively. Median turnaround time for MDR-TB testing, result receipt and treatment initiation was four, zero and five days respectively. Farmers (RR=2.3, p=0.01) and daily wage laborers (RR=2.1, p=0.04) had twice the risk of having pre-diagnosis attrition. Poor record-keeping and unreliable upkeep of presumptive MDR-TB patient databases were identified as challenges at the peripheral microscopy centres.

Conclusion

There was a low proportion of pre-diagnosis and pre-treatment attrition in patients with presumptive and confirmed MDR-TB under programmatic conditions. However, the recording and reporting system did not detect all presumptive MDR-TB patients, highlighting the need to improve the system in order to prevent morbidity, mortality and transmission of MDR-TB in the community.  相似文献   
10.
Varma H  Skildum AJ  Conrad SE 《PloS one》2007,2(12):e1256
Estrogens are required for the proliferation of hormone dependent breast cancer cells, making estrogen receptor (ER) positive tumors amenable to endocrine therapies such as antiestrogens. However, resistance to these agents remains a significant cause of treatment failure. We previously demonstrated that inactivation of the retinoblastoma protein (pRb) family tumor suppressors causes antiestrogen resistance in MCF-7 cells, a widely studied model of estrogen responsive human breast cancers. In this study, we investigate the mechanism by which pRb inactivation leads to antiestrogen resistance. Cdk4 and cdk2 are two key cell cycle regulators that can phosphorylate and inactivate pRb, therefore we tested whether these kinases are required in cells lacking pRb function. pRb family members were inactivated in MCF-7 cells by expressing polyomavirus large tumor antigen (PyLT), and cdk activity was inhibited using the cdk inhibitors p16(INK4A) and p21(Waf1/Cip1). Cdk4 activity was no longer required in cells lacking functional pRb, while cdk2 activity was required for proliferation in both the presence and absence of pRb function. Using inducible PyLT cell lines, we further demonstrated that pRb inactivation leads to increased cyclin A expression, cdk2 activation and proliferation in antiestrogen arrested cells. These results demonstrate that antiestrogens do not inhibit cdk2 activity or proliferation of MCF-7 cells in the absence of pRb family function, and suggest that antiestrogen resistant breast cancer cells resulting from pRb pathway inactivation would be susceptible to therapies that target cdk2.  相似文献   
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