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531.
Despite growing interest in traditional and local ecological knowledge for conservation and resource management, the role of migrant resource users is largely unexplored. Challenging many assumptions about what constitutes “local knowledge,” migrant and immigrant harvesters of non-timber forest products on the Olympic Peninsula, Washington possess useful ecological knowledge of overstory–understory relationships and how forestry practices affect understory biological and commercial production. Harvesters of salal (Gaultheria shallon), a shrub used in the multi-million dollar floral greens industry, were interviewed in Mason County, Washington in 2001–2003. Interviews revealed that harvesters possess different kinds of resource management knowledge depending on whether they are experienced harvesters or more recent newcomers to the area. These differences may also correlate with differences in their harvesting practices. Understanding how resource management knowledge differs between experienced and newcomer harvesters can inform forest managers in their efforts to develop effective management and permitting policies for floral greens and other non-timber forest resources in the Pacific Northwest of the United States.
Heidi L. BallardEmail:
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532.
Because of its possible importance to the etiology of cystic fibrosis lung disease, the ion and water transport properties of tracheal epithelium were studied. Net liquid flux (J(V)) across porcine tracheal epithelium was measured in vitro using blue dextran as a volume probe. Luminal instillation of isosmotic sucrose solution (280 mM) induced a small net secretion of liquid (7.0 +/- 1.7 nl x cm(-2) x s(-1)), whereas luminal hyposmotic sucrose solutions (220 or 100 mM) induced substantial and significant (P < 0.05) liquid absorption (34.5 +/- 12 and 38.1 +/- 7.3 nl x cm(-2) x s(-1), respectively). When the luminal solution was normal (isosmotic) Krebs buffer, liquid was absorbed at 10.2 +/- 1.1 nl x cm(-2) x s(-1). Absorptive J(V) was abolished by 100 microM amiloride in the luminal solution and significantly reduced when the luminal solution was Na(+)-free Krebs solution. Absorptive J(V) was not significantly affected by 300 microM 5-nitro-2-(3-phenylpropylamino)benzoate or 100 microM diphenylamine-2-carboxylic acid, both cystic fibrosis transmembrane conductance regulator protein (CFTR) inhibitors, in the instillate but was significantly reduced by 60% when the luminal solution was Cl(-)-free Krebs solution. We conclude that water freely permeates porcine tracheal epithelium and that absorption of liquid is normally driven by active transcellular Na(+) transport and does not require the CFTR.  相似文献   
533.
534.
We induced beta-adrenergic receptor blockade at 28 days gestation in the fetal rabbit with an irreversible beta-antagonist, bromace-tylalprenolomenthane (BrAlp). There was a marked decrease in concentration of available receptors in lung with increasing doses of BrAlp. BrAlp treatment decreased isoproterenol, but not prostaglandin, stimulated adenosine 3',5'-cyclic monophosphate (cAMP) generation in lung minces, and had no effect on activation of adenylate cyclase through non-beta-receptor-mediated components of the cyclase system in particulate preparations. Phospholipid recovery via lung lavage was significantly less from treated fetuses than from controls in groups delivered by cesarean section at 30 days (-31%) or vaginally at 31 days (-34%) and not allowed to air breathe. However, if fetuses from either group were allowed to air breathe, the difference was abolished. BrAlp treatment did not affect the phospholipid composition in lavage fluid, the rate of phosphatidylcholine synthesis, or tissue content of total or saturated phosphatidylcholine. Beta-adrenergic receptor blockade did not produce a significant change in lung water content either at or after birth regardless of the route of delivery. These data indicate that endogenous catecholamines play a role in surfactant secretion in both the fetal and newborn rabbit. We found no effects of BrAlp treatment on lung water, suggesting perhaps a less important role of endogenous catecholamines or that fewer receptors are required for this response than remained after treatment.  相似文献   
535.
A primary genetic linkage map for human chromosome 12   总被引:20,自引:0,他引:20  
A primary genetic map for human chromosome 12 has been constructed from data on 23 restriction fragment length polymorphic systems collected in 38 normal families with large sibships. Linkage analysis of the genotypic data has ordered 16 loci into a continuous genetic map of 111 cM in males and 258 cM in females. Although most of the genetic map reflects a higher rate of recombination in females relative to males, significantly more frequent recombination was observed in males than in females in intervals between loci on the distal portion of the short arm of the chromosome. The mapping data shown here will serve as a first step toward a high-resolution genetic map for human chromosome 12.  相似文献   
536.
