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91.
Sheep erythrocytes (E) which, with or without certain treatments, are currently used as “immunological reagents” to detect
cells with specific receptors (by rosette-formation) have been partitioned in two-polymer aqueousphase systems selected so
as to reflect charge-associatedor lipid-related membrane surface properties. We have found that the partitioning behavior of E is not affected in these phases
by reacting the cells with anti-E antibody (either IgG or IgM), forming EA. The additional binding of complement to the cell-antibody
complex, forming EAC, results, however, in a marked decrease in the partition coefficient,K. Apparently both the charge-associated and hydrophobic properties reflected by partitioning remain accessible to the phase
polymers when the cells are coated with antibody, but are not with the addition of complement. It is interesting that EA can
still rosette with T-lymphocytes (14), a property of E, while the additional coating with complement results in EAC which does not appreciably do so (26).
Neuraminidase or trypsin treatments of E, which yield Es having quite different rosetting properties with T-lymphocytes (14), cause increasedKs and unchangedKs, respectively, in phases reflecting lipid-related surface properties. Either treatment causes reducedKs of E in charged-phase systems. Neuraminidase treatment also results in a reduced electrophoretic mobility of E, while trypsin
treatment is not detectable by cell electrophoresis (25). We are currently studying the possible usefulness of employing cell electrophoresis and cell partitioning in charged-phase
systems jointly to obtain information on events occurring at the shear plane versus those occurring deeper in the membrane. 相似文献
92.
Summary Freeze-etching images of the capillary endothelium in the thyroid of normal, TSH-treated and Thyradin (powdered thyroid)-treated mice were examined. Numerous pores represent vesicular stomata or fenestrations. The number of the pores and their population density are increased in TSH-treated mice, and decreased in Thyradin-treated animals. In addition, the width of the parajunctional zone and of the flat ray free from endothelial pores is smaller in TSH-treated mice and larger in Thyradin-treated animals. These facts indicate that the number of endothelial pores changes according to the functional activity of the gland.Supported by a grant from the Japanese Educational Ministry 相似文献
93.
Summary Mineralized plaques, which develop at the site of repeated subcutaneous injections of 100 g KMnO4/0.2 H2O in rats, were investigated by electron microscopy. The newly formed, delineated, white plaque tissue at the injection site consisted of numerous, mostly unaltered fibroblasts and collagen fibers, without participation of inflammatory cells. Some signs of cell injury were found in the center of the lesions. Numerous, irregularly distributed, small, mineralized foci were seen near the fibroblasts. These were formed by aggregation of small needle-like units (50 Å in diameter and 0.05–2.0 m long). These needle-shaped units were found either in vesicular, cell derived structures, considered to be shed cell processes or cell fragments, or on collagen fibers. Intramitochondrial deposits of such needle-like units were seen frequently. Fusion of smaller mineralized foci to larger plaques occured and then needle-shaped units were seen at the periphery of the electron-dense lesions. Hypotheses concerning the mechanism of experimental cutaneous calcinosis (soft tissue mineralization) are discussed and related to the findings of this study. Probable intracellular crystal deposition and mineralization in cell-derived structures were shown for the first time in topical cutaneous calcinosis. 相似文献
94.
Abstract The Dutch have a long tradition of hospitality towards ethnic immigrants. In the nineties, however, quite dramatic changes have taken place among the Dutch. The central question addressed in this contribution is: to what extent do specific categories within the electorate favour ethnocentric policies? This question is answered by deducing hypotheses that are tested using recent data polled within the framework of the Dutch National Election Studies. Our crucial conclusion is that a rather widespread support for ethnocentric policies is present in contemporary Dutch society, especially among manual labourers, self‐employed and lowly educated people, but also among young cohorts and among modal income categories. 相似文献
95.
A. Duque P. Manzanares I. Ballesteros M.J. Negro J.M. Oliva F. Saez M. Ballesteros 《Process Biochemistry》2013,48(5-6):775-781
In this work, an integrated one-step alkaline–extrusion process was tested as pretreatment for sugar production from barley straw (BS) biomass. The influence of extrusion temperature (T) and the ratio NaOH/BS dry matter (w/w) (R) into the extruder on pretreatment effectiveness was investigated in a twin-screw extruder at bench scale. A 23 factorial design of experiments was used to analyze the effect of process conditions [T: 50–100 °C; R: 2.5–7.5% (w/w)] on composition and enzymatic digestibility of pretreated substrate (extrudate). The optimum conditions for a maximum glucan to glucose conversion were determined to be R = 6% and T = 68 °C. At these conditions, glucan yield reached close to 90% of theoretical, while xylan conversion was 71% of theoretical. These values are 5 and 9 times higher than that of the untreated material, which supports the great potential of this one-step combined pre-treatment technology for sugar production from lignocellulosic substrates. The absence of sugar degradation products is a relevant advantage over other traditional methods for a biomass to ethanol production process since inhibitory effect of such product on sugar fermentation would be prevented. 相似文献
96.
97.
