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1.
Young Norway spruce stands (Picea abies [L.] Karst) are typically cleaned of non-crop species on one or several occasions during young stand stage. In order to objectively evaluate the perceived benefits of early cleaning (EC), we studied the effects of EC on three study sites 2–2.5 years after receiving the treatment. Experiments were established as a randomised complete block design with a total of 40 blocks. Although height growth and mortality were not significantly affected, we found that EC substantially reduced canopy competition and, consequently, the mean diameter of released spruce grew 21–32% faster depending on the site. Furthermore, non-crop trees that were cleared during EC had fewer sprouts in two of the three sites and the sprouts were substantially smaller than the corresponding non-crop trees on control in all sites. EC can reduce the cost of pre-commercial thinning because EC reduced the estimated time needed for subsequent management by 18–49%. Thus, EC offers forest owners and managers an economically viable young stand management option. 相似文献
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Mark D. Dunbar Pamela Ginn Matthew Winter Karri Barabas Miller William Craft 《Veterinary clinical pathology / American Society for Veterinary Clinical Pathology》2012,41(4):590-593
A 3‐year‐old, female spayed Australian Shepherd dog was presented to Veterinary Healthcare Associates in Winter Haven, FL with a history of respiratory stridor, difficulty swallowing, and a change in bark for approximately 3 months. Radiographs revealed a soft tissue mass caudal to the epiglottis. Oral and computerized tomographic (CT) examinations were performed under general anesthesia and revealed a small firm mass in the caudal larynx on the right side. Cytologic evaluation of a fine‐needle aspirate of the mass revealed cells consistent with a rhabdomyoma, oncocytoma, or granular cell tumor. Histopathologic interpretation was rhabdomyoma or oncocytoma. Histochemical staining with periodic acid‐Schiff was mostly negative with a low number of weakly positive cells and with phosphotungstic acid‐hematoxylin was strongly positive with visible cross striations. Tumor cells did not express pancytokeratin AE1/AE3, were strongly immunoreactive for myoglobin and muscle‐specific actin, and did not express vimentin except for a low number of weakly immunoreactive cells. These findings confirmed a diagnosis of rhabdomyoma. Primary neoplasia of the larynx is rare, and widely varying types of neoplasms have been documented in this location. Due to the cytologic and histologic similarities between rhabdomyoma, oncocytoma, and granular cell tumor, these neoplasms should be differentiated using histochemical staining and immunohistochemical analysis. 相似文献
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Henry CJ Downing S Rosenthal RC Klein MK Meleo K Villamil JA Fineman LS McCaw DL Higginbotham ML McMichael J 《American journal of veterinary research》2007,68(11):1246-1251
OBJECTIVE: To evaluate safety and efficacy of LDI-100, a preparation containing human chorionic gonadotropin (hCG) and bacillus Calmette-Guerin (BCG), in the treatment of dogs with mast cell tumors and to compare results with those from a control group receiving single-agent vinblastine. ANIMALS: 95 dogs with measurable grade II or III mast cell tumors. PROCEDURES: Dogs were randomized to receive either LDI-100 (1.35 ng of BCG and 2 units of hCG, SC, q 24 h) or vinblastine (2 mg/m(2), IV, q 1 wk) for 6 weeks. Tumors were measured at baseline and day 42, and dogs were monitored for signs of toxicosis. Clinical performance scores were recorded at each visit. Differences in host factors (sex, weight, and age), clinical performance score, tumor response, and adverse events were analyzed. RESULTS: 46 dogs received LDI-100, and 49 dogs received vinblastine. No significant differences were found between the 2 treatment groups with regard to host factors or clinical performance score. Tumor response (>or=50% reduction) rates were similar between the LDI-100 and vinblastine group (28.6% and 11.7%, respectively). Dogs in the LDI-100 group had significantly less neutropenia than the vinblastine group. CONCLUSIONS AND CLINICAL RELEVANCE: hCG and BCG have immunomodulatory and antitumor effects against a variety of malignancies in humans and dogs. In this study, LDI-100 provided clinical responses comparable to single-agent vinblastine chemotherapy but without myelosuppression. LDI-100 is a promising new agent that should be further investigated for multimodality therapy of mast cell tumors in dogs. 相似文献
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Sanna K. Saarikoski Markus K. Sillanpää Karri M. Saarnio Risto E. Hillamo Arto S. Pennanen Raimo O. Salonen 《Water, air, and soil pollution》2008,189(1-4):265-277
The distribution of nonylphenol ethoxylates (NPEOn) and their derivatives of nonylphenol (NP) and nonylphenoxy ethoxy acetic acids (NPEnC) in the sediments of a relatively closed freshwater reservoir was investigated using sediment layers sliced from undisturbed sediment cores collected with a gravity core sampler at three sampling sites (St. 1, St. 2 and St. 3) along the water flow direction. The relationships between the bound content of these compounds and the sediment organic matter as well as the likely transformation pathways were evaluated. The total content of NPEOn (n?=?1–15) fell in 84.6–336.5, 59.9–135.5 and 77.0–623.4 μg/kg-dry for all sliced layers at St.1, St.2 and St.3, respectively, with the content of individual NPEOn species showing a general decreasing trend with the attached molar number of the ethoxy (EO) chain. Compared to each detected NPEOn species, the bound content of NP was much higher, falling in 73.2–248.4, 79.9–358.2 and 25.5–1,988.4 μg/kg-dry at St. 1, St. 2 and St. 3, respectively. A general increasing trend of the NP content along the water flow direction of the reservoir was revealed. NPEnC (n?=?1–10) varied in 1.93–4.12, 2.85–9.84 and 1.05–19.1 μg/kg-dry for sediment at the respective site of St. 1, St. 2 and St. 3, with the averaged values at these sites (2.91, 4.71 and 6.72 μg/kg-dry) showing an increasing trend from the upstream to the downstream. For NPEnC, a parametric trend of increases in the content of NPE1C, NPE2C and NPE3C with the bound sediment organic matter (9.06–11.8%) seemed to be existent. Furthermore, the computed magnitudes of NPEO1–2/NPEO1–15, NP/NPEO1–15 and NPEC1–10/NPEO1–15 suggested that non-oxidative hydrolytic transformation was probably prevailing within the sedimented mud phase of the reservoir, with the oxidative hydrolytic transformation pathway being less involved. 相似文献
