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991.
The present study investigates the effects of resveratrol (RSV) on brain and liver tissues in rats with pembrolizumab (PEMB)-induced toxicity. Obtained for the study were 28 male Sprague-Dawley rats (3–4 months old) which were divided into four groups: Group 1: Control. Group 2: Administered PEMB at 5 mg/kg/day i.p. for a week. Group 3: Administered RSV orally at the dose of 20 mg/kg/day for 30 days by gavage. Group 4: Administered PEMB and RSV at 20 and 5 mg/kg/day RSV, respectively, for 30 days. The results of this study revealed that PEMB leads to a significant increase in thiobarbituric acid reactive substance (TBARS) levels and a significant decrease in glutathione peroxidase (GPx), catalase (CAT), superoxide dismutase (SOD) activities, and glutathione (GSH) levels in the liver and brain tissues. The decreased SOD, CAT, GPx activities, and GSH levels increased significantly following RSV treatment in Group 4. The PEMB treatment showed histopathological alterations associated with strong positive cysteinyl aspartic acid-protease-3 (caspase-3) immunoreactivity, while RSV treatment reduced both the expression of caspase-3 protein and the histopathological changes. RSV administration prevents the biochemical, immunological, and histological alterations induced by PEMB. It can be suggested that the lower caspase-3 immunoreactivity in the PEMB + RSV group than in the PEMB group led to an inhibition of RSV on apoptosis.  相似文献   
992.
OBJECTIVE--To investigate the effect of intravenous magnesium on mortality in suspected acute myocardial infarction. DESIGN--Systematic overview of all available randomised trials in which patients were allocated to receive either intravenous magnesium or otherwise similar treatment without magnesium. SETTING--Coronary care units of several hospitals. PATIENTS--1301 patients in seven randomised trials. MAIN OUTCOME MEASURE--Short term mortality. RESULTS--Considering the seven trials collectively there were 25 (3.8%) deaths among 657 patients allocated to receive magnesium and 53 (8.2%) deaths among 644 patients allocated control, generally during hospital follow up. This represents a 55% reduction in the odds of death (p less than 0.001) with 95% confidence intervals ranging from about one third to about two thirds. 70 of 648 patients allocated magnesium compared with 109 of 641 controls had serious ventricular arrhythmias, suggesting that magnesium reduces the incidence, though the definition varied among trials. Other adverse effects were rare in the limited number of patients for whom this data were available. CONCLUSION--Despite the limited number of patients randomised this overview suggests that intravenous magnesium therapy may reduce mortality in patients with acute myocardial infarction. Further large scale trials to confirm (or refute) these findings are desirable.  相似文献   
993.
In this study, the simultaneously recorded and selectively averaged evoked potentials in some of the structures of the auditory pathway (acoustical cortex, medial geniculate nucleus, inferior colliculus), in the reticular formation and the hippocampus of the cat during sleep as well as the simultaneous amplitude frequency characteristics of these structures are given. The power spectral density functions computed from the simultaneously recorded spontaneous activities of these structures are also presented. Using these results, the following analyses are accomplished:(1) determination of the dynamics of potentials simultaneously obtained from various structures, in order to evaluate the common features of their system characteristics; (2) determination of the relationship (or interactions) between rhythmic activity and evoked potentials of the brain.  相似文献   
994.
A new set of abridged life tables for Pakistan is presented. Data from the 1971 Population Growth Survey were 1st analyzed to estimate the degree of completeness of the reporting of male and female deaths; female deaths were substantially more underreported than male deaths. Age-sex specific mortality schedules were adjusted accordingly. Life expectancy was around 50 years at birth, but increased by 8-9 years for those surviving the substantial risks of dying in the 1st year of life. No significant sex differential in mortality could be discerned from the life tables. The present life tables exhibit mortality levels which are very similar to those observed in the life tables based on the 1962-64 Population Growth Estimation data. The only exception in the present life tables is the lack of a significant improvement in female mortality beyond the reproductive ages possibly because the extent of underreporting of femal deaths found in the 1971 Population Growth Survey was substantially higher than that for males.  相似文献   
995.
Over the past 20 years at least 11 randomised trials of the prevention with diuretics of pre-eclampsia and its sequelae have been undertaken. Nine of these were reviewed. Reliable data from the remaining two were not available. The nine reviewed had investigated a total of nearly 7000 people. Significant evidence of prevention of "pre-eclampsia" was overwhelming, even when oedema was not included as a diagnostic criterion. But as the definitions of pre-eclampsia that had been used depended heavily on increases in blood pressure this evidence may simply have reflected the well known ability of diuretics to reduce blood pressure. When the data on perinatal death were reviewed a little difference was seen in postnatal survival. The incidence of stillbirths was reduced by about one third with treatment, but, perhaps owing to small numbers (only 37 stillbirths), the difference was not significant. Thus these randomised trials failed to provide reliable evidence of either the presence or the absence of any worthwhile effects of treatment with diuretics on perinatal mortality. The implications of this for current and future trials of beta blockers and other agents in the prevention of pre-eclampsia and its sequelae are that extremely large, ultra simple randomised trials are needed, of a size sufficient to permit direct assessment of the effects of treatment not on pre-eclampsia but on perinatal mortality itself. This may require the study of tens of thousands of pregnancies.  相似文献   
996.
