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231.
CASE DESCRIPTION-A 6-year-old neutered male cat was examined because of a 4-week history of abnormal sounds while drinking and a previously noted mass at the base of the tongue. CLINICAL FINDINGS-Oral examination revealed a 1-cm-diameter midline cystic mass on the dorsal aspect of the base of the tongue at the junction of the rostral two-thirds and caudal third of the tongue. Complete blood count and serum biochemical analysis revealed no clinically relevant abnormalities, and serum total thyroxine and free thyroxine (determined by equilibrium dialysis) concentrations were within the reference range. TREATMENT AND OUTCOME-The fluid in the cystic mass was aspirated, and the remaining deflated mass was marsupialized. Histologic and immunohistochemical examination of sections of the excised mass revealed ectopic thyroid tissue. The cat recovered uneventfully from the surgery, clinical signs resolved, and the cat remained euthyroid with no recurrence of the mass as of 8 months after surgery. CLINICAL RELEVANCE-This is the first known reported case of ectopic lingual thyroid tissue in a male cat. In humans, the most common site of ectopic thyroid tissue is at the base of the tongue and the condition is disproportionately found in females, compared with males. In humans with ectopic lingual thyroid tissue, the patient often lacks any other functional thyroid tissue. However, the cat of this report remained euthyroid after mass resection.  相似文献   
232.
In the Congo Basin where most timber species are light-demanding, the low logging intensities commonly implemented (1-2 trees harvested ha−1) do not provide sufficient canopy gaps to ensure species regeneration. The regeneration of light-demanding timber species may therefore benefit from more intensive logging, or from post-harvest treatments such as thinning by poison girdling that increases light penetration. Little is known of the impact of post-harvest treatments on the floristic composition of tropical moist forests. This study therefore aimed to assess the effects of low and high selective logging (?2.33 and 4.73 trees harvested ha−1, and ?4.96 and 9.16 m2 ha−1 of basal area removed (logging + damage), respectively) - followed or not by thinning (?21.14 trees thinned ha−1, and ?6.57 m2 ha−1 of basal area removed) - on the floristic composition of a tropical moist forest in the Central African Republic, from 7 to 23 years after logging.We analyzed abundance data for 110 tree genera recorded every year for 14 years in 25 one-hectare permanent subplots. We used multivariate analysis to detect floristic variations between treatments and we assessed changes in floristic composition throughout the period. We compared floristic composition recovery between thinned and unthinned subplots, using unlogged subplots as a reference characterizing the pre-logging floristic composition.Logging and thinning had little impact on the floristic composition of the subplots as quantified 7 to 23 years later, though they did increase the proportion of pioneer species. Surprisingly, additional thinning at both logging levels failed to further distance floristic composition from that of the unlogged subplots, though it did increase disturbance intensity. Floristic composition recovery appeared to be facilitated when thinning was associated with logging. Thinning seemed to favor the growth and survival of non-pioneer species, to the detriment of pioneer species. These non-pioneer species could either be non-pioneer light demanders or shade-bearers. One explanation for this is that thinning by tree-poison girdling increased light availability without causing major damage to the forest, and thus increased the growth and survival of advance regeneration. The resulting enhanced competition then reduced the survival of pioneer species.  相似文献   
233.
Soils and sediments around gold ore deposit and mining sites in the Iron Quadrangle present positive As anomalies (median concentrations > 100 mg kg-1) and wide ranges (< 20 to > 2000 mg kg-1) even in densely populated areas. These anomalies can be related to geological structures, to hydrothermal ore deposits and to their continuous exploitation over the past three centuries. The paper presents new data on both As geochemistry and soil and sediment geochemistry in general, and discusses consequences of the encountered anomalies, their reasons and potential effects and how they compare with current screening and threshold values. While surface soil As-values are reproducible at a given site, sediment anomalies show a strong seasonal variation that can be explained by tropical hydrological variances. Suggestions are presented on how to minimize the As-load in densely populated areas that might otherwise pose a potential health risk.  相似文献   
234.
