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101.
Sustainable extraction of non-timber forest products (NTFPs) depends upon harvesting a small fraction of the total productivity. Over-exploitation can lead to a loss of biodiversity, but a low level of extraction, without value addition at the point of origin, is usually not economically feasible for extractors. Extraction and productivity levels per unit area for most non-timber forest products are unknown, nor do we have much information about value addition at various points in the marketing channels. Here we determine extraction and productivity levels for Amla trees (Phyllanthus emblica), which yield fruits that are used for a wide variety of purposes in preparation of various foods, beverages and medicines. We also present preliminary data on the price appreciation of the fruit for one of the processed products. We have determined that the current level of extraction, 60-80% of all fruits at the population level, may have a negative effect on new recruitment. We present a model for value addition that has the potential to enhance income and reduce the level of extraction. This model is currently being implemented by the Soliga community with the assistance of a non-governmental organization.  相似文献   
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103.
Plants are the primary producers of food for human being. Their intracellular environment alternation is influenced by abiotic stress factors such as drought, heat and soil salinity. Aeluropus lagopoides is a strong halophyte that grows with ease under high saline muddy banks of creeks of Gujarat, India. To study the response of salinity on metabolite changes in Aeluropus, three treatments, i.e. control, salinity and recovery, were selected for both shoot and root tissue. The cytosolic metabolite state was analysed by molecular chemical derivatization gas chromatography mass profiling. During saline treatment, significant increase of compatible solutes in shoot and root tissue was observed as compared to control. Subsequently, metabolic concentration decreased under recovery conditions. The metabolites like amino acids, organic acids and polyols were significantly detected in both shoot and root of Aeluropus under salinity. The metabolites like proline, aspartic acid, glycine, succinic acid and glycolic acid were significantly upregulated under stress. The salicylic acid was found to play a role in maintaining the polyols level by its down-regulation during salinity. The principle component analysis of all detected metabolites in both shoot and root showed that metabolites expressed under salinity (component 1) were highly variable, while metabolites expressed under recovery (component 2) were comparatively less variable as compared to control. The evolved intracellular compartmentalization of amino acids, organic acids and polyols in A. lagopoides can be a hallmark to sustaining at high salinity stress.  相似文献   
104.
These findings emphasize that the mTOR pathway may contribute to maintenance of quiescence of CSCs, and provide a basis for manipulating CSCs in the treatment of GBM. Future research should focus on further defining the PI3K/Akt/mTOR molecular network in the regulation of stem cell quiescence and provide rationale for targeting the cancer-initiating cells of GBM.  相似文献   
105.
In vitro models based on embryonic stem cells (ESC) are highly promising for improvement of predictive toxicology screening in humans. After the successful validation of embryonic stem cell test (EST) in 2001; concerns have been raised on the usage of mouse ESC and also the morphological evaluation of beating cell clusters. This requires specialized skill-sets and is highly prone to misjudgement and false positive results. To overcome these limitations, we undertook the present study incorporating improvisations over the conventional EST. Here, we explored the potential of a human ESC (hESC)-based assay to evaluate the potential toxicity of penicillin-G, caffeine, and hydroxyurea. Drug treatment inhibited hESC adhesion and substantially altered the morphology and viability (~ 50%) of embryoid bodies (EBs). Flow cytometry analysis not only showed a significant increase of apoptotic cells in the highest doses but also induced a diverse pattern in DNA content and cell cycle distribution relative to control. Both semi-quantitative and quantitative RT-PCR studies revealed a selective down regulation of markers associated with stemness (Nanog, Rex1, SOX-2, and hTERT); cardiac mesoderm (Cripto1, MEF-2C, and Brachyury); hepatic endoderm (AFP, HNF-3β, HNF-4α, GATA-4, and SOX-17); and neuroectoderm (Nestin, SOX-1, NURR1, NEFH, Synaptophysin, TH, and Olig2) in a drug as well as dose dependent manner indicating abnormal differentiation. Furthermore, a decrease in the expression of AFP and GFAP proteins followed by a dose-dependent reduction in the levels of hCG-β, progesterone-II, and estradiol hormones was demonstrated by immunocytochemistry and ECLIA, respectively. This new and unique approach comprising of DNA cell cycle analysis, germ layer-specific marker expression and hormone levels as endpoints might offer a clinically relevant and commercially viable alternative for predicting in vivo developmental toxicity.  相似文献   
106.
