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Invasion by the Australian paperbark, Melaleuca quinquenervia, has degraded large areas of south Florida wetlands. Restoration of these wetlands requires the removal of expansive monocultures of this large tree while simultaneously curtailing its spread. Management strategies developed by federal and state agencies include biological control to halt the spread of this species and to prevent reinfestation of cleared areas. This requires biological agents able to reduce flowering, seed production, and growth while increasing mortality of seedlings and saplings. Two of the three introduced agents (Oxyops vitiosa Pascoe and Boreioglycaspis melaleucae Moore) partially meet these needs but outcomes are not spatially or temporally consistent. Thus, additional agents are needed. The bud-gall fly Fergusonina turneri Taylor, with its mutualistic nematode Fergusobia quinquenerviae Davies and Giblin-Davis, is actively being released but has not established. A fourth promising agent, the gall midge Lophodiplosis trifida Gagné, manifested an extremely narrow host range during laboratory testing. Oviposition was indiscriminant in caged environments. Small, incipient, unilocular galls were initiated on Melaleuca viminalis, but larval development ensued only on M. quinquenervia. The unilocular galls on M. viminalis did not grow and produced no adult flies. As a result, M. viminalis test plants suffered only minor cosmetic damage. Observations from both Australia and Florida attest to the ability of this midge to impede M. quinquenervia growth and kill small plants. Thus, L. trifida is safe to release and will likely contribute to management objectives for control of this pernicious wetland invader.  相似文献   
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Arıcı OF  Cetin N 《Regulatory peptides》2011,166(1-3):139-142
Recent data indicate that ghrelin has protective effects in different organs and cell types including the pancreas, heart, and gastrointestinal tract. The purpose of this study was to determine whether ghrelin plays a protective role against CCl4-induced coagulation disturbances in rats.Fourty male Sprague–Dawley rats were equally divided into four groups including group 1 (1 ml physiological saline s.c., for 5 days), group 2 (CCl4, i.p., single dose of 1.6 g/kg), group 3 (ghrelin, s.c., 10 nmol/kg/day, for 5 days) and group 4 (ghrelin, 10 nmol/kg/day, for 5 days plus CCl4, i.p., single dose of 1.6 g/kg on the 5th day). Fibrinogen level, activated partial thromboplastin time (aPTT), prothrombin time (PT), platelet counts and alanine transaminase (ALT) activity were evaluated. The values of PT, aPTT and ALT activity were increased (p < 0.05), while fibrinogen level was decreased (p < 0.05) due to CCl4 treatment alone. Pre-treatment with ghrelin prior to the administration of CCl4 reduced (p < 0.05) PT, aPTT and ALT values and increased (p < 0.05) fibrinogen level when compared with CCl4-treated only group. The results of this study suggest that exogenously administered ghrelin may play a protective role against CCl4-induced coagulation disturbances in rats.  相似文献   
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In this study we investigated whether pretreatment with melatonin was protective against the injury of the central nervous system (CNS) in rats receiving LD(50) whole body irradiation. The wistar rats were randomized into four groups: i) the control group (CG), ii) melatonin-administered group (MG; 1 mg/kg body weight), iii) irradiated group (RG; 6.75 Gy, one dose), and iv) melatonin-administered and irradiated group (MRG). Blood samples were drawn from the rats 24 h after the treatment and plasma glutathione levels were assayed. Plasma glutathione level was significantly higher in RG than CG. The melatonin pretreatment prevented GSH increase induced by irradiation. Lipid peroxidation and glutathione levels of rat cerebral cortex were determined in all groups after 24 h. Cortical malondialdehyde (MDA) was significantly higher in the RG. The melatonin pretreatment prevented cortical MDA increase induced by irradiation. Cortical GSH was significantly lower in RG than the CG. The melatonin pretreatment prevented cortical GSH decrease induced by irradiation. Tissue samples were obtained from cerebral cortex and hypothalamus which also were affected by ionizing irradiation in the CNS and were evaluated with electron microscopy. Histopathological findings showed that LD(50) whole body irradiation resulted in damage of the neuronal cells of CNS. The results obtained from this study demonstrated that pretreatment with melatonin prevented the damage that develops in CNS following irradiation. The beneficial effect of melatonin can be related to protection of the CNS from oxidative injury and preventing the decrease in the level of cortical glutathione.  相似文献   
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中国四瘿螨属一新种记述(蜱螨亚纲,瘿螨科)   总被引:1,自引:0,他引:1  
记述瘿螨科Eriophyidae、叶刺瘿螨亚科Phyllocoptinae四瘿螨属Tetra 1新种,即石河子四瘿螨Tetra shiheziensis sp.nov.寄主为杨树Populus sp.(Salicaceae),分布新疆石河子市.  相似文献   
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In the wild, primate foraging behaviors are related to the diversity and nutritional properties of food, which are affected by seasonal variation. The goal of environmental enrichment is to stimulate captive animals to exhibit similar foraging behavior of their wild counterparts, e.g. To extend foraging time. We conducted a 12-month study on the foraging behavior of Japanese macaques in a semi-naturally forested enclosure to understand how they use both provisioned foods and naturally available plant foods and what are the nutritional criteria of their consumption of natural plants. We recorded time spent feeding on provisioned and natural plant foods and collected the plant parts ingested of their major plant food species monthly, when available.We conducted nutritional analysis (crude protein, crude lipid, neutral detergent fiber-'NDF', ash) and calculated total non-slructural carbohydrate - 'TNC' and total energy of those food items. Monkeys spent 47% of their feeding time foraging on natural plant species. The consumption of plant parts varied significantly across seasons. We found that leaf items were consumed in months when crude protein, crude protein-to-NDF ratio, TNC and total energy were significantly higher and NDF was significantly lower, fruit/nut items in months when crude protein and TNC were significantly higher and crude lipid content was significantly lower, and bark items in months when TNC and total energy were higher and crude lipid content was lower. This preliminary investigation showed that the forested enclosure allowed troop members to more fully express their species typical flexible behavior by challenging them to adjust their foraging behavior to seasonal changes of plant item diversity and nutritional content, also providing the possibility for individuals to nutritionally enhance their diet.  相似文献   
8.
INTRODUCTIONGal a(1, 3) Gal (gal epitope) is a carbohydrate epitope, which is produced in large amounton the cells of pigs, mice and New World monkey(monkey of South America) by the glycosylationenzyme G alal 1 ) 4G IcNAc3- a- D- galactosyltransferase[or(1, 3)GT; EC2.4.1.511111. This enzyme is active in the Golgi appaxatus of cells and transfers galactose from the sugandonor uridine diphoSphate galactose (UDP-galactose) to the acceptor Nacetyllactosamine residue (Galaal-4GlcNAc-R…  相似文献   
9.
A clonal selection based memetic algorithm is proposed for solving job shop scheduling problems in this paper. In the proposed algorithm, the clonal selection and the local search mechanism are designed to enhance exploration and exploitation. In the clonal selection mechanism, clonal selection, hypermutation and receptor edit theories are presented to construct an evolutionary searching mechanism which is used for exploration. In the local search mechanism, a simulated annealing local search algorithm based on Nowicki and Smutnicki's neighborhood is presented to exploit local optima. The proposed algorithm is examined using some well-known benchmark problems. Numerical results validate the effectiveness of the proposed algorithm.  相似文献   
10.

