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211.
This paper presents findings from a representative opinion poll among Swiss private forest owners regarding the actual and
future role of outside professional advice, training and extension services. First, the Swiss private forest owners are a
highly heterogeneous group insofar as they are difficult addressees for any form of public support and extension services.
Second, the majority of Swiss private forest owners appreciate the presently offered training facilities as well as the advisory
activities of the cantonal and communal public forest services. Third, Swiss private forest owners are open to new forms of
extension provided that such services will be custom-tailored and initiated by the advisers. Custom-tailored in this context
means that the individual demands of private forest owners need to be addressed in a differentiated manner and advice will
not be limited to the economic aspects of timber production. Local advisers from cantonal and communal forest services are
presently in a pole position for offering new forms of extension, however, there are also more opportunities for services
offered by private firms and non-governmental organisations. The broader scope for advisory and supporting activities as well
as an increasing variety of potential actors providing such services implies a change in formulating and implementing forest
policy programs at federal and cantonal levels. 相似文献
212.
213.
AIM: To study factors affecting the stability of nylon monofilament for intraluminal middle cerebral artery occlusion in rats.METHODS:Successful rates and infarct volume of ischemic model were compared by polyvinyl alcohol (PVA) coated and silicon coated nylon monofilament intraluminal occlusion of middle cerebral artery under condition of ligation and without ligation of peterygopalatine artery.RESULTS:The successful rates were 60% and 53% in two groups under condition of ligation of peterygopalatine artery, and 20% and 27% in other two groups under condition of without ligation of peterygopalatine artery respectively. The intracranial length of nylon monofilament were about 7 mm in successful model and 4 mm in failure model. Animals in the PVA coated nylon monofilament group showed neurological dificit signs earlier, and had a significantly larger infarct volume at 12 hours of ischemia than those in the silicon coated group.CONCLUSIONS:The ligation of peterygopalatine artery is critical in the success of making this kind of ischemic model. The appropriate position of nylon monofilament entering crania and the good expansibility of PVA play an important role in occlusion of blood flow. Because of the relatively lower successful rate, a new substitute with unique quality, proper hardness and better elasticity needs to be explored in the future. 相似文献
214.
HAN Jin-an KUANG Yong-qin ZHOU Hu-tian YANG Li-bing ZENG Fan-jun SUN Zeng-hui HUWei-yi WANG Xiao-li 《园艺学报》2000,16(3):269-271
AIM: To study the protective effect of panax notoginseng saponins (PNS) on brain in experimental brain injury. RESULTS:The MDA in the brain tissue following brain injury significantly increased, which related to the degree of brain edema; PNS dramatically decreased MDA in the brain tissue following brain injury and can alleviate the neuron ultrastructures damage.CONCLUSION:The inhibition of injury induced MDA increasing in the brain tissue by PNS may contribute to its overall neuroprotective action. 相似文献
215.
Neuronal growth associated protein (GAP-43) is a membrane bound phosphoprotein found in the axonal growth cones of sprouting central nervous system axons. It is neuron specific and is proposed to play a critical role in growth cone function during development of the nervous system or the regenerative recovery from axon injury. The injury leads to the transfection of fibroblasts with the GAP-43 gene, which result in increasing GAP-43 expression. GAP-43 is expressed at high levels during the course of recovery of brain injury. GAP-43 acts with calmodulin and G protein to regulate metabolic responses that initates axonal growth. It is important to reestablish neuronal structure and axonal sprouting. The level of GAP-43 returns to basal level once sprouting has finished. So more and more researchers attach importance to the study of GAP-43, which will improve the level of treatment with brain injury. 相似文献
216.
基因打靶与体细胞克隆技术制备乳腺生物反应器的研究进展 总被引:1,自引:1,他引:0
在动物乳腺生物反应器研究中,传统方法不可避免地造成基因表达调控元件的人工拼接和外源基因在动物基因组中随机整合所带来的“位置效应”,致使转基因动物外源基因的表达水平不高且差异较大。而基因打靶在外源基因定点整合、消除位点效应方面具有明显优势。体细胞核移植技术可以提前在细胞水平对转基因动物进行筛选,不但可以节省时间,更降低了制备乳腺生物反应器的成本。作者简述了基因打靶与体细胞核移植技术结合制备乳腺生物反应器的优越性、存在问题、解决办法及其应用前景和展望。 相似文献
217.
