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1.
Estrogen is known to modulate the neurotransmission in the brain. The main aim of this study was to investigate the effects of estrogen on the rewarding properties of morphine using conditioned place preference (CPP) paradigm in adult female mice. The possible rewarding effect of estrogen was also examined in ovariectomized mice. Following a 6-day conditioning procedure, sham operated animals showed a significant preference towards the side previously paired with a range of morphine doses (2, 5 and 10—but not 20—mg/kg, SC). However, ovariectomized mice showed decreased CPP compared to gonadally intact mice with a right shift in their morphine dose-response curve. These effects were reversed by chronic daily administration of estradiol benzoate (EB; 20 µg/kg, SC). Furthermore, in ovariectomized mice, EB per se was able to induce CPP. In conclusion, our findings indicate that estradiol has a facilitating effect on morphine reward while its deficiency increases the threshold dose of morphine to induce CPP.  相似文献   
2.
Somatic hybrid cell lines with embryogenic capacity were obtained by fusion of protoplasts isolated from an embryogenic cell line of sugarcane with inactivated protoplasts of an S-(2-aminoethyl)-L-cysteine (Aet-Cys)-resistant cell line of pearl millet. Initial selection for putative hybrids was performed by plating protoplast-derived microcolonies onto medium containing 300 μg of Aet-Cys per ml. Calli growing in the presence of Aet-Cys were screened with respect to their electrophoretic pattern of phosphogluconate dehydrogenase (6-phospho-D-gluconate; EC 1.1.1.44), a dimeric enzyme. The somatic hybrid calli showed both parental homodimer bands plus an intermediate heterodimer band. Somatic hybrid lines were characterized further by electrophoretic patterns of shikimate dehydrogenase (shikimate; EC 1.1.1.25) and arylesterase (aryl-ester hydrolase; EC 3.1.1.2). All cell lines expressed the nuclear genomes of both parents. Use of a maize ribosomal DNA probe allowed the identification of diagnostic ribosomal DNA fragments in Xba I digests of total DNA in both parents and the somatic hybrids. The somatic hybrid lines carried both sugarcane and pearl millet ribosomal DNA fragments. The somatic hybrid calli formed somatic embryos. The banding pattern of phosphogluconate dehydrogenase from the somatic embryos was similar to that of the somatic hybrid calli.  相似文献   
3.
Objective: Extremely low frequency (ELF) and radio frequency (RF) magnetic fields (MFs) pervade our environment. Whether or not these magnetic fields are associated with increased risk of serious diseases, e.g., cancers and Alzheimer's disease, is thus important when developing a rational public policy. The Bioinitiative Report was an effort by internationally recognized scientists who have spent significant time investigating the biological consequences of exposures to these magnetic fields to address this question. Our objective was to provide an unbiased review of the current knowledge and to provide our general and specific conclusions. Results: The evidence indicates that long-term significant occupational exposure to ELF MF may certainly increase the risk of both Alzheimer's disease and breast cancer. There is now evidence that two relevant biological processes (increased production of amyloid beta and decreased production of melatonin) are influenced by high long-term ELF MF exposure that may lead to Alzheimer's disease. There is further evidence that one of these biological processes (decreased melatonin production) may also lead to breast cancer. Finally, there is evidence that exposures to RF MF and ELF MF have similar biological consequences. Conclusion: It is important to mitigate ELF and RF MF exposures through equipment design changes and environmental placement of electrical equipment, e.g., AC/DC transformers. Further research related to these proposed and other biological processes is required.  相似文献   
4.
Summary Somatic hybrid cell lines of Pennisetum americanum + Panicum maximum, and of Pennisetum americanum + Saccharum officinarum display unique mitochondrial DNA (mtDNA) restriction patterns suggestive of mitochondrial fusion and recombination. Apparent recombinant fragments of the hybrids were recovered, cloned, and hybridized to parental and somatic hybrid mtDNAs. In each somatic hybrid, novel fragments were found to be present at low copy number in one or both of the parental mtDNAs, and amplified 15–30 times in the hybrids. In pearl millet-sugarcane somatic hybrid cells, the amplification does not appear to involve enhanced recombination. The presumably amplified restriction fragment of the pearl millet-Guinea grass somatic hybrids is a junction fragment of a repeat, present in low copy number in both parents, and in high copy number in the hybrids. Thus protoplast and probable mitochondrial fusion results in a marked shift in the direction of mtDNA recombination events. We conclude that amplification of parental mtDNA fragments is a common event in somatic hybrid cells of these Gramineae.  相似文献   
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6.

