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2.
B. S. Sharma Sumit Sinha V. S. Mehta A. Suri Aditya Gupta A. K. Mahapatra 《Child's nervous system》2007,23(3):327-333
Object Intracranial aneurysms are rare in children and have different epidemiological, clinical, and morphological characteristics
and outcome from those in adults.
Materials and methods We analyzed demographic, clinical, radiologic features, treatment, and outcome in 55 patients <18 years of age, treated from
Jan 1995 through December 2005.
Results Intracranial aneurysms in children below 18 years constituted 4% of all intracranial aneurysms. Internal Carotid artery (ICA)
bifurcation was the commonest location. About half of the aneurysms were complex. Three-fourth of the patients required surgical
treatment. Two patients died, constituting 5% mortality. Two patients (5%) had poor outcome, whereas the majority (90%) had
a favorable outcome.
Conclusions Pediatric aneurysms have male predominance, higher incidence of clinical features of mass effect or seizures, high incidence
of large, traumatic/mycotic aneurysms, associated illnesses and ICH/IVH and hydrocephalus, better Hunt and Hess grades at
presentation, ICA bifurcation as the commonest site, and better outcome than their adult counterparts. 相似文献
3.
Brain metastasis is the most common intracranial malignancy in adults. Improvements in modern imaging techniques are detecting previously occult brain metastases, and more effective therapies are extending the survival of patients with invasive cancer who have historically died from extracranial disease before developing brain metastasis. This combination of factors along with increased life expectancy has led to the increased diagnosis of brain metastases. Conventional treatment has been whole brain radiotherapy, which can improve symptoms, but potentially results in neurocognitive deficits. Several strategies to improve the therapeutic ratio are currently under investigation to either enhance the radiation effect, thereby preventing tumor recurrence or progression as well as reducing collateral treatment-related brain injury. In this review article, we discuss new directions in the management of brain metastases, including the role of chemical modifiers, novel systemic agents, and the management and prevention of neurocognitive deficits. 相似文献
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6.
D J Mehta 《The Nursing journal of India》1991,82(5):133-135
7.
Chronic ethanol treatment alters the behavioral effects of Ro 15-4513, a partially negative ligand for benzodiazepine binding sites 总被引:2,自引:0,他引:2
Pentylenetetrazol (PTZ)-induced convulsion were studied in control, chronic ethanol-maintained, and ethanol-withdrawal rats. The convulsive doses of PTZ varied among the different groups of rats. Ethanol-maintained rats required higher doses of PTZ to produce convulsions, compared to control and ethanol-withdrawal rats. The partially negative ligands for benzodiazepine binding sites, Ro 15-4513 (2 mg/kg, i.p.) and FG 7142 (20 mg/kg, i.p.) produced proconvulsant effect in saline (control) and ethanol-withdrawal rats as they potentiated the effect of subconvulsive dose of PTZ. A higher dose of Ro 15-4513 (4 mg/kg, i.p.), but not FG 7142 (up to 80 mg/kg, i.p.), also produced proconvulsant effect in ethanol-maintained rats. Furthermore, Ro 15-4513 (5, 10 mg/kg, i.p.), but not FG 7142 (up to 80 mg/kg, i.p.), produced clonic-tonic seizures of short duration in ethanol-withdrawal rats. These effects of Ro 15-4513 and FG 7142 were reversed by diazepam (2 mg/kg, i.p.), as well as by the GABA-neutral Ro 15-1788 (10 mg/kg, i.p.), thereby, indicating the involvement of central benzodiazepine receptors in the action of Ro 15-4513 and FG 7142. These observations suggest that chronic ethanol treatment selectively alters the receptor sensitivity to Ro 15-4513, an ethanol antagonist and partially negative ligand for BZ sites, and this observation supports the notion that ethanol effects are more susceptible to reversal by the imidazobenzodiazepine as compared to other negative ligand for BZ binding sites. 相似文献
8.
Biopsy excision through a fiberoptic bronchoscope in the palliative management of airway obstruction 总被引:1,自引:0,他引:1
Simple biopsy resection through the rigid bronchoscope has been described in the past. We successfully performed such resection through a flexible bronchoscope in six patients with symptomatic and relatively less vascular lesions without complications. In selected patients simple biopsy resection of endobronchial lesion can be safely performed through flexible bronchoscope. 相似文献
9.
Common pancreaticobiliary channels and their relationship to gallstone size in gallstone pancreatitis. 总被引:2,自引:0,他引:2 下载免费PDF全文
Bile reflux into the pancreatic duct after impaction of a stone in a common pancreaticobiliary channel has been suggested to be the initiating factor in gallstone pancreatitis. Such reflux would require that the impacted stone be smaller than the length of the common channel. The incidence of common channels was studied and gallstone size was compared with common channel length in patients with gallstone pancreatitis and those with cholelithiasis or choledocholithiasis without pancreatitis. Sixty-seven per cent of patients with gallstone pancreatitis had a common channel present on intraoperative cholangiography versus 32% of patients with cholelithiasis or choledocholithiasis without pancreatitis (p less than 0.005). Common channel length was greater than the diameter of the smallest stone in nine of 27 patients with gallstone pancreatitis and in 13 of 109 patients with cholelithiasis or choledocholithiasis without pancreatitis (p less than 0.025). In conclusion, common channels are more frequent in patients with gallstone pancreatitis than in patients with other biliary tract disease. Furthermore, gallstone pancreatitis is associated with stones that are smaller than the common channel, which favors obstruction of both pancreatic and bile ducts while allowing reflux of contents between them. 相似文献
10.
Calis Sema Jeyanthi Ramasubbu Tsai Tsuimin Mehta Rahul C. DeLuca Patrick P. 《Pharmaceutical research》1995,12(7):1072-1076
Purpose. The interaction of salmon calcitonin (sCT) and poly (d,l-lactide-co-glycolide) was detected during preparation and evaluation of microspheres. The purpose of this study was to quantitate the extent and nature of the interaction.
Methods. Blank microspheres were prepared by an aqueous emulsification solvent extraction technique. Adsorption studies were carried out at six concentrations of sCT and three concentrations of microspheres. Adsorption isotherms were constructed using the Langmuir and Freundlich treatments.
Results. Adsorption at 1 mg/ml sCT concentration resulted in almost complete depletion of the peptide from the adsorption medium with the time to reach maximum adsorption decreasing with increasing microsphere concentration. At sCT concentrations below 100 µg/ml, a true equilibrium occurred in 1 hour or less while at higher concentrations (up to 350 µg/ml), a transient equilibrium was reached in 1 to 2 hours, followed by further adsorption of the peptide. The adsorption followed the Langmuir isotherm at concentrations below 200 µg/ml, indicating formation of a monolayer. Multilayer interaction, described by the Freundlich isotherm, occurred at higher concentrations and resulted in complete depletion of sCT from the adsorption medium. The affinity constant during monolayer formation was 0.09 and the plateau surface concentration was 5.1 µg/mg. The multilayer peptide-peptide adsorption showed a lower affinity (0.025) but higher capacity (24 µg/mg) than the monolayer peptide-polymer adsorption.
Conclusions. The results show that poly (d,l-lactide-co-glycolide) microspheres have a high adsorption capacity for sCT which must be considered in formulating a controlled delivery product of this peptide. 相似文献