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11.
Intracerebroventricularly (icv) administered corticotropin-releasing hormone (CRH) produces a dose-dependent increase in heart rate in association with behavioral activation. The present study was designed to investigate whether these CRH-induced responses are dependent on adrenal function. The effects of adrenalectomy (ADX) and subsequent corticosterone replacement were studied. Administration icv of 300 ng of CRH failed to produce behavioral activation and tachycardia in ADX rats. Corticosterone replacement restored the CRH-induced behavioral response to preoperative levels, whereas the CRH-induced tachycardia was partially restored. This latter result may be related to the fact that the baseline heart rate of ADX animals appeared to be significantly higher than that of corticosterone-treated ADX animals. It is concluded that circulating adrenal corticosterone in ADX rats is involved in the expression of the behavioral and cardiac effect of central CRH.  相似文献   
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The phylogenetic relationships among the wall lizards of the Podarcis hispanicus complex that inhabit the south-east (SE) of the Iberian Peninsula and other lineages of the complex remain unclear. In this study, four mitochondrial and two nuclear markers were used to study genetic relationships within this complex. The phylogenetic analyses based on mtDNA gene trees constructed with ML and BI, and a species tree using *BEAST support three divergent clades in this region: the Valencia, Galera and Albacete/Murcia lineages. These three lineages were also corroborated in species delimitation analyses based on mtDNA using bPTP, mPTP, GMYC, ABGD and BAPS. Bayesian inference species delimitation method (BPP) based on both nuclear data and a combined data set (mtDNA + nuclear) showed high posterior probabilities for these three SE lineages (≥0.94) and another Bayesian analysis (STACEY) based on combined data set recovered the same three groups in this region. Divergence time dating of the species tree provided an estimated divergence of the Galera lineage from the other SE group (Podarcis vaucheri, (Albacete/Murcia, Valencia)) at 12.48 Ma. During this period, the Betic–Rifian arc was isolated, which could have caused the isolation of the Galera form distributed to the south of the Betic Corridor. Although lizards from the Albacete/Murcia and Galera lineage are morphologically similar, they clearly represent distinct genetic lineages. The noteworthy separation of the Galera lineage enables us to conclude that this lineage must be considered as a new full species.  相似文献   
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The topography of the auriculotemporal nerve (ATN) root system is the main criterion of this nerve classification. Previous publications indicate that ATN may have between one and five roots. Most common is a one- or two-root variant of the nerve structure. The problem of many publications is the inconsistency of nomenclature which concerns the terms “roots”, “connecting branches”, or “branches” that are used to identify the same structures. This study was performed on 80 specimens (40 adults and 40 fetuses) to propose a classification based on: (i) the number of roots, (ii) way of root division, and (iii) configuration of interradicular fibers that form the ATN trunk. This new classification is a remedy for inconsistency of nomenclature of ATN in the infratemporal fossa. This classification system has proven beneficial when organizing all ATN variants described in previous studies and could become a helpful tool for surgeons and dentists. Examination of ATN from the infratemporal fossa of fetuses (the youngest was at 18 weeks gestational age) showed that, at that stage, the nerve is fully developed.  相似文献   
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This clinical study is a first attempt to use autofluorescence for recurrence diagnosis of skin cancer in postoperative scars. The proposed diagnostic parameter is based on a reduction in scar autofluorescence, evaluated in the green spectral channel. The validity of the method has been tested on 110 postoperative scars from 56 patients suspected of non‐melanoma skin cancer, with eight patients (13 scars) available for the repeated examination. The recurrence diagnosis within a scar has been made after two subsequent autofluorescence check‐ups, representing the temporal difference between the scar autofluorescence amplitudes as a vector. The recognition of recurrence has been discussed to represent the significant deviations from the value of vector angle θ. This new autofluorescence‐based method can be easily integrated into the postoperative monitoring of surgical scars and can help diagnose the recurrence of skin cancer from the early stage of scar development.  相似文献   
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The effect of ethanol on the cardiovascular system (ECG, heart rate, blood pressure) was studied in anesthetized, nonstressed or stressed rats. In anesthetized rats, ethanol showed no effect on heart rate or ECG. In nonstressed rats, ethanol sedated the animals but increased heart rate significantly. This ethanol induced tachycardia seemed the result of a direct stimulation of the sympathetic nerves to the heart. Blood pressure was not significantly affected by ethanol in these nonstressed rats. In stressed rats, marked behavioral excitation and significant increases in heart rate and blood pressure were noted. Ethanol pretreatment calmed the animals considerably during restraint. Ethanol did reduce slightly the stress-induced tachycardia but markedly reduced or antagonized stress-induced blood pressure increases. No major changes in the ECG were noted during these studies with the exception of a few individual animals which showed pathologic ECG responses to ethanol. These data show that ethanol affects cardiovascular functions differently in anesthetized, nonstressed or stressed rats, and that ethanol can significantly reduce or antagonize stress-induced behavioral excitation, tachycardia and hypertension.  相似文献   
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The rabbit Acrosome Stabilizing Factor (ASF) is a glycoprotein synthesized in the corpus epididymis that reversibly decapacitates sperm. The effects of altering the conformation of ASF were evaluated by using a competitive enzyme-linked immunoabsorption assay (ELISA) with monoclonal antibodies that recognized either sequential or conformational determinants and/or an in vivo decapacitation assay. Heat denaturation (80 degrees C for 30 min) of affinity-purified ASF resulted in destruction of its native conformation concurrent with its loss of biological activity. Acid pH treatment of ASF also resulted in a conformational change in ASF, which caused a shift from the dimeric form (MW = 260,000) to the monomeric form (MW = 130,000). This manipulation allowed the biological activity of the monomeric form of ASF to be assayed separately from the dimer. The monomer was found to be biologically inactive. Proteolysis with trypsin or Staphylococcus-V8 treatment resulted in loss of the native conformation of the molecule, but Staphylococcus-V8 did not destroy the sequential determinant recognized in this analysis. This work indicates that conformation of the ASF macromolecule is important for its biological activity, and also provides a rapid means to evaluate potential decapacitation activity of purified ASF.  相似文献   
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Summary Skin tests with autologous cholesteryl hemisuccinate (CHS)-treated and untreated cells were performed in ten metastatic melanoma patients. In the majority of cases evident reaction was noted with CHS-treated cells (9/10) while the reaction with untreated cells was mostly negative (7/10). Tumour cell suspensions used for skin tests were characterized for reactivity with monoclonal antibody TAL 1B5 detecting the HLA-DR alpha chain. There were no differences between CHS-treated and untreated cells with respect to HLA-DR expression and no correlation was found between grade of skin reaction to CHS-treated cells and the proportion of HLA-DR positive cells in the injected cell sample.  相似文献   
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