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Lamsa KP Heeroma JH Somogyi P Rusakov DA Kullmann DM 《Science (New York, N.Y.)》2007,315(5816):1262-1266
Long-term potentiation (LTP), which approximates Hebb's postulate of associative learning, typically requires depolarization-dependent glutamate receptors of the NMDA (N-methyl-D-aspartate) subtype. However, in some neurons, LTP depends instead on calcium-permeable AMPA-type receptors. This is paradoxical because intracellular polyamines block such receptors during depolarization. We report that LTP at synapses on hippocampal interneurons mediating feedback inhibition is "anti-Hebbian":Itis induced by presynaptic activity but prevented by postsynaptic depolarization. Anti-Hebbian LTP may occur in interneurons that are silent during periods of intense pyramidal cell firing, such as sharp waves, and lead to their altered activation during theta activity. 相似文献
7.
Tuber shape is a genetically determined, important varietal characteristic that is also influenced by environmental factors.
In this study, the overall dimensions of tubers of two potato cultivars (Van Gogh and Yukon Gold) were determined using a
triaxial ellipsoid model that was found to encompass the main varietal differences. The more detailed surface features were
captured using a spherical-harmonics series representation for the residual undulation. The method was then applied to four
additional cultivars (Bellona, Lady Rosetta, Pito, and Sabina). Modelling the undulation of tuber surface in addition to the
overall dimensions indicated that cultivars differed in the global shape and, in specific cases, also in the surface undulation
of tubers. The new, improved method for modelling tuber shapes can thus capture and distinguish the overall three-dimensional
shape and irregularities caused by growth conditions and other factors. It is envisaged to be useful for quantitative genetics
approaches aiming to resolve the relative impact of different genes on tuber shape, as well as for various machine vision
and other applications. 相似文献
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A Prospective Study of Radiation Therapy for the Treatment of Grade 2 Mast Cell Tumors in 32 Dogs 总被引:2,自引:0,他引:2
Renee Al-Sarraf DVM G. Neal Mauldin Amiya K. Patnaik Karri A. Meleo 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》1996,10(6):376-378
Surgery, chemotherapy, and irradiation have been used singly or in combination to treat dogs with cutaneous grade-2 mast cell tumors (MCT). However, optimal treatment has not been established. At The Animal Medical Center, 32 dogs with grade 2, stage 0 MCT received cobalt radiation treatment to a dose of 54 Gy; 94% had a disease-free interval of 1 year. The 2–,3–,4–, and 5–year disease-free intervals were 86%. Survival rates were 100% for 1 year and 96% for 2 to 5 years, with only 1 death caused by MCT. Primary site was not a prognostic factor for survival in this study. Minimal toxicity was observed and was limited to acute cutaneous reactions. Late-term reactions to radiation therapy were mild and considered acceptable in all cases. No deaths occurred due to treatment, and no dog was eliminated from the study because of radiation therapy toxicity. Radiation therapy appears to be an effective treatment for dogs with grade 2, stage 0 MCT. 相似文献
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Veikko Hiltunen Mikko Kurttila Pekka Leskinen Karri Pasanen Jouni Pykäläinen 《Forest Policy and Economics》2009,11(1):1-9
We tested the Mesta Internet-based decision-support application in connection with a natural resources planning (NRP) process in Eastern and Western Lapland, Finland. The aim in this process was to define the land-use allocation and the corresponding forest management operations for state-owned forests within these planning regions. Mesta was used in examining and evaluating the strategy alternatives from the viewpoint of the stakeholders' objectives. The basic idea in using Mesta is to define the acceptance thresholds that divide the alternatives into ‘acceptable’ and ‘not acceptable’ alternatives with respect to each decision criterion. The thresholds are adjusted holistically, i.e. so that all decision criteria and criteria values of all decision alternatives are simultaneously visible from the user interface. The holistic adjustment process is continued until an acceptable solution compliant with the production possibilities of the planning area is found. In the NRP process, the members of the stakeholder group first used Mesta individually to set their own thresholds. Next, the participants' acceptance thresholds were combined and a negotiation process was launched to find the group's common acceptance thresholds. This negotiation was also supported by Mesta. The result of the negotiation was that the participants were able to collaboratively decide on their recommendation for the future land-use allocation and the forest management principles to be applied in the two planning regions. The main benefit of Mesta as a decision-support tool during the negotiation process of the group was that the participants were forced to merge their preferences with the realistic production possibilities of the planning regions. 相似文献