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101.
102.
Bergman David Modh Ankit Schultz Lonni Snyder James Mikkelsen Tom Shah Mira Ryu Samuel Siddiqui M. Salim Walbert Tobias 《Journal of neuro-oncology》2020,148(2):353-361
Journal of Neuro-Oncology - Outcomes for patients with recurrent high-grade glioma (HGG) progressing on bevacizumab (BEV) are dismal. Fractionated stereotactic radiosurgery (FSRS) has been shown to... 相似文献
103.
Temporary loss of perivascular aquaporin-4 in neocortex after transient middle cerebral artery occlusion in mice 下载免费PDF全文
Frydenlund DS Bhardwaj A Otsuka T Mylonakou MN Yasumura T Davidson KG Zeynalov E Skare O Laake P Haug FM Rash JE Agre P Ottersen OP Amiry-Moghaddam M 《Proceedings of the National Academy of Sciences of the United States of America》2006,103(36):13532-13536
The aquaporin-4 (AQP4) pool in the perivascular astrocyte membranes has been shown to be critically involved in the formation and dissolution of brain edema. Cerebral edema is a major cause of morbidity and mortality in stroke. It is therefore essential to know whether the perivascular pool of AQP4 is up- or down-regulated after an ischemic insult, because such changes would determine the time course of edema formation. Here we demonstrate by quantitative immunogold cytochemistry that the ischemic striatum and neocortex show distinct patterns of AQP4 expression in the reperfusion phase after 90 min of middle cerebral artery occlusion. The striatal core displays a loss of perivascular AQP4 at 24 hr of reperfusion with no sign of subsequent recovery. The most affected part of the cortex also exhibits loss of perivascular AQP4. This loss is of magnitude similar to that of the striatal core, but it shows a partial recovery toward 72 hr of reperfusion. By freeze fracture we show that the loss of perivascular AQP4 is associated with the disappearance of the square lattices of particles that normally are distinct features of the perivascular astrocyte membrane. The cortical border zone differs from the central part of the ischemic lesion by showing no loss of perivascular AQP4 at 24 hr of reperfusion but rather a slight increase. These data indicate that the size of the AQP4 pool that controls the exchange of fluid between brain and blood during edema formation and dissolution is subject to large and region-specific changes in the reperfusion phase. 相似文献
104.
105.
Epidermal growth factor receptor expression in pancreatic carcinoma using tissue microarray technique 总被引:10,自引:0,他引:10
BACKGROUND: The effect of overexpression of epidermal growth factor receptor (EGFR) in pancreatic carcinoma is not clear. Utilizing tissue microarrays, we evaluated EGFR expression in pancreatic cancer to determine the association of EGFR expression with histopathologic characteristics and patient outcome. METHODS: 71 cases of pancreatic adenocarcinoma and 18 cases of chronic pancreatitis were retrieved from archival files. Tissue cores from donor blocks were arrayed to create a tissue microarray. Sections were stained with EGFR and the intensity of membranous staining and percentage of tumor cells showing immunoreactivity were determined. At least 1% membranous staining and 1+ intensity were considered positive. RESULTS: EGFR was present in 49 of 71 (69%) cases of pancreatic adenocarcinoma and 7 of 18 (39%) cases of chronic pancreatitis (p = 0.03). There was no statistically significant correlation between intensity or extent of EGFR expression and tumor grade, size, or lymph node status. While median survival was nearly twice as long when EGFR was expressed (15.2 vs. 8.3 months), this did not reach statistical significance. CONCLUSIONS: EGFR is overexpressed in pancreatic cancers independent of histopathologic characteristics and does not predict survival. Immunohistochemical analysis of EGFR staining may help in identifying candidates for EGFR inhibitor therapy. 相似文献
106.
Harvinder Dod M.D. Ravindra Bhardwaj M.B.B.S. Preeti Singh M.D. † David Massinople M.D. Venu Sajja M.D. H. James Williams M.D. Ryan H. Livengood M.D. Abnash Jain M.D. Conard Failinger M.D. Navin C. Nanda M.D. † 《Echocardiography (Mount Kisco, N.Y.)》2009,26(7):865-867
Real time two-dimensional transthoracic and transesophageal echocardiography demonstrated a mobile echolucent mass attached to the pulmonary valve in a 25-year-old adult, 20 years following balloon pulmonary valvuloplasty. The mass was surgically excised and pathology showed it to be a cyst. 相似文献
107.
