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91.
92.
Peroxisome proliferator-activated receptor alpha (PPARalpha) is mainly expressed in liver and involved in lipid metabolism. Oxidation of certain fatty acids in peroxisomes is under PPARalpha control. A wide variety of lipid molecules activate PPARalpha as well as the fibric acid derivative clofibrate. In the present study, we evaluated the differential activation of PPARalpha with several agonist ligands through its expression and DNA binding in both rat (McA-RH7777) and human (HepG2) hepatoma cell lines. In McA-RH7777 cells, clofibrate alone mediated a higher induction of PPARalpha expression than linoleic acid. In contrast, linoleic acid was the most effective ligand in HepG2 cells and treatment with clofibrate plus linoleic acid did not further increase PPARalpha expression. PPRE-binding activity of PPARalpha in ligand-treated cells was also increased in a parallel manner. We suggest that ligand-induced PPARalpha activation might give rise to differential species-dependent responses.  相似文献   
93.
The study of life history dynamics of the pine sawyer beetle Monochamus carolinensis (Olivier) is of interest because the beetles are vectors for the pinewood nematode, Bursaphelenchus xylophilus (Steiner and Buhrer) Nickle, the causal agent of pine wilt in susceptible pine trees. Previous observation of a laboratory colony of M. carolinensis suggested numbers of adult beetles reared from logs varied little in relation to oviposition densities among individual logs. Logs in laboratory colonies are routinely subjected to artificially high oviposition rates. The objectives of this study were to examine the relationship between initial oviposition rate, holding time (time between log cut and oviposition), log volume and area and adult survivorship in laboratory colony. This study examined the number of eggs, larvae, adults and generation survivorship in logs over a 2‐year period. The number of adults emerged per log was not related to the number of eggs laid. Late larval and adult numbers were significantly correlated with log size. Only 12% of the initial cohort completed development and emerged as adults. We attribute the high within‐log mortality of beetles to intraspecific competition and cannibalism.  相似文献   
94.
In an effort to characterize the role of the medullary lateral tegmental field (LTF) in regulating respiration, we tested the effects of selective blockade of excitatory (EAA) and inhibitory amino acid (IAA) receptors in this region on phrenic nerve activity (PNA) of vagus-intact and vagotomized cats anesthetized with dial-urethane. We found distinct patterns of changes in central respiratory rate, duration of inspiratory and expiratory phases of PNA (Ti and Te, respectively), and I-burst amplitude after selective blockade of EAA and IAA receptors in the LTF. First, blockade of N-methyl-D-aspartate (NMDA) receptors significantly (P < 0.05) decreased central respiratory rate primarily by increasing Ti but did not alter I-burst amplitude. Second, blockade of non-NMDA receptors significantly reduced I-burst amplitude without affecting central respiratory rate. Third, blockade of GABAA receptors significantly decreased central respiratory rate by increasing Te and significantly reduced I-burst amplitude. Fourth, blockade of glycine receptors significantly decreased central respiratory rate by causing proportional increases in Ti and Te and significantly reduced I-burst amplitude. These changes in PNA were markedly different from those produced by blockade of EAA or IAA receptors in the pre-B?tzinger complex. We propose that a proper balance of excitatory and inhibitory inputs to several functionally distinct pools of LTF neurons is essential for maintaining the normal pattern of PNA in anesthetized cats.  相似文献   
95.
96.
Background and aim It has been reported that intestinal ischemia–reperfusion (I/R) injury results from oxidative stress caused by increased reactive oxygen species. Dexpanthenol (Dxp) is an alcohol analogue with epitelization, anti-inflammatory, antioxidant, and increasing peristalsis activities. In the present study, the aim was to investigate protective and therapeutic effects of Dxp against intestinal I/R injury. Materials and methods Overall, 40 rats were assigned into five groups including one control, one alone Dxp, and three I/R groups (40-min ischemia; followed by 2-h reperfusion). In two I/R groups, Dxp (500?mg/kg, i.m.) was given before or during ischemia. The histopathological findings including apoptotic changes, and also tissue and serum biochemical parameters levels, were determined. Oxidative stress and ileum damage were assessed by biochemical and histological examination. In the control (n?=?8) and alone Dxp (n?=?8; 500?mg/kg, i.m. of Dxp was given at least 30?min before recording), groups were incised via laparotomy, and electrical activity was recorded from their intestines. In this experiment, the effect of Dxp on the motility of the intestine was examined by analyzing electrical activity. Results In ileum, oxidant levels were found to be higher, while antioxidant levels were found to be lower in I/R groups when compared with controls. Dxp approximated high levels of oxidants than those in the control group, while it increased antioxidant values compared with I/R groups. Histopathological changes caused by intestinal I/R injury and histological improvements were observed in both groups given Dxp. In the Dxp group, electrical signal activity markedly increased compared with the control group. Conclusions Here, it was seen that Dxp had protective and therapeutic effects on intestinal I/R injury and gastrointestinal system peristaltism.  相似文献   
97.
