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31.
The full-length cDNA of dog preproendothelin-3 (PPET3) was cloned from lung tissue using RT-PCR and rapid amplification of cDNA ends. Aside from the poly (A) tail, the full-length cDNA was 1976 bp. A polyadenylation signal sequence and one copy of a consensus sequence, ATTTA, which is related to mRNA turnover, was found in the 3' noncoding region. The cDNA had a 594-bp open reading frame encoding a 198-amino acid polypeptide. Regions corresponding to a bioactive mature ET3 peptide, an intermediate form known as big-ET3, and an ET3-like peptide were observed in dog PPET3. Expression of PPET3 mRNA was detected throughout the organs examined, which included heart, lung, liver, kidney, spleen, stomach, pancreas, duodenum, colon, uterus, ovary and testis.  相似文献   
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Coronary artery spasm induced in atherosclerotic miniature swine   总被引:22,自引:0,他引:22  
Angiographically demonstrable coronary artery spasm could be provoked repeatedly by giving intracoronary or intravenous injections of histamine to miniature swine with experimentally induced atherosclerotic lesions of the coronary artery. The spasm induced in this way subsided either spontaneously or after the administration of nitroglycerin and was prevented by a calcium antagonist or an agent that blocks histamine H1 receptors. This model, which suggests that atherosclerotic changes may be one of the primary factors in the occurrence of coronary artery spasm, should facilitate studies on the pathogenesis of this condition.  相似文献   
34.
Membrane and secretory proteins cotranslationally enter and are folded in the endoplasmic reticulum (ER). Misfolded or unassembled proteins are discarded by a process known as ER-associated degradation (ERAD), which involves their retrotranslocation into the cytosol. ERAD substrates frequently contain disulfide bonds that must be cleaved before their retrotranslocation. Here, we found that an ER-resident protein ERdj5 had a reductase activity, cleaved the disulfide bonds of misfolded proteins, and accelerated ERAD through its physical and functional associations with EDEM (ER degradation-enhancing alpha-mannosidase-like protein) and an ER-resident chaperone BiP. Thus, ERdj5 is a member of a supramolecular ERAD complex that recognizes and unfolds misfolded proteins for their efficient retrotranslocation.  相似文献   
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We found that the oral administration of active egg white product (AEWP) enhances host resistance to infections. The prophylactic administration of AEWP enhanced nonspecific resistance in mice to systemic infection with E. coli. Moreover, the therapeutic administration of AEWP was effective against S. aureus infection in mice.  相似文献   
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Yeso sika deer captured in winter around Lake Akan in Hokkaido were reared for 8–10 months at Tokyo University of Agriculture in Abashiri. Six 1‐year‐old females and males and six 2‐year‐old or older (adult) females and males were slaughtered and their carcasses were processed. The chemical composition, mineral contents and fatty acid composition of the loin were measured. No marked influence of gender or age was noted in the chemical composition of loin. In the mineral contents, significant differences were noted. The potassium and sulfur contents were lower and the sodium content was higher in adult deer meat (P < 0.05, respectively) and the potassium content was higher in male deer meat (P < 0.05). Arsenic, cadmium or lead were not detected. In the unsaturated fatty acid, a significant interaction was detected (P < 0.05), and it was high in 1‐year‐old female deer meat and low in 1‐year‐old male deer meat. Significant gender or age differences were noted only in the mineral contents in the loin of deer reared for a short period after capture.  相似文献   
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We lack an understanding of nitrogen (N) cycles in tropical forests of Africa, although the environmental conditions in this region, such as soil type, vegetation, and climate, are distinct when compared with other tropical forests. Herein, we simultaneously quantified N fluxes through precipitation, throughfall, and 0-, 15-, and 30-cm soil solutions, as well as litterfall, in two forests with different soil acidity (Ultisols at the MV village (exchangeable Al3+ in 0–30 cm, 126 kmolc ha–1) and Oxisols at the AD village (exchangeable Al3+ in 0–30 cm, 59.8 kmolc ha–1)) over 2 years in Cameroon. The N fluxes to the O horizon via litterfall plus throughfall were similar for both sites (MV and AD, 243 and 273 kg N ha–1 yr–1, respectively). Those values were remarkably large relative to other tropical forests, reflecting the dominance of legumes in this region. The total dissolved N flux from the O horizon at the MV was 28 kg N ha–1 yr–1, while it was 127 kg N ha–1 yr–1 mainly as NO3-N (~80%) at the AD. The distinctly different pattern of N cycles could be caused by stronger soil acidity at the MV, which was considered to promote a superficial root mat formation in the O horizon despite the marked dry season (fine root biomass in the O horizon and its proportion to the 1-m-soil profile: 1.5 Mg ha–1 and 31% at the MV; 0.3 Mg ha–1 and 9% at the AD). Combined with the published data for N fluxes in tropical forests, we have shown that Oxisols, in combination with N-fixing species, have large N fluxes from the O horizon; meanwhile, Ultisols do not have large fluxes because of plant uptake through the root mat in the O horizon. Consequently, our results suggest that soil type can be a major factor influencing the pattern of N fluxes from the O horizon via the effects of soil acidity, thereby determining the contrasting plant–soil N cycles in the tropical forests of Africa.  相似文献   
40.
Abstract

Morphological and chemical properties of brown forest soils and podzolic soils developed on paleozoic shale under beech and/or cryptomeria have been studied with special reference to the eluviation-illuviation characteristics of Fe and Al.

Mobilization of Al was observed even in brown forest soils and its pattern was similar to that in podzolic soils. Its intensity was higher in the brown forest soils developed on the ridge under cryptomeria than in those on the slope under beech. Hence, podzolization is considered to be one of the genetic processes involved in the brown forest soils in question.

Furthermore, the value of (Fep+Alp)/clay that is employed to define a podzolic B or spodic horizon indicated the presence of a podzolic B horizon even in the brown forest soils studied, while no spodic horizon was found even in the podzolic soils with a clearly recognizable albic horizon. Moreover, the examination of the degree of podzolization showed that the brown forest soils almost corresponded to Ochreous brown earths.  相似文献   
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