A series of novel triazine-based small molecule inhibitors (IV) of inosine monophosphate dehydrogenase was prepared. The synthesis and the structure-activity relationships (SAR) derived from in vitro studies are described.  相似文献   
107.
SUMMARY:: Suprahepatic inferior vena caval (IVC) injuries are rare but carry nearly a 100% mortality rate. The main problem with its surgical management is the technical difficulty in draining the IVC during cardiopulmonary bypass. In this report, an efficient method of IVC drainage for repair of the IVC on cardiopulmonary bypass is described.  相似文献   
108.
The causal link between disparate tropomyosin (Tm) functions and the structural instability in Tm is unknown. To test the hypothesis that the structural instability in the central region of Tm modulates the function of the overlapping ends of contiguous Tm dimers, we used transgenic mice (TmDM) that expressed a mutant α-Tm in the heart; S229E and H276N substitutions induce structural instability in the central region and the overlapping ends of Tm, respectively. In addition, two mouse cardiac troponin T mutants (TnT1–44Δ and TnT45–74Δ) that have a divergent effect on the overlapping ends of Tm were employed. The S229E-induced instability in the central region of TmDM altered the overlapping ends of TmDM, thereby it negated the attenuating effect of H276N on Ca2+-activated maximal tension. The rate of cross-bridge detachment (g) decreased in TmDM+TnTWT and TmH276N+TnTWT fibers but increased in TmDM+TnT45–74Δ fibers; however, TnT45–74Δ did not alter g, demonstrating that S229E in TmDM had divergent effects on g. The S229E substitution in TmDM ablated the H276N-induced desensitization of myofilament Ca2+ sensitivity in TmDM+TnT1–44Δ fibers. To our knowledge, novel findings from this study show that the structural instability in the central region of Tm modifies cardiac contractile function via its effect on the overlapping ends of contiguous Tm.  相似文献   
109.
In the streptozotocin induced diabetic rats treated separately with aqueous, ethanol, acetone and chloroform extracts of the seeds of B. nigra, the increase in serum glucose value between 0 and 1 hr of glucose tolerance test (GTT) was the least (29 mg/dl) in aqueous extract treated animals while it was 54, 44 and 44 mg/dl with chloroform, acetone and ethanol extracts respectively. In further studies carried out with aqueous extract, the effective dose was found to be 200 mg/kg body weight in GTT. Administration of 200 mg/kg body weight of aqueous extract to diabetic animals daily once for one month brought down fasting serum glucose (FSG) levels while in the untreated group FSG remained at a higher value. In the treated animals the increase in glycosylated hemoglobin (HbA1c) and serum lipids was much less when compared with the levels in untreated diabetic controls. These findings suggest that further studies with the aqueous extract of B. nigra seeds on its antidiabetic activity would be useful.  相似文献   
110.
Pseudomonas alcaligenes was detected at a high concentration (10 9 -10 10 cells mL -1 ) in the haemolymph of some dead Oryctes rhinoceros grubs collected from its breeding sites in the three southern districts, viz. Alleppey, Quilon and Kottayam of Kerala State, India. In a laboratory colony maintained for production of Oryctes virus, an important biocontrol agent of this major coconut pest, approximately 52% of the grubs succumbed to septicaemia with similar symptoms. The bacterium was found to be a component of the gut microflora of healthy grubs. Occurrence of the viral infection naturally or when induced in the laboratory in the O. rhinoceros grubs, appeared to be one of the biotic stress factors for P.alcaligenes to become an opportunistic pathogen. A preponderance of this bacterial infection in field populations during the periods when natural viral infection in grubs was above average, agrees with this observation. This finding becomes significant as infection by the opportunistic bacterial pathogen, P. alcaligenes , reduces the production of Oryctes virus inoculum in nature and limits the field-perpetuation of this viral biocontrol agent.  相似文献   
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