The ongoing COVID-19 pandemic is being responded with various methods, applying vaccines, experimental treatment options, total lockdowns or partial curfews. Weekend curfews are among the methods for reducing the number of infected persons, and this method is practically applied in some countries such as Turkey. In this study, the effect of weekend curfews on reducing the spread of a contagious disease, such as COVID-19, is modeled using a Monte Carlo algorithm with a hybrid lattice model. In the simulation setup, a fictional country with three towns and 26,610 citizens were used as a model. Results indicate that applying a weekend curfew reduces the ratio of ill cases from 0.23 to 0.15. The results also show that applying personal precautions such as social distancing is important for reducing the number of cases and deaths. If the probability of disease spread can be reduced to 0.1, in that case, the death ratio can be minimized down to 0.  相似文献   
98.
The voltage-gated sodium channel NaV1.7 has received much attention from the scientific community due to compelling human genetic data linking gain- and loss-of-function mutations to pain phenotypes. Despite this genetic validation of NaV1.7 as a target for pain, high quality pharmacological tools facilitate further understanding of target biology, establishment of target coverage requirements and subsequent progression into the clinic. Within the sulfonamide class of inhibitors, reduced potency on rat NaV1.7 versus human NaV1.7 was observed, rendering in vivo rat pharmacology studies challenging. Herein, we report the discovery and optimization of novel benzoxazine sulfonamide inhibitors of human, rat and mouse NaV1.7 which enabled pharmacological assessment in traditional behavioral rodent models of pain and in turn, established a connection between formalin-induced pain and histamine-induced pruritus in mice. The latter represents a simple and efficient means of measuring target engagement.  相似文献   
99.
Simultaneous electricity generation and selenium removal was evaluated in single-chamber microbial fuel cells (MFCs) with acetate and glucose as carbon sources. Power output was not affected by selenite up to 125 mg l−1 with glucose as substrate. Coulombic efficiencies of MFCs with glucose increased from 25% to 38% at 150 mg Se l−1. About 99% of 50 and 200 mg Se l−1 selenite was removed in 48 and 72 h for MFCs fed with acetate and glucose, respectively, demonstrating the potential of using MFC technology for Se remediation.  相似文献   
100.
Objective:  To establish whether the presence of signet ring cells (SRCs) in histology sections of breast carcinoma cases was reflected by their presence in fine needle aspiration cytology (FNAC) smears, correlating to the histological type of breast carcinoma.
Methods:  We reviewed the FNAC findings of ten cases that had been diagnosed as primary breast carcinoma with SRCs on histological sections between 1998 and 2007. Slides and histological sections were obtained from the archives of Ege University Hospital.
Results:  FNA smears were reviewed for the following cytomorphological features: background, cellularity, architecture, nuclear pleomorphism and the presence of SRCs. The background was bloody in eight cases, necrotic in one, and clean in one. There was no mucinous material in any of the cases. Cellularity was prominent in five cases (hypercellular), moderate in three (cellular) and low in two (hypocellular). Loosely cohesive groups of tumour cells of varying size were observed in all cases. A plasmacytoid appearance to some of the tumour cells was seen in all cases and discohesive tumour cells were present in eight. Nuclear pleomorphism was high in six cases and moderate in four. SRCs were observed in seven of the ten cases. Two of these seven cases also had a tubular pattern and one had tumour giant cells.
Conclusions:  FNAC should be evaluated carefully regarding the presence of SRCs when cells with a plasmacytoid appearance are observed in either hyper- or hypocellular smears. The presence of single SRCs in FNACs with hypercellularity, high nuclear grade and tubular formation or tumour giant cells may be a clue in favour of ductal carcinoma. The presence of single SRCs in FNACs with hypocellularity and mild to moderate nuclear grade may be suggestive of lobular carcinoma. However, larger studies would be needed to establish the predictive value of the presence of SRCs on FNAC.  相似文献   
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