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Garnering support from local people is critical for maintaining ecologically viable and functional protected areas. However, empirical data illustrating local people’s awareness of the importance of nature’s services is limited; hence possibly impeding effective ecosystem (environmental)-services based conservation efforts. Using data from five protected forests in four developing Southeast Asian countries, we provide evidence that local people living near parks value a wide range of environmental services, including cultural, provisioning, and regulating services, provided by the forests. Local people with longer residency valued environmental services more. Educated as well as poor people valued forest ecosystem services more. Conservation education has some influence on people’s environmental awareness. For conservation endeavors to be successful, large-scale transmigration programs should be avoided and local people must be provided with alternative sustenance opportunities and basic education in addition to environmental outreach to reduce their reliance on protected forests and to enhance conservation support.  相似文献   
153.
A morroniside cinnamic acid conjugate was prepared and evaluated on E-selectin mediated cell–cell adhesion as an important role in inflammatory processes. 7-O-Cinnamoylmorroniside exhibited excellent anti-inflammatory activity (IC50 = 49.3 μM) by inhibiting the expression of E-selectin; further, it was more active than another cinnamic-acid-conjugated iridoid glycoside (harpagoside; IC50 = 88.2 μM), 7-O-methylmorroniside, and morroniside itself. As a result, 7-O-cinnamoylmorroniside was observed to be a potent inhibitor of TNF-α-induced E-selectin expression.  相似文献   
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The genomic structure of the pfoA-colA region in six theta-toxin-deficient strains of Clostridium perfringens was examined by Southern hybridization using the pfoR, pfoA, pbg, arcABDC and colA genes, encoding regulator for pfoA, theta-toxin, beta-galactosidase, arginine metabolism enzymes and kappa-toxin, respectively, as gene probes. It is suggested that the productivity of theta-toxin in these strains is diverse because of the multiple genetic backgrounds including single deletion of pfoA, large deletion of the pfoA-colA region and the putative point mutations.  相似文献   
157.
A novel enzyme, which was named Nα-benzyloxycarbonyl amino acid urethane hydrolase, was purified from a cell-free extract of Streptococcus faecalis R ATCC 8043, using Nα-benzyloxycarbonyl glycine as substrate. The enzyme was purified 1300-fold with an activity yield of 8%. The purified enzyme was homogeneous by disc electrophoresis. The molecular weight of the native enzyme is about 220,000 by gel filtration, and a molecular weight of 32,000 was determined for the reduced and denatured enzyme by gel electrophoresis in sodium dodecyl sulfate. The isoelectric point was 4.48. The enzyme was inhibited by p-chloromercuribenzoate. The presence of divalent cations (i.e., Co2+ or Zn2+) is essential for its activity.  相似文献   
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Angiogenesis is an essential component of skeletal development and VEGF signaling plays an important if not pivotal role in this process. Previous attempts to examine the roles of VEGF in vivo have been largely unsuccessful because deletion of even one VEGF allele leads to embryonic lethality before skeletal development is initiated. The availability of mice expressing only the VEGF120 isoform (which do survive to term) has offered an opportunity to explore the function of VEGF during embryonic skeletal development. Our study of these mice provides new in vivo evidence for multiple important roles of VEGF in both endochondral and intramembranous bone formation, as well as some insights into isoform-specific functions. There are two key differences in vascularization of developing bones between wild-type and VEGF(120/120) mice. VEGF(120/120) mice have not only a delayed recruitment of blood vessels into the perichondrium but also show delayed invasion of vessels into the primary ossification center, demonstrating a significant role of VEGF at both an early and late stage of cartilage vascularization. These findings are the basis for a two-step model of VEGF-controlled vascularization of the developing skeleton, a hypothesis that is supported by the new finding that VEGF is expressed robustly in the perichondrium and surrounding tissue of cartilage templates of future bones well before blood vessels appear in these regions. We also describe new in vivo evidence for a possible role of VEGF in chondrocyte maturation, and document that VEGF has a direct role in regulating osteoblastic activity based on in vivo evidence and organ culture experiments.  相似文献   
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Chromium was proposed to be an essential trace element over 50?years ago and has been accepted as an essential element for over 30?years. However, the studies on which chromium’s status are based are methodologically flawed. Whether chromium is an essential element has been examined for the first time in carefully controlled metal-free conditions using a series of purified diets containing various chromium contents. Male Zucker lean rats were housed in specially designed metal-free cages for 6?months and fed the AIN-93G diet with no added chromium in the mineral mix component of the diet, the standard AIN-93G diet, the standard AIN-93G diet supplemented with 200?μg?Cr/kg, or the standard AIN-93G diet supplemented with 1,000?μg?Cr/kg. The chromium content of the diet had no effect on body mass or food intake. Similarly, the chromium content of the diet had no effect on glucose levels in glucose tolerance or insulin tolerance tests. However, a distinct trend toward lower insulin levels under the curve after a glucose challenge was observed with increasing chromium content in the diet; rats on the supplemented AIN-93G diets had significantly lower areas (P?<?0.05) than rats on the low-chromium diet. The studies reveal that a diet with as little chromium as reasonably possible had no effect on body composition, glucose metabolism, or insulin sensitivity compared with a chromium-“sufficient??diet. Together with the results of other recent studies, these results clearly indicate that chromium can no longer be considered an essential element.  相似文献   
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