Objective

To investigate if a peristaltic external pneumatic compression device attached to the legs, while scanning, can reduce a substantial risk of fainting in standing weight-bearing magnetic resonance imaging (MRI).

Materials and methods

This study comprised all patients with low back pain referred to standing MRI of the lumbar spine, using a 0.25-T open G-Scanner, from June 2011 to April 2012. The standing MRI protocol included a sagittal TSE T2w and an axial GRE T2w sequence giving a total scan time of 17 min. The first patients were scanned standing without a device (control group), and then from January to April 2012 the patients were scanned in the standing position using an external pneumatic compression device, attached to the legs (experimental group).

Results

One hundred and forty-nine patients (mean age 42.5, standard deviation 12.5, and range 20–77 years) were included and scanned standing. No significant difference in age (p?=?0.51) or gender (p?=?0.47) was observed between the control group (n?=?86) and the experimental group (n?=?63). Sixteen patients (19 %) fainted in the control group during the standing MRI scan, compared to one patient (2 %) in the experimental group where the pneumatic compression device was applied. The difference between groups was highly significant (p?=?0.001; Fisher’s exact test), with an OR?=?0.071 (exact 95 % CI: 0.002 to 0.486) for the pneumatic compression device.

Conclusions

A substantial risk of fainting during standing MRI was almost eliminated by using an external peristaltic pneumatic compression device.  相似文献   
7.
Study ObjectiveTo compare efficacy of rollerball endometrial ablation with low-voltage (cut) versus high-voltage (coag) waveforms.DesignPilot comparative clinical study (Canadian Task Force Classification II-1).SettingUniversity-affiliated teaching hospital.PatientsFifty premenopausal women with menorrhagia.InterventionWomen with menorrhagia were allocated randomly to thermal destruction of the endometrium by a 5-mm rollerball with unmodulated cutting current or modulated coagulating current. Complication rate, clinical outcomes, and need for reintervention were evaluated.Measurements and Main ResultsAt 2 years of follow-up, the reintervention rate was 26.3% in the cutting waveform group versus 31.4% in the coagulating waveform group. This difference was not statistically significant. Hysterectomy was performed in 3 (14%) women in the cutting waveform group and 5 (20%) women in the coagulating waveform group. There were no complications in either group.ConclusionBoth cutting and coagulating waveforms are equally effective for hysteroscopic endometrial ablation with the rollerball.  相似文献   
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9.
Sarcoidosis is a multisystem noncaseating granulomatous disease with a propensity for lung, eye, and skin which recently have been proposed that mycobacterium tuberculosis may contribute in its pathogenesis, and rarely involves central nervous system (CNS). Despite CD4+ lymphocytopenia, sarcoidosis by itself does not increase risk of opportunistic infections other than cryptococcosis. Nonetheless, simultaneous association of CNS cryptococcosis and tuberculosis infection remains extremely rare event in immunocompetent states, and has not been reported in sarcoidosis yet. We here presented such a case in a 42 years old man, a known case of sarcoidosis with diagnostic and therapeutic difficulties were encountered in a fourteen-month-long hospitalization period.  相似文献   
10.
Neurological Sciences - To determine the association of anti-seizure medication (ASM) treatment with outcomes in acute ischemic stroke (AIS) patients undergoing continuous electroencephalography...  相似文献   
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