In this study, our previous results on the important relation between EEG and EPs were extended by experiments with chronically implanted and freely moving cats, which had electrodes at the acoustical cortex, inferior colliculus and reticular formation. During the experiments the frequency stabilization upon sound stimulation was shown in the frequency domain by comparison of the pre-stimulus power spectra and post-stimulus amplitude frequency characteristics. Comparative frequency domain analysis of about 75 EEG-EPograms (sample of spontaneous activities just prior to stimulation and single evoked potentials following the stimulation), which were recorded from all the brain nuclei mentioned above and from each of the 11 cats, was performed as follows: 1) Power spectra of the EEG-records prior to stimulus were evaluated. 2) Instantaneous frequency characteristics of single EPs were obtained by the Fourier transform. 3) Distribution of the amplitude maxima of the EP-frequency characteristics and the distribution of the EEG-spectral peaks were compared by plotting two types of histograms containing relevant spectral peaks before and after the stimulation. In a frequency range between 1–1000 Hz, the frequency distribution of the EP records from RF and IC were accumulated in narrow discrete frequency channels, whereas, the distribution of the spectral peaks of the EEG depicted frequency spread in broad channels. The frequency stabilization of the EP records from GEA, in the alpha frequency range, was also observed. This effect was described by a factor which we called as the Frequency Stabilization Factor. The results presented in this study showed that the frequency stabilization of the brain's electrical activity induced by sensory stimulation displayed a fluctuation leading to frequency stabilization factors between 0.95 and 5.00. The frequency stabilization and relevant power enhancement upon stimulation strongly support our contention that evoked potential results from the frequency stabilization of the spontaneous activity, triggered by stimulation.Supported by Grant No. TAG-345 of the Scientific and Technical Research Council of Turkey  相似文献   
997.
998.
Irisin is a product of fibronectin type III domain-containing protein 5 (FNDC5) and plays an important role in energy homeostasis. In this study, we aimed to determine effects of intracerebroventricular administration of irisin on the hypothalamus–pituitary–gonadal axis by molecular, biochemical, and morphological findings. Fourty male Wistar-Albino rats were used and divided into four groups including control, sham (vehicle), 10, and 100 nM irisin infused groups (n = 10). Hypothalamic gonadotropin releasing hormone (GnRH) level and serum luteinizing hormone (LH), follicle-stimulating hormone (FSH), and testosterone levels were determined. Testicular tissue histology and spermiogram analysis were also performed. Both irisin concentrations significantly reduced hypothalamic GnRH messenger RNA (mRNA) and protein levels (p < 0.05). It was found that serum LH, FSH, and testosterone levels and Sertoli and Leydig cell numbers were decreased by irisin administration (p < 0.05). In addition, irisin administration reduced sperm density and mobility (p < 0.05). However, it did not cause any change in testicular and epididymis weights and tubular diameter. Our results reveal that irisin can play a role in the central regulation of reproductive behavior and also reduces testosterone levels by suppressing LH and FSH secretion. These results suggest that the discovery of irisin receptor antagonists may be beneficial in the treatment of infertility.  相似文献   
999.

Zinc (Zn) plays crucial roles in mammalian metabolism. There is increasing interest about the potential beneficial effects of Zn on the prevention or treatment of non-communicable diseases. This review critically analyzes the information related to the role of Zn on the metabolic syndrome (MetS) as well as type 2 diabetes (T2D), and summarizes the biological basis of these potential effects of Zn. There are several mechanisms by which Zn may help to prevent the development or progression of MetS and T2D, respectively. Zn is involved in both insulin secretion and action in peripheral tissues. Specifically, Zn has insulin-mimetic properties that increase the activity of the insulin signaling pathway. Zn modulates long-chain polyunsaturated fatty acids levels through its action on the absorption of essential fatty acids in the intestine and its subsequent desaturation. Zn is also involved in both the assembly of chylomicrons and lipoproteins as well as their clearance, and thus, plays a role in lipolysis regulation. Finally, Zn has been found to play a role in redox metabolism, and in turn, on blood pressure. The evidence related to the association between Zn status and occurrence of MetS is inconsistent. Although there are several studies reporting an inverse relationship between Zn status or dietary Zn intake and MetS prevalence, others found a direct relationship between Zn status and MetS prevalence. Intervention studies also provide confusing information about this issue, making it hard to reach firm conclusions. Zn as part of the treatment for patients with T2D has been shown to have positive responses in terms of glucose control outcomes, but only among those with Zn deficiency.

  相似文献   
1000.
The biofilm thickness in membrane biofilm reactors (MBfRs) is an important factor affecting system performance because excessive biofilm formation on the membrane surface inhibits gas diffusion to the interior of the biofilm, resulting in a significant reduction in the performance of contaminant removal. This study provides innovative insights into the control of biofilm thickness in O2-based MBfRs by using the quorum quenching (QQ) method. The study was carried out in MBfRs operated at different gas pressures and hydraulic retention times (HRTs) using QQ beads containing Rhodococcus sp. BH4 at different amounts. The highest performance was observed in reactors operated with 0.21 ml QQ bead/cm2 membrane surface area, 12 HRTs and 1.40 atm. Over this period, the performance increase in chemical oxygen demand (COD) removal was 25%, while the biofilm thickness on the membrane surface was determined to be 250 μm. Moreover, acetate and equivalent oxygen flux results reached 6080 and 10 640 mg·m−2·d−1 maximum values, respectively. The extracellular polymeric substances of the biofilm decreased significantly with the increase of gas pressure and QQ beads amount. Polymerase chain reaction denaturing gradient gel electrophoresis results showed that the microbial community in the MBfR system changed depending on operating conditions and bead amount. The results showed that the QQ method was an effective method to control the biofilm thickness in MBfR and provide insights for future research.  相似文献   
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