Background

Pseudoxanthoma elasticum (PXE), caused by mutations in the ABCC6 gene, is a rare multiorgan disease characterized by the mineralization and fragmentation of elastic fibers in connective tissue. Cardiac complications reportedly associated with PXE are mainly based on case reports.

Methods

A cohort of 67 PXE patients was prospectively assessed. Patients underwent physical examination, electrocardiogram, transthoracic echocardiography, cardiac magnetic resonance imaging (CMR), treadmill testing, and perfusion myocardial scintigraphy (SPECT). Additionally, the hearts of a PXE mouse models (Abcc6−/−) and wild-type controls (WT) were analyzed.

Results

Three patients had a history of proven coronary artery disease. In total, 40 patients underwent exercise treadmill tests, and 28 SPECT. The treadmill tests were all negative. SPECT showed mild perfusion abnormalities in two patients. Mean left ventricular (LV) dimension and function values were within the normal range. LV hypertrophy was found in 7 (10.4%) patients, though the hypertrophy etiology was unknown for 3 of those patients. Echocardiography revealed frequent but insignificant mitral and tricuspid valvulopathies. Mitral valve prolapse was present in 3 patients (4.5%). Two patients exhibited significant aortic stenosis (3.0%). While none of the functional and histological parameters diverged significantly between the Abcc6−/− and WT mice groups at age of 6 and 12 months, the 24-month-old Abcc6−/− mice developed cardiac hypertrophy without contractile dysfunction.

Conclusions

Despite sporadic cases, PXE does not appear to be associated with frequent cardiac complications. However, the development of cardiac hypertrophy in the 24-month-old Abcc6−/− mice suggests that old PXE patients might be prone to developing late cardiopathy.  相似文献   
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