We have measured growth factor concentrations in human milk from mothers of term and premature infants to identify any adaptive responses to premature delivery. Measurements included concentrations of epidermal growth factor and insulin and the growth-promoting activity of milk in vitro, estimated by the stimulation of rats of protein accumulation in cultured human fibroblasts. Compared with women delivering at full-term, mothers of premature infants produced milk containing higher concentrations of epidermal growth factor and increased growth-promoting activity in vitro, changes which were probably maintained throughout lactation. The anabolic effect of human milk in cultured human fibroblasts could be attributed partially but not entirely to epidermal growth factor, suggesting that the concentrations of additional growth factors were also increased following premature delivery. Insulin did not contribute to the extra growth-promoting activity; premature delivery depressed the insulin concentration significantly on the first two days of lactation and, thereafter, milk from mothers of term or premature infants contained similar amounts of insulin. Growth factor concentrations were also measured in cow's milk-based formulae. These formulae contained low concentrations of epidermal growth factor and insulin and reduced growth-promoting activity compared with human milk. Changes in milk growth factor concentrations may occur as a compensatory mechanism to accelerate growth and development in pre-term infants, and if so, it follows that premature infants could benefit more from their own mother's milk than from pooled human milk or from cow's milk-based formulae.  相似文献   
537.
High-voltage electrical injury: chronic wound evolution   总被引:2,自引:0,他引:2  
A chronic electrical burn model employing documentary and diagnostic techniques was designed in the primate for investigating wound evolution up to 10 days after injury. A standardized 40-kJ, 3500-V, 4.2-A, 2.5-s bilateral, symmetrical upper extremity electrical injury was performed. Gross observation studies documented tissue injury extending more proximally on the deep surfaces of individual muscles and between muscle layers. Specific regions, or "choke" points, in the forearm exist in which decreased cross-sectional areas and highly resistant tissue composition resulted in increased heat production and more severe tissue damage. Muscle injury was analyzed using light microscopy, revealing patchy cellular necrosis intermixed with viable cells. Digital subtraction angiography demonstrated segmental narrowing and "pruning" of large vascular trunks with a significant decrease in nutrient vessels in affected areas. Ulnar nerve conduction studies showed loss of conduction proximal to the cubital fossa with no recovery. Although characteristic patterns of injury were documented in skin, muscle, vessels, and nerves, no experimental evidence was found for progressive necrosis.  相似文献   
538.
The molybdenum centre of respiratory nitrate reductase from Paracoccus denitrificans has been investigated by e.p.r. spectroscopy of Mo(V). In common with the centres of the analogous enzymes from Escherichia coli and Pseudomonas aeruginosa, it undergoes a pH- and anion-dependent transition between two different e.p.r. signal-giving species. Comparison of the relevant e.p.r. parameters extracted with the help of computer simulations reveals ligation of the metal in the active centres of the three enzymes to be identical.  相似文献   
539.
1. Competitive binding and receptor cross-linking experiments have been used to examine the receptor-ligand interactions between three bovine insulin-like growth factors (IGF) and monolayer cultures of myoblasts and fibroblasts. 2. Labelled IGF-2 bound predominantly to the type 2 receptor with negligible label cross-linked to the type 1 receptor, notwithstanding the ability of IGF-2 to compete effectively for the binding of IGF-1 to the type 1 receptor. Approx. 100-fold higher concentrations of IGF-1 or the N-terminal truncated (des-Gly-Pro-Glu) IGF-1 (-3N:IGF-1) were required to produce competition equivalent to IGF-2. 3. All IGF peptides, but especially IGF-1, enhanced the binding of labelled IGF-2 to the type 2 receptor of lung fibroblasts. This unusual effect was probably a consequence of the displacement of labelled IGF-2 otherwise bound to a medium protein, a conclusion supported by the demonstration of a 38 kDa membrane protein cross-linked to labelled IGF-2. 4. Both IGF-1 and -3N:IGF-1 bound only to the type 1 IGF receptor in L6 myoblasts, rat vascular smooth-muscle cells and human lung fibroblasts. The peptides competed for labelled IGF-1 binding with potencies in the order -3N:IGF-1 greater than IGF-1 greater than IGF-2 much greater than insulin. Since the IGF peptides were equipotent in skin fibroblasts, it was proposed that the apparently higher affinity of -3N:IGF-1 for receptors in the other cell types was instead a consequence of a low affinity of this peptide for the competing 38 kDa binding protein.  相似文献   
540.
Serum samples were collected from 116 wolves which were captured in southcentral Alaska during 1975 through 1982. Antibodies to the following infectious disease agents were found: infectious canine hepatitis virus-72 of 87 (81%), canine parvovirus type 2-0 of 55 (0%) through 1979 and 10 of 32 (31%) after 1979, Francisella tularensis-16 of 67 (25%), canine distemper virus-10 of 83 (12%), Coxiella burnetti-5 of 95 (5%), rabies virus-1 of 88 (1%), Brucella spp.-1 of 67 (1%), Leptospira interrogans-1 of 82 (1%). Apparently rabies, brucellosis, and leptospirosis were rare and had little effect on the wolf population. Conversely, the other five infections were comparatively common and may have had a negative impact on the health of specific individual wolves, but did not appear to influence the health of the population.  相似文献   
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