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11.
There is an increasing understanding that forests and the forestry sector are key elements in poverty reduction strategies in Africa. However, issues of equity between various forest users are becoming a major challenge to environmental development, forest management and poverty reduction. This paper presents an analysis of household representatives' socio-economic determinants and other constraints on accessing forest products, based on data collected through a questionnaire survey of 1865 respondents in seven districts of the Sissili province, southern Burkina Faso. Three logistic regression models were developed to examine determinants of access to the forest for collecting fuelwood, grazing livestock and collecting non-timber forest products (NTFPs). The results showed that access to forest products is associated with individual characteristics. Age, ethnicity, occupation and sources of income were significant determinants of access to all types of forest products. Access to the forest for grazing livestock was further influenced by gender and household size, while access to NTFPs was influenced by gender, household size and education level of the respondents. The formal forest law that precludes grazing in the forest, and customary rules and regulations pertaining to land tenure, were reported to be serious constraints to forest access for women and migrant people. Understanding the factors influencing access to products from commonly-owned forest resources could form the basis for developing, modifying and targeting policy instruments that promote equitable access. Policies should particularly encourage the direct involvement of vulnerable and marginalized groups (women and migrants) in forest management activities.  相似文献   
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Several species of red algae (Rhodophyta) from the coastal regions of Madagascar have been investigated for their natural products. The most abundant compound was cholesterol (5) in combination with a series of oxidized congeners. The brominated indoles 1–3 along with the sesquiterpene debilone (4) have been isolated from Laurencia complanata. For the first time, debilone (4) has been obtained from a marine plant. From the methanol extract of Calloseris sp., we have achieved the second isolation of the unusual A-ring contracted steroids (−)-2-ethoxycarbonyl-2β-hydroxy-A-nor-cholest-5-en-4-one (9) and phorbasterone B (10). The crude extracts of Laurencia complanata exhibited antimicrobial activity against Bacillus cereus, Staphylococcus aureus, Streptococcus pneumoniae, and Candida albicans.  相似文献   
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This study examines variations in the performance of partic-ipatory forest management programs among four forest management groups (FMGs) in southern Burkina Faso, and assesses the factors that influence their members’ perceptions of performance through a house-hold survey of 216 members. Variations in performance scores among the FMGs were analyzed through multivariate analysis of variance while multinomial regression analysis was used to identify factors that influ-ence their perception of the performance. The results reveal significant differences in performance scores among FMGs. Members of some FMGs perceived that the participatory forest management program ena-bled them to get benefits from the sale of fuelwood while performance scores in the forest conservation and decision-making processes is gener-ally poor. The score for economic performance of FMGs in turn was related to better access to roads and markets. Group size tended to en-hance economic performance via its strong influence on annual fuelwood harvest, while the resource base appeared to be inconsequential. Mem-bers of the forest management groups perceived that large group size and group heterogeneity, particularly in terms of ethnicity, as well as knowledge and awareness of problems related to the forest environment have no influence on the performance of their respective groups. For rural communities to have a favorable disposition toward sustainable forest management, differences in member understanding of collective actions and their impact before and during the implementation of partic-ipatory forest management programs should be considered.  相似文献   
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Preureteral vena cava (circumcaval ureter, retrocaval ureter) occurs in a third of the feline population and has been associated with ureteral strictures in humans. The aim of this retrospective cross‐sectional study was to describe the contrast‐enhanced multidetector row computed tomographic (MDCT) characteristics of presumed preureteral vena cava in a group of cats. Medical records from two institutions located in different continents were searched from 2010–2013 for cases with complete contrast‐enhanced MDCT examinations of the abdomen (i.e. included the entire course of the ureters and prerenal and renal segments of the caudal vena cava) and a diagnosis of preureteral caudal vena cava. For cases meeting inclusion criteria, CT scan data were retrieved and characteristics of the preureteral caudal vena cava were recorded. Presence of concomitant renal or ureteral diseases was also recorded. A total of 272 cats had contrast‐enhanced abdominal CT scans during the study period and of these, 68 cats (22.43 ± 4.96%) had a diagnosis of presumed preureteral vena cava. In all affected cats, a “reverse‐J ureter” was observed, i.e. a ureter running medially at the level of L4–5, passing dorsally to the caudal vena cava and then exiting ventrally between the caudal vena cava and aorta returning to its normal position. Having a preureteral vena cava resulted in an increased risk for concurrent urinary signs (OR = 3.00; CI: 95%; 1.28–6.99; P = 0.01). Findings supported the use of contrast‐enhanced MDCT for characterizing morphology of preureteral vena cava and its relation with ureters in cats.  相似文献   
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Our aim was to evaluate the influence of glucocorticoids on the adrenal gland using ultrasonography. Eleven healthy beagles were used in a prospective placebo-controlled study. All dogs received hydrocortisone at 10 mg/kg twice a day per os for 4 months or a gelatin capsule twice a day per os as a placebo. Clinical and endocrinologic examination of the dogs and ultrasonographic evaluation of adrenal echogenicity, shape, and measurement of the length and height of the cranial and caudal pole were performed at baseline (TO), at 1 (T1) and 4 months (T4) after the beginning of treatment, and 2 months after the end of the treatment including 1 month of tapering and 1 month without treatment (T6). The dogs were assigned randomly to the glucocorticoid (n = 6) and placebo groups (n = 5). At T1, the difference between the two groups for the height of the cranial and caudal pole was not ultrasonographically remarkable despite a statistically significant difference (P = 0.0165 and P = 0.0206). Decreased height and length of entire gland were observed at T4 (P < 0.0001, P = 0.0015, and P = 0.0035, respectively). Percentages of atrophy were variable between dogs. Both adrenal glands regained normal size and shape 1 month after cessation of glucocorticoid administration. As not all dogs developed marked adrenal gland atrophy and the degree of atrophy varied widely between individuals, ultrasonography cannot be the technique of choice to detect iatrogenic hypercortisolism. Ultrasonographic changes are reversible within 1 month after the end of glucocorticoid administration.  相似文献   
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Two adult male castrated dogs were evaluated for progressive paraparesis and ataxia. Neurologic examination showed severe ataxia, delayed proprioceptive placement in the pelvic limbs, pain upon palpation of the lumbar spine as well as facial paresis in one dog, and decreased withdrawal reflex of the pelvic limbs in the other dog. Magnetic resonance imaging (MRI) in both dogs showed diffuse meningeal and intramedullary lesions. However, no evidence of a mass was found. Biopsies could not be performed safely due to the location of the lesions. Cerebrospinal fluid (CSF) examination revealed an inflammatory pleocytosis associated with increased protein concentration and numerous large atypical round cells, often multinucleated. Nuclear fragmentation, micronuclei, and rare atypical mitoses were observed. Immunocytochemistry revealed CD1+ and CD11c+ staining, which, in concert with the morphology confirmed the diagnosis of histiocytic sarcoma (HS). Euthanasia was elected due to poor prognosis. Histopathologic examination showed diffuse spinal and meningeal infiltration with CD18+ neoplastic cells, without any evidence of mass formation, which completed the diagnosis of diffuse leptomeningeal HS involving the brain and the spinal cord. Canine central nervous system (CNS) HS has been seldom reported in the literature, with only isolated cases identified on CSF cytology. The cases reported here are remarkable in describing a diffuse CNS leptomeningeal HS associated with neoplastic cells in the CSF of dogs without a tumor mass. These cases emphasize the potential critical importance of CSF analysis in providing an antemortem diagnosis of neoplasia in neurologic patients.  相似文献   
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