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1.
We analysed genetic variation in the natural populations of a potential herbicide biocontrol agent, Chondrostereum purpureum, in Nordic and Baltic countries using random amplified microsatellite markers. The results showed high genetic diversity among the populations of this fungus, but almost a complete lack of local differentiation. The results implicate that any local strain from the area can be used as a biocontrol agent without a fear of introducing new genotypes to treatment areas.  相似文献   
2.
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   
3.
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   
4.
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   
5.
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   
6.
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.
8.
Acid hydrolysis, acid methanolysis, and enzymatic hydrolysis were compared for depolymerization of five different plant materials containing uronic acids. The analyzed plant materials were oat spelt, wheat straw, spruce thermomechanical pulp, aspen stemwood, and totally chlorine-free (TCF) bleached hardwood kraft pulp. Furthermore, GC (using both HP-1 and HP-5 capillary columns and FID and MSD detectors), HPAEC-PAD, and HPAEC-Borate techniques were compared for subsequent analysis of the released monosaccharides. It was shown that acid methanolysis combined with GC analysis is a convenient method for obtaining the sugar unit composition and amount of non-crystalline polysaccharides in different plant materials. The methanolysis method was generally superior to the hydrolysis method for xylan- and uronic acid-containing samples. However, acid and enzymatic hydrolysis showed the highest recoveries for bleached chemical pulp samples. Acid hydrolysis is also required for crystalline polysaccharides, but the strong acid conditions evidently lead to degradation of labile sugars. The plant methanolysates were not suitable as such for analysis on an HPAEC-PAD system. For analysis of the total amount of sugar units, hence including cellulose, other non-crystalline hemicelluloses, and pectins, a combination of the methanolysis and hydrolysis methods is recommended.  相似文献   
9.
Summary The ability of the European biotypes A and B of Gremmeniella abietina var. abietina to hybridize in artificial pairings was tested. Using three types of molecular markers progenies with parental markers mixed indicating that the two biotypes can hybridize were observed. However, the resulting progeny had a low rate of successful germination, grew poorly on artificial medium and one was most probably a partial diploid or heterokaryon. Thus, both biotypes are genetically distinct populations and should be described as separate species as soon as sufficient discriminating information is available.  相似文献   
10.
The effort of boreal forest conservation has emphasised the preservation of old-growth forests while the role of young successional stages in maintaining biodiversity has remained largely unstudied. We compared the richness of beetle species and composition of species assemblages between managed and seminatural forests in five stages of forest succession. The sites were in boreal sub-xeric pine-dominated forests in eastern Finland. Seminatural study sites, especially the recently burned sites, were important habitats for threatened and near-threatened species. We propose that young stages of natural succession should be included in the network of protected forest areas. On the other hand, the composition of saproxylic species assemblages in seminatural forests differed from the assemblages in managed forests, indicating also the need to improve the forest management guidelines so that they better address the requirements of species protection. Regeneration methods applied should resemble or mimic the natural disturbances more closely.  相似文献   
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