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We investigated the effect of long‐term exposure to modulation magnetic field (MF), insulin, and their combination on blood–brain barrier (BBB) permeability in a diabetic rat model. Fifty‐three rats were randomly assigned to one of six groups: sham, exposed to no MF; MF, exposed to MF; diabetes mellitus (DM), DM induced with streptozotocin (STZ); DM plus MF (DMMF); DM plus insulin therapy (DMI); and DM plus insulin therapy plus MF (DMIMF). All the rats underwent Evans blue (EB) measurement to evaluate the BBB 30 days after the beginning of experiments. The rats in MF, DMMF, and DMIMF groups were exposed to MF (B = 5 mT) for 165 min every day for 30 days. Mean arterial blood pressure (MABP), body mass, and serum glucose level of the study rats were recorded. The extravasation of brain EB of the MF, DM, DMMF, DMI, and DMIMF groups was higher than that of the sham group and the extravasation of right hemisphere of the DMIMF group was highest (P < 0.05). The post‐procedure body mass of the sham and MF groups were significantly higher than those of the DM and DMMF groups (P < 0.05). In the DM, DMMF, DMI, and DMIMF groups, the baseline glucose was significantly lower than the post‐procedure glucose (P < 0.05). DM and MF increase BBB permeability; in combination, they cause more increase in BBB permeability, and insulin decreases their effect on BBB. Improved glucose metabolism may prevent body mass loss and the hypoglycemic effect of MF. DM increases MABP but MF causes no additional effect. Bioelectromagnetics 31:262–269, 2010. © 2009 Wiley‐Liss, Inc.  相似文献   
3.
Reconstruction of orbital floor fracture using solvent-preserved bone graft   总被引:8,自引:0,他引:8  
The orbital floor is one of the most frequently damaged parts of the maxillofacial skeleton during facial trauma. Unfavorable aesthetic and functional outcomes are frequent when it is treated inadequately. The treatment consists of spanning the floor defect with a material that can provide structural support and restore the orbital volume. This material should also be biocompatible with the surrounding tissues and easily reshaped to fit the orbital floor. Although various autografts or synthetic materials have been used, there is still no consensus on the ideal reconstruction method of orbital floor defects. This study evaluated the applicability of solvent-preserved cadaveric cranial bone graft and its preliminary results in the reconstruction of the orbital floor fractures. Twenty-five orbital floor fractures of 21 patients who underwent surgical repair with cadaveric bone graft during a 2-year period were included in this study. Pure blowout fractures were determined in nine patients, whereas 12 patients had other accompanying maxillofacial fractures. Of the 21 patients, 14 had clinically evident diplopia (66.7 percent), 12 of them had enophthalmos (57.1 percent), and two of them had gaze restriction preoperatively. Reconstruction of the floor of the orbit was performed following either the subciliary or the transconjunctival approach. A cranial allograft was placed over the defect after sufficient exposure. The mean follow-up period was 9 months. Postoperative diplopia, enophthalmos, eye motility, cosmetic appearance, and complications were documented. None of the patients had any evidence of diplopia, limited eye movement, inflammatory reactions in soft tissues, infection, or graft extrusion in the postoperative period. Providing sufficient orbital volume, no graft resorption was detected in computed tomography scan controls. None of the implants required removal for any reason. Enophthalmos was seen in one patient, and temporary scleral show lasting up to 3 to 6 weeks was detected in another three patients. Satisfactory cosmetic results were obtained in all patients. This study showed that solvent-preserved bone, which is a nonsynthetic, human-originated, processed bioimplant, can be safely used in orbital floor repair and can be considered as another reliable treatment alternative.  相似文献   
4.
A review of 35 cases of asymmetric crying facies   总被引:2,自引:0,他引:2  
A review of 35 cases of asymmetric crying facies: Congenital asymmetric crying facies (ACF) is caused by congenital hypoplasia or agenesis of the depressor anguli oris muscle (DAOM) on one side of the mouth. It is well known that this anomaly is frequently associated with cardiovascular, head and neck, musculoskeletal, respiratory, gastrointestinal, central nervous system, and genitourinary anomalies. In this article we report 35 ACF patients (28 children and 7 adults) and found additional abnormalities in 16 of them (i.e. 45%). The abnormalities were cerebral and cerebellar atrophy, mega-cisterna magna, mental motor retardation, convulsions, corpus callosum dysgenesis, cranial bone defect, dermoid cyst, spina bifida occulta, hypertelorism, micrognatia, retrognatia, hemangioma on the lower lip, short frenulum, cleft palate, low-set ears, preauricular tag, mild facial hypoplasia, sternal cleft, congenital heart defect, renal hypoplasia, vesicoureteral reflux, hypertrophic osteoarthropathy, congenital joint contractures, congenital hip dislocation, polydactyly, and umbilical and inguinal hernia. Besides these, one infant was born to a diabetic mother, and had atrial septal defect and the four other children had 4p deletion, Klinefelter syndrome, isolated CD4 deficiency and Treacher-Collins like facial appearance, respectively Although many of these abnormalities were reported in association with ACF, cerebellar atrophy, sternal cleft, cranial bone defect, infant of diabetic mother, 4p deletion, Klinefelter syndrome, isolated CD4 deficiency and Treacher-Collins like facial appearance were not previously published.  相似文献   
