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Surveys were conducted in the cold desert environment of the Lahaul valley in the northwestern Himalaya for assessing the past and present status of Kuth (Saussurea lappa) cultivation. The findings reveal that this age-old practice now is in bottleneck. Main factors responsible for this setback to the species were the lengthy cultivation cycle, small land holdings, and even fluctuating and relatively low market prices. Owing to these constraints farmers have now started replacing cultivation of this threatened herb with pea (Pisum sativum L.), potato (Solanum tuberosum L.) and hop (Humulus lupulus L.). These crops obtained popularity due to comparatively more economic returns as well as their easy adaptability to the short growth season of the cold desert environment. Kuth cultivation in this region is among the interesting examples of domesticating wild medicinal herb by some innovative farmers during the 1920s. However, in the recent past farmers have been less interested to continue this practice due to its larger cultivation cycle, more profits with cash crops like pea and potato, and permit formalities at the time of export from the valley. In addition to being the oldest cash crop in the cold desert environment, Kuth is an endangered medicinal herb that has to be conserved on a priority basis. This study attempts to find out potential measures such as regular revision of market rates, development of existing uncultivable land under medicinal plant cultivation and strengthening the marketing network through establishment of federations of farmers at village level to revive cultivation of this important species.  相似文献   
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Background  

The present paper describes a topological model of biofeedback. This model incorporates input from a sensory organ and a transduction phase mediated through catecholamine production in the feedback path. The transduction phase comprises both conservative and dissipative systems, from which the appropriate output is combined in a closed loop.  相似文献   
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Lata S  Piehler J 《Nature protocols》2006,1(4):2104-2109
This protocol describes the synthesis of a lipid-like molecule carrying a head group containing two nitrilotriacetic acid moieties. This multivalent chelator lipid can be incorporated into lipid membranes, to which histidine-tagged protein can then be tethered in an oriented fashion. Possible applications of this lipid are protein tethering to solid-supported membranes, to lipid vesicles or to live cells. As compared to conventional monovalent chelator lipids, this lipid can achieve highly stable tethering of proteins by the multivalent chelator head. The eight-step synthesis described in this protocol can be completed within 4-5 weeks.  相似文献   
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Treatment with C. mukul and O. sanctum, showed a significant decrease in cholesterol and triglyceride levels respectively. O. sanctum also significantly increased serum HDL-cholesterol compared to control. Serum MDA levels were significantly reduced in all the treated groups compared to control suggesting that each of the drugs under study were effective in their free radical scavenging action. Erythrocyte SOD activity was increased in all the treatment groups with C. mukul showing the maximum effect followed by O. sanctum, folic acid and ramipril. The erythrocyte CAT activity was significantly increased in all the drug treated groups with maximum increase seen in O. sanctum and ramipril treated groups, whereas lesser effects were observed with C. mukul and folic acid groups. Thus, the indigenous drugs, C. mukul and O. sanctum had beneficial effect on hypercholesterolemic rabbit model, both in terms of lipid profile as well as antioxidant potential. Ocimum sanctum was found to be the most promising of all the drugs. Moreover, it could be hypothesized that these plant products along with folic acid and ramipril can be explored for synergistic effect for treatment for hypercholesterolemic conditions.  相似文献   
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In presence of the glycosylation inhibitors, 2-deoxy-d-glucose (1 mg/ml), tunicamycin (30 μg/ml), 1-deoxynojirimycin (30 μg/ml) and d-glucono-δ-lactone (1 mg/ml), total cellobiase activity, in the extracellular, intracellular and cell bound fractions, of the fungus Termitomyces clypeatus grown in 20 ml cellobiose medium (1%, w/v) increased by 50-, 1.8-, 2.4-, 1.3-fold, respectively, with respect to control medium (16.3 U). The inhibitors also stimulated secretion of 95% of the total protein in culture medium, except d-glucono-δ-lactone which released 60% of the total protein. 2-Deoxy-d-glucose (1 mg/ml) led to production of extracellular cellobiase up to 40 U/ml, whereas in absence of the inhibitors only 0.59 U/ml enzyme was detected.  相似文献   
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Existing drugs for visceral leishmaniasis (VL) are partially effective, toxic, having high cost and long term treatment. Their efficacies are also compromised due to suppression of immune function associated during the course of infection. Combination therapy including a potential and safe immunostimulant with lower doses of effective drug has proven as a significant approach which is more effective than immunotherapy or drug therapy alone. In the present study, we have used the combination of Pam3Cys (an in-built immunoadjuvant and TLR2 ligand) and miltefosine. Initially dose optimization of both the agents was carried out and after that, antileishmanial effect of their combination was evaluated. All experiments were done in BALB/c mouse model. The immunomodulatory role of Pam3Cys on the immune functions of the host receiving combination treatment was also determined using immunological and biochemical parameters viz. phagocytosis, Th1/Th2 cytokines and production of ROS, RNS and H(2)O(2). Combination group showed significant enhancement in parasitic inhibition as compared to groups receiving miltefosine and Pam3Cys separately. Enhanced production of Th1 cytokines as well as ROS, RNS and H(2)O(2) was witnessed during the study of immunological alterations. Remarkable increase in phagocytosis index was also observed. Thus, the risk of development of drug resistance against miltefosine can be resolved through using low doses of it and Pam3Cys (single-dose) in combination and also provide a promising alternative for cure of leishmaniasis, with a pronounced transformation of the host immune response.  相似文献   
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