《Anthrozo?s》2013,26(2):123-126
ABSTRACTThe normal development of empathy has been proposed to be imperative to the healthy emotional and social functioning of youths. In contrast, compromised levels of empathy have been linked to an increased propensity to engage in antisocial behaviors, including animal cruelty. Previous findings have revealed parent attachment to be intrinsically linked to the development of empathy. This association has been shown to play a role in predicting the expression of various outcome behaviors, including both those which are prosocial in nature, and those which are antisocial, and potentially aggressive. This study examines these associations in a sample of 281 12- to 18-year-old students. The aims included the investigation of the direct predictive roles played by attachment and empathy for prosocial and antisocial behaviors directed at both humans and animals. We also investigated the mediating role played by empathy in these relationships. Attachment and empathy significantly predicted prosocial and antisocial behaviors, both individually, and in combination. Furthermore, empathy was found to serve a mediating role in the associations between attachment and: human-directed prosocial behavior, the humane treatment of animals, and animal cruelty. These findings expand upon existing literature by demonstrating that it is, at least partially, through empathy that attachment to parents predicts prosocial and antisocial behaviors during adolescence. This is in contrast to the direction of relationships implied by some previous findings and proposals, which have suggested that treating animals humanely fosters the normal development of empathy, for example. Notwithstanding the promising findings revealed by the current study, we recommend that replicating this research using a larger sample will assist in addressing the limited generalizability identified in the current study. It is further proposed that the use of a lie scale could limit the influence of social desirability responding. Future research is also needed to determine the direction of the demonstrated relationships. 相似文献
98.
Cancer is the second leading cause of death worldwide. Research on the relationships between trace elements (TE) and the development of cancer or its prevention is a field that is gaining increasing relevance. This review provides an evaluation of the effects of TE (As, Al, B, Cd, Cr, Cu, F, I, Pb, Li, Mn, Hg, Mo, Ni, Se, Si, Sn, V and Zn) intake and supplementation in cancer risk and prevention, as well as their interactions with oncology treatments. Advancements in the knowledge of TE, their dietary interactions and their main food sources can provide patients with choices that will help them to improve their quality of life and therapy outcomes. This approach could open new opportunities for treatments based on the integration of conventional therapies (chemotherapy, radiotherapy, and immunotherapy) and dietary interventions that provide advanced personalized treatments. 相似文献
99.
Dafei Chai Dong Qiu Zichun Zhang Shang Yuchen Shi Gang Wang Lin Fang Huizhong Li Hailong Li Hui Tian Junnian Zheng 《Journal of cellular and molecular medicine》2020,24(18):10744-10755
Conditionally replicative adenoviruses (CRAds) were promising approach for solid tumour treatment, but its oncolytic efficiency and toxicity are still not satisfactory for further clinical application. Here, we developed the CAIX promotor (CAIXpromotor)‐controlled CRAd armed with a tumour suppressor absent in melanoma 2 (AIM2) to enhance its oncolytic potency. The CAIXpromotor‐AIM2 adenoviruses (Ad‐CAIXpromotor‐AIM2) could efficiently express E1A and AIM2 in renal cancer cells. Compared with Ad‐CAIXpromotor, Ad‐CAIXpromotor‐AIM2 significantly inhibited cell proliferation and enhanced cell apoptosis and cell killing, thus resulting in the oncolytic efficiency in 786‐O cells or OSRC‐2 cells. To explore the therapeutic effect, various Ads were intratumourally injected into OSRC‐2‐xenograft mice. The tumour growth was remarkably inhibited in Ad‐CAIXpromotor‐AIM2‐treated group as demonstrated by reduced tumour volume and weight with a low toxicity. The inflammasome inhibitor YVAD‐CMK resulted in the reduction of anti‐tumour activity by Ad‐CAIXpromotor‐AIM2 in vitro or in vivo, suggesting that inflammasome activation response was required for the enhanced therapeutic efficiency. Furthermore, lung metastasis of renal cancer mice was also suppressed by Ad‐CAIXpromotor‐AIM2 treatment accompanied by the decreased tumour fossil in lung tissues. These results indicated that the tumour‐specific Ad‐CAIXpromotor‐AIM2 could be applied for human renal cancer therapy. The therapeutic strategy of AIM2‐based CRAds could be a potential and promising approach for the therapy of primary solid or metastasis tumours. 相似文献
100.
There have been several reports that individuals with Fragile X syndrome (FXS) and animal models of FXS have communication deficits. The present study utilized two different call classification taxonomies to examine the sex‐specificity of ultrasonic vocalization (USV) production on postnatal day (PD8) in the FVB strain of Fmr1 knockout (KO) mice. One classification protocol requires the investigator to score each call by hand, while the other protocol uses an automated algorithm. Results using the hand‐scoring protocol indicated that male Fmr1 KO mice exhibited longer calls (P = .03) than wild types on PD8. Male KOs also produced fewer complex, composite, downward, short and two‐syllable call‐types, as well as more frequency steps and chevron call‐types. Female heterozygotes exhibited no significant changes in acoustic or temporal aspects of calls, yet showed significant changes in call‐type production proportions across two different classification taxonomies (P < .001). They exhibited increased production of harmonic and frequency steps calls, as well as fewer chevron, downward and short calls. According to the second high‐throughput analysis, female heterozygotes produced significantly fewer single‐type and more multiple‐type syllables, unlike male KOs that showed no changes in these aspects of syllable production. Finally, we correlated both scoring methods and found a high level of correlation between the two methods. These results contribute further knowledge of sex differences in USV calling behavior for Fmr1 heterozygote and KO mice and provide a foundation for the use of high‐throughput analysis of neonatal USVs. 相似文献