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6.
Trace elements are essential components of biological structures, but alternatively, they can be toxic at concentrations beyond those necessary for their biological functions. Changes in the concentration of essential trace elements and heavy metals may affect acute hemorrhagic stroke. The aim of this study was to measure serum levels of essential trace elements [iron (Fe), zinc (Zn), manganese (Mn), copper (Cu), and magnesium (Mg)] and heavy metals [cobalt (Co), cadmium (Cd), and lead (Pb)] in patients with acute hemorrhagic stroke. Twenty-six patients with acute hemorrhagic stroke and 29 healthy controls were enrolled. Atomic absorption spectrophotometry (UNICAM-929) was used to measure serum Fe, Cu, Pb, Cd, Zn, Co, Mn and Mg concentrations. Serum Cd, Pb and Fe levels were significantly higher in patients with acute hemorrhagic stroke than controls (p < 0.001), while serum Cu, Zn, Mg and Mn levels were significantly lower (all p < 0.001). However, there was no significant difference between the groups with respect to serum Co levels (p > 0.05). We first demonstrate increased Cd, Pb, and Fe levels; and decreased Cu, Zn, Mg, and Mn levels in patients with acute hemorrhagic stroke. These findings may have diagnostic and prognostic value for acute hemorrhagic stroke. Further studies are required to elucidate the roles of trace elements and heavy metals in patients with acute hemorrhagic stroke.  相似文献   
7.
Crimean-Congo hemorrhagic fever (CCHF) is an increasing health concern in Turkey since 2002. There were also some recent human cases from the South Marmara region of Turkey; thus, a tick survey was performed, and possible vector tick species for the CCHF virus were determined in the region. A total of 740 adult ticks were collected from infested livestock from five locations: Çanakkale-Biga, Bursa-Orhaneli, Bursa-Keles, Bal?kesir and Bilecik. Total of 11 tick species from the genera Hyalomma, Rhipicephalus, Dermacentor, Ixodes and Haemaphysalis were identified. Rhipicephalus ticks were dominant in the region; the most frequently observed tick species was R. turanicus, (53.1 %), and only 15.4 % of the identified ticks were H. marginatum. The occurrence of H. rufipes infestation in the region fort he first time. A total of 73 pools of adult ticks were tested with both an antigen-detecting ELISA and RT real-time PCR (RT rt PCR). The presence of the CCHF virus was demonstrated in 9 (12.3 %) of the tested tick pools. Although seven of the tick pools were positive for the CCHF virus with both of the methods, one pool was positive only with RT rt PCR and the other pool was only positive with the ELISA. Positive results were obtained from ticks collected from cattle, sheep and goats from two locations, Bursa-Orhaneli and Bilecik. The CCHF virus was detected in R. turanicus (n = 3), R. bursa (n = 2), H. marginatum (n = 2) and D. marginatus (n = 2) ticks. The results of this study confirm the presence of the CCHF virus and present preliminary data on the vector tick species in the southern Marmara region of Turkey.  相似文献   
8.
Ay I  Tuncer M 《Life sciences》2006,79(9):877-882
We investigated the nature and signaling pathways of endothelium- and sensory-nerve ending-derived substances involved in acetylcholine-induced vasodilation in rat isolated perfused kidney. Endothelial denudation by Triton X-100 (0.2%, 0.1 ml) or depletion of afferent nerve endings by capsaicin (10(-6) mol/l) attenuated acetylcholine-induced vasodilation. When these two agents were administered together, the response to acetylcholine was completely inhibited. CGRP1 receptor blocker CGRP 8-37 (10(-7) mol/l) and adenosine A(2) receptor antagonist ZM 241 385 (10(-7) mol/l) inhibited acetylcholine-induced dilation. When indomethacin (10(-5) mol/l), a cyclooxygenase inhibitor, l-NOARG (10(-4) mol/l), a nitric oxide (NO) synthase inhibitor, and potassium chloride (30 mmol/l), to test EDHF response, were perfused simultaneously, the inhibition was greater than that was observed with each agent alone. Guanylate cyclase inhibitor ODQ (10(-5) mol/l) or protein kinase A inhibitor KT 5720 (5x10(-7) mol/l) inhibited acetylcholine-induced dilation. Gap junction uncoupler 18alpha-glycyrrhetinic acid (10(-4) mol/l) caused an uncontrollable increase in basal perfusion pressure making it impossible to test against acetylcholine-induced dilation. Our data suggest that NO, prostanoids, EDHF, and CGRP released from vascular endothelium and afferent nerve endings participate in acetylcholine-induced vasodilation and their signal transduction molecules include protein kinase A and guanylate cyclase.  相似文献   
9.