218.
AIM:To explore the main risk factors of diabetic encephalopathy and to investigate the changes of mitochondria in early-onset type 1 diabetes. METHODS:Single dose of streptozotocin was injected through the femoral vein to establish type 1 diabetes model in rats. The levels of glucose, triglyceride and cholesterol in plasma, cerebrospinal fluid and cerebral cortex were measured. Oxidative and antioxidative status was evaluated by determining the levels of malondialdehyde and glutathione in the isolated mitochondria of cerebral cortex. Furthermore, the level of active AMP-activated protein kinase(AMPK) in the isolated mitochondria was detected by Western blotting. Degenerative neurons were identified by Fluo-Jade-C staining in serial brain sections. Autophagy-lysosome was observed under electron microscope. RESULTS:The main risk factor in the development of diabetic encephalopathy was hyperglucemia, which increased the Fluo-Jade-C positive neurons in the cerebral cortex of diabetic rats. The content of malondialdehyde was increased and glutathione was decreased in diabetic rats compared with the control animals. The activity of AMPK was lower in diabetic brain than that in normal brain. Aggregated autophagysome and mitochondria enveloped by autophagy-lysosome were observed in pyramidal cells of cerebral cortex in diabetic rats. CONCLUSION:Persistent hyperglycemia and mitochondrial dysfunction contribute to the diabetic encephalopathy at an early stage in type 1 diabetes, indicating that the mechanism may be partly related to the oxidative stress and activation of autophagy. 相似文献
219.
During the past decade the development and adoption of transgenic technology has progressed rapidly. In 2007, biotech crops
were grown by 12 million farmers in 23 countries covering 114.3 million hectares. This progress can be attributed to developments
in molecular genetics, plant transformation and regeneration techniques and a better understanding of the underlying processes
involved in DNA recombination. While almost every significant crop species has been successfully transformed, in many species
the development of rapid, highly efficient, and routine transformation systems is still in progress. The commonly-used methods
along with some promising alternative methods of plant transformation are described here. Achievements and future prospect
in the areas of developing biotic and abiotic stress-tolerant crop varieties and progress in incorporating nutritional and
other useful qualities into plants are also discussed in this paper. 相似文献
220.
MacDonald KA Kittleson MD Larson RF Kass P Klose T Wisner ER 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》2006,20(5):1093-1105
BACKGROUND: Hypertrophic cardiomyopathy (HCM) is the most common heart disease of cats, resulting in left ventricular (LV) hypertrophy, myocardial fibrosis, and diastolic dysfunction. HYPOTHESIS: Ramipril will reduce LV mass, improve diastolic function, and reduce myocardial fibrosis in cats with HCM without congestive heart failure (CHF). ANIMALS: This prospective, blinded, placebo-controlled study included 26 Maine Coon and Maine Coon cross-bred cats with familial HCM but without CHF. METHODS: Cats were matched for LV mass index (LVMI) and were randomized to receive ramipril (0.5 mg/kg) or placebo q24h for 1 year, with investigators blinded. Plasma brain natriuretic peptide (BNP) concentration, plasma aldosterone concentration, Doppler tissue imaging (DTI), and systolic blood pressure were measured at baseline and every 3 months for 1 year. Cardiac magnetic resonance imaging (cMRI) was performed to quantify LV mass and myocardial fibrosis by delayed enhancement (DE) cMRI at baseline and 6 and 12 months. Plasma angiotensin-converting enzyme (ACE) activity was measured on 16 cats 1 hour after PO administration. RESULTS: Plasma ACE activity was adequately suppressed (97%) in cats treated with ramipril. LV mass, LVMI, DTI, DE, blood pressure, plasma BNP, and plasma aldosterone were not different in cats treated with ramipril compared with placebo (P = .85, P = .94, P = .91, P = .89, P = .28, P = .18, and P = .25, respectively). CONCLUSION: Treatment of Maine Coon cats with HCM without CHF with ramipril did not change LV mass, improve diastolic function, alter DE, or alter plasma BNP or aldosterone concentrations in a relevant manner. 相似文献