Influence of temporary stockpiling on the initial development of restored topsoils Due to increasing construction and open‐cast mining activities on fertile agricultural land, excavation, stockpiling, and restoration of soils have become important issues in soil protection. In this study, we performed a restoration experiment to investigate how the conditions during stockpiling may influence initial soil development and plant growth on a restored site. Four topsoils, which originated from two depths (with uninhibited and inhibited aeration) of a nontrafficked and a trafficked topsoil deposit, were repacked in strips and sown with three meadow‐seed mixtures in strips perpendicular to the soil strips. During stockpiling as well as during the first 2 years after restoration, we assessed the physical and mechanical properties of the topsoils and (after restoration) also plant growth. None of the investigated properties of the topsoils was influenced by the depth in the deposit. In contrast, the coarse porosity and compression index were lower, whereas the bulk density and precompression stress were higher in the trafficked than in the nontrafficked topsoil deposit. However, these differences largely disappeared already in the course of soil restoration. Contrary to our expectations, the plants grew better on the soil of the trafficked topsoil deposit than on the soil of the nontrafficked topsoil deposit in the year of restoration. This might be attributed to the extremely dry and hot summer of that year. In the course of the 2 years following restoration, also the differences in plant growth tended to disappear. The remaining differences in bulk density and plant growth could not be attributed to differences in stockpiling conditions. The results suggest a re‐examination of current soil restoration guidelines. The maximum permitted stockpiling heights for topsoils might be increased in order to reduce the areas required for temporary stockpiling.  相似文献   
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236.
Members of the Toll-like receptor (TLR) and interleukin-1 receptor (IL-1R) superfamily share an intracytoplasmic Toll-IL-1 receptor (TIR) domain, which mediates recruitment of the interleukin-1 receptor-associated kinase (IRAK) complex via TIR-containing adapter molecules. We describe three unrelated children with inherited IRAK-4 deficiency. Their blood and fibroblast cells did not activate nuclear factor kappaB and mitogen-activated protein kinase (MAPK) and failed to induce downstream cytokines in response to any of the known ligands of TIR-bearing receptors. The otherwise healthy children developed infections caused by pyogenic bacteria. These findings suggest that, in humans, the TIR-IRAK signaling pathway is crucial for protective immunity against specific bacteria but is redundant against most other microorganisms.  相似文献   
237.
The aim of this experiment was to study the effect of feeding level (FL) on the digestibility of unconserved forage obtained from two permanent grasslands cut at three different dates during the first cycle of growth. Forage was offered to Texel sheep (wethers), at maintenance level and at ad libitum level. Differences in voluntary intake (VI) between grasslands were also tested. Organic matter digestibility (OMD) measured at ad libitum level and at VI was 13% higher on harvested forage from grassland rich in forbs (GRF) than grassland rich in grasses (GRG) at early herbage growth stages, but these differences were no longer found at later maturity stages. In GRF, there were no differences for OMD, at either FL at the young growth stages, but at the end of the cycle the OMD obtained at ad libitum level (0·56) was higher than that at maintenance level (0·50). However, in GRG, at an early stage of forage maturity, OMD at ad libitum level (0·67) was lower than that at maintenance level (0·70), but this difference was no longer found at the end of the growth cycle. In conclusion, the effect of FL on the digestibility of unconserved forage from permanent grasslands depends on the type of grassland. These differences are mainly explained by the different botanical composition of the grassland types.  相似文献   
238.
Sphingolipid metabolites regulate cellular processes such as cell proliferation, differentiation, and apoptosis. In this study, glucocerebrosides (GluCer) from rhizomes of Arisaema amurense and Pinellia ternata were fully characterized using 1- and 2-dimensional nuclear magnetic spin resonance (NMR) and circular dichroism (CD) spectroscopy and tandem collision-induced dissociation mass spectrometry (ESI-MS/CID-MS). Three new acylated and seven known GluCer were elucidated with 4,8-sphingadienine (4,8-SD, d18:2) as backbone. 4,8-SD is a metabolite after enzymatical hydrolysis of GluCer in the gut lumen. In this study, 4,8-SD was hydrolyzed from GluCer and chromatographically purified on silica gel. In contrast to the GluCer, 4,8-SD showed cytotoxic effects in the WST-1 assay. GluCer with 4,8-SD as sphingoid backbone are present in plants consumed as food, such as spinach, soy, and eggplant.  相似文献   
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