Purpose

This study examines the subjective acceptance during UHF-CMR in a cohort of healthy volunteers who underwent a cardiac MR examination at 7.0T.

Methods

Within a period of two-and-a-half years (January 2012 to June 2014) a total of 165 healthy volunteers (41 female, 124 male) without any known history of cardiac disease underwent UHF-CMR. For the assessment of the subjective acceptance a questionnaire was used to examine the participants experience prior, during and after the UHF-CMR examination. For this purpose, subjects were asked to respond to the questionnaire in an exit interview held immediately after the completion of the UHF-CMR examination under supervision of a study nurse to ensure accurate understanding of the questions. All questions were answered with “yes” or “no” including space for additional comments.

Results

Transient muscular contraction was documented in 12.7% of the questionnaires. Muscular contraction was reported to occur only during periods of scanning with the magnetic field gradients being rapidly switched. Dizziness during the study was reported by 12.7% of the subjects. Taste of metal was reported by 10.1% of the study population. Light flashes were reported by 3.6% of the entire cohort. 13% of the subjects reported side effects/observations which were not explicitly listed in the questionnaire but covered by the question about other side effects. No severe side effects as vomiting or syncope after scanning occurred. No increase in heart rate was observed during the UHF-CMR exam versus the baseline clinical examination.

Conclusions

This study adds to the literature by detailing the subjective acceptance of cardiovascular magnetic resonance imaging examinations at a magnetic field strength of 7.0T. Cardiac MR examinations at 7.0T are well tolerated by healthy subjects. Broader observational and multi-center studies including patient cohorts with cardiac diseases are required to gain further insights into the subjective acceptance of UHF-CMR examinations.  相似文献   
10.
Supplementation of the semen extender with antioxidants did not produce any significant effect on CASA and progressive motilities and sperm motility characteristics, in comparison to the control group (P > 0.05).  相似文献   
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