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1.
Soils from four estuaries of SW Iberian Peninsula, affected by anthropogenic influence (urban, industrial and agricultural activities), were analyzed for the occurrence of a variety of metals and trace elements including Al, As, B, Ba, Ca, Cd, Co, Cr, Cu, Fe, K, Mg, Mn, Na, Ni, P, Pb, S and Zn. The soils presented very high levels of salinity (high concentrations of Na, K and Mg), organic matter and, consequently, of C and N concentrations. In contrast, very low values of CaCO3, Ca and P were found. In addition, it should be highlighted that in certain localities (Piedras 1 and 2 and Guadiana in Huelva, Spain, and Ria Formosa, Faro, Portugal) the concentrations of Pb, S and Zn were extremely high, reaching levels of pollution.  相似文献   
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The presence and distribution of peptidergic nerve fibers were studied in the testis and mesorchium of the toad by means of immunohistochemistry. Cryostat sections of the testis and whole-mount preparations of mesorchia were immunostained with antisera to calcitonin gene-related peptide (CGRP) and neuropeptide tyrosine (NPY). After leaving the mesorchium CGRP-immunoreactive (IR) fibers were seen predominantly running in between the seminiferous tubules. In addition, a small population of CGRP-IR nerve fibers formed thin plexuses around blood vessels. Conversely, NPY-like immunoreactivity predominated in nerve fibers that formed dense plexuses around vessels both in the mesorchium and testis. Additionally, some single NPY-IR nerve fibers could be seen in both structures studied. The functional significance of these peptidergic systems in the testis of the toad remains to be analyzed.  相似文献   
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Background  

Thermotolerant Campylobacter is among the more prevalent bacterial pathogens that cause foodborne diseases. This study aimed at evaluating the occurrence of thermotolerant Campylobacter contamination in chicken carcasses and processing plant stations (chilling water, scalding water, defeathering machinery, evisceration machine, and transport crates) in two of the Chilean main slaughterhouses. In addition, the isolation rates of thermotolerant Campylobacter during evisceration and following chiller processing were compared.  相似文献   
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Cortical tubular cultures enriched with distal segments were prepared from the kidney of adult Fisher 344 rats bearing thyroid tumors. After two years of cultivation (20 passages) cell monolayers contained immunocytochemically detectable cytokeratin and kallikrein material in their cytoplasm. Furthermore cell pellets showed a true renal type of kininogenase activity corresponding to active kallikrein which ranged from 22.3 to 1.5, and total Kallikrein from 29.9 to 2.8 pg kinins/min per mg of protein.  相似文献   
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A new genus and species of the subfamily Callodistomidae is described. The new genus is named Pirupalkia queulensis n. gen., and was found in the small intestine of the fish Cilus montti. This new genus, compared with other genus of the subfamily differs principally in the distribution of the vitellaria and location of the uterus.  相似文献   
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