OBJECTIVE: To assess the safety and feasibility of performing computed tomography-guided stereotactic brain lesion biopsy as an outpatient day-surgery procedure. METHODS: In late 1996, a prospective trial of outpatient stereotactic biopsies was initiated. The protocol consists of preadmission education of the patient, computed tomography-guided biopsy with local anesthesia (using a Brown-Roberts-Wells or Cosman-Roberts-Wells frame), postoperative observation in the postanesthetic care unit for 2 hours and in the day surgery unit for 2 hours, and then discharge home 4 hours after the procedure. RESULTS: Seventy-six patients constituted the intent-to-treat group, of whom two were not discharged on the same day (97.4% success rate). The two patients underwent inpatient admission because one required intravenous antibiotic treatment of a brain abscess and the other had a hard lesion in the brainstem that precluded biopsy needle penetration; admission for further investigation of the lesion was elected. Two patients experienced complications (2.6%), i.e., one small area of intraventricular hemorrhage that produced only a mild headache and one case of mild worsening of preexisting leg weakness, with negative computed tomographic results. CONCLUSION: Discharging patients home after 4 hours of observation after stereotactic biopsies seems to be a safe, well-tolerated practice. In this series, there was no major morbidity and no patient was disadvantaged by participating in this protocol. This approach would be expected to result in health care resource and cost savings, with a potential increase in patient satisfaction because of shorter hospital stays. 相似文献
108.
Dry and 24 h imbibed rapeseeds and sesame seeds were defatted with hexane and the resulting freeze-dried powder was analysed for the functional properties of the meals. Water absorption capacity (WAC) of imbibed rapeseed meal and fat absorption capacity (FAC) of both the imbeded meals were higher than those for dry meals. Protein solubility of rapeseed meals was improved by imbibition and both the imbibed meals exhibited maximum protein solubility at pH 12. Rapeseed meal possessed better foaming properties and viscosity than sesame seed meal. Imbibition considerably enhanced the foaming properties of rapeseed meal while the emulsification properties and viscosity did not change appreciably. Emulsification properties of sesame meal were higher than rapeseed meal. 相似文献
109.
Harukuni I Bhardwaj A Shaivitz AB DeVries AC London ED Hurn PD Traystman RJ Kirsch JR Faraci FM 《Stroke; a journal of cerebral circulation》2000,31(4):976-982
BACKGROUND AND PURPOSE: We previously showed that the intravenous administration of the potent final sigma(1)-receptor ligand 4-phenyl-1-(4-phenylbutyl)-piperidine (PPBP) provides neuroprotection against transient focal cerebral ischemia and that the protection depends on treatment duration. We tested the hypothesis that PPBP would provide neuroprotection in a model of transient focal ischemia and 7 days of reperfusion in the rat as assessed with neurobehavioral outcome and infarction volume. METHODS: Under the controlled conditions of normoxia, normocarbia, and normothermia, halothane-anesthetized male Wistar rats were subjected to 2 hours of middle cerebral artery occlusion (MCAO) with the intraluminal suture occlusion technique. We used laser Doppler flowmetry to assess MCAO. At 60 minutes after the onset of ischemia, rats were randomly assigned to 1 of 4 treatment groups in a blinded fashion and received a continuous intravenous infusion of control saline or 0.1, 1, or 10 micromol. kg(-1). h(-1) PPBP for 24 hours. Neurobehavioral evaluation was performed at baseline (3 to 4 days before MCAO) and at 3 and 7 days of reperfusion. Infarction volume was assessed with triphenyltetrazolium chloride staining on day 7 of reperfusion in all rats. RESULTS: Triphenyltetrazolium chloride-determined infarction volume of ipsilateral cortex was smaller in rats treated with 10 micromol. kg(-1). h(-1) PPBP (n=15, 68+/-12 mm(3), 18+/-3% of contralateral structure, P<0.05) (mean+/-SEM) compared with corresponding rats treated with saline (n=15, 114+/-11 mm(3), 31+/-3% of contralateral structure). PPBP did not provide significant neuroprotection in the caudoputamen complex. Although MCAO was associated with several alterations in behavior, the treatment with PPBP had no effect on behavioral outcomes. CONCLUSIONS: The data demonstrate that the potent final sigma(1)-receptor ligand PPBP decreases cortical infarction volume without altering neurobehavior after transient focal ischemia and prolonged reperfusion in the rat. 相似文献
110.
The present investigation elucidates the opioidergic modulation of gonadotropin releasing hormone release mechanism by signal transduction cascade in discrete brain regions from estrogen-progesterone primed ovariectomized rats. The effects of mu-opioid agonist morphine and its antagonist naloxone followed by morphine were studied (in two different groups of rats) on protein kinase A, adenosine 3',5' cyclic monophosphate, protein kinase C and calcium/calmodulin protein kinase-II as well as phospholipase C, phospholipase A(2), diacylglycerol and inositol 1,4, 5-triphosphate. Significant decline in phosphoinositide metabolism was observed after morphine treatment as depicted by decrease in phospholipase C and phospholipase A2 activities as well as inositol 1,4,5-triphosphate and diacylglycerol contents from discrete brain regions. Protein kinase A activity showed translocation from membrane bound to cytosolic form along with a decrease in its activator adenosine 3',5'-cyclic monophosphate levels in morphine-treated group. Calcium/calmodulin dependent protein kinase II activity also declined, whereas, protein kinase C activity increased in the cytosolic fraction after 45 min of morphine administration. Naloxone was seen to counteract the changes induced by morphine in most of the brain regions studied.Morphine also suppressed luteinizing hormone levels, whereas, follicle stimulating hormone level did not change. The present investigation provides evidence for opioidergic mediated suppression of gonadotropin release through the downregulation of signal transduction cascade. 相似文献