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The aim of this study was to perform a pilot histological and quantitative analysis of the blood vessels accompanying the epicardial nerves (vasa nervorum) in the porcine hearts. Twenty healthy porcine hearts were used in this study. The blood vessels were analyzed by light microscopy using four different staining techniques in transverse sections taken from the upper, middle, and lower segments of the anterior part of the interventricular region and the adjacent parts of the right and left ventricles containing epicardial nerves and the endocardial peripheral parts of the Purkinje fibers. In total, 317 epicardial nerves were detected. The vasa nervorum were present in 75.7% of these nerves. The vasa nervorum resembled arterioles and postcapillary and collecting venules. One hundred and forty nine epicardial nerves were perivascular, located in the adventitia of the anterior interventricular artery and vein. The remaining 168 nerves ran freely through the epicardial interstitium. The presence of the vasa nervorum was not related to topographical location or nerve diameter. Additionally, from a total of 33 analyzed ventricular complexes of Purkinje fibers small blood vessels located in their proximity were identified in only two cases. It can be concluded that the majority of the anterior epicardial nerves of porcine heart possess well-developed vasa nervorum. In contrast, similar blood vessels are rarely present in the vicinity of the Purkinje fibers. The data obtained contribute to a better understanding of the nutrition of the cardiac nerves.  相似文献   
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Isoflavones (ISOs) are bioactive food ingredients of the traditional East Asian diet and currently discussed as alternatives to classical hormone replacement therapies and for reducing the prevalence of hormone-dependent cancers. Although there are many studies on ISOs, not much is known about their long-term effects.Therefore, we performed an animal experiment analyzing the effects of three different diets: a phytoestrogen-free diet, a diet supplemented with genistein (700 μg/g diet) and an ISO-high diet (232 μg daidzein and 240 μg genistein/g) at two distinct time points, juvenile (21 days) and adult (97 days). Exposure started prior to mating of the parents and throughout the life of the offspring.We observed a stronger increase of uterine wet weights in juvenile offspring with genistein exposure (1018 ± 350 mg/kg BW) than with ISO-high diet (497 ± 133 mg/kg BW). Whereas the expression of proliferation related genes (PCNA; Ki67; IGF-1; IGF-1R), analyzed by real-time-qPCR and Western blot, were significantly down-regulated in juvenile animals exposed to genistein. Additionally, genistein exposure led to estrogenic responses, observed upon increase of complement C3 and decrease of estrogen receptors gene expressions, while the exposure to ISO-high diet did not show these effects.In conclusion, both the time point on which phytoestrogen exposure starts together with the composition of the ingested phytoestrogen containing diet are of great importance for the biological response of the offspring.  相似文献   
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Ohne Zusammenfassung  相似文献   
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Survival was estimated for shortfin mako Isurus oxyrinchus in the north-west Atlantic from tag-recapture data. The data used in this study were collected by the National Marine Fisheries Service Cooperative Shark Tagging Programme from 1962 to 2003. In total, 6309 shortfin mako sharks were tagged, of which 730 were recaptured. The high recapture rate of 11·6% for this species provided adequate recapture data to carry out survival analyses. Estimates of survival were generated with the computer software MARK, which provided a means for estimating parameters from tagged animals when they were recaptured. The results of several models are presented with various combinations of constant and time-specific survival and recovery rates. A parametric bootstrap and the median variance inflation factor ( ) approach were used to test the fit of the general model to the data. The estimated indicated a very good model fit. The models with time invariant survival rate had the most support from the data and no group or time period effects were found. Recovery rate ( f ) appeared to increase from 0·043 in the early years to 0·056 in the later years. The nominal survival rate of 0·59 year−1 was adjusted with an estimated tag-shedding rate of 0·26 year−1 to generate a final corrected annual survival estimate of 0·79 with a 95% CI of 0·71–0·87.  相似文献   
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Herein we have analyzed the expression of idiotopes associated with a monoclonal anti-tumor-associated antigen (TAA) antibody in DBA/2 mice which have progressively growing tumors or resist tumor growth. A panel of eight monoclonal antiidiotypic antibodies raised against a monoclonal antibody which reacts with a mouse mammary tumor virus cross-reactive qp52 envelope protein (TAA) of the L1210/GZL lymphoma was used to measure the expression of idiotopes in sera from different treatment groups. Significant correlations between the expression of certain idiotopes and the growth of the tumor or the establishment of anti-tumor immunity are seen. 1) Idiotypes detected by anti-idiotype D11 are high in anti-idiotype immunized progressor or tumor-susceptible mice and low or absent in regressor mice, i.e., the mice immunized with the protective 2F10 anti-idiotype; 2) the 3A4-detected idiotypes are less frequent or absent in irradiated tumor-immunized regressor mice than in untreated mice challenged with live tumor or progressor mice; 3) no difference in the anti-TAA titers is seen in mice in which the tumor growth is inhibited and in mice in which the tumor grows; 4) no difference in 11C1 idiotype + anti-TAA titer was observed between regressor and progressor mice; and 5) mice with normal or accelerated tumor growth have higher titers of idiotypes detected by a polyclonal anti-idiotype. These findings provide evidence for a regulatory idiotype network induced by the growing L1210/GZL tumor or by anti-idiotypic immunization. The titer of anti-TAA antibody does not correlate with the biology of tumor growth, but certain idiotopes correlate with either progressive or regressive tumor behavior. Therefore, the target of the idiotype regulation is likely to be anti-tumor T effector cells. Effective idiotype therapy of tumors must deal with the complexity of idiotype regulation induced by the tumor itself and is unlikely to be successful if anti-idiotypes are used only as internal mimicry of a TAA.  相似文献   
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In the present study we report on the effects of commonly used nonsteroidal antiinflammatory drugs on metallothionein (MT) and MT-I mRNA levels. A single dose of chloroquine (100 mg/kg), diclofenac (100 mg/kg), indomethacin (10 mg/kg), or piroxicam (100 mg/kg) was administered ip to C57B1 mice. After 18 h, MT levels were determined with a Cd-saturation radioassay. MT-I mRNA levels were measured by Northern Blot analyses using a probe containing the mouse MT-I gene. All drugs tested caused an increase in the MT content of the liver but not of the kidneys and lung. The lowest and highest effects were observed with chloroquine (8 times the control value) and diclofenac (18 times), respectively. In accordance with the stimulation of MT synthesis, increased accumulation of hepatic MT-I mRNA could be demonstrated. These results indicate that elevated MT levels may contribute to the effectiveness of nonsteroidal antiinflammatory drugs in the treatment of rheumatoid arthritis (RA).  相似文献   
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